diff options
Diffstat (limited to 'kernel')
89 files changed, 8422 insertions, 3202 deletions
diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz index 4af15802ccd..526128a2e62 100644 --- a/kernel/Kconfig.hz +++ b/kernel/Kconfig.hz @@ -54,3 +54,5 @@ config HZ default 300 if HZ_300 default 1000 if HZ_1000 +config SCHED_HRTICK + def_bool HIGH_RES_TIMERS && X86 diff --git a/kernel/Kconfig.instrumentation b/kernel/Kconfig.instrumentation deleted file mode 100644 index 468f47ad750..00000000000 --- a/kernel/Kconfig.instrumentation +++ /dev/null @@ -1,49 +0,0 @@ -menuconfig INSTRUMENTATION - bool "Instrumentation Support" - default y - ---help--- - Say Y here to get to see options related to performance measurement, - system-wide debugging, and testing. This option alone does not add any - kernel code. - - If you say N, all options in this submenu will be skipped and - disabled. If you're trying to debug the kernel itself, go see the - Kernel Hacking menu. - -if INSTRUMENTATION - -config PROFILING - bool "Profiling support (EXPERIMENTAL)" - help - Say Y here to enable the extended profiling support mechanisms used - by profilers such as OProfile. - -config OPROFILE - tristate "OProfile system profiling (EXPERIMENTAL)" - depends on PROFILING && !UML - depends on ARCH_SUPPORTS_OPROFILE || ALPHA || ARM || BLACKFIN || IA64 || M32R || PARISC || PPC || S390 || SUPERH || SPARC - help - OProfile is a profiling system capable of profiling the - whole system, include the kernel, kernel modules, libraries, - and applications. - - If unsure, say N. - -config KPROBES - bool "Kprobes" - depends on KALLSYMS && MODULES && !UML - depends on X86_32 || IA64 || PPC || S390 || SPARC64 || X86_64 || AVR32 - help - Kprobes allows you to trap at almost any kernel address and - execute a callback function. register_kprobe() establishes - a probepoint and specifies the callback. Kprobes is useful - for kernel debugging, non-intrusive instrumentation and testing. - If in doubt, say "N". - -config MARKERS - bool "Activate markers" - help - Place an empty function call at each marker site. Can be - dynamically changed for a probe function. - -endif # INSTRUMENTATION diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt index c64ce9c1420..0669b70fa6a 100644 --- a/kernel/Kconfig.preempt +++ b/kernel/Kconfig.preempt @@ -52,14 +52,13 @@ config PREEMPT endchoice -config PREEMPT_BKL - bool "Preempt The Big Kernel Lock" - depends on SMP || PREEMPT +config RCU_TRACE + bool "Enable tracing for RCU - currently stats in debugfs" + select DEBUG_FS default y help - This option reduces the latency of the kernel by making the - big kernel lock preemptible. + This option provides tracing in RCU which presents stats + in debugfs for debugging RCU implementation. - Say Y here if you are building a kernel for a desktop system. + Say Y here if you want to enable RCU tracing Say N if you are unsure. - diff --git a/kernel/Makefile b/kernel/Makefile index dfa96956dae..135a1b94344 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -8,8 +8,8 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \ signal.o sys.o kmod.o workqueue.o pid.o \ rcupdate.o extable.o params.o posix-timers.o \ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \ - hrtimer.o rwsem.o latency.o nsproxy.o srcu.o \ - utsname.o notifier.o + hrtimer.o rwsem.o nsproxy.o srcu.o \ + utsname.o notifier.o ksysfs.o pm_qos_params.o obj-$(CONFIG_SYSCTL) += sysctl_check.o obj-$(CONFIG_STACKTRACE) += stacktrace.o @@ -36,6 +36,7 @@ obj-$(CONFIG_KALLSYMS) += kallsyms.o obj-$(CONFIG_PM) += power/ obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o obj-$(CONFIG_KEXEC) += kexec.o +obj-$(CONFIG_BACKTRACE_SELF_TEST) += backtracetest.o obj-$(CONFIG_COMPAT) += compat.o obj-$(CONFIG_CGROUPS) += cgroup.o obj-$(CONFIG_CGROUP_DEBUG) += cgroup_debug.o @@ -43,20 +44,26 @@ obj-$(CONFIG_CPUSETS) += cpuset.o obj-$(CONFIG_CGROUP_NS) += ns_cgroup.o obj-$(CONFIG_IKCONFIG) += configs.o obj-$(CONFIG_STOP_MACHINE) += stop_machine.o +obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o obj-$(CONFIG_AUDIT) += audit.o auditfilter.o obj-$(CONFIG_AUDITSYSCALL) += auditsc.o obj-$(CONFIG_AUDIT_TREE) += audit_tree.o obj-$(CONFIG_KPROBES) += kprobes.o -obj-$(CONFIG_SYSFS) += ksysfs.o obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ obj-$(CONFIG_SECCOMP) += seccomp.o obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o +obj-$(CONFIG_CLASSIC_RCU) += rcuclassic.o +obj-$(CONFIG_PREEMPT_RCU) += rcupreempt.o +ifeq ($(CONFIG_PREEMPT_RCU),y) +obj-$(CONFIG_RCU_TRACE) += rcupreempt_trace.o +endif obj-$(CONFIG_RELAY) += relay.o obj-$(CONFIG_SYSCTL) += utsname_sysctl.o obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o obj-$(CONFIG_MARKERS) += marker.o +obj-$(CONFIG_LATENCYTOP) += latencytop.o ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y) # According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is diff --git a/kernel/acct.c b/kernel/acct.c index cf19547cc9e..521dfa53cb9 100644 --- a/kernel/acct.c +++ b/kernel/acct.c @@ -482,7 +482,7 @@ static void do_acct_process(struct file *file) #endif #if ACCT_VERSION==3 ac.ac_pid = current->tgid; - ac.ac_ppid = current->parent->tgid; + ac.ac_ppid = current->real_parent->tgid; #endif spin_lock_irq(¤t->sighand->siglock); diff --git a/kernel/audit.c b/kernel/audit.c index f93c2713017..c8555b18021 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -66,10 +66,11 @@ * (Initialization happens after skb_init is called.) */ static int audit_initialized; -/* 0 - no auditing - * 1 - auditing enabled - * 2 - auditing enabled and configuration is locked/unchangeable. */ +#define AUDIT_OFF 0 +#define AUDIT_ON 1 +#define AUDIT_LOCKED 2 int audit_enabled; +int audit_ever_enabled; /* Default state when kernel boots without any parameters. */ static int audit_default; @@ -152,8 +153,10 @@ struct audit_buffer { static void audit_set_pid(struct audit_buffer *ab, pid_t pid) { - struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); - nlh->nlmsg_pid = pid; + if (ab) { + struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); + nlh->nlmsg_pid = pid; + } } void audit_panic(const char *message) @@ -163,7 +166,8 @@ void audit_panic(const char *message) case AUDIT_FAIL_SILENT: break; case AUDIT_FAIL_PRINTK: - printk(KERN_ERR "audit: %s\n", message); + if (printk_ratelimit()) + printk(KERN_ERR "audit: %s\n", message); break; case AUDIT_FAIL_PANIC: panic("audit: %s\n", message); @@ -231,161 +235,107 @@ void audit_log_lost(const char *message) } if (print) { - printk(KERN_WARNING - "audit: audit_lost=%d audit_rate_limit=%d audit_backlog_limit=%d\n", - atomic_read(&audit_lost), - audit_rate_limit, - audit_backlog_limit); + if (printk_ratelimit()) + printk(KERN_WARNING + "audit: audit_lost=%d audit_rate_limit=%d " + "audit_backlog_limit=%d\n", + atomic_read(&audit_lost), + audit_rate_limit, + audit_backlog_limit); audit_panic(message); } } -static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid) +static int audit_log_config_change(char *function_name, int new, int old, + uid_t loginuid, u32 sid, int allow_changes) { - int res, rc = 0, old = audit_rate_limit; - - /* check if we are locked */ - if (audit_enabled == 2) - res = 0; - else - res = 1; + struct audit_buffer *ab; + int rc = 0; + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); + audit_log_format(ab, "%s=%d old=%d by auid=%u", function_name, new, + old, loginuid); if (sid) { char *ctx = NULL; u32 len; - if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) { - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_rate_limit=%d old=%d by auid=%u" - " subj=%s res=%d", - limit, old, loginuid, ctx, res); + + rc = selinux_sid_to_string(sid, &ctx, &len); + if (rc) { + audit_log_format(ab, " sid=%u", sid); + allow_changes = 0; /* Something weird, deny request */ + } else { + audit_log_format(ab, " subj=%s", ctx); kfree(ctx); - } else - res = 0; /* Something weird, deny request */ + } } - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_rate_limit=%d old=%d by auid=%u res=%d", - limit, old, loginuid, res); - - /* If we are allowed, make the change */ - if (res == 1) - audit_rate_limit = limit; - /* Not allowed, update reason */ - else if (rc == 0) - rc = -EPERM; + audit_log_format(ab, " res=%d", allow_changes); + audit_log_end(ab); return rc; } -static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid) +static int audit_do_config_change(char *function_name, int *to_change, + int new, uid_t loginuid, u32 sid) { - int res, rc = 0, old = audit_backlog_limit; + int allow_changes, rc = 0, old = *to_change; /* check if we are locked */ - if (audit_enabled == 2) - res = 0; + if (audit_enabled == AUDIT_LOCKED) + allow_changes = 0; else - res = 1; + allow_changes = 1; - if (sid) { - char *ctx = NULL; - u32 len; - if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) { - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_backlog_limit=%d old=%d by auid=%u" - " subj=%s res=%d", - limit, old, loginuid, ctx, res); - kfree(ctx); - } else - res = 0; /* Something weird, deny request */ + if (audit_enabled != AUDIT_OFF) { + rc = audit_log_config_change(function_name, new, old, + loginuid, sid, allow_changes); + if (rc) + allow_changes = 0; } - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_backlog_limit=%d old=%d by auid=%u res=%d", - limit, old, loginuid, res); /* If we are allowed, make the change */ - if (res == 1) - audit_backlog_limit = limit; + if (allow_changes == 1) + *to_change = new; /* Not allowed, update reason */ else if (rc == 0) rc = -EPERM; return rc; } -static int audit_set_enabled(int state, uid_t loginuid, u32 sid) +static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid) { - int res, rc = 0, old = audit_enabled; + return audit_do_config_change("audit_rate_limit", &audit_rate_limit, + limit, loginuid, sid); +} + +static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid) +{ + return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit, + limit, loginuid, sid); +} - if (state < 0 || state > 2) +static int audit_set_enabled(int state, uid_t loginuid, u32 sid) +{ + int rc; + if (state < AUDIT_OFF || state > AUDIT_LOCKED) return -EINVAL; - /* check if we are locked */ - if (audit_enabled == 2) - res = 0; - else - res = 1; + rc = audit_do_config_change("audit_enabled", &audit_enabled, state, + loginuid, sid); - if (sid) { - char *ctx = NULL; - u32 len; - if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) { - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_enabled=%d old=%d by auid=%u" - " subj=%s res=%d", - state, old, loginuid, ctx, res); - kfree(ctx); - } else - res = 0; /* Something weird, deny request */ - } - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_enabled=%d old=%d by auid=%u res=%d", - state, old, loginuid, res); + if (!rc) + audit_ever_enabled |= !!state; - /* If we are allowed, make the change */ - if (res == 1) - audit_enabled = state; - /* Not allowed, update reason */ - else if (rc == 0) - rc = -EPERM; return rc; } static int audit_set_failure(int state, uid_t loginuid, u32 sid) { - int res, rc = 0, old = audit_failure; - if (state != AUDIT_FAIL_SILENT && state != AUDIT_FAIL_PRINTK && state != AUDIT_FAIL_PANIC) return -EINVAL; - /* check if we are locked */ - if (audit_enabled == 2) - res = 0; - else - res = 1; - - if (sid) { - char *ctx = NULL; - u32 len; - if ((rc = selinux_sid_to_string(sid, &ctx, &len)) == 0) { - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_failure=%d old=%d by auid=%u" - " subj=%s res=%d", - state, old, loginuid, ctx, res); - kfree(ctx); - } else - res = 0; /* Something weird, deny request */ - } - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_failure=%d old=%d by auid=%u res=%d", - state, old, loginuid, res); - - /* If we are allowed, make the change */ - if (res == 1) - audit_failure = state; - /* Not allowed, update reason */ - else if (rc == 0) - rc = -EPERM; - return rc; + return audit_do_config_change("audit_failure", &audit_failure, state, + loginuid, sid); } static int kauditd_thread(void *dummy) @@ -405,7 +355,11 @@ static int kauditd_thread(void *dummy) audit_pid = 0; } } else { - printk(KERN_NOTICE "%s\n", skb->data + NLMSG_SPACE(0)); + if (printk_ratelimit()) + printk(KERN_NOTICE "%s\n", skb->data + + NLMSG_SPACE(0)); + else + audit_log_lost("printk limit exceeded\n"); kfree_skb(skb); } } else { @@ -573,6 +527,33 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) return err; } +static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type, + u32 pid, u32 uid, uid_t auid, u32 sid) +{ + int rc = 0; + char *ctx = NULL; + u32 len; + + if (!audit_enabled) { + *ab = NULL; + return rc; + } + + *ab = audit_log_start(NULL, GFP_KERNEL, msg_type); + audit_log_format(*ab, "user pid=%d uid=%u auid=%u", + pid, uid, auid); + if (sid) { + rc = selinux_sid_to_string(sid, &ctx, &len); + if (rc) + audit_log_format(*ab, " ssid=%u", sid); + else + audit_log_format(*ab, " subj=%s", ctx); + kfree(ctx); + } + + return rc; +} + static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) { u32 uid, pid, seq, sid; @@ -583,7 +564,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) u16 msg_type = nlh->nlmsg_type; uid_t loginuid; /* loginuid of sender */ struct audit_sig_info *sig_data; - char *ctx; + char *ctx = NULL; u32 len; err = audit_netlink_ok(skb, msg_type); @@ -634,23 +615,14 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) if (err < 0) return err; } if (status_get->mask & AUDIT_STATUS_PID) { - int old = audit_pid; - if (sid) { - if ((err = selinux_sid_to_string( - sid, &ctx, &len))) - return err; - else - audit_log(NULL, GFP_KERNEL, - AUDIT_CONFIG_CHANGE, - "audit_pid=%d old=%d by auid=%u subj=%s", - status_get->pid, old, - loginuid, ctx); - kfree(ctx); - } else - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "audit_pid=%d old=%d by auid=%u", - status_get->pid, old, loginuid); - audit_pid = status_get->pid; + int new_pid = status_get->pid; + + if (audit_enabled != AUDIT_OFF) + audit_log_config_change("audit_pid", new_pid, + audit_pid, loginuid, + sid, 1); + + audit_pid = new_pid; } if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) err = audit_set_rate_limit(status_get->rate_limit, @@ -673,64 +645,35 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) if (err) break; } - ab = audit_log_start(NULL, GFP_KERNEL, msg_type); - if (ab) { - audit_log_format(ab, - "user pid=%d uid=%u auid=%u", - pid, uid, loginuid); - if (sid) { - if (selinux_sid_to_string( - sid, &ctx, &len)) { - audit_log_format(ab, - " ssid=%u", sid); - /* Maybe call audit_panic? */ - } else - audit_log_format(ab, - " subj=%s", ctx); - kfree(ctx); - } - if (msg_type != AUDIT_USER_TTY) - audit_log_format(ab, " msg='%.1024s'", - (char *)data); - else { - int size; - - audit_log_format(ab, " msg="); - size = nlmsg_len(nlh); - audit_log_n_untrustedstring(ab, size, - data); - } - audit_set_pid(ab, pid); - audit_log_end(ab); + audit_log_common_recv_msg(&ab, msg_type, pid, uid, + loginuid, sid); + + if (msg_type != AUDIT_USER_TTY) + audit_log_format(ab, " msg='%.1024s'", + (char *)data); + else { + int size; + + audit_log_format(ab, " msg="); + size = nlmsg_len(nlh); + audit_log_n_untrustedstring(ab, size, + data); } + audit_set_pid(ab, pid); + audit_log_end(ab); } break; case AUDIT_ADD: case AUDIT_DEL: if (nlmsg_len(nlh) < sizeof(struct audit_rule)) return -EINVAL; - if (audit_enabled == 2) { - ab = audit_log_start(NULL, GFP_KERNEL, - AUDIT_CONFIG_CHANGE); - if (ab) { - audit_log_format(ab, - "pid=%d uid=%u auid=%u", - pid, uid, loginuid); - if (sid) { - if (selinux_sid_to_string( - sid, &ctx, &len)) { - audit_log_format(ab, - " ssid=%u", sid); - /* Maybe call audit_panic? */ - } else - audit_log_format(ab, - " subj=%s", ctx); - kfree(ctx); - } - audit_log_format(ab, " audit_enabled=%d res=0", - audit_enabled); - audit_log_end(ab); - } + if (audit_enabled == AUDIT_LOCKED) { + audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid, + uid, loginuid, sid); + + audit_log_format(ab, " audit_enabled=%d res=0", + audit_enabled); + audit_log_end(ab); return -EPERM; } /* fallthrough */ @@ -743,28 +686,13 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) case AUDIT_DEL_RULE: if (nlmsg_len(nlh) < sizeof(struct audit_rule_data)) return -EINVAL; - if (audit_enabled == 2) { - ab = audit_log_start(NULL, GFP_KERNEL, - AUDIT_CONFIG_CHANGE); - if (ab) { - audit_log_format(ab, - "pid=%d uid=%u auid=%u", - pid, uid, loginuid); - if (sid) { - if (selinux_sid_to_string( - sid, &ctx, &len)) { - audit_log_format(ab, - " ssid=%u", sid); - /* Maybe call audit_panic? */ - } else - audit_log_format(ab, - " subj=%s", ctx); - kfree(ctx); - } - audit_log_format(ab, " audit_enabled=%d res=0", - audit_enabled); - audit_log_end(ab); - } + if (audit_enabled == AUDIT_LOCKED) { + audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid, + uid, loginuid, sid); + + audit_log_format(ab, " audit_enabled=%d res=0", + audit_enabled); + audit_log_end(ab); return -EPERM; } /* fallthrough */ @@ -775,19 +703,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) break; case AUDIT_TRIM: audit_trim_trees(); - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); - if (!ab) - break; - audit_log_format(ab, "auid=%u", loginuid); - if (sid) { - u32 len; - ctx = NULL; - if (selinux_sid_to_string(sid, &ctx, &len)) - audit_log_format(ab, " ssid=%u", sid); - else - audit_log_format(ab, " subj=%s", ctx); - kfree(ctx); - } + + audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid, + uid, loginuid, sid); + audit_log_format(ab, " op=trim res=1"); audit_log_end(ab); break; @@ -817,22 +736,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) /* OK, here comes... */ err = audit_tag_tree(old, new); - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); - if (!ab) { - kfree(old); - kfree(new); - break; - } - audit_log_format(ab, "auid=%u", loginuid); - if (sid) { - u32 len; - ctx = NULL; - if (selinux_sid_to_string(sid, &ctx, &len)) - audit_log_format(ab, " ssid=%u", sid); - else - audit_log_format(ab, " subj=%s", ctx); - kfree(ctx); - } + audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid, + uid, loginuid, sid); + audit_log_format(ab, " op=make_equiv old="); audit_log_untrustedstring(ab, old); audit_log_format(ab, " new="); @@ -965,6 +871,7 @@ static int __init audit_init(void) skb_queue_head_init(&audit_skb_queue); audit_initialized = 1; audit_enabled = audit_default; + audit_ever_enabled |= !!audit_default; /* Register the callback with selinux. This callback will be invoked * when a new policy is loaded. */ @@ -992,8 +899,10 @@ static int __init audit_enable(char *str) printk(KERN_INFO "audit: %s%s\n", audit_default ? "enabled" : "disabled", audit_initialized ? "" : " (after initialization)"); - if (audit_initialized) + if (audit_initialized) { audit_enabled = audit_default; + audit_ever_enabled |= !!audit_default; + } return 1; } @@ -1130,7 +1039,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, { struct audit_buffer *ab = NULL; struct timespec t; - unsigned int serial; + unsigned int uninitialized_var(serial); int reserve; unsigned long timeout_start = jiffies; @@ -1164,7 +1073,7 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, remove_wait_queue(&audit_backlog_wait, &wait); continue; } - if (audit_rate_check()) + if (audit_rate_check() && printk_ratelimit()) printk(KERN_WARNING "audit: audit_backlog=%d > " "audit_backlog_limit=%d\n", @@ -1200,13 +1109,17 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, static inline int audit_expand(struct audit_buffer *ab, int extra) { struct sk_buff *skb = ab->skb; - int ret = pskb_expand_head(skb, skb_headroom(skb), extra, - ab->gfp_mask); + int oldtail = skb_tailroom(skb); + int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask); + int newtail = skb_tailroom(skb); + if (ret < 0) { audit_log_lost("out of memory in audit_expand"); return 0; } - return skb_tailroom(skb); + + skb->truesize += newtail - oldtail; + return newtail; } /* @@ -1245,6 +1158,7 @@ static void audit_log_vformat(struct audit_buffer *ab, const char *fmt, goto out; len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2); } + va_end(args2); if (len > 0) skb_put(skb, len); out: @@ -1346,6 +1260,21 @@ static void audit_log_n_string(struct audit_buffer *ab, size_t slen, } /** + * audit_string_contains_control - does a string need to be logged in hex + * @string - string to be checked + * @len - max length of the string to check + */ +int audit_string_contains_control(const char *string, size_t len) +{ + const unsigned char *p; + for (p = string; p < (const unsigned char *)string + len && *p; p++) { + if (*p == '"' || *p < 0x21 || *p > 0x7f) + return 1; + } + return 0; +} + +/** * audit_log_n_untrustedstring - log a string that may contain random characters * @ab: audit_buffer * @len: lenth of string (not including trailing null) @@ -1359,19 +1288,13 @@ static void audit_log_n_string(struct audit_buffer *ab, size_t slen, * The caller specifies the number of characters in the string to log, which may * or may not be the entire string. */ -const char *audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len, - const char *string) +void audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len, + const char *string) { - const unsigned char *p; - - for (p = string; p < (const unsigned char *)string + len && *p; p++) { - if (*p == '"' || *p < 0x21 || *p > 0x7f) { - audit_log_hex(ab, string, len); - return string + len + 1; - } - } - audit_log_n_string(ab, len, string); - return p + 1; + if (audit_string_contains_control(string, len)) + audit_log_hex(ab, string, len); + else + audit_log_n_string(ab, len, string); } /** @@ -1382,9 +1305,9 @@ const char *audit_log_n_untrustedstring(struct audit_buffer *ab, size_t len, * Same as audit_log_n_untrustedstring(), except that strlen is used to * determine string length. */ -const char *audit_log_untrustedstring(struct audit_buffer *ab, const char *string) +void audit_log_untrustedstring(struct audit_buffer *ab, const char *string) { - return audit_log_n_untrustedstring(ab, strlen(string), string); + audit_log_n_untrustedstring(ab, strlen(string), string); } /* This is a helper-function to print the escaped d_path */ @@ -1433,8 +1356,11 @@ void audit_log_end(struct audit_buffer *ab) skb_queue_tail(&audit_skb_queue, ab->skb); ab->skb = NULL; wake_up_interruptible(&kauditd_wait); + } else if (printk_ratelimit()) { + struct nlmsghdr *nlh = nlmsg_hdr(ab->skb); + printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, ab->skb->data + NLMSG_SPACE(0)); } else { - printk(KERN_NOTICE "%s\n", ab->skb->data + NLMSG_SPACE(0)); + audit_log_lost("printk limit exceeded\n"); } } audit_buffer_free(ab); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 5d96f2cc7be..6f19fd477aa 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -95,6 +95,8 @@ extern struct inotify_handle *audit_ih; /* Inotify events we care about. */ #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF +extern int audit_enabled; + void audit_free_parent(struct inotify_watch *i_watch) { struct audit_parent *parent; @@ -974,7 +976,6 @@ static void audit_update_watch(struct audit_parent *parent, struct audit_watch *owatch, *nwatch, *nextw; struct audit_krule *r, *nextr; struct audit_entry *oentry, *nentry; - struct audit_buffer *ab; mutex_lock(&audit_filter_mutex); list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { @@ -1014,13 +1015,18 @@ static void audit_update_watch(struct audit_parent *parent, call_rcu(&oentry->rcu, audit_free_rule_rcu); } - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); - audit_log_format(ab, "op=updated rules specifying path="); - audit_log_untrustedstring(ab, owatch->path); - audit_log_format(ab, " with dev=%u ino=%lu\n", dev, ino); - audit_log_format(ab, " list=%d res=1", r->listnr); - audit_log_end(ab); - + if (audit_enabled) { + struct audit_buffer *ab; + ab = audit_log_start(NULL, GFP_KERNEL, + AUDIT_CONFIG_CHANGE); + audit_log_format(ab, + "op=updated rules specifying path="); + audit_log_untrustedstring(ab, owatch->path); + audit_log_format(ab, " with dev=%u ino=%lu\n", + dev, ino); + audit_log_format(ab, " list=%d res=1", r->listnr); + audit_log_end(ab); + } audit_remove_watch(owatch); goto add_watch_to_parent; /* event applies to a single watch */ } @@ -1039,25 +1045,28 @@ static void audit_remove_parent_watches(struct audit_parent *parent) struct audit_watch *w, *nextw; struct audit_krule *r, *nextr; struct audit_entry *e; - struct audit_buffer *ab; mutex_lock(&audit_filter_mutex); parent->flags |= AUDIT_PARENT_INVALID; list_for_each_entry_safe(w, nextw, &parent->watches, wlist) { list_for_each_entry_safe(r, nextr, &w->rules, rlist) { e = container_of(r, struct audit_entry, rule); - - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); - audit_log_format(ab, "op=remove rule path="); - audit_log_untrustedstring(ab, w->path); - if (r->filterkey) { - audit_log_format(ab, " key="); - audit_log_untrustedstring(ab, r->filterkey); - } else - audit_log_format(ab, " key=(null)"); - audit_log_format(ab, " list=%d res=1", r->listnr); - audit_log_end(ab); - + if (audit_enabled) { + struct audit_buffer *ab; + ab = audit_log_start(NULL, GFP_KERNEL, + AUDIT_CONFIG_CHANGE); + audit_log_format(ab, "op=remove rule path="); + audit_log_untrustedstring(ab, w->path); + if (r->filterkey) { + audit_log_format(ab, " key="); + audit_log_untrustedstring(ab, + r->filterkey); + } else + audit_log_format(ab, " key=(null)"); + audit_log_format(ab, " list=%d res=1", + r->listnr); + audit_log_end(ab); + } list_del(&r->rlist); list_del_rcu(&e->list); call_rcu(&e->rcu, audit_free_rule_rcu); @@ -1495,6 +1504,9 @@ static void audit_log_rule_change(uid_t loginuid, u32 sid, char *action, { struct audit_buffer *ab; + if (!audit_enabled) + return; + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); if (!ab) return; diff --git a/kernel/auditsc.c b/kernel/auditsc.c index bce9ecdb771..1c06ecf38d7 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -70,6 +70,7 @@ #include "audit.h" extern struct list_head audit_filter_list[]; +extern int audit_ever_enabled; /* AUDIT_NAMES is the number of slots we reserve in the audit_context * for saving names from getname(). */ @@ -78,6 +79,9 @@ extern struct list_head audit_filter_list[]; /* Indicates that audit should log the full pathname. */ #define AUDIT_NAME_FULL -1 +/* no execve audit message should be longer than this (userspace limits) */ +#define MAX_EXECVE_AUDIT_LEN 7500 + /* number of audit rules */ int audit_n_rules; @@ -176,7 +180,11 @@ struct audit_aux_data_fd_pair { struct audit_aux_data_pids { struct audit_aux_data d; pid_t target_pid[AUDIT_AUX_PIDS]; + uid_t target_auid[AUDIT_AUX_PIDS]; + uid_t target_uid[AUDIT_AUX_PIDS]; + unsigned int target_sessionid[AUDIT_AUX_PIDS]; u32 target_sid[AUDIT_AUX_PIDS]; + char target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN]; int pid_count; }; @@ -192,7 +200,6 @@ struct audit_context { enum audit_state state; unsigned int serial; /* serial number for record */ struct timespec ctime; /* time of syscall entry */ - uid_t loginuid; /* login uid (identity) */ int major; /* syscall number */ unsigned long argv[4]; /* syscall arguments */ int return_valid; /* return code is valid */ @@ -215,7 +222,11 @@ struct audit_context { int arch; pid_t target_pid; + uid_t target_auid; + uid_t target_uid; + unsigned int target_sessionid; u32 target_sid; + char target_comm[TASK_COMM_LEN]; struct audit_tree_refs *trees, *first_trees; int tree_count; @@ -506,7 +517,7 @@ static int audit_filter_rules(struct task_struct *tsk, case AUDIT_LOGINUID: result = 0; if (ctx) - result = audit_comparator(ctx->loginuid, f->op, f->val); + result = audit_comparator(tsk->loginuid, f->op, f->val); break; case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: @@ -702,7 +713,24 @@ static inline struct audit_context *audit_get_context(struct task_struct *tsk, if (likely(!context)) return NULL; context->return_valid = return_valid; - context->return_code = return_code; + + /* + * we need to fix up the return code in the audit logs if the actual + * return codes are later going to be fixed up by the arch specific + * signal handlers + * + * This is actually a test for: + * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) || + * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK) + * + * but is faster than a bunch of || + */ + if (unlikely(return_code <= -ERESTARTSYS) && + (return_code >= -ERESTART_RESTARTBLOCK) && + (return_code != -ENOIOCTLCMD)) + context->return_code = -EINTR; + else + context->return_code = return_code; if (context->in_syscall && !context->dummy && !context->auditable) { enum audit_state state; @@ -783,11 +811,8 @@ static inline void audit_free_aux(struct audit_context *context) static inline void audit_zero_context(struct audit_context *context, enum audit_state state) { - uid_t loginuid = context->loginuid; - memset(context, 0, sizeof(*context)); context->state = state; - context->loginuid = loginuid; } static inline struct audit_context *audit_alloc_context(enum audit_state state) @@ -814,7 +839,7 @@ int audit_alloc(struct task_struct *tsk) struct audit_context *context; enum audit_state state; - if (likely(!audit_enabled)) + if (likely(!audit_ever_enabled)) return 0; /* Return if not auditing. */ state = audit_filter_task(tsk); @@ -826,11 +851,6 @@ int audit_alloc(struct task_struct *tsk) return -ENOMEM; } - /* Preserve login uid */ - context->loginuid = -1; - if (current->audit_context) - context->loginuid = current->audit_context->loginuid; - tsk->audit_context = context; set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT); return 0; @@ -922,7 +942,8 @@ static void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk } static int audit_log_pid_context(struct audit_context *context, pid_t pid, - u32 sid) + uid_t auid, uid_t uid, unsigned int sessionid, + u32 sid, char *comm) { struct audit_buffer *ab; char *s = NULL; @@ -931,68 +952,204 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid, ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID); if (!ab) - return 1; + return rc; + audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid, auid, + uid, sessionid); if (selinux_sid_to_string(sid, &s, &len)) { - audit_log_format(ab, "opid=%d obj=(none)", pid); + audit_log_format(ab, " obj=(none)"); rc = 1; } else - audit_log_format(ab, "opid=%d obj=%s", pid, s); + audit_log_format(ab, " obj=%s", s); + audit_log_format(ab, " ocomm="); + audit_log_untrustedstring(ab, comm); audit_log_end(ab); kfree(s); return rc; } -static void audit_log_execve_info(struct audit_buffer *ab, - struct audit_aux_data_execve *axi) +/* + * to_send and len_sent accounting are very loose estimates. We aren't + * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being + * within about 500 bytes (next page boundry) + * + * why snprintf? an int is up to 12 digits long. if we just assumed when + * logging that a[%d]= was going to be 16 characters long we would be wasting + * space in every audit message. In one 7500 byte message we can log up to + * about 1000 min size arguments. That comes down to about 50% waste of space + * if we didn't do the snprintf to find out how long arg_num_len was. + */ +static int audit_log_single_execve_arg(struct audit_context *context, + struct audit_buffer **ab, + int arg_num, + size_t *len_sent, + const char __user *p, + char *buf) { - int i; - long len, ret; - const char __user *p; - char *buf; + char arg_num_len_buf[12]; + const char __user *tmp_p = p; + /* how many digits are in arg_num? 3 is the length of a=\n */ + size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3; + size_t len, len_left, to_send; + size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN; + unsigned int i, has_cntl = 0, too_long = 0; + int ret; + + /* strnlen_user includes the null we don't want to send */ + len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1; - if (axi->mm != current->mm) - return; /* execve failed, no additional info */ - - p = (const char __user *)axi->mm->arg_start; + /* + * We just created this mm, if we can't find the strings + * we just copied into it something is _very_ wrong. Similar + * for strings that are too long, we should not have created + * any. + */ + if (unlikely((len = -1) || len > MAX_ARG_STRLEN - 1)) { + WARN_ON(1); + send_sig(SIGKILL, current, 0); + } - for (i = 0; i < axi->argc; i++, p += len) { - len = strnlen_user(p, MAX_ARG_STRLEN); + /* walk the whole argument looking for non-ascii chars */ + do { + if (len_left > MAX_EXECVE_AUDIT_LEN) + to_send = MAX_EXECVE_AUDIT_LEN; + else + to_send = len_left; + ret = copy_from_user(buf, tmp_p, to_send); /* - * We just created this mm, if we can't find the strings - * we just copied into it something is _very_ wrong. Similar - * for strings that are too long, we should not have created - * any. + * There is no reason for this copy to be short. We just + * copied them here, and the mm hasn't been exposed to user- + * space yet. */ - if (!len || len > MAX_ARG_STRLEN) { + if (ret) { WARN_ON(1); send_sig(SIGKILL, current, 0); } - - buf = kmalloc(len, GFP_KERNEL); - if (!buf) { - audit_panic("out of memory for argv string\n"); + buf[to_send] = '\0'; + has_cntl = audit_string_contains_control(buf, to_send); + if (has_cntl) { + /* + * hex messages get logged as 2 bytes, so we can only + * send half as much in each message + */ + max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2; break; } + len_left -= to_send; + tmp_p += to_send; + } while (len_left > 0); + + len_left = len; + + if (len > max_execve_audit_len) + too_long = 1; + + /* rewalk the argument actually logging the message */ + for (i = 0; len_left > 0; i++) { + int room_left; + + if (len_left > max_execve_audit_len) + to_send = max_execve_audit_len; + else + to_send = len_left; + + /* do we have space left to send this argument in this ab? */ + room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent; + if (has_cntl) + room_left -= (to_send * 2); + else + room_left -= to_send; + if (room_left < 0) { + *len_sent = 0; + audit_log_end(*ab); + *ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE); + if (!*ab) + return 0; + } - ret = copy_from_user(buf, p, len); /* - * There is no reason for this copy to be short. We just - * copied them here, and the mm hasn't been exposed to user- - * space yet. + * first record needs to say how long the original string was + * so we can be sure nothing was lost. + */ + if ((i == 0) && (too_long)) + audit_log_format(*ab, "a%d_len=%ld ", arg_num, + has_cntl ? 2*len : len); + + /* + * normally arguments are small enough to fit and we already + * filled buf above when we checked for control characters + * so don't bother with another copy_from_user */ + if (len >= max_execve_audit_len) + ret = copy_from_user(buf, p, to_send); + else + ret = 0; if (ret) { WARN_ON(1); send_sig(SIGKILL, current, 0); } + buf[to_send] = '\0'; + + /* actually log it */ + audit_log_format(*ab, "a%d", arg_num); + if (too_long) + audit_log_format(*ab, "[%d]", i); + audit_log_format(*ab, "="); + if (has_cntl) + audit_log_hex(*ab, buf, to_send); + else + audit_log_format(*ab, "\"%s\"", buf); + audit_log_format(*ab, "\n"); + + p += to_send; + len_left -= to_send; + *len_sent += arg_num_len; + if (has_cntl) + *len_sent += to_send * 2; + else + *len_sent += to_send; + } + /* include the null we didn't log */ + return len + 1; +} - audit_log_format(ab, "a%d=", i); - audit_log_untrustedstring(ab, buf); - audit_log_format(ab, "\n"); +static void audit_log_execve_info(struct audit_context *context, + struct audit_buffer **ab, + struct audit_aux_data_execve *axi) +{ + int i; + size_t len, len_sent = 0; + const char __user *p; + char *buf; + + if (axi->mm != current->mm) + return; /* execve failed, no additional info */ + + p = (const char __user *)axi->mm->arg_start; + + audit_log_format(*ab, "argc=%d ", axi->argc); + + /* + * we need some kernel buffer to hold the userspace args. Just + * allocate one big one rather than allocating one of the right size + * for every single argument inside audit_log_single_execve_arg() + * should be <8k allocation so should be pretty safe. + */ + buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL); + if (!buf) { + audit_panic("out of memory for argv string\n"); + return; + } - kfree(buf); + for (i = 0; i < axi->argc; i++) { + len = audit_log_single_execve_arg(context, ab, i, + &len_sent, p, buf); + if (len <= 0) + break; + p += len; } + kfree(buf); } static void audit_log_exit(struct audit_context *context, struct task_struct *tsk) @@ -1039,7 +1196,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" " ppid=%d pid=%d auid=%u uid=%u gid=%u" " euid=%u suid=%u fsuid=%u" - " egid=%u sgid=%u fsgid=%u tty=%s", + " egid=%u sgid=%u fsgid=%u tty=%s ses=%u", context->argv[0], context->argv[1], context->argv[2], @@ -1047,11 +1204,12 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts context->name_count, context->ppid, context->pid, - context->loginuid, + tsk->loginuid, context->uid, context->gid, context->euid, context->suid, context->fsuid, - context->egid, context->sgid, context->fsgid, tty); + context->egid, context->sgid, context->fsgid, tty, + tsk->sessionid); mutex_unlock(&tty_mutex); @@ -1135,7 +1293,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts case AUDIT_EXECVE: { struct audit_aux_data_execve *axi = (void *)aux; - audit_log_execve_info(ab, axi); + audit_log_execve_info(context, &ab, axi); break; } case AUDIT_SOCKETCALL: { @@ -1168,13 +1326,19 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts for (i = 0; i < axs->pid_count; i++) if (audit_log_pid_context(context, axs->target_pid[i], - axs->target_sid[i])) + axs->target_auid[i], + axs->target_uid[i], + axs->target_sessionid[i], + axs->target_sid[i], + axs->target_comm[i])) call_panic = 1; } if (context->target_pid && audit_log_pid_context(context, context->target_pid, - context->target_sid)) + context->target_auid, context->target_uid, + context->target_sessionid, + context->target_sid, context->target_comm)) call_panic = 1; if (context->pwd && context->pwdmnt) { @@ -1242,6 +1406,11 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts audit_log_end(ab); } + + /* Send end of event record to help user space know we are finished */ + ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE); + if (ab) + audit_log_end(ab); if (call_panic) audit_panic("error converting sid to string"); } @@ -1766,6 +1935,9 @@ void auditsc_get_stamp(struct audit_context *ctx, ctx->auditable = 1; } +/* global counter which is incremented every time something logs in */ +static atomic_t session_id = ATOMIC_INIT(0); + /** * audit_set_loginuid - set a task's audit_context loginuid * @task: task whose audit context is being modified @@ -1777,41 +1949,29 @@ void auditsc_get_stamp(struct audit_context *ctx, */ int audit_set_loginuid(struct task_struct *task, uid_t loginuid) { + unsigned int sessionid = atomic_inc_return(&session_id); struct audit_context *context = task->audit_context; - if (context) { - /* Only log if audit is enabled */ - if (context->in_syscall) { - struct audit_buffer *ab; - - ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); - if (ab) { - audit_log_format(ab, "login pid=%d uid=%u " - "old auid=%u new auid=%u", - task->pid, task->uid, - context->loginuid, loginuid); - audit_log_end(ab); - } + if (context && context->in_syscall) { + struct audit_buffer *ab; + + ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN); + if (ab) { + audit_log_format(ab, "login pid=%d uid=%u " + "old auid=%u new auid=%u" + " old ses=%u new ses=%u", + task->pid, task->uid, + task->loginuid, loginuid, + task->sessionid, sessionid); + audit_log_end(ab); } - context->loginuid = loginuid; } + task->sessionid = sessionid; + task->loginuid = loginuid; return 0; } /** - * audit_get_loginuid - get the loginuid for an audit_context - * @ctx: the audit_context - * - * Returns the context's loginuid or -1 if @ctx is NULL. - */ -uid_t audit_get_loginuid(struct audit_context *ctx) -{ - return ctx ? ctx->loginuid : -1; -} - -EXPORT_SYMBOL(audit_get_loginuid); - -/** * __audit_mq_open - record audit data for a POSIX MQ open * @oflag: open flag * @mode: mode bits @@ -2070,8 +2230,6 @@ int __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode return 0; } -int audit_argv_kb = 32; - int audit_bprm(struct linux_binprm *bprm) { struct audit_aux_data_execve *ax; @@ -2080,14 +2238,6 @@ int audit_bprm(struct linux_binprm *bprm) if (likely(!audit_enabled || !context || context->dummy)) return 0; - /* - * Even though the stack code doesn't limit the arg+env size any more, - * the audit code requires that _all_ arguments be logged in a single - * netlink skb. Hence cap it :-( - */ - if (bprm->argv_len > (audit_argv_kb << 10)) - return -E2BIG; - ax = kmalloc(sizeof(*ax), GFP_KERNEL); if (!ax) return -ENOMEM; @@ -2193,7 +2343,11 @@ void __audit_ptrace(struct task_struct *t) struct audit_context *context = current->audit_context; context->target_pid = t->pid; + context->target_auid = audit_get_loginuid(t); + context->target_uid = t->uid; + context->target_sessionid = audit_get_sessionid(t); selinux_get_task_sid(t, &context->target_sid); + memcpy(context->target_comm, t->comm, TASK_COMM_LEN); } /** @@ -2216,8 +2370,8 @@ int __audit_signal_info(int sig, struct task_struct *t) if (audit_pid && t->tgid == audit_pid) { if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1) { audit_sig_pid = tsk->pid; - if (ctx) - audit_sig_uid = ctx->loginuid; + if (tsk->loginuid != -1) + audit_sig_uid = tsk->loginuid; else audit_sig_uid = tsk->uid; selinux_get_task_sid(tsk, &audit_sig_sid); @@ -2230,7 +2384,11 @@ int __audit_signal_info(int sig, struct task_struct *t) * in audit_context */ if (!ctx->target_pid) { ctx->target_pid = t->tgid; + ctx->target_auid = audit_get_loginuid(t); + ctx->target_uid = t->uid; + ctx->target_sessionid = audit_get_sessionid(t); selinux_get_task_sid(t, &ctx->target_sid); + memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN); return 0; } @@ -2247,7 +2405,11 @@ int __audit_signal_info(int sig, struct task_struct *t) BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS); axp->target_pid[axp->pid_count] = t->tgid; + axp->target_auid[axp->pid_count] = audit_get_loginuid(t); + axp->target_uid[axp->pid_count] = t->uid; + axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t); selinux_get_task_sid(t, &axp->target_sid[axp->pid_count]); + memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN); axp->pid_count++; return 0; @@ -2264,6 +2426,8 @@ void audit_core_dumps(long signr) { struct audit_buffer *ab; u32 sid; + uid_t auid = audit_get_loginuid(current); + unsigned int sessionid = audit_get_sessionid(current); if (!audit_enabled) return; @@ -2272,9 +2436,8 @@ void audit_core_dumps(long signr) return; ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND); - audit_log_format(ab, "auid=%u uid=%u gid=%u", - audit_get_loginuid(current->audit_context), - current->uid, current->gid); + audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u", + auid, current->uid, current->gid, sessionid); selinux_get_task_sid(current, &sid); if (sid) { char *ctx = NULL; diff --git a/kernel/backtracetest.c b/kernel/backtracetest.c new file mode 100644 index 00000000000..d1a7605c5b8 --- /dev/null +++ b/kernel/backtracetest.c @@ -0,0 +1,48 @@ +/* + * Simple stack backtrace regression test module + * + * (C) Copyright 2008 Intel Corporation + * Author: Arjan van de Ven <arjan@linux.intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + */ + +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/delay.h> + +static struct timer_list backtrace_timer; + +static void backtrace_test_timer(unsigned long data) +{ + printk("Testing a backtrace from irq context.\n"); + printk("The following trace is a kernel self test and not a bug!\n"); + dump_stack(); +} +static int backtrace_regression_test(void) +{ + printk("====[ backtrace testing ]===========\n"); + printk("Testing a backtrace from process context.\n"); + printk("The following trace is a kernel self test and not a bug!\n"); + dump_stack(); + + init_timer(&backtrace_timer); + backtrace_timer.function = backtrace_test_timer; + mod_timer(&backtrace_timer, jiffies + 10); + + msleep(10); + printk("====[ end of backtrace testing ]====\n"); + return 0; +} + +static void exitf(void) +{ +} + +module_init(backtrace_regression_test); +module_exit(exitf); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Arjan van de Ven <arjan@linux.intel.com>"); diff --git a/kernel/capability.c b/kernel/capability.c index efbd9cdce13..39e8193b41e 100644 --- a/kernel/capability.c +++ b/kernel/capability.c @@ -22,6 +22,37 @@ static DEFINE_SPINLOCK(task_capability_lock); /* + * Leveraged for setting/resetting capabilities + */ + +const kernel_cap_t __cap_empty_set = CAP_EMPTY_SET; +const kernel_cap_t __cap_full_set = CAP_FULL_SET; +const kernel_cap_t __cap_init_eff_set = CAP_INIT_EFF_SET; + +EXPORT_SYMBOL(__cap_empty_set); +EXPORT_SYMBOL(__cap_full_set); +EXPORT_SYMBOL(__cap_init_eff_set); + +/* + * More recent versions of libcap are available from: + * + * http://www.kernel.org/pub/linux/libs/security/linux-privs/ + */ + +static void warn_legacy_capability_use(void) +{ + static int warned; + if (!warned) { + char name[sizeof(current->comm)]; + + printk(KERN_INFO "warning: `%s' uses 32-bit capabilities" + " (legacy support in use)\n", + get_task_comm(name, current)); + warned = 1; + } +} + +/* * For sys_getproccap() and sys_setproccap(), any of the three * capability set pointers may be NULL -- indicating that that set is * uninteresting and/or not to be changed. @@ -42,12 +73,21 @@ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr) pid_t pid; __u32 version; struct task_struct *target; - struct __user_cap_data_struct data; + unsigned tocopy; + kernel_cap_t pE, pI, pP; if (get_user(version, &header->version)) return -EFAULT; - if (version != _LINUX_CAPABILITY_VERSION) { + switch (version) { + case _LINUX_CAPABILITY_VERSION_1: + warn_legacy_capability_use(); + tocopy = _LINUX_CAPABILITY_U32S_1; + break; + case _LINUX_CAPABILITY_VERSION_2: + tocopy = _LINUX_CAPABILITY_U32S_2; + break; + default: if (put_user(_LINUX_CAPABILITY_VERSION, &header->version)) return -EFAULT; return -EINVAL; @@ -71,14 +111,47 @@ asmlinkage long sys_capget(cap_user_header_t header, cap_user_data_t dataptr) } else target = current; - ret = security_capget(target, &data.effective, &data.inheritable, &data.permitted); + ret = security_capget(target, &pE, &pI, &pP); out: read_unlock(&tasklist_lock); spin_unlock(&task_capability_lock); - if (!ret && copy_to_user(dataptr, &data, sizeof data)) - return -EFAULT; + if (!ret) { + struct __user_cap_data_struct kdata[_LINUX_CAPABILITY_U32S]; + unsigned i; + + for (i = 0; i < tocopy; i++) { + kdata[i].effective = pE.cap[i]; + kdata[i].permitted = pP.cap[i]; + kdata[i].inheritable = pI.cap[i]; + } + + /* + * Note, in the case, tocopy < _LINUX_CAPABILITY_U32S, + * we silently drop the upper capabilities here. This + * has the effect of making older libcap + * implementations implicitly drop upper capability + * bits when they perform a: capget/modify/capset + * sequence. + * + * This behavior is considered fail-safe + * behavior. Upgrading the application to a newer + * version of libcap will enable access to the newer + * capabilities. + * + * An alternative would be to return an error here + * (-ERANGE), but that causes legacy applications to + * unexpectidly fail; the capget/modify/capset aborts + * before modification is attempted and the application + * fails. + */ + + if (copy_to_user(dataptr, kdata, tocopy + * sizeof(struct __user_cap_data_struct))) { + return -EFAULT; + } + } return ret; } @@ -167,6 +240,8 @@ static inline int cap_set_all(kernel_cap_t *effective, */ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) { + struct __user_cap_data_struct kdata[_LINUX_CAPABILITY_U32S]; + unsigned i, tocopy; kernel_cap_t inheritable, permitted, effective; __u32 version; struct task_struct *target; @@ -176,7 +251,15 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) if (get_user(version, &header->version)) return -EFAULT; - if (version != _LINUX_CAPABILITY_VERSION) { + switch (version) { + case _LINUX_CAPABILITY_VERSION_1: + warn_legacy_capability_use(); + tocopy = _LINUX_CAPABILITY_U32S_1; + break; + case _LINUX_CAPABILITY_VERSION_2: + tocopy = _LINUX_CAPABILITY_U32S_2; + break; + default: if (put_user(_LINUX_CAPABILITY_VERSION, &header->version)) return -EFAULT; return -EINVAL; @@ -188,10 +271,22 @@ asmlinkage long sys_capset(cap_user_header_t header, const cap_user_data_t data) if (pid && pid != task_pid_vnr(current) && !capable(CAP_SETPCAP)) return -EPERM; - if (copy_from_user(&effective, &data->effective, sizeof(effective)) || - copy_from_user(&inheritable, &data->inheritable, sizeof(inheritable)) || - copy_from_user(&permitted, &data->permitted, sizeof(permitted))) + if (copy_from_user(&kdata, data, tocopy + * sizeof(struct __user_cap_data_struct))) { return -EFAULT; + } + + for (i = 0; i < tocopy; i++) { + effective.cap[i] = kdata[i].effective; + permitted.cap[i] = kdata[i].permitted; + inheritable.cap[i] = kdata[i].inheritable; + } + while (i < _LINUX_CAPABILITY_U32S) { + effective.cap[i] = 0; + permitted.cap[i] = 0; + inheritable.cap[i] = 0; + i++; + } spin_lock(&task_capability_lock); read_lock(&tasklist_lock); diff --git a/kernel/cpu.c b/kernel/cpu.c index 6b3a0c15144..e0d3a4f56ec 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -15,9 +15,8 @@ #include <linux/stop_machine.h> #include <linux/mutex.h> -/* This protects CPUs going up and down... */ +/* Serializes the updates to cpu_online_map, cpu_present_map */ static DEFINE_MUTEX(cpu_add_remove_lock); -static DEFINE_MUTEX(cpu_bitmask_lock); static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain); @@ -26,52 +25,123 @@ static __cpuinitdata RAW_NOTIFIER_HEAD(cpu_chain); */ static int cpu_hotplug_disabled; -#ifdef CONFIG_HOTPLUG_CPU +static struct { + struct task_struct *active_writer; + struct mutex lock; /* Synchronizes accesses to refcount, */ + /* + * Also blocks the new readers during + * an ongoing cpu hotplug operation. + */ + int refcount; + wait_queue_head_t writer_queue; +} cpu_hotplug; -/* Crappy recursive lock-takers in cpufreq! Complain loudly about idiots */ -static struct task_struct *recursive; -static int recursive_depth; +#define writer_exists() (cpu_hotplug.active_writer != NULL) -void lock_cpu_hotplug(void) +void __init cpu_hotplug_init(void) { - struct task_struct *tsk = current; - - if (tsk == recursive) { - static int warnings = 10; - if (warnings) { - printk(KERN_ERR "Lukewarm IQ detected in hotplug locking\n"); - WARN_ON(1); - warnings--; - } - recursive_depth++; + cpu_hotplug.active_writer = NULL; + mutex_init(&cpu_hotplug.lock); + cpu_hotplug.refcount = 0; + init_waitqueue_head(&cpu_hotplug.writer_queue); +} + +#ifdef CONFIG_HOTPLUG_CPU + +void get_online_cpus(void) +{ + might_sleep(); + if (cpu_hotplug.active_writer == current) return; - } - mutex_lock(&cpu_bitmask_lock); - recursive = tsk; + mutex_lock(&cpu_hotplug.lock); + cpu_hotplug.refcount++; + mutex_unlock(&cpu_hotplug.lock); + } -EXPORT_SYMBOL_GPL(lock_cpu_hotplug); +EXPORT_SYMBOL_GPL(get_online_cpus); -void unlock_cpu_hotplug(void) +void put_online_cpus(void) { - WARN_ON(recursive != current); - if (recursive_depth) { - recursive_depth--; + if (cpu_hotplug.active_writer == current) return; - } - recursive = NULL; - mutex_unlock(&cpu_bitmask_lock); + mutex_lock(&cpu_hotplug.lock); + cpu_hotplug.refcount--; + + if (unlikely(writer_exists()) && !cpu_hotplug.refcount) + wake_up(&cpu_hotplug.writer_queue); + + mutex_unlock(&cpu_hotplug.lock); + } -EXPORT_SYMBOL_GPL(unlock_cpu_hotplug); +EXPORT_SYMBOL_GPL(put_online_cpus); #endif /* CONFIG_HOTPLUG_CPU */ +/* + * The following two API's must be used when attempting + * to serialize the updates to cpu_online_map, cpu_present_map. + */ +void cpu_maps_update_begin(void) +{ + mutex_lock(&cpu_add_remove_lock); +} + +void cpu_maps_update_done(void) +{ + mutex_unlock(&cpu_add_remove_lock); +} + +/* + * This ensures that the hotplug operation can begin only when the + * refcount goes to zero. + * + * Note that during a cpu-hotplug operation, the new readers, if any, + * will be blocked by the cpu_hotplug.lock + * + * Since cpu_maps_update_begin is always called after invoking + * cpu_maps_update_begin, we can be sure that only one writer is active. + * + * Note that theoretically, there is a possibility of a livelock: + * - Refcount goes to zero, last reader wakes up the sleeping + * writer. + * - Last reader unlocks the cpu_hotplug.lock. + * - A new reader arrives at this moment, bumps up the refcount. + * - The writer acquires the cpu_hotplug.lock finds the refcount + * non zero and goes to sleep again. + * + * However, this is very difficult to achieve in practice since + * get_online_cpus() not an api which is called all that often. + * + */ +static void cpu_hotplug_begin(void) +{ + DECLARE_WAITQUEUE(wait, current); + + mutex_lock(&cpu_hotplug.lock); + + cpu_hotplug.active_writer = current; + add_wait_queue_exclusive(&cpu_hotplug.writer_queue, &wait); + while (cpu_hotplug.refcount) { + set_current_state(TASK_UNINTERRUPTIBLE); + mutex_unlock(&cpu_hotplug.lock); + schedule(); + mutex_lock(&cpu_hotplug.lock); + } + remove_wait_queue_locked(&cpu_hotplug.writer_queue, &wait); +} + +static void cpu_hotplug_done(void) +{ + cpu_hotplug.active_writer = NULL; + mutex_unlock(&cpu_hotplug.lock); +} /* Need to know about CPUs going up/down? */ int __cpuinit register_cpu_notifier(struct notifier_block *nb) { int ret; - mutex_lock(&cpu_add_remove_lock); + cpu_maps_update_begin(); ret = raw_notifier_chain_register(&cpu_chain, nb); - mutex_unlock(&cpu_add_remove_lock); + cpu_maps_update_done(); return ret; } @@ -81,9 +151,9 @@ EXPORT_SYMBOL(register_cpu_notifier); void unregister_cpu_notifier(struct notifier_block *nb) { - mutex_lock(&cpu_add_remove_lock); + cpu_maps_update_begin(); raw_notifier_chain_unregister(&cpu_chain, nb); - mutex_unlock(&cpu_add_remove_lock); + cpu_maps_update_done(); } EXPORT_SYMBOL(unregister_cpu_notifier); @@ -147,7 +217,7 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen) if (!cpu_online(cpu)) return -EINVAL; - raw_notifier_call_chain(&cpu_chain, CPU_LOCK_ACQUIRE, hcpu); + cpu_hotplug_begin(); err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls); if (err == NOTIFY_BAD) { @@ -166,9 +236,7 @@ static int _cpu_down(unsigned int cpu, int tasks_frozen) cpu_clear(cpu, tmp); set_cpus_allowed(current, tmp); - mutex_lock(&cpu_bitmask_lock); p = __stop_machine_run(take_cpu_down, &tcd_param, cpu); - mutex_unlock(&cpu_bitmask_lock); if (IS_ERR(p) || cpu_online(cpu)) { /* CPU didn't die: tell everyone. Can't complain. */ @@ -202,7 +270,7 @@ out_thread: out_allowed: set_cpus_allowed(current, old_allowed); out_release: - raw_notifier_call_chain(&cpu_chain, CPU_LOCK_RELEASE, hcpu); + cpu_hotplug_done(); return err; } @@ -210,13 +278,13 @@ int cpu_down(unsigned int cpu) { int err = 0; - mutex_lock(&cpu_add_remove_lock); + cpu_maps_update_begin(); if (cpu_hotplug_disabled) err = -EBUSY; else err = _cpu_down(cpu, 0); - mutex_unlock(&cpu_add_remove_lock); + cpu_maps_update_done(); return err; } #endif /*CONFIG_HOTPLUG_CPU*/ @@ -231,7 +299,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) if (cpu_online(cpu) || !cpu_present(cpu)) return -EINVAL; - raw_notifier_call_chain(&cpu_chain, CPU_LOCK_ACQUIRE, hcpu); + cpu_hotplug_begin(); ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls); if (ret == NOTIFY_BAD) { @@ -243,9 +311,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) } /* Arch-specific enabling code. */ - mutex_lock(&cpu_bitmask_lock); ret = __cpu_up(cpu); - mutex_unlock(&cpu_bitmask_lock); if (ret != 0) goto out_notify; BUG_ON(!cpu_online(cpu)); @@ -257,7 +323,7 @@ out_notify: if (ret != 0) __raw_notifier_call_chain(&cpu_chain, CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL); - raw_notifier_call_chain(&cpu_chain, CPU_LOCK_RELEASE, hcpu); + cpu_hotplug_done(); return ret; } @@ -275,13 +341,13 @@ int __cpuinit cpu_up(unsigned int cpu) return -EINVAL; } - mutex_lock(&cpu_add_remove_lock); + cpu_maps_update_begin(); if (cpu_hotplug_disabled) err = -EBUSY; else err = _cpu_up(cpu, 0); - mutex_unlock(&cpu_add_remove_lock); + cpu_maps_update_done(); return err; } @@ -292,7 +358,7 @@ int disable_nonboot_cpus(void) { int cpu, first_cpu, error = 0; - mutex_lock(&cpu_add_remove_lock); + cpu_maps_update_begin(); first_cpu = first_cpu(cpu_online_map); /* We take down all of the non-boot CPUs in one shot to avoid races * with the userspace trying to use the CPU hotplug at the same time @@ -319,7 +385,7 @@ int disable_nonboot_cpus(void) } else { printk(KERN_ERR "Non-boot CPUs are not disabled\n"); } - mutex_unlock(&cpu_add_remove_lock); + cpu_maps_update_done(); return error; } @@ -328,7 +394,7 @@ void enable_nonboot_cpus(void) int cpu, error; /* Allow everyone to use the CPU hotplug again */ - mutex_lock(&cpu_add_remove_lock); + cpu_maps_update_begin(); cpu_hotplug_disabled = 0; if (cpus_empty(frozen_cpus)) goto out; @@ -344,6 +410,6 @@ void enable_nonboot_cpus(void) } cpus_clear(frozen_cpus); out: - mutex_unlock(&cpu_add_remove_lock); + cpu_maps_update_done(); } #endif /* CONFIG_PM_SLEEP_SMP */ diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 50f5dc46368..cfaf6419d81 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -537,10 +537,10 @@ static int cpusets_overlap(struct cpuset *a, struct cpuset *b) * * Call with cgroup_mutex held. May take callback_mutex during * call due to the kfifo_alloc() and kmalloc() calls. May nest - * a call to the lock_cpu_hotplug()/unlock_cpu_hotplug() pair. + * a call to the get_online_cpus()/put_online_cpus() pair. * Must not be called holding callback_mutex, because we must not - * call lock_cpu_hotplug() while holding callback_mutex. Elsewhere - * the kernel nests callback_mutex inside lock_cpu_hotplug() calls. + * call get_online_cpus() while holding callback_mutex. Elsewhere + * the kernel nests callback_mutex inside get_online_cpus() calls. * So the reverse nesting would risk an ABBA deadlock. * * The three key local variables below are: @@ -691,9 +691,9 @@ restart: rebuild: /* Have scheduler rebuild sched domains */ - lock_cpu_hotplug(); + get_online_cpus(); partition_sched_domains(ndoms, doms); - unlock_cpu_hotplug(); + put_online_cpus(); done: if (q && !IS_ERR(q)) @@ -1617,10 +1617,10 @@ static struct cgroup_subsys_state *cpuset_create( * * If the cpuset being removed has its flag 'sched_load_balance' * enabled, then simulate turning sched_load_balance off, which - * will call rebuild_sched_domains(). The lock_cpu_hotplug() + * will call rebuild_sched_domains(). The get_online_cpus() * call in rebuild_sched_domains() must not be made while holding * callback_mutex. Elsewhere the kernel nests callback_mutex inside - * lock_cpu_hotplug() calls. So the reverse nesting would risk an + * get_online_cpus() calls. So the reverse nesting would risk an * ABBA deadlock. */ diff --git a/kernel/exit.c b/kernel/exit.c index 549c0558ba6..eb9934a82fc 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -50,8 +50,6 @@ #include <asm/pgtable.h> #include <asm/mmu_context.h> -extern void sem_exit (void); - static void exit_mm(struct task_struct * tsk); static void __unhash_process(struct task_struct *p) @@ -249,7 +247,7 @@ static int has_stopped_jobs(struct pid *pgrp) struct task_struct *p; do_each_pid_task(pgrp, PIDTYPE_PGID, p) { - if (p->state != TASK_STOPPED) + if (!task_is_stopped(p)) continue; retval = 1; break; @@ -614,7 +612,7 @@ reparent_thread(struct task_struct *p, struct task_struct *father, int traced) p->parent = p->real_parent; add_parent(p); - if (p->state == TASK_TRACED) { + if (task_is_traced(p)) { /* * If it was at a trace stop, turn it into * a normal stop since it's no longer being @@ -1085,11 +1083,12 @@ do_group_exit(int exit_code) struct signal_struct *const sig = current->signal; struct sighand_struct *const sighand = current->sighand; spin_lock_irq(&sighand->siglock); - if (sig->flags & SIGNAL_GROUP_EXIT) + if (signal_group_exit(sig)) /* Another thread got here before we took the lock. */ exit_code = sig->group_exit_code; else { sig->group_exit_code = exit_code; + sig->flags = SIGNAL_GROUP_EXIT; zap_other_threads(current); } spin_unlock_irq(&sighand->siglock); @@ -1563,60 +1562,49 @@ repeat: } allowed = 1; - switch (p->state) { - case TASK_TRACED: - /* - * When we hit the race with PTRACE_ATTACH, - * we will not report this child. But the - * race means it has not yet been moved to - * our ptrace_children list, so we need to - * set the flag here to avoid a spurious ECHILD - * when the race happens with the only child. - */ - flag = 1; - if (!my_ptrace_child(p)) - continue; - /*FALLTHROUGH*/ - case TASK_STOPPED: + if (task_is_stopped_or_traced(p)) { /* * It's stopped now, so it might later * continue, exit, or stop again. + * + * When we hit the race with PTRACE_ATTACH, we + * will not report this child. But the race + * means it has not yet been moved to our + * ptrace_children list, so we need to set the + * flag here to avoid a spurious ECHILD when + * the race happens with the only child. */ flag = 1; - if (!