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-rw-r--r--kernel/Makefile19
-rw-r--r--kernel/audit.c6
-rw-r--r--kernel/auditfilter.c3
-rw-r--r--kernel/capability.c21
-rw-r--r--kernel/cpu.c24
-rw-r--r--kernel/cpuset.c38
-rw-r--r--kernel/exit.c1
-rw-r--r--kernel/fork.c3
-rw-r--r--kernel/hrtimer.c8
-rw-r--r--kernel/kprobes.c2
-rw-r--r--kernel/kthread.c1
-rw-r--r--kernel/lockdep.c33
-rw-r--r--kernel/marker.c30
-rw-r--r--kernel/pm_qos_params.c7
-rw-r--r--kernel/printk.c9
-rw-r--r--kernel/ptrace.c15
-rw-r--r--kernel/rcuclassic.c16
-rw-r--r--kernel/rcupreempt.c20
-rw-r--r--kernel/sched.c807
-rw-r--r--kernel/sched_clock.c137
-rw-r--r--kernel/sched_cpupri.c174
-rw-r--r--kernel/sched_cpupri.h36
-rw-r--r--kernel/sched_debug.c64
-rw-r--r--kernel/sched_fair.c413
-rw-r--r--kernel/sched_features.h7
-rw-r--r--kernel/sched_rt.c405
-rw-r--r--kernel/sched_stats.h42
-rw-r--r--kernel/semaphore.c1
-rw-r--r--kernel/softlockup.c1
-rw-r--r--kernel/spinlock.c2
-rw-r--r--kernel/sysctl.c19
-rw-r--r--kernel/time/tick-broadcast.c6
-rw-r--r--kernel/time/tick-sched.c2
-rw-r--r--kernel/trace/Kconfig135
-rw-r--r--kernel/trace/Makefile24
-rw-r--r--kernel/trace/ftrace.c1727
-rw-r--r--kernel/trace/trace.c3161
-rw-r--r--kernel/trace/trace.h339
-rw-r--r--kernel/trace/trace_functions.c81
-rw-r--r--kernel/trace/trace_irqsoff.c486
-rw-r--r--kernel/trace/trace_mmiotrace.c295
-rw-r--r--kernel/trace/trace_sched_switch.c286
-rw-r--r--kernel/trace/trace_sched_wakeup.c448
-rw-r--r--kernel/trace/trace_selftest.c563
-rw-r--r--kernel/trace/trace_selftest_dynamic.c7
-rw-r--r--kernel/trace/trace_sysprof.c363
-rw-r--r--kernel/workqueue.c2
47 files changed, 9680 insertions, 609 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index 1c9938addb9..f6328e16dfd 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -3,7 +3,7 @@
#
obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
- exit.o itimer.o time.o softirq.o resource.o \
+ cpu.o exit.o itimer.o time.o softirq.o resource.o \
sysctl.o capability.o ptrace.o timer.o user.o \
signal.o sys.o kmod.o workqueue.o pid.o \
rcupdate.o extable.o params.o posix-timers.o \
@@ -11,6 +11,18 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
notifier.o ksysfs.o pm_qos_params.o sched_clock.o
+CFLAGS_REMOVE_sched.o = -mno-spe
+
+ifdef CONFIG_FTRACE
+# Do not trace debug files and internal ftrace files
+CFLAGS_REMOVE_lockdep.o = -pg
+CFLAGS_REMOVE_lockdep_proc.o = -pg
+CFLAGS_REMOVE_mutex-debug.o = -pg
+CFLAGS_REMOVE_rtmutex-debug.o = -pg
+CFLAGS_REMOVE_cgroup-debug.o = -pg
+CFLAGS_REMOVE_sched_clock.o = -pg
+endif
+
obj-$(CONFIG_SYSCTL_SYSCALL_CHECK) += sysctl_check.o
obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-y += time/
@@ -27,7 +39,7 @@ obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
obj-$(CONFIG_DEBUG_RT_MUTEXES) += rtmutex-debug.o
obj-$(CONFIG_RT_MUTEX_TESTER) += rtmutex-tester.o
obj-$(CONFIG_GENERIC_ISA_DMA) += dma.o
-obj-$(CONFIG_SMP) += cpu.o spinlock.o
+obj-$(CONFIG_SMP) += spinlock.o
obj-$(CONFIG_DEBUG_SPINLOCK) += spinlock.o
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
obj-$(CONFIG_UID16) += uid16.o
@@ -69,6 +81,9 @@ obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
obj-$(CONFIG_MARKERS) += marker.o
obj-$(CONFIG_LATENCYTOP) += latencytop.o
+obj-$(CONFIG_FTRACE) += trace/
+obj-$(CONFIG_TRACING) += trace/
+obj-$(CONFIG_SMP) += sched_cpupri.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/audit.c b/kernel/audit.c
index e8692a5748c..e092f1c0ce3 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -738,7 +738,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
if (!audit_enabled && msg_type != AUDIT_USER_AVC)
return 0;
- err = audit_filter_user(&NETLINK_CB(skb), msg_type);
+ err = audit_filter_user(&NETLINK_CB(skb));
if (err == 1) {
err = 0;
if (msg_type == AUDIT_USER_TTY) {
@@ -779,7 +779,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
}
/* fallthrough */
case AUDIT_LIST:
- err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
+ err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
uid, seq, data, nlmsg_len(nlh),
loginuid, sessionid, sid);
break;
@@ -798,7 +798,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
}
/* fallthrough */
case AUDIT_LIST_RULES:
- err = audit_receive_filter(nlh->nlmsg_type, NETLINK_CB(skb).pid,
+ err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
uid, seq, data, nlmsg_len(nlh),
loginuid, sessionid, sid);
break;
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 0e0bd27e651..98c50cc671b 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1544,6 +1544,7 @@ static void audit_log_rule_change(uid_t loginuid, u32 sessionid, u32 sid,
* @data: payload data
* @datasz: size of payload data
* @loginuid: loginuid of sender
+ * @sessionid: sessionid for netlink audit message
* @sid: SE Linux Security ID of sender
*/
int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
@@ -1720,7 +1721,7 @@ static int audit_filter_user_rules(struct netlink_skb_parms *cb,
return 1;
}
-int audit_filter_user(struct netlink_skb_parms *cb, int type)
+int audit_filter_user(struct netlink_skb_parms *cb)
{
enum audit_state state = AUDIT_DISABLED;
struct audit_entry *e;
diff --git a/kernel/capability.c b/kernel/capability.c
index cfbe4429948..901e0fdc3ff 100644
--- a/kernel/capability.c
+++ b/kernel/capability.c
@@ -121,6 +121,27 @@ static int cap_validate_magic(cap_user_header_t header, unsigned *tocopy)
* uninteresting and/or not to be changed.
*/
+/*
+ * Atomically modify the effective capabilities returning the original
+ * value. No permission check is performed here - it is assumed that the
+ * caller is permitted to set the desired effective capabilities.
+ */
+kernel_cap_t cap_set_effective(const kernel_cap_t pE_new)
+{
+ kernel_cap_t pE_old;
+
+ spin_lock(&task_capability_lock);
+
+ pE_old = current->cap_effective;
+ current->cap_effective = pE_new;
+
+ spin_unlock(&task_capability_lock);
+
+ return pE_old;
+}
+
+EXPORT_SYMBOL(cap_set_effective);
+
/**
* sys_capget - get the capabilities of a given process.
* @header: pointer to struct that contains capability version and
diff --git a/kernel/cpu.c b/kernel/cpu.c
index c77bc3a1c72..b11f06dc149 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -15,6 +15,28 @@
#include <linux/stop_machine.h>
#include <linux/mutex.h>
+/*
+ * Represents all cpu's present in the system
+ * In systems capable of hotplug, this map could dynamically grow
+ * as new cpu's are detected in the system via any platform specific
+ * method, such as ACPI for e.g.
+ */
+cpumask_t cpu_present_map __read_mostly;
+EXPORT_SYMBOL(cpu_present_map);
+
+#ifndef CONFIG_SMP
+
+/*
+ * Represents all cpu's that are currently online.
+ */
+cpumask_t cpu_online_map __read_mostly = CPU_MASK_ALL;
+EXPORT_SYMBOL(cpu_online_map);
+
+cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;
+EXPORT_SYMBOL(cpu_possible_map);
+
+#else /* CONFIG_SMP */
+
/* Serializes the updates to cpu_online_map, cpu_present_map */
static DEFINE_MUTEX(cpu_add_remove_lock);
@@ -403,3 +425,5 @@ out:
cpu_maps_update_done();
}
#endif /* CONFIG_PM_SLEEP_SMP */
+
+#endif /* CONFIG_SMP */
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 9fceb97e989..459d601947a 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1194,6 +1194,15 @@ static int cpuset_can_attach(struct cgroup_subsys *ss,
if (cpus_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))
return -ENOSPC;
+ if (tsk->flags & PF_THREAD_BOUND) {
+ cpumask_t mask;
+
+ mutex_lock(&callback_mutex);
+ mask = cs->cpus_allowed;
+ mutex_unlock(&callback_mutex);
+ if (!cpus_equal(tsk->cpus_allowed, mask))
+ return -EINVAL;
+ }
return security_task_setscheduler(tsk, 0, NULL);
}
@@ -1207,11 +1216,14 @@ static void cpuset_attach(struct cgroup_subsys *ss,
struct mm_struct *mm;
struct cpuset *cs = cgroup_cs(cont);
struct cpuset *oldcs = cgroup_cs(oldcont);
+ int err;
mutex_lock(&callback_mutex);
guarantee_online_cpus(cs, &cpus);
- set_cpus_allowed_ptr(tsk, &cpus);
+ err = set_cpus_allowed_ptr(tsk, &cpus);
mutex_unlock(&callback_mutex);
+ if (err)
+ return;
from = oldcs->mems_allowed;
to = cs->mems_allowed;
@@ -1882,7 +1894,7 @@ static void scan_for_empty_cpusets(const struct cpuset *root)
* in order to minimize text size.
*/
-static void common_cpu_mem_hotplug_unplug(void)
+static void common_cpu_mem_hotplug_unplug(int rebuild_sd)
{
cgroup_lock();
@@ -1894,7 +1906,8 @@ static void common_cpu_mem_hotplug_unplug(void)
* Scheduler destroys domains on hotplug events.
* Rebuild them based on the current settings.
*/
- rebuild_sched_domains();
+ if (rebuild_sd)
+ rebuild_sched_domains();
cgroup_unlock();
}
@@ -1912,11 +1925,22 @@ static void common_cpu_mem_hotplug_unplug(void)
static int cpuset_handle_cpuhp(struct notifier_block *unused_nb,
unsigned long phase, void *unused_cpu)
{
- if (phase == CPU_DYING || phase == CPU_DYING_FROZEN)
+ switch (phase) {
+ case CPU_UP_CANCELED:
+ case CPU_UP_CANCELED_FROZEN:
+ case CPU_DOWN_FAILED:
+ case CPU_DOWN_FAILED_FROZEN:
+ case CPU_ONLINE:
+ case CPU_ONLINE_FROZEN:
+ case CPU_DEAD:
+ case CPU_DEAD_FROZEN:
+ common_cpu_mem_hotplug_unplug(1);
+ break;
+ default:
return NOTIFY_DONE;
+ }
- common_cpu_mem_hotplug_unplug();
- return 0;
+ return NOTIFY_OK;
}
#ifdef CONFIG_MEMORY_HOTPLUG
@@ -1929,7 +1953,7 @@ static int cpuset_handle_cpuhp(struct notifier_block *unused_nb,
void cpuset_track_online_nodes(void)
{
- common_cpu_mem_hotplug_unplug();
+ common_cpu_mem_hotplug_unplug(0);
}
#endif
diff --git a/kernel/exit.c b/kernel/exit.c
index 8f6185e69b6..ceb25878283 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -13,6 +13,7 @@
#include <linux/personality.h>
#include <linux/tty.h>
#include <linux/mnt_namespace.h>
+#include <linux/iocontext.h>
#include <linux/key.h>
#include <linux/security.h>
#include <linux/cpu.h>
diff --git a/kernel/fork.c b/kernel/fork.c
index 19908b26cf8..16fd412c756 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -23,6 +23,7 @@
#include <linux/sem.h>
#include <linux/file.h>
#include <linux/fdtable.h>
+#include <linux/iocontext.h>
#include <linux/key.h>
#include <linux/binfmts.h>
#include <linux/mman.h>
@@ -909,7 +910,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
rt_mutex_init_task(p);
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_LOCKDEP)
DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
#endif
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 421be5fe5cc..ab80515008f 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -1003,10 +1003,18 @@ hrtimer_start(struct hrtimer *timer, ktime_t tim, const enum hrtimer_mode mode)
*/
raise = timer->state == HRTIMER_STATE_PENDING;
+ /*
+ * We use preempt_disable to prevent this task from migrating after
+ * setting up the softirq and raising it. Otherwise, if me migrate
+ * we will raise the softirq on the wrong CPU.