(options & WUNTRACED) && - !my_ptrace_child(p)) - continue; + + if (!my_ptrace_child(p)) { + if (task_is_traced(p)) + continue; + if (!(options & WUNTRACED)) + continue; + } + retval = wait_task_stopped(p, ret == 2, - (options & WNOWAIT), - infop, - stat_addr, ru); + (options & WNOWAIT), infop, + stat_addr, ru); if (retval == -EAGAIN) goto repeat; if (retval != 0) /* He released the lock. */ goto end; - break; - default: - // case EXIT_DEAD: - if (p->exit_state == EXIT_DEAD) + } else if (p->exit_state == EXIT_ZOMBIE) { + /* + * Eligible but we cannot release it yet: + */ + if (ret == 2) + goto check_continued; + if (!likely(options & WEXITED)) continue; - // case EXIT_ZOMBIE: - if (p->exit_state == EXIT_ZOMBIE) { - /* - * Eligible but we cannot release - * it yet: - */ - if (ret == 2) - goto check_continued; - if (!likely(options & WEXITED)) - continue; - retval = wait_task_zombie( - p, (options & WNOWAIT), - infop, stat_addr, ru); - /* He released the lock. */ - if (retval != 0) - goto end; - break; - } + retval = wait_task_zombie(p, + (options & WNOWAIT), infop, + stat_addr, ru); + /* He released the lock. */ + if (retval != 0) + goto end; + } else if (p->exit_state != EXIT_DEAD) { check_continued: /* * It's running now, so it might later @@ -1625,12 +1613,11 @@ check_continued: flag = 1; if (!unlikely(options & WCONTINUED)) continue; - retval = wait_task_continued( - p, (options & WNOWAIT), - infop, stat_addr, ru); + retval = wait_task_continued(p, + (options & WNOWAIT), infop, + stat_addr, ru); if (retval != 0) /* He released the lock. */ goto end; - break; } } if (!flag) { diff --git a/kernel/extable.c b/kernel/extable.c index 7fe26285531..a26cb2e1702 100644 --- a/kernel/extable.c +++ b/kernel/extable.c @@ -46,7 +46,8 @@ int core_kernel_text(unsigned long addr) addr <= (unsigned long)_etext) return 1; - if (addr >= (unsigned long)_sinittext && + if (system_state == SYSTEM_BOOTING && + addr >= (unsigned long)_sinittext && addr <= (unsigned long)_einittext) return 1; return 0; diff --git a/kernel/fork.c b/kernel/fork.c index 8dd8ff28100..3995297567a 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -51,6 +51,7 @@ #include <linux/random.h> #include <linux/tty.h> #include <linux/proc_fs.h> +#include <linux/blkdev.h> #include <asm/pgtable.h> #include <asm/pgalloc.h> @@ -324,7 +325,7 @@ static inline int mm_alloc_pgd(struct mm_struct * mm) static inline void mm_free_pgd(struct mm_struct * mm) { - pgd_free(mm->pgd); + pgd_free(mm, mm->pgd); } #else #define dup_mmap(mm, oldmm) (0) @@ -392,6 +393,7 @@ void fastcall __mmdrop(struct mm_struct *mm) destroy_context(mm); free_mm(mm); } +EXPORT_SYMBOL_GPL(__mmdrop); /* * Decrement the use count and release all resources for an mm. @@ -791,6 +793,31 @@ out: return error; } +static int copy_io(unsigned long clone_flags, struct task_struct *tsk) +{ +#ifdef CONFIG_BLOCK + struct io_context *ioc = current->io_context; + + if (!ioc) + return 0; + /* + * Share io context with parent, if CLONE_IO is set + */ + if (clone_flags & CLONE_IO) { + tsk->io_context = ioc_task_link(ioc); + if (unlikely(!tsk->io_context)) + return -ENOMEM; + } else if (ioprio_valid(ioc->ioprio)) { + tsk->io_context = alloc_io_context(GFP_KERNEL, -1); + if (unlikely(!tsk->io_context)) + return -ENOMEM; + + tsk->io_context->ioprio = ioc->ioprio; + } +#endif + return 0; +} + /* * Helper to unshare the files of the current task. * We don't want to expose copy_files internals to @@ -1045,6 +1072,10 @@ static struct task_struct *copy_process(unsigned long clone_flags, copy_flags(clone_flags, p); INIT_LIST_HEAD(&p->children); INIT_LIST_HEAD(&p->sibling); +#ifdef CONFIG_PREEMPT_RCU + p->rcu_read_lock_nesting = 0; + p->rcu_flipctr_idx = 0; +#endif /* #ifdef CONFIG_PREEMPT_RCU */ p->vfork_done = NULL; spin_lock_init(&p->alloc_lock); @@ -1059,6 +1090,11 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->prev_utime = cputime_zero; p->prev_stime = cputime_zero; +#ifdef CONFIG_DETECT_SOFTLOCKUP + p->last_switch_count = 0; + p->last_switch_timestamp = 0; +#endif + #ifdef CONFIG_TASK_XACCT p->rchar = 0; /* I/O counter: bytes read */ p->wchar = 0; /* I/O counter: bytes written */ @@ -1082,6 +1118,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, #ifdef CONFIG_SECURITY p->security = NULL; #endif + p->cap_bset = current->cap_bset; p->io_context = NULL; p->audit_context = NULL; cgroup_fork(p); @@ -1147,15 +1184,17 @@ static struct task_struct *copy_process(unsigned long clone_flags, goto bad_fork_cleanup_mm; if ((retval = copy_namespaces(clone_flags, p))) goto bad_fork_cleanup_keys; + if ((retval = copy_io(clone_flags, p))) + goto bad_fork_cleanup_namespaces; retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs); if (retval) - goto bad_fork_cleanup_namespaces; + goto bad_fork_cleanup_io; if (pid != &init_struct_pid) { retval = -ENOMEM; pid = alloc_pid(task_active_pid_ns(p)); if (!pid) - goto bad_fork_cleanup_namespaces; + goto bad_fork_cleanup_io; if (clone_flags & CLONE_NEWPID) { retval = pid_ns_prepare_proc(task_active_pid_ns(p)); @@ -1196,6 +1235,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, #ifdef TIF_SYSCALL_EMU clear_tsk_thread_flag(p, TIF_SYSCALL_EMU); #endif + clear_all_latency_tracing(p); /* Our parent execution domain becomes current domain These must match for thread signalling to apply */ @@ -1224,9 +1264,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, /* Need tasklist lock for parent etc handling! */ write_lock_irq(&tasklist_lock); - /* for sys_ioprio_set(IOPRIO_WHO_PGRP) */ - p->ioprio = current->ioprio; - /* * The task hasn't been attached yet, so its cpus_allowed mask will * not be changed, nor will its assigned CPU. @@ -1237,6 +1274,7 @@ static struct task_struct *copy_process(unsigned long clone_flags, * parent's CPU). This avoids alot of nasty races. */ p->cpus_allowed = current->cpus_allowed; + p->rt.nr_cpus_allowed = current->rt.nr_cpus_allowed; if (unlikely(!cpu_isset(task_cpu(p), p->cpus_allowed) || !cpu_online(task_cpu(p)))) set_task_cpu(p, smp_processor_id()); @@ -1317,6 +1355,8 @@ static struct task_struct *copy_process(unsigned long clone_flags, bad_fork_free_pid: if (pid != &init_struct_pid) free_pid(pid); +bad_fork_cleanup_io: + put_io_context(p->io_context); bad_fork_cleanup_namespaces: exit_task_namespaces(p); bad_fork_cleanup_keys: @@ -1359,7 +1399,7 @@ fork_out: return ERR_PTR(retval); } -noinline struct pt_regs * __devinit __attribute__((weak)) idle_regs(struct pt_regs *regs) +noinline struct pt_regs * __cpuinit __attribute__((weak)) idle_regs(struct pt_regs *regs) { memset(regs, 0, sizeof(struct pt_regs)); return regs; @@ -1411,6 +1451,23 @@ long do_fork(unsigned long clone_flags, int trace = 0; long nr; + /* + * We hope to recycle these flags after 2.6.26 + */ + if (unlikely(clone_flags & CLONE_STOPPED)) { + static int __read_mostly count = 100; + + if (count > 0 && printk_ratelimit()) { + char comm[TASK_COMM_LEN]; + + count--; + printk(KERN_INFO "fork(): process `%s' used deprecated " + "clone flags 0x%lx\n", + get_task_comm(comm, current), + clone_flags & CLONE_STOPPED); + } + } + if (unlikely(current->ptrace)) { trace = fork_traceflag (clone_flags); if (trace) @@ -1453,7 +1510,7 @@ long do_fork(unsigned long clone_flags, if (!(clone_flags & CLONE_STOPPED)) wake_up_new_task(p, clone_flags); else - p->state = TASK_STOPPED; + __set_task_state(p, TASK_STOPPED); if (unlikely (trace)) { current->ptrace_message = nr; diff --git a/kernel/futex.c b/kernel/futex.c index 172a1aeeafd..a6baaec44b8 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -109,6 +109,9 @@ struct futex_q { /* Optional priority inheritance state: */ struct futex_pi_state *pi_state; struct task_struct *task; + + /* Bitset for the optional bitmasked wakeup */ + u32 bitset; }; /* @@ -722,7 +725,7 @@ double_lock_hb(struct futex_hash_bucket *hb1, struct futex_hash_bucket *hb2) * to this virtual address: */ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared, - int nr_wake) + int nr_wake, u32 bitset) { struct futex_hash_bucket *hb; struct futex_q *this, *next; @@ -730,6 +733,9 @@ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared, union futex_key key; int ret; + if (!bitset) + return -EINVAL; + futex_lock_mm(fshared); ret = get_futex_key(uaddr, fshared, &key); @@ -746,6 +752,11 @@ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared, ret = -EINVAL; break; } + + /* Check if one of the bits is set in both bitsets */ + if (!(this->bitset & bitset)) + continue; + wake_futex(this); if (++ret >= nr_wake) break; @@ -1097,15 +1108,15 @@ static void unqueue_me_pi(struct futex_q *q) } /* - * Fixup the pi_state owner with current. + * Fixup the pi_state owner with the new owner. * * Must be called with hash bucket lock held and mm->sem held for non * private futexes. */ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, - struct task_struct *curr) + struct task_struct *newowner) { - u32 newtid = task_pid_vnr(curr) | FUTEX_WAITERS; + u32 newtid = task_pid_vnr(newowner) | FUTEX_WAITERS; struct futex_pi_state *pi_state = q->pi_state; u32 uval, curval, newval; int ret; @@ -1119,12 +1130,12 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, } else newtid |= FUTEX_OWNER_DIED; - pi_state->owner = curr; + pi_state->owner = newowner; - spin_lock_irq(&curr->pi_lock); + spin_lock_irq(&newowner->pi_lock); WARN_ON(!list_empty(&pi_state->list)); - list_add(&pi_state->list, &curr->pi_state_list); - spin_unlock_irq(&curr->pi_lock); + list_add(&pi_state->list, &newowner->pi_state_list); + spin_unlock_irq(&newowner->pi_lock); /* * We own it, so we have to replace the pending owner @@ -1156,7 +1167,7 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, static long futex_wait_restart(struct restart_block *restart); static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, - u32 val, ktime_t *abs_time) + u32 val, ktime_t *abs_time, u32 bitset) { struct task_struct *curr = current; DECLARE_WAITQUEUE(wait, curr); @@ -1167,7 +1178,11 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, struct hrtimer_sleeper t; int rem = 0; + if (!bitset) + return -EINVAL; + q.pi_state = NULL; + q.bitset = bitset; retry: futex_lock_mm(fshared); @@ -1252,6 +1267,8 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, t.timer.expires = *abs_time; hrtimer_start(&t.timer, t.timer.expires, HRTIMER_MODE_ABS); + if (!hrtimer_active(&t.timer)) + t.task = NULL; /* * the timer could have already expired, in which @@ -1293,6 +1310,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, restart->futex.uaddr = (u32 *)uaddr; restart->futex.val = val; restart->futex.time = abs_time->tv64; + restart->futex.bitset = bitset; restart->futex.flags = 0; if (fshared) @@ -1319,7 +1337,8 @@ static long futex_wait_restart(struct restart_block *restart) restart->fn = do_no_restart_syscall; if (restart->futex.flags & FLAGS_SHARED) fshared = ¤t->mm->mmap_sem; - return (long)futex_wait(uaddr, fshared, restart->futex.val, &t); + return (long)futex_wait(uaddr, fshared, restart->futex.val, &t, + restart->futex.bitset); } @@ -1508,9 +1527,37 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared, * when we were on the way back before we locked the * hash bucket. */ - if (q.pi_state->owner == curr && - rt_mutex_trylock(&q.pi_state->pi_mutex)) { - ret = 0; + if (q.pi_state->owner == curr) { + /* + * Try to get the rt_mutex now. This might + * fail as some other task acquired the + * rt_mutex after we removed ourself from the + * rt_mutex waiters list. + */ + if (rt_mutex_trylock(&q.pi_state->pi_mutex)) + ret = 0; + else { + /* + * pi_state is incorrect, some other + * task did a lock steal and we + * returned due to timeout or signal + * without taking the rt_mutex. Too + * late. We can access the + * rt_mutex_owner without locking, as + * the other task is now blocked on + * the hash bucket lock. Fix the state + * up. + */ + struct task_struct *owner; + int res; + + owner = rt_mutex_owner(&q.pi_state->pi_mutex); + res = fixup_pi_state_owner(uaddr, &q, owner); + + /* propagate -EFAULT, if the fixup failed */ + if (res) + ret = res; + } } else { /* * Paranoia check. If we did not take the lock @@ -1912,7 +1959,8 @@ retry: * PI futexes happens in exit_pi_state(): */ if (!pi && (uval & FUTEX_WAITERS)) - futex_wake(uaddr, &curr->mm->mmap_sem, 1); + futex_wake(uaddr, &curr->mm->mmap_sem, 1, + FUTEX_BITSET_MATCH_ANY); } return 0; } @@ -2012,10 +2060,14 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, switch (cmd) { case FUTEX_WAIT: - ret = futex_wait(uaddr, fshared, val, timeout); + val3 = FUTEX_BITSET_MATCH_ANY; + case FUTEX_WAIT_BITSET: + ret = futex_wait(uaddr, fshared, val, timeout, val3); break; case FUTEX_WAKE: - ret = futex_wake(uaddr, fshared, val); + val3 = FUTEX_BITSET_MATCH_ANY; + case FUTEX_WAKE_BITSET: + ret = futex_wake(uaddr, fshared, val, val3); break; case FUTEX_FD: /* non-zero val means F_SETOWN(getpid()) & F_SETSIG(val) */ @@ -2055,7 +2107,8 @@ asmlinkage long sys_futex(u32 __user *uaddr, int op, u32 val, u32 val2 = 0; int cmd = op & FUTEX_CMD_MASK; - if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI)) { + if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || + cmd == FUTEX_WAIT_BITSET)) { if (copy_from_user(&ts, utime, sizeof(ts)) != 0) return -EFAULT; if (!timespec_valid(&ts)) diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c index 0a43def6fee..133d558db45 100644 --- a/kernel/futex_compat.c +++ b/kernel/futex_compat.c @@ -167,7 +167,8 @@ asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val, int val2 = 0; int cmd = op & FUTEX_CMD_MASK; - if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI)) { + if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || + cmd == FUTEX_WAIT_BITSET)) { if (get_compat_timespec(&ts, utime)) return -EFAULT; if (!timespec_valid(&ts)) diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index e65dd0b47cd..668f3967eb3 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -306,7 +306,7 @@ EXPORT_SYMBOL_GPL(ktime_sub_ns); /* * Divide a ktime value by a nanosecond value */ -unsigned long ktime_divns(const ktime_t kt, s64 div) +u64 ktime_divns(const ktime_t kt, s64 div) { u64 dclc, inc, dns; int sft = 0; @@ -321,10 +321,26 @@ unsigned long ktime_divns(const ktime_t kt, s64 div) dclc >>= sft; do_div(dclc, (unsigned long) div); - return (unsigned long) dclc; + return dclc; } #endif /* BITS_PER_LONG >= 64 */ +/* + * Check, whether the timer is on the callback pending list + */ +static inline int hrtimer_cb_pending(const struct hrtimer *timer) +{ + return timer->state & HRTIMER_STATE_PENDING; +} + +/* + * Remove a timer from the callback pending list + */ +static inline void hrtimer_remove_cb_pending(struct hrtimer *timer) +{ + list_del_init(&timer->cb_entry); +} + /* High resolution timer related functions */ #ifdef CONFIG_HIGH_RES_TIMERS @@ -494,29 +510,12 @@ void hres_timers_resume(void) } /* - * Check, whether the timer is on the callback pending list - */ -static inline int hrtimer_cb_pending(const struct hrtimer *timer) -{ - return timer->state & HRTIMER_STATE_PENDING; -} - -/* - * Remove a timer from the callback pending list - */ -static inline void hrtimer_remove_cb_pending(struct hrtimer *timer) -{ - list_del_init(&timer->cb_entry); -} - -/* * Initialize the high resolution related parts of cpu_base */ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { base->expires_next.tv64 = KTIME_MAX; base->hres_active = 0; - INIT_LIST_HEAD(&base->cb_pending); } /* @@ -524,7 +523,6 @@ static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) */ static inline void hrtimer_init_timer_hres(struct hrtimer *timer) { - INIT_LIST_HEAD(&timer->cb_entry); } /* @@ -618,10 +616,13 @@ static inline int hrtimer_enqueue_reprogram(struct hrtimer *timer, { return 0; } -static inline int hrtimer_cb_pending(struct hrtimer *timer) { return 0; } -static inline void hrtimer_remove_cb_pending(struct hrtimer *timer) { } static inline void hrtimer_init_hres(struct hrtimer_cpu_base *base) { } static inline void hrtimer_init_timer_hres(struct hrtimer *timer) { } +static inline int hrtimer_reprogram(struct hrtimer *timer, + struct hrtimer_clock_base *base) +{ + return 0; +} #endif /* CONFIG_HIGH_RES_TIMERS */ @@ -655,10 +656,9 @@ void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags) * Forward the timer expiry so it will expire in the future. * Returns the number of overruns. */ -unsigned long -hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval) +u64 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval) { - unsigned long orun = 1; + u64 orun = 1; ktime_t delta; delta = ktime_sub(now, timer->expires); @@ -1001,6 +1001,7 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id, clock_id = CLOCK_MONOTONIC; timer->base = &cpu_base->clock_base[clock_id]; + INIT_LIST_HEAD(&timer->cb_entry); hrtimer_init_timer_hres(timer); #ifdef CONFIG_TIMER_STATS @@ -1030,6 +1031,85 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) } EXPORT_SYMBOL_GPL(hrtimer_get_res); +static void run_hrtimer_pending(struct hrtimer_cpu_base *cpu_base) +{ + spin_lock_irq(&cpu_base->lock); + + while (!list_empty(&cpu_base->cb_pending)) { + enum hrtimer_restart (*fn)(struct hrtimer *); + struct hrtimer *timer; + int restart; + + timer = list_entry(cpu_base->cb_pending.next, + struct hrtimer, cb_entry); + + timer_stats_account_hrtimer(timer); + + fn = timer->function; + __remove_hrtimer(timer, timer->base, HRTIMER_STATE_CALLBACK, 0); + spin_unlock_irq(&cpu_base->lock); + + restart = fn(timer); + + spin_lock_irq(&cpu_base->lock); + + timer->state &= ~HRTIMER_STATE_CALLBACK; + if (restart == HRTIMER_RESTART) { + BUG_ON(hrtimer_active(timer)); + /* + * Enqueue the timer, allow reprogramming of the event + * device + */ + enqueue_hrtimer(timer, timer->base, 1); + } else if (hrtimer_active(timer)) { + /* + * If the timer was rearmed on another CPU, reprogram + * the event device. + */ + if (timer->base->first == &timer->node) + hrtimer_reprogram(timer, timer->base); + } + } + spin_unlock_irq(&cpu_base->lock); +} + +static void __run_hrtimer(struct hrtimer *timer) +{ + struct hrtimer_clock_base *base = timer->base; + struct hrtimer_cpu_base *cpu_base = base->cpu_base; + enum hrtimer_restart (*fn)(struct hrtimer *); + int restart; + + __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0); + timer_stats_account_hrtimer(timer); + + fn = timer->function; + if (timer->cb_mode == HRTIMER_CB_IRQSAFE_NO_SOFTIRQ) { + /* + * Used for scheduler timers, avoid lock inversion with + * rq->lock and tasklist_lock. + * + * These timers are required to deal with enqueue expiry + * themselves and are not allowed to migrate. + */ + spin_unlock(&cpu_base->lock); + restart = fn(timer); + spin_lock(&cpu_base->lock); + } else + restart = fn(timer); + + /* + * Note: We clear the CALLBACK bit after enqueue_hrtimer to avoid + * reprogramming of the event hardware. This happens at the end of this + * function anyway. + */ + if (restart != HRTIMER_NORESTART) { + BUG_ON(timer->state != HRTIMER_STATE_CALLBACK); + enqueue_hrtimer(timer, base, 0); + } + timer->state &= ~HRTIMER_STATE_CALLBACK; +} + #ifdef CONFIG_HIGH_RES_TIMERS /* @@ -1087,21 +1167,7 @@ void hrtimer_interrupt(struct clock_event_device *dev) continue; } - __remove_hrtimer(timer, base, - HRTIMER_STATE_CALLBACK, 0); - timer_stats_account_hrtimer(timer); - - /* - * Note: We clear the CALLBACK bit after - * enqueue_hrtimer to avoid reprogramming of - * the event hardware. This happens at the end - * of this function anyway. - */ - if (timer->function(timer) != HRTIMER_NORESTART) { - BUG_ON(timer->state != HRTIMER_STATE_CALLBACK); - enqueue_hrtimer(timer, base, 0); - } - timer->state &= ~HRTIMER_STATE_CALLBACK; + __run_hrtimer(timer); } spin_unlock(&cpu_base->lock); base++; @@ -1122,52 +1188,41 @@ void hrtimer_interrupt(struct clock_event_device *dev) static void run_hrtimer_softirq(struct softirq_action *h) { - struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases); - - spin_lock_irq(&cpu_base->lock); - - while (!list_empty(&cpu_base->cb_pending)) { - enum hrtimer_restart (*fn)(struct hrtimer *); - struct hrtimer *timer; - int restart; - - timer = list_entry(cpu_base->cb_pending.next, - struct hrtimer, cb_entry); + run_hrtimer_pending(&__get_cpu_var(hrtimer_bases)); +} - timer_stats_account_hrtimer(timer); +#endif /* CONFIG_HIGH_RES_TIMERS */ - fn = timer->function; - __remove_hrtimer(timer, timer->base, HRTIMER_STATE_CALLBACK, 0); - spin_unlock_irq(&cpu_base->lock); +/* + * Called from timer softirq every jiffy, expire hrtimers: + * + * For HRT its the fall back code to run the softirq in the timer + * softirq context in case the hrtimer initialization failed or has + * not been done yet. + */ +void hrtimer_run_pending(void) +{ + struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases); - restart = fn(timer); + if (hrtimer_hres_active()) + return; - spin_lock_irq(&cpu_base->lock); + /* + * This _is_ ugly: We have to check in the softirq context, + * whether we can switch to highres and / or nohz mode. The + * clocksource switch happens in the timer interrupt with + * xtime_lock held. Notification from there only sets the + * check bit in the tick_oneshot code, otherwise we might + * deadlock vs. xtime_lock. + */ + if (tick_check_oneshot_change(!hrtimer_is_hres_enabled())) + hrtimer_switch_to_hres(); - timer->state &= ~HRTIMER_STATE_CALLBACK; - if (restart == HRTIMER_RESTART) { - BUG_ON(hrtimer_active(timer)); - /* - * Enqueue the timer, allow reprogramming of the event - * device - */ - enqueue_hrtimer(timer, timer->base, 1); - } else if (hrtimer_active(timer)) { - /* - * If the timer was rearmed on another CPU, reprogram - * the event device. - */ - if (timer->base->first == &timer->node) - hrtimer_reprogram(timer, timer->base); - } - } - spin_unlock_irq(&cpu_base->lock); + run_hrtimer_pending(cpu_base); } -#endif /* CONFIG_HIGH_RES_TIMERS */ - /* - * Expire the per base hrtimer-queue: + * Called from hardirq context every jiffy */ static inline void run_hrtimer_queue(struct hrtimer_cpu_base *cpu_base, int index) @@ -1181,46 +1236,27 @@ static inline void run_hrtimer_queue(struct hrtimer_cpu_base *cpu_base, if (base->get_softirq_time) base->softirq_time = base->get_softirq_time(); - spin_lock_irq(&cpu_base->lock); + spin_lock(&cpu_base->lock); while ((node = base->first)) { struct hrtimer *timer; - enum hrtimer_restart (*fn)(struct hrtimer *); - int restart; timer = rb_entry(node, struct hrtimer, node); if (base->softirq_time.tv64 <= timer->expires.tv64) break; -#ifdef CONFIG_HIGH_RES_TIMERS - WARN_ON_ONCE(timer->cb_mode == HRTIMER_CB_IRQSAFE_NO_SOFTIRQ); -#endif - timer_stats_account_hrtimer(timer); - - fn = timer->function; - __remove_hrtimer(timer, base, HRTIMER_STATE_CALLBACK, 0); - spin_unlock_irq(&cpu_base->lock); - - restart = fn(timer); - - spin_lock_irq(&cpu_base->lock); - - timer->state &= ~HRTIMER_STATE_CALLBACK; - if (restart != HRTIMER_NORESTART) { - BUG_ON(hrtimer_active(timer)); - enqueue_hrtimer(timer, base, 0); + if (timer->cb_mode == HRTIMER_CB_SOFTIRQ) { + __remove_hrtimer(timer, base, HRTIMER_STATE_PENDING, 0); + list_add_tail(&timer->cb_entry, + &base->cpu_base->cb_pending); + continue; } + + __run_hrtimer(timer); } - spin_unlock_irq(&cpu_base->lock); + spin_unlock(&cpu_base->lock); } -/* - * Called from timer softirq every jiffy, expire hrtimers: - * - * For HRT its the fall back code to run the softirq in the timer - * softirq context in case the hrtimer initialization failed or has - * not been done yet. - */ void hrtimer_run_queues(void) { struct hrtimer_cpu_base *cpu_base = &__get_cpu_var(hrtimer_bases); @@ -1229,18 +1265,6 @@ void hrtimer_run_queues(void) if (hrtimer_hres_active()) return; - /* - * This _is_ ugly: We have to check in the softirq context, - * whether we can switch to highres and / or nohz mode. The - * clocksource switch happens in the timer interrupt with - * xtime_lock held. Notification from there only sets the - * check bit in the tick_oneshot code, otherwise we might - * deadlock vs. xtime_lock. - */ - if (tick_check_oneshot_change(!hrtimer_is_hres_enabled())) - if (hrtimer_switch_to_hres()) - return; - hrtimer_get_softirq_time(cpu_base); for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) @@ -1268,7 +1292,7 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task) sl->timer.function = hrtimer_wakeup; sl->task = task; #ifdef CONFIG_HIGH_RES_TIMERS - sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_RESTART; + sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; #endif } @@ -1279,6 +1303,8 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod do { set_current_state(TASK_INTERRUPTIBLE); hrtimer_start(&t->timer, t->timer.expires, mode); + if (!hrtimer_active(&t->timer)) + t->task = NULL; if (likely(t->task)) schedule(); @@ -1288,6 +1314,8 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod } while (t->task && !signal_pending(current)); + __set_current_state(TASK_RUNNING); + return t->task == NULL; } @@ -1378,7 +1406,7 @@ sys_nanosleep(struct timespec __user *rqtp, struct timespec __user *rmtp) /* * Functions related to boot-time initialization: */ -static void __devinit init_hrtimers_cpu(int cpu) +static void __cpuinit init_hrtimers_cpu(int cpu) { struct hrtimer_cpu_base *cpu_base = &per_cpu(hrtimer_bases, cpu); int i; @@ -1389,6 +1417,7 @@ static void __devinit init_hrtimers_cpu(int cpu) for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) cpu_base->clock_base[i].cpu_base = cpu_base; + INIT_LIST_HEAD(&cpu_base->cb_pending); hrtimer_init_hres(cpu_base); } diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 9b5dff6b3f6..44019ce30a1 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -297,18 +297,13 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc) if (unlikely(desc->status & IRQ_INPROGRESS)) goto out_unlock; + desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_cpu(cpu).irqs[irq]++; action = desc->action; - if (unlikely(!action || (desc->status & IRQ_DISABLED))) { - if (desc->chip->mask) - desc->chip->mask(irq); - desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); - desc->status |= IRQ_PENDING; + if (unlikely(!action || (desc->status & IRQ_DISABLED))) goto out_unlock; - } - desc->status &= ~(IRQ_REPLAY | IRQ_WAITING | IRQ_PENDING); desc->status |= IRQ_INPROGRESS; spin_unlock(&desc->lock); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 1f314221d53..438a0146428 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -479,6 +479,9 @@ void free_irq(unsigned int irq, void *dev_id) return; } printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq); +#ifdef CONFIG_DEBUG_SHIRQ + dump_stack(); +#endif spin_unlock_irqrestore(&desc->lock, flags); return; } diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index 50b81b98046..c2f2ccb0549 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -75,6 +75,18 @@ static int irq_affinity_write_proc(struct file *file, const char __user *buffer, #endif +static int irq_spurious_read(char *page, char **start, off_t off, + int count, int *eof, void *data) +{ + struct irq_desc *d = &irq_desc[(long) data]; + return sprintf(page, "count %u\n" + "unhandled %u\n" + "last_unhandled %u ms\n", + d->irq_count, + d->irqs_unhandled, + jiffies_to_msecs(d->last_unhandled)); +} + #define MAX_NAMELEN 128 static int name_unique(unsigned int irq, struct irqaction *new_action) @@ -118,6 +130,7 @@ void register_handler_proc(unsigned int irq, struct irqaction *action) void register_irq_proc(unsigned int irq) { char name [MAX_NAMELEN]; + struct proc_dir_entry *entry; if (!root_irq_dir || (irq_desc[irq].chip == &no_irq_chip) || @@ -132,8 +145,6 @@ void register_irq_proc(unsigned int irq) #ifdef CONFIG_SMP { - struct proc_dir_entry *entry; - /* create /proc/irq/<irq>/smp_affinity */ entry = create_proc_entry("smp_affinity", 0600, irq_desc[irq].dir); @@ -144,6 +155,12 @@ void register_irq_proc(unsigned int irq) } } #endif + + entry = create_proc_entry("spurious", 0444, irq_desc[irq].dir); + if (entry) { + entry->data = (void *)(long)irq; + entry->read_proc = irq_spurious_read; + } } #undef MAX_NAMELEN diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index 32b161972fa..a6b2bc831dd 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -10,6 +10,7 @@ #include <linux/module.h> #include <linux/kallsyms.h> #include <linux/interrupt.h> +#include <linux/moduleparam.h> static int irqfixup __read_mostly; @@ -225,6 +226,8 @@ int noirqdebug_setup(char *str) } __setup("noirqdebug", noirqdebug_setup); +module_param(noirqdebug, bool, 0644); +MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true"); static int __init irqfixup_setup(char *str) { @@ -236,6 +239,8 @@ static int __init irqfixup_setup(char *str) } __setup("irqfixup", irqfixup_setup); +module_param(irqfixup, int, 0644); +MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode 2: irqpoll mode"); static int __init irqpoll_setup(char *str) { diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index 2fc25810509..f091d13def0 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -53,14 +53,6 @@ static inline int is_kernel_inittext(unsigned long addr) return 0; } -static inline int is_kernel_extratext(unsigned long addr) -{ - if (addr >= (unsigned long)_sextratext - && addr <= (unsigned long)_eextratext) - return 1; - return 0; -} - static inline int is_kernel_text(unsigned long addr) { if (addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) @@ -80,8 +72,7 @@ static int is_ksym_addr(unsigned long addr) if (all_var) return is_kernel(addr); - return is_kernel_text(addr) || is_kernel_inittext(addr) || - is_kernel_extratext(addr); + return is_kernel_text(addr) || is_kernel_inittext(addr); } /* expand a compressed symbol data into the resulting uncompressed string, @@ -233,10 +224,11 @@ static unsigned long get_symbol_pos(unsigned long addr, int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize, unsigned long *offset) { + char namebuf[KSYM_NAME_LEN]; if (is_ksym_addr(addr)) return !!get_symbol_pos(addr, symbolsize, offset); - return !!module_address_lookup(addr, symbolsize, offset, NULL); + return !!module_address_lookup(addr, symbolsize, offset, NULL, namebuf); } /* @@ -251,8 +243,6 @@ const char *kallsyms_lookup(unsigned long addr, unsigned long *offset, char **modname, char *namebuf) { - const char *msym; - namebuf[KSYM_NAME_LEN - 1] = 0; namebuf[0] = 0; @@ -268,10 +258,8 @@ const char *kallsyms_lookup(unsigned long addr, } /* see if it's in a module */ - msym = module_address_lookup(addr, symbolsize, offset, modname); - if (msym) - return strncpy(namebuf, msym, KSYM_NAME_LEN - 1); - + return module_address_lookup(addr, symbolsize, offset, modname, + namebuf); return NULL; } diff --git a/kernel/kexec.c b/kernel/kexec.c index aa74a1ef2da..9a26eec9eb0 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -1404,6 +1404,7 @@ static int __init crash_save_vmcoreinfo_init(void) VMCOREINFO_OFFSET(list_head, next); VMCOREINFO_OFFSET(list_head, prev); VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER); + VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); VMCOREINFO_NUMBER(NR_FREE_PAGES); arch_crash_save_vmcoreinfo(); diff --git a/kernel/kmod.c b/kernel/kmod.c index c6a4f8aebeb..bb7df2a28bd 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -451,13 +451,11 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, enum umh_wait wait) { DECLARE_COMPLETION_ONSTACK(done); - int retval; + int retval = 0; helper_lock(); - if (sub_info->path[0] == '\0') { - retval = 0; + if (sub_info->path[0] == '\0') goto out; - } if (!khelper_wq || usermodehelper_disabled) { retval = -EBUSY; @@ -468,13 +466,14 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, sub_info->wait = wait; queue_work(khelper_wq, &sub_info->work); - if (wait == UMH_NO_WAIT) /* task has freed sub_info */ - return 0; + if (wait == UMH_NO_WAIT) /* task has freed sub_info */ + goto unlock; wait_for_completion(&done); retval = sub_info->retval; - out: +out: call_usermodehelper_freeinfo(sub_info); +unlock: helper_unlock(); return retval; } diff --git a/kernel/kprobes.c b/kernel/kprobes.c index e3a5d817ac9..7a86e643233 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -699,6 +699,12 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p, struct kretprobe_instance, uflist); ri->rp = rp; ri->task = current; + + if (rp->entry_handler && rp->entry_handler(ri, regs)) { + spin_unlock_irqrestore(&kretprobe_lock, flags); + return 0; + } + arch_prepare_kretprobe(ri, regs); /* XXX(hch): why is there no hlist_move_head? */ @@ -745,7 +751,8 @@ int __kprobes register_kretprobe(struct kretprobe *rp) INIT_HLIST_HEAD(&rp->used_instances); INIT_HLIST_HEAD(&rp->free_instances); for (i = 0; i < rp->maxactive; i++) { - inst = kmalloc(sizeof(struct kretprobe_instance), GFP_KERNEL); + inst = kmalloc(sizeof(struct kretprobe_instance) + + rp->data_size, GFP_KERNEL); if (inst == NULL) { free_rp_inst(rp); return -ENOMEM; @@ -824,6 +831,8 @@ static int __init init_kprobes(void) if (!err) err = register_die_notifier(&kprobe_exceptions_nb); + if (!err) + init_test_probes(); return err; } diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c index 65daa5373ca..e53bc30e9ba 100644 --- a/kernel/ksysfs.c +++ b/kernel/ksysfs.c @@ -17,30 +17,34 @@ #include <linux/sched.h> #define KERNEL_ATTR_RO(_name) \ -static struct subsys_attribute _name##_attr = __ATTR_RO(_name) +static struct kobj_attribute _name##_attr = __ATTR_RO(_name) #define KERNEL_ATTR_RW(_name) \ -static struct subsys_attribute _name##_attr = \ +static struct kobj_attribute _name##_attr = \ __ATTR(_name, 0644, _name##_show, _name##_store) #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) /* current uevent sequence number */ -static ssize_t uevent_seqnum_show(struct kset *kset, char *page) +static ssize_t uevent_seqnum_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { - return sprintf(page, "%llu\n", (unsigned long long)uevent_seqnum); + return sprintf(buf, "%llu\n", (unsigned long long)uevent_seqnum); } KERNEL_ATTR_RO(uevent_seqnum); /* uevent helper program, used during early boo */ -static ssize_t uevent_helper_show(struct kset *kset, char *page) +static ssize_t uevent_helper_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { - return sprintf(page, "%s\n", uevent_helper); + return sprintf(buf, "%s\n", uevent_helper); } -static ssize_t uevent_helper_store(struct kset *kset, const char *page, size_t count) +static ssize_t uevent_helper_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t count) { if (count+1 > UEVENT_HELPER_PATH_LEN) return -ENOENT; - memcpy(uevent_helper, page, count); + memcpy(uevent_helper, buf, count); uevent_helper[count] = '\0'; if (count && uevent_helper[count-1] == '\n') uevent_helper[count-1] = '\0'; @@ -50,21 +54,24 @@ KERNEL_ATTR_RW(uevent_helper); #endif #ifdef CONFIG_KEXEC -static ssize_t kexec_loaded_show(struct kset *kset, char *page) +static ssize_t kexec_loaded_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { - return sprintf(page, "%d\n", !!kexec_image); + return sprintf(buf, "%d\n", !!kexec_image); } KERNEL_ATTR_RO(kexec_loaded); -static ssize_t kexec_crash_loaded_show(struct kset *kset, char *page) +static ssize_t kexec_crash_loaded_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { - return sprintf(page, "%d\n", !!kexec_crash_image); + return sprintf(buf, "%d\n", !!kexec_crash_image); } KERNEL_ATTR_RO(kexec_crash_loaded); -static ssize_t vmcoreinfo_show(struct kset *kset, char *page) +static ssize_t vmcoreinfo_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) { - return sprintf(page, "%lx %x\n", + return sprintf(buf, "%lx %x\n", paddr_vmcoreinfo_note(), (unsigned int)vmcoreinfo_max_size); } @@ -94,8 +101,8 @@ static struct bin_attribute notes_attr = { .read = ¬es_read, }; -decl_subsys(kernel, NULL, NULL); -EXPORT_SYMBOL_GPL(kernel_subsys); +struct kobject *kernel_kobj; +EXPORT_SYMBOL_GPL(kernel_kobj); static struct attribute * kernel_attrs[] = { #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) @@ -116,24 +123,39 @@ static struct attribute_group kernel_attr_group = { static int __init ksysfs_init(void) { - int error = subsystem_register(&kernel_subsys); - if (!error) - error = sysfs_create_group(&kernel_subsys.kobj, - &kernel_attr_group); + int error; - if (!error && notes_size > 0) { - notes_attr.size = notes_size; - error = sysfs_create_bin_file(&kernel_subsys.kobj, - ¬es_attr); + kernel_kobj = kobject_create_and_add("kernel", NULL); + if (!kernel_kobj) { + error = -ENOMEM; + goto exit; } + error = sysfs_create_group(kernel_kobj, &kernel_attr_group); + if (error) + goto kset_exit; - /* - * Create "/sys/kernel/uids" directory and corresponding root user's - * directory under it. - */ - if (!error) - error = uids_kobject_init(); + if (notes_size > 0) { + notes_attr.size = notes_size; + error = sysfs_create_bin_file(kernel_kobj, ¬es_attr); + if (error) + goto group_exit; + } + /* create the /sys/kernel/uids/ directory */ + error = uids_sysfs_init(); + if (error) + goto notes_exit; + + return 0; + +notes_exit: + if (notes_size > 0) + sysfs_remove_bin_file(kernel_kobj, ¬es_attr); +group_exit: + sysfs_remove_group(kernel_kobj, &kernel_attr_group); +kset_exit: + kobject_put(kernel_kobj); +exit: return error; } diff --git a/kernel/kthread.c b/kernel/kthread.c index dcfe724300e..0ac887882f9 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -15,6 +15,8 @@ #include <linux/mutex.h> #include <asm/semaphore.h> +#define KTHREAD_NICE_LEVEL (-5) + static DEFINE_SPINLOCK(kthread_create_lock); static LIST_HEAD(kthread_create_list); struct task_struct *kthreadd_task; @@ -94,10 +96,18 @@ static void create_kthread(struct kthread_create_info *create) if (pid < 0) { create->result = ERR_PTR(pid); } else { + struct sched_param param = { .sched_priority = 0 }; wait_for_completion(&create->started); read_lock(&tasklist_lock); create->result = find_task_by_pid(pid); read_unlock(&tasklist_lock); + /* + * root may have changed our (kthreadd's) priority or CPU mask. + * The kernel thread should not inherit these properties. + */ + sched_setscheduler(create->result, SCHED_NORMAL, ¶m); + set_user_nice(create->result, KTHREAD_NICE_LEVEL); + set_cpus_allowed(create->result, CPU_MASK_ALL); } complete(&create->done); } @@ -221,7 +231,7 @@ int kthreadd(void *unused) /* Setup a clean context for our children to inherit. */ set_task_comm(tsk, "kthreadd"); ignore_signals(tsk); - set_user_nice(tsk, -5); + set_user_nice(tsk, KTHREAD_NICE_LEVEL); set_cpus_allowed(tsk, CPU_MASK_ALL); current->flags |= PF_NOFREEZE; diff --git a/kernel/latency.c b/kernel/latency.c deleted file mode 100644 index e63fcacb61a..00000000000 --- a/kernel/latency.c +++ /dev/null @@ -1,280 +0,0 @@ -/* - * latency.c: Explicit system-wide latency-expectation infrastructure - * - * The purpose of this infrastructure is to allow device drivers to set - * latency constraint they have and to collect and summarize these - * expectations globally. The cummulated result can then be used by - * power management and similar users to make decisions that have - * tradoffs with a latency component. - * - * An example user of this are the x86 C-states; each higher C state saves - * more power, but has a higher exit latency. For the idle loop power - * code to make a good decision which C-state to use, information about - * acceptable latencies is required. - * - * An example announcer of latency is an audio driver that knowns it - * will get an interrupt when the hardware has 200 usec of samples - * left in the DMA buffer; in that case the driver can set a latency - * constraint of, say, 150 usec. - * - * Multiple drivers can each announce their maximum accepted latency, - * to keep these appart, a string based identifier is used. - * - * - * (C) Copyright 2006 Intel Corporation - * Author: Arjan van de Ven <arjan@linux.intel.com> - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; version 2 - * of the License. - */ - -#include <linux/latency.h> -#include <linux/list.h> -#include <linux/spinlock.h> -#include <linux/slab.h> -#include <linux/module.h> -#include <linux/notifier.h> -#include <linux/jiffies.h> -#include <asm/atomic.h> - -struct latency_info { - struct list_head list; - int usecs; - char *identifier; -}; - -/* - * locking rule: all modifications to current_max_latency and - * latency_list need to be done while holding the latency_lock. - * latency_lock needs to be taken _irqsave. - */ -static atomic_t current_max_latency; -static DEFINE_SPINLOCK(latency_lock); - -static LIST_HEAD(latency_list); -static BLOCKING_NOTIFIER_HEAD(latency_notifier); - -/* - * This function returns the maximum latency allowed, which - * happens to be the minimum of all maximum latencies on the - * list. - */ -static int __find_max_latency(void) -{ - int min = INFINITE_LATENCY; - struct latency_info *info; - - list_for_each_entry(info, &latency_list, list) { - if (info->usecs < min) - min = info->usecs; - } - return min; -} - -/** - * set_acceptable_latency - sets the maximum latency acceptable - * @identifier: string that identifies this driver - * @usecs: maximum acceptable latency for this driver - * - * This function informs the kernel that this device(driver) - * can accept at most usecs latency. This setting is used for - * power management and similar tradeoffs. - * - * This function sleeps and can only be called from process - * context. - * Calling this function with an existing identifier is valid - * and will cause the existing latency setting to be changed. - */ -void set_acceptable_latency(char *identifier, int usecs) -{ - struct latency_info *info, *iter; - unsigned long flags; - int found_old = 0; - - info = kzalloc(sizeof(struct latency_info), GFP_KERNEL); - if (!info) - return; - info->usecs = usecs; - info->identifier = kstrdup(identifier, GFP_KERNEL); - if (!info->identifier) - goto free_info; - - spin_lock_irqsave(&latency_lock, flags); - list_for_each_entry(iter, &latency_list, list) { - if (strcmp(iter->identifier, identifier)==0) { - found_old = 1; - iter->usecs = usecs; - break; - } - } - if (!found_old) - list_add(&info->list, &latency_list); - - if (usecs < atomic_read(¤t_max_latency)) - atomic_set(¤t_max_latency, usecs); - - spin_unlock_irqrestore(&latency_lock, flags); - - blocking_notifier_call_chain(&latency_notifier, - atomic_read(¤t_max_latency), NULL); - - /* - * if we inserted the new one, we're done; otherwise there was - * an existing one so we need to free the redundant data - */ - if (!found_old) - return; - - kfree(info->identifier); -free_info: - kfree(info); -} -EXPORT_SYMBOL_GPL(set_acceptable_latency); - -/** - * modify_acceptable_latency - changes the maximum latency acceptable - * @identifier: string that identifies this driver - * @usecs: maximum acceptable latency for this driver - * - * This function informs the kernel that this device(driver) - * can accept at most usecs latency. This setting is used for - * power management and similar tradeoffs. - * - * This function does not sleep and can be called in any context. - * Trying to use a non-existing identifier silently gets ignored. - * - * Due to the atomic nature of this function, the modified latency - * value will only be used for future decisions; past decisions - * can still lead to longer latencies in the near future. - */ -void modify_acceptable_latency(char *identifier, int usecs) -{ - struct latency_info *iter; - unsigned long flags; - - spin_lock_irqsave(&latency_lock, flags); - list_for_each_entry(iter, &latency_list, list) { - if (strcmp(iter->identifier, identifier) == 0) { - iter->usecs = usecs; - break; - } - } - if (usecs < atomic_read(¤t_max_latency)) - atomic_set(¤t_max_latency, usecs); - spin_unlock_irqrestore(&latency_lock, flags); -} -EXPORT_SYMBOL_GPL(modify_acceptable_latency); - -/** - * remove_acceptable_latency - removes the maximum latency acceptable - * @identifier: string that identifies this driver - * - * This function removes a previously set maximum latency setting - * for the driver and frees up any resources associated with the - * bookkeeping needed for this. - * - * This function does not sleep and can be called in any context. - * Trying to use a non-existing identifier silently gets ignored. - */ -void remove_acceptable_latency(char *identifier) -{ - unsigned long flags; - int newmax = 0; - struct latency_info *iter, *temp; - - spin_lock_irqsave(&latency_lock, flags); - - list_for_each_entry_safe(iter, temp, &latency_list, list) { - if (strcmp(iter->identifier, identifier) == 0) { - list_del(&iter->list); - newmax = iter->usecs; - kfree(iter->identifier); - kfree(iter); - break; - } - } - - /* If we just deleted the system wide value, we need to - * recalculate with a full search - */ - if (newmax == atomic_read(¤t_max_latency)) { - newmax = __find_max_latency(); - atomic_set(¤t_max_latency, newmax); - } - spin_unlock_irqrestore(&latency_lock, flags); -} -EXPORT_SYMBOL_GPL(remove_acceptable_latency); - -/** - * system_latency_constraint - queries the system wide latency maximum - * - * This function returns the system wide maximum latency in - * microseconds. - * - * This function does not sleep and can be called in any context. - */ -int system_latency_constraint(void) -{ - return atomic_read(¤t_max_latency); -} -EXPORT_SYMBOL_GPL(system_latency_constraint); - -/** - * synchronize_acceptable_latency - recalculates all latency decisions - * - * This function will cause a callback to various kernel pieces that - * will make those pieces rethink their latency decisions. This implies - * that if there are overlong latencies in hardware state already, those - * latencies get taken right now. When this call completes no overlong - * latency decisions should be active anymore. - * - * Typical usecase of this is after a modify_acceptable_latency() call, - * which in itself is non-blocking and non-synchronizing. - * - * This function blocks and should not be called with locks held. - */ - -void synchronize_acceptable_latency(void) -{ - blocking_notifier_call_chain(&latency_notifier, - atomic_read(¤t_max_latency), NULL); -} -EXPORT_SYMBOL_GPL(synchronize_acceptable_latency); - -/* - * Latency notifier: this notifier gets called when a non-atomic new - * latency value gets set. The expectation nof the caller of the - * non-atomic set is that when the call returns, future latencies - * are within bounds, so the functions on the notifier list are - * expected to take the overlong latencies immediately, inside the - * callback, and not make a overlong latency decision anymore. - * - * The callback gets called when the new latency value is made - * active so system_latency_constraint() returns the new latency. - */ -int register_latency_notifier(struct notifier_block * nb) -{ - return blocking_notifier_chain_register(&latency_notifier, nb); -} -EXPORT_SYMBOL_GPL(register_latency_notifier); - -int unregister_latency_notifier(struct notifier_block * nb) -{ - return blocking_notifier_chain_unregister(&latency_notifier, nb); -} -EXPORT_SYMBOL_GPL(unregister_latency_notifier); - -static __init int latency_init(void) -{ - atomic_set(¤t_max_latency, INFINITE_LATENCY); - /* - * we don't want by default to have longer latencies than 2 ticks, - * since that would cause lost ticks - */ - set_acceptable_latency("kernel", 2*1000000/HZ); - return 0; -} - -module_init(latency_init); diff --git a/kernel/latencytop.c b/kernel/latencytop.c new file mode 100644 index 00000000000..b4e3c85abe7 --- /dev/null +++ b/kernel/latencytop.c @@ -0,0 +1,239 @@ +/* + * latencytop.c: Latency display infrastructure + * + * (C) Copyright 2008 Intel Corporation + * Author: Arjan van de Ven <arjan@linux.intel.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 + * of the License. + */ +#include <linux/latencytop.h> +#include <linux/kallsyms.h> +#include <linux/seq_file.h> +#include <linux/notifier.h> +#include <linux/spinlock.h> +#include <linux/proc_fs.h> +#include <linux/module.h> +#include <linux/sched.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/stacktrace.h> + +static DEFINE_SPINLOCK(latency_lock); + +#define MAXLR 128 +static struct latency_record latency_record[MAXLR]; + +int latencytop_enabled; + +void clear_all_latency_tracing(struct task_struct *p) +{ + unsigned long flags; + + if (!latencytop_enabled) + return; + + spin_lock_irqsave(&latency_lock, flags); + memset(&p->latency_record, 0, sizeof(p->latency_record)); + p->latency_record_count = 0; + spin_unlock_irqrestore(&latency_lock, flags); +} + +static void clear_global_latency_tracing(void) +{ + unsigned long flags; + + spin_lock_irqsave(&latency_lock, flags); + memset(&latency_record, 0, sizeof(latency_record)); + spin_unlock_irqrestore(&latency_lock, flags); +} + +static void __sched +account_global_scheduler_latency(struct task_struct *tsk, struct latency_record *lat) +{ + int firstnonnull = MAXLR + 1; + int i; + + if (!latencytop_enabled) + return; + + /* skip kernel threads for now */ + if (!tsk->mm) + return; + + for (i = 0; i < MAXLR; i++) { + int q; + int same = 1; + /* Nothing stored: */ + if (!latency_record[i].backtrace[0]) { + if (firstnonnull > i) + firstnonnull = i; + continue; + } + for (q = 0 ; q < LT_BACKTRACEDEPTH ; q++) { + if (latency_record[i].backtrace[q] != + lat->backtrace[q]) + same = 0; + if (same && lat->backtrace[q] == 0) + break; + if (same && lat->backtrace[q] == ULONG_MAX) + break; + } + if (same) { + latency_record[i].count++; + latency_record[i].time += lat->time; + if (lat->time > latency_record[i].max) + latency_record[i].max = lat->time; + return; + } + } + + i = firstnonnull; + if (i >= MAXLR - 1) + return; + + /* Allocted a new one: */ + memcpy(&latency_record[i], lat, sizeof(struct latency_record)); +} + +static inline void store_stacktrace(struct task_struct *tsk, struct latency_record *lat) +{ + struct stack_trace trace; + + memset(&trace, 0, sizeof(trace)); + trace.max_entries = LT_BACKTRACEDEPTH; + trace.entries = &lat->backtrace[0]; + trace.skip = 0; + save_stack_trace_tsk(tsk, &trace); +} + +void __sched +account_scheduler_latency(struct task_struct *tsk, int usecs, int inter) +{ + unsigned long flags; + int i, q; + struct latency_record lat; + + if (!latencytop_enabled) + return; + + /* Long interruptible waits are generally user requested... */ + if (inter && usecs > 5000) + return; + + memset(&lat, 0, sizeof(lat)); + lat.count = 1; + lat.time = usecs; + lat.max = usecs; + store_stacktrace(tsk, &lat); + + spin_lock_irqsave(&latency_lock, flags); + + account_global_scheduler_latency(tsk, &lat); + + /* + * short term hack; if we're > 32 we stop; future we recycle: + */ + tsk->latency_record_count++; + if (tsk->latency_record_count >= LT_SAVECOUNT) + goto out_unlock; + + for (i = 0; i < LT_SAVECOUNT ; i++) { + struct latency_record *mylat; + int same = 1; + mylat = &tsk->latency_record[i]; + for (q = 0 ; q < LT_BACKTRACEDEPTH ; q++) { + if (mylat->backtrace[q] != + lat.backtrace[q]) + same = 0; + if (same && lat.backtrace[q] == 0) + break; + if (same && lat.backtrace[q] == ULONG_MAX) + break; + } + if (same) { + mylat->count++; + mylat->time += lat.time; + if (lat.time > mylat->max) + mylat->max = lat.time; + goto out_unlock; + } + } + + /* Allocated a new one: */ + i = tsk->latency_record_count; + memcpy(&tsk->latency_record[i], &lat, sizeof(struct latency_record)); + +out_unlock: + spin_unlock_irqrestore(&latency_lock, flags); +} + +static int lstats_show(struct seq_file *m, void *v) +{ + int i; + + seq_puts(m, "Latency Top version : v0.1\n"); + + for (i = 0; i < MAXLR; i++) { + if (latency_record[i].backtrace[0]) { + int q; + seq_printf(m, "%i %li %li ", + latency_record[i].count, + latency_record[i].time, + latency_record[i].max); + for (q = 0; q < LT_BACKTRACEDEPTH; q++) { + char sym[KSYM_NAME_LEN]; + char *c; + if (!latency_record[i].backtrace[q]) + break; + if (latency_record[i].backtrace[q] == ULONG_MAX) + break; + sprint_symbol(sym, latency_record[i].backtrace[q]); + c = strchr(sym, '+'); + if (c) + *c = 0; + seq_printf(m, "%s ", sym); + } + seq_printf(m, "\n"); + } + } + return 0; +} + +static ssize_t +lstats_write(struct file *file, const char __user *buf, size_t count, + loff_t *offs) +{ + clear_global_latency_tracing(); + + return count; +} + +static int lstats_open(struct inode *inode, struct file *filp) +{ + return single_open(filp, lstats_show, NULL); +} + +static struct file_operations lstats_fops = { + .open = lstats_open, + .read = seq_read, + .write = lstats_write, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init init_lstats_procfs(void) +{ + struct proc_dir_entry *pe; + + pe = create_proc_entry("latency_stats", 0644, NULL); + if (!pe) + return -ENOMEM; + + pe->proc_fops = &lstats_fops; + + return 0; +} +__initcall(init_lstats_procfs); diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 723bd9f9255..3574379f4d6 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -2932,7 +2932,7 @@ static void zap_class(struct lock_class *class) } -static inline int within(void *addr, void *start, unsigned long size) +static inline int within(const void *addr, void *start, unsigned long size) { return addr >= start && addr < start + size; } @@ -2943,9 +2943,10 @@ void lockdep_free_key_range(void *start, unsigned long size) struct list_head *head; unsigned long flags; int i; + int locked; raw_local_irq_save(flags); - graph_lock(); + locked = graph_lock(); /* * Unhash all classes that were created by this module: @@ -2954,12 +2955,16 @@ void lockdep_free_key_range(void *start, unsigned long size) head = classhash_table + i; if (list_empty(head)) continue; - list_for_each_entry_safe(class, next, head, hash_entry) + list_for_each_entry_safe(class, next, head, hash_entry) { if (within(class->key, start, size)) zap_class(class); + else if (within(class->name, start, size)) + zap_class(class); + } } - graph_unlock(); + if (locked) + graph_unlock(); raw_local_irq_restore(flags); } @@ -2969,6 +2974,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) struct list_head *head; unsigned long flags; int i, j; + int locked; raw_local_irq_save(flags); @@ -2987,7 +2993,7 @@ void lockdep_reset_lock(struct lockdep_map *lock) * Debug check: in the end all mapped classes should * be gone. */ - graph_lock(); + locked = graph_lock(); for (i = 0; i < CLASSHASH_SIZE; i++) { head = classhash_table + i; if (list_empty(head)) @@ -3000,7 +3006,8 @@ void lockdep_reset_lock(struct lockdep_map *lock) } } } - graph_unlock(); + if (locked) + graph_unlock(); out_restore: raw_local_irq_restore(flags); @@ -3199,7 +3206,11 @@ retry: EXPORT_SYMBOL_GPL(debug_show_all_locks); -void debug_show_held_locks(struct task_struct *task) +/* + * Careful: only use this function if you are sure that + * the task cannot run in parallel! + */ +void __debug_show_held_locks(struct task_struct *task) { if (unlikely(!debug_locks)) { printk("INFO: lockdep is turned off.\n"); @@ -3207,6 +3218,12 @@ void debug_show_held_locks(struct task_struct *task) } lockdep_print_held_locks(task); } +EXPORT_SYMBOL_GPL(__debug_show_held_locks); + +void debug_show_held_locks(struct task_struct *task) +{ + __debug_show_held_locks(task); +} EXPORT_SYMBOL_GPL(debug_show_held_locks); diff --git a/kernel/module.c b/kernel/module.c index 91fe6958b6e..bd60278ee70 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -47,8 +47,6 @@ #include <asm/cacheflush.h> #include <linux/license.h> -extern int module_sysfs_initialized; - #if 0 #define DEBUGP printk #else @@ -67,6 +65,9 @@ extern int module_sysfs_initialized; static DEFINE_MUTEX(module_mutex); static LIST_HEAD(modules); +/* Waiting for a module to finish initializing? */ +static DECLARE_WAIT_QUEUE_HEAD(module_wq); + static BLOCKING_NOTIFIER_HEAD(module_notify_list); int register_module_notifier(struct notifier_block * nb) @@ -86,8 +87,11 @@ EXPORT_SYMBOL(unregister_module_notifier); static inline int strong_try_module_get(struct module *mod) { if (mod && mod->state == MODULE_STATE_COMING) + return -EBUSY; + if (try_module_get(mod)) return 0; - return try_module_get(mod); + else + return -ENOENT; } static inline void add_taint_module(struct module *mod, unsigned flag) @@ -426,6 +430,14 @@ static unsigned int find_pcpusec(Elf_Ehdr *hdr, return find_sec(hdr, sechdrs, secstrings, ".data.percpu"); } +static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size) +{ + int cpu; + + for_each_possible_cpu(cpu) + memcpy(pcpudest + per_cpu_offset(cpu), from, size); +} + static int percpu_modinit(void) { pcpu_num_used = 2; @@ -498,6 +510,8 @@ static struct module_attribute modinfo_##field = { \ MODINFO_ATTR(version); MODINFO_ATTR(srcversion); +static char last_unloaded_module[MODULE_NAME_LEN+1]; + #ifdef CONFIG_MODULE_UNLOAD /* Init the unload section of the module. */ static void module_unload_init(struct module *mod) @@ -539,11 +553,21 @@ static int already_uses(struct module *a, struct module *b) static int use_module(struct module *a, struct module *b) { struct module_use *use; - int no_warn; + int no_warn, err; if (b == NULL || already_uses(a, b)) return 1; - if (!strong_try_module_get(b)) + /* If we're interrupted or time out, we fail. */ + if (wait_event_interruptible_timeout( + module_wq, (err = strong_try_module_get(b)) != -EBUSY, + 30 * HZ) <= 0) { + printk("%s: gave up waiting for init of module %s.\n", + a->name, b->name); + return 0; + } + + /* If strong_try_module_get() returned a different error, we fail. */ + if (err) return 0; DEBUGP("Allocating new usage for %s.