+ */
+ preempt_disable();
+
unlock_hrtimer_base(timer, &flags);
if (raise)
hrtimer_raise_softirq();
+ preempt_enable();
return ret;
}
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index d4998f81e22..1485ca8d0e0 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -79,7 +79,7 @@ static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL;
*
* For such cases, we now have a blacklist
*/
-struct kprobe_blackpoint kprobe_blacklist[] = {
+static struct kprobe_blackpoint kprobe_blacklist[] = {
{"preempt_schedule",},
{NULL} /* Terminator */
};
diff --git a/kernel/kthread.c b/kernel/kthread.c
index bd1b9ea024e..97747cdd37c 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -180,6 +180,7 @@ void kthread_bind(struct task_struct *k, unsigned int cpu)
set_task_cpu(k, cpu);
k->cpus_allowed = cpumask_of_cpu(cpu);
k->rt.nr_cpus_allowed = 1;
+ k->flags |= PF_THREAD_BOUND;
}
EXPORT_SYMBOL(kthread_bind);
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 81a4e4a3f08..65548eff029 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -39,6 +39,7 @@
#include <linux/irqflags.h>
#include <linux/utsname.h>
#include <linux/hash.h>
+#include <linux/ftrace.h>
#include <asm/sections.h>
@@ -81,6 +82,8 @@ static int graph_lock(void)
__raw_spin_unlock(&lockdep_lock);
return 0;
}
+ /* prevent any recursions within lockdep from causing deadlocks */
+ current->lockdep_recursion++;
return 1;
}
@@ -89,6 +92,7 @@ static inline int graph_unlock(void)
if (debug_locks && !__raw_spin_is_locked(&lockdep_lock))
return DEBUG_LOCKS_WARN_ON(1);
+ current->lockdep_recursion--;
__raw_spin_unlock(&lockdep_lock);
return 0;
}
@@ -982,7 +986,7 @@ check_noncircular(struct lock_class *source, unsigned int depth)
return 1;
}
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
/*
* Forwards and backwards subgraph searching, for the purposes of
* proving that two subgraphs can be connected by a new dependency
@@ -1680,7 +1684,7 @@ valid_state(struct task_struct *curr, struct held_lock *this,
static int mark_lock(struct task_struct *curr, struct held_lock *this,
enum lock_usage_bit new_bit);
-#ifdef CONFIG_TRACE_IRQFLAGS
+#if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING)
/*
* print irq inversion bug:
@@ -2013,11 +2017,13 @@ void early_boot_irqs_on(void)
/*
* Hardirqs will be enabled:
*/
-void trace_hardirqs_on(void)
+void trace_hardirqs_on_caller(unsigned long a0)
{
struct task_struct *curr = current;
unsigned long ip;
+ time_hardirqs_on(CALLER_ADDR0, a0);
+
if (unlikely(!debug_locks || current->lockdep_recursion))
return;
@@ -2055,16 +2061,23 @@ void trace_hardirqs_on(void)
curr->hardirq_enable_event = ++curr->irq_events;
debug_atomic_inc(&hardirqs_on_events);
}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+void trace_hardirqs_on(void)
+{
+ trace_hardirqs_on_caller(CALLER_ADDR0);
+}
EXPORT_SYMBOL(trace_hardirqs_on);
/*
* Hardirqs were disabled:
*/
-void trace_hardirqs_off(void)
+void trace_hardirqs_off_caller(unsigned long a0)
{
struct task_struct *curr = current;
+ time_hardirqs_off(CALLER_ADDR0, a0);
+
if (unlikely(!debug_locks || current->lockdep_recursion))
return;
@@ -2082,7 +2095,12 @@ void trace_hardirqs_off(void)
} else
debug_atomic_inc(&redundant_hardirqs_off);
}
+EXPORT_SYMBOL(trace_hardirqs_off_caller);
+void trace_hardirqs_off(void)
+{
+ trace_hardirqs_off_caller(CALLER_ADDR0);
+}
EXPORT_SYMBOL(trace_hardirqs_off);
/*
@@ -2246,7 +2264,7 @@ static inline int separate_irq_context(struct task_struct *curr,
* Mark a lock with a usage bit, and validate the state transition:
*/
static int mark_lock(struct task_struct *curr, struct held_lock *this,
- enum lock_usage_bit new_bit)
+ enum lock_usage_bit new_bit)
{
unsigned int new_mask = 1 << new_bit, ret = 1;
@@ -2686,7 +2704,7 @@ static void check_flags(unsigned long flags)
* and also avoid lockdep recursion:
*/
void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
- int trylock, int read, int check, unsigned long ip)
+ int trylock, int read, int check, unsigned long ip)
{
unsigned long flags;
@@ -2708,7 +2726,8 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
EXPORT_SYMBOL_GPL(lock_acquire);
-void lock_release(struct lockdep_map *lock, int nested, unsigned long ip)
+void lock_release(struct lockdep_map *lock, int nested,
+ unsigned long ip)
{
unsigned long flags;
diff --git a/kernel/marker.c b/kernel/marker.c
index b5a9fe1d50d..1abfb923b76 100644
--- a/kernel/marker.c
+++ b/kernel/marker.c
@@ -55,8 +55,8 @@ static DEFINE_MUTEX(markers_mutex);
struct marker_entry {
struct hlist_node hlist;
char *format;
- void (*call)(const struct marker *mdata, /* Probe wrapper */
- void *call_private, const char *fmt, ...);
+ /* Probe wrapper */
+ void (*call)(const struct marker *mdata, void *call_private, ...);
struct marker_probe_closure single;
struct marker_probe_closure *multi;
int refcount; /* Number of times armed. 0 if disarmed. */
@@ -91,15 +91,13 @@ EXPORT_SYMBOL_GPL(__mark_empty_function);
* marker_probe_cb Callback that prepares the variable argument list for probes.
* @mdata: pointer of type struct marker
* @call_private: caller site private data
- * @fmt: format string
* @...: Variable argument list.
*
* Since we do not use "typical" pointer based RCU in the 1 argument case, we
* need to put a full smp_rmb() in this branch. This is why we do not use
* rcu_dereference() for the pointer read.
*/
-void marker_probe_cb(const struct marker *mdata, void *call_private,
- const char *fmt, ...)
+void marker_probe_cb(const struct marker *mdata, void *call_private, ...)
{
va_list args;
char ptype;
@@ -120,8 +118,9 @@ void marker_probe_cb(const struct marker *mdata, void *call_private,
/* Must read the ptr before private data. They are not data
* dependant, so we put an explicit smp_rmb() here. */
smp_rmb();
- va_start(args, fmt);
- func(mdata->single.probe_private, call_private, fmt, &args);
+ va_start(args, call_private);
+ func(mdata->single.probe_private, call_private, mdata->format,
+ &args);
va_end(args);
} else {
struct marker_probe_closure *multi;
@@ -136,9 +135,9 @@ void marker_probe_cb(const struct marker *mdata, void *call_private,
smp_read_barrier_depends();
multi = mdata->multi;
for (i = 0; multi[i].func; i++) {
- va_start(args, fmt);
- multi[i].func(multi[i].probe_private, call_private, fmt,
- &args);
+ va_start(args, call_private);
+ multi[i].func(multi[i].probe_private, call_private,
+ mdata->format, &args);
va_end(args);
}
}
@@ -150,13 +149,11 @@ EXPORT_SYMBOL_GPL(marker_probe_cb);
* marker_probe_cb Callback that does not prepare the variable argument list.
* @mdata: pointer of type struct marker
* @call_private: caller site private data
- * @fmt: format string
* @...: Variable argument list.
*
* Should be connected to markers "MARK_NOARGS".
*/
-void marker_probe_cb_noarg(const struct marker *mdata,
- void *call_private, const char *fmt, ...)
+void marker_probe_cb_noarg(const struct marker *mdata, void *call_private, ...)
{
va_list args; /* not initialized */
char ptype;
@@ -172,7 +169,8 @@ void marker_probe_cb_noarg(const struct marker *mdata,
/* Must read the ptr before private data. They are not data
* dependant, so we put an explicit smp_rmb() here. */
smp_rmb();
- func(mdata->single.probe_private, call_private, fmt, &args);
+ func(mdata->single.probe_private, call_private, mdata->format,
+ &args);
} else {
struct marker_probe_closure *multi;
int i;
@@ -186,8 +184,8 @@ void marker_probe_cb_noarg(const struct marker *mdata,
smp_read_barrier_depends();
multi = mdata->multi;
for (i = 0; multi[i].func; i++)
- multi[i].func(multi[i].probe_private, call_private, fmt,
- &args);
+ multi[i].func(multi[i].probe_private, call_private,
+ mdata->format, &args);
}
preempt_enable();
}
diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index 0afe32be4c8..8cb75702638 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -29,6 +29,7 @@
#include <linux/pm_qos_params.h>
#include <linux/sched.h>
+#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/time.h>
@@ -358,15 +359,19 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp)
int ret;
long pm_qos_class;
+ lock_kernel();
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)
+ if (ret >= 0) {
+ unlock_kernel();
return 0;
+ }
}
+ unlock_kernel();
return -EPERM;
}
diff --git a/kernel/printk.c b/kernel/printk.c
index 8fb01c32aa3..5d81a11321f 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -75,6 +75,8 @@ EXPORT_SYMBOL(oops_in_progress);
static DECLARE_MUTEX(console_sem);
static DECLARE_MUTEX(secondary_console_sem);
struct console *console_drivers;
+EXPORT_SYMBOL_GPL(console_drivers);
+
/*
* This is used for debugging the mess that is the VT code by
* keeping track if we have the console semaphore held. It's
@@ -121,6 +123,8 @@ struct console_cmdline
static struct console_cmdline console_cmdline[MAX_CMDLINECONSOLES];
static int selected_console = -1;
static int preferred_console = -1;
+int console_set_on_cmdline;
+EXPORT_SYMBOL(console_set_on_cmdline);
/* Flag: console code may call schedule() */
static int console_may_schedule;
@@ -666,7 +670,7 @@ static int acquire_console_semaphore_for_printk(unsigned int cpu)
return retval;
}
-const char printk_recursion_bug_msg [] =
+static const char printk_recursion_bug_msg [] =
KERN_CRIT "BUG: recent printk recursion!\n";
static int printk_recursion_bug;
@@ -890,6 +894,7 @@ static int __init console_setup(char *str)
*s = 0;
__add_preferred_console(buf, idx, options, brl_options);
+ console_set_on_cmdline = 1;
return 1;
}
__setup("console=", console_setup);
@@ -1041,7 +1046,9 @@ void release_console_sem(void)
_log_end = log_end;
con_start = log_end; /* Flush */
spin_unlock(&logbuf_lock);
+ stop_critical_timings(); /* don't trace print latency */
call_console_drivers(_con_start, _log_end);
+ start_critical_timings();
local_irq_restore(flags);
}
console_locked = 0;
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 6c19e94fd0a..e337390fce0 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -121,7 +121,7 @@ int ptrace_check_attach(struct task_struct *child, int kill)
return ret;
}
-int __ptrace_may_attach(struct task_struct *task)
+int __ptrace_may_access(struct task_struct *task, unsigned int mode)
{
/* May we inspect the given task?
* This check is used both for attaching with ptrace
@@ -148,16 +148,16 @@ int __ptrace_may_attach(struct task_struct *task)
if (!dumpable && !capable(CAP_SYS_PTRACE))
return -EPERM;
- return security_ptrace(current, task);
+ return security_ptrace(current, task, mode);
}
-int ptrace_may_attach(struct task_struct *task)
+bool ptrace_may_access(struct task_struct *task, unsigned int mode)
{
int err;
task_lock(task);
- err = __ptrace_may_attach(task);
+ err = __ptrace_may_access(task, mode);
task_unlock(task);
- return !err;
+ return (!err ? true : false);
}
int ptrace_attach(struct task_struct *task)
@@ -195,7 +195,7 @@ repeat:
/* the same process cannot be attached many times */
if (task->ptrace & PT_PTRACED)
goto bad;
- retval = __ptrace_may_attach(task);
+ retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH);
if (retval)
goto bad;
@@ -494,7 +494,8 @@ int ptrace_traceme(void)
*/
task_lock(current);
if (!(current->ptrace & PT_PTRACED)) {
- ret = security_ptrace(current->parent, current);
+ ret = security_ptrace(current->parent, current,
+ PTRACE_MODE_ATTACH);
/*
* Set the ptrace bit in the process ptrace flags.
*/
diff --git a/kernel/rcuclassic.c b/kernel/rcuclassic.c
index f4ffbd0f306..a38895a5b8e 100644
--- a/kernel/rcuclassic.c
+++ b/kernel/rcuclassic.c
@@ -89,8 +89,22 @@ static void force_quiescent_state(struct rcu_data *rdp,
/*
* Don't send IPI to itself. With irqs disabled,
* rdp->cpu is the current cpu.
+ *
+ * cpu_online_map is updated by the _cpu_down()
+ * using stop_machine_run(). Since we're in irqs disabled
+ * section, stop_machine_run() is not exectuting, hence
+ * the cpu_online_map is stable.
+ *
+ * However, a cpu might have been offlined _just_ before
+ * we disabled irqs while entering here.
+ * And rcu subsystem might not yet have handled the CPU_DEAD
+ * notification, leading to the offlined cpu's bit
+ * being set in the rcp->cpumask.
+ *
+ * Hence cpumask = (rcp->cpumask & cpu_online_map) to prevent
+ * sending smp_reschedule() to an offlined CPU.
*/
- cpumask = rcp->cpumask;
+ cpus_and(cpumask, rcp->cpumask, cpu_online_map);
cpu_clear(rdp->cpu, cpumask);
for_each_cpu_mask(cpu, cpumask)
smp_send_reschedule(cpu);
diff --git a/kernel/rcupreempt.c b/kernel/rcupreempt.c
index 5e02b774070..41d275a81df 100644
--- a/kernel/rcupreempt.c
+++ b/kernel/rcupreempt.c
@@ -925,26 +925,22 @@ void rcu_offline_cpu(int cpu)
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 */
+
+void __cpuinit rcu_online_cpu(int cpu)
{
-}
+ unsigned long flags;
-#endif /* #else #ifdef CONFIG_HOTPLUG_CPU */
+ spin_lock_irqsave(&rcu_ctrlblk.fliplock, flags);
+ cpu_set(cpu, rcu_cpu_online_map);
+ spin_unlock_irqrestore(&rcu_ctrlblk.fliplock, flags);
+}
static void rcu_process_callbacks(struct softirq_action *unused)
{
diff --git a/kernel/sched.c b/kernel/sched.c
index 7c0e7063c11..2317a217810 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -70,10 +70,13 @@
#include <linux/bootmem.h>
#include <linux/debugfs.h>
#include <linux/ctype.h>
+#include <linux/ftrace.h>
#include <asm/tlb.h>
#include <asm/irq_regs.h>
+#include "sched_cpupri.h"
+
/*
* Convert user-nice values [ -20 ... 0 ... 19 ]
* to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
@@ -289,15 +292,15 @@ struct task_group root_task_group;
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;
-#endif
+#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
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;
-#endif
-#else
+#endif /* CONFIG_RT_GROUP_SCHED */
+#else /* !CONFIG_FAIR_GROUP_SCHED */
#define root_task_group init_task_group
-#endif
+#endif /* CONFIG_FAIR_GROUP_SCHED */
/* task_group_lock serializes add/remove of task groups and also changes to
* a task group's cpu shares.
@@ -307,9 +310,9 @@ static DEFINE_SPINLOCK(task_group_lock);
#ifdef CONFIG_FAIR_GROUP_SCHED
#ifdef CONFIG_USER_SCHED
# define INIT_TASK_GROUP_LOAD (2*NICE_0_LOAD)
-#else
+#else /* !CONFIG_USER_SCHED */
# define INIT_TASK_GROUP_LOAD NICE_0_LOAD
-#endif
+#endif /* CONFIG_USER_SCHED */
/*
* A weight of 0 or 1 can cause arithmetics problems.
@@ -363,6 +366,10 @@ static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
#else
static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
+static inline struct task_group *task_group(struct task_struct *p)
+{
+ return NULL;
+}
#endif /* CONFIG_GROUP_SCHED */
@@ -373,6 +380,7 @@ struct cfs_rq {
u64 exec_clock;
u64 min_vruntime;
+ u64 pair_start;
struct rb_root tasks_timeline;
struct rb_node *rb_leftmost;
@@ -401,6 +409,31 @@ struct cfs_rq {
*/
struct list_head leaf_cfs_rq_list;
struct task_group *tg; /* group that "owns" this runqueue */
+
+#ifdef CONFIG_SMP
+ /*
+ * the part of load.weight contributed by tasks
+ */
+ unsigned long task_weight;
+
+ /*
+ * h_load = weight * f(tg)
+ *
+ * Where f(tg) is the recursive weight fraction assigned to
+ * this group.
+ */
+ unsigned long h_load;
+
+ /*
+ * this cpu's part of tg->shares
+ */
+ unsigned long shares;
+
+ /*
+ * load.weight at the time we set shares
+ */
+ unsigned long rq_weight;
+#endif
#endif
};
@@ -452,6 +485,9 @@ struct root_domain {
*/
cpumask_t rto_mask;
atomic_t rto_count;
+#ifdef CONFIG_SMP
+ struct cpupri cpupri;
+#endif
};
/*
@@ -526,6 +562,9 @@ struct rq {
int push_cpu;
/* cpu of this runqueue: */
int cpu;
+ int online;
+
+ unsigned long avg_load_per_task;
struct task_struct *migration_thread;
struct list_head migration_queue;
@@ -607,6 +646,24 @@ static inline void update_rq_clock(struct rq *rq)
# define const_debug static const
#endif
+/**
+ * runqueue_is_locked
+ *
+ * Returns true if the current cpu runqueue is locked.
+ * This interface allows printk to be called with the runqueue lock
+ * held and know whether or not it is OK to wake up the klogd.
+ */
+int runqueue_is_locked(void)
+{
+ int cpu = get_cpu();
+ struct rq *rq = cpu_rq(cpu);
+ int ret;
+
+ ret = spin_is_locked(&rq->lock);
+ put_cpu();
+ return ret;
+}
+
/*
* Debugging: various feature bits
*/
@@ -749,6 +806,12 @@ late_initcall(sched_init_debug);
const_debug unsigned int sysctl_sched_nr_migrate = 32;
/*
+ * ratelimit for updating the group shares.
+ * default: 0.5ms
+ */
+const_debug unsigned int sysctl_sched_shares_ratelimit = 500000;
+
+/*
* period over which we measure -rt task cpu usage in us.
* default: 1s
*/
@@ -775,82 +838,6 @@ static inline u64 global_rt_runtime(void)
return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
}
-unsigned long long time_sync_thresh = 100000;
-
-static DEFINE_PER_CPU(unsigned long long, time_offset);
-static DEFINE_PER_CPU(unsigned long long, prev_cpu_time);
-
-/*
- * Global lock which we take every now and then to synchronize
- * the CPUs time. This method is not warp-safe, but it's good
- * enough to synchronize slowly diverging time sources and thus
- * it's good enough for tracing:
- */
-static DEFINE_SPINLOCK(time_sync_lock);
-static unsigned long long prev_global_time;
-
-static unsigned long long __sync_cpu_clock(unsigned long long time, int cpu)
-{
- /*
- * We want this inlined, to not get tracer function calls
- * in this critical section:
- */
- spin_acquire(&time_sync_lock.dep_map, 0, 0, _THIS_IP_);
- __raw_spin_lock(&time_sync_lock.raw_lock);
-
- if (time < prev_global_time) {
- per_cpu(time_offset, cpu) += prev_global_time - time;
- time = prev_global_time;
- } else {
- prev_global_time = time;
- }
-
- __raw_spin_unlock(&time_sync_lock.raw_lock);
- spin_release(&time_sync_lock.dep_map, 1, _THIS_IP_);
-
- return time;
-}
-
-static unsigned long long __cpu_clock(int cpu)
-{
- unsigned long long now;
-
- /*
- * Only call sched_clock() if the scheduler has already been
- * initialized (some code might call cpu_clock() very early):
- */
- if (unlikely(!scheduler_running))
- return 0;
-
- now = sched_clock_cpu(cpu);
-
- return now;
-}
-
-/*
- * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
- * clock constructed from sched_clock():
- */
-unsigned long long cpu_clock(int cpu)
-{
- unsigned long long prev_cpu_time, time, delta_time;
- unsigned long flags;
-
- local_irq_save(flags);
- prev_cpu_time = per_cpu(prev_cpu_time, cpu);
- time = __cpu_clock(cpu) + per_cpu(time_offset, cpu);
- delta_time = time-prev_cpu_time;
-
- if (unlikely(delta_time > time_sync_thresh)) {
- time = __sync_cpu_clock(time, cpu);
- per_cpu(prev_cpu_time, cpu) = time;
- }
- local_irq_restore(flags);
-
- return time;
-}
-EXPORT_SYMBOL_GPL(cpu_clock);
-
#ifndef prepare_arch_switch
# define prepare_arch_switch(next) do { } while (0)
#endif
@@ -1313,15 +1300,15 @@ void wake_up_idle_cpu(int cpu)
if (!tsk_is_polling(rq->idle))
smp_send_reschedule(cpu);
}
-#endif
+#endif /* CONFIG_NO_HZ */
-#else
+#else /* !CONFIG_SMP */
static void __resched_task(struct task_struct *p, int tif_bit)
{
assert_spin_locked(&task_rq(p)->lock);
set_tsk_thread_flag(p, tif_bit);
}
-#endif
+#endif /* CONFIG_SMP */
#if BITS_PER_LONG == 32
# define WMULT_CONST (~0UL)
@@ -1336,6 +1323,9 @@ static void __resched_task(struct task_struct *p, int tif_bit)
*/
#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
+/*
+ * delta *= weight / lw
+ */
static unsigned long
calc_delta_mine(unsigned long delta_exec, unsigned long weight,
struct load_weight *lw)
@@ -1363,12 +1353,6 @@ calc_delta_mine(unsigned long delta_exec, unsigned long weight,
return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
}
-static inline unsigned long
-calc_delta_fair(unsigned long delta_exec, struct load_weight *lw)
-{
- return calc_delta_mine(delta_exec, NICE_0_LOAD, lw);
-}
-
static inline void update_load_add(struct load_weight *lw, unsigned long inc)
{
lw->weight += inc;
@@ -1479,17 +1463,211 @@ static inline void dec_cpu_load(struct rq *rq, unsigned long 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);
-#else /* CONFIG_SMP */
+
+static unsigned long cpu_avg_load_per_task(int cpu)
+{
+ struct rq *rq = cpu_rq(cpu);
+
+ if (rq->nr_running)
+ rq->avg_load_per_task = rq->load.weight / rq->nr_running;
+
+ return rq->avg_load_per_task;
+}
#ifdef CONFIG_FAIR_GROUP_SCHED
-static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
+
+typedef void (*tg_visitor)(struct task_group *, int, struct sched_domain *);
+
+/*
+ * Iterate the full tree, calling @down when first entering a node and @up when
+ * leaving it for the final time.
+ */
+static void
+walk_tg_tree(tg_visitor down, tg_visitor up, int cpu, struct sched_domain *sd)
+{
+ struct task_group *parent, *child;
+
+ rcu_read_lock();
+ parent = &root_task_group;
+down:
+ (*down)(parent, cpu, sd);
+ list_for_each_entry_rcu(child, &parent->children, siblings) {
+ parent = child;
+ goto down;
+
+up:
+ continue;
+ }
+ (*up)(parent, cpu, sd);
+
+ child = parent;
+ parent = parent->parent;
+ if (parent)
+ goto up;
+ rcu_read_unlock();
+}
+
+static void __set_se_shares(struct sched_entity *se, unsigned long shares);
+
+/*
+ * Calculate and set the cpu's group shares.
+ */
+static void
+__update_group_shares_cpu(struct task_group *tg, int cpu,
+ unsigned long sd_shares, unsigned long sd_rq_weight)
+{
+ int boost = 0;
+ unsigned long shares;
+ unsigned long rq_weight;
+
+ if (!tg->se[cpu])
+ return;
+
+ rq_weight = tg->cfs_rq[cpu]->load.weight;
+
+ /*
+ * If there are currently no tasks on the cpu pretend there is one of
+ * average load so that when a new task gets to run here it will not
+ * get delayed by group starvation.
+ */
+ if (!rq_weight) {
+ boost = 1;
+ rq_weight = NICE_0_LOAD;
+ }
+
+ if (unlikely(rq_weight > sd_rq_weight))
+ rq_weight = sd_rq_weight;
+
+ /*
+ * \Sum shares * rq_weight
+ * shares = -----------------------
+ * \Sum rq_weight
+ *
+ */
+ shares = (sd_shares * rq_weight) / (sd_rq_weight + 1);
+
+ /*
+ * record the actual number of shares, not the boosted amount.
+ */
+ tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
+ tg->cfs_rq[cpu]->rq_weight = rq_weight;
+
+ if (shares < MIN_SHARES)
+ shares = MIN_SHARES;
+ else if (shares > MAX_SHARES)
+ shares = MAX_SHARES;
+
+ __set_se_shares(tg->se[cpu], shares);
+}
+
+/*
+ * Re-compute the task group their per cpu shares over the given domain.
+ * This needs to be done in a bottom-up fashion because the rq weight of a
+ * parent group depends on the shares of its child groups.