\n", a->name); @@ -721,6 +745,8 @@ sys_delete_module(const char __user *name_user, unsigned int flags) mod->exit(); mutex_lock(&module_mutex); } + /* Store the name of the last unloaded module for diagnostic purposes */ + strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); free_module(mod); out: @@ -814,7 +840,7 @@ static inline void module_unload_free(struct module *mod) static inline int use_module(struct module *a, struct module *b) { - return strong_try_module_get(b); + return strong_try_module_get(b) == 0; } static inline void module_unload_init(struct module *mod) @@ -1122,7 +1148,7 @@ static void add_notes_attrs(struct module *mod, unsigned int nsect, ++loaded; } - notes_attrs->dir = kobject_add_dir(&mod->mkobj.kobj, "notes"); + notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj); if (!notes_attrs->dir) goto out; @@ -1212,6 +1238,7 @@ void module_remove_modinfo_attrs(struct module *mod) int mod_sysfs_init(struct module *mod) { int err; + struct kobject *kobj; if (!module_sysfs_initialized) { printk(KERN_ERR "%s: module sysfs not initialized\n", @@ -1219,15 +1246,25 @@ int mod_sysfs_init(struct module *mod) err = -EINVAL; goto out; } - memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); - err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name); - if (err) + + kobj = kset_find_obj(module_kset, mod->name); + if (kobj) { + printk(KERN_ERR "%s: module is already loaded\n", mod->name); + kobject_put(kobj); + err = -EINVAL; goto out; - kobj_set_kset_s(&mod->mkobj, module_subsys); + } + mod->mkobj.mod = mod; - kobject_init(&mod->mkobj.kobj); + memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj)); + mod->mkobj.kobj.kset = module_kset; + err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL, + "%s", mod->name); + if (err) + kobject_put(&mod->mkobj.kobj); + /* delay uevent until full sysfs population */ out: return err; } @@ -1238,12 +1275,7 @@ int mod_sysfs_setup(struct module *mod, { int err; - /* delay uevent until full sysfs population */ - err = kobject_add(&mod->mkobj.kobj); - if (err) - goto out; - - mod->holders_dir = kobject_add_dir(&mod->mkobj.kobj, "holders"); + mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj); if (!mod->holders_dir) { err = -ENOMEM; goto out_unreg; @@ -1263,11 +1295,9 @@ int mod_sysfs_setup(struct module *mod, out_unreg_param: module_param_sysfs_remove(mod); out_unreg_holders: - kobject_unregister(mod->holders_dir); + kobject_put(mod->holders_dir); out_unreg: - kobject_del(&mod->mkobj.kobj); kobject_put(&mod->mkobj.kobj); -out: return err; } #endif @@ -1276,9 +1306,20 @@ static void mod_kobject_remove(struct module *mod) { module_remove_modinfo_attrs(mod); module_param_sysfs_remove(mod); - kobject_unregister(mod->mkobj.drivers_dir); - kobject_unregister(mod->holders_dir); - kobject_unregister(&mod->mkobj.kobj); + kobject_put(mod->mkobj.drivers_dir); + kobject_put(mod->holders_dir); + kobject_put(&mod->mkobj.kobj); +} + +/* + * link the module with the whole machine is stopped with interrupts off + * - this defends against kallsyms not taking locks + */ +static int __link_module(void *_mod) +{ + struct module *mod = _mod; + list_add(&mod->list, &modules); + return 0; } /* @@ -1330,7 +1371,7 @@ void *__symbol_get(const char *symbol) preempt_disable(); value = __find_symbol(symbol, &owner, &crc, 1); - if (value && !strong_try_module_get(owner)) + if (value && strong_try_module_get(owner) != 0) value = 0; preempt_enable(); @@ -1884,16 +1925,16 @@ static struct module *load_module(void __user *umod, /* Now we've moved module, initialize linked lists, etc. */ module_unload_init(mod); - /* Initialize kobject, so we can reference it. */ + /* add kobject, so we can reference it. */ err = mod_sysfs_init(mod); if (err) - goto cleanup; + goto free_unload; /* Set up license info based on the info section */ set_license(mod, get_modinfo(sechdrs, infoindex, "license")); if (strcmp(mod->name, "ndiswrapper") == 0) - add_taint(TAINT_PROPRIETARY_MODULE); + add_taint_module(mod, TAINT_PROPRIETARY_MODULE); if (strcmp(mod->name, "driverloader") == 0) add_taint_module(mod, TAINT_PROPRIETARY_MODULE); @@ -2023,6 +2064,11 @@ static struct module *load_module(void __user *umod, printk(KERN_WARNING "%s: Ignoring obsolete parameters\n", mod->name); + /* Now sew it into the lists so we can get lockdep and oops + * info during argument parsing. Noone should access us, since + * strong_try_module_get() will fail. */ + stop_machine_run(__link_module, mod, NR_CPUS); + /* Size of section 0 is 0, so this works well if no params */ err = parse_args(mod->name, mod->args, (struct kernel_param *) @@ -2031,7 +2077,7 @@ static struct module *load_module(void __user *umod, / sizeof(struct kernel_param), NULL); if (err < 0) - goto arch_cleanup; + goto unlink; err = mod_sysfs_setup(mod, (struct kernel_param *) @@ -2039,7 +2085,7 @@ static struct module *load_module(void __user *umod, sechdrs[setupindex].sh_size / sizeof(struct kernel_param)); if (err < 0) - goto arch_cleanup; + goto unlink; add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs); add_notes_attrs(mod, hdr->e_shnum, secstrings, sechdrs); @@ -2054,9 +2100,13 @@ static struct module *load_module(void __user *umod, /* Done! */ return mod; - arch_cleanup: + unlink: + stop_machine_run(__unlink_module, mod, NR_CPUS); module_arch_cleanup(mod); cleanup: + kobject_del(&mod->mkobj.kobj); + kobject_put(&mod->mkobj.kobj); + free_unload: module_unload_free(mod); module_free(mod, mod->module_init); free_core: @@ -2076,17 +2126,6 @@ static struct module *load_module(void __user *umod, goto free_hdr; } -/* - * link the module with the whole machine is stopped with interrupts off - * - this defends against kallsyms not taking locks - */ -static int __link_module(void *_mod) -{ - struct module *mod = _mod; - list_add(&mod->list, &modules); - return 0; -} - /* This is where the real work happens */ asmlinkage long sys_init_module(void __user *umod, @@ -2111,10 +2150,6 @@ sys_init_module(void __user *umod, return PTR_ERR(mod); } - /* Now sew it into the lists. They won't access us, since - strong_try_module_get() will fail. */ - stop_machine_run(__link_module, mod, NR_CPUS); - /* Drop lock so they can recurse */ mutex_unlock(&module_mutex); @@ -2133,6 +2168,7 @@ sys_init_module(void __user *umod, mutex_lock(&module_mutex); free_module(mod); mutex_unlock(&module_mutex); + wake_up(&module_wq); return ret; } @@ -2147,6 +2183,7 @@ sys_init_module(void __user *umod, mod->init_size = 0; mod->init_text_size = 0; mutex_unlock(&module_mutex); + wake_up(&module_wq); return 0; } @@ -2211,32 +2248,41 @@ static const char *get_ksymbol(struct module *mod, return mod->strtab + mod->symtab[best].st_name; } -/* For kallsyms to ask for address resolution. NULL means not found. - We don't lock, as this is used for oops resolution and races are a - lesser concern. */ -const char *module_address_lookup(unsigned long addr, - unsigned long *size, - unsigned long *offset, - char **modname) +/* For kallsyms to ask for address resolution. NULL means not found. Careful + * not to lock to avoid deadlock on oopses, simply disable preemption. */ +char *module_address_lookup(unsigned long addr, + unsigned long *size, + unsigned long *offset, + char **modname, + char *namebuf) { struct module *mod; + const char *ret = NULL; + preempt_disable(); list_for_each_entry(mod, &modules, list) { if (within(addr, mod->module_init, mod->init_size) || within(addr, mod->module_core, mod->core_size)) { if (modname) *modname = mod->name; - return get_ksymbol(mod, addr, size, offset); + ret = get_ksymbol(mod, addr, size, offset); + break; } } - return NULL; + /* Make a copy in here where it's safe */ + if (ret) { + strncpy(namebuf, ret, KSYM_NAME_LEN - 1); + ret = namebuf; + } + preempt_enable(); + return (char *)ret; } int lookup_module_symbol_name(unsigned long addr, char *symname) { struct module *mod; - mutex_lock(&module_mutex); + preempt_disable(); list_for_each_entry(mod, &modules, list) { if (within(addr, mod->module_init, mod->init_size) || within(addr, mod->module_core, mod->core_size)) { @@ -2246,12 +2292,12 @@ int lookup_module_symbol_name(unsigned long addr, char *symname) if (!sym) goto out; strlcpy(symname, sym, KSYM_NAME_LEN); - mutex_unlock(&module_mutex); + preempt_enable(); return 0; } } out: - mutex_unlock(&module_mutex); + preempt_enable(); return -ERANGE; } @@ -2260,7 +2306,7 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, { struct module *mod; - mutex_lock(&module_mutex); + preempt_disable(); list_for_each_entry(mod, &modules, list) { if (within(addr, mod->module_init, mod->init_size) || within(addr, mod->module_core, mod->core_size)) { @@ -2273,12 +2319,12 @@ int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size, strlcpy(modname, mod->name, MODULE_NAME_LEN); if (name) strlcpy(name, sym, KSYM_NAME_LEN); - mutex_unlock(&module_mutex); + preempt_enable(); return 0; } } out: - mutex_unlock(&module_mutex); + preempt_enable(); return -ERANGE; } @@ -2287,7 +2333,7 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, { struct module *mod; - mutex_lock(&module_mutex); + preempt_disable(); list_for_each_entry(mod, &modules, list) { if (symnum < mod->num_symtab) { *value = mod->symtab[symnum].st_value; @@ -2296,12 +2342,12 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, KSYM_NAME_LEN); strlcpy(module_name, mod->name, MODULE_NAME_LEN); *exported = is_exported(name, mod); - mutex_unlock(&module_mutex); + preempt_enable(); return 0; } symnum -= mod->num_symtab; } - mutex_unlock(&module_mutex); + preempt_enable(); return -ERANGE; } @@ -2324,6 +2370,7 @@ unsigned long module_kallsyms_lookup_name(const char *name) unsigned long ret = 0; /* Don't lock: we're in enough trouble already. */ + preempt_disable(); if ((colon = strchr(name, ':')) != NULL) { *colon = '\0'; if ((mod = find_module(name)) != NULL) @@ -2334,6 +2381,7 @@ unsigned long module_kallsyms_lookup_name(const char *name) if ((ret = mod_find_symname(mod, name)) != 0) break; } + preempt_enable(); return ret; } #endif /* CONFIG_KALLSYMS */ @@ -2355,21 +2403,30 @@ static void m_stop(struct seq_file *m, void *p) mutex_unlock(&module_mutex); } -static char *taint_flags(unsigned int taints, char *buf) +static char *module_flags(struct module *mod, char *buf) { int bx = 0; - if (taints) { + if (mod->taints || + mod->state == MODULE_STATE_GOING || + mod->state == MODULE_STATE_COMING) { buf[bx++] = '('; - if (taints & TAINT_PROPRIETARY_MODULE) + if (mod->taints & TAINT_PROPRIETARY_MODULE) buf[bx++] = 'P'; - if (taints & TAINT_FORCED_MODULE) + if (mod->taints & TAINT_FORCED_MODULE) buf[bx++] = 'F'; /* * TAINT_FORCED_RMMOD: could be added. * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't * apply to modules. */ + + /* Show a - for module-is-being-unloaded */ + if (mod->state == MODULE_STATE_GOING) + buf[bx++] = '-'; + /* Show a + for module-is-being-loaded */ + if (mod->state == MODULE_STATE_COMING) + buf[bx++] = '+'; buf[bx++] = ')'; } buf[bx] = '\0'; @@ -2396,7 +2453,7 @@ static int m_show(struct seq_file *m, void *p) /* Taints info */ if (mod->taints) - seq_printf(m, " %s", taint_flags(mod->taints, buf)); + seq_printf(m, " %s", module_flags(mod, buf)); seq_printf(m, "\n"); return 0; @@ -2491,97 +2548,12 @@ void print_modules(void) printk("Modules linked in:"); list_for_each_entry(mod, &modules, list) - printk(" %s%s", mod->name, taint_flags(mod->taints, buf)); + printk(" %s%s", mod->name, module_flags(mod, buf)); + if (last_unloaded_module[0]) + printk(" [last unloaded: %s]", last_unloaded_module); printk("\n"); } -#ifdef CONFIG_SYSFS -static char *make_driver_name(struct device_driver *drv) -{ - char *driver_name; - - driver_name = kmalloc(strlen(drv->name) + strlen(drv->bus->name) + 2, - GFP_KERNEL); - if (!driver_name) - return NULL; - - sprintf(driver_name, "%s:%s", drv->bus->name, drv->name); - return driver_name; -} - -static void module_create_drivers_dir(struct module_kobject *mk) -{ - if (!mk || mk->drivers_dir) - return; - - mk->drivers_dir = kobject_add_dir(&mk->kobj, "drivers"); -} - -void module_add_driver(struct module *mod, struct device_driver *drv) -{ - char *driver_name; - int no_warn; - struct module_kobject *mk = NULL; - - if (!drv) - return; - - if (mod) - mk = &mod->mkobj; - else if (drv->mod_name) { - struct kobject *mkobj; - - /* Lookup built-in module entry in /sys/modules */ - mkobj = kset_find_obj(&module_subsys, drv->mod_name); - if (mkobj) { - mk = container_of(mkobj, struct module_kobject, kobj); - /* remember our module structure */ - drv->mkobj = mk; - /* kset_find_obj took a reference */ - kobject_put(mkobj); - } - } - - if (!mk) - return; - - /* Don't check return codes; these calls are idempotent */ - no_warn = sysfs_create_link(&drv->kobj, &mk->kobj, "module"); - driver_name = make_driver_name(drv); - if (driver_name) { - module_create_drivers_dir(mk); - no_warn = sysfs_create_link(mk->drivers_dir, &drv->kobj, - driver_name); - kfree(driver_name); - } -} -EXPORT_SYMBOL(module_add_driver); - -void module_remove_driver(struct device_driver *drv) -{ - struct module_kobject *mk = NULL; - char *driver_name; - - if (!drv) - return; - - sysfs_remove_link(&drv->kobj, "module"); - - if (drv->owner) - mk = &drv->owner->mkobj; - else if (drv->mkobj) - mk = drv->mkobj; - if (mk && mk->drivers_dir) { - driver_name = make_driver_name(drv); - if (driver_name) { - sysfs_remove_link(mk->drivers_dir, driver_name); - kfree(driver_name); - } - } -} -EXPORT_SYMBOL(module_remove_driver); -#endif - #ifdef CONFIG_MODVERSIONS /* Generate the signature for struct module here, too, for modversions. */ void struct_module(struct module *mod) { return; } diff --git a/kernel/mutex.c b/kernel/mutex.c index d7fe50cc556..d9ec9b66625 100644 --- a/kernel/mutex.c +++ b/kernel/mutex.c @@ -166,9 +166,12 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, * got a signal? (This code gets eliminated in the * TASK_UNINTERRUPTIBLE case.) */ - if (unlikely(state == TASK_INTERRUPTIBLE && - signal_pending(task))) { - mutex_remove_waiter(lock, &waiter, task_thread_info(task)); + if (unlikely((state == TASK_INTERRUPTIBLE && + signal_pending(task)) || + (state == TASK_KILLABLE && + fatal_signal_pending(task)))) { + mutex_remove_waiter(lock, &waiter, + task_thread_info(task)); mutex_release(&lock->dep_map, 1, ip); spin_unlock_mutex(&lock->wait_lock, flags); @@ -211,6 +214,14 @@ mutex_lock_nested(struct mutex *lock, unsigned int subclass) EXPORT_SYMBOL_GPL(mutex_lock_nested); int __sched +mutex_lock_killable_nested(struct mutex *lock, unsigned int subclass) +{ + might_sleep(); + return __mutex_lock_common(lock, TASK_KILLABLE, subclass, _RET_IP_); +} +EXPORT_SYMBOL_GPL(mutex_lock_killable_nested); + +int __sched mutex_lock_interruptible_nested(struct mutex *lock, unsigned int subclass) { might_sleep(); @@ -272,6 +283,9 @@ __mutex_unlock_slowpath(atomic_t *lock_count) * mutex_lock_interruptible() and mutex_trylock(). */ static int fastcall noinline __sched +__mutex_lock_killable_slowpath(atomic_t *lock_count); + +static noinline int fastcall __sched __mutex_lock_interruptible_slowpath(atomic_t *lock_count); /*** @@ -294,6 +308,14 @@ int fastcall __sched mutex_lock_interruptible(struct mutex *lock) EXPORT_SYMBOL(mutex_lock_interruptible); +int fastcall __sched mutex_lock_killable(struct mutex *lock) +{ + might_sleep(); + return __mutex_fastpath_lock_retval + (&lock->count, __mutex_lock_killable_slowpath); +} +EXPORT_SYMBOL(mutex_lock_killable); + static void fastcall noinline __sched __mutex_lock_slowpath(atomic_t *lock_count) { @@ -303,6 +325,14 @@ __mutex_lock_slowpath(atomic_t *lock_count) } static int fastcall noinline __sched +__mutex_lock_killable_slowpath(atomic_t *lock_count) +{ + struct mutex *lock = container_of(lock_count, struct mutex, count); + + return __mutex_lock_common(lock, TASK_KILLABLE, 0, _RET_IP_); +} + +static noinline int fastcall __sched __mutex_lock_interruptible_slowpath(atomic_t *lock_count) { struct mutex *lock = container_of(lock_count, struct mutex, count); diff --git a/kernel/notifier.c b/kernel/notifier.c index 4253f472f06..643360d1bb1 100644 --- a/kernel/notifier.c +++ b/kernel/notifier.c @@ -4,6 +4,7 @@ #include <linux/notifier.h> #include <linux/rcupdate.h> #include <linux/vmalloc.h> +#include <linux/reboot.h> /* * Notifier list for kernel code which wants to be called diff --git a/kernel/panic.c b/kernel/panic.c index 6f6e03e9159..d9e90cfe329 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -19,6 +19,8 @@ #include <linux/nmi.h> #include <linux/kexec.h> #include <linux/debug_locks.h> +#include <linux/random.h> +#include <linux/kallsyms.h> int panic_on_oops; int tainted; @@ -266,13 +268,52 @@ void oops_enter(void) } /* + * 64-bit random ID for oopses: + */ +static u64 oops_id; + +static int init_oops_id(void) +{ + if (!oops_id) + get_random_bytes(&oops_id, sizeof(oops_id)); + + return 0; +} +late_initcall(init_oops_id); + +static void print_oops_end_marker(void) +{ + init_oops_id(); + printk(KERN_WARNING "---[ end trace %016llx ]---\n", + (unsigned long long)oops_id); +} + +/* * Called when the architecture exits its oops handler, after printing * everything. */ void oops_exit(void) { do_oops_enter_exit(); + print_oops_end_marker(); +} + +#ifdef WANT_WARN_ON_SLOWPATH +void warn_on_slowpath(const char *file, int line) +{ + char function[KSYM_SYMBOL_LEN]; + unsigned long caller = (unsigned long) __builtin_return_address(0); + sprint_symbol(function, caller); + + printk(KERN_WARNING "------------[ cut here ]------------\n"); + printk(KERN_WARNING "WARNING: at %s:%d %s()\n", file, + line, function); + print_modules(); + dump_stack(); + print_oops_end_marker(); } +EXPORT_SYMBOL(warn_on_slowpath); +#endif #ifdef CONFIG_CC_STACKPROTECTOR /* diff --git a/kernel/params.c b/kernel/params.c index 2a4c51487e7..e28c70628bb 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -272,7 +272,7 @@ static int param_array(const char *name, unsigned int min, unsigned int max, void *elem, int elemsize, int (*set)(const char *, struct kernel_param *kp), - int *num) + unsigned int *num) { int ret; struct kernel_param kp; @@ -376,8 +376,6 @@ int param_get_string(char *buffer, struct kernel_param *kp) extern struct kernel_param __start___param[], __stop___param[]; -#define MAX_KBUILD_MODNAME KOBJ_NAME_LEN - struct param_attribute { struct module_attribute mattr; @@ -472,7 +470,7 @@ param_sysfs_setup(struct module_kobject *mk, sizeof(mp->grp.attrs[0])); size[1] = (valid_attrs + 1) * sizeof(mp->grp.attrs[0]); - mp = kmalloc(size[0] + size[1], GFP_KERNEL); + mp = kzalloc(size[0] + size[1], GFP_KERNEL); if (!mp) return ERR_PTR(-ENOMEM); @@ -560,11 +558,10 @@ static void __init kernel_param_sysfs_setup(const char *name, BUG_ON(!mk); mk->mod = THIS_MODULE; - kobj_set_kset_s(mk, module_subsys); - kobject_set_name(&mk->kobj, name); - kobject_init(&mk->kobj); - ret = kobject_add(&mk->kobj); + mk->kobj.kset = module_kset; + ret = kobject_init_and_add(&mk->kobj, &module_ktype, NULL, "%s", name); if (ret) { + kobject_put(&mk->kobj); printk(KERN_ERR "Module '%s' failed to be added to sysfs, " "error number %d\n", name, ret); printk(KERN_ERR "The system will be unstable now.\n"); @@ -588,7 +585,7 @@ static void __init param_sysfs_builtin(void) { struct kernel_param *kp, *kp_begin = NULL; unsigned int i, name_len, count = 0; - char modname[MAX_KBUILD_MODNAME + 1] = ""; + char modname[MODULE_NAME_LEN + 1] = ""; for (i=0; i < __stop___param - __start___param; i++) { char *dot; @@ -596,12 +593,12 @@ static void __init param_sysfs_builtin(void) kp = &__start___param[i]; max_name_len = - min_t(size_t, MAX_KBUILD_MODNAME, strlen(kp->name)); + min_t(size_t, MODULE_NAME_LEN, strlen(kp->name)); dot = memchr(kp->name, '.', max_name_len); if (!dot) { DEBUGP("couldn't find period in first %d characters " - "of %s\n", MAX_KBUILD_MODNAME, kp->name); + "of %s\n", MODULE_NAME_LEN, kp->name); continue; } name_len = dot - kp->name; @@ -679,8 +676,6 @@ static struct sysfs_ops module_sysfs_ops = { .store = module_attr_store, }; -static struct kobj_type module_ktype; - static int uevent_filter(struct kset *kset, struct kobject *kobj) { struct kobj_type *ktype = get_ktype(kobj); @@ -694,10 +689,10 @@ static struct kset_uevent_ops module_uevent_ops = { .filter = uevent_filter, }; -decl_subsys(module, &module_ktype, &module_uevent_ops); +struct kset *module_kset; int module_sysfs_initialized; -static struct kobj_type module_ktype = { +struct kobj_type module_ktype = { .sysfs_ops = &module_sysfs_ops, }; @@ -706,13 +701,11 @@ static struct kobj_type module_ktype = { */ static int __init param_sysfs_init(void) { - int ret; - - ret = subsystem_register(&module_subsys); - if (ret < 0) { - printk(KERN_WARNING "%s (%d): subsystem_register error: %d\n", - __FILE__, __LINE__, ret); - return ret; + module_kset = kset_create_and_add("module", &module_uevent_ops, NULL); + if (!module_kset) { + printk(KERN_WARNING "%s (%d): error creating kset\n", + __FILE__, __LINE__); + return -ENOMEM; } module_sysfs_initialized = 1; @@ -722,14 +715,7 @@ static int __init param_sysfs_init(void) } subsys_initcall(param_sysfs_init); -#else -#if 0 -static struct sysfs_ops module_sysfs_ops = { - .show = NULL, - .store = NULL, -}; -#endif -#endif +#endif /* CONFIG_SYSFS */ EXPORT_SYMBOL(param_set_byte); EXPORT_SYMBOL(param_get_byte); diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c new file mode 100644 index 00000000000..0afe32be4c8 --- /dev/null +++ b/kernel/pm_qos_params.c @@ -0,0 +1,425 @@ +/* + * This module exposes the interface to kernel space for specifying + * QoS dependencies. It provides infrastructure for registration of: + * + * Dependents on a QoS value : register requirements + * Watchers of QoS value : get notified when target QoS value changes + * + * This QoS design is best effort based. Dependents register their QoS needs. + * Watchers register to keep track of the current QoS needs of the system. + * + * There are 3 basic classes of QoS parameter: latency, timeout, throughput + * each have defined units: + * latency: usec + * timeout: usec <-- currently not used. + * throughput: kbs (kilo byte / sec) + * + * There are lists of pm_qos_objects each one wrapping requirements, notifiers + * + * User mode requirements on a QOS parameter register themselves to the + * subsystem by opening the device node /dev/... and writing there request to + * the node. As long as the process holds a file handle open to the node the + * client continues to be accounted for. Upon file release the usermode + * requirement is removed and a new qos target is computed. This way when the + * requirement that the application has is cleaned up when closes the file + * pointer or exits the pm_qos_object will get an opportunity to clean up. + * + * mark gross mgross@linux.intel.com + */ + +#include <linux/pm_qos_params.h> +#include <linux/sched.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/time.h> +#include <linux/fs.h> +#include <linux/device.h> +#include <linux/miscdevice.h> +#include <linux/string.h> +#include <linux/platform_device.h> +#include <linux/init.h> + +#include <linux/uaccess.h> + +/* + * locking rule: all changes to target_value or requirements or notifiers lists + * or pm_qos_object list and pm_qos_objects need to happen with pm_qos_lock + * held, taken with _irqsave. One lock to rule them all + */ +struct requirement_list { + struct list_head list; + union { + s32 value; + s32 usec; + s32 kbps; + }; + char *name; +}; + +static s32 max_compare(s32 v1, s32 v2); +static s32 min_compare(s32 v1, s32 v2); + +struct pm_qos_object { + struct requirement_list requirements; + struct blocking_notifier_head *notifiers; + struct miscdevice pm_qos_power_miscdev; + char *name; + s32 default_value; + s32 target_value; + s32 (*comparitor)(s32, s32); +}; + +static struct pm_qos_object null_pm_qos; +static BLOCKING_NOTIFIER_HEAD(cpu_dma_lat_notifier); +static struct pm_qos_object cpu_dma_pm_qos = { + .requirements = {LIST_HEAD_INIT(cpu_dma_pm_qos.requirements.list)}, + .notifiers = &cpu_dma_lat_notifier, + .name = "cpu_dma_latency", + .default_value = 2000 * USEC_PER_SEC, + .target_value = 2000 * USEC_PER_SEC, + .comparitor = min_compare +}; + +static BLOCKING_NOTIFIER_HEAD(network_lat_notifier); +static struct pm_qos_object network_lat_pm_qos = { + .requirements = {LIST_HEAD_INIT(network_lat_pm_qos.requirements.list)}, + .notifiers = &network_lat_notifier, + .name = "network_latency", + .default_value = 2000 * USEC_PER_SEC, + .target_value = 2000 * USEC_PER_SEC, + .comparitor = min_compare +}; + + +static BLOCKING_NOTIFIER_HEAD(network_throughput_notifier); +static struct pm_qos_object network_throughput_pm_qos = { + .requirements = + {LIST_HEAD_INIT(network_throughput_pm_qos.requirements.list)}, + .notifiers = &network_throughput_notifier, + .name = "network_throughput", + .default_value = 0, + .target_value = 0, + .comparitor = max_compare +}; + + +static struct pm_qos_object *pm_qos_array[] = { + &null_pm_qos, + &cpu_dma_pm_qos, + &network_lat_pm_qos, + &network_throughput_pm_qos +}; + +static DEFINE_SPINLOCK(pm_qos_lock); + +static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos); +static int pm_qos_power_open(struct inode *inode, struct file *filp); +static int pm_qos_power_release(struct inode *inode, struct file *filp); + +static const struct file_operations pm_qos_power_fops = { + .write = pm_qos_power_write, + .open = pm_qos_power_open, + .release = pm_qos_power_release, +}; + +/* static helper functions */ +static s32 max_compare(s32 v1, s32 v2) +{ + return max(v1, v2); +} + +static s32 min_compare(s32 v1, s32 v2) +{ + return min(v1, v2); +} + + +static void update_target(int target) +{ + s32 extreme_value; + struct requirement_list *node; + unsigned long flags; + int call_notifier = 0; + + spin_lock_irqsave(&pm_qos_lock, flags); + extreme_value = pm_qos_array[target]->default_value; + list_for_each_entry(node, + &pm_qos_array[target]->requirements.list, list) { + extreme_value = pm_qos_array[target]->comparitor( + extreme_value, node->value); + } + if (pm_qos_array[target]->target_value != extreme_value) { + call_notifier = 1; + pm_qos_array[target]->target_value = extreme_value; + pr_debug(KERN_ERR "new target for qos %d is %d\n", target, + pm_qos_array[target]->target_value); + } + spin_unlock_irqrestore(&pm_qos_lock, flags); + + if (call_notifier) + blocking_notifier_call_chain(pm_qos_array[target]->notifiers, + (unsigned long) extreme_value, NULL); +} + +static int register_pm_qos_misc(struct pm_qos_object *qos) +{ + qos->pm_qos_power_miscdev.minor = MISC_DYNAMIC_MINOR; + qos->pm_qos_power_miscdev.name = qos->name; + qos->pm_qos_power_miscdev.fops = &pm_qos_power_fops; + + return misc_register(&qos->pm_qos_power_miscdev); +} + +static int find_pm_qos_object_by_minor(int minor) +{ + int pm_qos_class; + + for (pm_qos_class = 0; + pm_qos_class < PM_QOS_NUM_CLASSES; pm_qos_class++) { + if (minor == + pm_qos_array[pm_qos_class]->pm_qos_power_miscdev.minor) + return pm_qos_class; + } + return -1; +} + +/** + * pm_qos_requirement - returns current system wide qos expectation + * @pm_qos_class: identification of which qos value is requested + * + * This function returns the current target value in an atomic manner. + */ +int pm_qos_requirement(int pm_qos_class) +{ + int ret_val; + unsigned long flags; + + spin_lock_irqsave(&pm_qos_lock, flags); + ret_val = pm_qos_array[pm_qos_class]->target_value; + spin_unlock_irqrestore(&pm_qos_lock, flags); + + return ret_val; +} +EXPORT_SYMBOL_GPL(pm_qos_requirement); + +/** + * pm_qos_add_requirement - inserts new qos request into the list + * @pm_qos_class: identifies which list of qos request to us + * @name: identifies the request + * @value: defines the qos request + * + * This function inserts a new entry in the pm_qos_class list of requested qos + * performance charactoistics. It recomputes the agregate QoS expectations for + * the pm_qos_class of parrameters. + */ +int pm_qos_add_requirement(int pm_qos_class, char *name, s32 value) +{ + struct requirement_list *dep; + unsigned long flags; + + dep = kzalloc(sizeof(struct requirement_list), GFP_KERNEL); + if (dep) { + if (value == PM_QOS_DEFAULT_VALUE) + dep->value = pm_qos_array[pm_qos_class]->default_value; + else + dep->value = value; + dep->name = kstrdup(name, GFP_KERNEL); + if (!dep->name) + goto cleanup; + + spin_lock_irqsave(&pm_qos_lock, flags); + list_add(&dep->list, + &pm_qos_array[pm_qos_class]->requirements.list); + spin_unlock_irqrestore(&pm_qos_lock, flags); + update_target(pm_qos_class); + + return 0; + } + +cleanup: + kfree(dep); + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(pm_qos_add_requirement); + +/** + * pm_qos_update_requirement - modifies an existing qos request + * @pm_qos_class: identifies which list of qos request to us + * @name: identifies the request + * @value: defines the qos request + * + * Updates an existing qos requierement for the pm_qos_class of parameters along + * with updating the target pm_qos_class value. + * + * If the named request isn't in the lest then no change is made. + */ +int pm_qos_update_requirement(int pm_qos_class, char *name, s32 new_value) +{ + unsigned long flags; + struct requirement_list *node; + int pending_update = 0; + + spin_lock_irqsave(&pm_qos_lock, flags); + list_for_each_entry(node, + &pm_qos_array[pm_qos_class]->requirements.list, list) { + if (strcmp(node->name, name) == 0) { + if (new_value == PM_QOS_DEFAULT_VALUE) + node->value = + pm_qos_array[pm_qos_class]->default_value; + else + node->value = new_value; + pending_update = 1; + break; + } + } + spin_unlock_irqrestore(&pm_qos_lock, flags); + if (pending_update) + update_target(pm_qos_class); + + return 0; +} +EXPORT_SYMBOL_GPL(pm_qos_update_requirement); + +/** + * pm_qos_remove_requirement - modifies an existing qos request + * @pm_qos_class: identifies which list of qos request to us + * @name: identifies the request + * + * Will remove named qos request from pm_qos_class list of parrameters and + * recompute the current target value for the pm_qos_class. + */ +void pm_qos_remove_requirement(int pm_qos_class, char *name) +{ + unsigned long flags; + struct requirement_list *node; + int pending_update = 0; + + spin_lock_irqsave(&pm_qos_lock, flags); + list_for_each_entry(node, + &pm_qos_array[pm_qos_class]->requirements.list, list) { + if (strcmp(node->name, name) == 0) { + kfree(node->name); + list_del(&node->list); + kfree(node); + pending_update = 1; + break; + } + } + spin_unlock_irqrestore(&pm_qos_lock, flags); + if (pending_update) + update_target(pm_qos_class); +} +EXPORT_SYMBOL_GPL(pm_qos_remove_requirement); + +/** + * pm_qos_add_notifier - sets notification entry for changes to target value + * @pm_qos_class: identifies which qos target changes should be notified. + * @notifier: notifier block managed by caller. + * + * will register the notifier into a notification chain that gets called + * uppon changes to the pm_qos_class target value. + */ + int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) +{ + int retval; + + retval = blocking_notifier_chain_register( + pm_qos_array[pm_qos_class]->notifiers, notifier); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_qos_add_notifier); + +/** + * pm_qos_remove_notifier - deletes notification entry from chain. + * @pm_qos_class: identifies which qos target changes are notified. + * @notifier: notifier block to be removed. + * + * will remove the notifier from the notification chain that gets called + * uppon changes to the pm_qos_class target value. + */ +int pm_qos_remove_notifier(int pm_qos_class, struct notifier_block *notifier) +{ + int retval; + + retval = blocking_notifier_chain_unregister( + pm_qos_array[pm_qos_class]->notifiers, notifier); + + return retval; +} +EXPORT_SYMBOL_GPL(pm_qos_remove_notifier); + +#define PID_NAME_LEN sizeof("process_1234567890") +static char name[PID_NAME_LEN]; + +static int pm_qos_power_open(struct inode *inode, struct file *filp) +{ + int ret; + long pm_qos_class; + + pm_qos_class = find_pm_qos_object_by_minor(iminor(inode)); + if (pm_qos_class >= 0) { + filp->private_data = (void *)pm_qos_class; + sprintf(name, "process_%d", current->pid); + ret = pm_qos_add_requirement(pm_qos_class, name, + PM_QOS_DEFAULT_VALUE); + if (ret >= 0) + return 0; + } + + return -EPERM; +} + +static int pm_qos_power_release(struct inode *inode, struct file *filp) +{ + int pm_qos_class; + + pm_qos_class = (long)filp->private_data; + sprintf(name, "process_%d", current->pid); + pm_qos_remove_requirement(pm_qos_class, name); + + return 0; +} + +static ssize_t pm_qos_power_write(struct file *filp, const char __user *buf, + size_t count, loff_t *f_pos) +{ + s32 value; + int pm_qos_class; + + pm_qos_class = (long)filp->private_data; + if (count != sizeof(s32)) + return -EINVAL; + if (copy_from_user(&value, buf, sizeof(s32))) + return -EFAULT; + sprintf(name, "process_%d", current->pid); + pm_qos_update_requirement(pm_qos_class, name, value); + + return sizeof(s32); +} + + +static int __init pm_qos_power_init(void) +{ + int ret = 0; + + ret = register_pm_qos_misc(&cpu_dma_pm_qos); + if (ret < 0) { + printk(KERN_ERR "pm_qos_param: cpu_dma_latency setup failed\n"); + return ret; + } + ret = register_pm_qos_misc(&network_lat_pm_qos); + if (ret < 0) { + printk(KERN_ERR "pm_qos_param: network_latency setup failed\n"); + return ret; + } + ret = register_pm_qos_misc(&network_throughput_pm_qos); + if (ret < 0) + printk(KERN_ERR + "pm_qos_param: network_throughput setup failed\n"); + + return ret; +} + +late_initcall(pm_qos_power_init); diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index 68c96376e84..0b7c82ac467 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -967,6 +967,7 @@ static void check_thread_timers(struct task_struct *tsk, { int maxfire; struct list_head *timers = tsk->cpu_timers; + struct signal_struct *const sig = tsk->signal; maxfire = 20; tsk->it_prof_expires = cputime_zero; @@ -1011,6 +1012,35 @@ static void check_thread_timers(struct task_struct *tsk, t->firing = 1; list_move_tail(&t->entry, firing); } + + /* + * Check for the special case thread timers. + */ + if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) { + unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max; + unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur; + + if (hard != RLIM_INFINITY && + tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { + /* + * At the hard limit, we just die. + * No need to calculate anything else now. + */ + __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); + return; + } + if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) { + /* + * At the soft limit, send a SIGXCPU every second. + */ + if (sig->rlim[RLIMIT_RTTIME].rlim_cur + < sig->rlim[RLIMIT_RTTIME].rlim_max) { + sig->rlim[RLIMIT_RTTIME].rlim_cur += + USEC_PER_SEC; + } + __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); + } + } } /* diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index 35b4bbfc78f..122d5c787fe 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -256,8 +256,9 @@ static void schedule_next_timer(struct k_itimer *timr) if (timr->it.real.interval.tv64 == 0) return; - timr->it_overrun += hrtimer_forward(timer, timer->base->get_time(), - timr->it.real.interval); + timr->it_overrun += (unsigned int) hrtimer_forward(timer, + timer->base->get_time(), + timr->it.real.interval); timr->it_overrun_last = timr->it_overrun; timr->it_overrun = -1; @@ -386,7 +387,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer) now = ktime_add(now, kj); } #endif - timr->it_overrun += + timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, timr->it.real.interval); ret = HRTIMER_RESTART; @@ -493,7 +494,7 @@ sys_timer_create(const clockid_t which_clock, goto retry; else if (error) { /* - * Wierd looking, but we return EAGAIN if the IDR is + * Weird looking, but we return EAGAIN if the IDR is * full (proper POSIX return value for this) */ error = -EAGAIN; @@ -662,7 +663,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting) */ if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING || (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) - timr->it_overrun += hrtimer_forward(timer, now, iv); + timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv); remaining = ktime_sub(timer->expires, now); /* Return 0 only, when the timer is expired and not pending */ diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 8e186c67814..79833170bb9 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -44,17 +44,38 @@ config PM_VERBOSE ---help--- This option enables verbose messages from the Power Management code. +config CAN_PM_TRACE + def_bool y + depends on PM_DEBUG && PM_SLEEP && EXPERIMENTAL + config PM_TRACE + bool + help + This enables code to save the last PM event point across + reboot. The architecture needs to support this, x86 for + example does by saving things in the RTC, see below. + + The architecture specific code must provide the extern + functions from <linux/resume-trace.h> as well as the + <asm/resume-trace.h> header with a TRACE_RESUME() macro. + + The way the information is presented is architecture- + dependent, x86 will print the information during a + late_initcall. + +config PM_TRACE_RTC bool "Suspend/resume event tracing" - depends on PM_DEBUG && X86 && PM_SLEEP && EXPERIMENTAL + depends on CAN_PM_TRACE + depends on X86 + select PM_TRACE default n ---help--- This enables some cheesy code to save the last PM event point in the RTC across reboots, so that you can debug a machine that just hangs during suspend (or more commonly, during resume). - To use this debugging feature you should attempt to suspend the machine, - then reboot it, then run + To use this debugging feature you should attempt to suspend the + machine, reboot it and then run dmesg -s 1000000 | grep 'hash matches' @@ -63,7 +84,8 @@ config PM_TRACE config PM_SLEEP_SMP bool - depends on SUSPEND_SMP_POSSIBLE || HIBERNATION_SMP_POSSIBLE + depends on SMP + depends on ARCH_SUSPEND_POSSIBLE || ARCH_HIBERNATION_POSSIBLE depends on PM_SLEEP select HOTPLUG_CPU default y @@ -73,52 +95,38 @@ config PM_SLEEP depends on SUSPEND || HIBERNATION default y -config SUSPEND_UP_POSSIBLE - bool - depends on (X86 && !X86_VOYAGER) || PPC || ARM || BLACKFIN || MIPS \ - || SUPERH || FRV - depends on !SMP - default y - -config SUSPEND_SMP_POSSIBLE - bool - depends on (X86 && !X86_VOYAGER) \ - || (PPC && (PPC_PSERIES || PPC_PMAC)) || ARM - depends on SMP - default y - config SUSPEND bool "Suspend to RAM and standby" - depends on PM - depends on SUSPEND_UP_POSSIBLE || SUSPEND_SMP_POSSIBLE + depends on PM && ARCH_SUSPEND_POSSIBLE default y ---help--- Allow the system to enter sleep states in which main memory is powered and thus its contents are preserved, such as the - suspend-to-RAM state (i.e. the ACPI S3 state). + suspend-to-RAM state (e.g. the ACPI S3 state). -config HIBERNATION_UP_POSSIBLE - bool - depends on X86 || PPC64_SWSUSP || PPC32 - depends on !SMP +config SUSPEND_FREEZER + bool "Enable freezer for suspend to RAM/standby" \ + if ARCH_WANTS_FREEZER_CONTROL || BROKEN + depends on SUSPEND default y + help + This allows you to turn off the freezer for suspend. If this is + done, no tasks are frozen for suspend to RAM/standby. -config HIBERNATION_SMP_POSSIBLE - bool - depends on (X86 && !X86_VOYAGER) || PPC64_SWSUSP - depends on SMP - default y + Turning OFF this setting is NOT recommended! If in doubt, say Y. config HIBERNATION bool "Hibernation (aka 'suspend to disk')" - depends on PM && SWAP - depends on HIBERNATION_UP_POSSIBLE || HIBERNATION_SMP_POSSIBLE + depends on PM && SWAP && ARCH_HIBERNATION_POSSIBLE ---help--- Enable the suspend to disk (STD) functionality, which is usually called "hibernation" in user interfaces. STD checkpoints the system and powers it off; and restores that checkpoint on reboot. - You can suspend your machine with 'echo disk > /sys/power/state'. + You can suspend your machine with 'echo disk > /sys/power/state' + after placing resume=/dev/swappartition on the kernel command line + in your bootloader's configuration file. + Alternatively, you can use the additional userland tools available from <http://suspend.sf.net>. diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 05b64790fe8..859a8e59773 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -26,7 +26,7 @@ static int noresume = 0; -char resume_file[256] = CONFIG_PM_STD_PARTITION; +static char resume_file[256] = CONFIG_PM_STD_PARTITION; dev_t swsusp_resume_device; sector_t swsusp_resume_block; @@ -54,8 +54,8 @@ static struct platform_hibernation_ops *hibernation_ops; void hibernation_set_ops(struct platform_hibernation_ops *ops) { - if (ops && !(ops->start && ops->pre_snapshot && ops->finish - && ops->prepare && ops->enter && ops->pre_restore + if (ops && !(ops->begin && ops->end && ops->pre_snapshot + && ops->prepare && ops->finish && ops->enter && ops->pre_restore && ops->restore_cleanup)) { WARN_ON(1); return; @@ -70,15 +70,55 @@ void hibernation_set_ops(struct platform_hibernation_ops *ops) mutex_unlock(&pm_mutex); } +#ifdef CONFIG_PM_DEBUG +static void hibernation_debug_sleep(void) +{ + printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n"); + mdelay(5000); +} + +static int hibernation_testmode(int mode) +{ + if (hibernation_mode == mode) { + hibernation_debug_sleep(); + return 1; + } + return 0; +} + +static int hibernation_test(int level) +{ + if (pm_test_level == level) { + hibernation_debug_sleep(); + return 1; + } + return 0; +} +#else /* !CONFIG_PM_DEBUG */ +static int hibernation_testmode(int mode) { return 0; } +static int hibernation_test(int level) { return 0; } +#endif /* !CONFIG_PM_DEBUG */ + /** - * platform_start - tell the platform driver that we're starting + * platform_begin - tell the platform driver that we're starting * hibernation */ -static int platform_start(int platform_mode) +static int platform_begin(int platform_mode) { return (platform_mode && hibernation_ops) ? - hibernation_ops->start() : 0; + hibernation_ops->begin() : 0; +} + +/** + * platform_end - tell the platform driver that we've entered the + * working state + */ + +static void platform_end(int platform_mode) +{ + if (platform_mode && hibernation_ops) + hibernation_ops->end(); } /** @@ -145,7 +185,7 @@ static void platform_restore_cleanup(int platform_mode) * reappears in this routine after a restore. */ -int create_image(int platform_mode) +static int create_image(int platform_mode) { int error; @@ -162,19 +202,25 @@ int create_image(int platform_mode) */ error = device_power_down(PMSG_FREEZE); if (error) { - printk(KERN_ERR "Some devices failed to power down, " - KERN_ERR "aborting suspend\n"); + printk(KERN_ERR "PM: Some devices failed to power down, " + "aborting hibernation\n"); goto Enable_irqs; } + if (hibernation_test(TEST_CORE)) + goto Power_up; + + in_suspend = 1; save_processor_state(); error = swsusp_arch_suspend(); if (error) - printk(KERN_ERR "Error %d while creating the image\n", error); + printk(KERN_ERR "PM: Error %d creating hibernation image\n", + error); /* Restore control flow magically appears here */ restore_processor_state(); if (!in_suspend) platform_leave(platform_mode); + Power_up: /* NOTE: device_power_up() is just a resume() for devices * that suspended with irqs off ... no overall powerup. */ @@ -202,36 +248,90 @@ int hibernation_snapshot(int platform_mode) if (error) return error; - error = platform_start(platform_mode); + error = platform_begin(platform_mode); if (error) - return error; + goto Close; suspend_console(); error = device_suspend(PMSG_FREEZE); if (error) goto Resume_console; - error = platform_pre_snapshot(platform_mode); - if (error) + if (hibernation_test(TEST_DEVICES)) goto Resume_devices; + error = platform_pre_snapshot(platform_mode); + if (error || hibernation_test(TEST_PLATFORM)) + goto Finish; + error = disable_nonboot_cpus(); if (!error) { - if (hibernation_mode != HIBERNATION_TEST) { - in_suspend = 1; - error = create_image(platform_mode); - /* Control returns here after successful restore */ - } else { - printk("swsusp debug: Waiting for 5 seconds.\n"); - mdelay(5000); - } + if (hibernation_test(TEST_CPUS)) + goto Enable_cpus; + + if (hibernation_testmode(HIBERNATION_TEST)) + goto Enable_cpus; + + error = create_image(platform_mode); + /* Control returns here after successful restore */ } + Enable_cpus: enable_nonboot_cpus(); - Resume_devices: + Finish: platform_finish(platform_mode); + Resume_devices: device_resume(); Resume_console: resume_console(); + Close: + platform_end(platform_mode); + return error; +} + +/** + * resume_target_kernel - prepare devices that need to be suspended with + * interrupts off, restore the contents of highmem that have not been + * restored yet from the image and run the low level code that will restore + * the remaining contents of memory and switch to the just restored target + * kernel. + */ + +static int resume_target_kernel(void) +{ + int error; + + local_irq_disable(); + error = device_power_down(PMSG_PRETHAW); + if (error) { + printk(KERN_ERR "PM: Some devices failed to power down, " + "aborting resume\n"); + goto Enable_irqs; + } + /* We'll ignore saved state, but this gets preempt count (etc) right */ + save_processor_state(); + error = restore_highmem(); + if (!error) { + error = swsusp_arch_resume(); + /* + * The code below is only ever reached in case of a failure. + * Otherwise execution continues at place where + * swsusp_arch_suspend() was called + */ + BUG_ON(!error); + /* This call to restore_highmem() undos the previous one */ + restore_highmem(); + } + /* + * The only reason why swsusp_arch_resume() can fail is memory being + * very tight, so we have to free it as soon as we can to avoid + * subsequent failures + */ + swsusp_free(); + restore_processor_state(); + touch_softlockup_watchdog(); + device_power_up(); + Enable_irqs: + local_irq_enable(); return error; } @@ -258,7 +358,7 @@ int hibernation_restore(int platform_mode) if (!error) { error = disable_nonboot_cpus(); if (!error) - error = swsusp_resume(); + error = resume_target_kernel(); enable_nonboot_cpus(); } platform_restore_cleanup(platform_mode); @@ -286,9 +386,9 @@ int hibernation_platform_enter(void) * hibernation_ops->finish() before saving the image, so we should let * the firmware know that we're going to enter the sleep state after all */ - error = hibernation_ops->start(); + error = hibernation_ops->begin(); if (error) - return error; + goto Close; suspend_console(); error = device_suspend(PMSG_SUSPEND); @@ -322,6 +422,8 @@ int hibernation_platform_enter(void) device_resume(); Resume_console: resume_console(); + Close: + hibernation_ops->end(); return error; } @@ -352,24 +454,17 @@ static void power_down(void) * Valid image is on the disk, if we continue we risk serious data * corruption after resume. */ - printk(KERN_CRIT "Please power me down manually\n"); + printk(KERN_CRIT "PM: Please power down manually\n"); while(1); } -static void unprepare_processes(void) -{ - thaw_processes(); - pm_restore_console(); -} - static int prepare_processes(void) { int error = 0; - pm_prepare_console(); if (freeze_processes()) { error = -EBUSY; - unprepare_processes(); + thaw_processes(); } return error; } @@ -389,6 +484,7 @@ int hibernate(void) goto Unlock; } + pm_prepare_console(); error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE); if (error) goto Exit; @@ -398,7 +494,7 @@ int hibernate(void) if (error) goto Exit; - printk("Syncing filesystems ... "); + printk(KERN_INFO "PM: Syncing filesystems ... "); sys_sync(); printk("done.\n"); @@ -406,11 +502,12 @@ int hibernate(void) if (error) goto Finish; - if (hibernation_mode == HIBERNATION_TESTPROC) { - printk("swsusp debug: Waiting for 5 seconds.\n"); - mdelay(5000); + if (hibernation_test(TEST_FREEZER)) goto Thaw; - } + + if (hibernation_testmode(HIBERNATION_TESTPROC)) + goto Thaw; + error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM); if (in_suspend && !error) { unsigned int flags = 0; @@ -427,11 +524,12 @@ int hibernate(void) swsusp_free(); } Thaw: - unprepare_processes(); + thaw_processes(); Finish: free_basic_memory_bitmaps(); Exit: pm_notifier_call_chain(PM_POST_HIBERNATION); + pm_restore_console(); atomic_inc(&snapshot_device_available); Unlock: mutex_unlock(&pm_mutex); @@ -473,22 +571,23 @@ static int software_resume(void) return -ENOENT; } swsusp_resume_device = name_to_dev_t(resume_file); - pr_debug("swsusp: Resume From Partition %s\n", resume_file); + pr_debug("PM: Resume from partition %s\n", resume_file); } else { - pr_debug("swsusp: Resume From Partition %d:%d\n", - MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); + pr_debug("PM: Resume from partition %d:%d\n", + MAJOR(swsusp_resume_device), + MINOR(swsusp_resume_device)); } if (noresume) { /** - * FIXME: If noresume is specified, we need to find the partition - * and reset it back to normal swap space. + * FIXME: If noresume is specified, we need to find the + * partition and reset it back to normal swap space. */ mutex_unlock(&pm_mutex); return 0; } - pr_debug("PM: Checking swsusp image.\n"); + pr_debug("PM: Checking hibernation image.\n"); error = swsusp_check(); if (error) goto Unlock; @@ -499,6 +598,11 @@ static int software_resume(void) goto Unlock; } + pm_prepare_console(); + error = pm_notifier_call_chain(PM_RESTORE_PREPARE); + if (error) + goto Finish; + error = create_basic_memory_bitmaps(); if (error) goto Finish; @@ -510,7 +614,7 @@ static int software_resume(void) goto Done; } - pr_debug("PM: Reading swsusp image.\n"); + pr_debug("PM: Reading hibernation image.\n"); error = swsusp_read(&flags); if (!error) @@ -518,10 +622,12 @@ static int software_resume(void) printk(KERN_ERR "PM: Restore failed, recovering.\n"); swsusp_free(); - unprepare_processes(); + thaw_processes(); Done: free_basic_memory_bitmaps(); Finish: + pm_notifier_call_chain(PM_POST_RESTORE); + pm_restore_console(); atomic_inc(&snapshot_device_available); /* For success case, the suspend path will release the lock */ Unlock: @@ -567,7 +673,8 @@ static const char * const hibernation_modes[] = { * supports it (as determined by having hibernation_ops). */ -static ssize_t disk_show(struct kset *kset, char *buf) +static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) { int i; char *start = buf; @@ -597,7 +704,8 @@ static ssize_t disk_show(struct kset *kset, char *buf) } -static ssize_t disk_store(struct kset *kset, const char *buf, size_t n) +static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) { int error = 0; int i; @@ -634,7 +742,7 @@ static ssize_t disk_store(struct kset *kset, const char *buf, size_t n) error = -EINVAL; if (!error) - pr_debug("PM: suspend-to-disk mode set to '%s'\n", + pr_debug("PM: Hibernation mode set to '%s'\n", hibernation_modes[mode]); mutex_unlock(&pm_mutex); return error ? error : n; @@ -642,13 +750,15 @@ static ssize_t disk_store(struct kset *kset, const char *buf, size_t n) power_attr(disk); -static ssize_t resume_show(struct kset *kset, char *buf) +static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) { return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); } -static ssize_t resume_store(struct kset *kset, const char *buf, size_t n) +static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) { unsigned int maj, min; dev_t res; @@ -664,7 +774,7 @@ static ssize_t resume_store(struct kset *kset, const char *buf, size_t n) mutex_lock(&pm_mutex); swsusp_resume_device = res; mutex_unlock(&pm_mutex); - printk("Attempting manual resume\n"); + printk(KERN_INFO "PM: Starting manual resume from disk\n"); noresume = 0; software_resume(); ret = n; @@ -674,12 +784,14 @@ static ssize_t resume_store(struct kset *kset, const char *buf, size_t n) power_attr(resume); -static ssize_t image_size_show(struct kset *kset, char *buf) +static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) { return sprintf(buf, "%lu\n", image_size); } -static ssize_t image_size_store(struct kset *kset, const char *buf, size_t n) +static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) { unsigned long size; @@ -708,7 +820,7 @@ static struct attribute_group attr_group = { static int __init pm_disk_init(void) { - return sysfs_create_group(&power_subsys.kobj, &attr_group); + return sysfs_create_group(power_kobj, &attr_group); } core_initcall(pm_disk_init); diff --git a/kernel/power/main.c b/kernel/power/main.c index 3cdf95b1dc9..6a6d5eb3524 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -24,10 +24,112 @@ #include "power.h" -BLOCKING_NOTIFIER_HEAD(pm_chain_head); - DEFINE_MUTEX(pm_mutex); +unsigned int pm_flags; +EXPORT_SYMBOL(pm_flags); + +#ifdef CONFIG_PM_SLEEP + +/* Routines for PM-transition notifications */ + +static BLOCKING_NOTIFIER_HEAD(pm_chain_head); + +int register_pm_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_register(&pm_chain_head, nb); +} +EXPORT_SYMBOL_GPL(register_pm_notifier); + +int unregister_pm_notifier(struct notifier_block *nb) +{ + return blocking_notifier_chain_unregister(&pm_chain_head, nb); +} +EXPORT_SYMBOL_GPL(unregister_pm_notifier); + +int pm_notifier_call_chain(unsigned long val) +{ + return (blocking_notifier_call_chain(&pm_chain_head, val, NULL) + == NOTIFY_BAD) ? -EINVAL : 0; +} + +#ifdef CONFIG_PM_DEBUG +int pm_test_level = TEST_NONE; + +static int suspend_test(int level) +{ + if (pm_test_level == level) { + printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n"); + mdelay(5000); + return 1; + } + return 0; +} + +static const char * const pm_tests[__TEST_AFTER_LAST] = { + [TEST_NONE] = "none", + [TEST_CORE] = "core", + [TEST_CPUS] = "processors", + [TEST_PLATFORM] = "platform", + [TEST_DEVICES] = "devices", + [TEST_FREEZER] = "freezer", +}; + +static ssize_t pm_test_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + char *s = buf; + int level; + + for (level = TEST_FIRST; level <= TEST_MAX; level++) + if (pm_tests[level]) { + if (level == pm_test_level) + s += sprintf(s, "[%s] ", pm_tests[level]); + else + s += sprintf(s, "%s ", pm_tests[level]); + } + + if (s != buf) + /* convert the last space to a newline */ + *(s-1) = '\n'; + + return (s - buf); +} + +static ssize_t pm_test_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) +{ + const char * const *s; + int level; + char *p; + int len; + int error = -EINVAL; + + p = memchr(buf, '\n', n); + len = p ? p - buf : n; + + mutex_lock(&pm_mutex); + + level = TEST_FIRST; + for (s = &pm_tests[level]; level <= TEST_MAX; s++, level++) + if (*s && len == strlen(*s) && !strncmp(buf, *s, len)) { + pm_test_level = level; + error = 0; + break; + } + + mutex_unlock(&pm_mutex); + + return error ? error : n; +} + +power_attr(pm_test); +#else /* !CONFIG_PM_DEBUG */ +static inline int suspend_test(int level) { return 0; } +#endif /* !CONFIG_PM_DEBUG */ + +#endif /* CONFIG_PM_SLEEP */ + #ifdef CONFIG_SUSPEND /* This is just an arbitrary number */ @@ -73,13 +175,13 @@ static int suspend_prepare(void) if (!suspend_ops || !suspend_ops->enter) return -EPERM; + pm_prepare_console(); + error = pm_notifier_call_chain(PM_SUSPEND_PREPARE); if (error) goto Finish; - pm_prepare_console(); - - if (freeze_processes()) { + if (suspend_freeze_processes()) { error = -EAGAIN; goto Thaw; } @@ -97,10 +199,10 @@ static int suspend_prepare(void) return 0; Thaw: - thaw_processes(); - pm_restore_console(); + suspend_thaw_processes(); Finish: pm_notifier_call_chain(PM_POST_SUSPEND); + pm_restore_console(); return error; } @@ -130,10 +232,13 @@ static int suspend_enter(suspend_state_t state) BUG_ON(!irqs_disabled()); if ((error = device_power_down(PMSG_SUSPEND))) { - printk(KERN_ERR "Some devices failed to power down\n"); + printk(KERN_ERR "PM: Some devices failed to power down\n"); goto Done; } - error = suspend_ops->enter(state); + + if (!suspend_test(TEST_CORE)) + error = suspend_ops->enter(state); + device_power_up(); Done: arch_suspend_enable_irqs(); @@ -142,8 +247,8 @@ static int suspend_enter(suspend_state_t state) } /** - * suspend_devices_and_enter - suspend devices and enter the desired system sleep - * state. + * suspend_devices_and_enter - suspend devices and enter the desired system + * sleep state. * @state: state to enter */ int suspend_devices_and_enter(suspend_state_t state) @@ -153,33 +258,45 @@ int suspend_devices_and_enter(suspend_state_t state) if (!suspend_ops) return -ENOSYS; - if (suspend_ops->set_target) { - error = suspend_ops->set_target(state); + if (suspend_ops->begin) { + error = suspend_ops->begin(state); if (error) - return error; + goto Close; } suspend_console(); error = device_suspend(PMSG_SUSPEND); if (error) { - printk(KERN_ERR "Some devices failed to suspend\n"); + printk(KERN_ERR "PM: Some devices failed to suspend\n"); goto Resume_console; } + + if (suspend_test(TEST_DEVICES)) + goto Resume_devices; + if (suspend_ops->prepare) { error = suspend_ops->prepare(); if (error) goto Resume_devices; } + + if (suspend_test(TEST_PLATFORM)) + goto Finish; + error = disable_nonboot_cpus(); - if (!error) + if (!error && !suspend_test(TEST_CPUS)) suspend_enter(state); enable_nonboot_cpus(); + Finish: if (suspend_ops->finish) suspend_ops->finish(); Resume_devices: device_resume(); Resume_console: resume_console(); + Close: + if (suspend_ops->end) + suspend_ops->end(); return error; } @@ -191,9 +308,9 @@ int suspend_devices_and_enter(suspend_state_t state) */ static void suspend_finish(void) { - thaw_processes(); - pm_restore_console(); + suspend_thaw_processes(); pm_notifier_call_chain(PM_POST_SUSPEND); + pm_restore_console(); } @@ -235,17 +352,22 @@ static int enter_state(suspend_state_t state) if (!mutex_trylock(&pm_mutex)) return -EBUSY; - printk("Syncing filesystems ... "); + printk(KERN_INFO "PM: Syncing filesystems ... "); sys_sync(); printk("done.\n"); pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]); - if ((error = suspend_prepare())) + error = suspend_prepare(); + if (error) goto Unlock; + if (suspend_test(TEST_FREEZER)) + goto Finish; + pr_debug("PM: Entering %s sleep\n", pm_states[state]); error = suspend_devices_and_enter(state); + Finish: pr_debug("PM: Finishing wakeup.\n"); suspend_finish(); Unlock: @@ -273,8 +395,7 @@ EXPORT_SYMBOL(pm_suspend); #endif /* CONFIG_SUSPEND */ -decl_subsys(power,NULL,NULL); - +struct kobject *power_kobj; /** * state - control system power state. @@ -287,7 +408,8 @@ decl_subsys(power,NULL,NULL); * proper enumerated value, and initiates a suspend transition. */ -static ssize_t state_show(struct kset *kset, char *buf) +static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) { char *s = buf; #ifdef CONFIG_SUSPEND @@ -308,7 +430,8 @@ static ssize_t state_show(struct kset *kset, char *buf) return (s - buf); } -static ssize_t state_store(struct kset *kset, const char *buf, size_t n) +static ssize_t state_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) { #ifdef CONFIG_SUSPEND suspend_state_t state = PM_SUSPEND_STANDBY; @@ -345,13 +468,15 @@ power_attr(state); #ifdef CONFIG_PM_TRACE int pm_trace_enabled; -static ssize_t pm_trace_show(struct kset *kset, char *buf) +static ssize_t pm_trace_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) { return sprintf(buf, "%d\n", pm_trace_enabled); } static ssize_t -pm_trace_store(struct kset *kset, const char *buf, size_t n) +pm_trace_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) { int val; @@ -363,18 +488,18 @@ pm_trace_store(struct kset *kset, const char *buf, size_t n) } power_attr(pm_trace); +#endif /* CONFIG_PM_TRACE */ static struct attribute * g[] = { &state_attr.attr, +#ifdef CONFIG_PM_TRACE &pm_trace_attr.attr, +#endif +#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_PM_DEBUG) + &pm_test_attr.attr, +#endif NULL, }; -#else -static struct attribute * g[] = { - &state_attr.attr, - NULL, -}; -#endif /* CONFIG_PM_TRACE */ static struct attribute_group attr_group = { .attrs = g, @@ -383,10 +508,10 @@ static struct attribute_group attr_group = { static int __init pm_init(void) { - int error = subsystem_register(&power_subsys); - if (!error) - error = sysfs_create_group(&power_subsys.kobj,&attr_group); - return error; + power_kobj = kobject_create_and_add("power", NULL); + if (!power_kobj) + return -ENOMEM; + return sysfs_create_group(power_kobj, &attr_group); } core_initcall(pm_init); diff --git a/kernel/power/pm.c b/kernel/power/pm.c index c50d15266c1..60c73fa670d 100644 --- a/kernel/power/pm.c +++ b/kernel/power/pm.c @@ -27,8 +27,6 @@ #include <linux/interrupt.h> #include <linux/mutex.h> -int pm_active; - /* * Locking notes: * pm_devs_lock can be a semaphore providing pm ops are not called @@ -204,6 +202,4 @@ int pm_send_all(pm_request_t rqst, void *data) EXPORT_SYMBOL(pm_register); EXPORT_SYMBOL(pm_send_all); -EXPORT_SYMBOL(pm_active); - diff --git a/kernel/power/power.h b/kernel/power/power.h index 195dc461176..700f44ec840 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -1,5 +1,7 @@ #include <linux/suspend.h> +#include <linux/suspend_ioctls.h> #include <linux/utsname.h> +#include <linux/freezer.h> struct swsusp_info { struct new_utsname uts; @@ -54,7 +56,7 @@ extern int pfn_is_nosave(unsigned long); extern struct mutex pm_mutex; #define power_attr(_name) \ -static struct subsys_attribute _name##_attr = { \ +static struct kobj_attribute _name##_attr = { \ .attr = { \ .name = __stringify(_name), \ .mode = 0644, \ @@ -63,8 +65,6 @@ static struct subsys_attribute _name##_attr = { \ .store = _name##_store, \ } -extern struct kset power_subsys; - /* Preferred image size in bytes (default 500 MB) */ extern unsigned long image_size; extern int in_suspend; @@ -130,42 +130,12 @@ struct snapshot_handle { #define data_of(handle) ((handle).buffer + (handle).buf_offset) extern unsigned int snapshot_additional_pages(struct zone *zone); +extern unsigned long snapshot_get_image_size(void); extern int snapshot_read_next(struct snapshot_handle *handle, size_t count); extern int snapshot_write_next(struct snapshot_handle *handle, size_t count); extern void snapshot_write_finalize(struct snapshot_handle *handle); extern int snapshot_image_loaded(struct snapshot_handle *handle); -/* - * This structure is used to pass the values needed for the identification - * of the resume swap area from a user space to the kernel via the - * SNAPSHOT_SET_SWAP_AREA ioctl - */ -struct resume_swap_area { - loff_t offset; - u_int32_t dev; -} __attribute__((packed)); - -#define SNAPSHOT_IOC_MAGIC '3' -#define SNAPSHOT_FREEZE _IO(SNAPSHOT_IOC_MAGIC, 1) -#define SNAPSHOT_UNFREEZE _IO(SNAPSHOT_IOC_MAGIC, 2) -#define SNAPSHOT_ATOMIC_SNAPSHOT _IOW(SNAPSHOT_IOC_MAGIC, 3, void *) -#define SNAPSHOT_ATOMIC_RESTORE _IO(SNAPSHOT_IOC_MAGIC, 4) -#define SNAPSHOT_FREE _IO(SNAPSHOT_IOC_MAGIC, 5) -#define SNAPSHOT_SET_IMAGE_SIZE _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long) -#define SNAPSHOT_AVAIL_SWAP _IOR(SNAPSHOT_IOC_MAGIC, 7, void *) -#define SNAPSHOT_GET_SWAP_PAGE _IOR(SNAPSHOT_IOC_MAGIC, 8, void *) -#define SNAPSHOT_FREE_SWAP_PAGES _IO(SNAPSHOT_IOC_MAGIC, 9) -#define SNAPSHOT_SET_SWAP_FILE _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int) -#define SNAPSHOT_S2RAM _IO(SNAPSHOT_IOC_MAGIC, 11) -#define SNAPSHOT_PMOPS _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int) -#define SNAPSHOT_SET_SWAP_AREA _IOW(SNAPSHOT_IOC_MAGIC, 13, \ - struct resume_swap_area) -#define SNAPSHOT_IOC_MAXNR 13 - -#define PMOPS_PREPARE 1 -#define PMOPS_ENTER 2 -#define PMOPS_FINISH 3 - /* If unset, the snapshot device cannot be open. */ extern atomic_t snapshot_device_available; @@ -183,7 +153,6 @@ extern int swsusp_swap_in_use(void); extern int swsusp_check(void); extern int swsusp_shrink_memory(void); extern void swsusp_free(void); -extern int swsusp_resume(void); extern int swsusp_read(unsigned int *flags_p); extern int swsusp_write(unsigned int flags); extern void swsusp_close(void); @@ -203,11 +172,56 @@ static inline int suspend_devices_and_enter(suspend_state_t state) } #endif /* !CONFIG_SUSPEND */ -/* kernel/power/common.c */ -extern struct blocking_notifier_head pm_chain_head; +#ifdef CONFIG_PM_SLEEP +/* kernel/power/main.c */ +extern int pm_notifier_call_chain(unsigned long val); +#endif + +#ifdef CONFIG_HIGHMEM +unsigned int count_highmem_pages(void); +int restore_highmem(void); +#else +static inline unsigned int count_highmem_pages(void) { return 0; } +static inline int restore_highmem(void) { return 0; } +#endif + +/* + * Suspend test levels + */ +enum { + /* keep first */ + TEST_NONE, + TEST_CORE, + TEST_CPUS, + TEST_PLATFORM, + TEST_DEVICES, + TEST_FREEZER, + /* keep last */ + __TEST_AFTER_LAST +}; -static inline int pm_notifier_call_chain(unsigned long val) +#define TEST_FIRST TEST_NONE +#define TEST_MAX (__TEST_AFTER_LAST - 1) + +extern int pm_test_level; + +#ifdef CONFIG_SUSPEND_FREEZER +static inline int suspend_freeze_processes(void) +{ + return freeze_processes(); +} + +static inline void suspend_thaw_processes(void) { - return (blocking_notifier_call_chain(&pm_chain_head, val, NULL) - == NOTIFY_BAD) ? -EINVAL : 0; + thaw_processes(); } +#else +static inline int suspend_freeze_processes(void) +{ + return 0; +} + +static inline void suspend_thaw_processes(void) +{ +} +#endif diff --git a/kernel/power/process.c b/kernel/power/process.c index 6533923e711..7c2118f9597 100644 --- a/kernel/power/process.c +++ b/kernel/power/process.c @@ -86,9 +86,9 @@ static void fake_signal_wake_up(struct task_struct *p, int resume) static void send_fake_signal(struct task_struct *p) { - if (p->state == TASK_STOPPED) + if (task_is_stopped(p)) force_sig_specific(SIGSTOP, p); - fake_signal_wake_up(p, p->state == TASK_STOPPED); + fake_signal_wake_up(p, task_is_stopped(p)); } static int has_mm(struct task_struct *p) @@ -182,7 +182,7 @@ static int try_to_freeze_tasks(int freeze_user_space) if (frozen(p) || !freezeable(p)) continue; - if (p->state == TASK_TRACED && frozen(p->parent)) { + if (task_is_traced(p) && frozen(p->parent)) { cancel_freezing(p); continue; } diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 78039b477d2..95250d7c8d9 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -635,7 +635,7 @@ __register_nosave_region(unsigned long start_pfn, unsigned long end_pfn, region->end_pfn = end_pfn; list_add_tail(®ion->list, &nosave_regions); Report: - printk("swsusp: Registered nosave memory region: %016lx - %016lx\n", + printk(KERN_INFO "PM: Registered nosave memory: %016lx - %016lx\n", start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT); } @@ -704,7 +704,7 @@ static void mark_nosave_pages(struct memory_bitmap *bm) list_for_each_entry(region, &nosave_regions, list) { unsigned long pfn; - printk("swsusp: Marking nosave pages: %016lx - %016lx\n", + pr_debug("PM: Marking nosave pages: %016lx - %016lx\n", region->start_pfn << PAGE_SHIFT, region->end_pfn << PAGE_SHIFT); @@ -749,7 +749,7 @@ int create_basic_memory_bitmaps(void) free_pages_map = bm2; mark_nosave_pages(forbidden_pages_map); - printk("swsusp: Basic memory bitmaps created\n"); + pr_debug("PM: Basic memory bitmaps created\n"); return 0; @@ -784,7 +784,7 @@ void free_basic_memory_bitmaps(void) memory_bm_free(bm2, PG_UNSAFE_CLEAR); kfree(bm2); - printk("swsusp: Basic memory bitmaps freed\n"); + pr_debug("PM: Basic memory bitmaps freed\n"); } /** @@ -872,7 +872,6 @@ unsigned int count_highmem_pages(void) } #else static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; } -static inline unsigned int count_highmem_pages(void) { return 0; } #endif /* CONFIG_HIGHMEM */ /** @@ -1089,7 +1088,7 @@ static int enough_free_mem(unsigned int nr_pages, unsigned int nr_highmem) } nr_pages += count_pages_for_highmem(nr_highmem); - pr_debug("swsusp: Normal pages needed: %u + %u + %u, available pages: %u\n", + pr_debug("PM: Normal pages needed: %u + %u + %u, available pages: %u\n", nr_pages, PAGES_FOR_IO, meta, free); return free > nr_pages + PAGES_FOR_IO + meta; @@ -1202,27 +1201,27 @@ asmlinkage int swsusp_save(void) { unsigned int nr_pages, nr_highmem; - printk("swsusp: critical section: \n"); + printk(KERN_INFO "PM: Creating hibernation image: \n"); - drain_local_pages(); + drain_local_pages(NULL); nr_pages = count_data_pages(); nr_highmem = count_highmem_pages(); - printk("swsusp: Need to copy %u pages\n", nr_pages + nr_highmem); + printk(KERN_INFO "PM: Need to copy %u pages\n", nr_pages + nr_highmem); if (!enough_free_mem(nr_pages, nr_highmem)) { - printk(KERN_ERR "swsusp: Not enough free memory\n"); + printk(KERN_ERR "PM: Not enough free memory\n"); return -ENOMEM; } if (swsusp_alloc(&orig_bm, ©_bm, nr_pages, nr_highmem)) { - printk(KERN_ERR "swsusp: Memory allocation failed\n"); + printk(KERN_ERR "PM: Memory allocation failed\n"); return -ENOMEM; } /* During allocating of suspend pagedir, new cold pages may appear. * Kill them. */ - drain_local_pages(); + drain_local_pages(NULL); copy_data_pages(©_bm, &orig_bm); /* @@ -1235,7 +1234,8 @@ asmlinkage int swsusp_save(void) nr_copy_pages = nr_pages; nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); - printk("swsusp: critical section: done (%d pages copied)\n", nr_pages); + printk(KERN_INFO "PM: Hibernation image created (%d pages copied)\n", + nr_pages); return 0; } @@ -1264,12 +1264,17 @@ static char *check_image_kernel(struct swsusp_info *info) } #endif /* CONFIG_ARCH_HIBERNATION_HEADER */ +unsigned long snapshot_get_image_size(void) +{ + return nr_copy_pages + nr_meta_pages + 1; +} + static int init_header(struct swsusp_info *info) { memset(info, 0, sizeof(struct swsusp_info)); info->num_physpages = num_physpages; info->image_pages = nr_copy_pages; - info->pages = nr_copy_pages + nr_meta_pages + 1; + info->pages = snapshot_get_image_size(); info->size = info->pages; info->size <<= PAGE_SHIFT; return init_header_complete(info); @@ -1429,7 +1434,7 @@ static int check_header(struct swsusp_info *info) if (!reason && info->num_physpages != num_physpages) reason = "memory size"; if (reason) { - printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason); + printk(KERN_ERR "PM: Image mismatch: %s\n", reason); return -EPERM; } return 0; diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 917aba10057..a0abf9a463f 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -28,8 +28,6 @@ #include "power.h" -extern char resume_file[]; - #define SWSUSP_SIG "S1SUSPEND" struct swsusp_header { @@ -73,7 +71,8 @@ static int submit(int rw, pgoff_t page_off, struct page *page, bio->bi_end_io = end_swap_bio_read; if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { - printk("swsusp: ERROR: adding page to bio at %ld\n", page_off); + printk(KERN_ERR "PM: Adding page to bio failed at %ld\n", + page_off); bio_put(bio); return -EFAULT; } @@ -153,7 +152,7 @@ static int mark_swapfiles(sector_t start, unsigned int flags) error = bio_write_page(swsusp_resume_block, swsusp_header, NULL); } else { - printk(KERN_ERR "swsusp: Swap header not found!