+ */
+static void
+tg_shares_up(struct task_group *tg, int cpu, struct sched_domain *sd)
+{
+ unsigned long rq_weight = 0;
+ unsigned long shares = 0;
+ int i;
+
+ for_each_cpu_mask(i, sd->span) {
+ rq_weight += tg->cfs_rq[i]->load.weight;
+ shares += tg->cfs_rq[i]->shares;
+ }
+
+ if ((!shares && rq_weight) || shares > tg->shares)
+ shares = tg->shares;
+
+ if (!sd->parent || !(sd->parent->flags & SD_LOAD_BALANCE))
+ shares = tg->shares;
+
+ if (!rq_weight)
+ rq_weight = cpus_weight(sd->span) * NICE_0_LOAD;
+
+ for_each_cpu_mask(i, sd->span) {
+ struct rq *rq = cpu_rq(i);
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ __update_group_shares_cpu(tg, i, shares, rq_weight);
+ spin_unlock_irqrestore(&rq->lock, flags);
+ }
+}
+
+/*
+ * Compute the cpu's hierarchical load factor for each task group.
+ * This needs to be done in a top-down fashion because the load of a child
+ * group is a fraction of its parents load.
+ */
+static void
+tg_load_down(struct task_group *tg, int cpu, struct sched_domain *sd)
+{
+ unsigned long load;
+
+ if (!tg->parent) {
+ load = cpu_rq(cpu)->load.weight;
+ } else {
+ load = tg->parent->cfs_rq[cpu]->h_load;
+ load *= tg->cfs_rq[cpu]->shares;
+ load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
+ }
+
+ tg->cfs_rq[cpu]->h_load = load;
+}
+
+static void
+tg_nop(struct task_group *tg, int cpu, struct sched_domain *sd)
{
}
+
+static void update_shares(struct sched_domain *sd)
+{
+ u64 now = cpu_clock(raw_smp_processor_id());
+ s64 elapsed = now - sd->last_update;
+
+ if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {
+ sd->last_update = now;
+ walk_tg_tree(tg_nop, tg_shares_up, 0, sd);
+ }
+}
+
+static void update_shares_locked(struct rq *rq, struct sched_domain *sd)
+{
+ spin_unlock(&rq->lock);
+ update_shares(sd);
+ spin_lock(&rq->lock);
+}
+
+static void update_h_load(int cpu)
+{
+ walk_tg_tree(tg_load_down, tg_nop, cpu, NULL);
+}
+
+#else
+
+static inline void update_shares(struct sched_domain *sd)
+{
+}
+
+static inline void update_shares_locked(struct rq *rq, struct sched_domain *sd)
+{
+}
+
#endif
-#endif /* CONFIG_SMP */
+#endif
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
+{
+#ifdef CONFIG_SMP
+ cfs_rq->shares = shares;
+#endif
+}
+#endif
#include "sched_stats.h"
#include "sched_idletask.c"
@@ -1500,27 +1678,17 @@ static void cfs_rq_set_shares(struct cfs_rq *cfs_rq, unsigned long shares)
#endif
#define sched_class_highest (&rt_sched_class)
+#define for_each_class(class) \
+ for (class = sched_class_highest; class; class = class->next)
-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)
@@ -1544,6 +1712,12 @@ static void set_load_weight(struct task_struct *p)
p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
}
+static void update_avg(u64 *avg, u64 sample)
+{
+ s64 diff = sample - *avg;
+ *avg += diff >> 3;
+}
+
static void enqueue_task(struct rq *rq, struct task_struct *p, int wakeup)
{
sched_info_queued(p);
@@ -1553,6 +1727,13 @@ static void enqueue_task(struct rq *rq, struct task_struct *p, int wakeup)
static void dequeue_task(struct rq *rq, struct task_struct *p, int sleep)
{
+ if (sleep && p->se.last_wakeup) {
+ update_avg(&p->se.avg_overlap,
+ p->se.sum_exec_runtime - p->se.last_wakeup);
+ p->se.last_wakeup = 0;
+ }
+
+ sched_info_dequeued(p);
p->sched_class->dequeue_task(rq, p, sleep);
p->se.on_rq = 0;
}
@@ -1612,7 +1793,7 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
rq->nr_uninterruptible--;
enqueue_task(rq, p, wakeup);
- inc_nr_running(p, rq);
+ inc_nr_running(rq);
}
/*
@@ -1624,7 +1805,7 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
rq->nr_uninterruptible++;
dequeue_task(rq, p, sleep);
- dec_nr_running(p, rq);
+ dec_nr_running(rq);
}
/**
@@ -1636,12 +1817,6 @@ inline int task_curr(const struct task_struct *p)
return cpu_curr(task_cpu(p)) == p;
}
-/* Used instead of source_load when we know the type == 0 */
-unsigned long weighted_cpuload(const int cpu)
-{
- return cpu_rq(cpu)->load.weight;
-}
-
static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
{
set_task_rq(p, cpu);
@@ -1670,6 +1845,12 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
#ifdef CONFIG_SMP
+/* Used instead of source_load when we know the type == 0 */
+static unsigned long weighted_cpuload(const int cpu)
+{
+ return cpu_rq(cpu)->load.weight;
+}
+
/*
* Is this task likely cache-hot:
*/
@@ -1880,7 +2061,7 @@ static unsigned long source_load(int cpu, int type)
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
- if (type == 0)
+ if (type == 0 || !sched_feat(LB_BIAS))
return total;
return min(rq->cpu_load[type-1], total);
@@ -1895,25 +2076,13 @@ static unsigned long target_load(int cpu, int type)
struct rq *rq = cpu_rq(cpu);
unsigned long total = weighted_cpuload(cpu);
- if (type == 0)
+ if (type == 0 || !sched_feat(LB_BIAS))
return total;
return max(rq->cpu_load[type-1], total);
}
/*
- * Return the average load per task on the cpu's run queue
- */
-static unsigned long cpu_avg_load_per_task(int cpu)
-{
- struct rq *rq = cpu_rq(cpu);
- unsigned long total = weighted_cpuload(cpu);
- unsigned long n = rq->nr_running;
-
- return n ? total / n : SCHED_LOAD_SCALE;
-}
-
-/*
* find_idlest_group finds and returns the least busy CPU group within the
* domain.
*/
@@ -2019,6 +2188,9 @@ static int sched_balance_self(int cpu, int flag)
sd = tmp;
}
+ if (sd)
+ update_shares(sd);
+
while (sd) {
cpumask_t span, tmpmask;
struct sched_group *group;
@@ -2085,6 +2257,22 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
if (!sched_feat(SYNC_WAKEUPS))
sync = 0;
+#ifdef CONFIG_SMP
+ if (sched_feat(LB_WAKEUP_UPDATE)) {
+ struct sched_domain *sd;
+
+ this_cpu = raw_smp_processor_id();
+ cpu = task_cpu(p);
+
+ for_each_domain(this_cpu, sd) {
+ if (cpu_isset(cpu, sd->span)) {
+ update_shares(sd);
+ break;
+ }
+ }
+ }
+#endif
+
smp_wmb();
rq = task_rq_lock(p, &flags);
old_state = p->state;
@@ -2131,7 +2319,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
}
}
}
-#endif
+#endif /* CONFIG_SCHEDSTATS */
out_activate:
#endif /* CONFIG_SMP */
@@ -2149,6 +2337,9 @@ out_activate:
success = 1;
out_running:
+ trace_mark(kernel_sched_wakeup,
+ "pid %d state %ld ## rq %p task %p rq->curr %p",
+ p->pid, p->state, rq, p, rq->curr);
check_preempt_curr(rq, p);
p->state = TASK_RUNNING;
@@ -2157,6 +2348,8 @@ out_running:
p->sched_class->task_wake_up(rq, p);
#endif
out:
+ current->se.last_wakeup = current->se.sum_exec_runtime;
+
task_rq_unlock(rq, &flags);
return success;
@@ -2277,8 +2470,11 @@ void 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);
}
+ trace_mark(kernel_sched_wakeup_new,
+ "pid %d state %ld ## rq %p task %p rq->curr %p",
+ p->pid, p->state, rq, p, rq->curr);
check_preempt_curr(rq, p);
#ifdef CONFIG_SMP
if (p->sched_class->task_wake_up)
@@ -2331,7 +2527,7 @@ fire_sched_out_preempt_notifiers(struct task_struct *curr,
notifier->ops->sched_out(notifier, next);
}
-#else
+#else /* !CONFIG_PREEMPT_NOTIFIERS */
static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
{
@@ -2343,7 +2539,7 @@ fire_sched_out_preempt_notifiers(struct task_struct *curr,
{
}
-#endif
+#endif /* CONFIG_PREEMPT_NOTIFIERS */
/**
* prepare_task_switch - prepare to switch tasks
@@ -2451,6 +2647,11 @@ context_switch(struct rq *rq, struct task_struct *prev,
struct mm_struct *mm, *oldmm;
prepare_task_switch(rq, prev, next);
+ trace_mark(kernel_sched_schedule,
+ "prev_pid %d next_pid %d prev_state %ld "
+ "## rq %p prev %p next %p",
+ prev->pid, next->pid, prev->state,
+ rq, prev, next);
mm = next->mm;
oldmm = prev->active_mm;
/*
@@ -2785,7 +2986,7 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
enum cpu_idle_type idle, int *all_pinned,
int *this_best_prio, struct rq_iterator *iterator)
{
- int loops = 0, pulled = 0, pinned = 0, skip_for_load;
+ int loops = 0, pulled = 0, pinned = 0;
struct task_struct *p;
long rem_load_move = max_load_move;
@@ -2801,14 +3002,8 @@ balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
next:
if (!p || loops++ > sysctl_sched_nr_migrate)
goto out;
- /*
- * To help distribute high priority tasks across CPUs we don't
- * skip a task if it will be the highest priority task (i.e. smallest
- * prio value) on its new queue regardless of its load weight
- */
- skip_for_load = (p->se.load.weight >> 1) > rem_load_move +
- SCHED_LOAD_SCALE_FUZZ;
- if ((skip_for_load && p->prio >= *this_best_prio) ||
+
+ if ((p->se.load.weight >> 1) > rem_load_move ||
!can_migrate_task(p, busiest, this_cpu, sd, idle, &pinned)) {
p = iterator->next(iterator->arg);
goto next;
@@ -2863,6 +3058,10 @@ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
max_load_move - total_load_moved,
sd, idle, all_pinned, &this_best_prio);
class = class->next;
+
+ if (idle == CPU_NEWLY_IDLE && this_rq->nr_running)
+ break;
+
} while (class && max_load_move > total_load_moved);
return total_load_moved > 0;
@@ -2939,6 +3138,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
max_load = this_load = total_load = total_pwr = 0;
busiest_load_per_task = busiest_nr_running = 0;
this_load_per_task = this_nr_running = 0;
+
if (idle == CPU_NOT_IDLE)
load_idx = sd->busy_idx;
else if (idle == CPU_NEWLY_IDLE)
@@ -2953,6 +3153,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
int __group_imb = 0;
unsigned int balance_cpu = -1, first_idle_cpu = 0;
unsigned long sum_nr_running, sum_weighted_load;
+ unsigned long sum_avg_load_per_task;
+ unsigned long avg_load_per_task;
local_group = cpu_isset(this_cpu, group->cpumask);
@@ -2961,6 +3163,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
/* Tally up the load of all CPUs in the group */
sum_weighted_load = sum_nr_running = avg_load = 0;
+ sum_avg_load_per_task = avg_load_per_task = 0;
+
max_cpu_load = 0;
min_cpu_load = ~0UL;
@@ -2994,6 +3198,8 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
avg_load += load;
sum_nr_running += rq->nr_running;
sum_weighted_load += weighted_cpuload(i);
+
+ sum_avg_load_per_task += cpu_avg_load_per_task(i);
}
/*
@@ -3015,7 +3221,20 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
avg_load = sg_div_cpu_power(group,
avg_load * SCHED_LOAD_SCALE);
- if ((max_cpu_load - min_cpu_load) > SCHED_LOAD_SCALE)
+
+ /*
+ * Consider the group unbalanced when the imbalance is larger
+ * than the average weight of two tasks.
+ *
+ * APZ: with cgroup the avg task weight can vary wildly and
+ * might not be a suitable number - should we keep a
+ * normalized nr_running number somewhere that negates
+ * the hierarchy?
+ */
+ avg_load_per_task = sg_div_cpu_power(group,
+ sum_avg_load_per_task * SCHED_LOAD_SCALE);
+
+ if ((max_cpu_load - min_cpu_load) > 2*avg_load_per_task)
__group_imb = 1;
group_capacity = group->__cpu_power / SCHED_LOAD_SCALE;
@@ -3156,9 +3375,9 @@ small_imbalance:
if (busiest_load_per_task > this_load_per_task)
imbn = 1;
} else
- this_load_per_task = SCHED_LOAD_SCALE;
+ this_load_per_task = cpu_avg_load_per_task(this_cpu);
- if (max_load - this_load + SCHED_LOAD_SCALE_FUZZ >=
+ if (max_load - this_load + 2*busiest_load_per_task >=
busiest_load_per_task * imbn) {
*imbalance = busiest_load_per_task;
return busiest;
@@ -3284,6 +3503,7 @@ static int load_balance(int this_cpu, struct rq *this_rq,
schedstat_inc(sd, lb_count[idle]);
redo:
+ update_shares(sd);
group = find_busiest_group(sd, this_cpu, &imbalance, idle, &sd_idle,
cpus, balance);
@@ -3386,8 +3606,9 @@ redo:
if (!ld_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
!test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
- return -1;
- return ld_moved;
+ ld_moved = -1;
+
+ goto out;
out_balanced:
schedstat_inc(sd, lb_balanced[idle]);
@@ -3402,8 +3623,13 @@ out_one_pinned:
if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER &&
!test_sd_parent(sd, SD_POWERSAVINGS_BALANCE))
- return -1;
- return 0;
+ ld_moved = -1;
+ else
+ ld_moved = 0;
+out:
+ if (ld_moved)
+ update_shares(sd);
+ return ld_moved;
}
/*
@@ -3438,6 +3664,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd,
schedstat_inc(sd, lb_count[CPU_NEWLY_IDLE]);
redo:
+ update_shares_locked(this_rq, sd);
group = find_busiest_group(sd, this_cpu, &imbalance, CPU_NEWLY_IDLE,
&sd_idle, cpus, NULL);
if (!group) {
@@ -3481,6 +3708,7 @@ redo:
} else
sd->nr_balance_failed = 0;
+ update_shares_locked(this_rq, sd);
return ld_moved;
out_balanced:
@@ -3672,6 +3900,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
/* Earliest time when we have to do rebalance again */
unsigned long next_balance = jiffies + 60*HZ;
int update_next_balance = 0;
+ int need_serialize;
cpumask_t tmp;
for_each_domain(cpu, sd) {
@@ -3689,8 +3918,9 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
if (interval > HZ*NR_CPUS/10)
interval = HZ*NR_CPUS/10;
+ need_serialize = sd->flags & SD_SERIALIZE;
- if (sd->flags & SD_SERIALIZE) {
+ if (need_serialize) {
if (!spin_trylock(&balancing))
goto out;
}
@@ -3706,7 +3936,7 @@ static void rebalance_domains(int cpu, enum cpu_idle_type idle)
}
sd->last_balance = jiffies;
}
- if (sd->flags & SD_SERIALIZE)
+ if (need_serialize)
spin_unlock(&balancing);
out:
if (time_after(next_balance, sd->last_balance + interval)) {
@@ -4021,26 +4251,44 @@ void scheduler_tick(void)
#endif
}
-#if defined(CONFIG_PREEMPT) && defined(CONFIG_DEBUG_PREEMPT)
+#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
+ defined(CONFIG_PREEMPT_TRACER))
+
+static inline unsigned long get_parent_ip(unsigned long addr)
+{
+ if (in_lock_functions(addr)) {
+ addr = CALLER_ADDR2;
+ if (in_lock_functions(addr))
+ addr = CALLER_ADDR3;
+ }
+ return addr;
+}
void __kprobes add_preempt_count(int val)
{
+#ifdef CONFIG_DEBUG_PREEMPT
/*
* Underflow?
*/
if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0)))
return;
+#endif
preempt_count() += val;
+#ifdef CONFIG_DEBUG_PREEMPT
/*
* Spinlock count overflowing soon?
*/
DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
PREEMPT_MASK - 10);
+#endif
+ if (preempt_count() == val)
+ trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
}
EXPORT_SYMBOL(add_preempt_count);
void __kprobes sub_preempt_count(int val)
{
+#ifdef CONFIG_DEBUG_PREEMPT
/*
* Underflow?
*/
@@ -4052,7 +4300,10 @@ void __kprobes sub_preempt_count(int val)
if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) &&
!(preempt_count() & PREEMPT_MASK)))
return;
+#endif
+ if (preempt_count() == val)
+ trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
preempt_count() -= val;
}
EXPORT_SYMBOL(sub_preempt_count);
@@ -4070,6 +4321,7 @@ static noinline void __schedule_bug(struct task_struct *prev)
prev->comm, prev->pid, preempt_count());
debug_show_held_locks(prev);
+ print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
@@ -4143,7 +4395,7 @@ asmlinkage void __sched schedule(void)
struct task_struct *prev, *next;
unsigned long *switch_count;
struct rq *rq;
- int cpu;
+ int cpu, hrtick = sched_feat(HRTICK);
need_resched:
preempt_disable();
@@ -4158,7 +4410,8 @@ need_resched_nonpreemptible:
schedule_debug(prev);
- hrtick_clear(rq);
+ if (hrtick)
+ hrtick_clear(rq);
/*
* Do the rq-clock update outside the rq lock:
@@ -4204,7 +4457,8 @@ need_resched_nonpreemptible:
} else
spin_unlock_irq(&rq->lock);
- hrtick_set(rq);
+ if (hrtick)
+ hrtick_set(rq);
if (unlikely(reacquire_kernel_lock(current) < 0))
goto need_resched_nonpreemptible;
@@ -4586,10 +4840,8 @@ 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);
@@ -4599,7 +4851,6 @@ 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:
@@ -5094,24 +5345,6 @@ asmlinkage long sys_sched_setaffinity(pid_t pid, unsigned int len,
return sched_setaffinity(pid, &new_mask);
}
-/*
- * Represents all cpu's present in the system
- * In systems capable of hotplug, this map could dynamically grow
- * as new cpu's are detected in the system via any platform specific
- * method, such as ACPI for e.g.
- */
-
-cpumask_t cpu_present_map __read_mostly;
-EXPORT_SYMBOL(cpu_present_map);
-
-#ifndef CONFIG_SMP
-cpumask_t cpu_online_map __read_mostly = CPU_MASK_ALL;
-EXPORT_SYMBOL(cpu_online_map);
-
-cpumask_t cpu_possible_map __read_mostly = CPU_MASK_ALL;
-EXPORT_SYMBOL(cpu_possible_map);
-#endif
-
long sched_getaffinity(pid_t pid, cpumask_t *mask)
{
struct task_struct *p;
@@ -5408,7 +5641,7 @@ out_unlock:
return retval;
}
-static const char stat_nam[] = "RSDTtZX";
+static const char stat_nam[] = TASK_STATE_TO_CHAR_STR;
void sched_show_task(struct task_struct *p)
{
@@ -5595,6 +5828,12 @@ int set_cpus_allowed_ptr(struct task_struct *p, const cpumask_t *new_mask)
goto out;
}
+ if (unlikely((p->flags & PF_THREAD_BOUND) && p != current &&
+ !cpus_equal(p->cpus_allowed, *new_mask))) {
+ ret = -EINVAL;
+ goto out;
+ }
+
if (p->sched_class->set_cpus_allowed)
p->sched_class->set_cpus_allowed(p, new_mask);
else {
@@ -5646,10 +5885,10 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
double_rq_lock(rq_src, rq_dest);
/* Already moved. */
if (task_cpu(p) != src_cpu)
- goto out;
+ goto done;
/* Affinity changed (again). */
if (!cpu_isset(dest_cpu, p->cpus_allowed))
- goto out;
+ goto fail;
on_rq = p->se.on_rq;
if (on_rq)
@@ -5660,8 +5899,9 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
activate_task(rq_dest, p, 0);
check_preempt_curr(rq_dest, p);
}
+done:
ret = 1;
-out:
+fail:
double_rq_unlock(rq_src, rq_dest);
return ret;
}
@@ -5911,6 +6151,7 @@ static void migrate_dead_tasks(unsigned int dead_cpu)
next = pick_next_task(rq, rq->curr);
if (!next)
break;
+ next->sched_class->put_prev_task(rq, next);
migrate_dead(dead_cpu, next);
}
@@ -6082,6 +6323,36 @@ static void unregister_sched_domain_sysctl(void)
}
#endif
+static void set_rq_online(struct rq *rq)
+{
+ if (!rq->online) {
+ const struct sched_class *class;
+
+ cpu_set(rq->cpu, rq->rd->online);
+ rq->online = 1;
+
+ for_each_class(class) {
+ if (class->rq_online)
+ class->rq_online(rq);
+ }
+ }
+}
+
+static void set_rq_offline(struct rq *rq)
+{
+ if (rq->online) {
+ const struct sched_class *class;
+
+ for_each_class(class) {
+ if (class->rq_offline)
+ class->rq_offline(rq);
+ }
+
+ cpu_clear(rq->cpu, rq->rd->online);
+ rq->online = 0;
+ }
+}
+
/*
* migration_call - callback that gets triggered when a CPU is added.
* Here we can start up the necessary migration thread for the new CPU.
@@ -6119,7 +6390,8 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpu_isset(cpu, rq->rd->span));
- cpu_set(cpu, rq->rd->online);
+
+ set_rq_online(rq);
}
spin_unlock_irqrestore(&rq->lock, flags);
break;
@@ -6180,7 +6452,7 @@ migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
spin_lock_irqsave(&rq->lock, flags);
if (rq->rd) {
BUG_ON(!cpu_isset(cpu, rq->rd->span));
- cpu_clear(cpu, rq->rd->online);
+ set_rq_offline(rq);
}
spin_unlock_irqrestore(&rq->lock, flags);
break;
@@ -6214,6 +6486,28 @@ void __init migration_init(void)
#ifdef CONFIG_SCHED_DEBUG
+static inline const char *sd_level_to_string(enum sched_domain_level lvl)
+{
+ switch (lvl) {
+ case SD_LV_NONE:
+ return "NONE";
+ case SD_LV_SIBLING:
+ return "SIBLING";
+ case SD_LV_MC:
+ return "MC";
+ case SD_LV_CPU:
+ return "CPU";
+ case SD_LV_NODE:
+ return "NODE";
+ case SD_LV_ALLNODES:
+ return "ALLNODES";
+ case SD_LV_MAX:
+ return "MAX";
+
+ }
+ return "MAX";
+}
+
static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
cpumask_t *groupmask)
{
@@ -6233,7 +6527,8 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
return -1;
}
- printk(KERN_CONT "span %s\n", str);
+ printk(KERN_CONT "span %s level %s\n",
+ str, sd_level_to_string(sd->level));
if (!cpu_isset(cpu, sd->span)) {
printk(KERN_ERR "ERROR: domain->span does not contain "
@@ -6317,9 +6612,9 @@ static void sched_domain_debug(struct sched_domain *sd, int cpu)
}
kfree(groupmask);
}
-#else
+#else /* !CONFIG_SCHED_DEBUG */
# define sched_domain_debug(sd, cpu) do { } while (0)
-#endif
+#endif /* CONFIG_SCHED_DEBUG */
static int sd_degenerate(struct sched_domain *sd)
{
@@ -6379,20 +6674,16 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
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);
- }
+ if (cpu_isset(rq->cpu, old_rd->online))
+ set_rq_offline(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);
@@ -6403,12 +6694,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *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);
- }
+ set_rq_online(rq);
spin_unlock_irqrestore(&rq->lock, flags);
}
@@ -6419,6 +6705,8 @@ static void init_rootdomain(struct root_domain *rd)
cpus_clear(rd->span);
cpus_clear(rd->online);
+
+ cpupri_init(&rd->cpupri);
}
static void init_defrootdomain(void)
@@ -6561,9 +6849,9 @@ static int find_next_best_node(int node, nodemask_t *used_nodes)
min_val = INT_MAX;
- for (i = 0; i < MAX_NUMNODES; i++) {
+ for (i = 0; i < nr_node_ids; i++) {
/* Start at @node */
- n = (node + i) % MAX_NUMNODES;
+ n = (node + i) % nr_node_ids;
if (!nr_cpus_node(n))
continue;
@@ -6613,7 +6901,7 @@ static void sched_domain_node_span(int node, cpumask_t *span)
cpus_or(*span, *span, *nodemask);
}
}
-#endif
+#endif /* CONFIG_NUMA */
int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
@@ -6632,7 +6920,7 @@ cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
*sg = &per_cpu(sched_group_cpus, cpu);
return cpu;
}
-#endif
+#endif /* CONFIG_SCHED_SMT */
/*
* multi-core sched-domains:
@@ -6640,7 +6928,7 @@ cpu_to_cpu_group(int cpu, const cpumask_t *cpu_map, struct sched_group **sg,
#ifdef CONFIG_SCHED_MC
static DEFINE_PER_CPU(struct sched_domain, core_domains);
static DEFINE_PER_CPU(struct sched_group, sched_group_core);
-#endif
+#endif /* CONFIG_SCHED_MC */
#if defined(CONFIG_SCHED_MC) && defined(CONFIG_SCHED_SMT)
static int
@@ -6742,7 +7030,7 @@ static void init_numa_sched_groups_power(struct sched_group *group_head)
sg = sg->next;
} while (sg != group_head);
}
-#endif
+#endif /* CONFIG_NUMA */
#ifdef CONFIG_NUMA
/* Free memory allocated for various sched_group structures */
@@ -6757,7 +7045,7 @@ static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
if (!sched_group_nodes)
continue;
- for (i = 0; i < MAX_NUMNODES; i++) {
+ for (i = 0; i < nr_node_ids; i++) {
struct sched_group *oldsg, *sg = sched_group_nodes[i];
*nodemask = node_to_cpumask(i);
@@ -6779,11 +7067,11 @@ next_sg:
sched_group_nodes_bycpu[cpu] = NULL;
}
}
-#else
+#else /* !CONFIG_NUMA */
static void free_sched_groups(const cpumask_t *cpu_map, cpumask_t *nodemask)
{
}
-#endif
+#endif /* CONFIG_NUMA */
/*
* Initialize sched groups cpu_power.