\n"); + printk(KERN_ERR "PM: Swap header not found!\n"); error = -ENODEV; } return error; @@ -325,7 +324,8 @@ static int save_image(struct swap_map_handle *handle, struct timeval start; struct timeval stop; - printk("Saving image data pages (%u pages) ... ", nr_to_write); + printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ", + nr_to_write); m = nr_to_write / 100; if (!m) m = 1; @@ -365,7 +365,7 @@ static int enough_swap(unsigned int nr_pages) { unsigned int free_swap = count_swap_pages(root_swap, 1); - pr_debug("swsusp: free swap pages: %u\n", free_swap); + pr_debug("PM: Free swap pages: %u\n", free_swap); return free_swap > nr_pages + PAGES_FOR_IO; } @@ -388,7 +388,7 @@ int swsusp_write(unsigned int flags) error = swsusp_swap_check(); if (error) { - printk(KERN_ERR "swsusp: Cannot find swap device, try " + printk(KERN_ERR "PM: Cannot find swap device, try " "swapon -a.\n"); return error; } @@ -402,7 +402,7 @@ int swsusp_write(unsigned int flags) } header = (struct swsusp_info *)data_of(snapshot); if (!enough_swap(header->pages)) { - printk(KERN_ERR "swsusp: Not enough free swap\n"); + printk(KERN_ERR "PM: Not enough free swap\n"); error = -ENOSPC; goto out; } @@ -417,7 +417,7 @@ int swsusp_write(unsigned int flags) if (!error) { flush_swap_writer(&handle); - printk("S"); + printk(KERN_INFO "PM: S"); error = mark_swapfiles(start, flags); printk("|\n"); } @@ -507,7 +507,8 @@ static int load_image(struct swap_map_handle *handle, int err2; unsigned nr_pages; - printk("Loading image data pages (%u pages) ... ", nr_to_read); + printk(KERN_INFO "PM: Loading image data pages (%u pages) ... ", + nr_to_read); m = nr_to_read / 100; if (!m) m = 1; @@ -558,7 +559,7 @@ int swsusp_read(unsigned int *flags_p) *flags_p = swsusp_header->flags; if (IS_ERR(resume_bdev)) { - pr_debug("swsusp: block device not initialised\n"); + pr_debug("PM: Image device not initialised\n"); return PTR_ERR(resume_bdev); } @@ -577,9 +578,9 @@ int swsusp_read(unsigned int *flags_p) blkdev_put(resume_bdev); if (!error) - pr_debug("swsusp: Reading resume file was successful\n"); + pr_debug("PM: Image successfully loaded\n"); else - pr_debug("swsusp: Error %d resuming\n", error); + pr_debug("PM: Error %d resuming\n", error); return error; } @@ -611,13 +612,13 @@ int swsusp_check(void) if (error) blkdev_put(resume_bdev); else - pr_debug("swsusp: Signature found, resuming\n"); + pr_debug("PM: Signature found, resuming\n"); } else { error = PTR_ERR(resume_bdev); } if (error) - pr_debug("swsusp: Error %d check for resume file\n", error); + pr_debug("PM: Error %d checking image file\n", error); return error; } @@ -629,7 +630,7 @@ int swsusp_check(void) void swsusp_close(void) { if (IS_ERR(resume_bdev)) { - pr_debug("swsusp: block device not initialised\n"); + pr_debug("PM: Image device not initialised\n"); return; } diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index e1722d3155f..023ff2a31d8 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -64,14 +64,6 @@ unsigned long image_size = 500 * 1024 * 1024; int in_suspend __nosavedata = 0; -#ifdef CONFIG_HIGHMEM -unsigned int count_highmem_pages(void); -int restore_highmem(void); -#else -static inline int restore_highmem(void) { return 0; } -static inline unsigned int count_highmem_pages(void) { return 0; } -#endif - /** * The following functions are used for tracing the allocated * swap pages, so that they can be freed in case of an error. @@ -196,7 +188,8 @@ void swsusp_show_speed(struct timeval *start, struct timeval *stop, centisecs = 1; /* avoid div-by-zero */ k = nr_pages * (PAGE_SIZE / 1024); kps = (k * 100) / centisecs; - printk("%s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n", msg, k, + printk(KERN_INFO "PM: %s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n", + msg, k, centisecs / 100, centisecs % 100, kps / 1000, (kps % 1000) / 10); } @@ -227,7 +220,7 @@ int swsusp_shrink_memory(void) char *p = "-\\|/"; struct timeval start, stop; - printk("Shrinking memory... "); + printk(KERN_INFO "PM: Shrinking memory... "); do_gettimeofday(&start); do { long size, highmem_size; @@ -269,38 +262,3 @@ int swsusp_shrink_memory(void) return 0; } - -int swsusp_resume(void) -{ - int error; - - local_irq_disable(); - /* NOTE: device_power_down() is just a suspend() with irqs off; - * it has no special "power things down" semantics - */ - if (device_power_down(PMSG_PRETHAW)) - printk(KERN_ERR "Some devices failed to power down, very bad\n"); - /* We'll ignore saved state, but this gets preempt count (etc) right */ - save_processor_state(); - error = restore_highmem(); - if (!error) { - error = swsusp_arch_resume(); - /* The code below is only ever reached in case of a failure. - * Otherwise execution continues at place where - * swsusp_arch_suspend() was called - */ - BUG_ON(!error); - /* This call to restore_highmem() undos the previous one */ - restore_highmem(); - } - /* The only reason why swsusp_arch_resume() can fail is memory being - * very tight, so we have to free it as soon as we can to avoid - * subsequent failures - */ - swsusp_free(); - restore_processor_state(); - touch_softlockup_watchdog(); - device_power_up(); - local_irq_enable(); - return error; -} diff --git a/kernel/power/user.c b/kernel/power/user.c index 5bd321bcbb7..f5512cb3aa8 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -28,6 +28,29 @@ #include "power.h" +/* + * NOTE: The SNAPSHOT_SET_SWAP_FILE and SNAPSHOT_PMOPS ioctls are obsolete and + * will be removed in the future. They are only preserved here for + * compatibility with existing userland utilities. + */ +#define SNAPSHOT_SET_SWAP_FILE _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int) +#define SNAPSHOT_PMOPS _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int) + +#define PMOPS_PREPARE 1 +#define PMOPS_ENTER 2 +#define PMOPS_FINISH 3 + +/* + * NOTE: The following ioctl definitions are wrong and have been replaced with + * correct ones. They are only preserved here for compatibility with existing + * userland utilities and will be removed in the future. + */ +#define SNAPSHOT_ATOMIC_SNAPSHOT _IOW(SNAPSHOT_IOC_MAGIC, 3, void *) +#define SNAPSHOT_SET_IMAGE_SIZE _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long) +#define SNAPSHOT_AVAIL_SWAP _IOR(SNAPSHOT_IOC_MAGIC, 7, void *) +#define SNAPSHOT_GET_SWAP_PAGE _IOR(SNAPSHOT_IOC_MAGIC, 8, void *) + + #define SNAPSHOT_MINOR 231 static struct snapshot_data { @@ -36,7 +59,7 @@ static struct snapshot_data { int mode; char frozen; char ready; - char platform_suspend; + char platform_support; } snapshot_state; atomic_t snapshot_device_available = ATOMIC_INIT(1); @@ -44,6 +67,7 @@ atomic_t snapshot_device_available = ATOMIC_INIT(1); static int snapshot_open(struct inode *inode, struct file *filp) { struct snapshot_data *data; + int error; if (!atomic_add_unless(&snapshot_device_available, -1, 0)) return -EBUSY; @@ -64,13 +88,23 @@ static int snapshot_open(struct inode *inode, struct file *filp) data->swap = swsusp_resume_device ? swap_type_of(swsusp_resume_device, 0, NULL) : -1; data->mode = O_RDONLY; + error = pm_notifier_call_chain(PM_RESTORE_PREPARE); + if (error) + pm_notifier_call_chain(PM_POST_RESTORE); } else { data->swap = -1; data->mode = O_WRONLY; + error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE); + if (error) + pm_notifier_call_chain(PM_POST_HIBERNATION); + } + if (error) { + atomic_inc(&snapshot_device_available); + return error; } data->frozen = 0; data->ready = 0; - data->platform_suspend = 0; + data->platform_support = 0; return 0; } @@ -88,6 +122,8 @@ static int snapshot_release(struct inode *inode, struct file *filp) thaw_processes(); mutex_unlock(&pm_mutex); } + pm_notifier_call_chain(data->mode == O_WRONLY ? + PM_POST_HIBERNATION : PM_POST_RESTORE); atomic_inc(&snapshot_device_available); return 0; } @@ -133,7 +169,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, { int error = 0; struct snapshot_data *data; - loff_t avail; + loff_t size; sector_t offset; if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC) @@ -151,18 +187,13 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, if (data->frozen) break; mutex_lock(&pm_mutex); - error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE); - if (!error) { - printk("Syncing filesystems ... "); - sys_sync(); - printk("done.\n"); - - error = freeze_processes(); - if (error) - thaw_processes(); - } + printk("Syncing filesystems ... "); + sys_sync(); + printk("done.\n"); + + error = freeze_processes(); if (error) - pm_notifier_call_chain(PM_POST_HIBERNATION); + thaw_processes(); mutex_unlock(&pm_mutex); if (!error) data->frozen = 1; @@ -173,19 +204,19 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, break; mutex_lock(&pm_mutex); thaw_processes(); - pm_notifier_call_chain(PM_POST_HIBERNATION); mutex_unlock(&pm_mutex); data->frozen = 0; break; + case SNAPSHOT_CREATE_IMAGE: case SNAPSHOT_ATOMIC_SNAPSHOT: if (data->mode != O_RDONLY || !data->frozen || data->ready) { error = -EPERM; break; } - error = hibernation_snapshot(data->platform_suspend); + error = hibernation_snapshot(data->platform_support); if (!error) - error = put_user(in_suspend, (unsigned int __user *)arg); + error = put_user(in_suspend, (int __user *)arg); if (!error) data->ready = 1; break; @@ -197,7 +228,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, error = -EPERM; break; } - error = hibernation_restore(data->platform_suspend); + error = hibernation_restore(data->platform_support); break; case SNAPSHOT_FREE: @@ -206,16 +237,29 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, data->ready = 0; break; + case SNAPSHOT_PREF_IMAGE_SIZE: case SNAPSHOT_SET_IMAGE_SIZE: image_size = arg; break; + case SNAPSHOT_GET_IMAGE_SIZE: + if (!data->ready) { + error = -ENODATA; + break; + } + size = snapshot_get_image_size(); + size <<= PAGE_SHIFT; + error = put_user(size, (loff_t __user *)arg); + break; + + case SNAPSHOT_AVAIL_SWAP_SIZE: case SNAPSHOT_AVAIL_SWAP: - avail = count_swap_pages(data->swap, 1); - avail <<= PAGE_SHIFT; - error = put_user(avail, (loff_t __user *)arg); + size = count_swap_pages(data->swap, 1); + size <<= PAGE_SHIFT; + error = put_user(size, (loff_t __user *)arg); break; + case SNAPSHOT_ALLOC_SWAP_PAGE: case SNAPSHOT_GET_SWAP_PAGE: if (data->swap < 0 || data->swap >= MAX_SWAPFILES) { error = -ENODEV; @@ -224,7 +268,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, offset = alloc_swapdev_block(data->swap); if (offset) { offset <<= PAGE_SHIFT; - error = put_user(offset, (sector_t __user *)arg); + error = put_user(offset, (loff_t __user *)arg); } else { error = -ENOSPC; } @@ -238,7 +282,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, free_all_swap_pages(data->swap); break; - case SNAPSHOT_SET_SWAP_FILE: + case SNAPSHOT_SET_SWAP_FILE: /* This ioctl is deprecated */ if (!swsusp_swap_in_use()) { /* * User space encodes device types as two-byte values, @@ -275,26 +319,33 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp, mutex_unlock(&pm_mutex); break; - case SNAPSHOT_PMOPS: + case SNAPSHOT_PLATFORM_SUPPORT: + data->platform_support = !!arg; + break; + + case SNAPSHOT_POWER_OFF: + if (data->platform_support) + error = hibernation_platform_enter(); + break; + + case SNAPSHOT_PMOPS: /* This ioctl is deprecated */ error = -EINVAL; switch (arg) { case PMOPS_PREPARE: - data->platform_suspend = 1; + data->platform_support = 1; error = 0; break; case PMOPS_ENTER: - if (data->platform_suspend) + if (data->platform_support) error = hibernation_platform_enter(); - break; case PMOPS_FINISH: - if (data->platform_suspend) + if (data->platform_support) error = 0; - break; default: diff --git a/kernel/printk.c b/kernel/printk.c index a30fe33de39..4a090621f37 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -36,6 +36,13 @@ #include <asm/uaccess.h> +/* + * Architectures can override it: + */ +void __attribute__((weak)) early_printk(const char *fmt, ...) +{ +} + #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT) /* printk's without a loglevel use this.. */ @@ -86,16 +93,16 @@ static int console_locked, console_suspended; */ static DEFINE_SPINLOCK(logbuf_lock); -#define LOG_BUF_MASK (log_buf_len-1) +#define LOG_BUF_MASK (log_buf_len-1) #define LOG_BUF(idx) (log_buf[(idx) & LOG_BUF_MASK]) /* * The indices into log_buf are not constrained to log_buf_len - they * must be masked before subscripting */ -static unsigned long log_start; /* Index into log_buf: next char to be read by syslog() */ -static unsigned long con_start; /* Index into log_buf: next char to be sent to consoles */ -static unsigned long log_end; /* Index into log_buf: most-recently-written-char + 1 */ +static unsigned log_start; /* Index into log_buf: next char to be read by syslog() */ +static unsigned con_start; /* Index into log_buf: next char to be sent to consoles */ +static unsigned log_end; /* Index into log_buf: most-recently-written-char + 1 */ /* * Array of consoles built from command line options (console=) @@ -121,17 +128,17 @@ static int console_may_schedule; static char __log_buf[__LOG_BUF_LEN]; static char *log_buf = __log_buf; static int log_buf_len = __LOG_BUF_LEN; -static unsigned long logged_chars; /* Number of chars produced since last read+clear operation */ +static unsigned logged_chars; /* Number of chars produced since last read+clear operation */ static int __init log_buf_len_setup(char *str) { - unsigned long size = memparse(str, &str); + unsigned size = memparse(str, &str); unsigned long flags; if (size) size = roundup_pow_of_two(size); if (size > log_buf_len) { - unsigned long start, dest_idx, offset; + unsigned start, dest_idx, offset; char *new_log_buf; new_log_buf = alloc_bootmem(size); @@ -288,7 +295,7 @@ int log_buf_read(int idx) */ int do_syslog(int type, char __user *buf, int len) { - unsigned long i, j, limit, count; + unsigned i, j, limit, count; int do_clear = 0; char c; int error = 0; @@ -429,7 +436,7 @@ asmlinkage long sys_syslog(int type, char __user *buf, int len) /* * Call the console drivers on a range of log_buf */ -static void __call_console_drivers(unsigned long start, unsigned long end) +static void __call_console_drivers(unsigned start, unsigned end) { struct console *con; @@ -448,16 +455,16 @@ static int __init ignore_loglevel_setup(char *str) ignore_loglevel = 1; printk(KERN_INFO "debug: ignoring loglevel setting.\n"); - return 1; + return 0; } -__setup("ignore_loglevel", ignore_loglevel_setup); +early_param("ignore_loglevel", ignore_loglevel_setup); /* * Write out chars from start to end - 1 inclusive */ -static void _call_console_drivers(unsigned long start, - unsigned long end, int msg_log_level) +static void _call_console_drivers(unsigned start, + unsigned end, int msg_log_level) { if ((msg_log_level < console_loglevel || ignore_loglevel) && console_drivers && start != end) { @@ -477,12 +484,12 @@ static void _call_console_drivers(unsigned long start, * log_buf[start] to log_buf[end - 1]. * The console_sem must be held. */ -static void call_console_drivers(unsigned long start, unsigned long end) +static void call_console_drivers(unsigned start, unsigned end) { - unsigned long cur_index, start_print; + unsigned cur_index, start_print; static int msg_level = -1; - BUG_ON(((long)(start - end)) > 0); + BUG_ON(((int)(start - end)) > 0); cur_index = start; start_print = start; @@ -573,11 +580,6 @@ static int __init printk_time_setup(char *str) __setup("time", printk_time_setup); -__attribute__((weak)) unsigned long long printk_clock(void) -{ - return sched_clock(); -} - /* Check if we have any console registered that can be called early in boot. */ static int have_callable_console(void) { @@ -628,30 +630,57 @@ asmlinkage int printk(const char *fmt, ...) /* cpu currently holding logbuf_lock */ static volatile unsigned int printk_cpu = UINT_MAX; +const char printk_recursion_bug_msg [] = + KERN_CRIT "BUG: recent printk recursion!\n"; +static int printk_recursion_bug; + asmlinkage int vprintk(const char *fmt, va_list args) { + static int log_level_unknown = 1; + static char printk_buf[1024]; + unsigned long flags; - int printed_len; + int printed_len = 0; + int this_cpu; char *p; - static char printk_buf[1024]; - static int log_level_unknown = 1; boot_delay_msec(); preempt_disable(); - if (unlikely(oops_in_progress) && printk_cpu == smp_processor_id()) - /* If a crash is occurring during printk() on this CPU, - * make sure we can't deadlock */ - zap_locks(); - /* This stops the holder of console_sem just where we want him */ raw_local_irq_save(flags); + this_cpu = smp_processor_id(); + + /* + * Ouch, printk recursed into itself! + */ + if (unlikely(printk_cpu == this_cpu)) { + /* + * If a crash is occurring during printk() on this CPU, + * then try to get the crash message out but make sure + * we can't deadlock. Otherwise just return to avoid the + * recursion and return - but flag the recursion so that + * it can be printed at the next appropriate moment: + */ + if (!oops_in_progress) { + printk_recursion_bug = 1; + goto out_restore_irqs; + } + zap_locks(); + } + lockdep_off(); spin_lock(&logbuf_lock); - printk_cpu = smp_processor_id(); + printk_cpu = this_cpu; + if (printk_recursion_bug) { + printk_recursion_bug = 0; + strcpy(printk_buf, printk_recursion_bug_msg); + printed_len = sizeof(printk_recursion_bug_msg); + } /* Emit the output into the temporary buffer */ - printed_len = vscnprintf(printk_buf, sizeof(printk_buf), fmt, args); + printed_len += vscnprintf(printk_buf + printed_len, + sizeof(printk_buf), fmt, args); /* * Copy the output into log_buf. If the caller didn't provide @@ -680,7 +709,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) loglev_char = default_message_loglevel + '0'; } - t = printk_clock(); + t = cpu_clock(printk_cpu); nanosec_rem = do_div(t, 1000000000); tlen = sprintf(tbuf, "<%c>[%5lu.%06lu] ", @@ -744,6 +773,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) printk_cpu = UINT_MAX; spin_unlock(&logbuf_lock); lockdep_on(); +out_restore_irqs: raw_local_irq_restore(flags); } @@ -760,7 +790,7 @@ asmlinkage long sys_syslog(int type, char __user *buf, int len) return -ENOSYS; } -static void call_console_drivers(unsigned long start, unsigned long end) +static void call_console_drivers(unsigned start, unsigned end) { } @@ -817,7 +847,7 @@ __setup("console=", console_setup); * commonly to provide a default console (ie from PROM variables) when * the user has not supplied one. */ -int __init add_preferred_console(char *name, int idx, char *options) +int add_preferred_console(char *name, int idx, char *options) { struct console_cmdline *c; int i; @@ -953,8 +983,8 @@ void wake_up_klogd(void) void release_console_sem(void) { unsigned long flags; - unsigned long _con_start, _log_end; - unsigned long wake_klogd = 0; + unsigned _con_start, _log_end; + unsigned wake_klogd = 0; if (console_suspended) { up(&secondary_console_sem); @@ -1245,7 +1275,7 @@ void tty_write_message(struct tty_struct *tty, char *msg) int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst) { static DEFINE_SPINLOCK(ratelimit_lock); - static unsigned long toks = 10 * 5 * HZ; + static unsigned toks = 10 * 5 * HZ; static unsigned long last_msg; static int missed; unsigned long flags; diff --git a/kernel/profile.c b/kernel/profile.c index 5e95330e512..e64c2da11c0 100644 --- a/kernel/profile.c +++ b/kernel/profile.c @@ -52,7 +52,7 @@ static DEFINE_PER_CPU(int, cpu_profile_flip); static DEFINE_MUTEX(profile_flip_mutex); #endif /* CONFIG_SMP */ -static int __init profile_setup(char * str) +static int __init profile_setup(char *str) { static char __initdata schedstr[] = "schedule"; static char __initdata sleepstr[] = "sleep"; @@ -104,28 +104,28 @@ __setup("profile=", profile_setup); void __init profile_init(void) { - if (!prof_on) + if (!prof_on) return; - + /* only text is profiled */ prof_len = (_etext - _stext) >> prof_shift; prof_buffer = alloc_bootmem(prof_len*sizeof(atomic_t)); } /* Profile event notifications */ - + #ifdef CONFIG_PROFILING - + static BLOCKING_NOTIFIER_HEAD(task_exit_notifier); static ATOMIC_NOTIFIER_HEAD(task_free_notifier); static BLOCKING_NOTIFIER_HEAD(munmap_notifier); - -void profile_task_exit(struct task_struct * task) + +void profile_task_exit(struct task_struct *task) { blocking_notifier_call_chain(&task_exit_notifier, 0, task); } - -int profile_handoff_task(struct task_struct * task) + +int profile_handoff_task(struct task_struct *task) { int ret; ret = atomic_notifier_call_chain(&task_free_notifier, 0, task); @@ -137,52 +137,55 @@ void profile_munmap(unsigned long addr) blocking_notifier_call_chain(&munmap_notifier, 0, (void *)addr); } -int task_handoff_register(struct notifier_block * n) +int task_handoff_register(struct notifier_block *n) { return atomic_notifier_chain_register(&task_free_notifier, n); } +EXPORT_SYMBOL_GPL(task_handoff_register); -int task_handoff_unregister(struct notifier_block * n) +int task_handoff_unregister(struct notifier_block *n) { return atomic_notifier_chain_unregister(&task_free_notifier, n); } +EXPORT_SYMBOL_GPL(task_handoff_unregister); -int profile_event_register(enum profile_type type, struct notifier_block * n) +int profile_event_register(enum profile_type type, struct notifier_block *n) { int err = -EINVAL; - + switch (type) { - case PROFILE_TASK_EXIT: - err = blocking_notifier_chain_register( - &task_exit_notifier, n); - break; - case PROFILE_MUNMAP: - err = blocking_notifier_chain_register( - &munmap_notifier, n); - break; + case PROFILE_TASK_EXIT: + err = blocking_notifier_chain_register( + &task_exit_notifier, n); + break; + case PROFILE_MUNMAP: + err = blocking_notifier_chain_register( + &munmap_notifier, n); + break; } - + return err; } +EXPORT_SYMBOL_GPL(profile_event_register); - -int profile_event_unregister(enum profile_type type, struct notifier_block * n) +int profile_event_unregister(enum profile_type type, struct notifier_block *n) { int err = -EINVAL; - + switch (type) { - case PROFILE_TASK_EXIT: - err = blocking_notifier_chain_unregister( - &task_exit_notifier, n); - break; - case PROFILE_MUNMAP: - err = blocking_notifier_chain_unregister( - &munmap_notifier, n); - break; + case PROFILE_TASK_EXIT: + err = blocking_notifier_chain_unregister( + &task_exit_notifier, n); + break; + case PROFILE_MUNMAP: + err = blocking_notifier_chain_unregister( + &munmap_notifier, n); + break; } return err; } +EXPORT_SYMBOL_GPL(profile_event_unregister); int register_timer_hook(int (*hook)(struct pt_regs *)) { @@ -191,6 +194,7 @@ int register_timer_hook(int (*hook)(struct pt_regs *)) timer_hook = hook; return 0; } +EXPORT_SYMBOL_GPL(register_timer_hook); void unregister_timer_hook(int (*hook)(struct pt_regs *)) { @@ -199,13 +203,7 @@ void unregister_timer_hook(int (*hook)(struct pt_regs *)) /* make sure all CPUs see the NULL hook */ synchronize_sched(); /* Allow ongoing interrupts to complete. */ } - -EXPORT_SYMBOL_GPL(register_timer_hook); EXPORT_SYMBOL_GPL(unregister_timer_hook); -EXPORT_SYMBOL_GPL(task_handoff_register); -EXPORT_SYMBOL_GPL(task_handoff_unregister); -EXPORT_SYMBOL_GPL(profile_event_register); -EXPORT_SYMBOL_GPL(profile_event_unregister); #endif /* CONFIG_PROFILING */ @@ -366,7 +364,7 @@ static int __devinit profile_cpu_callback(struct notifier_block *info, per_cpu(cpu_profile_hits, cpu)[0] = page_address(page); } break; - out_free: +out_free: page = virt_to_page(per_cpu(cpu_profile_hits, cpu)[1]); per_cpu(cpu_profile_hits, cpu)[1] = NULL; __free_page(page); @@ -409,7 +407,6 @@ void profile_hits(int type, void *__pc, unsigned int nr_hits) atomic_add(nr_hits, &prof_buffer[min(pc, prof_len - 1)]); } #endif /* !CONFIG_SMP */ - EXPORT_SYMBOL_GPL(profile_hits); void profile_tick(int type) @@ -427,7 +424,7 @@ void profile_tick(int type) #include <asm/uaccess.h> #include <asm/ptrace.h> -static int prof_cpu_mask_read_proc (char *page, char **start, off_t off, +static int prof_cpu_mask_read_proc(char *page, char **start, off_t off, int count, int *eof, void *data) { int len = cpumask_scnprintf(page, count, *(cpumask_t *)data); @@ -437,8 +434,8 @@ static int prof_cpu_mask_read_proc (char *page, char **start, off_t off, return len; } -static int prof_cpu_mask_write_proc (struct file *file, const char __user *buffer, - unsigned long count, void *data) +static int prof_cpu_mask_write_proc(struct file *file, + const char __user *buffer, unsigned long count, void *data) { cpumask_t *mask = (cpumask_t *)data; unsigned long full_count = count, err; @@ -457,7 +454,8 @@ void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir) struct proc_dir_entry *entry; /* create /proc/irq/prof_cpu_mask */ - if (!(entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir))) + entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir); + if (!entry) return; entry->data = (void *)&prof_cpu_mask; entry->read_proc = prof_cpu_mask_read_proc; @@ -475,7 +473,7 @@ read_profile(struct file *file, char __user *buf, size_t count, loff_t *ppos) { unsigned long p = *ppos; ssize_t read; - char * pnt; + char *pnt; unsigned int sample_step = 1 << prof_shift; profile_flip_buffers(); @@ -486,12 +484,12 @@ read_profile(struct file *file, char __user *buf, size_t count, loff_t *ppos) read = 0; while (p < sizeof(unsigned int) && count > 0) { - if (put_user(*((char *)(&sample_step)+p),buf)) + if (put_user(*((char *)(&sample_step)+p), buf)) return -EFAULT; buf++; p++; count--; read++; } pnt = (char *)prof_buffer + p - sizeof(atomic_t); - if (copy_to_user(buf,(void *)pnt,count)) + if (copy_to_user(buf, (void *)pnt, count)) return -EFAULT; read += count; *ppos += read; @@ -508,7 +506,7 @@ static ssize_t write_profile(struct file *file, const char __user *buf, size_t count, loff_t *ppos) { #ifdef CONFIG_SMP - extern int setup_profiling_timer (unsigned int multiplier); + extern int setup_profiling_timer(unsigned int multiplier); if (count == sizeof(int)) { unsigned int multiplier; @@ -591,7 +589,8 @@ static int __init create_proc_profile(void) return 0; if (create_hash_tables()) return -1; - if (!(entry = create_proc_entry("profile", S_IWUSR | S_IRUGO, NULL))) + entry = create_proc_entry("profile", S_IWUSR | S_IRUGO, NULL); + if (!entry) return 0; entry->proc_fops = &proc_profile_operations; entry->size = (1+prof_len) * sizeof(atomic_t); diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 7c76f2ffaea..628b03ab88a 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -20,6 +20,7 @@ #include <linux/signal.h> #include <linux/audit.h> #include <linux/pid_namespace.h> +#include <linux/syscalls.h> #include <asm/pgtable.h> #include <asm/uaccess.h> @@ -51,9 +52,9 @@ void __ptrace_link(struct task_struct *child, struct task_struct *new_parent) void ptrace_untrace(struct task_struct *child) { spin_lock(&child->sighand->siglock); - if (child->state == TASK_TRACED) { + if (task_is_traced(child)) { if (child->signal->flags & SIGNAL_STOP_STOPPED) { - child->state = TASK_STOPPED; + __set_task_state(child, TASK_STOPPED); } else { signal_wake_up(child, 1); } @@ -79,7 +80,7 @@ void __ptrace_unlink(struct task_struct *child) add_parent(child); } - if (child->state == TASK_TRACED) + if (task_is_traced(child)) ptrace_untrace(child); } @@ -103,24 +104,22 @@ int ptrace_check_attach(struct task_struct *child, int kill) && child->signal != NULL) { ret = 0; spin_lock_irq(&child->sighand->siglock); - if (child->state == TASK_STOPPED) { + if (task_is_stopped(child)) child->state = TASK_TRACED; - } else if (child->state != TASK_TRACED && !kill) { + else if (!task_is_traced(child) && !kill) ret = -ESRCH; - } spin_unlock_irq(&child->sighand->siglock); } read_unlock(&tasklist_lock); - if (!ret && !kill) { + if (!ret && !kill) wait_task_inactive(child); - } /* All systems go.. */ return ret; } -static int may_attach(struct task_struct *task) +int __ptrace_may_attach(struct task_struct *task) { /* May we inspect the given task? * This check is used both for attaching with ptrace @@ -154,7 +153,7 @@ int ptrace_may_attach(struct task_struct *task) { int err; task_lock(task); - err = may_attach(task); + err = __ptrace_may_attach(task); task_unlock(task); return !err; } @@ -196,7 +195,7 @@ repeat: /* the same process cannot be attached many times */ if (task->ptrace & PT_PTRACED) goto bad; - retval = may_attach(task); + retval = __ptrace_may_attach(task); if (retval) goto bad; @@ -366,12 +365,73 @@ static int ptrace_setsiginfo(struct task_struct *child, siginfo_t __user * data) return error; } + +#ifdef PTRACE_SINGLESTEP +#define is_singlestep(request) ((request) == PTRACE_SINGLESTEP) +#else +#define is_singlestep(request) 0 +#endif + +#ifdef PTRACE_SINGLEBLOCK +#define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK) +#else +#define is_singleblock(request) 0 +#endif + +#ifdef PTRACE_SYSEMU +#define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP) +#else +#define is_sysemu_singlestep(request) 0 +#endif + +static int ptrace_resume(struct task_struct *child, long request, long data) +{ + if (!valid_signal(data)) + return -EIO; + + if (request == PTRACE_SYSCALL) + set_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + else + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); + +#ifdef TIF_SYSCALL_EMU + if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP) + set_tsk_thread_flag(child, TIF_SYSCALL_EMU); + else + clear_tsk_thread_flag(child, TIF_SYSCALL_EMU); +#endif + + if (is_singleblock(request)) { + if (unlikely(!arch_has_block_step())) + return -EIO; + user_enable_block_step(child); + } else if (is_singlestep(request) || is_sysemu_singlestep(request)) { + if (unlikely(!arch_has_single_step())) + return -EIO; + user_enable_single_step(child); + } + else + user_disable_single_step(child); + + child->exit_code = data; + wake_up_process(child); + + return 0; +} + int ptrace_request(struct task_struct *child, long request, long addr, long data) { int ret = -EIO; switch (request) { + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: + return generic_ptrace_peekdata(child, addr, data); + case PTRACE_POKETEXT: + case PTRACE_POKEDATA: + return generic_ptrace_pokedata(child, addr, data); + #ifdef PTRACE_OLDSETOPTIONS case PTRACE_OLDSETOPTIONS: #endif @@ -390,6 +450,26 @@ int ptrace_request(struct task_struct *child, long request, case PTRACE_DETACH: /* detach a process that was attached. */ ret = ptrace_detach(child, data); break; + +#ifdef PTRACE_SINGLESTEP + case PTRACE_SINGLESTEP: +#endif +#ifdef PTRACE_SINGLEBLOCK + case PTRACE_SINGLEBLOCK: +#endif +#ifdef PTRACE_SYSEMU + case PTRACE_SYSEMU: + case PTRACE_SYSEMU_SINGLESTEP: +#endif + case PTRACE_SYSCALL: + case PTRACE_CONT: + return ptrace_resume(child, request, data); + + case PTRACE_KILL: + if (child->exit_state) /* already dead */ + return 0; + return ptrace_resume(child, request, SIGKILL); + default: break; } @@ -470,6 +550,8 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data) lock_kernel(); if (request == PTRACE_TRACEME) { ret = ptrace_traceme(); + if (!ret) + arch_ptrace_attach(current); goto out; } @@ -524,3 +606,87 @@ int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data) copied = access_process_vm(tsk, addr, &data, sizeof(data), 1); return (copied == sizeof(data)) ? 0 : -EIO; } + +#ifdef CONFIG_COMPAT +#include <linux/compat.h> + +int compat_ptrace_request(struct task_struct *child, compat_long_t request, + compat_ulong_t addr, compat_ulong_t data) +{ + compat_ulong_t __user *datap = compat_ptr(data); + compat_ulong_t word; + int ret; + + switch (request) { + case PTRACE_PEEKTEXT: + case PTRACE_PEEKDATA: + ret = access_process_vm(child, addr, &word, sizeof(word), 0); + if (ret != sizeof(word)) + ret = -EIO; + else + ret = put_user(word, datap); + break; + + case PTRACE_POKETEXT: + case PTRACE_POKEDATA: + ret = access_process_vm(child, addr, &data, sizeof(data), 1); + ret = (ret != sizeof(data) ? -EIO : 0); + break; + + case PTRACE_GETEVENTMSG: + ret = put_user((compat_ulong_t) child->ptrace_message, datap); + break; + + default: + ret = ptrace_request(child, request, addr, data); + } + + return ret; +} + +#ifdef __ARCH_WANT_COMPAT_SYS_PTRACE +asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid, + compat_long_t addr, compat_long_t data) +{ + struct task_struct *child; + long ret; + + /* + * This lock_kernel fixes a subtle race with suid exec + */ + lock_kernel(); + if (request == PTRACE_TRACEME) { + ret = ptrace_traceme(); + goto out; + } + + child = ptrace_get_task_struct(pid); + if (IS_ERR(child)) { + ret = PTR_ERR(child); + goto out; + } + + if (request == PTRACE_ATTACH) { + ret = ptrace_attach(child); + /* + * Some architectures need to do book-keeping after + * a ptrace attach. + */ + if (!ret) + arch_ptrace_attach(child); + goto out_put_task_struct; + } + + ret = ptrace_check_attach(child, request == PTRACE_KILL); + if (!ret) + ret = compat_arch_ptrace(child, request, addr, data); + + out_put_task_struct: + put_task_struct(child); + out: + unlock_kernel(); + return ret; +} +#endif /* __ARCH_WANT_COMPAT_SYS_PTRACE */ + +#endif /* CONFIG_COMPAT */ diff --git a/kernel/rcuclassic.c b/kernel/rcuclassic.c new file mode 100644 index 00000000000..f4ffbd0f306 --- /dev/null +++ b/kernel/rcuclassic.c @@ -0,0 +1,575 @@ +/* + * Read-Copy Update mechanism for mutual exclusion + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright IBM Corporation, 2001 + * + * Authors: Dipankar Sarma <dipankar@in.ibm.com> + * Manfred Spraul <manfred@colorfullife.com> + * + * Based on the original work by Paul McKenney <paulmck@us.ibm.com> + * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen. + * Papers: + * http://www.rdrop.com/users/paulmck/paper/rclockpdcsproof.pdf + * http://lse.sourceforge.net/locking/rclock_OLS.2001.05.01c.sc.pdf (OLS2001) + * + * For detailed explanation of Read-Copy Update mechanism see - + * Documentation/RCU + * + */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/smp.h> +#include <linux/rcupdate.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <asm/atomic.h> +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/completion.h> +#include <linux/moduleparam.h> +#include <linux/percpu.h> +#include <linux/notifier.h> +#include <linux/cpu.h> +#include <linux/mutex.h> + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +static struct lock_class_key rcu_lock_key; +struct lockdep_map rcu_lock_map = + STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key); +EXPORT_SYMBOL_GPL(rcu_lock_map); +#endif + + +/* Definition for rcupdate control block. */ +static struct rcu_ctrlblk rcu_ctrlblk = { + .cur = -300, + .completed = -300, + .lock = __SPIN_LOCK_UNLOCKED(&rcu_ctrlblk.lock), + .cpumask = CPU_MASK_NONE, +}; +static struct rcu_ctrlblk rcu_bh_ctrlblk = { + .cur = -300, + .completed = -300, + .lock = __SPIN_LOCK_UNLOCKED(&rcu_bh_ctrlblk.lock), + .cpumask = CPU_MASK_NONE, +}; + +DEFINE_PER_CPU(struct rcu_data, rcu_data) = { 0L }; +DEFINE_PER_CPU(struct rcu_data, rcu_bh_data) = { 0L }; + +static int blimit = 10; +static int qhimark = 10000; +static int qlowmark = 100; + +#ifdef CONFIG_SMP +static void force_quiescent_state(struct rcu_data *rdp, + struct rcu_ctrlblk *rcp) +{ + int cpu; + cpumask_t cpumask; + set_need_resched(); + if (unlikely(!rcp->signaled)) { + rcp->signaled = 1; + /* + * Don't send IPI to itself. With irqs disabled, + * rdp->cpu is the current cpu. + */ + cpumask = rcp->cpumask; + cpu_clear(rdp->cpu, cpumask); + for_each_cpu_mask(cpu, cpumask) + smp_send_reschedule(cpu); + } +} +#else +static inline void force_quiescent_state(struct rcu_data *rdp, + struct rcu_ctrlblk *rcp) +{ + set_need_resched(); +} +#endif + +/** + * call_rcu - Queue an RCU callback for invocation after a grace period. + * @head: structure to be used for queueing the RCU updates. + * @func: actual update function to be invoked after the grace period + * + * The update function will be invoked some time after a full grace + * period elapses, in other words after all currently executing RCU + * read-side critical sections have completed. RCU read-side critical + * sections are delimited by rcu_read_lock() and rcu_read_unlock(), + * and may be nested. + */ +void call_rcu(struct rcu_head *head, + void (*func)(struct rcu_head *rcu)) +{ + unsigned long flags; + struct rcu_data *rdp; + + head->func = func; + head->next = NULL; + local_irq_save(flags); + rdp = &__get_cpu_var(rcu_data); + *rdp->nxttail = head; + rdp->nxttail = &head->next; + if (unlikely(++rdp->qlen > qhimark)) { + rdp->blimit = INT_MAX; + force_quiescent_state(rdp, &rcu_ctrlblk); + } + local_irq_restore(flags); +} +EXPORT_SYMBOL_GPL(call_rcu); + +/** + * call_rcu_bh - Queue an RCU for invocation after a quicker grace period. + * @head: structure to be used for queueing the RCU updates. + * @func: actual update function to be invoked after the grace period + * + * The update function will be invoked some time after a full grace + * period elapses, in other words after all currently executing RCU + * read-side critical sections have completed. call_rcu_bh() assumes + * that the read-side critical sections end on completion of a softirq + * handler. This means that read-side critical sections in process + * context must not be interrupted by softirqs. This interface is to be + * used when most of the read-side critical sections are in softirq context. + * RCU read-side critical sections are delimited by rcu_read_lock() and + * rcu_read_unlock(), * if in interrupt context or rcu_read_lock_bh() + * and rcu_read_unlock_bh(), if in process context. These may be nested. + */ +void call_rcu_bh(struct rcu_head *head, + void (*func)(struct rcu_head *rcu)) +{ + unsigned long flags; + struct rcu_data *rdp; + + head->func = func; + head->next = NULL; + local_irq_save(flags); + rdp = &__get_cpu_var(rcu_bh_data); + *rdp->nxttail = head; + rdp->nxttail = &head->next; + + if (unlikely(++rdp->qlen > qhimark)) { + rdp->blimit = INT_MAX; + force_quiescent_state(rdp, &rcu_bh_ctrlblk); + } + + local_irq_restore(flags); +} +EXPORT_SYMBOL_GPL(call_rcu_bh); + +/* + * Return the number of RCU batches processed thus far. Useful + * for debug and statistics. + */ +long rcu_batches_completed(void) +{ + return rcu_ctrlblk.completed; +} +EXPORT_SYMBOL_GPL(rcu_batches_completed); + +/* + * Return the number of RCU batches processed thus far. Useful + * for debug and statistics. + */ +long rcu_batches_completed_bh(void) +{ + return rcu_bh_ctrlblk.completed; +} +EXPORT_SYMBOL_GPL(rcu_batches_completed_bh); + +/* Raises the softirq for processing rcu_callbacks. */ +static inline void raise_rcu_softirq(void) +{ + raise_softirq(RCU_SOFTIRQ); + /* + * The smp_mb() here is required to ensure that this cpu's + * __rcu_process_callbacks() reads the most recently updated + * value of rcu->cur. + */ + smp_mb(); +} + +/* + * Invoke the completed RCU callbacks. They are expected to be in + * a per-cpu list. + */ +static void rcu_do_batch(struct rcu_data *rdp) +{ + struct rcu_head *next, *list; + int count = 0; + + list = rdp->donelist; + while (list) { + next = list->next; + prefetch(next); + list->func(list); + list = next; + if (++count >= rdp->blimit) + break; + } + rdp->donelist = list; + + local_irq_disable(); + rdp->qlen -= count; + local_irq_enable(); + if (rdp->blimit == INT_MAX && rdp->qlen <= qlowmark) + rdp->blimit = blimit; + + if (!rdp->donelist) + rdp->donetail = &rdp->donelist; + else + raise_rcu_softirq(); +} + +/* + * Grace period handling: + * The grace period handling consists out of two steps: + * - A new grace period is started. + * This is done by rcu_start_batch. The start is not broadcasted to + * all cpus, they must pick this up by comparing rcp->cur with + * rdp->quiescbatch. All cpus are recorded in the + * rcu_ctrlblk.cpumask bitmap. + * - All cpus must go through a quiescent state. + * Since the start of the grace period is not broadcasted, at least two + * calls to rcu_check_quiescent_state are required: + * The first call just notices that a new grace period is running. The + * following calls check if there was a quiescent state since the beginning + * of the grace period. If so, it updates rcu_ctrlblk.cpumask. If + * the bitmap is empty, then the grace period is completed. + * rcu_check_quiescent_state calls rcu_start_batch(0) to start the next grace + * period (if necessary). + */ +/* + * Register a new batch of callbacks, and start it up if there is currently no + * active batch and the batch to be registered has not already occurred. + * Caller must hold rcu_ctrlblk.lock. + */ +static void rcu_start_batch(struct rcu_ctrlblk *rcp) +{ + if (rcp->next_pending && + rcp->completed == rcp->cur) { + rcp->next_pending = 0; + /* + * next_pending == 0 must be visible in + * __rcu_process_callbacks() before it can see new value of cur. + */ + smp_wmb(); + rcp->cur++; + + /* + * Accessing nohz_cpu_mask before incrementing rcp->cur needs a + * Barrier Otherwise it can cause tickless idle CPUs to be + * included in rcp->cpumask, which will extend graceperiods + * unnecessarily. + */ + smp_mb(); + cpus_andnot(rcp->cpumask, cpu_online_map, nohz_cpu_mask); + + rcp->signaled = 0; + } +} + +/* + * cpu went through a quiescent state since the beginning of the grace period. + * Clear it from the cpu mask and complete the grace period if it was the last + * cpu. Start another grace period if someone has further entries pending + */ +static void cpu_quiet(int cpu, struct rcu_ctrlblk *rcp) +{ + cpu_clear(cpu, rcp->cpumask); + if (cpus_empty(rcp->cpumask)) { + /* batch completed ! */ + rcp->completed = rcp->cur; + rcu_start_batch(rcp); + } +} + +/* + * Check if the cpu has gone through a quiescent state (say context + * switch). If so and if it already hasn't done so in this RCU + * quiescent cycle, then indicate that it has done so. + */ +static void rcu_check_quiescent_state(struct rcu_ctrlblk *rcp, + struct rcu_data *rdp) +{ + if (rdp->quiescbatch != rcp->cur) { + /* start new grace period: */ + rdp->qs_pending = 1; + rdp->passed_quiesc = 0; + rdp->quiescbatch = rcp->cur; + return; + } + + /* Grace period already completed for this cpu? + * qs_pending is checked instead of the actual bitmap to avoid + * cacheline trashing. + */ + if (!rdp->qs_pending) + return; + + /* + * Was there a quiescent state since the beginning of the grace + * period? If no, then exit and wait for the next call. + */ + if (!rdp->passed_quiesc) + return; + rdp->qs_pending = 0; + + spin_lock(&rcp->lock); + /* + * rdp->quiescbatch/rcp->cur and the cpu bitmap can come out of sync + * during cpu startup. Ignore the quiescent state. + */ + if (likely(rdp->quiescbatch == rcp->cur)) + cpu_quiet(rdp->cpu, rcp); + + spin_unlock(&rcp->lock); +} + + +#ifdef CONFIG_HOTPLUG_CPU + +/* warning! helper for rcu_offline_cpu. do not use elsewhere without reviewing + * locking requirements, the list it's pulling from has to belong to a cpu + * which is dead and hence not processing interrupts. + */ +static void rcu_move_batch(struct rcu_data *this_rdp, struct rcu_head *list, + struct rcu_head **tail) +{ + local_irq_disable(); + *this_rdp->nxttail = list; + if (list) + this_rdp->nxttail = tail; + local_irq_enable(); +} + +static void __rcu_offline_cpu(struct rcu_data *this_rdp, + struct rcu_ctrlblk *rcp, struct rcu_data *rdp) +{ + /* if the cpu going offline owns the grace period + * we can block indefinitely waiting for it, so flush + * it here + */ + spin_lock_bh(&rcp->lock); + if (rcp->cur != rcp->completed) + cpu_quiet(rdp->cpu, rcp); + spin_unlock_bh(&rcp->lock); + rcu_move_batch(this_rdp, rdp->donelist, rdp->donetail); + rcu_move_batch(this_rdp, rdp->curlist, rdp->curtail); + rcu_move_batch(this_rdp, rdp->nxtlist, rdp->nxttail); +} + +static void rcu_offline_cpu(int cpu) +{ + struct rcu_data *this_rdp = &get_cpu_var(rcu_data); + struct rcu_data *this_bh_rdp = &get_cpu_var(rcu_bh_data); + + __rcu_offline_cpu(this_rdp, &rcu_ctrlblk, + &per_cpu(rcu_data, cpu)); + __rcu_offline_cpu(this_bh_rdp, &rcu_bh_ctrlblk, + &per_cpu(rcu_bh_data, cpu)); + put_cpu_var(rcu_data); + put_cpu_var(rcu_bh_data); +} + +#else + +static void rcu_offline_cpu(int cpu) +{ +} + +#endif + +/* + * This does the RCU processing work from softirq context. + */ +static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp, + struct rcu_data *rdp) +{ + if (rdp->curlist && !rcu_batch_before(rcp->completed, rdp->batch)) { + *rdp->donetail = rdp->curlist; + rdp->donetail = rdp->curtail; + rdp->curlist = NULL; + rdp->curtail = &rdp->curlist; + } + + if (rdp->nxtlist && !rdp->curlist) { + local_irq_disable(); + rdp->curlist = rdp->nxtlist; + rdp->curtail = rdp->nxttail; + rdp->nxtlist = NULL; + rdp->nxttail = &rdp->nxtlist; + local_irq_enable(); + + /* + * start the next batch of callbacks + */ + + /* determine batch number */ + rdp->batch = rcp->cur + 1; + /* see the comment and corresponding wmb() in + * the rcu_start_batch() + */ + smp_rmb(); + + if (!rcp->next_pending) { + /* and start it/schedule start if it's a new batch */ + spin_lock(&rcp->lock); + rcp->next_pending = 1; + rcu_start_batch(rcp); + spin_unlock(&rcp->lock); + } + } + + rcu_check_quiescent_state(rcp, rdp); + if (rdp->donelist) + rcu_do_batch(rdp); +} + +static void rcu_process_callbacks(struct softirq_action *unused) +{ + __rcu_process_callbacks(&rcu_ctrlblk, &__get_cpu_var(rcu_data)); + __rcu_process_callbacks(&rcu_bh_ctrlblk, &__get_cpu_var(rcu_bh_data)); +} + +static int __rcu_pending(struct rcu_ctrlblk *rcp, struct rcu_data *rdp) +{ + /* This cpu has pending rcu entries and the grace period + * for them has completed. + */ + if (rdp->curlist && !rcu_batch_before(rcp->completed, rdp->batch)) + return 1; + + /* This cpu has no pending entries, but there are new entries */ + if (!rdp->curlist && rdp->nxtlist) + return 1; + + /* This cpu has finished callbacks to invoke */ + if (rdp->donelist) + return 1; + + /* The rcu core waits for a quiescent state from the cpu */ + if (rdp->quiescbatch != rcp->cur || rdp->qs_pending) + return 1; + + /* nothing to do */ + return 0; +} + +/* + * Check to see if there is any immediate RCU-related work to be done + * by the current CPU, returning 1 if so. This function is part of the + * RCU implementation; it is -not- an exported member of the RCU API. + */ +int rcu_pending(int cpu) +{ + return __rcu_pending(&rcu_ctrlblk, &per_cpu(rcu_data, cpu)) || + __rcu_pending(&rcu_bh_ctrlblk, &per_cpu(rcu_bh_data, cpu)); +} + +/* + * Check to see if any future RCU-related work will need to be done + * by the current CPU, even if none need be done immediately, returning + * 1 if so. This function is part of the RCU implementation; it is -not- + * an exported member of the RCU API. + */ +int rcu_needs_cpu(int cpu) +{ + struct rcu_data *rdp = &per_cpu(rcu_data, cpu); + struct rcu_data *rdp_bh = &per_cpu(rcu_bh_data, cpu); + + return (!!rdp->curlist || !!rdp_bh->curlist || rcu_pending(cpu)); +} + +void rcu_check_callbacks(int cpu, int user) +{ + if (user || + (idle_cpu(cpu) && !in_softirq() && + hardirq_count() <= (1 << HARDIRQ_SHIFT))) { + rcu_qsctr_inc(cpu); + rcu_bh_qsctr_inc(cpu); + } else if (!in_softirq()) + rcu_bh_qsctr_inc(cpu); + raise_rcu_softirq(); +} + +static void rcu_init_percpu_data(int cpu, struct rcu_ctrlblk *rcp, + struct rcu_data *rdp) +{ + memset(rdp, 0, sizeof(*rdp)); + rdp->curtail = &rdp->curlist; + rdp->nxttail = &rdp->nxtlist; + rdp->donetail = &rdp->donelist; + rdp->quiescbatch = rcp->completed; + rdp->qs_pending = 0; + rdp->cpu = cpu; + rdp->blimit = blimit; +} + +static void __cpuinit rcu_online_cpu(int cpu) +{ + struct rcu_data *rdp = &per_cpu(rcu_data, cpu); + struct rcu_data *bh_rdp = &per_cpu(rcu_bh_data, cpu); + + rcu_init_percpu_data(cpu, &rcu_ctrlblk, rdp); + rcu_init_percpu_data(cpu, &rcu_bh_ctrlblk, bh_rdp); + open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL); +} + +static int __cpuinit rcu_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + long cpu = (long)hcpu; + + switch (action) { + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: + rcu_online_cpu(cpu); + break; + case CPU_DEAD: + case CPU_DEAD_FROZEN: + rcu_offline_cpu(cpu); + break; + default: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata rcu_nb = { + .notifier_call = rcu_cpu_notify, +}; + +/* + * Initializes rcu mechanism. Assumed to be called early. + * That is before local timer(SMP) or jiffie timer (uniproc) is setup. + * Note that rcu_qsctr and friends are implicitly + * initialized due to the choice of ``0'' for RCU_CTR_INVALID. + */ +void __init __rcu_init(void) +{ + rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE, + (void *)(long)smp_processor_id()); + /* Register notifier for non-boot CPUs */ + register_cpu_notifier(&rcu_nb); +} + +module_param(blimit, int, 0); +module_param(qhimark, int, 0); +module_param(qlowmark, int, 0); diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c index a66d4d1615f..760dfc233a0 100644 --- a/kernel/rcupdate.c +++ b/kernel/rcupdate.c @@ -15,7 +15,7 @@ * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * - * Copyright (C) IBM Corporation, 2001 + * Copyright IBM Corporation, 2001 * * Authors: Dipankar Sarma <dipankar@in.ibm.com> * Manfred Spraul <manfred@colorfullife.com> @@ -35,165 +35,57 @@ #include <linux/init.h> #include <linux/spinlock.h> #include <linux/smp.h> -#include <linux/rcupdate.h> #include <linux/interrupt.h> #include <linux/sched.h> #include <asm/atomic.h> #include <linux/bitops.h> -#include <linux/module.h> #include <linux/completion.h> -#include <linux/moduleparam.h> #include <linux/percpu.h> #include <linux/notifier.h> #include <linux/cpu.h> #include <linux/mutex.h> +#include <linux/module.h> -#ifdef CONFIG_DEBUG_LOCK_ALLOC -static struct lock_class_key rcu_lock_key; -struct lockdep_map rcu_lock_map = - STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key); - -EXPORT_SYMBOL_GPL(rcu_lock_map); -#endif - -/* Definition for rcupdate control block. */ -static struct rcu_ctrlblk rcu_ctrlblk = { - .cur = -300, - .completed = -300, - .lock = __SPIN_LOCK_UNLOCKED(&rcu_ctrlblk.lock), - .cpumask = CPU_MASK_NONE, -}; -static struct rcu_ctrlblk rcu_bh_ctrlblk = { - .cur = -300, - .completed = -300, - .lock = __SPIN_LOCK_UNLOCKED(&rcu_bh_ctrlblk.lock), - .cpumask = CPU_MASK_NONE, +struct rcu_synchronize { + struct rcu_head head; + struct completion completion; }; -DEFINE_PER_CPU(struct rcu_data, rcu_data) = { 0L }; -DEFINE_PER_CPU(struct rcu_data, rcu_bh_data) = { 0L }; - -/* Fake initialization required by compiler */ -static DEFINE_PER_CPU(struct tasklet_struct, rcu_tasklet) = {NULL}; -static int blimit = 10; -static int qhimark = 10000; -static int qlowmark = 100; - +static DEFINE_PER_CPU(struct rcu_head, rcu_barrier_head) = {NULL}; static atomic_t rcu_barrier_cpu_count; static DEFINE_MUTEX(rcu_barrier_mutex); static struct completion rcu_barrier_completion; -#ifdef CONFIG_SMP -static void force_quiescent_state(struct rcu_data *rdp, - struct rcu_ctrlblk *rcp) -{ - int cpu; - cpumask_t cpumask; - set_need_resched(); - if (unlikely(!rcp->signaled)) { - rcp->signaled = 1; - /* - * Don't send IPI to itself. With irqs disabled, - * rdp->cpu is the current cpu. - */ - cpumask = rcp->cpumask; - cpu_clear(rdp->cpu, cpumask); - for_each_cpu_mask(cpu, cpumask) - smp_send_reschedule(cpu); - } -} -#else -static inline void force_quiescent_state(struct rcu_data *rdp, - struct rcu_ctrlblk *rcp) +/* Because of FASTCALL declaration of complete, we use this wrapper */ +static void wakeme_after_rcu(struct rcu_head *head) { - set_need_resched(); + struct rcu_synchronize *rcu; + + rcu = container_of(head, struct rcu_synchronize, head); + complete(&rcu->completion); } -#endif /** - * call_rcu - Queue an RCU callback for invocation after a grace period. - * @head: structure to be used for queueing the RCU updates. - * @func: actual update function to be invoked after the grace period + * synchronize_rcu - wait until a grace period has elapsed. * - * The update function will be invoked some time after a full grace - * period elapses, in other words after all currently executing RCU + * Control will return to the caller some time after a full grace + * period has elapsed, in other words after all currently executing RCU * read-side critical sections have completed. RCU read-side critical * sections are delimited by rcu_read_lock() and rcu_read_unlock(), * and may be nested. */ -void fastcall call_rcu(struct rcu_head *head, - void (*func)(struct rcu_head *rcu)) -{ - unsigned long flags; - struct rcu_data *rdp; - - head->func = func; - head->next = NULL; - local_irq_save(flags); - rdp = &__get_cpu_var(rcu_data); - *rdp->nxttail = head; - rdp->nxttail = &head->next; - if (unlikely(++rdp->qlen > qhimark)) { - rdp->blimit = INT_MAX; - force_quiescent_state(rdp, &rcu_ctrlblk); - } - local_irq_restore(flags); -} - -/** - * call_rcu_bh - Queue an RCU for invocation after a quicker grace period. - * @head: structure to be used for queueing the RCU updates. - * @func: actual update function to be invoked after the grace period - * - * The update function will be invoked some time after a full grace - * period elapses, in other words after all currently executing RCU - * read-side critical sections have completed. call_rcu_bh() assumes - * that the read-side critical sections end on completion of a softirq - * handler. This means that read-side critical sections in process - * context must not be interrupted by softirqs. This interface is to be - * used when most of the read-side critical sections are in softirq context. - * RCU read-side critical sections are delimited by rcu_read_lock() and - * rcu_read_unlock(), * if in interrupt context or rcu_read_lock_bh() - * and rcu_read_unlock_bh(), if in process context. These may be nested. - */ -void fastcall call_rcu_bh(struct rcu_head *head, - void (*func)(struct rcu_head *rcu)) +void synchronize_rcu(void) { - unsigned long flags; - struct rcu_data *rdp; - - head->func = func; - head->next = NULL; - local_irq_save(flags); - rdp = &__get_cpu_var(rcu_bh_data); - *rdp->nxttail = head; - rdp->nxttail = &head->next; - - if (unlikely(++rdp->qlen > qhimark)) { - rdp->blimit = INT_MAX; - force_quiescent_state(rdp, &rcu_bh_ctrlblk); - } - - local_irq_restore(flags); -} + struct rcu_synchronize rcu; -/* - * Return the number of RCU batches processed thus far. Useful - * for debug and statistics. - */ -long rcu_batches_completed(void) -{ - return rcu_ctrlblk.completed; -} + init_completion(&rcu.completion); + /* Will wake me after RCU finished */ + call_rcu(&rcu.head, wakeme_after_rcu); -/* - * Return the number of RCU batches processed thus far. Useful - * for debug and statistics. - */ -long rcu_batches_completed_bh(void) -{ - return rcu_bh_ctrlblk.completed; + /* Wait for it */ + wait_for_completion(&rcu.completion); } +EXPORT_SYMBOL_GPL(synchronize_rcu); static void rcu_barrier_callback(struct rcu_head *notused) { @@ -207,10 +99,8 @@ static void rcu_barrier_callback(struct rcu_head *notused) static void rcu_barrier_func(void *notused) { int cpu = smp_processor_id(); - struct rcu_data *rdp = &per_cpu(rcu_data, cpu); - struct rcu_head *head; + struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu); - head = &rdp->barrier; atomic_inc(&rcu_barrier_cpu_count); call_rcu(head, rcu_barrier_callback); } @@ -225,420 +115,24 @@ void rcu_barrier(void) mutex_lock(&rcu_barrier_mutex); init_completion(&rcu_barrier_completion); atomic_set(&rcu_barrier_cpu_count, 0); + /* + * The queueing of callbacks in all CPUs must be atomic with + * respect to RCU, otherwise one CPU may queue a callback, + * wait for a grace period, decrement barrier count and call + * complete(), while other CPUs have not yet queued anything. + * So, we