@@ -6950,7 +7238,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
/*
* Allocate the per-node list of sched groups
*/
- sched_group_nodes = kcalloc(MAX_NUMNODES, sizeof(struct sched_group *),
+ sched_group_nodes = kcalloc(nr_node_ids, sizeof(struct sched_group *),
GFP_KERNEL);
if (!sched_group_nodes) {
printk(KERN_WARNING "Can not alloc sched group node list\n");
@@ -7089,7 +7377,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
#endif
/* Set up physical groups */
- for (i = 0; i < MAX_NUMNODES; i++) {
+ for (i = 0; i < nr_node_ids; i++) {
SCHED_CPUMASK_VAR(nodemask, allmasks);
SCHED_CPUMASK_VAR(send_covered, allmasks);
@@ -7113,7 +7401,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
send_covered, tmpmask);
}
- for (i = 0; i < MAX_NUMNODES; i++) {
+ for (i = 0; i < nr_node_ids; i++) {
/* Set up node groups */
struct sched_group *sg, *prev;
SCHED_CPUMASK_VAR(nodemask, allmasks);
@@ -7152,9 +7440,9 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
cpus_or(*covered, *covered, *nodemask);
prev = sg;
- for (j = 0; j < MAX_NUMNODES; j++) {
+ for (j = 0; j < nr_node_ids; j++) {
SCHED_CPUMASK_VAR(notcovered, allmasks);
- int n = (i + j) % MAX_NUMNODES;
+ int n = (i + j) % nr_node_ids;
node_to_cpumask_ptr(pnodemask, n);
cpus_complement(*notcovered, *covered);
@@ -7207,7 +7495,7 @@ static int __build_sched_domains(const cpumask_t *cpu_map,
}
#ifdef CONFIG_NUMA
- for (i = 0; i < MAX_NUMNODES; i++)
+ for (i = 0; i < nr_node_ids; i++)
init_numa_sched_groups_power(sched_group_nodes[i]);
if (sd_allnodes) {
@@ -7492,7 +7780,7 @@ int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
#endif
return err;
}
-#endif
+#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
/*
* Force a reinitialization of the sched domains hierarchy. The domains
@@ -7503,21 +7791,28 @@ int sched_create_sysfs_power_savings_entries(struct sysdev_class *cls)
static int update_sched_domains(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
+ int cpu = (int)(long)hcpu;
+
switch (action) {
- case CPU_UP_PREPARE:
- case CPU_UP_PREPARE_FROZEN:
case CPU_DOWN_PREPARE:
case CPU_DOWN_PREPARE_FROZEN:
+ disable_runtime(cpu_rq(cpu));
+ /* fall-through */
+ case CPU_UP_PREPARE:
+ case CPU_UP_PREPARE_FROZEN:
detach_destroy_domains(&cpu_online_map);
free_sched_domains();
return NOTIFY_OK;
- case CPU_UP_CANCELED:
- case CPU_UP_CANCELED_FROZEN:
+
case CPU_DOWN_FAILED:
case CPU_DOWN_FAILED_FROZEN:
case CPU_ONLINE:
case CPU_ONLINE_FROZEN:
+ enable_runtime(cpu_rq(cpu));
+ /* fall-through */
+ case CPU_UP_CANCELED:
+ case CPU_UP_CANCELED_FROZEN:
case CPU_DEAD:
case CPU_DEAD_FROZEN:
/*
@@ -7717,8 +8012,8 @@ void __init sched_init(void)
root_task_group.cfs_rq = (struct cfs_rq **)ptr;
ptr += nr_cpu_ids * sizeof(void **);
-#endif
-#endif
+#endif /* CONFIG_USER_SCHED */
+#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
init_task_group.rt_se = (struct sched_rt_entity **)ptr;
ptr += nr_cpu_ids * sizeof(void **);
@@ -7732,8 +8027,8 @@ void __init sched_init(void)
root_task_group.rt_rq = (struct rt_rq **)ptr;
ptr += nr_cpu_ids * sizeof(void **);
-#endif
-#endif
+#endif /* CONFIG_USER_SCHED */
+#endif /* CONFIG_RT_GROUP_SCHED */
}
#ifdef CONFIG_SMP
@@ -7749,8 +8044,8 @@ void __init sched_init(void)
#ifdef CONFIG_USER_SCHED
init_rt_bandwidth(&root_task_group.rt_bandwidth,
global_rt_period(), RUNTIME_INF);
-#endif
-#endif
+#endif /* CONFIG_USER_SCHED */
+#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_GROUP_SCHED
list_add(&init_task_group.list, &task_groups);
@@ -7760,8 +8055,8 @@ void __init sched_init(void)
INIT_LIST_HEAD(&root_task_group.children);
init_task_group.parent = &root_task_group;
list_add(&init_task_group.siblings, &root_task_group.children);
-#endif
-#endif
+#endif /* CONFIG_USER_SCHED */
+#endif /* CONFIG_GROUP_SCHED */
for_each_possible_cpu(i) {
struct rq *rq;
@@ -7841,6 +8136,7 @@ void __init sched_init(void)
rq->next_balance = jiffies;
rq->push_cpu = 0;
rq->cpu = i;
+ rq->online = 0;
rq->migration_thread = NULL;
INIT_LIST_HEAD(&rq->migration_queue);
rq_attach_root(rq, &def_root_domain);
@@ -8080,7 +8376,7 @@ static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
list_del_rcu(&tg->cfs_rq[cpu]->leaf_cfs_rq_list);
}
-#else
+#else /* !CONFG_FAIR_GROUP_SCHED */
static inline void free_fair_sched_group(struct task_group *tg)
{
}
@@ -8098,7 +8394,7 @@ static inline void register_fair_sched_group(struct task_group *tg, int cpu)
static inline void unregister_fair_sched_group(struct task_group *tg, int cpu)
{
}
-#endif
+#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
static void free_rt_sched_group(struct task_group *tg)
@@ -8169,7 +8465,7 @@ static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
{
list_del_rcu(&tg->rt_rq[cpu]->leaf_rt_rq_list);
}
-#else
+#else /* !CONFIG_RT_GROUP_SCHED */
static inline void free_rt_sched_group(struct task_group *tg)
{
}
@@ -8187,7 +8483,7 @@ static inline void register_rt_sched_group(struct task_group *tg, int cpu)
static inline void unregister_rt_sched_group(struct task_group *tg, int cpu)
{
}
-#endif
+#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_GROUP_SCHED
static void free_sched_group(struct task_group *tg)
@@ -8298,17 +8594,14 @@ void sched_move_task(struct task_struct *tsk)
task_rq_unlock(rq, &flags);
}
-#endif
+#endif /* CONFIG_GROUP_SCHED */
#ifdef CONFIG_FAIR_GROUP_SCHED
-static void set_se_shares(struct sched_entity *se, unsigned long shares)
+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);
-
on_rq = se->on_rq;
if (on_rq)
dequeue_entity(cfs_rq, se, 0);
@@ -8318,8 +8611,17 @@ static void set_se_shares(struct sched_entity *se, unsigned long shares)
if (on_rq)
enqueue_entity(cfs_rq, se, 0);
+}
- spin_unlock_irq(&rq->lock);
+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;
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ __set_se_shares(se, shares);
+ spin_unlock_irqrestore(&rq->lock, flags);
}
static DEFINE_MUTEX(shares_mutex);
@@ -8358,8 +8660,13 @@ int sched_group_set_shares(struct task_group *tg, unsigned long shares)
* w/o tripping rebalance_share or load_balance_fair.
*/
tg->shares = shares;
- for_each_possible_cpu(i)
+ for_each_possible_cpu(i) {
+ /*
+ * force a rebalance
+ */
+ cfs_rq_set_shares(tg->cfs_rq[i], 0);
set_se_shares(tg->se[i], shares);
+ }
/*
* Enable load balance activity on this group, by inserting it back on
@@ -8398,7 +8705,7 @@ static unsigned long to_ratio(u64 period, u64 runtime)
#ifdef CONFIG_CGROUP_SCHED
static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
{
- struct task_group *tgi, *parent = tg ? tg->parent : NULL;
+ struct task_group *tgi, *parent = tg->parent;
unsigned long total = 0;
if (!parent) {
@@ -8422,7 +8729,7 @@ static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
}
rcu_read_unlock();
- return total + to_ratio(period, runtime) <
+ return total + to_ratio(period, runtime) <=
to_ratio(ktime_to_ns(parent->rt_bandwidth.rt_period),
parent->rt_bandwidth.rt_runtime);
}
@@ -8525,6 +8832,9 @@ int sched_group_set_rt_period(struct task_group *tg, long rt_period_us)
rt_period = (u64)rt_period_us * NSEC_PER_USEC;
rt_runtime = tg->rt_bandwidth.rt_runtime;
+ if (rt_period == 0)
+ return -EINVAL;
+
return tg_set_bandwidth(tg, rt_period, rt_runtime);
}
@@ -8539,16 +8849,21 @@ long sched_group_rt_period(struct task_group *tg)
static int sched_rt_global_constraints(void)
{
+ struct task_group *tg = &root_task_group;
+ u64 rt_runtime, rt_period;
int ret = 0;
+ rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
+ rt_runtime = tg->rt_bandwidth.rt_runtime;
+
mutex_lock(&rt_constraints_mutex);
- if (!__rt_schedulable(NULL, 1, 0))
+ if (!__rt_schedulable(tg, rt_period, rt_runtime))
ret = -EINVAL;
mutex_unlock(&rt_constraints_mutex);
return ret;
}
-#else
+#else /* !CONFIG_RT_GROUP_SCHED */
static int sched_rt_global_constraints(void)
{
unsigned long flags;
@@ -8566,7 +8881,7 @@ static int sched_rt_global_constraints(void)
return 0;
}
-#endif
+#endif /* CONFIG_RT_GROUP_SCHED */
int sched_rt_handler(struct ctl_table *table, int write,
struct file *filp, void __user *buffer, size_t *lenp,
@@ -8674,7 +8989,7 @@ static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
return (u64) tg->shares;
}
-#endif
+#endif /* CONFIG_FAIR_GROUP_SCHED */
#ifdef CONFIG_RT_GROUP_SCHED
static int cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
@@ -8698,7 +9013,7 @@ static u64 cpu_rt_period_read_uint(struct cgroup *cgrp, struct cftype *cft)
{
return sched_group_rt_period(cgroup_tg(cgrp));
}
-#endif
+#endif /* CONFIG_RT_GROUP_SCHED */
static struct cftype cpu_files[] = {
#ifdef CONFIG_FAIR_GROUP_SCHED
diff --git a/kernel/sched_clock.c b/kernel/sched_clock.c
index ce05271219a..22ed55d1167 100644
--- a/kernel/sched_clock.c
+++ b/kernel/sched_clock.c
@@ -3,6 +3,9 @@
*
* Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
*
+ * Updates and enhancements:
+ * Copyright (C) 2008 Red Hat, Inc. Steven Rostedt <srostedt@redhat.com>
+ *
* Based on code by:
* Ingo Molnar <mingo@redhat.com>
* Guillaume Chazarain <guichaz@gmail.com>
@@ -32,6 +35,11 @@
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+#define MULTI_SHIFT 15
+/* Max is double, Min is 1/2 */
+#define MAX_MULTI (2LL << MULTI_SHIFT)
+#define MIN_MULTI (1LL << (MULTI_SHIFT-1))
+
struct sched_clock_data {
/*
* Raw spinlock - this is a special case: this might be called
@@ -40,11 +48,15 @@ struct sched_clock_data {
*/
raw_spinlock_t lock;
- unsigned long prev_jiffies;
+ unsigned long tick_jiffies;
u64 prev_raw;
u64 tick_raw;
u64 tick_gtod;
u64 clock;
+ s64 multi;
+#ifdef CONFIG_NO_HZ
+ int check_max;
+#endif
};
static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_data);
@@ -71,41 +83,91 @@ void sched_clock_init(void)
struct sched_clock_data *scd = cpu_sdc(cpu);
scd->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
- scd->prev_jiffies = now_jiffies;
+ scd->tick_jiffies = now_jiffies;
scd->prev_raw = 0;
scd->tick_raw = 0;
scd->tick_gtod = ktime_now;
scd->clock = ktime_now;
+ scd->multi = 1 << MULTI_SHIFT;
+#ifdef CONFIG_NO_HZ
+ scd->check_max = 1;
+#endif
}
sched_clock_running = 1;
}
+#ifdef CONFIG_NO_HZ
+/*
+ * The dynamic ticks makes the delta jiffies inaccurate. This
+ * prevents us from checking the maximum time update.