need to make sure that grace periods cannot complete + * until all the callbacks are queued. + */ + rcu_read_lock(); on_each_cpu(rcu_barrier_func, NULL, 0, 1); + rcu_read_unlock(); wait_for_completion(&rcu_barrier_completion); mutex_unlock(&rcu_barrier_mutex); } EXPORT_SYMBOL_GPL(rcu_barrier); -/* - * Invoke the completed RCU callbacks. They are expected to be in - * a per-cpu list. - */ -static void rcu_do_batch(struct rcu_data *rdp) -{ - struct rcu_head *next, *list; - int count = 0; - - list = rdp->donelist; - while (list) { - next = list->next; - prefetch(next); - list->func(list); - list = next; - if (++count >= rdp->blimit) - break; - } - rdp->donelist = list; - - local_irq_disable(); - rdp->qlen -= count; - local_irq_enable(); - if (rdp->blimit == INT_MAX && rdp->qlen <= qlowmark) - rdp->blimit = blimit; - - if (!rdp->donelist) - rdp->donetail = &rdp->donelist; - else - tasklet_schedule(&per_cpu(rcu_tasklet, rdp->cpu)); -} - -/* - * Grace period handling: - * The grace period handling consists out of two steps: - * - A new grace period is started. - * This is done by rcu_start_batch. The start is not broadcasted to - * all cpus, they must pick this up by comparing rcp->cur with - * rdp->quiescbatch. All cpus are recorded in the - * rcu_ctrlblk.cpumask bitmap. - * - All cpus must go through a quiescent state. - * Since the start of the grace period is not broadcasted, at least two - * calls to rcu_check_quiescent_state are required: - * The first call just notices that a new grace period is running. The - * following calls check if there was a quiescent state since the beginning - * of the grace period. If so, it updates rcu_ctrlblk.cpumask. If - * the bitmap is empty, then the grace period is completed. - * rcu_check_quiescent_state calls rcu_start_batch(0) to start the next grace - * period (if necessary). - */ -/* - * Register a new batch of callbacks, and start it up if there is currently no - * active batch and the batch to be registered has not already occurred. - * Caller must hold rcu_ctrlblk.lock. - */ -static void rcu_start_batch(struct rcu_ctrlblk *rcp) -{ - if (rcp->next_pending && - rcp->completed == rcp->cur) { - rcp->next_pending = 0; - /* - * next_pending == 0 must be visible in - * __rcu_process_callbacks() before it can see new value of cur. - */ - smp_wmb(); - rcp->cur++; - - /* - * Accessing nohz_cpu_mask before incrementing rcp->cur needs a - * Barrier Otherwise it can cause tickless idle CPUs to be - * included in rcp->cpumask, which will extend graceperiods - * unnecessarily. - */ - smp_mb(); - cpus_andnot(rcp->cpumask, cpu_online_map, nohz_cpu_mask); - - rcp->signaled = 0; - } -} - -/* - * cpu went through a quiescent state since the beginning of the grace period. - * Clear it from the cpu mask and complete the grace period if it was the last - * cpu. Start another grace period if someone has further entries pending - */ -static void cpu_quiet(int cpu, struct rcu_ctrlblk *rcp) -{ - cpu_clear(cpu, rcp->cpumask); - if (cpus_empty(rcp->cpumask)) { - /* batch completed ! */ - rcp->completed = rcp->cur; - rcu_start_batch(rcp); - } -} - -/* - * Check if the cpu has gone through a quiescent state (say context - * switch). If so and if it already hasn't done so in this RCU - * quiescent cycle, then indicate that it has done so. - */ -static void rcu_check_quiescent_state(struct rcu_ctrlblk *rcp, - struct rcu_data *rdp) -{ - if (rdp->quiescbatch != rcp->cur) { - /* start new grace period: */ - rdp->qs_pending = 1; - rdp->passed_quiesc = 0; - rdp->quiescbatch = rcp->cur; - return; - } - - /* Grace period already completed for this cpu? - * qs_pending is checked instead of the actual bitmap to avoid - * cacheline trashing. - */ - if (!rdp->qs_pending) - return; - - /* - * Was there a quiescent state since the beginning of the grace - * period? If no, then exit and wait for the next call. - */ - if (!rdp->passed_quiesc) - return; - rdp->qs_pending = 0; - - spin_lock(&rcp->lock); - /* - * rdp->quiescbatch/rcp->cur and the cpu bitmap can come out of sync - * during cpu startup. Ignore the quiescent state. - */ - if (likely(rdp->quiescbatch == rcp->cur)) - cpu_quiet(rdp->cpu, rcp); - - spin_unlock(&rcp->lock); -} - - -#ifdef CONFIG_HOTPLUG_CPU - -/* warning! helper for rcu_offline_cpu. do not use elsewhere without reviewing - * locking requirements, the list it's pulling from has to belong to a cpu - * which is dead and hence not processing interrupts. - */ -static void rcu_move_batch(struct rcu_data *this_rdp, struct rcu_head *list, - struct rcu_head **tail) -{ - local_irq_disable(); - *this_rdp->nxttail = list; - if (list) - this_rdp->nxttail = tail; - local_irq_enable(); -} - -static void __rcu_offline_cpu(struct rcu_data *this_rdp, - struct rcu_ctrlblk *rcp, struct rcu_data *rdp) -{ - /* if the cpu going offline owns the grace period - * we can block indefinitely waiting for it, so flush - * it here - */ - spin_lock_bh(&rcp->lock); - if (rcp->cur != rcp->completed) - cpu_quiet(rdp->cpu, rcp); - spin_unlock_bh(&rcp->lock); - rcu_move_batch(this_rdp, rdp->curlist, rdp->curtail); - rcu_move_batch(this_rdp, rdp->nxtlist, rdp->nxttail); - rcu_move_batch(this_rdp, rdp->donelist, rdp->donetail); -} - -static void rcu_offline_cpu(int cpu) -{ - struct rcu_data *this_rdp = &get_cpu_var(rcu_data); - struct rcu_data *this_bh_rdp = &get_cpu_var(rcu_bh_data); - - __rcu_offline_cpu(this_rdp, &rcu_ctrlblk, - &per_cpu(rcu_data, cpu)); - __rcu_offline_cpu(this_bh_rdp, &rcu_bh_ctrlblk, - &per_cpu(rcu_bh_data, cpu)); - put_cpu_var(rcu_data); - put_cpu_var(rcu_bh_data); - tasklet_kill_immediate(&per_cpu(rcu_tasklet, cpu), cpu); -} - -#else - -static void rcu_offline_cpu(int cpu) -{ -} - -#endif - -/* - * This does the RCU processing work from tasklet context. - */ -static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp, - struct rcu_data *rdp) -{ - if (rdp->curlist && !rcu_batch_before(rcp->completed, rdp->batch)) { - *rdp->donetail = rdp->curlist; - rdp->donetail = rdp->curtail; - rdp->curlist = NULL; - rdp->curtail = &rdp->curlist; - } - - if (rdp->nxtlist && !rdp->curlist) { - local_irq_disable(); - rdp->curlist = rdp->nxtlist; - rdp->curtail = rdp->nxttail; - rdp->nxtlist = NULL; - rdp->nxttail = &rdp->nxtlist; - local_irq_enable(); - - /* - * start the next batch of callbacks - */ - - /* determine batch number */ - rdp->batch = rcp->cur + 1; - /* see the comment and corresponding wmb() in - * the rcu_start_batch() - */ - smp_rmb(); - - if (!rcp->next_pending) { - /* and start it/schedule start if it's a new batch */ - spin_lock(&rcp->lock); - rcp->next_pending = 1; - rcu_start_batch(rcp); - spin_unlock(&rcp->lock); - } - } - - rcu_check_quiescent_state(rcp, rdp); - if (rdp->donelist) - rcu_do_batch(rdp); -} - -static void rcu_process_callbacks(unsigned long unused) -{ - __rcu_process_callbacks(&rcu_ctrlblk, &__get_cpu_var(rcu_data)); - __rcu_process_callbacks(&rcu_bh_ctrlblk, &__get_cpu_var(rcu_bh_data)); -} - -static int __rcu_pending(struct rcu_ctrlblk *rcp, struct rcu_data *rdp) -{ - /* This cpu has pending rcu entries and the grace period - * for them has completed. - */ - if (rdp->curlist && !rcu_batch_before(rcp->completed, rdp->batch)) - return 1; - - /* This cpu has no pending entries, but there are new entries */ - if (!rdp->curlist && rdp->nxtlist) - return 1; - - /* This cpu has finished callbacks to invoke */ - if (rdp->donelist) - return 1; - - /* The rcu core waits for a quiescent state from the cpu */ - if (rdp->quiescbatch != rcp->cur || rdp->qs_pending) - return 1; - - /* nothing to do */ - return 0; -} - -/* - * Check to see if there is any immediate RCU-related work to be done - * by the current CPU, returning 1 if so. This function is part of the - * RCU implementation; it is -not- an exported member of the RCU API. - */ -int rcu_pending(int cpu) -{ - return __rcu_pending(&rcu_ctrlblk, &per_cpu(rcu_data, cpu)) || - __rcu_pending(&rcu_bh_ctrlblk, &per_cpu(rcu_bh_data, cpu)); -} - -/* - * Check to see if any future RCU-related work will need to be done - * by the current CPU, even if none need be done immediately, returning - * 1 if so. This function is part of the RCU implementation; it is -not- - * an exported member of the RCU API. - */ -int rcu_needs_cpu(int cpu) -{ - struct rcu_data *rdp = &per_cpu(rcu_data, cpu); - struct rcu_data *rdp_bh = &per_cpu(rcu_bh_data, cpu); - - return (!!rdp->curlist || !!rdp_bh->curlist || rcu_pending(cpu)); -} - -void rcu_check_callbacks(int cpu, int user) -{ - if (user || - (idle_cpu(cpu) && !in_softirq() && - hardirq_count() <= (1 << HARDIRQ_SHIFT))) { - rcu_qsctr_inc(cpu); - rcu_bh_qsctr_inc(cpu); - } else if (!in_softirq()) - rcu_bh_qsctr_inc(cpu); - tasklet_schedule(&per_cpu(rcu_tasklet, cpu)); -} - -static void rcu_init_percpu_data(int cpu, struct rcu_ctrlblk *rcp, - struct rcu_data *rdp) -{ - memset(rdp, 0, sizeof(*rdp)); - rdp->curtail = &rdp->curlist; - rdp->nxttail = &rdp->nxtlist; - rdp->donetail = &rdp->donelist; - rdp->quiescbatch = rcp->completed; - rdp->qs_pending = 0; - rdp->cpu = cpu; - rdp->blimit = blimit; -} - -static void __devinit rcu_online_cpu(int cpu) -{ - struct rcu_data *rdp = &per_cpu(rcu_data, cpu); - struct rcu_data *bh_rdp = &per_cpu(rcu_bh_data, cpu); - - rcu_init_percpu_data(cpu, &rcu_ctrlblk, rdp); - rcu_init_percpu_data(cpu, &rcu_bh_ctrlblk, bh_rdp); - tasklet_init(&per_cpu(rcu_tasklet, cpu), rcu_process_callbacks, 0UL); -} - -static int __cpuinit rcu_cpu_notify(struct notifier_block *self, - unsigned long action, void *hcpu) -{ - long cpu = (long)hcpu; - switch (action) { - case CPU_UP_PREPARE: - case CPU_UP_PREPARE_FROZEN: - rcu_online_cpu(cpu); - break; - case CPU_DEAD: - case CPU_DEAD_FROZEN: - rcu_offline_cpu(cpu); - break; - default: - break; - } - return NOTIFY_OK; -} - -static struct notifier_block __cpuinitdata rcu_nb = { - .notifier_call = rcu_cpu_notify, -}; - -/* - * Initializes rcu mechanism. Assumed to be called early. - * That is before local timer(SMP) or jiffie timer (uniproc) is setup. - * Note that rcu_qsctr and friends are implicitly - * initialized due to the choice of ``0'' for RCU_CTR_INVALID. - */ void __init rcu_init(void) { - rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE, - (void *)(long)smp_processor_id()); - /* Register notifier for non-boot CPUs */ - register_cpu_notifier(&rcu_nb); -} - -struct rcu_synchronize { - struct rcu_head head; - struct completion completion; -}; - -/* Because of FASTCALL declaration of complete, we use this wrapper */ -static void wakeme_after_rcu(struct rcu_head *head) -{ - struct rcu_synchronize *rcu; - - rcu = container_of(head, struct rcu_synchronize, head); - complete(&rcu->completion); + __rcu_init(); } -/** - * synchronize_rcu - wait until a grace period has elapsed. - * - * Control will return to the caller some time after a full grace - * period has elapsed, in other words after all currently executing RCU - * read-side critical sections have completed. RCU read-side critical - * sections are delimited by rcu_read_lock() and rcu_read_unlock(), - * and may be nested. - * - * If your read-side code is not protected by rcu_read_lock(), do -not- - * use synchronize_rcu(). - */ -void synchronize_rcu(void) -{ - struct rcu_synchronize rcu; - - init_completion(&rcu.completion); - /* Will wake me after RCU finished */ - call_rcu(&rcu.head, wakeme_after_rcu); - - /* Wait for it */ - wait_for_completion(&rcu.completion); -} - -module_param(blimit, int, 0); -module_param(qhimark, int, 0); -module_param(qlowmark, int, 0); -EXPORT_SYMBOL_GPL(rcu_batches_completed); -EXPORT_SYMBOL_GPL(rcu_batches_completed_bh); -EXPORT_SYMBOL_GPL(call_rcu); -EXPORT_SYMBOL_GPL(call_rcu_bh); -EXPORT_SYMBOL_GPL(synchronize_rcu); diff --git a/kernel/rcupreempt.c b/kernel/rcupreempt.c new file mode 100644 index 00000000000..987cfb7ade8 --- /dev/null +++ b/kernel/rcupreempt.c @@ -0,0 +1,953 @@ +/* + * Read-Copy Update mechanism for mutual exclusion, realtime implementation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright IBM Corporation, 2006 + * + * Authors: Paul E. McKenney <paulmck@us.ibm.com> + * With thanks to Esben Nielsen, Bill Huey, and Ingo Molnar + * for pushing me away from locks and towards counters, and + * to Suparna Bhattacharya for pushing me completely away + * from atomic instructions on the read side. + * + * Papers: http://www.rdrop.com/users/paulmck/RCU + * + * Design Document: http://lwn.net/Articles/253651/ + * + * For detailed explanation of Read-Copy Update mechanism see - + * Documentation/RCU/ *.txt + * + */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/smp.h> +#include <linux/rcupdate.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <asm/atomic.h> +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/completion.h> +#include <linux/moduleparam.h> +#include <linux/percpu.h> +#include <linux/notifier.h> +#include <linux/rcupdate.h> +#include <linux/cpu.h> +#include <linux/random.h> +#include <linux/delay.h> +#include <linux/byteorder/swabb.h> +#include <linux/cpumask.h> +#include <linux/rcupreempt_trace.h> + +/* + * Macro that prevents the compiler from reordering accesses, but does + * absolutely -nothing- to prevent CPUs from reordering. This is used + * only to mediate communication between mainline code and hardware + * interrupt and NMI handlers. + */ +#define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x)) + +/* + * PREEMPT_RCU data structures. + */ + +/* + * GP_STAGES specifies the number of times the state machine has + * to go through the all the rcu_try_flip_states (see below) + * in a single Grace Period. + * + * GP in GP_STAGES stands for Grace Period ;) + */ +#define GP_STAGES 2 +struct rcu_data { + spinlock_t lock; /* Protect rcu_data fields. */ + long completed; /* Number of last completed batch. */ + int waitlistcount; + struct tasklet_struct rcu_tasklet; + struct rcu_head *nextlist; + struct rcu_head **nexttail; + struct rcu_head *waitlist[GP_STAGES]; + struct rcu_head **waittail[GP_STAGES]; + struct rcu_head *donelist; + struct rcu_head **donetail; + long rcu_flipctr[2]; +#ifdef CONFIG_RCU_TRACE + struct rcupreempt_trace trace; +#endif /* #ifdef CONFIG_RCU_TRACE */ +}; + +/* + * States for rcu_try_flip() and friends. + */ + +enum rcu_try_flip_states { + + /* + * Stay here if nothing is happening. Flip the counter if somthing + * starts happening. Denoted by "I" + */ + rcu_try_flip_idle_state, + + /* + * Wait here for all CPUs to notice that the counter has flipped. This + * prevents the old set of counters from ever being incremented once + * we leave this state, which in turn is necessary because we cannot + * test any individual counter for zero -- we can only check the sum. + * Denoted by "A". + */ + rcu_try_flip_waitack_state, + + /* + * Wait here for the sum of the old per-CPU counters to reach zero. + * Denoted by "Z". + */ + rcu_try_flip_waitzero_state, + + /* + * Wait here for each of the other CPUs to execute a memory barrier. + * This is necessary to ensure that these other CPUs really have + * completed executing their RCU read-side critical sections, despite + * their CPUs wildly reordering memory. Denoted by "M". + */ + rcu_try_flip_waitmb_state, +}; + +struct rcu_ctrlblk { + spinlock_t fliplock; /* Protect state-machine transitions. */ + long completed; /* Number of last completed batch. */ + enum rcu_try_flip_states rcu_try_flip_state; /* The current state of + the rcu state machine */ +}; + +static DEFINE_PER_CPU(struct rcu_data, rcu_data); +static struct rcu_ctrlblk rcu_ctrlblk = { + .fliplock = __SPIN_LOCK_UNLOCKED(rcu_ctrlblk.fliplock), + .completed = 0, + .rcu_try_flip_state = rcu_try_flip_idle_state, +}; + + +#ifdef CONFIG_RCU_TRACE +static char *rcu_try_flip_state_names[] = + { "idle", "waitack", "waitzero", "waitmb" }; +#endif /* #ifdef CONFIG_RCU_TRACE */ + +static cpumask_t rcu_cpu_online_map __read_mostly = CPU_MASK_NONE; + +/* + * Enum and per-CPU flag to determine when each CPU has seen + * the most recent counter flip. + */ + +enum rcu_flip_flag_values { + rcu_flip_seen, /* Steady/initial state, last flip seen. */ + /* Only GP detector can update. */ + rcu_flipped /* Flip just completed, need confirmation. */ + /* Only corresponding CPU can update. */ +}; +static DEFINE_PER_CPU_SHARED_ALIGNED(enum rcu_flip_flag_values, rcu_flip_flag) + = rcu_flip_seen; + +/* + * Enum and per-CPU flag to determine when each CPU has executed the + * needed memory barrier to fence in memory references from its last RCU + * read-side critical section in the just-completed grace period. + */ + +enum rcu_mb_flag_values { + rcu_mb_done, /* Steady/initial state, no mb()s required. */ + /* Only GP detector can update. */ + rcu_mb_needed /* Flip just completed, need an mb(). */ + /* Only corresponding CPU can update. */ +}; +static DEFINE_PER_CPU_SHARED_ALIGNED(enum rcu_mb_flag_values, rcu_mb_flag) + = rcu_mb_done; + +/* + * RCU_DATA_ME: find the current CPU's rcu_data structure. + * RCU_DATA_CPU: find the specified CPU's rcu_data structure. + */ +#define RCU_DATA_ME() (&__get_cpu_var(rcu_data)) +#define RCU_DATA_CPU(cpu) (&per_cpu(rcu_data, cpu)) + +/* + * Helper macro for tracing when the appropriate rcu_data is not + * cached in a local variable, but where the CPU number is so cached. + */ +#define RCU_TRACE_CPU(f, cpu) RCU_TRACE(f, &(RCU_DATA_CPU(cpu)->trace)); + +/* + * Helper macro for tracing when the appropriate rcu_data is not + * cached in a local variable. + */ +#define RCU_TRACE_ME(f) RCU_TRACE(f, &(RCU_DATA_ME()->trace)); + +/* + * Helper macro for tracing when the appropriate rcu_data is pointed + * to by a local variable. + */ +#define RCU_TRACE_RDP(f, rdp) RCU_TRACE(f, &((rdp)->trace)); + +/* + * Return the number of RCU batches processed thus far. Useful + * for debug and statistics. + */ +long rcu_batches_completed(void) +{ + return rcu_ctrlblk.completed; +} +EXPORT_SYMBOL_GPL(rcu_batches_completed); + +EXPORT_SYMBOL_GPL(rcu_batches_completed_bh); + +void __rcu_read_lock(void) +{ + int idx; + struct task_struct *t = current; + int nesting; + + nesting = ACCESS_ONCE(t->rcu_read_lock_nesting); + if (nesting != 0) { + + /* An earlier rcu_read_lock() covers us, just count it. */ + + t->rcu_read_lock_nesting = nesting + 1; + + } else { + unsigned long flags; + + /* + * We disable interrupts for the following reasons: + * - If we get scheduling clock interrupt here, and we + * end up acking the counter flip, it's like a promise + * that we will never increment the old counter again. + * Thus we will break that promise if that + * scheduling clock interrupt happens between the time + * we pick the .completed field and the time that we + * increment our counter. + * + * - We don't want to be preempted out here. + * + * NMIs can still occur, of course, and might themselves + * contain rcu_read_lock(). + */ + + local_irq_save(flags); + + /* + * Outermost nesting of rcu_read_lock(), so increment + * the current counter for the current CPU. Use volatile + * casts to prevent the compiler from reordering. + */ + + idx = ACCESS_ONCE(rcu_ctrlblk.completed) & 0x1; + ACCESS_ONCE(RCU_DATA_ME()->rcu_flipctr[idx])++; + + /* + * Now that the per-CPU counter has been incremented, we + * are protected from races with rcu_read_lock() invoked + * from NMI handlers on this CPU. We can therefore safely + * increment the nesting counter, relieving further NMIs + * of the need to increment the per-CPU counter. + */ + + ACCESS_ONCE(t->rcu_read_lock_nesting) = nesting + 1; + + /* + * Now that we have preventing any NMIs from storing + * to the ->rcu_flipctr_idx, we can safely use it to + * remember which counter to decrement in the matching + * rcu_read_unlock(). + */ + + ACCESS_ONCE(t->rcu_flipctr_idx) = idx; + local_irq_restore(flags); + } +} +EXPORT_SYMBOL_GPL(__rcu_read_lock); + +void __rcu_read_unlock(void) +{ + int idx; + struct task_struct *t = current; + int nesting; + + nesting = ACCESS_ONCE(t->rcu_read_lock_nesting); + if (nesting > 1) { + + /* + * We are still protected by the enclosing rcu_read_lock(), + * so simply decrement the counter. + */ + + t->rcu_read_lock_nesting = nesting - 1; + + } else { + unsigned long flags; + + /* + * Disable local interrupts to prevent the grace-period + * detection state machine from seeing us half-done. + * NMIs can still occur, of course, and might themselves + * contain rcu_read_lock() and rcu_read_unlock(). + */ + + local_irq_save(flags); + + /* + * Outermost nesting of rcu_read_unlock(), so we must + * decrement the current counter for the current CPU. + * This must be done carefully, because NMIs can + * occur at any point in this code, and any rcu_read_lock() + * and rcu_read_unlock() pairs in the NMI handlers + * must interact non-destructively with this code. + * Lots of volatile casts, and -very- careful ordering. + * + * Changes to this code, including this one, must be + * inspected, validated, and tested extremely carefully!!! + */ + + /* + * First, pick up the index. + */ + + idx = ACCESS_ONCE(t->rcu_flipctr_idx); + + /* + * Now that we have fetched the counter index, it is + * safe to decrement the per-task RCU nesting counter. + * After this, any interrupts or NMIs will increment and + * decrement the per-CPU counters. + */ + ACCESS_ONCE(t->rcu_read_lock_nesting) = nesting - 1; + + /* + * It is now safe to decrement this task's nesting count. + * NMIs that occur after this statement will route their + * rcu_read_lock() calls through this "else" clause, and + * will thus start incrementing the per-CPU counter on + * their own. They will also clobber ->rcu_flipctr_idx, + * but that is OK, since we have already fetched it. + */ + + ACCESS_ONCE(RCU_DATA_ME()->rcu_flipctr[idx])--; + local_irq_restore(flags); + } +} +EXPORT_SYMBOL_GPL(__rcu_read_unlock); + +/* + * If a global counter flip has occurred since the last time that we + * advanced callbacks, advance them. Hardware interrupts must be + * disabled when calling this function. + */ +static void __rcu_advance_callbacks(struct rcu_data *rdp) +{ + int cpu; + int i; + int wlc = 0; + + if (rdp->completed != rcu_ctrlblk.completed) { + if (rdp->waitlist[GP_STAGES - 1] != NULL) { + *rdp->donetail = rdp->waitlist[GP_STAGES - 1]; + rdp->donetail = rdp->waittail[GP_STAGES - 1]; + RCU_TRACE_RDP(rcupreempt_trace_move2done, rdp); + } + for (i = GP_STAGES - 2; i >= 0; i--) { + if (rdp->waitlist[i] != NULL) { + rdp->waitlist[i + 1] = rdp->waitlist[i]; + rdp->waittail[i + 1] = rdp->waittail[i]; + wlc++; + } else { + rdp->waitlist[i + 1] = NULL; + rdp->waittail[i + 1] = + &rdp->waitlist[i + 1]; + } + } + if (rdp->nextlist != NULL) { + rdp->waitlist[0] = rdp->nextlist; + rdp->waittail[0] = rdp->nexttail; + wlc++; + rdp->nextlist = NULL; + rdp->nexttail = &rdp->nextlist; + RCU_TRACE_RDP(rcupreempt_trace_move2wait, rdp); + } else { + rdp->waitlist[0] = NULL; + rdp->waittail[0] = &rdp->waitlist[0]; + } + rdp->waitlistcount = wlc; + rdp->completed = rcu_ctrlblk.completed; + } + + /* + * Check to see if this CPU needs to report that it has seen + * the most recent counter flip, thereby declaring that all + * subsequent rcu_read_lock() invocations will respect this flip. + */ + + cpu = raw_smp_processor_id(); + if (per_cpu(rcu_flip_flag, cpu) == rcu_flipped) { + smp_mb(); /* Subsequent counter accesses must see new value */ + per_cpu(rcu_flip_flag, cpu) = rcu_flip_seen; + smp_mb(); /* Subsequent RCU read-side critical sections */ + /* seen -after- acknowledgement. */ + } +} + +/* + * Get here when RCU is idle. Decide whether we need to + * move out of idle state, and return non-zero if so. + * "Straightforward" approach for the moment, might later + * use callback-list lengths, grace-period duration, or + * some such to determine when to exit idle state. + * Might also need a pre-idle test that does not acquire + * the lock, but let's get the simple case working first... + */ + +static int +rcu_try_flip_idle(void) +{ + int cpu; + + RCU_TRACE_ME(rcupreempt_trace_try_flip_i1); + if (!rcu_pending(smp_processor_id())) { + RCU_TRACE_ME(rcupreempt_trace_try_flip_ie1); + return 0; + } + + /* + * Do the flip. + */ + + RCU_TRACE_ME(rcupreempt_trace_try_flip_g1); + rcu_ctrlblk.completed++; /* stands in for rcu_try_flip_g2 */ + + /* + * Need a memory barrier so that other CPUs see the new + * counter value before they see the subsequent change of all + * the rcu_flip_flag instances to rcu_flipped. + */ + + smp_mb(); /* see above block comment. */ + + /* Now ask each CPU for acknowledgement of the flip. */ + + for_each_cpu_mask(cpu, rcu_cpu_online_map) + per_cpu(rcu_flip_flag, cpu) = rcu_flipped; + + return 1; +} + +/* + * Wait for CPUs to acknowledge the flip. + */ + +static int +rcu_try_flip_waitack(void) +{ + int cpu; + + RCU_TRACE_ME(rcupreempt_trace_try_flip_a1); + for_each_cpu_mask(cpu, rcu_cpu_online_map) + if (per_cpu(rcu_flip_flag, cpu) != rcu_flip_seen) { + RCU_TRACE_ME(rcupreempt_trace_try_flip_ae1); + return 0; + } + + /* + * Make sure our checks above don't bleed into subsequent + * waiting for the sum of the counters to reach zero. + */ + + smp_mb(); /* see above block comment. */ + RCU_TRACE_ME(rcupreempt_trace_try_flip_a2); + return 1; +} + +/* + * Wait for collective ``last'' counter to reach zero, + * then tell all CPUs to do an end-of-grace-period memory barrier. + */ + +static int +rcu_try_flip_waitzero(void) +{ + int cpu; + int lastidx = !(rcu_ctrlblk.completed & 0x1); + int sum = 0; + + /* Check to see if the sum of the "last" counters is zero. */ + + RCU_TRACE_ME(rcupreempt_trace_try_flip_z1); + for_each_cpu_mask(cpu, rcu_cpu_online_map) + sum += RCU_DATA_CPU(cpu)->rcu_flipctr[lastidx]; + if (sum != 0) { + RCU_TRACE_ME(rcupreempt_trace_try_flip_ze1); + return 0; + } + + /* + * This ensures that the other CPUs see the call for + * memory barriers -after- the sum to zero has been + * detected here + */ + smp_mb(); /* ^^^^^^^^^^^^ */ + + /* Call for a memory barrier from each CPU. */ + for_each_cpu_mask(cpu, rcu_cpu_online_map) + per_cpu(rcu_mb_flag, cpu) = rcu_mb_needed; + + RCU_TRACE_ME(rcupreempt_trace_try_flip_z2); + return 1; +} + +/* + * Wait for all CPUs to do their end-of-grace-period memory barrier. + * Return 0 once all CPUs have done so. + */ + +static int +rcu_try_flip_waitmb(void) +{ + int cpu; + + RCU_TRACE_ME(rcupreempt_trace_try_flip_m1); + for_each_cpu_mask(cpu, rcu_cpu_online_map) + if (per_cpu(rcu_mb_flag, cpu) != rcu_mb_done) { + RCU_TRACE_ME(rcupreempt_trace_try_flip_me1); + return 0; + } + + smp_mb(); /* Ensure that the above checks precede any following flip. */ + RCU_TRACE_ME(rcupreempt_trace_try_flip_m2); + return 1; +} + +/* + * Attempt a single flip of the counters. Remember, a single flip does + * -not- constitute a grace period. Instead, the interval between + * at least GP_STAGES consecutive flips is a grace period. + * + * If anyone is nuts enough to run this CONFIG_PREEMPT_RCU implementation + * on a large SMP, they might want to use a hierarchical organization of + * the per-CPU-counter pairs. + */ +static void rcu_try_flip(void) +{ + unsigned long flags; + + RCU_TRACE_ME(rcupreempt_trace_try_flip_1); + if (unlikely(!spin_trylock_irqsave(&rcu_ctrlblk.fliplock, flags))) { + RCU_TRACE_ME(rcupreempt_trace_try_flip_e1); + return; + } + + /* + * Take the next transition(s) through the RCU grace-period + * flip-counter state machine. + */ + + switch (rcu_ctrlblk.rcu_try_flip_state) { + case rcu_try_flip_idle_state: + if (rcu_try_flip_idle()) + rcu_ctrlblk.rcu_try_flip_state = + rcu_try_flip_waitack_state; + break; + case rcu_try_flip_waitack_state: + if (rcu_try_flip_waitack()) + rcu_ctrlblk.rcu_try_flip_state = + rcu_try_flip_waitzero_state; + break; + case rcu_try_flip_waitzero_state: + if (rcu_try_flip_waitzero()) + rcu_ctrlblk.rcu_try_flip_state = + rcu_try_flip_waitmb_state; + break; + case rcu_try_flip_waitmb_state: + if (rcu_try_flip_waitmb()) + rcu_ctrlblk.rcu_try_flip_state = + rcu_try_flip_idle_state; + } + spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags); +} + +/* + * Check to see if this CPU needs to do a memory barrier in order to + * ensure that any prior RCU read-side critical sections have committed + * their counter manipulations and critical-section memory references + * before declaring the grace period to be completed. + */ +static void rcu_check_mb(int cpu) +{ + if (per_cpu(rcu_mb_flag, cpu) == rcu_mb_needed) { + smp_mb(); /* Ensure RCU read-side accesses are visible. */ + per_cpu(rcu_mb_flag, cpu) = rcu_mb_done; + } +} + +void rcu_check_callbacks(int cpu, int user) +{ + unsigned long flags; + struct rcu_data *rdp = RCU_DATA_CPU(cpu); + + rcu_check_mb(cpu); + if (rcu_ctrlblk.completed == rdp->completed) + rcu_try_flip(); + spin_lock_irqsave(&rdp->lock, flags); + RCU_TRACE_RDP(rcupreempt_trace_check_callbacks, rdp); + __rcu_advance_callbacks(rdp); + if (rdp->donelist == NULL) { + spin_unlock_irqrestore(&rdp->lock, flags); + } else { + spin_unlock_irqrestore(&rdp->lock, flags); + raise_softirq(RCU_SOFTIRQ); + } +} + +/* + * Needed by dynticks, to make sure all RCU processing has finished + * when we go idle: + */ +void rcu_advance_callbacks(int cpu, int user) +{ + unsigned long flags; + struct rcu_data *rdp = RCU_DATA_CPU(cpu); + + if (rcu_ctrlblk.completed == rdp->completed) { + rcu_try_flip(); + if (rcu_ctrlblk.completed == rdp->completed) + return; + } + spin_lock_irqsave(&rdp->lock, flags); + RCU_TRACE_RDP(rcupreempt_trace_check_callbacks, rdp); + __rcu_advance_callbacks(rdp); + spin_unlock_irqrestore(&rdp->lock, flags); +} + +#ifdef CONFIG_HOTPLUG_CPU +#define rcu_offline_cpu_enqueue(srclist, srctail, dstlist, dsttail) do { \ + *dsttail = srclist; \ + if (srclist != NULL) { \ + dsttail = srctail; \ + srclist = NULL; \ + srctail = &srclist;\ + } \ + } while (0) + +void rcu_offline_cpu(int cpu) +{ + int i; + struct rcu_head *list = NULL; + unsigned long flags; + struct rcu_data *rdp = RCU_DATA_CPU(cpu); + struct rcu_head **tail = &list; + + /* + * Remove all callbacks from the newly dead CPU, retaining order. + * Otherwise rcu_barrier() will fail + */ + + spin_lock_irqsave(&rdp->lock, flags); + rcu_offline_cpu_enqueue(rdp->donelist, rdp->donetail, list, tail); + for (i = GP_STAGES - 1; i >= 0; i--) + rcu_offline_cpu_enqueue(rdp->waitlist[i], rdp->waittail[i], + list, tail); + rcu_offline_cpu_enqueue(rdp->nextlist, rdp->nexttail, list, tail); + spin_unlock_irqrestore(&rdp->lock, flags); + rdp->waitlistcount = 0; + + /* Disengage the newly dead CPU from the grace-period computation. */ + + spin_lock_irqsave(&rcu_ctrlblk.fliplock, flags); + rcu_check_mb(cpu); + if (per_cpu(rcu_flip_flag, cpu) == rcu_flipped) { + smp_mb(); /* Subsequent counter accesses must see new value */ + per_cpu(rcu_flip_flag, cpu) = rcu_flip_seen; + smp_mb(); /* Subsequent RCU read-side critical sections */ + /* seen -after- acknowledgement. */ + } + + RCU_DATA_ME()->rcu_flipctr[0] += RCU_DATA_CPU(cpu)->rcu_flipctr[0]; + RCU_DATA_ME()->rcu_flipctr[1] += RCU_DATA_CPU(cpu)->rcu_flipctr[1]; + + RCU_DATA_CPU(cpu)->rcu_flipctr[0] = 0; + RCU_DATA_CPU(cpu)->rcu_flipctr[1] = 0; + + cpu_clear(cpu, rcu_cpu_online_map); + + spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags); + + /* + * Place the removed callbacks on the current CPU's queue. + * Make them all start a new grace period: simple approach, + * in theory could starve a given set of callbacks, but + * you would need to be doing some serious CPU hotplugging + * to make this happen. If this becomes a problem, adding + * a synchronize_rcu() to the hotplug path would be a simple + * fix. + */ + + rdp = RCU_DATA_ME(); + spin_lock_irqsave(&rdp->lock, flags); + *rdp->nexttail = list; + if (list) + rdp->nexttail = tail; + spin_unlock_irqrestore(&rdp->lock, flags); +} + +void __devinit rcu_online_cpu(int cpu) +{ + unsigned long flags; + + spin_lock_irqsave(&rcu_ctrlblk.fliplock, flags); + cpu_set(cpu, rcu_cpu_online_map); + spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags); +} + +#else /* #ifdef CONFIG_HOTPLUG_CPU */ + +void rcu_offline_cpu(int cpu) +{ +} + +void __devinit rcu_online_cpu(int cpu) +{ +} + +#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */ + +static void rcu_process_callbacks(struct softirq_action *unused) +{ + unsigned long flags; + struct rcu_head *next, *list; + struct rcu_data *rdp = RCU_DATA_ME(); + + spin_lock_irqsave(&rdp->lock, flags); + list = rdp->donelist; + if (list == NULL) { + spin_unlock_irqrestore(&rdp->lock, flags); + return; + } + rdp->donelist = NULL; + rdp->donetail = &rdp->donelist; + RCU_TRACE_RDP(rcupreempt_trace_done_remove, rdp); + spin_unlock_irqrestore(&rdp->lock, flags); + while (list) { + next = list->next; + list->func(list); + list = next; + RCU_TRACE_ME(rcupreempt_trace_invoke); + } +} + +void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +{ + unsigned long flags; + struct rcu_data *rdp; + + head->func = func; + head->next = NULL; + local_irq_save(flags); + rdp = RCU_DATA_ME(); + spin_lock(&rdp->lock); + __rcu_advance_callbacks(rdp); + *rdp->nexttail = head; + rdp->nexttail = &head->next; + RCU_TRACE_RDP(rcupreempt_trace_next_add, rdp); + spin_unlock(&rdp->lock); + local_irq_restore(flags); +} +EXPORT_SYMBOL_GPL(call_rcu); + +/* + * Wait until all currently running preempt_disable() code segments + * (including hardware-irq-disable segments) complete. Note that + * in -rt this does -not- necessarily result in all currently executing + * interrupt -handlers- having completed. + */ +void __synchronize_sched(void) +{ + cpumask_t oldmask; + int cpu; + + if (sched_getaffinity(0, &oldmask) < 0) + oldmask = cpu_possible_map; + for_each_online_cpu(cpu) { + sched_setaffinity(0, cpumask_of_cpu(cpu)); + schedule(); + } + sched_setaffinity(0, oldmask); +} +EXPORT_SYMBOL_GPL(__synchronize_sched); + +/* + * Check to see if any future RCU-related work will need to be done + * by the current CPU, even if none need be done immediately, returning + * 1 if so. Assumes that notifiers would take care of handling any + * outstanding requests from the RCU core. + * + * This function is part of the RCU implementation; it is -not- + * an exported member of the RCU API. + */ +int rcu_needs_cpu(int cpu) +{ + struct rcu_data *rdp = RCU_DATA_CPU(cpu); + + return (rdp->donelist != NULL || + !!rdp->waitlistcount || + rdp->nextlist != NULL); +} + +int rcu_pending(int cpu) +{ + struct rcu_data *rdp = RCU_DATA_CPU(cpu); + + /* The CPU has at least one callback queued somewhere. */ + + if (rdp->donelist != NULL || + !!rdp->waitlistcount || + rdp->nextlist != NULL) + return 1; + + /* The RCU core needs an acknowledgement from this CPU. */ + + if ((per_cpu(rcu_flip_flag, cpu) == rcu_flipped) || + (per_cpu(rcu_mb_flag, cpu) == rcu_mb_needed)) + return 1; + + /* This CPU has fallen behind the global grace-period number. */ + + if (rdp->completed != rcu_ctrlblk.completed) + return 1; + + /* Nothing needed from this CPU. */ + + return 0; +} + +static int __cpuinit rcu_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + long cpu = (long)hcpu; + + switch (action) { + case CPU_UP_PREPARE: + case CPU_UP_PREPARE_FROZEN: + rcu_online_cpu(cpu); + break; + case CPU_UP_CANCELED: + case CPU_UP_CANCELED_FROZEN: + case CPU_DEAD: + case CPU_DEAD_FROZEN: + rcu_offline_cpu(cpu); + break; + default: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata rcu_nb = { + .notifier_call = rcu_cpu_notify, +}; + +void __init __rcu_init(void) +{ + int cpu; + int i; + struct rcu_data *rdp; + + printk(KERN_NOTICE "Preemptible RCU implementation.\n"); + for_each_possible_cpu(cpu) { + rdp = RCU_DATA_CPU(cpu); + spin_lock_init(&rdp->lock); + rdp->completed = 0; + rdp->waitlistcount = 0; + rdp->nextlist = NULL; + rdp->nexttail = &rdp->nextlist; + for (i = 0; i < GP_STAGES; i++) { + rdp->waitlist[i] = NULL; + rdp->waittail[i] = &rdp->waitlist[i]; + } + rdp->donelist = NULL; + rdp->donetail = &rdp->donelist; + rdp->rcu_flipctr[0] = 0; + rdp->rcu_flipctr[1] = 0; + } + register_cpu_notifier(&rcu_nb); + + /* + * We don't need protection against CPU-Hotplug here + * since + * a) If a CPU comes online while we are iterating over the + * cpu_online_map below, we would only end up making a + * duplicate call to rcu_online_cpu() which sets the corresponding + * CPU's mask in the rcu_cpu_online_map. + * + * b) A CPU cannot go offline at this point in time since the user + * does not have access to the sysfs interface, nor do we + * suspend the system. + */ + for_each_online_cpu(cpu) + rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE, (void *)(long) cpu); + + open_softirq(RCU_SOFTIRQ, rcu_process_callbacks, NULL); +} + +/* + * Deprecated, use synchronize_rcu() or synchronize_sched() instead. + */ +void synchronize_kernel(void) +{ + synchronize_rcu(); +} + +#ifdef CONFIG_RCU_TRACE +long *rcupreempt_flipctr(int cpu) +{ + return &RCU_DATA_CPU(cpu)->rcu_flipctr[0]; +} +EXPORT_SYMBOL_GPL(rcupreempt_flipctr); + +int rcupreempt_flip_flag(int cpu) +{ + return per_cpu(rcu_flip_flag, cpu); +} +EXPORT_SYMBOL_GPL(rcupreempt_flip_flag); + +int rcupreempt_mb_flag(int cpu) +{ + return per_cpu(rcu_mb_flag, cpu); +} +EXPORT_SYMBOL_GPL(rcupreempt_mb_flag); + +char *rcupreempt_try_flip_state_name(void) +{ + return rcu_try_flip_state_names[rcu_ctrlblk.rcu_try_flip_state]; +} +EXPORT_SYMBOL_GPL(rcupreempt_try_flip_state_name); + +struct rcupreempt_trace *rcupreempt_trace_cpu(int cpu) +{ + struct rcu_data *rdp = RCU_DATA_CPU(cpu); + + return &rdp->trace; +} +EXPORT_SYMBOL_GPL(rcupreempt_trace_cpu); + +#endif /* #ifdef RCU_TRACE */ diff --git a/kernel/rcupreempt_trace.c b/kernel/rcupreempt_trace.c new file mode 100644 index 00000000000..49ac4947af2 --- /dev/null +++ b/kernel/rcupreempt_trace.c @@ -0,0 +1,330 @@ +/* + * Read-Copy Update tracing for realtime implementation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Copyright IBM Corporation, 2006 + * + * Papers: http://www.rdrop.com/users/paulmck/RCU + * + * For detailed explanation of Read-Copy Update mechanism see - + * Documentation/RCU/ *.txt + * + */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/smp.h> +#include <linux/rcupdate.h> +#include <linux/interrupt.h> +#include <linux/sched.h> +#include <asm/atomic.h> +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/completion.h> +#include <linux/moduleparam.h> +#include <linux/percpu.h> +#include <linux/notifier.h> +#include <linux/rcupdate.h> +#include <linux/cpu.h> +#include <linux/mutex.h> +#include <linux/rcupreempt_trace.h> +#include <linux/debugfs.h> + +static struct mutex rcupreempt_trace_mutex; +static char *rcupreempt_trace_buf; +#define RCUPREEMPT_TRACE_BUF_SIZE 4096 + +void rcupreempt_trace_move2done(struct rcupreempt_trace *trace) +{ + trace->done_length += trace->wait_length; + trace->done_add += trace->wait_length; + trace->wait_length = 0; +} +void rcupreempt_trace_move2wait(struct rcupreempt_trace *trace) +{ + trace->wait_length += trace->next_length; + trace->wait_add += trace->next_length; + trace->next_length = 0; +} +void rcupreempt_trace_try_flip_1(struct rcupreempt_trace *trace) +{ + atomic_inc(&trace->rcu_try_flip_1); +} +void rcupreempt_trace_try_flip_e1(struct rcupreempt_trace *trace) +{ + atomic_inc(&trace->rcu_try_flip_e1); +} +void rcupreempt_trace_try_flip_i1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_i1++; +} +void rcupreempt_trace_try_flip_ie1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_ie1++; +} +void rcupreempt_trace_try_flip_g1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_g1++; +} +void rcupreempt_trace_try_flip_a1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_a1++; +} +void rcupreempt_trace_try_flip_ae1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_ae1++; +} +void rcupreempt_trace_try_flip_a2(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_a2++; +} +void rcupreempt_trace_try_flip_z1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_z1++; +} +void rcupreempt_trace_try_flip_ze1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_ze1++; +} +void rcupreempt_trace_try_flip_z2(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_z2++; +} +void rcupreempt_trace_try_flip_m1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_m1++; +} +void rcupreempt_trace_try_flip_me1(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_me1++; +} +void rcupreempt_trace_try_flip_m2(struct rcupreempt_trace *trace) +{ + trace->rcu_try_flip_m2++; +} +void rcupreempt_trace_check_callbacks(struct rcupreempt_trace *trace) +{ + trace->rcu_check_callbacks++; +} +void rcupreempt_trace_done_remove(struct rcupreempt_trace *trace) +{ + trace->done_remove += trace->done_length; + trace->done_length = 0; +} +void rcupreempt_trace_invoke(struct rcupreempt_trace *trace) +{ + atomic_inc(&trace->done_invoked); +} +void rcupreempt_trace_next_add(struct rcupreempt_trace *trace) +{ + trace->next_add++; + trace->next_length++; +} + +static void rcupreempt_trace_sum(struct rcupreempt_trace *sp) +{ + struct rcupreempt_trace *cp; + int cpu; + + memset(sp, 0, sizeof(*sp)); + for_each_possible_cpu(cpu) { + cp = rcupreempt_trace_cpu(cpu); + sp->next_length += cp->next_length; + sp->next_add += cp->next_add; + sp->wait_length += cp->wait_length; + sp->wait_add += cp->wait_add; + sp->done_length += cp->done_length; + sp->done_add += cp->done_add; + sp->done_remove += cp->done_remove; + atomic_set(&sp->done_invoked, atomic_read(&cp->done_invoked)); + sp->rcu_check_callbacks += cp->rcu_check_callbacks; + atomic_set(&sp->rcu_try_flip_1, + atomic_read(&cp->rcu_try_flip_1)); + atomic_set(&sp->rcu_try_flip_e1, + atomic_read(&cp->rcu_try_flip_e1)); + sp->rcu_try_flip_i1 += cp->rcu_try_flip_i1; + sp->rcu_try_flip_ie1 += cp->rcu_try_flip_ie1; + sp->rcu_try_flip_g1 += cp->rcu_try_flip_g1; + sp->rcu_try_flip_a1 += cp->rcu_try_flip_a1; + sp->rcu_try_flip_ae1 += cp->rcu_try_flip_ae1; + sp->rcu_try_flip_a2 += cp->rcu_try_flip_a2; + sp->rcu_try_flip_z1 += cp->rcu_try_flip_z1; + sp->rcu_try_flip_ze1 += cp->rcu_try_flip_ze1; + sp->rcu_try_flip_z2 += cp->rcu_try_flip_z2; + sp->rcu_try_flip_m1 += cp->rcu_try_flip_m1; + sp->rcu_try_flip_me1 += cp->rcu_try_flip_me1; + sp->rcu_try_flip_m2 += cp->rcu_try_flip_m2; + } +} + +static ssize_t rcustats_read(struct file *filp, char __user *buffer, + size_t count, loff_t *ppos) +{ + struct rcupreempt_trace trace; + ssize_t bcount; + int cnt = 0; + + rcupreempt_trace_sum(&trace); + mutex_lock(&rcupreempt_trace_mutex); + snprintf(&rcupreempt_trace_buf[cnt], RCUPREEMPT_TRACE_BUF_SIZE - cnt, + "ggp=%ld rcc=%ld\n", + rcu_batches_completed(), + trace.rcu_check_callbacks); + snprintf(&rcupreempt_trace_buf[cnt], RCUPREEMPT_TRACE_BUF_SIZE - cnt, + "na=%ld nl=%ld wa=%ld wl=%ld da=%ld dl=%ld dr=%ld di=%d\n" + "1=%d e1=%d i1=%ld ie1=%ld g1=%ld a1=%ld ae1=%ld a2=%ld\n" + "z1=%ld ze1=%ld z2=%ld m1=%ld me1=%ld m2=%ld\n", + + trace.next_add, trace.next_length, + trace.wait_add, trace.wait_length, + trace.done_add, trace.done_length, + trace.done_remove, atomic_read(&trace.done_invoked), + atomic_read(&trace.rcu_try_flip_1), + atomic_read(&trace.rcu_try_flip_e1), + trace.rcu_try_flip_i1, trace.rcu_try_flip_ie1, + trace.rcu_try_flip_g1, + trace.rcu_try_flip_a1, trace.rcu_try_flip_ae1, + trace.rcu_try_flip_a2, + trace.rcu_try_flip_z1, trace.rcu_try_flip_ze1, + trace.rcu_try_flip_z2, + trace.rcu_try_flip_m1, trace.rcu_try_flip_me1, + trace.rcu_try_flip_m2); + bcount = simple_read_from_buffer(buffer, count, ppos, + rcupreempt_trace_buf, strlen(rcupreempt_trace_buf)); + mutex_unlock(&rcupreempt_trace_mutex); + return bcount; +} + +static ssize_t rcugp_read(struct file *filp, char __user *buffer, + size_t count, loff_t *ppos) +{ + long oldgp = rcu_batches_completed(); + ssize_t bcount; + + mutex_lock(&rcupreempt_trace_mutex); + synchronize_rcu(); + snprintf(rcupreempt_trace_buf, RCUPREEMPT_TRACE_BUF_SIZE, + "oldggp=%ld newggp=%ld\n", oldgp, rcu_batches_completed()); + bcount = simple_read_from_buffer(buffer, count, ppos, + rcupreempt_trace_buf, strlen(rcupreempt_trace_buf)); + mutex_unlock(&rcupreempt_trace_mutex); + return bcount; +} + +static ssize_t rcuctrs_read(struct file *filp, char __user *buffer, + size_t count, loff_t *ppos) +{ + int cnt = 0; + int cpu; + int f = rcu_batches_completed() & 0x1; + ssize_t bcount; + + mutex_lock(&rcupreempt_trace_mutex); + + cnt += snprintf(&rcupreempt_trace_buf[cnt], RCUPREEMPT_TRACE_BUF_SIZE, + "CPU last cur F M\n"); + for_each_online_cpu(cpu) { + long *flipctr = rcupreempt_flipctr(cpu); + cnt += snprintf(&rcupreempt_trace_buf[cnt], + RCUPREEMPT_TRACE_BUF_SIZE - cnt, + "%3d %4ld %3ld %d %d\n", + cpu, + flipctr[!f], + flipctr[f], + rcupreempt_flip_flag(cpu), + rcupreempt_mb_flag(cpu)); + } + cnt += snprintf(&rcupreempt_trace_buf[cnt], + RCUPREEMPT_TRACE_BUF_SIZE - cnt, + "ggp = %ld, state = %s\n", + rcu_batches_completed(), + rcupreempt_try_flip_state_name()); + cnt += snprintf(&rcupreempt_trace_buf[cnt], + RCUPREEMPT_TRACE_BUF_SIZE - cnt, + "\n"); + bcount = simple_read_from_buffer(buffer, count, ppos, + rcupreempt_trace_buf, strlen(rcupreempt_trace_buf)); + mutex_unlock(&rcupreempt_trace_mutex); + return bcount; +} + +static struct file_operations rcustats_fops = { + .owner = THIS_MODULE, + .read = rcustats_read, +}; + +static struct file_operations rcugp_fops = { + .owner = THIS_MODULE, + .read = rcugp_read, +}; + +static struct file_operations rcuctrs_fops = { + .owner = THIS_MODULE, + .read = rcuctrs_read, +}; + +static struct dentry *rcudir, *statdir, *ctrsdir, *gpdir; +static int rcupreempt_debugfs_init(void) +{ + rcudir = debugfs_create_dir("rcu", NULL); + if (!rcudir) + goto out; + statdir = debugfs_create_file("rcustats", 0444, rcudir, + NULL, &rcustats_fops); + if (!statdir) + goto free_out; + + gpdir = debugfs_create_file("rcugp", 0444, rcudir, NULL, &rcugp_fops); + if (!gpdir) + goto free_out; + + ctrsdir = debugfs_create_file("rcuctrs", 0444, rcudir, + NULL, &rcuctrs_fops); + if (!ctrsdir) + goto free_out; + return 0; +free_out: + if (statdir) + debugfs_remove(statdir); + if (gpdir) + debugfs_remove(gpdir); + debugfs_remove(rcudir); +out: + return 1; +} + +static int __init rcupreempt_trace_init(void) +{ + mutex_init(&rcupreempt_trace_mutex); + rcupreempt_trace_buf = kmalloc(RCUPREEMPT_TRACE_BUF_SIZE, GFP_KERNEL); + if (!rcupreempt_trace_buf) + return 1; + return rcupreempt_debugfs_init(); +} + +static void __exit rcupreempt_trace_cleanup(void) +{ + debugfs_remove(statdir); + debugfs_remove(gpdir); + debugfs_remove(ctrsdir); + debugfs_remove(rcudir); + kfree(rcupreempt_trace_buf); +} + + +module_init(rcupreempt_trace_init); +module_exit(rcupreempt_trace_cleanup); diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index c3e165c2318..fd599829e72 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -726,11 +726,11 @@ static void rcu_torture_shuffle_tasks(void) cpumask_t tmp_mask = CPU_MASK_ALL; int i; - lock_cpu_hotplug(); + get_online_cpus(); /* No point in shuffling if there is only one online CPU (ex: UP) */ if (num_online_cpus() == 1) { - unlock_cpu_hotplug(); + put_online_cpus(); return; } @@ -762,7 +762,7 @@ static void rcu_torture_shuffle_tasks(void) else rcu_idle_cpu--; - unlock_cpu_hotplug(); + put_online_cpus(); } /* Shuffle tasks across CPUs, with the intent of allowing each CPU in the diff --git a/kernel/relay.c b/kernel/relay.c index 61134eb7a0c..d080b9d161a 100644 --- a/kernel/relay.c +++ b/kernel/relay.c @@ -37,37 +37,31 @@ static void relay_file_mmap_close(struct vm_area_struct *vma) } /* - * nopage() vm_op implementation for relay file mapping. + * fault() vm_op implementation for relay file mapping. */ -static struct page *relay_buf_nopage(struct vm_area_struct *vma, - unsigned long address, - int *type) +static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf) { struct page *page; struct rchan_buf *buf = vma->vm_private_data; - unsigned long offset = address - vma->vm_start; + pgoff_t pgoff = vmf->pgoff; - if (address > vma->vm_end) - return NOPAGE_SIGBUS; /* Disallow mremap */ if (!buf) - return NOPAGE_OOM; + return VM_FAULT_OOM; - page = vmalloc_to_page(buf->start + offset); + page = vmalloc_to_page(buf->start + (pgoff << PAGE_SHIFT)); if (!page) - return NOPAGE_OOM; + return VM_FAULT_SIGBUS; get_page(page); + vmf->page = page; - if (type) - *type = VM_FAULT_MINOR; - - return page; + return 0; } /* * vm_ops for relay file mappings. */ static struct vm_operations_struct relay_file_mmap_ops = { - .nopage = relay_buf_nopage, + .fault = relay_buf_fault, .close = relay_file_mmap_close, }; @@ -92,6 +86,7 @@ static int relay_mmap_buf(struct rchan_buf *buf, struct vm_area_struct *vma) return -EINVAL; vma->vm_ops = &relay_file_mmap_ops; + vma->vm_flags |= VM_DONTEXPAND; vma->vm_private_data = buf; buf->chan->cb->buf_mapped(buf, filp); diff --git a/kernel/rtmutex-tester.c b/kernel/rtmutex-tester.c index e3055ba6915..092e4c620af 100644 --- a/kernel/rtmutex-tester.c +++ b/kernel/rtmutex-tester.c @@ -394,7 +394,7 @@ static SYSDEV_ATTR(status, 0600, sysfs_test_status, NULL); static SYSDEV_ATTR(command, 0600, NULL, sysfs_test_command); static struct sysdev_class rttest_sysclass = { - set_kset_name("rttest"), + .name = "rttest", }; static int init_test_thread(int id) diff --git a/kernel/rwsem.c b/kernel/rwsem.c index 1ec620c0306..cae050b05f5 100644 --- a/kernel/rwsem.c +++ b/kernel/rwsem.c @@ -6,6 +6,7 @@ #include <linux/types.h> #include <linux/kernel.h> +#include <linux/sched.h> #include <linux/module.h> #include <linux/rwsem.h> @@ -15,7 +16,7 @@ /* * lock for reading */ -void down_read(struct rw_semaphore *sem) +void __sched down_read(struct rw_semaphore *sem) { might_sleep(); rwsem_acquire_read(&sem->dep_map, 0, 0, _RET_IP_); @@ -42,7 +43,7 @@ EXPORT_SYMBOL(down_read_trylock); /* * lock for writing */ -void down_write(struct rw_semaphore *sem) +void __sched down_write(struct rw_semaphore *sem) { might_sleep(); rwsem_acquire(&sem->dep_map, 0, 0, _RET_IP_); diff --git a/kernel/sched.c b/kernel/sched.c index c6e551de795..9474b23c28b 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -22,6 +22,8 @@ * by Peter Williams * 2007-05-06 Interactivity improvements to CFS by Mike Galbraith * 2007-07-01 Group scheduling enhancements by Srivatsa Vaddagiri + * 2007-11-29 RT balancing improvements by Steven Rostedt, Gregory Haskins, + * Thomas Gleixner, Mike Kravetz */ #include <linux/mm.h> @@ -63,6 +65,7 @@ #include <linux/reciprocal_div.h> #include <linux/unistd.h> #include <linux/pagemap.h> +#include <linux/hrtimer.h> #include <asm/tlb.h> #include <asm/irq_regs.h> @@ -96,10 +99,9 @@ unsigned long long __attribute__((weak)) sched_clock(void) #define MAX_USER_PRIO (USER_PRIO(MAX_PRIO)) /* - * Some helpers for converting nanosecond timing to jiffy resolution + * Helpers for converting nanosecond timing to jiffy resolution */ #define NS_TO_JIFFIES(TIME) ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ)) -#define JIFFIES_TO_NS(TIME) ((TIME) * (NSEC_PER_SEC / HZ)) #define NICE_0_LOAD SCHED_LOAD_SCALE #define NICE_0_SHIFT SCHED_LOAD_SHIFT @@ -159,6 +161,8 @@ struct rt_prio_array { struct cfs_rq; +static LIST_HEAD(task_groups); + /* task group related information */ struct task_group { #ifdef CONFIG_FAIR_CGROUP_SCHED @@ -168,10 +172,50 @@ struct task_group { struct sched_entity **se; /* runqueue "owned" by this group on each cpu */ struct cfs_rq **cfs_rq; + + struct sched_rt_entity **rt_se; + struct rt_rq **rt_rq; + + unsigned int rt_ratio; + + /* + * shares assigned to a task group governs how much of cpu bandwidth + * is allocated to the group. The more shares a group has, the more is + * the cpu bandwidth allocated to it. + * + * For ex, lets say that there are three task groups, A, B and C which + * have been assigned shares 1000, 2000 and 3000 respectively. Then, + * cpu bandwidth allocated by the scheduler to task groups A, B and C + * should be: + * + * Bw(A) = 1000/(1000+2000+3000) * 100 = 16.66% + * Bw(B) = 2000/(1000+2000+3000) * 100 = 33.33% + * Bw(C) = 3000/(1000+2000+3000) * 100 = 50% + * + * The weight assigned to a task group's schedulable entities on every + * cpu (task_group.se[a_cpu]->load.weight) is derived from the task + * group's shares. For ex: lets say that task group A has been + * assigned shares of 1000 and there are two CPUs in a system. Then, + * + * tg_A->se[0]->load.weight = tg_A->se[1]->load.weight = 1000; + * + * Note: It's not necessary that each of a task's group schedulable + * entity have the same weight on all CPUs. If the group + * has 2 of its tasks on CPU0 and 1 task on CPU1, then a + * better distribution of weight could be: + * + * tg_A->se[0]->load.weight = 2/3 * 2000 = 1333 + * tg_A->se[1]->load.weight = 1/2 * 2000 = 667 + * + * rebalance_shares() is responsible for distributing the shares of a + * task groups like this among the group's schedulable entities across + * cpus. + * + */ unsigned long shares; - /* spinlock to serialize modification to shares */ - spinlock_t lock; + struct rcu_head rcu; + struct list_head list; }; /* Default task group's sched entity on each cpu */ @@ -179,24 +223,51 @@ static DEFINE_PER_CPU(struct sched_entity, init_sched_entity); /* Default task group's cfs_rq on each cpu */ static DEFINE_PER_CPU(struct cfs_rq, init_cfs_rq) ____cacheline_aligned_in_smp; +static DEFINE_PER_CPU(struct sched_rt_entity, init_sched_rt_entity); +static DEFINE_PER_CPU(struct rt_rq, init_rt_rq) ____cacheline_aligned_in_smp; + static struct sched_entity *init_sched_entity_p[NR_CPUS]; static struct cfs_rq *init_cfs_rq_p[NR_CPUS]; +static struct sched_rt_entity *init_sched_rt_entity_p[NR_CPUS]; +static struct rt_rq *init_rt_rq_p[NR_CPUS]; + +/* task_group_mutex serializes add/remove of task groups and also changes to + * a task group's cpu shares. + */ +static DEFINE_MUTEX(task_group_mutex); + +/* doms_cur_mutex serializes access to doms_cur[] array */ +static DEFINE_MUTEX(doms_cur_mutex); + +#ifdef CONFIG_SMP +/* kernel thread that runs rebalance_shares() periodically */ +static struct task_struct *lb_monitor_task; +static int load_balance_monitor(void *unused); +#endif + +static void set_se_shares(struct sched_entity *se, unsigned long shares); + /* Default task group. * Every task in system belong to this group at bootup. */ struct task_group init_task_group = { - .se = init_sched_entity_p, + .se = init_sched_entity_p, .cfs_rq = init_cfs_rq_p, + + .rt_se = init_sched_rt_entity_p, + .rt_rq = init_rt_rq_p, }; #ifdef CONFIG_FAIR_USER_SCHED -# define INIT_TASK_GRP_LOAD 2*NICE_0_LOAD +# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD) #else -# define INIT_TASK_GRP_LOAD NICE_0_LOAD +# define INIT_TASK_GROUP_LOAD NICE_0_LOAD #endif -static int init_task_group_load = INIT_TASK_GRP_LOAD; +#define MIN_GROUP_SHARES 2 + +static int init_task_group_load = INIT_TASK_GROUP_LOAD; /* return group to which a task belongs */ static inline struct task_group *task_group(struct task_struct *p) @@ -215,15 +286,42 @@ static inline struct task_group *task_group(struct task_struct *p) } /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ -static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) +static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { p->se.cfs_rq = task_group(p)->cfs_rq[cpu]; p->se.parent = task_group(p)->se[cpu]; + + p->rt.rt_rq = task_group(p)->rt_rq[cpu]; + p->rt.parent = task_group(p)->rt_se[cpu]; +} + +static inline void lock_task_group_list(void) +{ + mutex_lock(&task_group_mutex); +} + +static inline void unlock_task_group_list(void) +{ + mutex_unlock(&task_group_mutex); +} + +static inline void lock_doms_cur(void) +{ + mutex_lock(&doms_cur_mutex); +} + +static inline void unlock_doms_cur(void) +{ + mutex_unlock(&doms_cur_mutex); } #else -static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { } +static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } +static inline void lock_task_group_list(void) { } +static inline void unlock_task_group_list(void) { } +static inline void lock_doms_cur(void) { } +static inline void unlock_doms_cur(void) { } #endif /* CONFIG_FAIR_GROUP_SCHED */ @@ -264,11 +362,57 @@ struct cfs_rq { /* Real-Time classes' related field in a runqueue: */ struct rt_rq { struct rt_prio_array active; - int rt_load_balance_idx; - struct list_head *rt_load_balance_head, *rt_load_balance_curr; + unsigned long rt_nr_running; +#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED + int highest_prio; /* highest queued rt task prio */ +#endif +#ifdef CONFIG_SMP + unsigned long rt_nr_migratory; + int overloaded; +#endif + int rt_throttled; + u64 rt_time; + +#ifdef CONFIG_FAIR_GROUP_SCHED + struct rq *rq; + struct list_head leaf_rt_rq_list; + struct task_group *tg; + struct sched_rt_entity *rt_se; +#endif +}; + +#ifdef CONFIG_SMP + +/* + * We add the notion of a root-domain which will be used to define per-domain + * variables. Each exclusive cpuset essentially defines an island domain by + * fully partitioning the member cpus from any other cpuset. Whenever a new + * exclusive cpuset is created, we also create and attach a new root-domain + * object. + * + */ +struct root_domain { + atomic_t refcount; + cpumask_t span; + cpumask_t online; + + /* + * The "RT overload" flag: it gets set if a CPU has more than + * one runnable RT task. + */ + cpumask_t rto_mask; + atomic_t rto_count; }; /* + * By default the system creates a single root-domain with all cpus as + * members (mimicking the global state we have today). + */ +static struct root_domain def_root_domain; + +#endif + +/* * This is the main, per-CPU runqueue data structure. * * Locking rule: those places that want to lock multiple runqueues @@ -296,11 +440,15 @@ struct rq { u64 nr_switches; struct cfs_rq cfs; + struct rt_rq rt; + u64 rt_period_expire; + int rt_throttled; + #ifdef CONFIG_FAIR_GROUP_SCHED /* list of leaf cfs_rq on this cpu: */ struct list_head leaf_cfs_rq_list; + struct list_head leaf_rt_rq_list; #endif - struct rt_rq rt; /* * This is part of a global counter where only the total sum @@ -317,7 +465,7 @@ struct rq { u64 clock, prev_clock_raw; s64 clock_max_delta; - unsigned int clock_warps, clock_overflows; + unsigned int clock_warps, clock_overflows, clock_underflows; u64 idle_clock; unsigned int clock_deep_idle_events; u64 tick_timestamp; @@ -325,6 +473,7 @@ struct rq { atomic_t nr_iowait; #ifdef CONFIG_SMP + struct root_domain *rd; struct sched_domain *sd; /* For active balancing */ @@ -337,6 +486,12 @@ struct rq { struct list_head migration_queue; #endif +#ifdef CONFIG_SCHED_HRTICK + unsigned long hrtick_flags; + ktime_t hrtick_expire; + struct hrtimer hrtick_timer; +#endif + #ifdef CONFIG_SCHEDSTATS /* latency stats */ struct sched_info rq_sched_info; @@ -363,7 +518,6 @@ struct rq { }; static DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); -static DEFINE_MUTEX(sched_hotcpu_mutex); static inline void check_preempt_curr(struct rq *rq, struct task_struct *p) { @@ -441,6 +595,23 @@ static void update_rq_clock(struct rq *rq) #define task_rq(p) cpu_rq(task_cpu(p)) #define cpu_curr(cpu) (cpu_rq(cpu)->curr) +unsigned long rt_needs_cpu(int cpu) +{ + struct rq *rq = cpu_rq(cpu); + u64 delta; + + if (!rq->rt_throttled) + return 0; + + if (rq->clock > rq->rt_period_expire) + return 1; + + delta = rq->rt_period_expire - rq->clock; + do_div(delta, NSEC_PER_SEC / HZ); + + return (unsigned long)delta; +} + /* * Tunables that become constants when CONFIG_SCHED_DEBUG is off: */ @@ -459,6 +630,8 @@ enum { SCHED_FEAT_START_DEBIT = 4, SCHED_FEAT_TREE_AVG = 8, SCHED_FEAT_APPROX_AVG = 16, + SCHED_FEAT_HRTICK = 32, + SCHED_FEAT_DOUBLE_TICK = 64, }; const_debug unsigned int sysctl_sched_features = @@ -466,7 +639,9 @@ const_debug unsigned int sysctl_sched_features = SCHED_FEAT_WAKEUP_PREEMPT * 1 | SCHED_FEAT_START_DEBIT * 1 | SCHED_FEAT_TREE_AVG * 0 | - SCHED_FEAT_APPROX_AVG * 0; + SCHED_FEAT_APPROX_AVG * 0 | + SCHED_FEAT_HRTICK * 1 | + SCHED_FEAT_DOUBLE_TICK * 0; #define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x) @@ -477,6 +652,21 @@ const_debug unsigned int sysctl_sched_features = const_debug unsigned int sysctl_sched_nr_migrate = 32; /* + * period over which we measure -rt task cpu usage in ms. + * default: 1s + */ +const_debug unsigned int sysctl_sched_rt_period = 1000; + +#define SCHED_RT_FRAC_SHIFT 16 +#define SCHED_RT_FRAC (1UL << SCHED_RT_FRAC_SHIFT) + +/* + * ratio of time -rt tasks may consume. + * default: 95% + */ +const_debug unsigned int sysctl_sched_rt_ratio = 62259; + +/* * For kernel-internal use: high-speed (but slightly incorrect) per-cpu * clock constructed from sched_clock(): */ @@ -508,10 +698,15 @@ EXPORT_SYMBOL_GPL(cpu_clock); # define finish_arch_switch(prev) do { } while (0) #endif +static inline int task_current(struct rq *rq, struct task_struct *p) +{ + return rq->curr == p; +} + #ifndef __ARCH_WANT_UNLOCKED_CTXSW static inline int task_running(struct rq *rq, struct task_struct *p) { - return rq->curr == p; + return task_current(rq, p); } static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next) @@ -540,7 +735,7 @@ static inline int task_running(struct rq *rq, struct task_struct *p) #ifdef CONFIG_SMP return p->oncpu; #else - return rq->curr == p; + return task_current(rq, p); #endif } @@ -674,9 +869,177 @@ void sched_clock_idle_wakeup_event(u64 delta_ns) rq->prev_clock_raw = now; rq->clock += delta_ns; spin_unlock(&rq->lock); + touch_softlockup_watchdog(); } EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); +static