+ * Disable the maximum check during stopped ticks.
+ */
+void sched_clock_tick_stop(int cpu)
+{
+ struct sched_clock_data *scd = cpu_sdc(cpu);
+
+ scd->check_max = 0;
+}
+
+void sched_clock_tick_start(int cpu)
+{
+ struct sched_clock_data *scd = cpu_sdc(cpu);
+
+ scd->check_max = 1;
+}
+
+static int check_max(struct sched_clock_data *scd)
+{
+ return scd->check_max;
+}
+#else
+static int check_max(struct sched_clock_data *scd)
+{
+ return 1;
+}
+#endif /* CONFIG_NO_HZ */
+
/*
* update the percpu scd from the raw @now value
*
* - filter out backward motion
* - use jiffies to generate a min,max window to clip the raw values
*/
-static void __update_sched_clock(struct sched_clock_data *scd, u64 now)
+static void __update_sched_clock(struct sched_clock_data *scd, u64 now, u64 *time)
{
unsigned long now_jiffies = jiffies;
- long delta_jiffies = now_jiffies - scd->prev_jiffies;
+ long delta_jiffies = now_jiffies - scd->tick_jiffies;
u64 clock = scd->clock;
u64 min_clock, max_clock;
s64 delta = now - scd->prev_raw;
WARN_ON_ONCE(!irqs_disabled());
- min_clock = scd->tick_gtod + delta_jiffies * TICK_NSEC;
+
+ /*
+ * At schedule tick the clock can be just under the gtod. We don't
+ * want to push it too prematurely.
+ */
+ min_clock = scd->tick_gtod + (delta_jiffies * TICK_NSEC);
+ if (min_clock > TICK_NSEC)
+ min_clock -= TICK_NSEC / 2;
if (unlikely(delta < 0)) {
clock++;
goto out;
}
- max_clock = min_clock + TICK_NSEC;
+ /*
+ * The clock must stay within a jiffie of the gtod.
+ * But since we may be at the start of a jiffy or the end of one
+ * we add another jiffy buffer.
+ */
+ max_clock = scd->tick_gtod + (2 + delta_jiffies) * TICK_NSEC;
+
+ delta *= scd->multi;
+ delta >>= MULTI_SHIFT;
- if (unlikely(clock + delta > max_clock)) {
+ if (unlikely(clock + delta > max_clock) && check_max(scd)) {
if (clock < max_clock)
clock = max_clock;
else
@@ -118,9 +180,12 @@ static void __update_sched_clock(struct sched_clock_data *scd, u64 now)
if (unlikely(clock < min_clock))
clock = min_clock;
- scd->prev_raw = now;
- scd->prev_jiffies = now_jiffies;
- scd->clock = clock;
+ if (time)
+ *time = clock;
+ else {
+ scd->prev_raw = now;
+ scd->clock = clock;
+ }
}
static void lock_double_clock(struct sched_clock_data *data1,
@@ -160,25 +225,30 @@ u64 sched_clock_cpu(int cpu)
now -= my_scd->tick_raw;
now += scd->tick_raw;
- now -= my_scd->tick_gtod;
- now += scd->tick_gtod;
+ now += my_scd->tick_gtod;
+ now -= scd->tick_gtod;
__raw_spin_unlock(&my_scd->lock);
+
+ __update_sched_clock(scd, now, &clock);
+
+ __raw_spin_unlock(&scd->lock);
+
} else {
__raw_spin_lock(&scd->lock);
+ __update_sched_clock(scd, now, NULL);
+ clock = scd->clock;
+ __raw_spin_unlock(&scd->lock);
}
- __update_sched_clock(scd, now);
- clock = scd->clock;
-
- __raw_spin_unlock(&scd->lock);
-
return clock;
}
void sched_clock_tick(void)
{
struct sched_clock_data *scd = this_scd();
+ unsigned long now_jiffies = jiffies;
+ s64 mult, delta_gtod, delta_raw;
u64 now, now_gtod;
if (unlikely(!sched_clock_running))
@@ -186,18 +256,33 @@ void sched_clock_tick(void)
WARN_ON_ONCE(!irqs_disabled());
- now = sched_clock();
now_gtod = ktime_to_ns(ktime_get());
+ now = sched_clock();
__raw_spin_lock(&scd->lock);
- __update_sched_clock(scd, now);
+ __update_sched_clock(scd, now, NULL);
/*
* update tick_gtod after __update_sched_clock() because that will
* already observe 1 new jiffy; adding a new tick_gtod to that would
* increase the clock 2 jiffies.
*/
+ delta_gtod = now_gtod - scd->tick_gtod;
+ delta_raw = now - scd->tick_raw;
+
+ if ((long)delta_raw > 0) {
+ mult = delta_gtod << MULTI_SHIFT;
+ do_div(mult, delta_raw);
+ scd->multi = mult;
+ if (scd->multi > MAX_MULTI)
+ scd->multi = MAX_MULTI;
+ else if (scd->multi < MIN_MULTI)
+ scd->multi = MIN_MULTI;
+ } else
+ scd->multi = 1 << MULTI_SHIFT;
+
scd->tick_raw = now;
scd->tick_gtod = now_gtod;
+ scd->tick_jiffies = now_jiffies;
__raw_spin_unlock(&scd->lock);
}
@@ -227,6 +312,7 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
__raw_spin_lock(&scd->lock);
scd->prev_raw = now;
scd->clock += delta_ns;
+ scd->multi = 1 << MULTI_SHIFT;
__raw_spin_unlock(&scd->lock);
touch_softlockup_watchdog();
@@ -244,3 +330,16 @@ unsigned long long __attribute__((weak)) sched_clock(void)
{
return (unsigned long long)jiffies * (NSEC_PER_SEC / HZ);
}
+
+unsigned long long cpu_clock(int cpu)
+{
+ unsigned long long clock;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ clock = sched_clock_cpu(cpu);
+ local_irq_restore(flags);
+
+ return clock;
+}
+EXPORT_SYMBOL_GPL(cpu_clock);
diff --git a/kernel/sched_cpupri.c b/kernel/sched_cpupri.c
new file mode 100644
index 00000000000..52154fefab7
--- /dev/null
+++ b/kernel/sched_cpupri.c
@@ -0,0 +1,174 @@
+/*
+ * kernel/sched_cpupri.c
+ *
+ * CPU priority management
+ *
+ * Copyright (C) 2007-2008 Novell
+ *
+ * Author: Gregory Haskins <ghaskins@novell.com>
+ *
+ * This code tracks the priority of each CPU so that global migration
+ * decisions are easy to calculate. Each CPU can be in a state as follows:
+ *
+ * (INVALID), IDLE, NORMAL, RT1, ... RT99
+ *
+ * going from the lowest priority to the highest. CPUs in the INVALID state
+ * are not eligible for routing. The system maintains this state with
+ * a 2 dimensional bitmap (the first for priority class, the second for cpus
+ * in that class). Therefore a typical application without affinity
+ * restrictions can find a suitable CPU with O(1) complexity (e.g. two bit
+ * searches). For tasks with affinity restrictions, the algorithm has a
+ * worst case complexity of O(min(102, nr_domcpus)), though the scenario that
+ * yields the worst case search is fairly contrived.
+ *
+ * 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 "sched_cpupri.h"
+
+/* Convert between a 140 based task->prio, and our 102 based cpupri */
+static int convert_prio(int prio)
+{
+ int cpupri;
+
+ if (prio == CPUPRI_INVALID)
+ cpupri = CPUPRI_INVALID;
+ else if (prio == MAX_PRIO)
+ cpupri = CPUPRI_IDLE;
+ else if (prio >= MAX_RT_PRIO)
+ cpupri = CPUPRI_NORMAL;
+ else
+ cpupri = MAX_RT_PRIO - prio + 1;
+
+ return cpupri;
+}
+
+#define for_each_cpupri_active(array, idx) \
+ for (idx = find_first_bit(array, CPUPRI_NR_PRIORITIES); \
+ idx < CPUPRI_NR_PRIORITIES; \
+ idx = find_next_bit(array, CPUPRI_NR_PRIORITIES, idx+1))
+
+/**
+ * cpupri_find - find the best (lowest-pri) CPU in the system
+ * @cp: The cpupri context
+ * @p: The task
+ * @lowest_mask: A mask to fill in with selected CPUs
+ *
+ * Note: This function returns the recommended CPUs as calculated during the
+ * current invokation. By the time the call returns, the CPUs may have in
+ * fact changed priorities any number of times. While not ideal, it is not
+ * an issue of correctness since the normal rebalancer logic will correct
+ * any discrepancies created by racing against the uncertainty of the current
+ * priority configuration.
+ *
+ * Returns: (int)bool - CPUs were found
+ */
+int cpupri_find(struct cpupri *cp, struct task_struct *p,
+ cpumask_t *lowest_mask)
+{
+ int idx = 0;
+ int task_pri = convert_prio(p->prio);
+
+ for_each_cpupri_active(cp->pri_active, idx) {
+ struct cpupri_vec *vec = &cp->pri_to_cpu[idx];
+ cpumask_t mask;
+
+ if (idx >= task_pri)
+ break;
+
+ cpus_and(mask, p->cpus_allowed, vec->mask);
+
+ if (cpus_empty(mask))
+ continue;
+
+ *lowest_mask = mask;
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * cpupri_set - update the cpu priority setting
+ * @cp: The cpupri context
+ * @cpu: The target cpu
+ * @pri: The priority (INVALID-RT99) to assign to this CPU
+ *
+ * Note: Assumes cpu_rq(cpu)->lock is locked
+ *
+ * Returns: (void)
+ */
+void cpupri_set(struct cpupri *cp, int cpu, int newpri)
+{
+ int *currpri = &cp->cpu_to_pri[cpu];
+ int oldpri = *currpri;
+ unsigned long flags;
+
+ newpri = convert_prio(newpri);
+
+ BUG_ON(newpri >= CPUPRI_NR_PRIORITIES);
+
+ if (newpri == oldpri)
+ return;
+
+ /*
+ * If the cpu was currently mapped to a different value, we
+ * first need to unmap the old value
+ */
+ if (likely(oldpri != CPUPRI_INVALID)) {
+ struct cpupri_vec *vec = &cp->pri_to_cpu[oldpri];
+
+ spin_lock_irqsave(&vec->lock, flags);
+
+ vec->count--;
+ if (!vec->count)
+ clear_bit(oldpri, cp->pri_active);
+ cpu_clear(cpu, vec->mask);
+
+ spin_unlock_irqrestore(&vec->lock, flags);
+ }
+
+ if (likely(newpri != CPUPRI_INVALID)) {
+ struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
+
+ spin_lock_irqsave(&vec->lock, flags);
+
+ cpu_set(cpu, vec->mask);
+ vec->count++;
+ if (vec->count == 1)
+ set_bit(newpri, cp->pri_active);
+
+ spin_unlock_irqrestore(&vec->lock, flags);
+ }
+
+ *currpri = newpri;
+}
+
+/**
+ * cpupri_init - initialize the cpupri structure
+ * @cp: The cpupri context
+ *
+ * Returns: (void)
+ */
+void cpupri_init(struct cpupri *cp)
+{
+ int i;
+
+ memset(cp, 0, sizeof(*cp));
+
+ for (i = 0; i < CPUPRI_NR_PRIORITIES; i++) {
+ struct cpupri_vec *vec = &cp->pri_to_cpu[i];
+
+ spin_lock_init(&vec->lock);
+ vec->count = 0;
+ cpus_clear(vec->mask);
+ }
+
+ for_each_possible_cpu(i)
+ cp->cpu_to_pri[i] = CPUPRI_INVALID;
+}
+
+
diff --git a/kernel/sched_cpupri.h b/kernel/sched_cpupri.h
new file mode 100644
index 00000000000..f25811b0f93
--- /dev/null
+++ b/kernel/sched_cpupri.h
@@ -0,0 +1,36 @@
+#ifndef _LINUX_CPUPRI_H
+#define _LINUX_CPUPRI_H
+
+#include <linux/sched.h>
+
+#define CPUPRI_NR_PRIORITIES (MAX_RT_PRIO + 2)
+#define CPUPRI_NR_PRI_WORDS BITS_TO_LONGS(CPUPRI_NR_PRIORITIES)
+
+#define CPUPRI_INVALID -1
+#define CPUPRI_IDLE 0
+#define CPUPRI_NORMAL 1
+/* values 2-101 are RT priorities 0-99 */
+
+struct cpupri_vec {
+ spinlock_t lock;
+ int count;
+ cpumask_t mask;
+};
+
+struct cpupri {
+ struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
+ long pri_active[CPUPRI_NR_PRI_WORDS];
+ int cpu_to_pri[NR_CPUS];
+};
+
+#ifdef CONFIG_SMP
+int cpupri_find(struct cpupri *cp,
+ struct task_struct *p, cpumask_t *lowest_mask);
+void cpupri_set(struct cpupri *cp, int cpu, int pri);
+void cpupri_init(struct cpupri *cp);
+#else
+#define cpupri_set(cp, cpu, pri) do { } while (0)
+#define cpupri_init() do { } while (0)
+#endif
+
+#endif /* _LINUX_CPUPRI_H */
diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c
index 8bb713040ac..bbe6b31c3c5 100644
--- a/kernel/sched_debug.c
+++ b/kernel/sched_debug.c
@@ -119,9 +119,7 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
struct sched_entity *last;
unsigned long flags;
-#if !defined(CONFIG_CGROUP_SCHED) || !defined(CONFIG_USER_SCHED)
- SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
-#else
+#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
char path[128] = "";
struct cgroup *cgroup = NULL;
struct task_group *tg = cfs_rq->tg;
@@ -133,6 +131,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
cgroup_path(cgroup, path, sizeof(path));
SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
+#else
+ SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
#endif
SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock",
@@ -162,11 +162,64 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
#ifdef CONFIG_SCHEDSTATS
- SEQ_printf(m, " .%-30s: %d\n", "bkl_count",
- rq->bkl_count);
+#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
+
+ P(yld_exp_empty);
+ P(yld_act_empty);
+ P(yld_both_empty);
+ P(yld_count);
+
+ P(sched_switch);
+ P(sched_count);
+ P(sched_goidle);
+
+ P(ttwu_count);
+ P(ttwu_local);
+
+ P(bkl_count);
+
+#undef P
#endif
SEQ_printf(m, " .%-30s: %ld\n", "nr_spread_over",
cfs_rq->nr_spread_over);
+#ifdef CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_SMP
+ SEQ_printf(m, " .%-30s: %lu\n", "shares", cfs_rq->shares);
+#endif
+#endif
+}
+
+void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
+{
+#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
+ char path[128] = "";
+ struct cgroup *cgroup = NULL;
+ struct task_group *tg = rt_rq->tg;
+
+ if (tg)
+ cgroup = tg->css.cgroup;
+
+ if (cgroup)
+ cgroup_path(cgroup, path, sizeof(path));
+
+ SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
+#else
+ SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
+#endif
+
+
+#define P(x) \
+ SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
+#define PN(x) \
+ SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
+
+ P(rt_nr_running);
+ P(rt_throttled);
+ PN(rt_time);
+ PN(rt_runtime);
+
+#undef PN
+#undef P
}
static void print_cpu(struct seq_file *m, int cpu)
@@ -208,6 +261,7 @@ static void print_cpu(struct seq_file *m, int cpu)
#undef PN
print_cfs_stats(m, cpu);
+ print_rt_stats(m, cpu);
print_rq(m, rq, cpu);
}
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 08ae848b71d..f2aa987027d 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -63,13 +63,13 @@ unsigned int __read_mostly sysctl_sched_compat_yield;
/*
* SCHED_OTHER wake-up granularity.