void __resched_task(struct task_struct *p, int tif_bit); + +static inline void resched_task(struct task_struct *p) +{ + __resched_task(p, TIF_NEED_RESCHED); +} + +#ifdef CONFIG_SCHED_HRTICK +/* + * Use HR-timers to deliver accurate preemption points. + * + * Its all a bit involved since we cannot program an hrt while holding the + * rq->lock. So what we do is store a state in in rq->hrtick_* and ask for a + * reschedule event. + * + * When we get rescheduled we reprogram the hrtick_timer outside of the + * rq->lock. + */ +static inline void resched_hrt(struct task_struct *p) +{ + __resched_task(p, TIF_HRTICK_RESCHED); +} + +static inline void resched_rq(struct rq *rq) +{ + unsigned long flags; + + spin_lock_irqsave(&rq->lock, flags); + resched_task(rq->curr); + spin_unlock_irqrestore(&rq->lock, flags); +} + +enum { + HRTICK_SET, /* re-programm hrtick_timer */ + HRTICK_RESET, /* not a new slice */ +}; + +/* + * Use hrtick when: + * - enabled by features + * - hrtimer is actually high res + */ +static inline int hrtick_enabled(struct rq *rq) +{ + if (!sched_feat(HRTICK)) + return 0; + return hrtimer_is_hres_active(&rq->hrtick_timer); +} + +/* + * Called to set the hrtick timer state. + * + * called with rq->lock held and irqs disabled + */ +static void hrtick_start(struct rq *rq, u64 delay, int reset) +{ + assert_spin_locked(&rq->lock); + + /* + * preempt at: now + delay + */ + rq->hrtick_expire = + ktime_add_ns(rq->hrtick_timer.base->get_time(), delay); + /* + * indicate we need to program the timer + */ + __set_bit(HRTICK_SET, &rq->hrtick_flags); + if (reset) + __set_bit(HRTICK_RESET, &rq->hrtick_flags); + + /* + * New slices are called from the schedule path and don't need a + * forced reschedule. + */ + if (reset) + resched_hrt(rq->curr); +} + +static void hrtick_clear(struct rq *rq) +{ + if (hrtimer_active(&rq->hrtick_timer)) + hrtimer_cancel(&rq->hrtick_timer); +} + +/* + * Update the timer from the possible pending state. + */ +static void hrtick_set(struct rq *rq) +{ + ktime_t time; + int set, reset; + unsigned long flags; + + WARN_ON_ONCE(cpu_of(rq) != smp_processor_id()); + + spin_lock_irqsave(&rq->lock, flags); + set = __test_and_clear_bit(HRTICK_SET, &rq->hrtick_flags); + reset = __test_and_clear_bit(HRTICK_RESET, &rq->hrtick_flags); + time = rq->hrtick_expire; + clear_thread_flag(TIF_HRTICK_RESCHED); + spin_unlock_irqrestore(&rq->lock, flags); + + if (set) { + hrtimer_start(&rq->hrtick_timer, time, HRTIMER_MODE_ABS); + if (reset && !hrtimer_active(&rq->hrtick_timer)) + resched_rq(rq); + } else + hrtick_clear(rq); +} + +/* + * High-resolution timer tick. + * Runs from hardirq context with interrupts disabled. + */ +static enum hrtimer_restart hrtick(struct hrtimer *timer) +{ + struct rq *rq = container_of(timer, struct rq, hrtick_timer); + + WARN_ON_ONCE(cpu_of(rq) != smp_processor_id()); + + spin_lock(&rq->lock); + __update_rq_clock(rq); + rq->curr->sched_class->task_tick(rq, rq->curr, 1); + spin_unlock(&rq->lock); + + return HRTIMER_NORESTART; +} + +static inline void init_rq_hrtick(struct rq *rq) +{ + rq->hrtick_flags = 0; + hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + rq->hrtick_timer.function = hrtick; + rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ; +} + +void hrtick_resched(void) +{ + struct rq *rq; + unsigned long flags; + + if (!test_thread_flag(TIF_HRTICK_RESCHED)) + return; + + local_irq_save(flags); + rq = cpu_rq(smp_processor_id()); + hrtick_set(rq); + local_irq_restore(flags); +} +#else +static inline void hrtick_clear(struct rq *rq) +{ +} + +static inline void hrtick_set(struct rq *rq) +{ +} + +static inline void init_rq_hrtick(struct rq *rq) +{ +} + +void hrtick_resched(void) +{ +} +#endif + /* * resched_task - mark a task 'to be rescheduled now'. * @@ -690,16 +1053,16 @@ EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event); #define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG) #endif -static void resched_task(struct task_struct *p) +static void __resched_task(struct task_struct *p, int tif_bit) { int cpu; assert_spin_locked(&task_rq(p)->lock); - if (unlikely(test_tsk_thread_flag(p, TIF_NEED_RESCHED))) + if (unlikely(test_tsk_thread_flag(p, tif_bit))) return; - set_tsk_thread_flag(p, TIF_NEED_RESCHED); + set_tsk_thread_flag(p, tif_bit); cpu = task_cpu(p); if (cpu == smp_processor_id()) @@ -722,10 +1085,10 @@ static void resched_cpu(int cpu) spin_unlock_irqrestore(&rq->lock, flags); } #else -static inline void resched_task(struct task_struct *p) +static void __resched_task(struct task_struct *p, int tif_bit) { assert_spin_locked(&task_rq(p)->lock); - set_tsk_need_resched(p); + set_tsk_thread_flag(p, tif_bit); } #endif @@ -865,6 +1228,23 @@ static void cpuacct_charge(struct task_struct *tsk, u64 cputime); static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} #endif +static inline void inc_cpu_load(struct rq *rq, unsigned long load) +{ + update_load_add(&rq->load, load); +} + +static inline void dec_cpu_load(struct rq *rq, unsigned long load) +{ + update_load_sub(&rq->load, load); +} + +#ifdef CONFIG_SMP +static unsigned long source_load(int cpu, int type); +static unsigned long target_load(int cpu, int type); +static unsigned long cpu_avg_load_per_task(int cpu); +static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd); +#endif /* CONFIG_SMP */ + #include "sched_stats.h" #include "sched_idletask.c" #include "sched_fair.c" @@ -875,41 +1255,14 @@ static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {} #define sched_class_highest (&rt_sched_class) -/* - * Update delta_exec, delta_fair fields for rq. - * - * delta_fair clock advances at a rate inversely proportional to - * total load (rq->load.weight) on the runqueue, while - * delta_exec advances at the same rate as wall-clock (provided - * cpu is not idle). - * - * delta_exec / delta_fair is a measure of the (smoothened) load on this - * runqueue over any given interval. This (smoothened) load is used - * during load balance. - * - * This function is called /before/ updating rq->load - * and when switching tasks. - */ -static inline void inc_load(struct rq *rq, const struct task_struct *p) -{ - update_load_add(&rq->load, p->se.load.weight); -} - -static inline void dec_load(struct rq *rq, const struct task_struct *p) -{ - update_load_sub(&rq->load, p->se.load.weight); -} - -static void inc_nr_running(struct task_struct *p, struct rq *rq) +static void inc_nr_running(struct rq *rq) { rq->nr_running++; - inc_load(rq, p); } -static void dec_nr_running(struct task_struct *p, struct rq *rq) +static void dec_nr_running(struct rq *rq) { rq->nr_running--; - dec_load(rq, p); } static void set_load_weight(struct task_struct *p) @@ -997,11 +1350,11 @@ static int effective_prio(struct task_struct *p) */ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup) { - if (p->state == TASK_UNINTERRUPTIBLE) + if (task_contributes_to_load(p)) rq->nr_uninterruptible--; enqueue_task(rq, p, wakeup); - inc_nr_running(p, rq); + inc_nr_running(rq); } /* @@ -1009,11 +1362,11 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup) */ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep) { - if (p->state == TASK_UNINTERRUPTIBLE) + if (task_contributes_to_load(p)) rq->nr_uninterruptible++; dequeue_task(rq, p, sleep); - dec_nr_running(p, rq); + dec_nr_running(rq); } /** @@ -1033,7 +1386,7 @@ unsigned long weighted_cpuload(const int cpu) static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) { - set_task_cfs_rq(p, cpu); + set_task_rq(p, cpu); #ifdef CONFIG_SMP /* * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be @@ -1045,12 +1398,24 @@ static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) #endif } +static inline void check_class_changed(struct rq *rq, struct task_struct *p, + const struct sched_class *prev_class, + int oldprio, int running) +{ + if (prev_class != p->sched_class) { + if (prev_class->switched_from) + prev_class->switched_from(rq, p, running); + p->sched_class->switched_to(rq, p, running); + } else + p->sched_class->prio_changed(rq, p, oldprio, running); +} + #ifdef CONFIG_SMP /* * Is this task likely cache-hot: */ -static inline int +static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd) { s64 delta; @@ -1275,7 +1640,7 @@ static unsigned long target_load(int cpu, int type) /* * Return the average load per task on the cpu's run queue */ -static inline unsigned long cpu_avg_load_per_task(int cpu) +static unsigned long cpu_avg_load_per_task(int cpu) { struct rq *rq = cpu_rq(cpu); unsigned long total = weighted_cpuload(cpu); @@ -1432,58 +1797,6 @@ static int sched_balance_self(int cpu, int flag) #endif /* CONFIG_SMP */ -/* - * wake_idle() will wake a task on an idle cpu if task->cpu is - * not idle and an idle cpu is available. The span of cpus to - * search starts with cpus closest then further out as needed, - * so we always favor a closer, idle cpu. - * - * Returns the CPU we should wake onto. - */ -#if defined(ARCH_HAS_SCHED_WAKE_IDLE) -static int wake_idle(int cpu, struct task_struct *p) -{ - cpumask_t tmp; - struct sched_domain *sd; - int i; - - /* - * If it is idle, then it is the best cpu to run this task. - * - * This cpu is also the best, if it has more than one task already. - * Siblings must be also busy(in most cases) as they didn't already - * pickup the extra load from this cpu and hence we need not check - * sibling runqueue info. This will avoid the checks and cache miss - * penalities associated with that. - */ - if (idle_cpu(cpu) || cpu_rq(cpu)->nr_running > 1) - return cpu; - - for_each_domain(cpu, sd) { - if (sd->flags & SD_WAKE_IDLE) { - cpus_and(tmp, sd->span, p->cpus_allowed); - for_each_cpu_mask(i, tmp) { - if (idle_cpu(i)) { - if (i != task_cpu(p)) { - schedstat_inc(p, - se.nr_wakeups_idle); - } - return i; - } - } - } else { - break; - } - } - return cpu; -} -#else -static inline int wake_idle(int cpu, struct task_struct *p) -{ - return cpu; -} -#endif - /*** * try_to_wake_up - wake up a thread * @p: the to-be-woken-up thread @@ -1504,11 +1817,6 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync) unsigned long flags; long old_state; struct rq *rq; -#ifdef CONFIG_SMP - struct sched_domain *sd, *this_sd = NULL; - unsigned long load, this_load; - int new_cpu; -#endif rq = task_rq_lock(p, &flags); old_state = p->state; @@ -1526,92 +1834,9 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync) if (unlikely(task_running(rq, p))) goto out_activate; - new_cpu = cpu; - - schedstat_inc(rq, ttwu_count); - if (cpu == this_cpu) { - schedstat_inc(rq, ttwu_local); - goto out_set_cpu; - } - - for_each_domain(this_cpu, sd) { - if (cpu_isset(cpu, sd->span)) { - schedstat_inc(sd, ttwu_wake_remote); - this_sd = sd; - break; - } - } - - if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed))) - goto out_set_cpu; - - /* - * Check for affine wakeup and passive balancing possibilities. - */ - if (this_sd) { - int idx = this_sd->wake_idx; - unsigned int imbalance; - - imbalance = 100 + (this_sd->imbalance_pct - 100) / 2; - - load = source_load(cpu, idx); - this_load = target_load(this_cpu, idx); - - new_cpu = this_cpu; /* Wake to this CPU if we can */ - - if (this_sd->flags & SD_WAKE_AFFINE) { - unsigned long tl = this_load; - unsigned long tl_per_task; - - /* - * Attract cache-cold tasks on sync wakeups: - */ - if (sync && !task_hot(p, rq->clock, this_sd)) - goto out_set_cpu; - - schedstat_inc(p, se.nr_wakeups_affine_attempts); - tl_per_task = cpu_avg_load_per_task(this_cpu); - - /* - * If sync wakeup then subtract the (maximum possible) - * effect of the currently running task from the load - * of the current CPU: - */ - if (sync) - tl -= current->se.load.weight; - - if ((tl <= load && - tl + target_load(cpu, idx) <= tl_per_task) || - 100*(tl + p->se.load.weight) <= imbalance*load) { - /* - * This domain has SD_WAKE_AFFINE and - * p is cache cold in this domain, and - * there is no bad imbalance. - */ - schedstat_inc(this_sd, ttwu_move_affine); - schedstat_inc(p, se.nr_wakeups_affine); - goto out_set_cpu; - } - } - - /* - * Start passive balancing when half the imbalance_pct - * limit is reached. - */ - if (this_sd->flags & SD_WAKE_BALANCE) { - if (imbalance*this_load <= 100*load) { - schedstat_inc(this_sd, ttwu_move_balance); - schedstat_inc(p, se.nr_wakeups_passive); - goto out_set_cpu; - } - } - } - - new_cpu = cpu; /* Could not wake to this_cpu. Wake to cpu instead */ -out_set_cpu: - new_cpu = wake_idle(new_cpu, p); - if (new_cpu != cpu) { - set_task_cpu(p, new_cpu); + cpu = p->sched_class->select_task_rq(p, sync); + if (cpu != orig_cpu) { + set_task_cpu(p, cpu); task_rq_unlock(rq, &flags); /* might preempt at this point */ rq = task_rq_lock(p, &flags); @@ -1625,6 +1850,21 @@ out_set_cpu: cpu = task_cpu(p); } +#ifdef CONFIG_SCHEDSTATS + schedstat_inc(rq, ttwu_count); + if (cpu == this_cpu) + schedstat_inc(rq, ttwu_local); + else { + struct sched_domain *sd; + for_each_domain(this_cpu, sd) { + if (cpu_isset(cpu, sd->span)) { + schedstat_inc(sd, ttwu_wake_remote); + break; + } + } + } +#endif + out_activate: #endif /* CONFIG_SMP */ schedstat_inc(p, se.nr_wakeups); @@ -1643,6 +1883,10 @@ out_activate: out_running: p->state = TASK_RUNNING; +#ifdef CONFIG_SMP + if (p->sched_class->task_wake_up) + p->sched_class->task_wake_up(rq, p); +#endif out: task_rq_unlock(rq, &flags); @@ -1651,8 +1895,7 @@ out: int fastcall wake_up_process(struct task_struct *p) { - return try_to_wake_up(p, TASK_STOPPED | TASK_TRACED | - TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE, 0); + return try_to_wake_up(p, TASK_ALL, 0); } EXPORT_SYMBOL(wake_up_process); @@ -1685,7 +1928,7 @@ static void __sched_fork(struct task_struct *p) p->se.wait_max = 0; #endif - INIT_LIST_HEAD(&p->run_list); + INIT_LIST_HEAD(&p->rt.run_list); p->se.on_rq = 0; #ifdef CONFIG_PREEMPT_NOTIFIERS @@ -1762,9 +2005,13 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags) * management (if any): */ p->sched_class->task_new(rq, p); - inc_nr_running(p, rq); + inc_nr_running(rq); } check_preempt_curr(rq, p); +#ifdef CONFIG_SMP + if (p->sched_class->task_wake_up) + p->sched_class->task_wake_up(rq, p); +#endif task_rq_unlock(rq, &flags); } @@ -1885,6 +2132,11 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev) prev_state = prev->state; finish_arch_switch(prev); finish_lock_switch(rq, prev); +#ifdef CONFIG_SMP + if (current->sched_class->post_schedule) + current->sched_class->post_schedule(rq); +#endif + fire_sched_in_preempt_notifiers(current); if (mm) mmdrop(mm); @@ -2118,11 +2370,13 @@ static void double_rq_unlock(struct rq *rq1, struct rq *rq2) /* * double_lock_balance - lock the busiest runqueue, this_rq is locked already. */ -static void double_lock_balance(struct rq *this_rq, struct rq *busiest) +static int double_lock_balance(struct rq *this_rq, struct rq *busiest) __releases(this_rq->lock) __acquires(busiest->lock) __acquires(this_rq->lock) { + int ret = 0; + if (unlikely(!irqs_disabled())) { /* printk() doesn't work good under rq->lock */ spin_unlock(&this_rq->lock); @@ -2133,9 +2387,11 @@ static void double_lock_balance(struct rq *this_rq, struct rq *busiest) spin_unlock(&this_rq->lock); spin_lock(&busiest->lock); spin_lock(&this_rq->lock); + ret = 1; } else spin_lock(&busiest->lock); } + return ret; } /* @@ -3334,7 +3590,7 @@ unsigned long long task_sched_runtime(struct task_struct *p) rq = task_rq_lock(p, &flags); ns = p->se.sum_exec_runtime; - if (rq->curr == p) { + if (task_current(rq, p)) { update_rq_clock(rq); delta_exec = rq->clock - p->se.exec_start; if ((s64)delta_exec > 0) @@ -3479,12 +3735,14 @@ void scheduler_tick(void) /* * Let rq->clock advance by at least TICK_NSEC: */ - if (unlikely(rq->clock < next_tick)) + if (unlikely(rq->clock < next_tick)) { rq->clock = next_tick; + rq->clock_underflows++; + } rq->tick_timestamp = rq->clock; update_cpu_load(rq); - if (curr != rq->idle) /* FIXME: needed? */ - curr->sched_class->task_tick(rq, curr); + curr->sched_class->task_tick(rq, curr, 0); + update_sched_rt_period(rq); spin_unlock(&rq->lock); #ifdef CONFIG_SMP @@ -3630,6 +3888,8 @@ need_resched_nonpreemptible: schedule_debug(prev); + hrtick_clear(rq); + /* * Do the rq-clock update outside the rq lock: */ @@ -3648,6 +3908,11 @@ need_resched_nonpreemptible: switch_count = &prev->nvcsw; } +#ifdef CONFIG_SMP + if (prev->sched_class->pre_schedule) + prev->sched_class->pre_schedule(rq, prev); +#endif + if (unlikely(!rq->nr_running)) idle_balance(cpu, rq); @@ -3662,14 +3927,20 @@ need_resched_nonpreemptible: ++*switch_count; context_switch(rq, prev, next); /* unlocks the rq */ + /* + * the context switch might have flipped the stack from under + * us, hence refresh the local variables. + */ + cpu = smp_processor_id(); + rq = cpu_rq(cpu); } else spin_unlock_irq(&rq->lock); - if (unlikely(reacquire_kernel_lock(current) < 0)) { - cpu = smp_processor_id(); - rq = cpu_rq(cpu); + hrtick_set(rq); + + if (unlikely(reacquire_kernel_lock(current) < 0)) goto need_resched_nonpreemptible; - } + preempt_enable_no_resched(); if (unlikely(test_thread_flag(TIF_NEED_RESCHED))) goto need_resched; @@ -3685,10 +3956,9 @@ EXPORT_SYMBOL(schedule); asmlinkage void __sched preempt_schedule(void) { struct thread_info *ti = current_thread_info(); -#ifdef CONFIG_PREEMPT_BKL struct task_struct *task = current; int saved_lock_depth; -#endif + /* * If there is a non-zero preempt_count or interrupts are disabled, * we do not want to preempt the current task. Just return.. @@ -3704,14 +3974,10 @@ asmlinkage void __sched preempt_schedule(void) * clear ->lock_depth so that schedule() doesnt * auto-release the semaphore: */ -#ifdef CONFIG_PREEMPT_BKL saved_lock_depth = task->lock_depth; task->lock_depth = -1; -#endif schedule(); -#ifdef CONFIG_PREEMPT_BKL task->lock_depth = saved_lock_depth; -#endif sub_preempt_count(PREEMPT_ACTIVE); /* @@ -3732,10 +3998,9 @@ EXPORT_SYMBOL(preempt_schedule); asmlinkage void __sched preempt_schedule_irq(void) { struct thread_info *ti = current_thread_info(); -#ifdef CONFIG_PREEMPT_BKL struct task_struct *task = current; int saved_lock_depth; -#endif + /* Catch callers which need to be fixed */ BUG_ON(ti->preempt_count || !irqs_disabled()); @@ -3747,16 +4012,12 @@ asmlinkage void __sched preempt_schedule_irq(void) * clear ->lock_depth so that schedule() doesnt * auto-release the semaphore: */ -#ifdef CONFIG_PREEMPT_BKL saved_lock_depth = task->lock_depth; task->lock_depth = -1; -#endif local_irq_enable(); schedule(); local_irq_disable(); -#ifdef CONFIG_PREEMPT_BKL task->lock_depth = saved_lock_depth; -#endif sub_preempt_count(PREEMPT_ACTIVE); /* @@ -3862,8 +4123,7 @@ void complete(struct completion *x) spin_lock_irqsave(&x->wait.lock, flags); x->done++; - __wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, - 1, 0, NULL); + __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL); spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete); @@ -3874,8 +4134,7 @@ void complete_all(struct completion *x) spin_lock_irqsave(&x->wait.lock, flags); x->done += UINT_MAX/2; - __wake_up_common(&x->wait, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, - 0, 0, NULL); + __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL); spin_unlock_irqrestore(&x->wait.lock, flags); } EXPORT_SYMBOL(complete_all); @@ -3889,8 +4148,10 @@ do_wait_for_common(struct completion *x, long timeout, int state) wait.flags |= WQ_FLAG_EXCLUSIVE; __add_wait_queue_tail(&x->wait, &wait); do { - if (state == TASK_INTERRUPTIBLE && - signal_pending(current)) { + if ((state == TASK_INTERRUPTIBLE && + signal_pending(current)) || + (state == TASK_KILLABLE && + fatal_signal_pending(current))) { __remove_wait_queue(&x->wait, &wait); return -ERESTARTSYS; } @@ -3950,6 +4211,15 @@ wait_for_completion_interruptible_timeout(struct completion *x, } EXPORT_SYMBOL(wait_for_completion_interruptible_timeout); +int __sched wait_for_completion_killable(struct completion *x) +{ + long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE); + if (t == -ERESTARTSYS) + return t; + return 0; +} +EXPORT_SYMBOL(wait_for_completion_killable); + static long __sched sleep_on_common(wait_queue_head_t *q, int state, long timeout) { @@ -4013,6 +4283,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) unsigned long flags; int oldprio, on_rq, running; struct rq *rq; + const struct sched_class *prev_class = p->sched_class; BUG_ON(prio < 0 || prio > MAX_PRIO); @@ -4021,7 +4292,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) oldprio = p->prio; on_rq = p->se.on_rq; - running = task_running(rq, p); + running = task_current(rq, p); if (on_rq) { dequeue_task(rq, p, 0); if (running) @@ -4038,18 +4309,10 @@ void rt_mutex_setprio(struct task_struct *p, int prio) if (on_rq) { if (running) p->sched_class->set_curr_task(rq); + enqueue_task(rq, p, 0); - /* - * Reschedule if we are currently running on this runqueue and - * our priority decreased, or if we are not currently running on - * this runqueue and our priority is higher than the current's - */ - if (running) { - if (p->prio > oldprio) - resched_task(rq->curr); - } else { - check_preempt_curr(rq, p); - } + + check_class_changed(rq, p, prev_class, oldprio, running); } task_rq_unlock(rq, &flags); } @@ -4081,10 +4344,8 @@ void set_user_nice(struct task_struct *p, long nice) goto out_unlock; } on_rq = p->se.on_rq; - if (on_rq) { + if (on_rq) dequeue_task(rq, p, 0); - dec_load(rq, p); - } p->static_prio = NICE_TO_PRIO(nice); set_load_weight(p); @@ -4094,7 +4355,6 @@ void set_user_nice(struct task_struct *p, long nice) if (on_rq) { enqueue_task(rq, p, 0); - inc_load(rq, p); /* * If the task increased its priority or is running and * lowered its priority, then reschedule its CPU: @@ -4252,6 +4512,7 @@ int sched_setscheduler(struct task_struct *p, int policy, { int retval, oldprio, oldpolicy = -1, on_rq, running; unsigned long flags; + const struct sched_class *prev_class = p->sched_class; struct rq *rq; /* may grab non-irq protected spin_locks */ @@ -4332,7 +4593,7 @@ recheck: } update_rq_clock(rq); on_rq = p->se.on_rq; - running = task_running(rq, p); + running = task_current(rq, p); if (on_rq) { deactivate_task(rq, p, 0); if (running) @@ -4345,18 +4606,10 @@ recheck: if (on_rq) { if (running) p->sched_class->set_curr_task(rq); + activate_task(rq, p, 0); - /* - * Reschedule if we are currently running on this runqueue and - * our priority decreased, or if we are not currently running on - * this runqueue and our priority is higher than the current's - */ - if (running) { - if (p->prio > oldprio) - resched_task(rq->curr); - } else { - check_preempt_curr(rq, p); - } + + check_class_changed(rq, p, prev_class, oldprio, running); } __task_rq_unlock(rq); spin_unlock_irqrestore(&p->pi_lock, flags); @@ -4484,13 +4737,13 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask) struct task_struct *p; int retval; - mutex_lock(&sched_hotcpu_mutex); + get_online_cpus(); read_lock(&tasklist_lock); p = find_process_by_pid(pid); if (!p) { read_unlock(&tasklist_lock); - mutex_unlock(&sched_hotcpu_mutex); + put_online_cpus(); return -ESRCH; } @@ -4530,7 +4783,7 @@ long sched_setaffinity(pid_t pid, cpumask_t new_mask) } out_unlock: put_task_struct(p); - mutex_unlock(&sched_hotcpu_mutex); + put_online_cpus(); return retval; } @@ -4587,7 +4840,7 @@ long sched_getaffinity(pid_t pid, cpumask_t *mask) struct task_struct *p; int retval; - mutex_lock(&sched_hotcpu_mutex); + get_online_cpus(); read_lock(&tasklist_lock); retval = -ESRCH; @@ -4603,7 +4856,7 @@ long sched_getaffinity(pid_t pid, cpumask_t *mask) out_unlock: read_unlock(&tasklist_lock); - mutex_unlock(&sched_hotcpu_mutex); + put_online_cpus(); return retval; } @@ -4677,7 +4930,8 @@ static void __cond_resched(void) } while (need_resched()); } -int __sched cond_resched(void) +#if !defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY) +int __sched _cond_resched(void) { if (need_resched() && !(preempt_count() & PREEMPT_ACTIVE) && system_state == SYSTEM_RUNNING) { @@ -4686,7 +4940,8 @@ int __sched cond_resched(void) } return 0; } -EXPORT_SYMBOL(cond_resched); +EXPORT_SYMBOL(_cond_resched); +#endif /* * cond_resched_lock() - if a reschedule is pending, drop the given lock, @@ -4698,19 +4953,15 @@ EXPORT_SYMBOL(cond_resched); */ int cond_resched_lock(spinlock_t *lock) { + int resched = need_resched() && system_state == SYSTEM_RUNNING; int ret = 0; - if (need_lockbreak(lock)) { + if (spin_needbreak(lock) || resched) { spin_unlock(lock); - cpu_relax(); - ret = 1; - spin_lock(lock); - } - if (need_resched() && system_state == SYSTEM_RUNNING) { - spin_release(&lock->dep_map, 1, _THIS_IP_); - _raw_spin_unlock(lock); - preempt_enable_no_resched(); - __cond_resched(); + if (resched && need_resched()) + __cond_resched(); + else + cpu_relax(); ret = 1; spin_lock(lock); } @@ -4884,7 +5135,7 @@ out_unlock: static const char stat_nam[] = "RSDTtZX"; -static void show_task(struct task_struct *p) +void sched_show_task(struct task_struct *p) { unsigned long free = 0; unsigned state; @@ -4912,10 +5163,9 @@ static void show_task(struct task_struct *p) } #endif printk(KERN_CONT "%5lu %5d %6d\n", free, - task_pid_nr(p), task_pid_nr(p->parent)); + task_pid_nr(p), task_pid_nr(p->real_parent)); - if (state != TASK_RUNNING) - show_stack(p, NULL); + show_stack(p, NULL); } void show_state_filter(unsigned long state_filter) @@ -4937,7 +5187,7 @@ void show_state_filter(unsigned long state_filter) */ touch_nmi_watchdog(); if (!state_filter || (p->state & state_filter)) - show_task(p); + sched_show_task(p); } while_each_thread(g, p); touch_all_softlockup_watchdogs(); @@ -4986,11 +5236,8 @@ void __cpuinit init_idle(struct task_struct *idle, int cpu) spin_unlock_irqrestore(&rq->lock, flags); /* Set the preempt count _outside_ the spinlocks! */ -#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_BKL) - task_thread_info(idle)->preempt_count = (idle->lock_depth >= 0); -#else task_thread_info(idle)->preempt_count = 0; -#endif + /* * The idle tasks have their own, simple scheduling class: */ @@ -5071,7 +5318,13 @@ int set_cpus_allowed(struct task_struct *p, cpumask_t new_mask) goto out; } - p->cpus_allowed = new_mask; + if (p->sched_class->set_cpus_allowed) + p->sched_class->set_cpus_allowed(p, &new_mask); + else { + p->cpus_allowed = new_mask; + p->rt.nr_cpus_allowed = cpus_weight(new_mask); + } + /* Can the task run on the task's current CPU? If so, we're done */ if (cpu_isset(task_cpu(p), new_mask)) goto out; @@ -5563,9 +5816,6 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) struct rq *rq; switch (action) { - case CPU_LOCK_ACQUIRE: - mutex_lock(&sched_hotcpu_mutex); - break; case CPU_UP_PREPARE: case CPU_UP_PREPARE_FROZEN: @@ -5584,6 +5834,15 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) case CPU_ONLINE_FROZEN: /* Strictly unnecessary, as first user will wake it. */ wake_up_process(cpu_rq(cpu)->migration_thread); + + /* Update our root-domain */ + rq = cpu_rq(cpu); + spin_lock_irqsave(&rq->lock, flags); + if (rq->rd) { + BUG_ON(!cpu_isset(cpu, rq->rd->span)); + cpu_set(cpu, rq->rd->online); + } + spin_unlock_irqrestore(&rq->lock, flags); break; #ifdef CONFIG_HOTPLUG_CPU @@ -5634,10 +5893,18 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu) } spin_unlock_irq(&rq->lock); break; -#endif - case CPU_LOCK_RELEASE: - mutex_unlock(&sched_hotcpu_mutex); + + case CPU_DOWN_PREPARE: + /* Update our root-domain */ + rq = cpu_rq(cpu); + spin_lock_irqsave(&rq->lock, flags); + if (rq->rd) { + BUG_ON(!cpu_isset(cpu, rq->rd->span)); + cpu_clear(cpu, rq->rd->online); + } + spin_unlock_irqrestore(&rq->lock, flags); break; +#endif } return NOTIFY_OK; } @@ -5825,11 +6092,76 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) return 1; } +static void rq_attach_root(struct rq *rq, struct root_domain *rd) +{ + unsigned long flags; + const struct sched_class *class; + + spin_lock_irqsave(&rq->lock, flags); + + if (rq->rd) { + struct root_domain *old_rd = rq->rd; + + for (class = sched_class_highest; class; class = class->next) { + if (class->leave_domain) + class->leave_domain(rq); + } + + cpu_clear(rq->cpu, old_rd->span); + cpu_clear(rq->cpu, old_rd->online); + + if (atomic_dec_and_test(&old_rd->refcount)) + kfree(old_rd); + } + + atomic_inc(&rd->refcount); + rq->rd = rd; + + cpu_set(rq->cpu, rd->span); + if (cpu_isset(rq->cpu, cpu_online_map)) + cpu_set(rq->cpu, rd->online); + + for (class = sched_class_highest; class; class = class->next) { + if (class->join_domain) + class->join_domain(rq); + } + + spin_unlock_irqrestore(&rq->lock, flags); +} + +static void init_rootdomain(struct root_domain *rd) +{ + memset(rd, 0, sizeof(*rd)); + + cpus_clear(rd->span); + cpus_clear(rd->online); +} + +static void init_defrootdomain(void) +{ + init_rootdomain(&def_root_domain); + atomic_set(&def_root_domain.refcount, 1); +} + +static struct root_domain *alloc_rootdomain(void) +{ + struct root_domain *rd; + + rd = kmalloc(sizeof(*rd), GFP_KERNEL); + if (!rd) + return NULL; + + init_rootdomain(rd); + + return rd; +} + /* - * Attach the domain 'sd' to 'cpu' as its base domain. Callers must + * Attach the domain 'sd' to 'cpu' as its base domain. Callers must * hold the hotplug lock. */ -static void cpu_attach_domain(struct sched_domain *sd, int cpu) +static void +cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) { struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; @@ -5854,6 +6186,7 @@ static void cpu_attach_domain(struct sched_domain *sd, int cpu) sched_domain_debug(sd, cpu); + rq_attach_root(rq, rd); rcu_assign_pointer(rq->sd, sd); } @@ -6222,6 +6555,7 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) static int build_sched_domains(const cpumask_t *cpu_map) { int i; + struct root_domain *rd; #ifdef CONFIG_NUMA struct sched_group **sched_group_nodes = NULL; int sd_allnodes = 0; @@ -6238,6 +6572,12 @@ static int build_sched_domains(const cpumask_t *cpu_map) sched_group_nodes_bycpu[first_cpu(*cpu_map)] = sched_group_nodes; #endif + rd = alloc_rootdomain(); + if (!rd) { + printk(KERN_WARNING "Cannot alloc root domain\n"); + return -ENOMEM; + } + /* * Set up domains for cpus specified by the cpu_map. */ @@ -6454,7 +6794,7 @@ static int build_sched_domains(const cpumask_t *cpu_map) #else sd = &per_cpu(phys_domains, i); #endif - cpu_attach_domain(sd, i); + cpu_attach_domain(sd, rd, i); } return 0; @@ -6512,7 +6852,7 @@ static void detach_destroy_domains(const cpumask_t *cpu_map) unregister_sched_domain_sysctl(); for_each_cpu_mask(i, *cpu_map) - cpu_attach_domain(NULL, i); + cpu_attach_domain(NULL, &def_root_domain, i); synchronize_sched(); arch_destroy_sched_domains(cpu_map); } @@ -6542,6 +6882,8 @@ void partition_sched_domains(int ndoms_new, cpumask_t *doms_new) { int i, j; + lock_doms_cur(); + /* always unregister in case we don't destroy any domains */ unregister_sched_domain_sysctl(); @@ -6582,6 +6924,8 @@ match2: ndoms_cur = ndoms_new; register_sched_domain_sysctl(); + + unlock_doms_cur(); } #if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT) @@ -6589,10 +6933,10 @@ static int arch_reinit_sched_domains(void) { int err; - mutex_lock(&sched_hotcpu_mutex); + get_online_cpus(); detach_destroy_domains(&cpu_online_map); err = arch_init_sched_domains(&cpu_online_map); - mutex_unlock(&sched_hotcpu_mutex); + put_online_cpus(); return err; } @@ -6703,12 +7047,12 @@ void __init sched_init_smp(void) { cpumask_t non_isolated_cpus; - mutex_lock(&sched_hotcpu_mutex); + get_online_cpus(); arch_init_sched_domains(&cpu_online_map); cpus_andnot(non_isolated_cpus, cpu_possible_map, cpu_isolated_map); if (cpus_empty(non_isolated_cpus)) cpu_set(smp_processor_id(), non_isolated_cpus); - mutex_unlock(&sched_hotcpu_mutex); + put_online_cpus(); /* XXX: Theoretical race here - CPU may be hotplugged now */ hotcpu_notifier(update_sched_domains, 0); @@ -6716,6 +7060,21 @@ void __init sched_init_smp(void) if (set_cpus_allowed(current, non_isolated_cpus) < 0) BUG(); sched_init_granularity(); + +#ifdef CONFIG_FAIR_GROUP_SCHED + if (nr_cpu_ids == 1) + return; + + lb_monitor_task = kthread_create(load_balance_monitor, NULL, + "group_balance"); + if (!IS_ERR(lb_monitor_task)) { + lb_monitor_task->flags |= PF_NOFREEZE; + wake_up_process(lb_monitor_task); + } else { + printk(KERN_ERR "Could not create load balance monitor thread" + "(error = %ld) \n", PTR_ERR(lb_monitor_task)); + } +#endif } #else void __init sched_init_smp(void) @@ -6740,13 +7099,87 @@ static void init_cfs_rq(struct cfs_rq *cfs_rq, struct rq *rq) cfs_rq->min_vruntime = (u64)(-(1LL << 20)); } +static void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq) +{ + struct rt_prio_array *array; + int i; + + array = &rt_rq->active; + for (i = 0; i < MAX_RT_PRIO; i++) { + INIT_LIST_HEAD(array->queue + i); + __clear_bit(i, array->bitmap); + } + /* delimiter for bitsearch: */ + __set_bit(MAX_RT_PRIO, array->bitmap); + +#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED + rt_rq->highest_prio = MAX_RT_PRIO; +#endif +#ifdef CONFIG_SMP + rt_rq->rt_nr_migratory = 0; + rt_rq->overloaded = 0; +#endif + + rt_rq->rt_time = 0; + rt_rq->rt_throttled = 0; + +#ifdef CONFIG_FAIR_GROUP_SCHED + rt_rq->rq = rq; +#endif +} + +#ifdef CONFIG_FAIR_GROUP_SCHED +static void init_tg_cfs_entry(struct rq *rq, struct task_group *tg, + struct cfs_rq *cfs_rq, struct sched_entity *se, + int cpu, int add) +{ + tg->cfs_rq[cpu] = cfs_rq; + init_cfs_rq(cfs_rq, rq); + cfs_rq->tg = tg; + if (add) + list_add(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list); + + tg->se[cpu] = se; + se->cfs_rq = &rq->cfs; + se->my_q = cfs_rq; + se->load.weight = tg->shares; + se->load.inv_weight = div64_64(1ULL<<32, se->load.weight); + se->parent = NULL; +} + +static void init_tg_rt_entry(struct rq *rq, struct task_group *tg, + struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, + int cpu, int add) +{ + tg->rt_rq[cpu] = rt_rq; + init_rt_rq(rt_rq, rq); + rt_rq->tg = tg; + rt_rq->rt_se = rt_se; + if (add) + list_add(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list); + + tg->rt_se[cpu] = rt_se; + rt_se->rt_rq = &rq->rt; + rt_se->my_q = rt_rq; + rt_se->parent = NULL; + INIT_LIST_HEAD(&rt_se->run_list); +} +#endif + void __init sched_init(void) { int highest_cpu = 0; int i, j; +#ifdef CONFIG_SMP + init_defrootdomain(); +#endif + +#ifdef CONFIG_FAIR_GROUP_SCHED + list_add(&init_task_group.list, &task_groups); +#endif + for_each_possible_cpu(i) { - struct rt_prio_array *array; struct rq *rq; rq = cpu_rq(i); @@ -6755,52 +7188,39 @@ void __init sched_init(void) rq->nr_running = 0; rq->clock = 1; init_cfs_rq(&rq->cfs, rq); + init_rt_rq(&rq->rt, rq); #ifdef CONFIG_FAIR_GROUP_SCHED - INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); - { - struct cfs_rq *cfs_rq = &per_cpu(init_cfs_rq, i); - struct sched_entity *se = - &per_cpu(init_sched_entity, i); - - init_cfs_rq_p[i] = cfs_rq; - init_cfs_rq(cfs_rq, rq); - cfs_rq->tg = &init_task_group; - list_add(&cfs_rq->leaf_cfs_rq_list, - &rq->leaf_cfs_rq_list); - - init_sched_entity_p[i] = se; - se->cfs_rq = &rq->cfs; - se->my_q = cfs_rq; - se->load.weight = init_task_group_load; - se->load.inv_weight = - div64_64(1ULL<<32, init_task_group_load); - se->parent = NULL; - } init_task_group.shares = init_task_group_load; - spin_lock_init(&init_task_group.lock); + INIT_LIST_HEAD(&rq->leaf_cfs_rq_list); + init_tg_cfs_entry(rq, &init_task_group, + &per_cpu(init_cfs_rq, i), + &per_cpu(init_sched_entity, i), i, 1); + + init_task_group.rt_ratio = sysctl_sched_rt_ratio; /* XXX */ + INIT_LIST_HEAD(&rq->leaf_rt_rq_list); + init_tg_rt_entry(rq, &init_task_group, + &per_cpu(init_rt_rq, i), + &per_cpu(init_sched_rt_entity, i), i, 1); #endif + rq->rt_period_expire = 0; + rq->rt_throttled = 0; for (j = 0; j < CPU_LOAD_IDX_MAX; j++) rq->cpu_load[j] = 0; #ifdef CONFIG_SMP rq->sd = NULL; + rq->rd = NULL; rq->active_balance = 0; rq->next_balance = jiffies; rq->push_cpu = 0; rq->cpu = i; rq->migration_thread = NULL; INIT_LIST_HEAD(&rq->migration_queue); + rq_attach_root(rq, &def_root_domain); #endif + init_rq_hrtick(rq); atomic_set(&rq->nr_iowait, 0); - - array = &rq->rt.active; - for (j = 0; j < MAX_RT_PRIO; j++) { - INIT_LIST_HEAD(array->queue + j); - __clear_bit(j, array->bitmap); - } highest_cpu = i; - /* delimiter for bitsearch: */ - __set_bit(MAX_RT_PRIO, array->bitmap); } set_load_weight(&init_task); @@ -6969,12 +7389,187 @@ void set_curr_task(int cpu, struct task_struct *p) #ifdef CONFIG_FAIR_GROUP_SCHED +#ifdef CONFIG_SMP +/* + * distribute shares of all task groups among their schedulable entities, + * to reflect load distribution across cpus. + */ +static int rebalance_shares(struct sched_domain *sd, int this_cpu) +{ + struct cfs_rq *cfs_rq; + struct rq *rq = cpu_rq(this_cpu); + cpumask_t sdspan = sd->span; + int balanced = 1; + + /* Walk thr' all the task groups that we have */ + for_each_leaf_cfs_rq(rq, cfs_rq) { + int i; + unsigned long total_load = 0, total_shares; + struct task_group *tg = cfs_rq->tg; + + /* Gather total task load of this group across cpus */ + for_each_cpu_mask(i, sdspan) + total_load += tg->cfs_rq[i]->load.weight; + + /* Nothing to do if this group has no load */ + if (!total_load) + continue; + + /* + * tg->shares represents the number of cpu shares the task group + * is eligible to hold on a single cpu. On N cpus, it is + * eligible to hold (N * tg->shares) number of cpu shares. + */ + total_shares = tg->shares * cpus_weight(sdspan); + + /* + * redistribute total_shares across cpus as per the task load + * distribution. + */ + for_each_cpu_mask(i, sdspan) { + unsigned long local_load, local_shares; + + local_load = tg->cfs_rq[i]->load.weight; + local_shares = (local_load * total_shares) / total_load; + if (!local_shares) + local_shares = MIN_GROUP_SHARES; + if (local_shares == tg->se[i]->load.weight) + continue; + + spin_lock_irq(&cpu_rq(i)->lock); + set_se_shares(tg->se[i], local_shares); + spin_unlock_irq(&cpu_rq(i)->lock); + balanced = 0; + } + } + + return balanced; +} + +/* + * How frequently should we rebalance_shares() across cpus? + * + * The more frequently we rebalance shares, the more accurate is the fairness + * of cpu bandwidth distribution between task groups. However higher frequency + * also implies increased scheduling overhead. + * + * sysctl_sched_min_bal_int_shares represents the minimum interval between + * consecutive calls to rebalance_shares() in the same sched domain. + * + * sysctl_sched_max_bal_int_shares represents the maximum interval between + * consecutive calls to rebalance_shares() in the same sched domain. + * + * These settings allows for the appropriate trade-off between accuracy of + * fairness and the associated overhead. + * + */ + +/* default: 8ms, units: milliseconds */ +const_debug unsigned int sysctl_sched_min_bal_int_shares = 8; + +/* default: 128ms, units: milliseconds */ +const_debug unsigned int sysctl_sched_max_bal_int_shares = 128; + +/* kernel thread that runs rebalance_shares() periodically */ +static int load_balance_monitor(void *unused) +{ + unsigned int timeout = sysctl_sched_min_bal_int_shares; + struct sched_param schedparm; + int ret; + + /* + * We don't want this thread's execution to be limited by the shares + * assigned to default group (init_task_group). Hence make it run + * as a SCHED_RR RT task at the lowest priority. + */ + schedparm.sched_priority = 1; + ret = sched_setscheduler(current, SCHED_RR, &schedparm); + if (ret) + printk(KERN_ERR "Couldn't set SCHED_RR policy for load balance" + " monitor thread (error = %d) \n", ret); + + while (!kthread_should_stop()) { + int i, cpu, balanced = 1; + + /* Prevent cpus going down or coming up */ + get_online_cpus(); + /* lockout changes to doms_cur[] array */ + lock_doms_cur(); + /* + * Enter a rcu read-side critical section to safely walk rq->sd + * chain on various cpus and to walk task group list + * (rq->leaf_cfs_rq_list) in rebalance_shares(). + */ + rcu_read_lock(); + + for (i = 0; i < ndoms_cur; i++) { + cpumask_t cpumap = doms_cur[i]; + struct sched_domain *sd = NULL, *sd_prev = NULL; + + cpu = first_cpu(cpumap); + + /* Find the highest domain at which to balance shares */ + for_each_domain(cpu, sd) { + if (!(sd->flags & SD_LOAD_BALANCE)) + continue; + sd_prev = sd; + } + + sd = sd_prev; + /* sd == NULL? No load balance reqd in this domain */ + if (!sd) + continue; + + balanced &= rebalance_shares(sd, cpu); + } + + rcu_read_unlock(); + + unlock_doms_cur(); + put_online_cpus(); + + if (!balanced) + timeout = sysctl_sched_min_bal_int_shares; + else if (timeout < sysctl_sched_max_bal_int_shares) + timeout *= 2; + + msleep_interruptible(timeout); + } + + return 0; +} +#endif /* CONFIG_SMP */ + +static void free_sched_group(struct task_group *tg) +{ + int i; + + for_each_possible_cpu(i) { + if (tg->cfs_rq) + kfree(tg->cfs_rq[i]); + if (tg->se) + kfree(tg->se[i]); + if (tg->rt_rq) + kfree(tg->rt_rq[i]); + if (tg->rt_se) + kfree(tg->rt_se[i]); + } + + kfree(tg->cfs_rq); + kfree(tg->se); + kfree(tg->rt_rq); + kfree(tg->rt_se); + kfree(tg); +} + /* allocate runqueue etc for a new task group */ struct task_group *sched_create_group(void) { struct task_group *tg; struct cfs_rq *cfs_rq; struct sched_entity *se; + struct rt_rq *rt_rq; + struct sched_rt_entity *rt_se; struct rq *rq; int i; @@ -6988,97 +7583,89 @@ struct task_group *sched_create_group(void) tg->se = kzalloc(sizeof(se) * NR_CPUS, GFP_KERNEL); if (!tg->se) goto err; + tg->rt_rq = kzalloc(sizeof(rt_rq) * NR_CPUS, GFP_KERNEL); + if (!tg->rt_rq) + goto err; + tg->rt_se = kzalloc(sizeof(rt_se) * NR_CPUS, GFP_KERNEL); + if (!tg->rt_se) + goto err; + + tg->shares = NICE_0_LOAD; + tg->rt_ratio = 0; /* XXX */ for_each_possible_cpu(i) { rq = cpu_rq(i); - cfs_rq = kmalloc_node(sizeof(struct cfs_rq), GFP_KERNEL, - cpu_to_node(i)); + cfs_rq = kmalloc_node(sizeof(struct cfs_rq), + GFP_KERNEL|__GFP_ZERO, cpu_to_node(i)); if (!cfs_rq) goto err; - se = kmalloc_node(sizeof(struct sched_entity), GFP_KERNEL, - cpu_to_node(i)); + se = kmalloc_node(sizeof(struct sched_entity), + GFP_KERNEL|__GFP_ZERO, cpu_to_node(i)); if (!se) goto err; - memset(cfs_rq, 0, sizeof(struct cfs_rq)); - memset(se, 0, sizeof(struct sched_entity)); + rt_rq = kmalloc_node(sizeof(struct rt_rq), + GFP_KERNEL|__GFP_ZERO, cpu_to_node(i)); + if (!rt_rq) + goto err; - tg->cfs_rq[i] = cfs_rq; - init_cfs_rq(cfs_rq, rq); - cfs_rq->tg = tg; + rt_se = kmalloc_node(sizeof(struct sched_rt_entity), + GFP_KERNEL|__GFP_ZERO, cpu_to_node(i)); + if (!rt_se) + goto err; - tg->se[i] = se; - se->cfs_rq = &rq->cfs; - se->my_q = cfs_rq; - se->load.weight = NICE_0_LOAD; - se->load.inv_weight = div64_64(1ULL<<32, NICE_0_LOAD); - se->parent = NULL; + init_tg_cfs_entry(rq, tg, cfs_rq, se, i, 0); + init_tg_rt_entry(rq, tg, rt_rq, rt_se, i, 0); } + lock_task_group_list(); for_each_possible_cpu(i) { rq = cpu_rq(i); cfs_rq = tg->cfs_rq[i]; list_add_rcu(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list); + rt_rq = tg->rt_rq[i]; + list_add_rcu(&rt_rq->leaf_rt_rq_list, &rq->leaf_rt_rq_list); } - - tg->shares = NICE_0_LOAD; - spin_lock_init(&tg->lock); + list_add_rcu(&tg->list, &task_groups); + unlock_task_group_list(); return tg; err: - for_each_possible_cpu(i) { - if (tg->cfs_rq) - kfree(tg->cfs_rq[i]); - if (tg->se) - kfree(tg->se[i]); - } - kfree(tg->cfs_rq); - kfree(tg->se); - kfree(tg); - + free_sched_group(tg); return ERR_PTR(-ENOMEM); } /* rcu callback to free various structures associated with a task group */ -static void free_sched_group(struct rcu_head *rhp) +static void free_sched_group_rcu(struct rcu_head *rhp) { - struct task_group *tg = container_of(rhp, struct task_group, rcu); - struct cfs_rq *cfs_rq; - struct sched_entity *se; - int i; - /* now it should be safe to free those cfs_rqs */ - for_each_possible_cpu(i) { - cfs_rq = tg->cfs_rq[i]; - kfree(cfs_rq); - - se = tg->se[i]; - kfree(se); - } - - kfree(tg->cfs_rq); - kfree(tg->se); - kfree(tg); + free_sched_group(container_of(rhp, struct task_group, rcu)); } /* Destroy runqueue etc associated with a task group */ void sched_destroy_group(struct task_group *tg) { struct cfs_rq *cfs_rq = NULL; + struct rt_rq *rt_rq = NULL; int i; + lock_task_group_list(); for_each_possible_cpu(i) { cfs_rq = tg->cfs_rq[i]; list_del_rcu(&cfs_rq->leaf_cfs_rq_list); + rt_rq = tg->rt_rq[i]; + list_del_rcu(&rt_rq->leaf_rt_rq_list); } + list_del_rcu(&tg->list); + unlock_task_group_list(); BUG_ON(!cfs_rq); /* wait for possible concurrent references to cfs_rqs complete */ - call_rcu(&tg->rcu, free_sched_group); + call_rcu(&tg->rcu, free_sched_group_rcu); } /* change task's runqueue when it moves between groups. @@ -7094,14 +7681,9 @@ void sched_move_task(struct task_struct *tsk) rq = task_rq_lock(tsk, &flags); - if (tsk->sched_class != &fair_sched_class) { - set_task_cfs_rq(tsk, task_cpu(tsk)); - goto done; - } - update_rq_clock(rq); - running = task_running(rq, tsk); + running = task_current(rq, tsk); on_rq = tsk->se.on_rq; if (on_rq) { @@ -7110,7 +7692,7 @@ void sched_move_task(struct task_struct *tsk) tsk->sched_class->put_prev_task(rq, tsk); } - set_task_cfs_rq(tsk, task_cpu(tsk)); + set_task_rq(tsk, task_cpu(tsk)); if (on_rq) { if (unlikely(running)) @@ -7118,45 +7700,82 @@ void sched_move_task(struct task_struct *tsk) enqueue_task(rq, tsk, 0); } -done: task_rq_unlock(rq, &flags); } +/* rq->lock to be locked by caller */ static void set_se_shares(struct sched_entity *se, unsigned long shares) { struct cfs_rq *cfs_rq = se->cfs_rq; struct rq *rq = cfs_rq->rq; int on_rq; - spin_lock_irq(&rq->lock); + if (!shares) + shares = MIN_GROUP_SHARES; on_rq = se->on_rq; - if (on_rq) + if (on_rq) { dequeue_entity(cfs_rq, se, 0); + dec_cpu_load(rq, se->load.weight); + } se->load.weight = shares; se->load.inv_weight = div64_64((1ULL<<32), shares); - if (on_rq) + if (on_rq) { enqueue_entity(cfs_rq, se, 0); - - spin_unlock_irq(&rq->lock); + inc_cpu_load(rq, se->load.weight); + } } int sched_group_set_shares(struct task_group *tg, unsigned long shares) { int i; + struct cfs_rq *cfs_rq; + struct rq *rq; - spin_lock(&tg->lock); + lock_task_group_list(); if (tg->shares == shares) goto done; + if (shares < MIN_GROUP_SHARES) + shares = MIN_GROUP_SHARES; + + /* + * Prevent any load balance activity (rebalance_shares, + * load_balance_fair) from referring to this group first, + * by taking it off the rq->leaf_cfs_rq_list on each cpu. + */ + for_each_possible_cpu(i) { + cfs_rq = tg->cfs_rq[i]; + list_del_rcu(&cfs_rq->leaf_cfs_rq_list); + } + + /* wait for any ongoing reference to this group to finish */ + synchronize_sched(); + + /* + * Now we are free to modify the group's share on each cpu + * w/o tripping rebalance_share or load_balance_fair. + */ tg->shares = shares; - for_each_possible_cpu(i) + for_each_possible_cpu(i) { + spin_lock_irq(&cpu_rq(i)->lock); set_se_shares(tg->se[i], shares); + spin_unlock_irq(&cpu_rq(i)->lock); + } + /* + * Enable load balance activity on this group, by inserting it back on + * each cpu's rq->leaf_cfs_rq_list. + */ + for_each_possible_cpu(i) { + rq = cpu_rq(i); + cfs_rq = tg->cfs_rq[i]; + list_add_rcu(&cfs_rq->leaf_cfs_rq_list, &rq->leaf_cfs_rq_list); + } done: - spin_unlock(&tg->lock); + unlock_task_group_list(); return 0; } @@ -7165,6 +7784,31 @@ unsigned long sched_group_shares(struct task_group *tg) return tg->shares; } +/* + * Ensure the total rt_ratio <= sysctl_sched_rt_ratio + */ +int sched_group_set_rt_ratio(struct task_group *tg, unsigned long rt_ratio) +{ + struct task_group *tgi; + unsigned long total = 0; + + rcu_read_lock(); + list_for_each_entry_rcu(tgi, &task_groups, list) + total += tgi->rt_ratio; + rcu_read_unlock(); + + if (total + rt_ratio - tg->rt_ratio > sysctl_sched_rt_ratio) + return -EINVAL; + + tg->rt_ratio = rt_ratio; + return 0; +} + +unsigned long sched_group_rt_ratio(struct task_group *tg) +{ + return tg->rt_ratio; +} + #endif /* CONFIG_FAIR_GROUP_SCHED */ #ifdef CONFIG_FAIR_CGROUP_SCHED @@ -7240,12 +7884,30 @@ static u64 cpu_shares_read_uint(struct cgroup *cgrp, struct cftype *cft) return (u64) tg->shares; } +static int cpu_rt_ratio_write_uint(struct cgroup *cgrp, struct cftype *cftype, + u64 rt_ratio_val) +{ + return sched_group_set_rt_ratio(cgroup_tg(cgrp), rt_ratio_val); +} + +static u64 cpu_rt_ratio_read_uint(struct cgroup *cgrp, struct cftype *cft) +{ + struct task_group *tg = cgroup_tg(cgrp); + + return (u64) tg->rt_ratio; +} + static struct cftype cpu_files[] = { { .name = "shares", .read_uint = cpu_shares_read_uint, .write_uint = cpu_shares_write_uint, }, + { + .name = "rt_ratio", + .read_uint = cpu_rt_ratio_read_uint, + .write_uint = cpu_rt_ratio_write_uint, + }, }; static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont) diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c index d30467b47dd..4b5e24cf2f4 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched_debug.c @@ -31,9 +31,9 @@ /* * Ease the printing of nsec fields: */ -static long long nsec_high(long long nsec) +static long long nsec_high(unsigned long long nsec) { - if (nsec < 0) { + if ((long long)nsec < 0) { nsec = -nsec; do_div(nsec, 1000000); return -nsec; @@ -43,9 +43,9 @@ static long long nsec_high(long long nsec) return nsec; } -static unsigned long nsec_low(long long nsec) +static unsigned long nsec_low(unsigned long long nsec) { - if (nsec < 0) + if ((long long)nsec < 0) nsec = -nsec; return do_div(nsec, 1000000); @@ -179,6 +179,7 @@ static void print_cpu(struct seq_file *m, int cpu) PN(prev_clock_raw); P(clock_warps); P(clock_overflows); + P(clock_underflows); P(clock_deep_idle_events); PN(clock_max_delta); P(cpu_load[0]); @@ -299,6 +300,8 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m) PN(se.exec_max); PN(se.slice_max); PN(se.wait_max); + PN(se.wait_sum); + P(se.wait_count); P(sched_info.bkl_count); P(se.nr_migrations); P(se.nr_migrations_cold); @@ -366,6 +369,8 @@ void proc_sched_set_task(struct task_struct *p) { #ifdef CONFIG_SCHEDSTATS p->se.wait_max = 0; + p->se.wait_sum = 0; + p->se.wait_count = 0; p->se.sleep_max = 0; p->se.sum_sleep_runtime = 0; p->se.block_max = 0; diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index c33f0ceb3de..6c091d6e159 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -20,6 +20,8 @@ * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com> */ +#include <linux/latencytop.h> + /* * Targeted preemption latency for CPU-bound tasks: * (default: 20ms * (1 + ilog(ncpus)), units: nanoseconds) @@ -248,8 +250,8 @@ static u64 __sched_period(unsigned long nr_running) unsigned long nr_latency = sched_nr_latency; if (unlikely(nr_running > nr_latency)) { + period = sysctl_sched_min_granularity; period *= nr_running; - do_div(period, nr_latency); } return period; @@ -383,6 +385,9 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se) { schedstat_set(se->wait_max, max(se->wait_max, rq_of(cfs_rq)->clock - se->wait_start)); + schedstat_set(se->wait_count, se->wait_count + 1); + schedstat_set(se->wait_sum, se->wait_sum + + rq_of(cfs_rq)->clock - se->wait_start); schedstat_set(se->wait_start, 0); } @@ -434,6 +439,7 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) #ifdef CONFIG_SCHEDSTATS if (se->sleep_start) { u64 delta = rq_of(cfs_rq)->clock - se->sleep_start; + struct task_struct *tsk = task_of(se); if ((s64)delta < 0) delta = 0; @@ -443,9 +449,12 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) se->sleep_start = 0; se->sum_sleep_runtime += delta; + + account_scheduler_latency(tsk, delta >> 10, 1); } if (se->block_start) { u64 delta = rq_of(cfs_rq)->clock - se->block_start; + struct task_struct *tsk = task_of(se); if ((s64)delta < 0) delta = 0; @@ -462,11 +471,11 @@ static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se) * time that the task spent sleeping: */ if (unlikely(prof_on == SLEEP_PROFILING)) { - struct task_struct *tsk = task_of(se); profile_hits(SLEEP_PROFILING, (void *)get_wchan(tsk), delta >> 20); } + account_scheduler_latency(tsk, delta >> 10, 0); } #endif } @@ -511,8 +520,7 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial) if (!initial) { /* sleeps upto a single latency don't count. */ - if (sched_feat(NEW_FAIR_SLEEPERS) && entity_is_task(se) && - task_of(se)->policy != SCHED_BATCH) + if (sched_feat(NEW_FAIR_SLEEPERS)) vruntime -= sysctl_sched_latency; /* ensure we never gain time by being placed backwards. */ @@ -643,13 +651,29 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev) cfs_rq->curr = NULL; } -static void entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr) +static void +entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued) { /* * Update run-time statistics of the 'current'. */ update_curr(cfs_rq); +#ifdef CONFIG_SCHED_HRTICK + /* + * queued ticks are scheduled to match the slice, so don't bother + * validating it and just reschedule. + */ + if (queued) + return resched_task(rq_of(cfs_rq)->curr); + /* + * don't let the period tick interfere with the hrtick preemption + */ + if (!sched_feat(DOUBLE_TICK) && + hrtimer_active(&rq_of(cfs_rq)->hrtick_timer)) + return; +#endif + if (cfs_rq->nr_running > 1 || !sched_feat(WAKEUP_PREEMPT)) check_preempt_tick(cfs_rq, curr); } @@ -691,7 +715,7 @@ static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu) /* Iterate thr' all leaf cfs_rq's on a runqueue */ #define for_each_leaf_cfs_rq(rq, cfs_rq) \ - list_for_each_entry(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list) + list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list) /* Do the two (enqueued) entities belong to the same group ? */ static inline int @@ -708,6 +732,8 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se) return se->parent; } +#define GROUP_IMBALANCE_PCT 20 + #else /* CONFIG_FAIR_GROUP_SCHED */ #define for_each_sched_entity(se) \ @@ -753,6 +779,43 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se) #endif /* CONFIG_FAIR_GROUP_SCHED */ +#ifdef CONFIG_SCHED_HRTICK +static void hrtick_start_fair(struct rq *rq, struct task_struct *p) +{ + int requeue = rq->curr == p; + struct sched_entity *se = &p->se; + struct cfs_rq *cfs_rq = cfs_rq_of(se); + + WARN_ON(task_rq(p) != rq); + + if (hrtick_enabled(rq) && cfs_rq->nr_running > 1) { + u64 slice = sched_slice(cfs_rq, se); + u64 ran = se->sum_exec_runtime - se->prev_sum_exec_runtime; + s64 delta = slice - ran; + + if (delta < 0) { + if (rq->curr == p) + resched_task(p); + return; + } + + /* + * Don't schedule slices shorter than 10000ns, that just + * doesn't make sense. Rely on vruntime for fairness. + */ + if (!requeue) + delta = max(10000LL, delta); + + hrtick_start(rq, delta, requeue); + } +} +#else +static inline void +hrtick_start_fair(struct rq *rq, struct task_struct *p) +{ +} +#endif + /* * The enqueue_task method is called before nr_running is * increased. Here we update the fair scheduling stats and @@ -761,15 +824,28 @@ static inline struct sched_entity *parent_entity(struct sched_entity *se) static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup) { struct cfs_rq *cfs_rq; - struct sched_entity *se = &p->se; + struct sched_entity *se = &p->se, + *topse = NULL; /* Highest schedulable entity */ + int incload = 1; for_each_sched_entity(se) { - if (se->on_rq) + topse = se; + if (se->on_rq) { + incload = 0; break; + } cfs_rq = cfs_rq_of(se); enqueue_entity(cfs_rq, se, wakeup); wakeup = 1; } + /* Increment cpu load if we just enqueued the first task of a group on + * 'rq->cpu'. 'topse' represents the group to which task 'p' belongs + * at the highest grouping level. + */ + if (incload) + inc_cpu_load(rq, topse->load.weight); + + hrtick_start_fair(rq, rq->curr); } /* @@ -780,16 +856,30 @@ static void enqueue_task_fair(struct rq *rq, struct task_struct *p, int wakeup) static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int sleep) { struct cfs_rq *cfs_rq; - struct sched_entity *se = &p->se; + struct sched_entity *se = &p->se, + *topse = NULL; /* Highest schedulable entity */ + int decload = 1; for_each_sched_entity(se) { + topse = se; cfs_rq = cfs_rq_of(se); dequeue_entity(cfs_rq, se, sleep); /* Don't dequeue parent if it has other entities besides us */ - if (cfs_rq->load.weight) + if (cfs_rq->load.weight) { + if (parent_entity(se)) + decload = 0; break; + } sleep = 1; } + /* Decrement cpu load if we just dequeued the last task of a group on + * 'rq->cpu'. 'topse' represents the group to which task 'p' belongs + * at the highest grouping level. + */ + if (decload) + dec_cpu_load(rq, topse->load.weight); + + hrtick_start_fair(rq, rq->curr); } /* @@ -837,6 +927,154 @@ static void yield_task_fair(struct rq *rq) } /* + * wake_idle() will wake a task on an idle cpu if task->cpu is + * not idle and an idle cpu is available. The span of cpus to + * search starts with cpus closest then further out as needed, + * so we always favor a closer, idle cpu. + * + * Returns the CPU we should wake onto. + */ +#if defined(ARCH_HAS_SCHED_WAKE_IDLE) +static int wake_idle(int cpu, struct task_struct *p) +{ + cpumask_t tmp; + struct sched_domain *sd; + int i; + + /* + * If it is idle, then it is the best cpu to run this task. + * + * This cpu is also the best, if it has more than one task already. + * Siblings must be also busy(in most cases) as they didn't already + * pickup the extra load from this cpu and hence we need not check + * sibling runqueue info. This will avoid the checks and cache miss + * penalities associated with that. + */ + if (idle_cpu(cpu) || cpu_rq(cpu)->nr_running > 1) + return cpu; + + for_each_domain(cpu, sd) { + if (sd->flags & SD_WAKE_IDLE) { + cpus_and(tmp, sd->span, p->cpus_allowed); + for_each_cpu_mask(i, tmp) { + if (idle_cpu(i)) { + if (i != task_cpu(p)) { + schedstat_inc(p, + se.nr_wakeups_idle); + } + return i; + } + } + } else { + break; + } + } + return cpu; +} +#else +static inline int wake_idle(int cpu, struct task_struct *p) +{ + return cpu; +} +#endif + +#ifdef CONFIG_SMP +static int select_task_rq_fair(struct task_struct *p, int sync) +{ + int cpu, this_cpu; + struct rq *rq; + struct sched_domain *sd, *this_sd = NULL; + int new_cpu; + + cpu = task_cpu(p); + rq = task_rq(p); + this_cpu = smp_processor_id(); + new_cpu = cpu; + + if (cpu == this_cpu) + goto out_set_cpu; + + for_each_domain(this_cpu, sd) { + if (cpu_isset(cpu, sd->span)) { + this_sd = sd; + break; + } + } + + if (unlikely(!cpu_isset(this_cpu, p->cpus_allowed))) + goto out_set_cpu; + + /* + * Check for affine wakeup and passive balancing possibilities. + */ + if (this_sd) { + int idx = this_sd->wake_idx; + unsigned int imbalance; + unsigned long load, this_load; + + imbalance = 100 + (this_sd->imbalance_pct - 100) / 2; + + load = source_load(cpu, idx); + this_load = target_load(this_cpu, idx); + + new_cpu = this_cpu; /* Wake to this CPU if we can */ + + if (this_sd->flags & SD_WAKE_AFFINE) { + unsigned long tl = this_load; + unsigned long tl_per_task; + + /* + * Attract cache-cold tasks on sync wakeups: + */ + if (sync && !task_hot(p, rq->clock, this_sd)) + goto out_set_cpu; + + schedstat_inc(p, se.nr_wakeups_affine_attempts); + tl_per_task = cpu_avg_load_per_task(this_cpu); + + /* + * If sync wakeup then subtract the (maximum possible) + * effect of the currently running task from the load + * of the current CPU: + */ + if (sync) + tl -= current->se.load.weight; + + if ((tl <= load && + tl + target_load(cpu, idx) <= tl_per_task) || + 100*(tl + p->se.load.weight) <= imbalance*load) { + /* + * This domain has SD_WAKE_AFFINE and + * p is cache cold in this domain, and + * there is no bad imbalance. + */ + schedstat_inc(this_sd, ttwu_move_affine); + schedstat_inc(p, se.nr_wakeups_affine); + goto out_set_cpu; + } + } + + /* + * Start passive balancing when half the imbalance_pct + * limit is reached. + */ + if (this_sd->flags & SD_WAKE_BALANCE) { + if (imbalance*this_load <= 100*load) { + schedstat_inc(this_sd, ttwu_move_balance); + schedstat_inc(p, se.nr_wakeups_passive); + goto out_set_cpu; + } + } + } + + new_cpu = cpu; /* Could not wake to this_cpu. Wake to cpu instead */ +out_set_cpu: + return wake_idle(new_cpu, p); +} +#endif /* CONFIG_SMP */ + + +/* * Preempt the current task with a newly woken task if needed: */ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p) @@ -868,7 +1106,11 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p) } gran = sysctl_sched_wakeup_granularity; - if (unlikely(se->load.weight != NICE_0_LOAD)) + /* + * More easily preempt - nice tasks, while not making + * it harder for + nice tasks. + */ + if (unlikely(se->load.weight > NICE_0_LOAD)) gran = calc_delta_fair(gran, &se->load); if (pse->vruntime + gran < se->vruntime) @@ -877,6 +1119,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p) static struct task_struct *pick_next_task_fair(struct rq *rq) { + struct task_struct *p; struct cfs_rq *cfs_rq = &rq->cfs; struct sched_entity *se; @@ -888,7 +1131,10 @@ static struct task_struct *pick_next_task_fair(struct rq *rq) cfs_rq = group_cfs_rq(se); } while (cfs_rq); - return task_of(se); + p = task_of(se); + hrtick_start_fair(rq, p); + + return p; } /* @@ -945,25 +1191,6 @@ static struct task_struct *load_balance_next_fair(void *arg) return __load_balance_iterator(cfs_rq, cfs_rq->rb_load_balance_curr); } -#ifdef CONFIG_FAIR_GROUP_SCHED -static int cfs_rq_best_prio(struct cfs_rq *cfs_rq) -{ - struct sched_entity *curr; - struct task_struct *p; - - if (!cfs_rq->nr_running) - return MAX_PRIO; - - curr = cfs_rq->curr; - if (!curr) - curr = __pick_next_entity(cfs_rq); - - p = task_of(curr); - - return p->prio; -} -#endif - static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_load_move, @@ -973,28 +1200,45 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, struct cfs_rq *busy_cfs_rq; long rem_load_move = max_load_move; struct rq_iterator cfs_rq_iterator; + unsigned long load_moved; cfs_rq_iterator.start = load_balance_start_fair; cfs_rq_iterator.next = load_balance_next_fair; for_each_leaf_cfs_rq(busiest, busy_cfs_rq) { #ifdef CONFIG_FAIR_GROUP_SCHED - struct cfs_rq *this_cfs_rq; - long imbalance; - unsigned long maxload; + struct cfs_rq *this_cfs_rq = busy_cfs_rq->tg->cfs_rq[this_cpu]; + unsigned long maxload, task_load, group_weight; + unsigned long thisload, per_task_load; + struct sched_entity *se = busy_cfs_rq->tg->se[busiest->cpu]; + + task_load = busy_cfs_rq->load.weight; + group_weight = se->load.weight; - this_cfs_rq = cpu_cfs_rq(busy_cfs_rq, this_cpu); + /* + * 'group_weight' is contributed by tasks of total weight + * 'task_load'. To move 'rem_load_move' worth of weight only, + * we need to move a maximum task load of: + * + * maxload = (remload / group_weight) * task_load; + */ + maxload = (rem_load_move * task_load) / group_weight; - imbalance = busy_cfs_rq->load.weight - this_cfs_rq->load.weight; - /* Don't pull if this_cfs_rq has more load than busy_cfs_rq */ - if (imbalance <= 0) + if (!maxload || !task_load) continue; - /* Don't pull more than imbalance/2 */ - imbalance /= 2; - maxload = min(rem_load_move, imbalance); + per_task_load = task_load / busy_cfs_rq->nr_running; + /* + * balance_tasks will try to forcibly move atleast one task if + * possible (because of SCHED_LOAD_SCALE_FUZZ). Avoid that if + * maxload is less than GROUP_IMBALANCE_FUZZ% the per_task_load. + */ + if (100 * maxload < GROUP_IMBALANCE_PCT * per_task_load) + continue; - *this_best_prio = cfs_rq_best_prio(this_cfs_rq); + /* Disable priority-based load balance */ + *this_best_prio = 0; + thisload = this_cfs_rq->load.weight; #else # define maxload rem_load_move #endif @@ -1003,11 +1247,33 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, * load_balance_[start|next]_fair iterators */ cfs_rq_iterator.arg = busy_cfs_rq; - rem_load_move -= balance_tasks(this_rq, this_cpu, busiest, + load_moved = balance_tasks(this_rq, this_cpu, busiest, maxload, sd, idle, all_pinned, this_best_prio, &cfs_rq_iterator); +#ifdef CONFIG_FAIR_GROUP_SCHED + /* + * load_moved holds the task load that was moved. The + * effective (group) weight moved would be: + * load_moved_eff = load_moved/task_load * group_weight; + */ + load_moved = (group_weight * load_moved) / task_load; + + /* Adjust shares on both cpus to reflect load_moved */ + group_weight -= load_moved; + set_se_shares(se, group_weight); + + se = busy_cfs_rq->tg->se[this_cpu]; + if (!thisload) + group_weight = load_moved; + else + group_weight = se->load.weight + load_moved; + set_se_shares(se, group_weight); +#endif + + rem_load_move -= load_moved; + if (rem_load_move <= 0) break; } @@ -1043,14 +1309,14 @@ move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, /* * scheduler tick hitting a task of our scheduling class: */ -static void task_tick_fair(struct rq *rq, struct task_struct *curr) +static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) { struct cfs_rq *cfs_rq; struct sched_entity *se = &curr->se; for_each_sched_entity(se) { cfs_rq = cfs_rq_of(se); - entity_tick(cfs_rq, se); + entity_tick(cfs_rq, se, queued); } } @@ -1088,6 +1354,42 @@ static void task_new_fair(struct rq *rq, struct task_struct *p) resched_task(rq->curr); } +/* + * Priority of the task has changed. Check to see if we preempt + * the current task. + */ +static void prio_changed_fair(struct rq *rq, struct task_struct *p, + int oldprio, int running) +{ + /* + * Reschedule if we are currently running on this runqueue and + * our priority decreased, or if we are not currently running on + * this runqueue and our priority is higher than the current's + */ + if (running) { + if (p->prio > oldprio) + resched_task(rq->curr); + } else + check_preempt_curr(rq, p); +} + +/* + * We switched to the sched_fair class. + */ +static void switched_to_fair(struct rq *rq, struct task_struct *p, + int running) +{ + /* + * We were most likely switched from sched_rt, so + * kick off the schedule if running, otherwise just see + * if we can still preempt the current task. + */ + if (running) + resched_task(rq->curr); + else + check_preempt_curr(rq, p); +} + /* Account for a task changing its policy or group. * * This routine is mostly called to set cfs_rq->curr field when a task @@ -1109,6 +1411,9 @@ static const struct sched_class fair_sched_class = { .enqueue_task = enqueue_task_fair, .dequeue_task = dequeue_task_fair, .yield_task = yield_task_fair, +#ifdef CONFIG_SMP + .select_task_rq = select_task_rq_fair, +#endif /* CONFIG_SMP */ .check_preempt_curr = check_preempt_wakeup, @@ -1123,6 +1428,9 @@ static const struct sched_class fair_sched_class = { .set_curr_task = set_curr_task_fair, .task_tick = task_tick_fair, .task_new = task_new_fair, + + .prio_changed = prio_changed_fair, + .switched_to = switched_to_fair, }; #ifdef CONFIG_SCHED_DEBUG @@ -1133,7 +1441,9 @@ static void print_cfs_stats(struct seq_file *m, int cpu) #ifdef CONFIG_FAIR_GROUP_SCHED print_cfs_rq(m, cpu, &cpu_rq(cpu)->cfs); #endif + rcu_read_lock(); for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq) print_cfs_rq(m, cpu, cfs_rq); + rcu_read_unlock(); } #endif diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c index bf9c25c15b8..2bcafa37563 100644 --- a/kernel/sched_idletask.c +++ b/kernel/sched_idletask.c @@ -5,6 +5,12 @@ * handled in sched_fair.c) */ +#ifdef CONFIG_SMP +static int select_task_rq_idle(struct task_struct *p, int sync) +{ + return task_cpu(p); /* IDLE tasks as never migrated */ +} +#endif /* CONFIG_SMP */ /* * Idle tasks are unconditionally rescheduled: */ @@ -55,7 +61,7 @@ move_one_task_idle(struct rq *this_rq, int this_cpu, struct rq *busiest, } #endif -static void task_tick_idle(struct rq *rq, struct task_struct *curr) +static void task_tick_idle(struct rq *rq, struct task_struct *curr, int queued) { } @@ -63,6 +69,33 @@ static void set_curr_task_idle(struct rq *rq) { } +static void switched_to_idle(struct rq *rq, struct task_struct *p, + int running) +{ + /* Can this actually happen?? */ + if (running) + resched_task(rq->curr); + else + check_preempt_curr(rq, p); +} + +static void prio_changed_idle(struct rq *rq, struct task_struct *p, + int oldprio, int running) +{ + /* This can happen for hot plug CPUS */ + + /* + * Reschedule if we are currently running on this runqueue and + * our priority decreased, or if we are not currently running on + * this runqueue and our priority is higher than the current's + */ + if (running) { + if (p->prio > oldprio) + resched_task(rq->curr); + } else + check_preempt_curr(rq, p); +} + /* * Simple, special scheduling class for the per-CPU idle tasks: */ @@ -72,6 +105,9 @@ const struct sched_class idle_sched_class = { /* dequeue is not valid, we print a debug message there: */ .dequeue_task = dequeue_task_idle, +#ifdef CONFIG_SMP + .select_task_rq = select_task_rq_idle, +#endif /* CONFIG_SMP */ .check_preempt_curr = check_preempt_curr_idle, @@ -85,5 +121,9 @@ const struct sched_class idle_sched_class = { .set_curr_task = set_curr_task_idle, .task_tick = task_tick_idle, + + .prio_changed = prio_changed_idle, + .switched_to = switched_to_idle, + /* no .task_new for idle tasks */ }; diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index ee9c8b6529e..274b40d7bef 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -3,6 +3,217 @@ * policies) */ +#ifdef CONFIG_SMP + +static inline int rt_overloaded(struct rq *rq) +{ + return atomic_read(&rq->rd->rto_count); +} + +static inline void rt_set_overload(struct rq *rq) +{ + cpu_set(rq->cpu, rq->rd->rto_mask); + /* + * Make sure the mask is visible before we set + * the overload count. That is checked to determine + * if we should look at the mask. It would be a shame + * if we looked at the mask, but the mask was not + * updated yet. + */ + wmb(); + atomic_inc(&rq->rd->rto_count); +} + +static inline void rt_clear_overload(struct rq *rq) +{ + /* the order here really doesn't matter */ + atomic_dec(&rq->rd->rto_count); + cpu_clear(rq->cpu, rq->rd->rto_mask); +} + +static void update_rt_migration(struct rq *rq) +{ + if (rq->rt.rt_nr_migratory && (rq->rt.rt_nr_running > 1)) { + if (!rq->rt.overloaded) { + rt_set_overload(rq); + rq->rt.overloaded = 1; + } + } else if (rq->rt.overloaded) { + rt_clear_overload(rq); + rq->rt.overloaded = 0; + } +} +#endif /* CONFIG_SMP */ + +static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se) +{ + return container_of(rt_se, struct task_struct, rt); +} + +static inline int on_rt_rq(struct sched_rt_entity *rt_se) +{ + return !list_empty(&rt_se->run_list); +} + +#ifdef CONFIG_FAIR_GROUP_SCHED + +static inline unsigned int sched_rt_ratio(struct rt_rq *rt_rq) +{ + if (!rt_rq->tg) + return SCHED_RT_FRAC; + + return rt_rq->tg->rt_ratio; +} + +#define for_each_leaf_rt_rq(rt_rq, rq) \ + list_for_each_entry(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list) + +static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq) +{ + return rt_rq->rq; +} + +static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se) +{ + return rt_se->rt_rq; +} + +#define for_each_sched_rt_entity(rt_se) \ + for (; rt_se; rt_se = rt_se->parent) + +static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se) +{ + return rt_se->my_q; +} + +static void enqueue_rt_entity(struct sched_rt_entity *rt_se); +static void dequeue_rt_entity(struct sched_rt_entity *rt_se); + +static void sched_rt_ratio_enqueue(struct rt_rq *rt_rq) +{ + struct sched_rt_entity *rt_se = rt_rq->rt_se; + + if (rt_se && !on_rt_rq(rt_se) && rt_rq->rt_nr_running) { + struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr; + + enqueue_rt_entity(rt_se); + if (rt_rq->highest_prio < curr->prio) + resched_task(curr); + } +} + +static void sched_rt_ratio_dequeue(struct rt_rq *rt_rq) +{ + struct sched_rt_entity *rt_se = rt_rq->rt_se; + + if (rt_se && on_rt_rq(rt_se)) + dequeue_rt_entity(rt_se); +} + +#else + +static inline unsigned int sched_rt_ratio(struct rt_rq *rt_rq) +{ + return sysctl_sched_rt_ratio; +} + +#define for_each_leaf_rt_rq(rt_rq, rq) \ + for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL) + +static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq) +{ + return container_of(rt_rq, struct rq, rt); +} + +static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se) +{ + struct task_struct *p = rt_task_of(rt_se); + struct rq *rq = task_rq(p); + + return &rq->rt; +} + +#define for_each_sched_rt_entity(rt_se) \ + for (; rt_se; rt_se = NULL) + +static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se) +{ + return NULL; +} + +static inline void sched_rt_ratio_enqueue(struct rt_rq *rt_rq) +{ +} + +static inline void sched_rt_ratio_dequeue(struct rt_rq *rt_rq) +{ +} + +#endif + +static inline int rt_se_prio(struct sched_rt_entity *rt_se) +{ +#ifdef CONFIG_FAIR_GROUP_SCHED + struct rt_rq *rt_rq = group_rt_rq(rt_se); + + if (rt_rq) + return rt_rq->highest_prio; +#endif + + return rt_task_of(rt_se)->prio; +} + +static int sched_rt_ratio_exceeded(struct rt_rq *rt_rq) +{ + unsigned int rt_ratio = sched_rt_ratio(rt_rq); + u64 period, ratio; + + if (rt_ratio == SCHED_RT_FRAC) + return 0; + + if (rt_rq->rt_throttled) + return 1; + + period = (u64)sysctl_sched_rt_period * NSEC_PER_MSEC; + ratio = (period * rt_ratio) >> SCHED_RT_FRAC_SHIFT; + + if (rt_rq->rt_time > ratio) { + struct rq *rq = rq_of_rt_rq(rt_rq); + + rq->rt_throttled = 1; + rt_rq->rt_throttled = 1; + + sched_rt_ratio_dequeue(rt_rq); + return 1; + } + + return 0; +} + +static void update_sched_rt_period(struct rq *rq) +{ + struct rt_rq *rt_rq; + u64 period; + + while (rq->clock > rq->rt_period_expire) { + period = (u64)sysctl_sched_rt_period * NSEC_PER_MSEC; + rq->rt_period_expire += period; + + for_each_leaf_rt_rq(rt_rq, rq) { + unsigned long rt_ratio = sched_rt_ratio(rt_rq); + u64 ratio = (period * rt_ratio) >> SCHED_RT_FRAC_SHIFT; + + rt_rq->rt_time -= min(rt_rq->rt_time, ratio); + if (rt_rq->rt_throttled) { + rt_rq->rt_throttled = 0; + sched_rt_ratio_enqueue(rt_rq); + } + } + + rq->rt_throttled = 0; + } +} + /* * Update the current task's runtime statistics. Skip current tasks that * are not in our scheduling class. @@ -10,6 +221,8 @@ static void update_curr_rt(struct rq *rq) { struct task_struct *curr = rq->curr; + struct sched_rt_entity *rt_se = &curr->rt; + struct rt_rq *rt_rq = rt_rq_of_se(rt_se); u64 delta_exec; if (!task_has_rt_policy(curr)) @@ -24,47 +237,228 @@ static void update_curr_rt(struct rq *rq) curr->se.sum_exec_runtime += delta_exec; curr->se.exec_start = rq->clock; cpuacct_charge(curr, delta_exec); + + rt_rq->rt_time += delta_exec; + /* + * might make it a tad more accurate: + * + * update_sched_rt_period(rq); + */ + if (sched_rt_ratio_exceeded(rt_rq)) + resched_task(curr); } -static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup) +static inline +void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) +{ + WARN_ON(!rt_prio(rt_se_prio(rt_se))); + rt_rq->rt_nr_running++; +#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED + if (rt_se_prio(rt_se) < rt_rq->highest_prio) + rt_rq->highest_prio = rt_se_prio(rt_se); +#endif +#ifdef CONFIG_SMP + if (rt_se->nr_cpus_allowed > 1) { + struct rq *rq = rq_of_rt_rq(rt_rq); + rq->rt.rt_nr_migratory++; + } + + update_rt_migration(rq_of_rt_rq(rt_rq)); +#endif +} + +static inline +void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) +{ + WARN_ON(!rt_prio(rt_se_prio(rt_se))); + WARN_ON(!rt_rq->rt_nr_running); + rt_rq->rt_nr_running--; +#if defined CONFIG_SMP || defined CONFIG_FAIR_GROUP_SCHED + if (rt_rq->rt_nr_running) { + struct rt_prio_array *array; + + WARN_ON(rt_se_prio(rt_se) < rt_rq->highest_prio); + if (rt_se_prio(rt_se) == rt_rq->highest_prio) { + /* recalculate */ + array = &rt_rq->active; + rt_rq->highest_prio = + sched_find_first_bit(array->bitmap); + } /* otherwise leave rq->highest prio alone */ + } else + rt_rq->highest_prio = MAX_RT_PRIO; +#endif +#ifdef CONFIG_SMP + if (rt_se->nr_cpus_allowed > 1) { + struct rq *rq = rq_of_rt_rq(rt_rq); + rq->rt.rt_nr_migratory--; + } + + update_rt_migration(rq_of_rt_rq(rt_rq)); +#endif /* CONFIG_SMP */ +} + +static void enqueue_rt_entity(struct sched_rt_entity *rt_se) +{ + struct rt_rq *rt_rq = rt_rq_of_se(rt_se); + struct rt_prio_array *array = &rt_rq->active; + struct rt_rq *group_rq = group_rt_rq(rt_se); + + if (group_rq && group_rq->rt_throttled) + return; + + list_add_tail(&rt_se->run_list, array->queue + rt_se_prio(rt_se)); + __set_bit(rt_se_prio(rt_se), array->bitmap); + + inc_rt_tasks(rt_se, rt_rq); +} + +static void dequeue_rt_entity(struct sched_rt_entity *rt_se) +{ + struct rt_rq *rt_rq = rt_rq_of_se(rt_se); + struct rt_prio_array *array = &rt_rq->active; + + list_del_init(&rt_se->run_list); + if (list_empty(array->queue + rt_se_prio(rt_se))) + __clear_bit(rt_se_prio(rt_se), array->bitmap); + + dec_rt_tasks(rt_se, rt_rq); +} + +/* + * Because the prio of an upper entry depends on the lower + * entries, we must remove entries top - down. + * + * XXX: O(1/2 h^2) because we can only walk up, not down the chain. + * doesn't matter much for now, as h=2 for GROUP_SCHED. + */ +static void dequeue_rt_stack(struct task_struct *p) { - struct rt_prio_array *array = &rq->rt.active; + struct sched_rt_entity *rt_se, *top_se; - list_add_tail(&p->run_list, array->queue + p->prio); - __set_bit(p->prio, array->bitmap); + /* + * dequeue all, top - down. + */ + do { + rt_se = &p->rt; + top_se = NULL; + for_each_sched_rt_entity(rt_se) { + if (on_rt_rq(rt_se)) + top_se = rt_se; + } + if (top_se) + dequeue_rt_entity(top_se); + } while (top_se); } /* * Adding/removing a task to/from a priority array: */ +static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup) +{ + struct sched_rt_entity *rt_se = &p->rt; + + if (wakeup) + rt_se->timeout = 0; + + dequeue_rt_stack(p); + + /* + * enqueue everybody, bottom - up. + */ + for_each_sched_rt_entity(rt_se) + enqueue_rt_entity(rt_se); + + inc_cpu_load(rq, p->se.load.weight); +} + static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep) { - struct rt_prio_array *array = &rq->rt.active; + struct sched_rt_entity *rt_se = &p->rt; + struct rt_rq *rt_rq; update_curr_rt(rq); - list_del(&p->run_list); - if (list_empty(array->queue + p->prio)) - __clear_bit(p->prio, array->bitmap); + dequeue_rt_stack(p); + + /* + * re-enqueue all non-empty rt_rq entities. + */ + for_each_sched_rt_entity(rt_se) { + rt_rq = group_rt_rq(rt_se); + if (rt_rq && rt_rq->rt_nr_running) + enqueue_rt_entity(rt_se); + } + + dec_cpu_load(rq, p->se.load.weight); } /* * Put task to the end of the run list without the overhead of dequeue * followed by enqueue. */ +static +void requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se) +{ + struct rt_prio_array *array = &rt_rq->active; + + list_move_tail(&rt_se->run_list, array->queue + rt_se_prio(rt_se)); +} + static void requeue_task_rt(struct rq *rq, struct task_struct *p) { - struct rt_prio_array *array = &rq->rt.active; + struct sched_rt_entity *rt_se = &p->rt; + struct rt_rq *rt_rq; - list_move_tail(&p->run_list, array->queue + p->prio); + for_each_sched_rt_entity(rt_se) { + rt_rq = rt_rq_of_se(rt_se); + requeue_rt_entity(rt_rq, rt_se); + } } -static void -yield_task_rt(struct rq *rq) +static void yield_task_rt(struct rq *rq) { requeue_task_rt(rq, rq->curr); } +#ifdef CONFIG_SMP +static int find_lowest_rq(struct task_struct *task); + +static int select_task_rq_rt(struct task_struct *p, int sync) +{ + struct rq *rq = task_rq(p); + + /* + * If the current task is an RT task, then + * try to see if we can wake this RT task up on another + * runqueue. Otherwise simply start this RT task + * on its current runqueue. + * + * We want to avoid overloading runqueues. Even if + * the RT task is of higher priority than the current RT task. + * RT tasks behave differently than other tasks. If + * one gets preempted, we try to push it off to another queue. + * So trying to keep a preempting RT task on the same + * cache hot CPU will force the running RT task to + * a cold CPU. So we waste all the cache for the lower + * RT task in hopes of saving some of a RT task + * that is just being woken and probably will have + * cold cache anyway. + */ + if (unlikely(rt_task(rq->curr)) && + (p->rt.nr_cpus_allowed > 1)) { + int cpu = find_lowest_rq(p); + + return (cpu == -1) ? task_cpu(p) : cpu; + } + + /* + * Otherwise, just let it ride on the affined RQ and the + * post-schedule router will push the preempted task away + */ + return task_cpu(p); +} +#endif /* CONFIG_SMP */ + /* * Preempt the current task with a newly woken task if needed: */ @@ -74,25 +468,48 @@ static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p) resched_task(rq->curr); } -static struct task_struct *pick_next_task_rt(struct rq *rq) +static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq, + struct rt_rq *rt_rq) { - struct rt_prio_array *array = &rq->rt.active; - struct task_struct *next; + struct rt_prio_array *array = &rt_rq->active; + struct sched_rt_entity *next = NULL; struct list_head *queue; int idx; idx = sched_find_first_bit(array->bitmap); - if (idx >= MAX_RT_PRIO) - return NULL; + BUG_ON(idx >= MAX_RT_PRIO); queue = array->queue + idx; - next = list_entry(queue->next, struct task_struct, run_list); - - next->se.exec_start = rq->clock; + next = list_entry(queue->next, struct sched_rt_entity, run_list); return next; } +static struct task_struct *pick_next_task_rt(struct rq *rq) +{ + struct sched_rt_entity *rt_se; + struct task_struct *p; + struct rt_rq *rt_rq; + + rt_rq = &rq->rt; + + if (unlikely(!rt_rq->rt_nr_running)) + return NULL; + + if (sched_rt_ratio_exceeded(rt_rq)) + return NULL; + + do { + rt_se = pick_next_rt_entity(rq, rt_rq); + BUG_ON(!rt_se); + rt_rq = group_rt_rq(rt_se); + } while (rt_rq); + + p = rt_task_of(rt_se); + p->se.exec_start = rq->clock; + return p; +} + static void put_prev_task_rt(struct rq *rq, struct task_struct *p) { update_curr_rt(rq); @@ -100,76 +517,448 @@ static void put_prev_task_rt(struct rq *rq, struct task_struct *p) } #ifdef CONFIG_SMP -/* - * Load-balancing iterator. Note: while the runqueue stays locked - * during the whole iteration, the current task might be - * dequeued so the iterator has to be dequeue-safe. Here we - * achieve that by always pre-iterating before returning - * the current task: - */ -static struct task_struct *load_balance_start_rt(void *arg) + +/* Only try algorithms three times */ +#define RT_MAX_TRIES 3 + +static int double_lock_balance(struct rq *this_rq, struct rq *busiest); +static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep); + +static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu) { - struct rq *rq = arg; - struct rt_prio_array *array = &rq->rt.active; - struct list_head *head, *curr; - struct task_struct *p; + if (!task_running(rq, p) && + (cpu < 0 || cpu_isset(cpu, p->cpus_allowed)) && + (p->rt.nr_cpus_allowed > 1)) + return 1; + return 0; +} + +/* Return the second highest RT task, NULL otherwise */ +static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu) +{ + struct task_struct *next = NULL; + struct sched_rt_entity *rt_se; + struct rt_prio_array *array; + struct rt_rq *rt_rq; int idx; - idx = sched_find_first_bit(array->bitmap); - if (idx >= MAX_RT_PRIO) - return NULL; + for_each_leaf_rt_rq(rt_rq, rq) { + array = &rt_rq->active; + idx = sched_find_first_bit(array->bitmap); + next_idx: + if (idx >= MAX_RT_PRIO) + continue; + if (next && next->prio < idx) + continue; + list_for_each_entry(rt_se, array->queue + idx, run_list) { + struct task_struct *p = rt_task_of(rt_se); + if (pick_rt_task(rq, p, cpu)) { + next = p; + break; + } + } + if (!next) { + idx = find_next_bit(array->bitmap, MAX_RT_PRIO, idx+1); + goto next_idx; + } + } + + return next; +} - head = array->queue + idx; - curr = head->prev; +static DEFINE_PER_CPU(cpumask_t, local_cpu_mask); - p = list_entry(curr, struct task_struct, run_list); +static int find_lowest_cpus(struct task_struct *task, cpumask_t *lowest_mask) +{ + int lowest_prio = -1; + int lowest_cpu = -1; + int count = 0; + int cpu; - curr = curr->prev; + cpus_and(*lowest_mask, task_rq(task)->rd->online, task->cpus_allowed); - rq->rt.rt_load_balance_idx = idx; - rq->rt.rt_load_balance_head = head; - rq->rt.rt_load_balance_curr = curr; + /* + * Scan each rq for the lowest prio. + */ + for_each_cpu_mask(cpu, *lowest_mask) { + struct rq *rq = cpu_rq(cpu); - return p; + /* We look for lowest RT prio or non-rt CPU */ + if (rq->rt.highest_prio >= MAX_RT_PRIO) { + /* + * if we already found a low RT queue + * and now we found this non-rt queue + * clear the mask and set our bit. + * Otherwise just return the queue as is + * and the count==1 will cause the algorithm + * to use the first bit found. + */ + if (lowest_cpu != -1) { + cpus_clear(*lowest_mask); + cpu_set(rq->cpu, *lowest_mask); + } + return 1; + } + + /* no locking for now */ + if ((rq->rt.highest_prio > task->prio) + && (rq->rt.highest_prio >= lowest_prio)) { + if (rq->rt.highest_prio > lowest_prio) { + /* new low - clear old data */ + lowest_prio = rq->rt.highest_prio; + lowest_cpu = cpu; + count = 0; + } + count++; + } else + cpu_clear(cpu, *lowest_mask); + } + + /* + * Clear out all the set bits that represent + * runqueues that were of higher prio than + * the lowest_prio. + */ + if (lowest_cpu > 0) { + /* + * Perhaps we could add another cpumask op to + * zero out bits. Like cpu_zero_bits(cpumask, nrbits); + * Then that could be optimized to use memset and such. + */ + for_each_cpu_mask(cpu, *lowest_mask) { + if (cpu >= lowest_cpu) + break; + cpu_clear(cpu, *lowest_mask); + } + } + + return count; } -static struct task_struct *load_balance_next_rt(void *arg) +static inline int pick_optimal_cpu(int this_cpu, cpumask_t *mask) { - struct rq *rq = arg; - struct rt_prio_array *array = &rq->rt.active; - struct list_head *head, *curr; - struct task_struct *p; - int idx; + int first; + + /* "this_cpu" is cheaper to preempt than a remote processor */ + if ((this_cpu != -1) && cpu_isset(this_cpu, *mask)) + return this_cpu; + + first = first_cpu(*mask); + if (first != NR_CPUS) + return first; + + return -1; +} + +static int find_lowest_rq(struct task_struct *task) +{ + struct sched_domain *sd; + cpumask_t *lowest_mask = &__get_cpu_var(local_cpu_mask); + int this_cpu = smp_processor_id(); + int cpu = task_cpu(task); + int count = find_lowest_cpus(task, lowest_mask); + + if (!count) + return -1; /* No targets found */ - idx = rq->rt.rt_load_balance_idx; - head = rq->rt.rt_load_balance_head; - curr = rq->rt.rt_load_balance_curr; + /* + * There is no sense in performing an optimal search if only one + * target is found. + */ + if (count == 1) + return first_cpu(*lowest_mask); + + /* + * At this point we have built a mask of cpus representing the + * lowest priority tasks in the system. Now we want to elect + * the best one based on our affinity and topology. + * + * We prioritize the last cpu that the task executed on since + * it is most likely cache-hot in that location. + */ + if (cpu_isset(cpu, *lowest_mask)) + return cpu; /* - * If we arrived back to the head again then - * iterate to the next queue (if any): + * Otherwise, we consult the sched_domains span maps to figure + * out which cpu is logically closest to our hot cache data. */ - if (unlikely(head == curr)) { - int next_idx = find_next_bit(array->bitmap, MAX_RT_PRIO, idx+1); + if (this_cpu == cpu) + this_cpu = -1; /* Skip this_cpu opt if the same */ - if (next_idx >= MAX_RT_PRIO) - return NULL; + for_each_domain(cpu, sd) { + if (sd->flags & SD_WAKE_AFFINE) { + cpumask_t domain_mask; + int best_cpu; - idx = next_idx; - head = array->queue + idx; - curr = head->prev; + cpus_and(domain_mask, sd->span, *lowest_mask); - rq->rt.rt_load_balance_idx = idx; - rq->rt.rt_load_balance_head = head; + best_cpu = pick_optimal_cpu(this_cpu, + &domain_mask); + if (best_cpu != -1) + return best_cpu; + } } - p = list_entry(curr, struct task_struct, run_list); + /* + * And finally, if there were no matches within the domains + * just give the caller *something* to work with from the compatible + * locations. + */ + return pick_optimal_cpu(this_cpu, lowest_mask); +} - curr = curr->prev; +/* Will lock the rq it finds */ +static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq) +{ + struct rq *lowest_rq = NULL; + int tries; + int cpu; - rq->rt.rt_load_balance_curr = curr; + for (tries = 0; tries < RT_MAX_TRIES; tries++) { + cpu = find_lowest_rq(task); - return p; + if ((cpu == -1) || (cpu == rq->cpu)) + break; + + lowest_rq = cpu_rq(cpu); + + /* if the prio of this runqueue changed, try again */ + if (double_lock_balance(rq, lowest_rq)) { + /* + * We had to unlock the run queue. In + * the mean time, task could have + * migrated already or had its affinity changed. + * Also make sure that it wasn't scheduled on its rq. + */ + if (unlikely(task_rq(task) != rq || + !cpu_isset(lowest_rq->cpu, + task->cpus_allowed) || + task_running(rq, task) || + !task->se.on_rq)) { + + spin_unlock(&lowest_rq->lock); + lowest_rq = NULL; + break; + } + } + + /* If this rq is still suitable use it. */ + if (lowest_rq->rt.highest_prio > task->prio) + break; + + /* try again */ + spin_unlock(&lowest_rq->lock); + lowest_rq = NULL; + } + + return lowest_rq; +} + +/* + * If the current CPU has more than one RT task, see if the non + * running task can migrate over to a CPU that is running a task + * of lesser priority. + */ +static int push_rt_task(struct rq *rq) +{ + struct task_struct *next_task; + struct rq *lowest_rq; + int ret = 0; + int paranoid = RT_MAX_TRIES; + + if (!rq->rt.overloaded) + return 0; + + next_task = pick_next_highest_task_rt(rq, -1); + if (!next_task) + return 0; + + retry: + if (unlikely(next_task == rq->curr)) { + WARN_ON(1); + return 0; + } + + /* + * It's possible that the next_task slipped in of + * higher priority than current. If that's the case + * just reschedule current. + */ + if (unlikely(next_task->prio < rq->curr->prio)) { + resched_task(rq->curr); + return 0; + } + + /* We might release rq lock */ + get_task_struct(next_task); + + /* find_lock_lowest_rq locks the rq if found */ + lowest_rq = find_lock_lowest_rq(next_task, rq); + if (!lowest_rq) { + struct task_struct *task; + /* + * find lock_lowest_rq releases rq->lock + * so it is possible that next_task has changed. + * If it has, then try again. + */ + task = pick_next_highest_task_rt(rq, -1); + if (unlikely(task != next_task) && task && paranoid--) { + put_task_struct(next_task); + next_task = task; + goto retry; + } + goto out; + } + + deactivate_task(rq, next_task, 0); + set_task_cpu(next_task, lowest_rq->cpu); + activate_task(lowest_rq, next_task, 0); + + resched_task(lowest_rq->curr); + + spin_unlock(&lowest_rq->lock); + + ret = 1; +out: + put_task_struct(next_task); + + return ret; +} + +/* + * TODO: Currently we just use the second highest prio task on + * the queue, and stop when it can't migrate (or there's + * no more RT tasks). There may be a case where a lower + * priority RT task has a different affinity than the + * higher RT task. In this case the lower RT task could + * possibly be able to migrate where as the higher priority + * RT task could not. We currently ignore this issue. + * Enhancements are welcome! + */ +static void push_rt_tasks(struct rq *rq) +{ + /* push_rt_task will return true if it moved an RT */ + while (push_rt_task(rq)) + ; +} + +static int pull_rt_task(struct rq *this_rq) +{ + int this_cpu = this_rq->cpu, ret = 0, cpu; + struct task_struct *p, *next; + struct rq *src_rq; + + if (likely(!rt_overloaded(this_rq))) + return 0; + + next = pick_next_task_rt(this_rq); + + for_each_cpu_mask(cpu, this_rq->rd->rto_mask) { + if (this_cpu == cpu) + continue; + + src_rq = cpu_rq(cpu); + /* + * We can potentially drop this_rq's lock in + * double_lock_balance, and another CPU could + * steal our next task - hence we must cause + * the caller to recalculate the next task + * in that case: + */ + if (double_lock_balance(this_rq, src_rq)) { + struct task_struct *old_next = next; + + next = pick_next_task_rt(this_rq); + if (next != old_next) + ret = 1; + } + + /* + * Are there still pullable RT tasks? + */ + if (src_rq->rt.rt_nr_running <= 1) + goto skip; + + p = pick_next_highest_task_rt(src_rq, this_cpu); + + /* + * Do we have an RT task that preempts + * the to-be-scheduled task? + */ + if (p && (!next || (p->prio < next->prio))) { + WARN_ON(p == src_rq->curr); + WARN_ON(!p->se.on_rq); + + /* + * There's a chance that p is higher in priority + * than what's currently running on its cpu. + * This is just that p is wakeing up and hasn't + * had a chance to schedule. We only pull + * p if it is lower in priority than the + * current task on the run queue or + * this_rq next task is lower in prio than + * the current task on that rq. + */ + if (p->prio < src_rq->curr->prio || + (next && next->prio < src_rq->curr->prio)) + goto skip; + + ret = 1; + + deactivate_task(src_rq, p, 0); + set_task_cpu(p, this_cpu); + activate_task(this_rq, p, 0); + /* + * We continue with the search, just in + * case there's an even higher prio task + * in another runqueue. (low likelyhood + * but possible) + * + * Update next so that we won't pick a task + * on another cpu with a priority lower (or equal) + * than the one we just picked. + */ + next = p; + + } + skip: + spin_unlock(&src_rq->lock); + } + + return ret; +} + +static void pre_schedule_rt(struct rq *rq, struct task_struct *prev) +{ + /* Try to pull RT tasks here if we lower this rq's prio */ + if (unlikely(rt_task(prev)) && rq->rt.highest_prio > prev->prio) + pull_rt_task(rq); +} + +static void post_schedule_rt(struct rq *rq) +{ + /* + * If we have more than one rt_task queued, then + * see if we can push the other rt_tasks off to other CPUS. + * Note we may release the rq lock, and since + * the lock was owned by prev, we need to release it + * first via finish_lock_switch and then reaquire it here. + */ + if (unlikely(rq->rt.overloaded)) { + spin_lock_irq(&rq->lock); + push_rt_tasks(rq); + spin_unlock_irq(&rq->lock); + } +} + + +static void task_wake_up_rt(struct rq *rq, struct task_struct *p) +{ + if (!task_running(rq, p) && + (p->prio >= rq->rt.highest_prio) && + rq->rt.overloaded) + push_rt_tasks(rq); } static unsigned long @@ -178,36 +967,170 @@ load_balance_rt(struct rq *this_rq, int this_cpu, struct rq *busiest, struct sched_domain *sd, enum cpu_idle_type idle, int *all_pinned, int *this_best_prio) { - struct rq_iterator rt_rq_iterator; - - rt_rq_iterator.start = load_balance_start_rt; - rt_rq_iterator.next = load_balance_next_rt; - /* pass 'busiest' rq argument into - * load_balance_[start|next]_rt iterators - */ - rt_rq_iterator.arg = busiest; - - return balance_tasks(this_rq, this_cpu, busiest, max_load_move, sd, - idle, all_pinned, this_best_prio, &rt_rq_iterator); + /* don't touch RT tasks */ + return 0; } static int move_one_task_rt(struct rq *this_rq, int this_cpu, struct rq *busiest, struct sched_domain *sd, enum cpu_idle_type idle) { - struct rq_iterator rt_rq_iterator; + /* don't touch RT tasks */ + return 0; +} + +static void set_cpus_allowed_rt(struct task_struct *p, cpumask_t *new_mask) +{ + int weight = cpus_weight(*new_mask); - rt_rq_iterator.start = load_balance_start_rt; - rt_rq_iterator.next = load_balance_next_rt; - rt_rq_iterator.arg = busiest; + BUG_ON(!rt_task(p)); + + /* + * Update the migration status of the RQ if we have an RT task + * which is running AND changing its weight value. + */ + if (p->se.on_rq && (weight != p->rt.nr_cpus_allowed)) { + struct rq *rq = task_rq(p); - return iter_move_one_task(this_rq, this_cpu, busiest, sd, idle, - &rt_rq_iterator); + if ((p->rt.nr_cpus_allowed <= 1) && (weight > 1)) { + rq->rt.rt_nr_migratory++; + } else if ((p->rt.nr_cpus_allowed > 1) && (weight <= 1)) { + BUG_ON(!rq->rt.rt_nr_migratory); + rq->rt.rt_nr_migratory--; + } + + update_rt_migration(rq); + } + + p->cpus_allowed = *new_mask; + p->rt.nr_cpus_allowed = weight; } -#endif -static void task_tick_rt(struct rq *rq, struct task_struct *p) +/* Assumes rq->lock is held */ +static void join_domain_rt(struct rq *rq) { + if (rq->rt.overloaded) + rt_set_overload(rq); +} + +/* Assumes rq->lock is held */ +static void leave_domain_rt(struct rq *rq) +{ + if (rq->rt.overloaded) + rt_clear_overload(rq); +} + +/* + * When switch from the rt queue, we bring ourselves to a position + * that we might want to pull RT tasks from other runqueues. + */ +static void switched_from_rt(struct rq *rq, struct task_struct *p, + int running) +{ + /* + * If there are other RT tasks then we will reschedule + * and the scheduling of the other RT tasks will handle + * the balancing. But if we are the last RT task + * we may need to handle the pulling of RT tasks + * now. + */ + if (!rq->rt.rt_nr_running) + pull_rt_task(rq); +} +#endif /* CONFIG_SMP */ + +/* + * When switching a task to RT, we may overload the runqueue + * with RT tasks. In this case we try to push them off to + * other runqueues. + */ +static void switched_to_rt(struct rq *rq, struct task_struct *p, + int running) +{ + int check_resched = 1; + + /* + * If we are already running, then there's nothing + * that needs to be done. But if we are not running + * we may need to preempt the current running task. + * If that current running task is also an RT task + * then see if we can move to another run queue. + */ + if (!running) { +#ifdef CONFIG_SMP + if (rq->rt.overloaded && push_rt_task(rq) && + /* Don't resched if we changed runqueues */ + rq != task_rq(p)) + check_resched = 0; +#endif /* CONFIG_SMP */ + if (check_resched && p->prio < rq->curr->prio) + resched_task(rq->curr); + } +} + +/* + * Priority of the task has changed. This may cause + * us to initiate a push or pull. + */ +static void prio_changed_rt(struct rq *rq, struct task_struct *p, + int oldprio, int running) +{ + if (running) { +#ifdef CONFIG_SMP + /* + * If our priority decreases while running, we + * may need to pull tasks to this runqueue. + */ + if (oldprio < p->prio) + pull_rt_task(rq); + /* + * If there's a higher priority task waiting to run + * then reschedule. + */ + if (p->prio > rq->rt.highest_prio) + resched_task(p); +#else + /* For UP simply resched on drop of prio */ + if (oldprio < p->prio) + resched_task(p); +#endif /* CONFIG_SMP */ + } else { + /* + * This task is not running, but if it is + * greater than the current running task + * then reschedule. + */ + if (p->prio < rq->curr->prio) + resched_task(rq->curr); + } +} + +static void watchdog(struct rq *rq, struct task_struct *p) +{ + unsigned long soft, hard; + + if (!p->signal) + return; + + soft = p->signal->rlim[RLIMIT_RTTIME].rlim_cur; + hard = p->signal->rlim[RLIMIT_RTTIME].rlim_max; + + if (soft != RLIM_INFINITY) { + unsigned long next; + + p->rt.timeout++; + next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ); + if (p->rt.timeout > next) + p->it_sched_expires = p->se.sum_exec_runtime; + } +} + +static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued) +{ + update_curr_rt(rq); + + watchdog(rq, p); + /* * RR tasks need a special form of timeslice management. * FIFO tasks have no timeslices. @@ -215,16 +1138,16 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p) if (p->policy != SCHED_RR) return; - if (--p->time_slice) + if (--p->rt.time_slice) return; - p->time_slice = DEF_TIMESLICE; + p->rt.time_slice = DEF_TIMESLICE; /* * Requeue to the end of queue if we are not the only element * on the queue: */ - if (p->run_list.prev != p->run_list.next) { + if (p->rt.run_list.prev != p->rt.run_list.next) { requeue_task_rt(rq, p); set_tsk_need_resched(p); } @@ -242,6 +1165,9 @@ const struct sched_class rt_sched_class = { .enqueue_task = enqueue_task_rt, .dequeue_task = dequeue_task_rt, .yield_task = yield_task_rt, +#ifdef CONFIG_SMP + .select_task_rq = select_task_rq_rt, +#endif /* CONFIG_SMP */ .check_preempt_curr = check_preempt_curr_rt, @@ -251,8 +1177,18 @@ const struct sched_class rt_sched_class = { #ifdef CONFIG_SMP .load_balance = load_balance_rt, .move_one_task = move_one_task_rt, + .set_cpus_allowed = set_cpus_allowed_rt, + .join_domain = join_domain_rt, + .leave_domain = leave_domain_rt, + .pre_schedule = pre_schedule_rt, + .post_schedule = post_schedule_rt, + .task_wake_up = task_wake_up_rt, + .switched_from = switched_from_rt, #endif .set_curr_task = set_curr_task_rt, .task_tick = task_tick_rt, + + .prio_changed = prio_changed_rt, + .switched_to = switched_to_rt, }; diff --git a/kernel/signal.c b/kernel/signal.c index afa4f781f92..5d30ff56184 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -456,15 +456,15 @@ void signal_wake_up(struct task_struct *t, int resume) set_tsk_thread_flag(t, TIF_SIGPENDING); /* - * For SIGKILL, we want to wake it up in the stopped/traced case. - * We don't check t->state here because there is a race with it + * For SIGKILL, we want to wake it up in the stopped/traced/killable + * case. We don't check t->state here because there is a race with it * executing another processor and just now entering stopped state. * By using wake_up_state, we ensure the process will wake up and * handle its death signal. */ mask = TASK_INTERRUPTIBLE; if (resume) - mask |= TASK_STOPPED | TASK_TRACED; + mask |= TASK_WAKEKILL; if (!wake_up_state(t, mask)) kick_process(t); } @@ -620,7 +620,7 @@ static void handle_stop_signal(int sig, struct task_struct *p) * Wake up the stopped thread _after_ setting * TIF_SIGPENDING */ - state = TASK_STOPPED; + state = __TASK_STOPPED; if (sig_user_defined(t, SIGCONT) && !sigismember(&t->blocked, SIGCONT)) { set_tsk_thread_flag(t, TIF_SIGPENDING); state |= TASK_INTERRUPTIBLE; @@ -733,13 +733,13 @@ static void print_fatal_signal(struct pt_regs *regs, int signr) current->comm, task_pid_nr(current), signr); #if defined(__i386__) && !defined(__arch_um__) - printk("code at %08lx: ", regs->eip); + printk("code at %08lx: ", regs->ip); { int i; for (i = 0; i < 16; i++) { unsigned char insn; - __get_user(insn, (unsigned char *)(regs->eip + i)); + __get_user(insn, (unsigned char *)(regs->ip + i)); printk("%02x ", insn); } } @@ -838,7 +838,7 @@ static inline int wants_signal(int sig, struct task_struct *p) return 0; if (sig == SIGKILL) return 1; - if (p->state & (TASK_STOPPED | TASK_TRACED)) + if (task_is_stopped_or_traced(p)) return 0; return task_curr(p) || !signal_pending(p); } @@ -911,27 +911,6 @@ __group_complete_signal(int sig, struct task_struct *p) } while_each_thread(p, t); return; } - - /* - * There will be a core dump. We make all threads other - * than the chosen one go into a group stop so that nothing - * happens until it gets scheduled, takes the signal off - * the shared queue, and does the core dump. This is a - * little more complicated than strictly necessary, but it - * keeps the signal state that winds up in the core dump - * unchanged from the death state, e.g. which thread had - * the core-dump signal unblocked. - */ - rm_from_queue(SIG_KERNEL_STOP_MASK, &t->pending); - rm_from_queue(SIG_KERNEL_STOP_MASK, &p->signal->shared_pending); - p->signal->group_stop_count = 0; - p->signal->group_exit_task = t; - p = t; - do { - p->signal->group_stop_count++; - signal_wake_up(t, t == p); - } while_each_thread(p, t); - return; } /* @@ -978,7 +957,6 @@ void zap_other_threads(struct task_struct *p) { struct task_struct *t; - p->signal->flags = SIGNAL_GROUP_EXIT; p->signal->group_stop_count = 0; for (t = next_thread(p); t != p; t = next_thread(t)) { @@ -994,6 +972,12 @@ void zap_other_threads(struct task_struct *p) } } +int fastcall __fatal_signal_pending(struct task_struct *tsk) +{ + return sigismember(&tsk->pending.signal, SIGKILL); +} +EXPORT_SYMBOL(__fatal_signal_pending); + /* * Must be called under rcu_read_lock() or with tasklist_lock read-held. */ @@ -1441,7 +1425,7 @@ void do_notify_parent(struct task_struct *tsk, int sig) BUG_ON(sig == -1); /* do_notify_parent_cldstop should have been called instead. */ - BUG_ON(tsk->state & (TASK_STOPPED|TASK_TRACED)); + BUG_ON(task_is_stopped_or_traced(tsk)); BUG_ON(!tsk->ptrace && (tsk->group_leader != tsk || !thread_group_empty(tsk))); @@ -1594,6 +1578,17 @@ static inline int may_ptrace_stop(void) } /* + * Return nonzero if there is a SIGKILL that should be waking us up. + * Called with the siglock held. + */ +static int sigkill_pending(struct task_struct *tsk) +{ + return ((sigismember(&tsk->pending.signal, SIGKILL) || + sigismember(&tsk->signal->shared_pending.signal, SIGKILL)) && + !unlikely(sigismember(&tsk->blocked, SIGKILL))); +} + +/* * This must be called with current->sighand->siglock held. * * This should be the path for all ptrace stops. @@ -1606,6 +1601,26 @@ static inline int may_ptrace_stop(void) */ static void ptrace_stop(int exit_code, int nostop_code, siginfo_t *info) { + int killed = 0; + + if (arch_ptrace_stop_needed(exit_code, info)) { + /* + * The arch code has something special to do before a + * ptrace stop. This is allowed to block, e.g. for faults + * on user stack pages. We can't keep the siglock while + * calling arch_ptrace_stop, so we must release it now. + * To preserve proper semantics, we must do this before + * any signal bookkeeping like checking group_stop_count. + * Meanwhile, a SIGKILL could come in before we retake the + * siglock. That must prevent us from sleeping in TASK_TRACED. + * So after regaining the lock, we must check for SIGKILL. + */ + spin_unlock_irq(¤t->sighand->siglock); + arch_ptrace_stop(exit_code, info); + spin_lock_irq(¤t->sighand->siglock); + killed = sigkill_pending(current); + } + /* * If there is a group stop in progress, * we must participate in the bookkeeping. @@ -1617,11 +1632,11 @@ static void ptrace_stop(int exit_code, int nostop_code, siginfo_t *info) current->exit_code = exit_code; /* Let the debugger run. */ - set_current_state(TASK_TRACED); + __set_current_state(TASK_TRACED); spin_unlock_irq(¤t->sighand->siglock); try_to_freeze(); read_lock(&tasklist_lock); - if (may_ptrace_stop()) { + if (!unlikely(killed) && may_ptrace_stop()) { do_notify_parent_cldstop(current, CLD_TRAPPED); read_unlock(&tasklist_lock); schedule(); @@ -1703,9 +1718,6 @@ static int do_signal_stop(int signr) struct signal_struct *sig = current->signal; int stop_count; - if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED)) - return 0; - if (sig->group_stop_count > 0) { /* * There is a group stop in progress. We don't need to @@ -1713,12 +1725,15 @@ static int do_signal_stop(int signr) */ stop_count = --sig->group_stop_count; } else { + struct task_struct *t; + + if (!likely(sig->flags & SIGNAL_STOP_DEQUEUED) || + unlikely(sig->group_exit_task)) + return 0; /* * There is no group stop already in progress. * We must initiate one now. */ - struct task_struct *t; - sig->group_exit_code = signr; stop_count = 0; @@ -1729,7 +1744,7 @@ static int do_signal_stop(int signr) * so this check has no races. */ if (!t->exit_state && - !(t->state & (TASK_STOPPED|TASK_TRACED))) { + !task_is_stopped_or_traced(t)) { stop_count++; signal_wake_up(t, 0); } @@ -1746,47 +1761,6 @@ static int do_signal_stop(int signr) return 1; } -/* - * Do appropriate magic when group_stop_count > 0. - * We return nonzero if we stopped, after releasing the siglock. - * We return zero if we still hold the siglock and should look - * for another signal without checking group_stop_count again. - */ -static int handle_group_stop(void) -{ - int stop_count; - - if (current->signal->group_exit_task == current) { - /* - * Group stop is so we can do a core dump, - * We are the initiating thread, so get on with it. - */ - current->signal->group_exit_task = NULL; - return 0; - } - - if (current->signal->flags & SIGNAL_GROUP_EXIT) - /* - * Group stop is so another thread can do a core dump, - * or else we are racing against a death signal. - * Just punt the stop so we can get the next signal. - */ - return 0; - - /* - * There is a group stop in progress. We stop - * without any associated signal being in our queue. - */ - stop_count = --current->signal->group_stop_count; - if (stop_count == 0) - current->signal->flags = SIGNAL_STOP_STOPPED; - current->exit_code = current->signal->group_exit_code; - set_current_state(TASK_STOPPED); - spin_unlock_irq(¤t->sighand->siglock); - finish_stop(stop_count); - return 1; -} - int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie) { @@ -1801,7 +1775,7 @@ relock: struct k_sigaction *ka; if (unlikely(current->signal->group_stop_count > 0) && - handle_group_stop()) + do_signal_stop(0)) goto relock; signr = dequeue_signal(current, mask, info); diff --git a/kernel/softirq.c b/kernel/softirq.c index bd89bc4eb0b..d7837d45419 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -3,7 +3,9 @@ * * Copyright (C) 1992 Linus Torvalds * - * Rewritten. Old one was good in 2.2, but in 2.3 it was immoral. --ANK (990903) + * Distribute under GPLv2. + * + * Rewritten. Old one was good in 2.2, but in 2.3 it was immoral. --ANK (990903) */ #include <linux/module.h> @@ -278,9 +280,14 @@ asmlinkage void do_softirq(void) */ void irq_enter(void) { +#ifdef CONFIG_NO_HZ + int cpu = smp_processor_id(); + if (idle_cpu(cpu) && !in_interrupt()) + tick_nohz_stop_idle(cpu); +#endif __irq_enter(); #ifdef CONFIG_NO_HZ - if (idle_cpu(smp_processor_id())) + if (idle_cpu(cpu)) tick_nohz_update_jiffies(); #endif } diff --git a/kernel/softlockup.c b/kernel/softlockup.c index 11df812263c..7c2da88db4e 100644 --- a/kernel/softlockup.c +++ b/kernel/softlockup.c @@ -8,6 +8,7 @@ */ #include <linux/mm.h> #include <linux/cpu.h> +#include <linux/nmi.h> #include <linux/init.h> #include <linux/delay.h> #include <linux/freezer.h> @@ -23,8 +24,8 @@ static DEFINE_PER_CPU(unsigned long, touch_timestamp); static DEFINE_PER_CPU(unsigned long, print_timestamp); static DEFINE_PER_CPU(struct task_struct *, watchdog_task); -static int did_panic; -int softlockup_thresh = 10; +static int __read_mostly did_panic; +unsigned long __read_mostly softlockup_thresh = 60; static int softlock_panic(struct notifier_block *this, unsigned long event, void *ptr) @@ -45,7 +46,7 @@ static struct notifier_block panic_block = { */ static unsigned long get_timestamp(int this_cpu) { - return cpu_clock(this_cpu) >> 30; /* 2^30 ~= 10^9 */ + return cpu_clock(this_cpu) >> 30LL; /* 2^30 ~= 10^9 */ } void touch_softlockup_watchdog(void) @@ -104,7 +105,7 @@ void softlockup_tick(void) if (now > (touch_timestamp + 1)) wake_up_process(per_cpu(watchdog_task, this_cpu)); - /* Warn about unreasonable 10+ seconds delays: */ + /* Warn about unreasonable delays: */ if (now <= (touch_timestamp + softlockup_thresh)) return; @@ -122,11 +123,93 @@ void softlockup_tick(void) } /* + * Have a reasonable limit on the number of tasks checked: + */ +unsigned long __read_mostly sysctl_hung_task_check_count = 1024; + +/* + * Zero means infinite timeout - no checking done: + */ +unsigned long __read_mostly sysctl_hung_task_timeout_secs = 120; + +unsigned long __read_mostly sysctl_hung_task_warnings = 10; + +/* + * Only do the hung-tasks check on one CPU: + */ +static int check_cpu __read_mostly = -1; + +static void check_hung_task(struct task_struct *t, unsigned long now) +{ + unsigned long switch_count = t->nvcsw + t->nivcsw; + + if (t->flags & PF_FROZEN) + return; + + if (switch_count != t->last_switch_count || !t->last_switch_timestamp) { + t->last_switch_count = switch_count; + t->last_switch_timestamp = now; + return; + } + if ((long)(now - t->last_switch_timestamp) < + sysctl_hung_task_timeout_secs) + return; + if (sysctl_hung_task_warnings < 0) + return; + sysctl_hung_task_warnings--; + + /* + * Ok, the task did not get scheduled for more than 2 minutes, + * complain: + */ + printk(KERN_ERR "INFO: task %s:%d blocked for more than " + "%ld seconds.\n", t->comm, t->pid, + sysctl_hung_task_timeout_secs); + printk(KERN_ERR "\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\"" + " disables this message.\n"); + sched_show_task(t); + __debug_show_held_locks(t); + + t->last_switch_timestamp = now; + touch_nmi_watchdog(); +} + +/* + * Check whether a TASK_UNINTERRUPTIBLE does not get woken up for + * a really long time (120 seconds). If that happens, print out + * a warning. + */ +static void check_hung_uninterruptible_tasks(int this_cpu) +{ + int max_count = sysctl_hung_task_check_count; + unsigned long now = get_timestamp(this_cpu); + struct task_struct *g, *t; + + /* + * If the system crashed already then all bets are off, + * do not report extra hung tasks: + */ + if ((tainted & TAINT_DIE) || did_panic) + return; + + read_lock(&tasklist_lock); + do_each_thread(g, t) { + if (!--max_count) + goto unlock; + if (t->state & TASK_UNINTERRUPTIBLE) + check_hung_task(t, now); + } while_each_thread(g, t); + unlock: + read_unlock(&tasklist_lock); +} + +/* * The watchdog thread - runs every second and touches the timestamp. */ static int watchdog(void *__bind_cpu) { struct sched_param param = { .sched_priority = MAX_RT_PRIO-1 }; + int this_cpu = (long)__bind_cpu; sched_setscheduler(current, SCHED_FIFO, ¶m); @@ -135,13 +218,23 @@ static int watchdog(void *__bind_cpu) /* * Run briefly once per second to reset the softlockup timestamp. - * If this gets delayed for more than 10 seconds then the + * If this gets delayed for more than 60 seconds then the * debug-printout triggers in softlockup_tick(). */ while (!kthread_should_stop()) { set_current_state(TASK_INTERRUPTIBLE); touch_softlockup_watchdog(); schedule(); + + if (kthread_should_stop()) + break; + + if (this_cpu != check_cpu) + continue; + + if (sysctl_hung_task_timeout_secs) + check_hung_uninterruptible_tasks(this_cpu); + } return 0; @@ -171,9 +264,20 @@ cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu) break; case CPU_ONLINE: case CPU_ONLINE_FROZEN: + check_cpu = any_online_cpu(cpu_online_map); wake_up_process(per_cpu(watchdog_task, hotcpu)); break; #ifdef CONFIG_HOTPLUG_CPU + case CPU_DOWN_PREPARE: + case CPU_DOWN_PREPARE_FROZEN: + if (hotcpu == check_cpu) { + cpumask_t temp_cpu_online_map = cpu_online_map; + + cpu_clear(hotcpu, temp_cpu_online_map); + check_cpu = any_online_cpu(temp_cpu_online_map); + } + break; + case CPU_UP_CANCELED: case CPU_UP_CANCELED_FROZEN: if (!per_cpu(watchdog_task, hotcpu)) diff --git a/kernel/spinlock.c b/kernel/spinlock.c index cd72424c266..ae28c824512 100644 --- a/kernel/spinlock.c +++ b/kernel/spinlock.c @@ -65,8 +65,7 @@ EXPORT_SYMBOL(_write_trylock); * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are * not re-enabled during lock-acquire (which the preempt-spin-ops do): */ -#if !defined(CONFIG_PREEMPT) || !defined(CONFIG_SMP) || \ - defined(CONFIG_DEBUG_LOCK_ALLOC) +#if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC) void __lockfunc _read_lock(rwlock_t *lock) { diff --git a/kernel/srcu.c b/kernel/srcu.c index 3507cabe963..b0aeeaf22ce 100644 --- a/kernel/srcu.c +++ b/kernel/srcu.c @@ -74,7 +74,7 @@ static int srcu_readers_active_idx(struct srcu_struct *sp, int idx) * severe errors when invoked on an active srcu_struct. That said, it * can be useful as an error check at cleanup time. */ -int srcu_readers_active(struct srcu_struct *sp) +static int srcu_readers_active(struct srcu_struct *sp) { return srcu_readers_active_idx(sp, 0) + srcu_readers_active_idx(sp, 1); } @@ -255,4 +255,3 @@ EXPORT_SYMBOL_GPL(srcu_read_lock); EXPORT_SYMBOL_GPL(srcu_read_unlock); EXPORT_SYMBOL_GPL(synchronize_srcu); EXPORT_SYMBOL_GPL(srcu_batches_completed); -EXPORT_SYMBOL_GPL(srcu_readers_active); diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 319821ef78a..6f4e0e13f70 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -29,7 +29,6 @@ enum stopmachine_state { static enum stopmachine_state stopmachine_state; static unsigned int stopmachine_num_threads; static atomic_t stopmachine_thread_ack; -static DECLARE_MUTEX(stopmachine_mutex); static int stopmachine(void *cpu) { @@ -170,6 +169,7 @@ static int do_stop(void *_smdata) struct task_struct *__stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) { + static DEFINE_MUTEX(stopmachine_mutex); struct stop_machine_data smdata; struct task_struct *p; @@ -177,7 +177,7 @@ struct task_struct *__stop_machine_run(int (*fn)(void *), void *data, smdata.data = data; init_completion(&smdata.done); - down(&stopmachine_mutex); + mutex_lock(&stopmachine_mutex); /* If they don't care which CPU fn runs on, bind to any online one. */ if (cpu == NR_CPUS) @@ -193,7 +193,7 @@ struct task_struct *__stop_machine_run(int (*fn)(void *), void *data, wake_up_process(p); wait_for_completion(&smdata.done); } - up(&stopmachine_mutex); + mutex_unlock(&stopmachine_mutex); return p; } @@ -203,13 +203,13 @@ int stop_machine_run(int (*fn)(void *), void *data, unsigned int cpu) int ret; /* No CPUs can come up or down during this. */ - lock_cpu_hotplug(); + get_online_cpus(); p = __stop_machine_run(fn, data, cpu); if (!IS_ERR(p)) ret = kthread_stop(p); else ret = PTR_ERR(p); - unlock_cpu_hotplug(); + put_online_cpus(); return ret; } diff --git a/kernel/sys.c b/kernel/sys.c index d1fe71eb454..e3c08d4324d 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -315,7 +315,7 @@ static void kernel_kexec(void) #endif } -void kernel_shutdown_prepare(enum system_states state) +static void kernel_shutdown_prepare(enum system_states state) { blocking_notifier_call_chain(&reboot_notifier_list, (state == SYSTEM_HALT)?SYS_HALT:SYS_POWER_OFF, NULL); @@ -1145,16 +1145,16 @@ static int groups_to_user(gid_t __user *grouplist, struct group_info *group_info) { int i; - int count = group_info->ngroups; + unsigned int count = group_info->ngroups; for (i = 0; i < group_info->nblocks; i++) { - int cp_count = min(NGROUPS_PER_BLOCK, count); - int off = i * NGROUPS_PER_BLOCK; - int len = cp_count * sizeof(*grouplist); + unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); + unsigned int len = cp_count * sizeof(*grouplist); - if (copy_to_user(grouplist+off, group_info->blocks[i], len)) + if (copy_to_user(grouplist, group_info->blocks[i], len)) return -EFAULT; + grouplist += NGROUPS_PER_BLOCK; count -= cp_count; } return 0; @@ -1165,16 +1165,16 @@ static int groups_from_user(struct group_info *group_info, gid_t __user *grouplist) { int i; - int count = group_info->ngroups; + unsigned int count = group_info->ngroups; for (i = 0; i < group_info->nblocks; i++) { - int cp_count = min(NGROUPS_PER_BLOCK, count); - int off = i * NGROUPS_PER_BLOCK; - int len = cp_count * sizeof(*grouplist); + unsigned int cp_count = min(NGROUPS_PER_BLOCK, count); + unsigned int len = cp_count * sizeof(*grouplist); - if (copy_from_user(group_info->blocks[i], grouplist+off, len)) + if (copy_from_user(group_info->blocks[i], grouplist, len)) return -EFAULT; + grouplist += NGROUPS_PER_BLOCK; count -= cp_count; } return 0; @@ -1472,7 +1472,7 @@ asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim) if ((new_rlim.rlim_max > old_rlim->rlim_max) && !capable(CAP_SYS_RESOURCE)) return -EPERM; - if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > NR_OPEN) + if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) return -EPERM; retval = security_task_setrlimit(resource, &new_rlim); @@ -1637,7 +1637,7 @@ asmlinkage long sys_umask(int mask) mask = xchg(¤t->fs->umask, mask & S_IRWXUGO); return mask; } - + asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4, unsigned long arg5) { @@ -1742,6 +1742,17 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3, error = prctl_set_seccomp(arg2); break; + case PR_CAPBSET_READ: + if (!cap_valid(arg2)) + return -EINVAL; + return !!cap_raised(current->cap_bset, arg2); + case PR_CAPBSET_DROP: +#ifdef CONFIG_SECURITY_FILE_CAPABILITIES + return cap_prctl_drop(arg2); +#else + return -EINVAL; +#endif + default: error = -EINVAL; break; diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 56cb009a4b3..5b9b467de07 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -131,6 +131,7 @@ cond_syscall(sys32_sysctl); cond_syscall(ppc_rtas); cond_syscall(sys_spu_run); cond_syscall(sys_spu_create); +cond_syscall(sys_subpage_prot); /* mmu depending weak syscall entries */ cond_syscall(sys_mprotect); @@ -153,7 +154,10 @@ cond_syscall(sys_ioprio_get); /* New file descriptors */ cond_syscall(sys_signalfd); -cond_syscall(sys_timerfd); cond_syscall(compat_sys_signalfd); -cond_syscall(compat_sys_timerfd); +cond_syscall(sys_timerfd_create); +cond_syscall(sys_timerfd_settime); +cond_syscall(sys_timerfd_gettime); +cond_syscall(compat_sys_timerfd_settime); +cond_syscall(compat_sys_timerfd_gettime); cond_syscall(sys_eventfd); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 8ac51714b08..86daaa26d12 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -53,6 +53,7 @@ #ifdef CONFIG_X86 #include <asm/nmi.h> #include <asm/stacktrace.h> +#include <asm/io.h> #endif static int deprecated_sysctl_warning(struct __sysctl_args *args); @@ -80,11 +81,14 @@ extern int percpu_pagelist_fraction; extern int compat_log; extern int maps_protect; extern int sysctl_stat_interval; -extern int audit_argv_kb; +extern int latencytop_enabled; /* Constants used for minimum and maximum */ -#ifdef CONFIG_DETECT_SOFTLOCKUP +#if defined(CONFIG_DETECT_SOFTLOCKUP) || defined(CONFIG_HIGHMEM) static int one = 1; +#endif + +#ifdef CONFIG_DETECT_SOFTLOCKUP static int sixty = 60; #endif @@ -156,8 +160,16 @@ static int proc_dointvec_taint(struct ctl_table *table, int write, struct file * #endif static struct ctl_table root_table[]; -static struct ctl_table_header root_table_header = - { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) }; +static struct ctl_table_root sysctl_table_root; +static struct ctl_table_header root_table_header = { + .ctl_table = root_table, + .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.header_list), + .root = &sysctl_table_root, +}; +static struct ctl_table_root sysctl_table_root = { + .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list), + .header_list = LIST_HEAD_INIT(root_table_header.ctl_entry), +}; static struct ctl_table kern_table[]; static struct ctl_table vm_table[]; @@ -191,14 +203,6 @@ static struct ctl_table root_table[] = { .mode = 0555, .child = vm_table, }, -#ifdef CONFIG_NET - { - .ctl_name = CTL_NET, - .procname = "net", - .mode = 0555, - .child = net_table, - }, -#endif { .ctl_name = CTL_FS, .procname = "fs", @@ -225,10 +229,10 @@ static struct ctl_table root_table[] = { }; #ifdef CONFIG_SCHED_DEBUG -static unsigned long min_sched_granularity_ns = 100000; /* 100 usecs */ -static unsigned long max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ -static unsigned long min_wakeup_granularity_ns; /* 0 usecs */ -static unsigned long max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ +static int min_sched_granularity_ns = 100000; /* 100 usecs */ +static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ +static int min_wakeup_granularity_ns; /* 0 usecs */ +static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ #endif static struct ctl_table kern_table[] = { @@ -306,9 +310,43 @@ static struct ctl_table kern_table[] = { .procname = "sched_nr_migrate", .data = &sysctl_sched_nr_migrate, .maxlen = sizeof(unsigned int), - .mode = 644, + .mode = 0644, .proc_handler = &proc_dointvec, }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_rt_period_ms", + .data = &sysctl_sched_rt_period, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_rt_ratio", + .data = &sysctl_sched_rt_ratio, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, +#if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP) + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_min_bal_int_shares", + .data = &sysctl_sched_min_bal_int_shares, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "sched_max_bal_int_shares", + .data = &sysctl_sched_max_bal_int_shares, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, +#endif #endif { .ctl_name = CTL_UNNUMBERED, @@ -354,16 +392,6 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = &proc_dointvec, }, -#ifdef CONFIG_AUDITSYSCALL - { - .ctl_name = CTL_UNNUMBERED, - .procname = "audit_argv_kb", - .data = &audit_argv_kb, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = &proc_dointvec, - }, -#endif { .ctl_name = KERN_CORE_PATTERN, .procname = "core_pattern", @@ -382,15 +410,15 @@ static struct ctl_table kern_table[] = { .proc_handler = &proc_dointvec_taint, }, #endif -#ifdef CONFIG_SECURITY_CAPABILITIES +#ifdef CONFIG_LATENCYTOP { - .procname = "cap-bound", - .data = &cap_bset, - .maxlen = sizeof(kernel_cap_t), - .mode = 0600, - .proc_handler = &proc_dointvec_bset, + .procname = "latencytop", + .data = &latencytop_enabled, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, }, -#endif /* def CONFIG_SECURITY_CAPABILITIES */ +#endif #ifdef CONFIG_BLK_DEV_INITRD { .ctl_name = KERN_REALROOTDEV, @@ -683,6 +711,14 @@ static struct ctl_table kern_table[] = { .mode = 0644, .proc_handler = &proc_dointvec, }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "io_delay_type", + .data = &io_delay_type, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, #endif #if defined(CONFIG_MMU) { @@ -728,13 +764,40 @@ static struct ctl_table kern_table[] = { .ctl_name = CTL_UNNUMBERED, .procname = "softlockup_thresh", .data = &softlockup_thresh, - .maxlen = sizeof(int), + .maxlen = sizeof(unsigned long), .mode = 0644, - .proc_handler = &proc_dointvec_minmax, + .proc_handler = &proc_doulongvec_minmax, .strategy = &sysctl_intvec, .extra1 = &one, .extra2 = &sixty, }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "hung_task_check_count", + .data = &sysctl_hung_task_check_count, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .strategy = &sysctl_intvec, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "hung_task_timeout_secs", + .data = &sysctl_hung_task_timeout_secs, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .strategy = &sysctl_intvec, + }, + { + .ctl_name = CTL_UNNUMBERED, + .procname = "hung_task_warnings", + .data = &sysctl_hung_task_warnings, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .strategy = &sysctl_intvec, + }, #endif #ifdef CONFIG_COMPAT { @@ -906,11 +969,11 @@ static struct ctl_table vm_table[] = { }, { .ctl_name = CTL_UNNUMBERED, - .procname = "hugetlb_dynamic_pool", - .data = &hugetlb_dynamic_pool, - .maxlen = sizeof(hugetlb_dynamic_pool), + .procname = "nr_overcommit_hugepages", + .data = &nr_overcommit_huge_pages, + .maxlen = sizeof(nr_overcommit_huge_pages), .mode = 0644, - .proc_handler = &proc_dointvec, + .proc_handler = &proc_doulongvec_minmax, }, #endif { @@ -1081,6 +1144,19 @@ static struct ctl_table vm_table[] = { .extra1 = &zero, }, #endif +#ifdef CONFIG_HIGHMEM + { + .ctl_name = CTL_UNNUMBERED, + .procname = "highmem_is_dirtyable", + .data = &vm_highmem_is_dirtyable, + .maxlen = sizeof(vm_highmem_is_dirtyable), + .mode = 0644, + .proc_handler = &proc_dointvec_minmax, + .strategy = &sysctl_intvec, + .extra1 = &zero, + .extra2 = &one, + }, +#endif /* * NOTE: do not add new entries to this table unless you have read * Documentation/sysctl/ctl_unnumbered.txt @@ -1127,6 +1203,14 @@ static struct ctl_table fs_table[] = { .proc_handler = &proc_dointvec, }, { + .ctl_name = CTL_UNNUMBERED, + .procname = "nr_open", + .data = &sysctl_nr_open, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { .ctl_name = FS_DENTRY, .procname = "dentry-state", .data = &dentry_stat, @@ -1300,12 +1384,27 @@ void sysctl_head_finish(struct ctl_table_header *head) spin_unlock(&sysctl_lock); } -struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) +static struct list_head * +lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces) +{ + struct list_head *header_list; + header_list = &root->header_list; + if (root->lookup) + header_list = root->lookup(root, namespaces); + return header_list; +} + +struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces, + struct ctl_table_header *prev) { + struct ctl_table_root *root; + struct list_head *header_list; struct ctl_table_header *head; struct list_head *tmp; + spin_lock(&sysctl_lock); if (prev) { + head = prev; tmp = &prev->ctl_entry; unuse_table(prev); goto next; @@ -1319,14 +1418,38 @@ struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) spin_unlock(&sysctl_lock); return head; next: + root = head->root; tmp = tmp->next; - if (tmp == &root_table_header.ctl_entry) - break; + header_list = lookup_header_list(root, namespaces); + if (tmp != header_list) + continue; + + do { + root = list_entry(root->root_list.next, + struct ctl_table_root, root_list); + if (root == &sysctl_table_root) + goto out; + header_list = lookup_header_list(root, namespaces); + } while (list_empty(header_list)); + tmp = header_list->next; } +out: spin_unlock(&sysctl_lock); return NULL; } +struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) +{ + return __sysctl_head_next(current->nsproxy, prev); +} + +void register_sysctl_root(struct ctl_table_root *root) +{ + spin_lock(&sysctl_lock); + list_add_tail(&root->root_list, &sysctl_table_root.root_list); + spin_unlock(&sysctl_lock); +} + #ifdef CONFIG_SYSCTL_SYSCALL int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, void __user *newval, size_t newlen) @@ -1483,18 +1606,21 @@ static __init int sysctl_init(void) { int err; sysctl_set_parent(NULL, root_table); - err = sysctl_check_table(root_table); + err = sysctl_check_table(current->nsproxy, root_table); return 0; } core_initcall(sysctl_init); /** - * register_sysctl_table - register a sysctl hierarchy + * __register_sysctl_paths - register a sysctl hierarchy + * @root: List of sysctl headers to register on + * @namespaces: Data to compute which lists of sysctl entries are visible + * @path: The path to the directory the sysctl table is in. * @table: the top-level table structure * * Register a sysctl table hierarchy. @table should be a filled in ctl_table - * array. An entry with a ctl_name of 0 terminates the table. + * array. A completely 0 filled entry terminates the table. * * The members of the &struct ctl_table structure are used as follows: * @@ -1557,25 +1683,99 @@ core_initcall(sysctl_init); * This routine returns %NULL on a failure to register, and a pointer * to the table header on success. */ -struct ctl_table_header *register_sysctl_table(struct ctl_table * table) +struct ctl_table_header *__register_sysctl_paths( + struct ctl_table_root *root, + struct nsproxy *namespaces, + const struct ctl_path *path, struct ctl_table *table) { - struct ctl_table_header *tmp; - tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL); - if (!tmp) + struct list_head *header_list; + struct ctl_table_header *header; + struct ctl_table *new, **prevp; + unsigned int n, npath; + + /* Count the path components */ + for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath) + ; + + /* + * For each path component, allocate a 2-element ctl_table array. + * The first array element will be filled with the sysctl entry + * for this, the second will be the sentinel (ctl_name == 0). + * + * We allocate everything in one go so that we don't have to + * worry about freeing additional memory in unregister_sysctl_table. + */ + header = kzalloc(sizeof(struct ctl_table_header) + + (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL); + if (!header) return NULL; - tmp->ctl_table = table; - INIT_LIST_HEAD(&tmp->ctl_entry); - tmp->used = 0; - tmp->unregistering = NULL; - sysctl_set_parent(NULL, table); - if (sysctl_check_table(tmp->ctl_table)) { - kfree(tmp); + + new = (struct ctl_table *) (header + 1); + + /* Now connect the dots */ + prevp = &header->ctl_table; + for (n = 0; n < npath; ++n, ++path) { + /* Copy the procname */ + new->procname = path->procname; + new->ctl_name = path->ctl_name; + new->mode = 0555; + + *prevp = new; + prevp = &new->child; + + new += 2; + } + *prevp = table; + header->ctl_table_arg = table; + + INIT_LIST_HEAD(&header->ctl_entry); + header->used = 0; + header->unregistering = NULL; + header->root = root; + sysctl_set_parent(NULL, header->ctl_table); + if (sysctl_check_table(namespaces, header->ctl_table)) { + kfree(header); return NULL; } spin_lock(&sysctl_lock); - list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); + header_list = lookup_header_list(root, namespaces); + list_add_tail(&header->ctl_entry, header_list); spin_unlock(&sysctl_lock); - return tmp; + + return header; +} + +/** + * register_sysctl_table_path - register a sysctl table hierarchy + * @path: The path to the directory the sysctl table is in. + * @table: the top-level table structure + * + * Register a sysctl table hierarchy. @table should be a filled in ctl_table + * array. A completely 0 filled entry terminates the table. + * + * See __register_sysctl_paths for more details. + */ +struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path, + struct ctl_table *table) +{ + return __register_sysctl_paths(&sysctl_table_root, current->nsproxy, + path, table); +} + +/** + * register_sysctl_table - register a sysctl table hierarchy + * @table: the top-level table structure + * + * Register a sysctl table hierarchy. @table should be a filled in ctl_table + * array. A completely 0 filled entry terminates the table. + * + * See register_sysctl_paths for more details. + */ +struct ctl_table_header *register_sysctl_table(struct ctl_table *table) +{ + static const struct ctl_path null_path[] = { {} }; + + return register_sysctl_paths(null_path, table); } /** @@ -1604,6 +1804,12 @@ struct ctl_table_header *register_sysctl_table(struct ctl_table * table) return NULL; } +struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path, + struct ctl_table *table) +{ + return NULL; +} + void unregister_sysctl_table(struct ctl_table_header * table) { } @@ -1889,26 +2095,6 @@ static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp, return 0; } -#ifdef CONFIG_SECURITY_CAPABILITIES -/* - * init may raise the set. - */ - -int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - int op; - - if (write && !capable(CAP_SYS_MODULE)) { - return -EPERM; - } - - op = is_global_init(current) ? OP_SET : OP_AND; - return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, - do_proc_dointvec_bset_conv,&op); -} -#endif /* def CONFIG_SECURITY_CAPABILITIES */ - /* * Taint values can only be increased */ @@ -2322,12 +2508,6 @@ int proc_dointvec(struct ctl_table *table, int write, struct file *filp, return -ENOSYS; } -int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - return -ENOSYS; -} - int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) { @@ -2662,6 +2842,7 @@ EXPORT_SYMBOL(proc_dostring); EXPORT_SYMBOL(proc_doulongvec_minmax); EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); EXPORT_SYMBOL(register_sysctl_table); +EXPORT_SYMBOL(register_sysctl_paths); EXPORT_SYMBOL(sysctl_intvec); EXPORT_SYMBOL(sysctl_jiffies); EXPORT_SYMBOL(sysctl_ms_jiffies); diff --git a/kernel/sysctl_check.c b/kernel/sysctl_check.c index bed939f82c3..006365b69ea 100644 --- a/kernel/sysctl_check.c +++ b/kernel/sysctl_check.c @@ -1,6 +1,5 @@ #include <linux/stat.h> #include <linux/sysctl.h> -#include "../arch/s390/appldata/appldata.h" #include "../fs/xfs/linux-2.6/xfs_sysctl.h" #include <linux/sunrpc/debug.h> #include <linux/string.h> @@ -38,10 +37,6 @@ static struct trans_ctl_table trans_kern_table[] = { { KERN_NODENAME, "hostname" }, { KERN_DOMAINNAME, "domainname" }, -#ifdef CONFIG_SECURITY_CAPABILITIES - { KERN_CAP_BSET, "cap-bound" }, -#endif /* def CONFIG_SECURITY_CAPABILITIES */ - { KERN_PANIC, "panic" }, { KERN_REALROOTDEV, "real-root-dev" }, @@ -428,7 +423,7 @@ static struct trans_ctl_table trans_net_netrom_table[] = { {} }; -static struct trans_ctl_table trans_net_ax25_table[] = { +static struct trans_ctl_table trans_net_ax25_param_table[] = { { NET_AX25_IP_DEFAULT_MODE, "ip_default_mode" }, { NET_AX25_DEFAULT_MODE, "ax25_default_mode" }, { NET_AX25_BACKOFF_TYPE, "backoff_type" }, @@ -446,6 +441,11 @@ static struct trans_ctl_table trans_net_ax25_table[] = { {} }; +static struct trans_ctl_table trans_net_ax25_table[] = { + { 0, NULL, trans_net_ax25_param_table }, + {} +}; + static struct trans_ctl_table trans_net_bridge_table[] = { { NET_BRIDGE_NF_CALL_ARPTABLES, "bridge-nf-call-arptables" }, { NET_BRIDGE_NF_CALL_IPTABLES, "bridge-nf-call-iptables" }, @@ -1338,7 +1338,8 @@ static void sysctl_repair_table(struct ctl_table *table) } } -static struct ctl_table *sysctl_check_lookup(struct ctl_table *table) +static struct ctl_table *sysctl_check_lookup(struct nsproxy *namespaces, + struct ctl_table *table) { struct ctl_table_header *head; struct ctl_table *ref, *test; @@ -1346,8 +1347,8 @@ static struct ctl_table *sysctl_check_lookup(struct ctl_table *table) depth = sysctl_depth(table); - for (head = sysctl_head_next(NULL); head; - head = sysctl_head_next(head)) { + for (head = __sysctl_head_next(namespaces, NULL); head; + head = __sysctl_head_next(namespaces, head)) { cur_depth = depth; ref = head->ctl_table; repeat: @@ -1392,13 +1393,14 @@ static void set_fail(const char **fail, struct ctl_table *table, const char *str *fail = str; } -static int sysctl_check_dir(struct ctl_table *table) +static int sysctl_check_dir(struct nsproxy *namespaces, + struct ctl_table *table) { struct ctl_table *ref; int error; error = 0; - ref = sysctl_check_lookup(table); + ref = sysctl_check_lookup(namespaces, table); if (ref) { int match = 0; if ((!table->procname && !ref->procname) || @@ -1423,11 +1425,12 @@ static int sysctl_check_dir(struct ctl_table *table) return error; } -static void sysctl_check_leaf(struct ctl_table *table, const char **fail) +static void sysctl_check_leaf(struct nsproxy *namespaces, + struct ctl_table *table, const char **fail) { struct ctl_table *ref; - ref = sysctl_check_lookup(table); + ref = sysctl_check_lookup(namespaces, table); if (ref && (ref != table)) set_fail(fail, table, "Sysctl already exists"); } @@ -1451,7 +1454,7 @@ static void sysctl_check_bin_path(struct ctl_table *table, const char **fail) } } -int sysctl_check_table(struct ctl_table *table) +int sysctl_check_table(struct nsproxy *namespaces, struct ctl_table *table) { int error = 0; for (; table->ctl_name || table->procname; table++) { @@ -1481,7 +1484,7 @@ int sysctl_check_table(struct ctl_table *table) set_fail(&fail, table, "Directory with extra1"); if (table->extra2) set_fail(&fail, table, "Directory with extra2"); - if (sysctl_check_dir(table)) + if (sysctl_check_dir(namespaces, table)) set_fail(&fail, table, "Inconsistent directory names"); } else { if ((table->strategy == sysctl_data) || @@ -1491,9 +1494,6 @@ int sysctl_check_table(struct ctl_table *table) (table->strategy == sysctl_ms_jiffies) || (table->proc_handler == proc_dostring) || (table->proc_handler == proc_dointvec) || -#ifdef CONFIG_SECURITY_CAPABILITIES - (table->proc_handler == proc_dointvec_bset) || -#endif /* def CONFIG_SECURITY_CAPABILITIES */ (table->proc_handler == proc_dointvec_minmax) || (table->proc_handler == proc_dointvec_jiffies) || (table->proc_handler == proc_dointvec_userhz_jiffies) || @@ -1530,7 +1530,7 @@ int sysctl_check_table(struct ctl_table *table) if (!table->procname && table->proc_handler) set_fail(&fail, table, "proc_handler without procname"); #endif - sysctl_check_leaf(table, &fail); + sysctl_check_leaf(namespaces, table, &fail); } sysctl_check_bin_path(table, &fail); if (fail) { @@ -1538,7 +1538,7 @@ int sysctl_check_table(struct ctl_table *table) error = -EINVAL; } if (table->child) - error |= sysctl_check_table(table->child); + error |= sysctl_check_table(namespaces, table->child); } return error; } diff --git a/kernel/test_kprobes.c b/kernel/test_kprobes.c new file mode 100644 index 00000000000..06b6395b45b --- /dev/null +++ b/kernel/test_kprobes.c @@ -0,0 +1,228 @@ +/* + * test_kprobes.c - simple sanity test for *probes + * + * Copyright IBM Corp. 2008 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it would be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/kprobes.h> +#include <linux/random.h> + +#define div_factor 3 + +static u32 rand1, preh_val, posth_val, jph_val; +static int errors, handler_errors, num_tests; + +static noinline u32 kprobe_target(u32 value) +{ + /* + * gcc ignores noinline on some architectures unless we stuff + * sufficient lard into the function. The get_kprobe() here is + * just for that. + * + * NOTE: We aren't concerned about the correctness of get_kprobe() + * here; hence, this call is neither under !preempt nor with the + * kprobe_mutex held. This is fine(tm) + */ + if (get_kprobe((void *)0xdeadbeef)) + printk(KERN_INFO "Kprobe smoke test: probe on 0xdeadbeef!\n"); + + return (value / div_factor); +} + +static int kp_pre_handler(struct kprobe *p, struct pt_regs *regs) +{ + preh_val = (rand1 / div_factor); + return 0; +} + +static void kp_post_handler(struct kprobe *p, struct pt_regs *regs, + unsigned long flags) +{ + if (preh_val != (rand1 / div_factor)) { + handler_errors++; + printk(KERN_ERR "Kprobe smoke test failed: " + "incorrect value in post_handler\n"); + } + posth_val = preh_val + div_factor; +} + +static struct kprobe kp = { + .symbol_name = "kprobe_target", + .pre_handler = kp_pre_handler, + .post_handler = kp_post_handler +}; + +static int test_kprobe(void) +{ + int ret; + + ret = register_kprobe(&kp); + if (ret < 0) { + printk(KERN_ERR "Kprobe smoke test failed: " + "register_kprobe returned %d\n", ret); + return ret; + } + + ret = kprobe_target(rand1); + unregister_kprobe(&kp); + + if (preh_val == 0) { + printk(KERN_ERR "Kprobe smoke test failed: " + "kprobe pre_handler not called\n"); + handler_errors++; + } + + if (posth_val == 0) { + printk(KERN_ERR "Kprobe smoke test failed: " + "kprobe post_handler not called\n"); + handler_errors++; + } + + return 0; +} + +static u32 j_kprobe_target(u32 value) +{ + if (value != rand1) { + handler_errors++; + printk(KERN_ERR "Kprobe smoke test failed: " + "incorrect value in jprobe handler\n"); + } + + jph_val = rand1; + jprobe_return(); + return 0; +} + +static struct jprobe jp = { + .entry = j_kprobe_target, + .kp.symbol_name = "kprobe_target" +}; + +static int test_jprobe(void) +{ + int ret; + + ret = register_jprobe(&jp); + if (ret < 0) { + printk(KERN_ERR "Kprobe smoke test failed: " + "register_jprobe returned %d\n", ret); + return ret; + } + + ret = kprobe_target(rand1); + unregister_jprobe(&jp); + if (jph_val == 0) { + printk(KERN_ERR "Kprobe smoke test failed: " + "jprobe handler not called\n"); + handler_errors++; + } + + return 0; +} + +#ifdef CONFIG_KRETPROBES +static u32 krph_val; + +static int entry_handler(struct kretprobe_instance *ri, struct pt_regs *regs) +{ + krph_val = (rand1 / div_factor); + return 0; +} + +static int return_handler(struct kretprobe_instance *ri, struct pt_regs *regs) +{ + unsigned long ret = regs_return_value(regs); + + if (ret != (rand1 / div_factor)) { + handler_errors++; + printk(KERN_ERR "Kprobe smoke test failed: " + "incorrect value in kretprobe handler\n"); + } + if (krph_val == 0) { + handler_errors++; + printk(KERN_ERR "Kprobe smoke test failed: " + "call to kretprobe entry handler failed\n"); + } + + krph_val = rand1; + return 0; +} + +static struct kretprobe rp = { + .handler = return_handler, + .entry_handler = entry_handler, + .kp.symbol_name = "kprobe_target" +}; + +static int test_kretprobe(void) +{ + int ret; + + ret = register_kretprobe(&rp); + if (ret < 0) { + printk(KERN_ERR "Kprobe smoke test failed: " + "register_kretprobe returned %d\n", ret); + return ret; + } + + ret = kprobe_target(rand1); + unregister_kretprobe(&rp); + if (krph_val != rand1) { + printk(KERN_ERR "Kprobe smoke test failed: " + "kretprobe handler not called\n"); + handler_errors++; + } + + return 0; +} +#endif /* CONFIG_KRETPROBES */ + +int init_test_probes(void) +{ + int ret; + + do { + rand1 = random32(); + } while (rand1 <= div_factor); + + printk(KERN_INFO "Kprobe smoke test started\n"); + num_tests++; + ret = test_kprobe(); + if (ret < 0) + errors++; + + num_tests++; + ret = test_jprobe(); + if (ret < 0) + errors++; + +#ifdef CONFIG_KRETPROBES + num_tests++; + ret = test_kretprobe(); + if (ret < 0) + errors++; +#endif /* CONFIG_KRETPROBES */ + + if (errors) + printk(KERN_ERR "BUG: Kprobe smoke test: %d out of " + "%d tests failed\n", errors, num_tests); + else if (handler_errors) + printk(KERN_ERR "BUG: Kprobe smoke test: %d error(s) " + "running handlers\n", handler_errors); + else + printk(KERN_INFO "Kprobe smoke test passed successfully\n"); + + return 0; +} diff --git a/kernel/time.c b/kernel/time.c index 09d3c45c4da..33af3e55570 100644 --- a/kernel/time.c +++ b/kernel/time.c @@ -129,6 +129,7 @@ static inline void warp_clock(void) write_seqlock_irq(&xtime_lock); wall_to_monotonic.tv_sec -= sys_tz.tz_minuteswest * 60; xtime.tv_sec += sys_tz.tz_minuteswest * 60; + update_xtime_cache(0); write_sequnlock_irq(&xtime_lock); clock_was_set(); } @@ -565,7 +566,11 @@ EXPORT_SYMBOL(jiffies_to_timeval); clock_t jiffies_to_clock_t(long x) { #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 +# if HZ < USER_HZ + return x * (USER_HZ / HZ); +# else return x / (HZ / USER_HZ); +# endif #else u64 tmp = (u64)x * TICK_NSEC; do_div(tmp, (NSEC_PER_SEC / USER_HZ)); @@ -598,7 +603,14 @@ EXPORT_SYMBOL(clock_t_to_jiffies); u64 jiffies_64_to_clock_t(u64 x) { #if (TICK_NSEC % (NSEC_PER_SEC / USER_HZ)) == 0 +# if HZ < USER_HZ + x *= USER_HZ; + do_div(x, HZ); +# elif HZ > USER_HZ do_div(x, HZ / USER_HZ); +# else + /* Nothing to do */ +# endif #else /* * There are better ways that don't overflow early, @@ -610,7 +622,6 @@ u64 jiffies_64_to_clock_t(u64 x) #endif return x; } - EXPORT_SYMBOL(jiffies_64_to_clock_t); u64 nsec_to_clock_t(u64 x) @@ -645,7 +656,6 @@ u64 get_jiffies_64(void) } while (read_seqretry(&xtime_lock, seq)); return ret; } - EXPORT_SYMBOL(get_jiffies_64); #endif diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index 5fb139fef9f..3e59fce6dd4 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -41,6 +41,11 @@ unsigned long clockevent_delta2ns(unsigned long latch, { u64 clc = ((u64) latch << evt->shift); + if (unlikely(!evt->mult)) { + evt->mult = 1; + WARN_ON(1); + } + do_div(clc, evt->mult); if (clc < 1000) clc = 1000; @@ -151,6 +156,14 @@ static void clockevents_notify_released(void) void clockevents_register_device(struct clock_event_device *dev) { BUG_ON(dev->mode != CLOCK_EVT_MODE_UNUSED); + /* + * A nsec2cyc multiplicator of 0 is invalid and we'd crash + * on it, so fix it up and emit a warning: + */ + if (unlikely(!dev->mult)) { + dev->mult = 1; + WARN_ON(1); + } spin_lock(&clockevents_lock); diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index c8a9d13874d..81afb3927ec 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -142,8 +142,13 @@ static void clocksource_watchdog(unsigned long data) } if (!list_empty(&watchdog_list)) { - __mod_timer(&watchdog_timer, - watchdog_timer.expires + WATCHDOG_INTERVAL); + /* Cycle through CPUs to check if the CPUs stay synchronized to + * each other. */ + int next_cpu = next_cpu(raw_smp_processor_id(), cpu_online_map); + if (next_cpu >= NR_CPUS) + next_cpu = first_cpu(cpu_online_map); + watchdog_timer.expires += WATCHDOG_INTERVAL; + add_timer_on(&watchdog_timer, next_cpu); } spin_unlock(&watchdog_lock); } @@ -165,7 +170,7 @@ static void clocksource_check_watchdog(struct clocksource *cs) if (!started && watchdog) { watchdog_last = watchdog->read(); watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL; - add_timer(&watchdog_timer); + add_timer_on(&watchdog_timer, first_cpu(cpu_online_map)); } } else { if (cs->flags & CLOCK_SOURCE_IS_CONTINUOUS) @@ -175,7 +180,7 @@ static void clocksource_check_watchdog(struct clocksource *cs) if (watchdog) del_timer(&watchdog_timer); watchdog = cs; - init_timer(&watchdog_timer); + init_timer_deferrable(&watchdog_timer); watchdog_timer.function = clocksource_watchdog; /* Reset watchdog cycles */ @@ -186,7 +191,8 @@ static void clocksource_check_watchdog(struct clocksource *cs) watchdog_last = watchdog->read(); watchdog_timer.expires = jiffies + WATCHDOG_INTERVAL; - add_timer(&watchdog_timer); + add_timer_on(&watchdog_timer, + first_cpu(cpu_online_map)); } } } @@ -331,6 +337,21 @@ void clocksource_change_rating(struct clocksource *cs, int rating) spin_unlock_irqrestore(&clocksource_lock, flags); } +/** + * clocksource_unregister - remove a registered clocksource + */ +void clocksource_unregister(struct clocksource *cs) +{ + unsigned long flags; + + spin_lock_irqsave(&clocksource_lock, flags); + list_del(&cs->list); + if (clocksource_override == cs) + clocksource_override = NULL; + next_clocksource = select_clocksource(); + spin_unlock_irqrestore(&clocksource_lock, flags); +} + #ifdef CONFIG_SYSFS /** * sysfs_show_current_clocksources - sysfs interface for current clocksource @@ -342,15 +363,13 @@ void clocksource_change_rating(struct clocksource *cs, int rating) static ssize_t sysfs_show_current_clocksources(struct sys_device *dev, char *buf) { - char *curr = buf; + ssize_t count = 0; spin_lock_irq(&clocksource_lock); - curr += sprintf(curr, "%s ", curr_clocksource->name); + count = snprintf(buf, PAGE_SIZE, "%s\n", curr_clocksource->name); spin_unlock_irq(&clocksource_lock); - curr += sprintf(curr, "\n"); - - return curr - buf; + return count; } /** @@ -418,17 +437,20 @@ static ssize_t sysfs_show_available_clocksources(struct sys_device *dev, char *buf) { struct clocksource *src; - char *curr = buf; + ssize_t count = 0; spin_lock_irq(&clocksource_lock); list_for_each_entry(src, &clocksource_list, list) { - curr += sprintf(curr, "%s ", src->name); + count += snprintf(buf + count, + max((ssize_t)PAGE_SIZE - count, (ssize_t)0), + "%s ", src->name); } spin_unlock_irq(&clocksource_lock); - curr += sprintf(curr, "\n"); + count += snprintf(buf + count, + max((ssize_t)PAGE_SIZE - count, (ssize_t)0), "\n"); - return curr - buf; + return count; } /* @@ -441,7 +463,7 @@ static SYSDEV_ATTR(available_clocksource, 0600, sysfs_show_available_clocksources, NULL); static struct sysdev_class clocksource_sysclass = { - set_kset_name("clocksource"), + .name = "clocksource", }; static struct sys_device device_clocksource = { diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index aa82d7bf478..e1bd50cbbf5 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -126,9 +126,9 @@ int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu) /* * Broadcast the event to the cpus, which are set in the mask */ -int tick_do_broadcast(cpumask_t mask) +static void tick_do_broadcast(cpumask_t mask) { - int ret = 0, cpu = smp_processor_id(); + int cpu = smp_processor_id(); struct tick_device *td; /* @@ -138,7 +138,6 @@ int tick_do_broadcast(cpumask_t mask) cpu_clear(cpu, mask); td = &per_cpu(tick_cpu_device, cpu); td->evtdev->event_handler(td->evtdev); - ret = 1; } if (!cpus_empty(mask)) { @@ -151,9 +150,7 @@ int tick_do_broadcast(cpumask_t mask) cpu = first_cpu(mask); td = &per_cpu(tick_cpu_device, cpu); td->evtdev->broadcast(mask); - ret = 1; } - return ret; } /* @@ -384,45 +381,19 @@ int tick_resume_broadcast_oneshot(struct clock_event_device *bc) } /* - * Reprogram the broadcast device: - * - * Called with tick_broadcast_lock held and interrupts disabled. - */ -static int tick_broadcast_reprogram(void) -{ - ktime_t expires = { .tv64 = KTIME_MAX }; - struct tick_device *td; - int cpu; - - /* - * Find the event which expires next: - */ - for (cpu = first_cpu(tick_broadcast_oneshot_mask); cpu != NR_CPUS; - cpu = next_cpu(cpu, tick_broadcast_oneshot_mask)) { - td = &per_cpu(tick_cpu_device, cpu); - if (td->evtdev->next_event.tv64 < expires.tv64) - expires = td->evtdev->next_event; - } - - if (expires.tv64 == KTIME_MAX) - return 0; - - return tick_broadcast_set_event(expires, 0); -} - -/* * Handle oneshot mode broadcasting */ static void tick_handle_oneshot_broadcast(struct clock_event_device *dev) { struct tick_device *td; cpumask_t mask; - ktime_t now; + ktime_t now, next_event; int cpu; spin_lock(&tick_broadcast_lock); again: dev->next_event.tv64 = KTIME_MAX; + next_event.tv64 = KTIME_MAX; mask = CPU_MASK_NONE; now = ktime_get(); /* Find all expired events */ @@ -431,19 +402,31 @@ again: td = &per_cpu(tick_cpu_device, cpu); if (td->evtdev->next_event.tv64 <= now.tv64) cpu_set(cpu, mask); + else if (td->evtdev->next_event.tv64 < next_event.tv64) + next_event.tv64 = td->evtdev->next_event.tv64; } /* - * Wakeup the cpus which have an expired event. The broadcast - * device is reprogrammed in the return from idle code. + * Wakeup the cpus which have an expired event. + */ + tick_do_broadcast(mask); + + /* + * Two reasons for reprogram: + * + * - The global event did not expire any CPU local + * events. This happens in dyntick mode, as the maximum PIT + * delta is quite small. + * + * - There are pending events on sleeping CPUs which were not + * in the event mask */ - if (!tick_do_broadcast(mask)) { + if (next_event.tv64 != KTIME_MAX) { /* - * The global event did not expire any CPU local - * events. This happens in dyntick mode, as the - * maximum PIT delta is quite small. + * Rearm the broadcast device. If event expired, + * repeat the above */ - if (tick_broadcast_reprogram()) + if (tick_broadcast_set_event(next_event, 0)) goto again; } spin_unlock(&tick_broadcast_lock); diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index bb13f272490..f13f2b7f4fd 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -70,8 +70,6 @@ static inline int tick_resume_broadcast_oneshot(struct clock_event_device *bc) * Broadcasting support */ #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST -extern int tick_do_broadcast(cpumask_t mask); - extern int tick_device_uses_broadcast(struct clock_event_device *dev, int cpu); extern int tick_check_broadcast_device(struct clock_event_device *dev); extern int tick_is_broadcast_device(struct clock_event_device *dev); diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index cb89fa8db11..88267f0a847 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -9,7 +9,7 @@ * * Started by: Thomas Gleixner and Ingo Molnar * - * For licencing details see kernel-base/COPYING + * Distribute under GPLv2. */ #include <linux/cpu.h> #include <linux/err.h> @@ -137,12 +137,51 @@ void tick_nohz_update_jiffies(void) cpu_clear(cpu, nohz_cpu_mask); now = ktime_get(); + ts->idle_waketime = now; local_irq_save(flags); tick_do_update_jiffies64(now); local_irq_restore(flags); } +void tick_nohz_stop_idle(int cpu) +{ + struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + + if (ts->idle_active) { + ktime_t now, delta; + now = ktime_get(); + delta = ktime_sub(now, ts->idle_entrytime); + ts->idle_lastupdate = now; + ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); + ts->idle_active = 0; + } +} + +static ktime_t tick_nohz_start_idle(int cpu) +{ + struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + ktime_t now, delta; + + now = ktime_get(); + if (ts->idle_active) { + delta = ktime_sub(now, ts->idle_entrytime); + ts->idle_lastupdate = now; + ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); + } + ts->idle_entrytime = now; + ts->idle_active = 1; + return now; +} + +u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time) +{ + struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); + + *last_update_time = ktime_to_us(ts->idle_lastupdate); + return ktime_to_us(ts->idle_sleeptime); +} + /** * tick_nohz_stop_sched_tick - stop the idle tick from the idle task * @@ -153,14 +192,16 @@ void tick_nohz_update_jiffies(void) void tick_nohz_stop_sched_tick(void) { unsigned long seq, last_jiffies, next_jiffies, delta_jiffies, flags; + unsigned long rt_jiffies; struct tick_sched *ts; - ktime_t last_update, expires, now, delta; + ktime_t last_update, expires, now; struct clock_event_device *dev = __get_cpu_var(tick_cpu_device).evtdev; int cpu; local_irq_save(flags); cpu = smp_processor_id(); + now = tick_nohz_start_idle(cpu); ts = &per_cpu(tick_cpu_sched, cpu); /* @@ -192,19 +233,7 @@ void tick_nohz_stop_sched_tick(void) } } - now = ktime_get(); - /* - * When called from irq_exit we need to account the idle sleep time - * correctly. - */ - if (ts->tick_stopped) { - delta = ktime_sub(now, ts->idle_entrytime); - ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); - } - - ts->idle_entrytime = now; ts->idle_calls++; - /* Read jiffies and the time when jiffies were updated last */ do { seq = read_seqbegin(&xtime_lock); @@ -216,6 +245,10 @@ void tick_nohz_stop_sched_tick(void) next_jiffies = get_next_timer_interrupt(last_jiffies); delta_jiffies = next_jiffies - last_jiffies; + rt_jiffies = rt_needs_cpu(cpu); + if (rt_jiffies && rt_jiffies < delta_jiffies) + delta_jiffies = rt_jiffies; + if (rcu_needs_cpu(cpu)) delta_jiffies = 1; /* @@ -291,7 +324,7 @@ void tick_nohz_stop_sched_tick(void) /* Check, if the timer was already in the past */ if (hrtimer_active(&ts->sched_timer)) goto out; - } else if(!tick_program_event(expires, 0)) + } else if (!tick_program_event(expires, 0)) goto out; /* * We are past the event already. So we crossed a @@ -332,23 +365,22 @@ void tick_nohz_restart_sched_tick(void) int cpu = smp_processor_id(); struct tick_sched *ts = &per_cpu(tick_cpu_sched, cpu); unsigned long ticks; - ktime_t now, delta; + ktime_t now; - if (!ts->tick_stopped) + local_irq_disable(); + tick_nohz_stop_idle(cpu); + + if (!ts->tick_stopped) { + local_irq_enable(); return; + } /* Update jiffies first */ - now = ktime_get(); - - local_irq_disable(); select_nohz_load_balancer(0); + now = ktime_get(); tick_do_update_jiffies64(now); cpu_clear(cpu, nohz_cpu_mask); - /* Account the idle time */ - delta = ktime_sub(now, ts->idle_entrytime); - ts->idle_sleeptime = ktime_add(ts->idle_sleeptime, delta); - /* * We stopped the tick in idle. Update process times would miss the * time we slept as update_process_times does only a 1 tick @@ -369,6 +401,7 @@ void tick_nohz_restart_sched_tick(void) * Cancel the scheduled timer and restore the tick */ ts->tick_stopped = 0; + ts->idle_exittime = now; hrtimer_cancel(&ts->sched_timer); ts->sched_timer.expires = ts->idle_tick; @@ -502,14 +535,13 @@ static inline void tick_nohz_switch_to_nohz(void) { } */ #ifdef CONFIG_HIGH_RES_TIMERS /* - * We rearm the timer until we get disabled by the idle code + * We rearm the timer until we get disabled by the idle code. * Called with interrupts disabled and timer->base->cpu_base->lock held. */ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) { struct tick_sched *ts = container_of(timer, struct tick_sched, sched_timer); - struct hrtimer_cpu_base *base = timer->base->cpu_base; struct pt_regs *regs = get_irq_regs(); ktime_t now = ktime_get(); int cpu = smp_processor_id(); @@ -547,15 +579,8 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) touch_softlockup_watchdog(); ts->idle_jiffies++; } - /* - * update_process_times() might take tasklist_lock, hence - * drop the base lock. sched-tick hrtimers are per-CPU and - * never accessible by userspace APIs, so this is safe to do. - */ - spin_unlock(&base->lock); update_process_times(user_mode(regs)); profile_tick(CPU_PROFILING); - spin_lock(&base->lock); } /* Do not restart, when we are in the idle loop */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index e5e466b2759..cd5dbc4579c 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -47,7 +47,7 @@ struct timespec wall_to_monotonic __attribute__ ((aligned (16))); static unsigned long total_sleep_time; /* seconds */ static struct timespec xtime_cache __attribute__ ((aligned (16))); -static inline void update_xtime_cache(u64 nsec) +void update_xtime_cache(u64 nsec) { xtime_cache = xtime; timespec_add_ns(&xtime_cache, nsec); @@ -82,13 +82,12 @@ static inline s64 __get_nsec_offset(void) } /** - * __get_realtime_clock_ts - Returns the time of day in a timespec + * getnstimeofday - Returns the time of day in a timespec * @ts: pointer to the timespec to be set * - * Returns the time of day in a timespec. Used by - * do_gettimeofday() and get_realtime_clock_ts(). + * Returns the time of day in a timespec. */ -static inline void __get_realtime_clock_ts(struct timespec *ts) +void getnstimeofday(struct timespec *ts) { unsigned long seq; s64 nsecs; @@ -104,30 +103,19 @@ static inline void __get_realtime_clock_ts(struct timespec *ts) timespec_add_ns(ts, nsecs); } -/** - * getnstimeofday - Returns the time of day in a timespec - * @ts: pointer to the timespec to be set - * - * Returns the time of day in a timespec. - */ -void getnstimeofday(struct timespec *ts) -{ - __get_realtime_clock_ts(ts); -} - EXPORT_SYMBOL(getnstimeofday); /** * do_gettimeofday - Returns the time of day in a timeval * @tv: pointer to the timeval to be set * - * NOTE: Users should be converted to using get_realtime_clock_ts() + * NOTE: Users should be converted to using getnstimeofday() */ void do_gettimeofday(struct timeval *tv) { struct timespec now; - __get_realtime_clock_ts(&now); + getnstimeofday(&now); tv->tv_sec = now.tv_sec; tv->tv_usec = now.tv_nsec/1000; } @@ -157,6 +145,7 @@ int do_settimeofday(struct timespec *tv) set_normalized_timespec(&xtime, sec, nsec); set_normalized_timespec(&wall_to_monotonic, wtm_sec, wtm_nsec); + update_xtime_cache(0); clock->error = 0; ntp_clear(); @@ -198,7 +187,8 @@ static void change_clocksource(void) clock->error = 0; clock->xtime_nsec = 0; - clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); + clocksource_calculate_interval(clock, + (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT)); tick_clock_notify(); @@ -255,15 +245,16 @@ void __init timekeeping_init(void) ntp_clear(); clock = clocksource_get_next(); - clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH); + clocksource_calculate_interval(clock, + (unsigned long)(current_tick_length()>>TICK_LENGTH_SHIFT)); clock->cycle_last = clocksource_read(clock); xtime.tv_sec = sec; xtime.tv_nsec = 0; set_normalized_timespec(&wall_to_monotonic, -xtime.tv_sec, -xtime.tv_nsec); + update_xtime_cache(0); total_sleep_time = 0; - write_sequnlock_irqrestore(&xtime_lock, flags); } @@ -300,6 +291,7 @@ static int timekeeping_resume(struct sys_device *dev) } /* Make sure that we have the correct xtime reference */ timespec_add_ns(&xtime, timekeeping_suspend_nsecs); + update_xtime_cache(0); /* re-base the last cycle value */ clock->cycle_last = clocksource_read(clock); clock->error = 0; @@ -335,9 +327,9 @@ static int timekeeping_suspend(struct sys_device *dev, pm_message_t state) /* sysfs resume/suspend bits for timekeeping */ static struct sysdev_class timekeeping_sysclass = { + .name = "timekeeping", .resume = timekeeping_resume, .suspend = timekeeping_suspend, - set_kset_name("timekeeping"), }; static struct sys_device device_timer = { diff --git a/kernel/time/timer_list.c b/kernel/time/timer_list.c index 12c5f4cb6b8..d3d94c1a0fd 100644 --- a/kernel/time/timer_list.c +++ b/kernel/time/timer_list.c @@ -166,6 +166,8 @@ static void print_cpu(struct seq_file *m, int cpu, u64 now) P(idle_calls); P(idle_sleeps); P_ns(idle_entrytime); + P_ns(idle_waketime); + P_ns(idle_exittime); P_ns(idle_sleeptime); P(last_jiffies); P(next_jiffies); diff --git a/kernel/time/timer_stats.c b/kernel/time/timer_stats.c index c36bb7ed030..417da8c5bc7 100644 --- a/kernel/time/timer_stats.c +++ b/kernel/time/timer_stats.c @@ -26,7 +26,7 @@ * the pid and cmdline from the owner process if applicable. * * Start/stop data collection: - * # echo 1[0] >/proc/timer_stats + * # echo [1|0] >/proc/timer_stats * * Display the information collected so far: * # cat /proc/timer_stats diff --git a/kernel/timer.c b/kernel/timer.c index a05817c021d..70b29b59343 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -58,59 +58,57 @@ EXPORT_SYMBOL(jiffies_64); #define TVN_MASK (TVN_SIZE - 1) #define TVR_MASK (TVR_SIZE - 1) -typedef struct tvec_s { +struct tvec { struct list_head vec[TVN_SIZE]; -} tvec_t; +}; -typedef struct tvec_root_s { +struct tvec_root { struct list_head vec[TVR_SIZE]; -} tvec_root_t; +}; -struct tvec_t_base_s { +struct tvec_base { spinlock_t lock; struct timer_list *running_timer; unsigned long timer_jiffies; - tvec_root_t tv1; - tvec_t tv2; - tvec_t tv3; - tvec_t tv4; - tvec_t tv5; + struct tvec_root tv1; + struct tvec tv2; + struct tvec tv3; + struct tvec tv4; + struct tvec tv5; } ____cacheline_aligned; -typedef struct tvec_t_base_s tvec_base_t; - -tvec_base_t boot_tvec_bases; +struct tvec_base boot_tvec_bases; EXPORT_SYMBOL(boot_tvec_bases); -static DEFINE_PER_CPU(tvec_base_t *, tvec_bases) = &boot_tvec_bases; +static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases; /* - * Note that all tvec_bases is 2 byte aligned and lower bit of + * Note that all tvec_bases are 2 byte aligned and lower bit of * base in timer_list is guaranteed to be zero. Use the LSB for * the new flag to indicate whether the timer is deferrable */ #define TBASE_DEFERRABLE_FLAG (0x1) /* Functions below help us manage 'deferrable' flag */ -static inline unsigned int tbase_get_deferrable(tvec_base_t *base) +static inline unsigned int tbase_get_deferrable(struct tvec_base *base) { return ((unsigned int)(unsigned long)base & TBASE_DEFERRABLE_FLAG); } -static inline tvec_base_t *tbase_get_base(tvec_base_t *base) +static inline struct tvec_base *tbase_get_base(struct tvec_base *base) { - return ((tvec_base_t *)((unsigned long)base & ~TBASE_DEFERRABLE_FLAG)); + return ((struct tvec_base *)((unsigned long)base & ~TBASE_DEFERRABLE_FLAG)); } static inline void timer_set_deferrable(struct timer_list *timer) { - timer->base = ((tvec_base_t *)((unsigned long)(timer->base) | + timer->base = ((struct tvec_base *)((unsigned long)(timer->base) | TBASE_DEFERRABLE_FLAG)); } static inline void -timer_set_base(struct timer_list *timer, tvec_base_t *new_base) +timer_set_base(struct timer_list *timer, struct tvec_base *new_base) { - timer->base = (tvec_base_t *)((unsigned long)(new_base) | + timer->base = (struct tvec_base *)((unsigned long)(new_base) | tbase_get_deferrable(timer->base)); } @@ -246,7 +244,7 @@ unsigned long round_jiffies_relative(unsigned long j) EXPORT_SYMBOL_GPL(round_jiffies_relative); -static inline void set_running_timer(tvec_base_t *base, +static inline void set_running_timer(struct tvec_base *base, struct timer_list *timer) { #ifdef CONFIG_SMP @@ -254,7 +252,7 @@ static inline void set_running_timer(tvec_base_t *base, #endif } -static void internal_add_timer(tvec_base_t *base, struct timer_list *timer) +static void internal_add_timer(struct tvec_base *base, struct timer_list *timer) { unsigned long expires = timer->expires; unsigned long idx = expires - base->timer_jiffies; @@ -371,14 +369,14 @@ static inline void detach_timer(struct timer_list *timer, * possible to set timer->base = NULL and drop the lock: the timer remains * locked. */ -static tvec_base_t *lock_timer_base(struct timer_list *timer, +static struct tvec_base *lock_timer_base(struct timer_list *timer, unsigned long *flags) __acquires(timer->base->lock) { - tvec_base_t *base; + struct tvec_base *base; for (;;) { - tvec_base_t *prelock_base = timer->base; + struct tvec_base *prelock_base = timer->base; base = tbase_get_base(prelock_base); if (likely(base != NULL)) { spin_lock_irqsave(&base->lock, *flags); @@ -393,7 +391,7 @@ static tvec_base_t *lock_timer_base(struct timer_list *timer, int __mod_timer(struct timer_list *timer, unsigned long expires) { - tvec_base_t *base, *new_base; + struct tvec_base *base, *new_base; unsigned long flags; int ret = 0; @@ -445,7 +443,7 @@ EXPORT_SYMBOL(__mod_timer); */ void add_timer_on(struct timer_list *timer, int cpu) { - tvec_base_t *base = per_cpu(tvec_bases, cpu); + struct tvec_base *base = per_cpu(tvec_bases, cpu); unsigned long flags; timer_stats_timer_set_start_info(timer); @@ -508,7 +506,7 @@ EXPORT_SYMBOL(mod_timer); */ int del_timer(struct timer_list *timer) { - tvec_base_t *base; + struct tvec_base *base; unsigned long flags; int ret = 0; @@ -539,7 +537,7 @@ EXPORT_SYMBOL(del_timer); */ int try_to_del_timer_sync(struct timer_list *timer) { - tvec_base_t *base; + struct tvec_base *base; unsigned long flags; int ret = -1; @@ -591,7 +589,7 @@ int del_timer_sync(struct timer_list *timer) EXPORT_SYMBOL(del_timer_sync); #endif -static int cascade(tvec_base_t *base, tvec_t *tv, int index) +static int cascade(struct tvec_base *base, struct tvec *tv, int index) { /* cascade all the timers from tv up one level */ struct timer_list *timer, *tmp; @@ -620,7 +618,7 @@ static int cascade(tvec_base_t *base, tvec_t *tv, int index) * This function cascades all vectors and executes all expired timer * vectors. */ -static inline void __run_timers(tvec_base_t *base) +static inline void __run_timers(struct tvec_base *base) { struct timer_list *timer; @@ -657,7 +655,7 @@ static inline void __run_timers(tvec_base_t *base) int preempt_count = preempt_count(); fn(data); if (preempt_count != preempt_count()) { - printk(KERN_WARNING "huh, entered %p " + printk(KERN_ERR "huh, entered %p " "with preempt_count %08x, exited" " with %08x?\n", fn, preempt_count, @@ -678,13 +676,13 @@ static inline void __run_timers(tvec_base_t *base) * is used on S/390 to stop all activity when a cpus is idle. * This functions needs to be called disabled. */ -static unsigned long __next_timer_interrupt(tvec_base_t *base) +static unsigned long __next_timer_interrupt(struct tvec_base *base) { unsigned long timer_jiffies = base->timer_jiffies; unsigned long expires = timer_jiffies + NEXT_TIMER_MAX_DELTA; int index, slot, array, found = 0; struct timer_list *nte; - tvec_t *varray[4]; + struct tvec *varray[4]; /* Look for timer events in tv1. */ index = slot = timer_jiffies & TVR_MASK; @@ -716,7 +714,7 @@ cascade: varray[3] = &base->tv5; for (array = 0; array < 4; array++) { - tvec_t *varp = varray[array]; + struct tvec *varp = varray[array]; index = slot = timer_jiffies & TVN_MASK; do { @@ -795,7 +793,7 @@ static unsigned long cmp_next_hrtimer_event(unsigned long now, */ unsigned long get_next_timer_interrupt(unsigned long now) { - tvec_base_t *base = __get_cpu_var(tvec_bases); + struct tvec_base *base = __get_cpu_var(tvec_bases); unsigned long expires; spin_lock(&base->lock); @@ -820,12 +818,14 @@ unsigned long next_timer_interrupt(void) #ifndef CONFIG_VIRT_CPU_ACCOUNTING void account_process_tick(struct task_struct *p, int user_tick) { + cputime_t one_jiffy = jiffies_to_cputime(1); + if (user_tick) { - account_user_time(p, jiffies_to_cputime(1)); - account_user_time_scaled(p, jiffies_to_cputime(1)); + account_user_time(p, one_jiffy); + account_user_time_scaled(p, cputime_to_scaled(one_jiffy)); } else { - account_system_time(p, HARDIRQ_OFFSET, jiffies_to_cputime(1)); - account_system_time_scaled(p, jiffies_to_cputime(1)); + account_system_time(p, HARDIRQ_OFFSET, one_jiffy); + account_system_time_scaled(p, cputime_to_scaled(one_jiffy)); } } #endif @@ -894,9 +894,9 @@ static inline void calc_load(unsigned long ticks) */ static void run_timer_softirq(struct softirq_action *h) { - tvec_base_t *base = __get_cpu_var(tvec_bases); + struct tvec_base *base = __get_cpu_var(tvec_bases); - hrtimer_run_queues(); + hrtimer_run_pending(); if (time_after_eq(jiffies, base->timer_jiffies)) __run_timers(base); @@ -907,6 +907,7 @@ static void run_timer_softirq(struct softirq_action *h) */ void run_local_timers(void) { + hrtimer_run_queues(); raise_softirq(TIMER_SOFTIRQ); softlockup_tick(); } @@ -978,7 +979,7 @@ asmlinkage long sys_getppid(void) int pid; rcu_read_lock(); - pid = task_ppid_nr_ns(current, current->nsproxy->pid_ns); + pid = task_tgid_nr_ns(current->real_parent, current->nsproxy->pid_ns); rcu_read_unlock(); return pid; @@ -1100,6 +1101,13 @@ signed long __sched schedule_timeout_interruptible(signed long timeout) } EXPORT_SYMBOL(schedule_timeout_interruptible); +signed long __sched schedule_timeout_killable(signed long timeout) +{ + __set_current_state(TASK_KILLABLE); + return schedule_timeout(timeout); +} +EXPORT_SYMBOL(schedule_timeout_killable); + signed long __sched schedule_timeout_uninterruptible(signed long timeout) { __set_current_state(TASK_UNINTERRUPTIBLE); @@ -1219,11 +1227,11 @@ asmlinkage long sys_sysinfo(struct sysinfo __user *info) */ static struct lock_class_key base_lock_keys[NR_CPUS]; -static int __devinit init_timers_cpu(int cpu) +static int __cpuinit init_timers_cpu(int cpu) { int j; - tvec_base_t *base; - static char __devinitdata tvec_base_done[NR_CPUS]; + struct tvec_base *base; + static char __cpuinitdata tvec_base_done[NR_CPUS]; if (!tvec_base_done[cpu]) { static char boot_done; @@ -1277,7 +1285,7 @@ static int __devinit init_timers_cpu(int cpu) } #ifdef CONFIG_HOTPLUG_CPU -static void migrate_timer_list(tvec_base_t *new_base, struct list_head *head) +static void migrate_timer_list(struct tvec_base *new_base, struct list_head *head) { struct timer_list *timer; @@ -1289,10 +1297,10 @@ static void migrate_timer_list(tvec_base_t *new_base, struct list_head *head) } } -static void __devinit migrate_timers(int cpu) +static void __cpuinit migrate_timers(int cpu) { - tvec_base_t *old_base; - tvec_base_t *new_base; + struct tvec_base *old_base; + struct tvec_base *new_base; int i; BUG_ON(cpu_online(cpu)); diff --git a/kernel/user.c b/kernel/user.c index 8320a87f3e5..bc1c48d35cb 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -115,7 +115,7 @@ static void sched_switch_user(struct task_struct *p) { } #if defined(CONFIG_FAIR_USER_SCHED) && defined(CONFIG_SYSFS) -static struct kobject uids_kobject; /* represents /sys/kernel/uids directory */ +static struct kset *uids_kset; /* represents the /sys/kernel/uids/ directory */ static DEFINE_MUTEX(uids_mutex); static inline void uids_mutex_lock(void) @@ -128,86 +128,83 @@ static inline void uids_mutex_unlock(void) mutex_unlock(&uids_mutex); } -/* return cpu shares held by the user */ -static ssize_t cpu_shares_show(struct kset *kset, char *buffer) +/* uid directory attributes */ +static ssize_t cpu_shares_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) { - struct user_struct *up = container_of(kset, struct user_struct, kset); + struct user_struct *up = container_of(kobj, struct user_struct, kobj); - return sprintf(buffer, "%lu\n", sched_group_shares(up->tg)); + return sprintf(buf, "%lu\n", sched_group_shares(up->tg)); } -/* modify cpu shares held by the user */ -static ssize_t cpu_shares_store(struct kset *kset, const char *buffer, - size_t size) +static ssize_t cpu_shares_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t size) { - struct user_struct *up = container_of(kset, struct user_struct, kset); + struct user_struct *up = container_of(kobj, struct user_struct, kobj); unsigned long shares; int rc; - sscanf(buffer, "%lu", &shares); + sscanf(buf, "%lu", &shares); rc = sched_group_set_shares(up->tg, shares); return (rc ? rc : size); } -static void user_attr_init(struct subsys_attribute *sa, char *name, int mode) +static struct kobj_attribute cpu_share_attr = + __ATTR(cpu_share, 0644, cpu_shares_show, cpu_shares_store); + +/* default attributes per uid directory */ +static struct attribute *uids_attributes[] = { + &cpu_share_attr.attr, + NULL +}; + +/* the lifetime of user_struct is not managed by the core (now) */ +static void uids_release(struct kobject *kobj) { - sa->attr.name = name; - sa->attr.mode = mode; - sa->show = cpu_shares_show; - sa->store = cpu_shares_store; + return; } -/* Create "/sys/kernel/uids/<uid>" directory and - * "/sys/kernel/uids/<uid>/cpu_share" file for this user. - */ -static int user_kobject_create(struct user_struct *up) +static struct kobj_type uids_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .default_attrs = uids_attributes, + .release = uids_release, +}; + +/* create /sys/kernel/uids/<uid>/cpu_share file for this user */ +static int uids_user_create(struct user_struct *up) { - struct kset *kset = &up->kset; - struct kobject *kobj = &kset->kobj; + struct kobject *kobj = &up->kobj; int error; - memset(kset, 0, sizeof(struct kset)); - kobj->parent = &uids_kobject; /* create under /sys/kernel/uids dir */ - kobject_set_name(kobj, "%d", up->uid); - kset_init(kset); - user_attr_init(&up->user_attr, "cpu_share", 0644); - - error = kobject_add(kobj); - if (error) + memset(kobj, 0, sizeof(struct kobject)); + kobj->kset = uids_kset; + error = kobject_init_and_add(kobj, &uids_ktype, NULL, "%d", up->uid); + if (error) { + kobject_put(kobj); goto done; - - error = sysfs_create_file(kobj, &up->user_attr.attr); - if (error) - kobject_del(kobj); + } kobject_uevent(kobj, KOBJ_ADD); - done: return error; } -/* create these in sysfs filesystem: +/* create these entries in sysfs: * "/sys/kernel/uids" directory * "/sys/kernel/uids/0" directory (for root user) * "/sys/kernel/uids/0/cpu_share" file (for root user) */ -int __init uids_kobject_init(void) +int __init uids_sysfs_init(void) { - int error; - - /* create under /sys/kernel dir */ - uids_kobject.parent = &kernel_subsys.kobj; - uids_kobject.kset = &kernel_subsys; - kobject_set_name(&uids_kobject, "uids"); - kobject_init(&uids_kobject); + uids_kset = kset_create_and_add("uids", NULL, kernel_kobj); + if (!uids_kset) + return -ENOMEM; - error = kobject_add(&uids_kobject); - if (!error) - error = user_kobject_create(&root_user); - - return error; + return uids_user_create(&root_user); } /* work function to remove sysfs directory for a user and free up @@ -216,7 +213,6 @@ int __init uids_kobject_init(void) static void remove_user_sysfs_dir(struct work_struct *w) { struct user_struct *up = container_of(w, struct user_struct, work); - struct kobject *kobj = &up->kset.kobj; unsigned long flags; int remove_user = 0; @@ -238,9 +234,9 @@ static void remove_user_sysfs_dir(struct work_struct *w) if (!remove_user) goto done; - sysfs_remove_file(kobj, &up->user_attr.attr); - kobject_uevent(kobj, KOBJ_REMOVE); - kobject_del(kobj); + kobject_uevent(&up->kobj, KOBJ_REMOVE); + kobject_del(&up->kobj); + kobject_put(&up->kobj); sched_destroy_user(up); key_put(up->uid_keyring); @@ -267,7 +263,8 @@ static inline void free_user(struct user_struct *up, unsigned long flags) #else /* CONFIG_FAIR_USER_SCHED && CONFIG_SYSFS */ -static inline int user_kobject_create(struct user_struct *up) { return 0; } +int uids_sysfs_init(void) { return 0; } +static inline int uids_user_create(struct user_struct *up) { return 0; } static inline void uids_mutex_lock(void) { } static inline void uids_mutex_unlock(void) { } @@ -322,9 +319,9 @@ void free_uid(struct user_struct *up) struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) { struct hlist_head *hashent = uidhashentry(ns, uid); - struct user_struct *up; + struct user_struct *up, *new; - /* Make uid_hash_find() + user_kobject_create() + uid_hash_insert() + /* Make uid_hash_find() + uids_user_create() + uid_hash_insert() * atomic. */ uids_mutex_lock(); @@ -334,13 +331,9 @@ struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) spin_unlock_irq(&uidhash_lock); if (!up) { - struct user_struct *new; - new = kmem_cache_alloc(uid_cachep, GFP_KERNEL); - if (!new) { - uids_mutex_unlock(); - return NULL; - } + if (!new) + goto out_unlock; new->uid = uid; atomic_set(&new->__count, 1); @@ -356,28 +349,14 @@ struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) #endif new->locked_shm = 0; - if (alloc_uid_keyring(new, current) < 0) { - kmem_cache_free(uid_cachep, new); - uids_mutex_unlock(); - return NULL; - } + if (alloc_uid_keyring(new, current) < 0) + goto out_free_user; - if (sched_create_user(new) < 0) { - key_put(new->uid_keyring); - key_put(new->session_keyring); - kmem_cache_free(uid_cachep, new); - uids_mutex_unlock(); - return NULL; - } + if (sched_create_user(new) < 0) + goto out_put_keys; - if (user_kobject_create(new)) { - sched_destroy_user(new); - key_put(new->uid_keyring); - key_put(new->session_keyring); - kmem_cache_free(uid_cachep, new); - uids_mutex_unlock(); - return NULL; - } + if (uids_user_create(new)) + goto out_destoy_sched; /* * Before adding this, check whether we raced @@ -405,6 +384,17 @@ struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) uids_mutex_unlock(); return up; + +out_destoy_sched: + sched_destroy_user(new); +out_put_keys: + key_put(new->uid_keyring); + key_put(new->session_keyring); +out_free_user: + kmem_cache_free(uid_cachep, new); +out_unlock: + uids_mutex_unlock(); + return NULL; } void switch_uid(struct user_struct *new_user) diff --git a/kernel/wait.c b/kernel/wait.c index 444ddbfaefc..f9876888a56 100644 --- a/kernel/wait.c +++ b/kernel/wait.c @@ -215,7 +215,7 @@ void fastcall __wake_up_bit(wait_queue_head_t *wq, void *word, int bit) { struct wait_bit_key key = __WAIT_BIT_KEY_INITIALIZER(word, bit); if (waitqueue_active(wq)) - __wake_up(wq, TASK_INTERRUPTIBLE|TASK_UNINTERRUPTIBLE, 1, &key); + __wake_up(wq, TASK_NORMAL, 1, &key); } EXPORT_SYMBOL(__wake_up_bit); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 52d5e7c9a8e..52db48e7f6e 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -67,9 +67,8 @@ struct workqueue_struct { #endif }; -/* All the per-cpu workqueues on the system, for hotplug cpu to add/remove - threads to each one as cpus come/go. */ -static DEFINE_MUTEX(workqueue_mutex); +/* Serializes the accesses to the list of workqueues. */ +static DEFINE_SPINLOCK(workqueue_lock); static LIST_HEAD(workqueues); static int singlethread_cpu __read_mostly; @@ -592,8 +591,6 @@ EXPORT_SYMBOL(schedule_delayed_work_on); * Returns zero on success. * Returns -ve errno on failure. * - * Appears to be racy against CPU hotplug. - * * schedule_on_each_cpu() is very slow. */ int schedule_on_each_cpu(work_func_t func) @@ -605,7 +602,7 @@ int schedule_on_each_cpu(work_func_t func) if (!works) return -ENOMEM; - preempt_disable(); /* CPU hotplug */ + get_online_cpus(); for_each_online_cpu(cpu) { struct work_struct *work = per_cpu_ptr(works, cpu); @@ -613,8 +610,8 @@ int schedule_on_each_cpu(work_func_t func) set_bit(WORK_STRUCT_PENDING, work_data_bits(work)); __queue_work(per_cpu_ptr(keventd_wq->cpu_wq, cpu), work); } - preempt_enable(); flush_workqueue(keventd_wq); + put_online_cpus(); free_percpu(works); return 0; } @@ -722,7 +719,8 @@ static void start_workqueue_thread(struct cpu_workqueue_struct *cwq, int cpu) struct workqueue_struct *__create_workqueue_key(const char *name, int singlethread, int freezeable, - struct lock_class_key *key) + struct lock_class_key *key, + const char *lock_name) { struct workqueue_struct *wq; struct cpu_workqueue_struct *cwq; @@ -739,7 +737,7 @@ struct workqueue_struct *__create_workqueue_key(const char *name, } wq->name = name; - lockdep_init_map(&wq->lockdep_map, name, key, 0); + lockdep_init_map(&wq->lockdep_map, lock_name, key, 0); wq->singlethread = singlethread; wq->freezeable = freezeable; INIT_LIST_HEAD(&wq->list); @@ -749,8 +747,10 @@ struct workqueue_struct *__create_workqueue_key(const char *name, err = create_workqueue_thread(cwq, singlethread_cpu); start_workqueue_thread(cwq, -1); } else { - mutex_lock(&workqueue_mutex); + get_online_cpus(); + spin_lock(&workqueue_lock); list_add(&wq->list, &workqueues); + spin_unlock(&workqueue_lock); for_each_possible_cpu(cpu) { cwq = init_cpu_workqueue(wq, cpu); @@ -759,7 +759,7 @@ struct workqueue_struct *__create_workqueue_key(const char *name, err = create_workqueue_thread(cwq, cpu); start_workqueue_thread(cwq, cpu); } - mutex_unlock(&workqueue_mutex); + put_online_cpus(); } if (err) { @@ -774,7 +774,7 @@ static void cleanup_workqueue_thread(struct cpu_workqueue_struct *cwq, int cpu) { /* * Our caller is either destroy_workqueue() or CPU_DEAD, - * workqueue_mutex protects cwq->thread + * get_online_cpus() protects cwq->thread. */ if (cwq->thread == NULL) return; @@ -809,9 +809,11 @@ void destroy_workqueue(struct workqueue_struct *wq) struct cpu_workqueue_struct *cwq; int cpu; - mutex_lock(&workqueue_mutex); + get_online_cpus(); + spin_lock(&workqueue_lock); list_del(&wq->list); - mutex_unlock(&workqueue_mutex); + spin_unlock(&workqueue_lock); + put_online_cpus(); for_each_cpu_mask(cpu, *cpu_map) { cwq = per_cpu_ptr(wq->cpu_wq, cpu); @@ -834,13 +836,6 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, action &= ~CPU_TASKS_FROZEN; switch (action) { - case CPU_LOCK_ACQUIRE: - mutex_lock(&workqueue_mutex); - return NOTIFY_OK; - - case CPU_LOCK_RELEASE: - mutex_unlock(&workqueue_mutex); - return NOTIFY_OK; case CPU_UP_PREPARE: cpu_set(cpu, cpu_populated_map); @@ -853,7 +848,8 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, case CPU_UP_PREPARE: if (!create_workqueue_thread(cwq, cpu)) break; - printk(KERN_ERR "workqueue for %i failed\n", cpu); + printk(KERN_ERR "workqueue [%s] for %i failed\n", + wq->name, cpu); return NOTIFY_BAD; case CPU_ONLINE: |