- * (default: 10 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ * (default: 5 msec * (1 + ilog(ncpus)), units: nanoseconds)
*
* This option delays the preemption effects of decoupled workloads
* and reduces their over-scheduling. Synchronous workloads will still
* have immediate wakeup/sleep latencies.
*/
-unsigned int sysctl_sched_wakeup_granularity = 10000000UL;
+unsigned int sysctl_sched_wakeup_granularity = 5000000UL;
const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
@@ -334,6 +334,34 @@ int sched_nr_latency_handler(struct ctl_table *table, int write,
#endif
/*
+ * delta *= w / rw
+ */
+static inline unsigned long
+calc_delta_weight(unsigned long delta, struct sched_entity *se)
+{
+ for_each_sched_entity(se) {
+ delta = calc_delta_mine(delta,
+ se->load.weight, &cfs_rq_of(se)->load);
+ }
+
+ return delta;
+}
+
+/*
+ * delta *= rw / w
+ */
+static inline unsigned long
+calc_delta_fair(unsigned long delta, struct sched_entity *se)
+{
+ for_each_sched_entity(se) {
+ delta = calc_delta_mine(delta,
+ cfs_rq_of(se)->load.weight, &se->load);
+ }
+
+ return delta;
+}
+
+/*
* The idea is to set a period in which each task runs once.
*
* When there are too many tasks (sysctl_sched_nr_latency) we have to stretch
@@ -362,47 +390,80 @@ static u64 __sched_period(unsigned long nr_running)
*/
static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- u64 slice = __sched_period(cfs_rq->nr_running);
-
- for_each_sched_entity(se) {
- cfs_rq = cfs_rq_of(se);
-
- slice *= se->load.weight;
- do_div(slice, cfs_rq->load.weight);
- }
-
-
- return slice;
+ return calc_delta_weight(__sched_period(cfs_rq->nr_running), se);
}
/*
* We calculate the vruntime slice of a to be inserted task
*
- * vs = s/w = p/rw
+ * vs = s*rw/w = p
*/
static u64 sched_vslice_add(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
unsigned long nr_running = cfs_rq->nr_running;
- unsigned long weight;
- u64 vslice;
if (!se->on_rq)
nr_running++;
- vslice = __sched_period(nr_running);
+ return __sched_period(nr_running);
+}
+
+/*
+ * The goal of calc_delta_asym() is to be asymmetrically around NICE_0_LOAD, in
+ * that it favours >=0 over <0.
+ *
+ * -20 |
+ * |
+ * 0 --------+-------
+ * .'
+ * 19 .'
+ *
+ */
+static unsigned long
+calc_delta_asym(unsigned long delta, struct sched_entity *se)
+{
+ struct load_weight lw = {
+ .weight = NICE_0_LOAD,
+ .inv_weight = 1UL << (WMULT_SHIFT-NICE_0_SHIFT)
+ };
for_each_sched_entity(se) {
- cfs_rq = cfs_rq_of(se);
+ struct load_weight *se_lw = &se->load;
+ unsigned long rw = cfs_rq_of(se)->load.weight;
+
+#ifdef CONFIG_FAIR_SCHED_GROUP
+ struct cfs_rq *cfs_rq = se->my_q;
+ struct task_group *tg = NULL
+
+ if (cfs_rq)
+ tg = cfs_rq->tg;
+
+ if (tg && tg->shares < NICE_0_LOAD) {
+ /*
+ * scale shares to what it would have been had
+ * tg->weight been NICE_0_LOAD:
+ *
+ * weight = 1024 * shares / tg->weight
+ */
+ lw.weight *= se->load.weight;
+ lw.weight /= tg->shares;
+
+ lw.inv_weight = 0;
+
+ se_lw = &lw;
+ rw += lw.weight - se->load.weight;
+ } else
+#endif
- weight = cfs_rq->load.weight;
- if (!se->on_rq)
- weight += se->load.weight;
+ if (se->load.weight < NICE_0_LOAD) {
+ se_lw = &lw;
+ rw += NICE_0_LOAD - se->load.weight;
+ }
- vslice *= NICE_0_LOAD;
- do_div(vslice, weight);
+ delta = calc_delta_mine(delta, rw, se_lw);
}
- return vslice;
+ return delta;
}
/*
@@ -419,11 +480,7 @@ __update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
curr->sum_exec_runtime += delta_exec;
schedstat_add(cfs_rq, exec_clock, delta_exec);
- delta_exec_weighted = delta_exec;
- if (unlikely(curr->load.weight != NICE_0_LOAD)) {
- delta_exec_weighted = calc_delta_fair(delta_exec_weighted,
- &curr->load);
- }
+ delta_exec_weighted = calc_delta_fair(delta_exec, curr);
curr->vruntime += delta_exec_weighted;
}
@@ -510,10 +567,27 @@ update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
* Scheduling class queueing methods:
*/
+#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+static void
+add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
+{
+ cfs_rq->task_weight += weight;
+}
+#else
+static inline void
+add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
+{
+}
+#endif
+
static void
account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_add(&cfs_rq->load, se->load.weight);
+ if (!parent_entity(se))
+ inc_cpu_load(rq_of(cfs_rq), se->load.weight);
+ if (entity_is_task(se))
+ add_cfs_task_weight(cfs_rq, se->load.weight);
cfs_rq->nr_running++;
se->on_rq = 1;
list_add(&se->group_node, &cfs_rq->tasks);
@@ -523,6 +597,10 @@ static void
account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
update_load_sub(&cfs_rq->load, se->load.weight);
+ if (!parent_entity(se))
+ dec_cpu_load(rq_of(cfs_rq), se->load.weight);
+ if (entity_is_task(se))
+ add_cfs_task_weight(cfs_rq, -se->load.weight);
cfs_rq->nr_running--;
se->on_rq = 0;
list_del_init(&se->group_node);
@@ -609,8 +687,17 @@ 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))
- vruntime -= sysctl_sched_latency;
+ if (sched_feat(NEW_FAIR_SLEEPERS)) {
+ unsigned long thresh = sysctl_sched_latency;
+
+ /*
+ * convert the sleeper threshold into virtual time
+ */
+ if (sched_feat(NORMALIZED_SLEEPER))
+ thresh = calc_delta_fair(thresh, se);
+
+ vruntime -= thresh;
+ }
/* ensure we never gain time by being placed backwards. */
vruntime = max_vruntime(se->vruntime, vruntime);
@@ -639,21 +726,6 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int wakeup)
__enqueue_entity(cfs_rq, se);
}
-static void update_avg(u64 *avg, u64 sample)
-{
- s64 diff = sample - *avg;
- *avg += diff >> 3;
-}
-
-static void update_avg_stats(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- if (!se->last_wakeup)
- return;
-
- update_avg(&se->avg_overlap, se->sum_exec_runtime - se->last_wakeup);
- se->last_wakeup = 0;
-}
-
static void
dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
{
@@ -664,7 +736,6 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int sleep)
update_stats_dequeue(cfs_rq, se);
if (sleep) {
- update_avg_stats(cfs_rq, se);
#ifdef CONFIG_SCHEDSTATS
if (entity_is_task(se)) {
struct task_struct *tsk = task_of(se);
@@ -726,17 +797,16 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
se->prev_sum_exec_runtime = se->sum_exec_runtime;
}
-static int
-wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se);
-
static struct sched_entity *
pick_next(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- if (!cfs_rq->next)
- return se;
+ struct rq *rq = rq_of(cfs_rq);
+ u64 pair_slice = rq->clock - cfs_rq->pair_start;
- if (wakeup_preempt_entity(cfs_rq->next, se) != 0)
+ if (!cfs_rq->next || pair_slice > sched_slice(cfs_rq, cfs_rq->next)) {
+ cfs_rq->pair_start = rq->clock;
return se;
+ }
return cfs_rq->next;
}
@@ -835,7 +905,7 @@ static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
hrtick_start(rq, delta, requeue);
}
}
-#else
+#else /* !CONFIG_SCHED_HRTICK */
static inline void
hrtick_start_fair(struct rq *rq, struct task_struct *p)
{
@@ -976,7 +1046,7 @@ static int wake_idle(int cpu, struct task_struct *p)
}
return cpu;
}
-#else
+#else /* !ARCH_HAS_SCHED_WAKE_IDLE*/
static inline int wake_idle(int cpu, struct task_struct *p)
{
return cpu;
@@ -987,6 +1057,89 @@ static inline int wake_idle(int cpu, struct task_struct *p)
static const struct sched_class fair_sched_class;
+#ifdef CONFIG_FAIR_GROUP_SCHED
+/*
+ * effective_load() calculates the load change as seen from the root_task_group
+ *
+ * Adding load to a group doesn't make a group heavier, but can cause movement
+ * of group shares between cpus. Assuming the shares were perfectly aligned one
+ * can calculate the shift in shares.
+ *
+ * The problem is that perfectly aligning the shares is rather expensive, hence
+ * we try to avoid doing that too often - see update_shares(), which ratelimits
+ * this change.
+ *
+ * We compensate this by not only taking the current delta into account, but
+ * also considering the delta between when the shares were last adjusted and
+ * now.
+ *
+ * We still saw a performance dip, some tracing learned us that between
+ * cgroup:/ and cgroup:/foo balancing the number of affine wakeups increased
+ * significantly. Therefore try to bias the error in direction of failing
+ * the affine wakeup.
+ *
+ */
+static long effective_load(struct task_group *tg, int cpu,
+ long wl, long wg)
+{
+ struct sched_entity *se = tg->se[cpu];
+ long more_w;
+
+ if (!tg->parent)
+ return wl;
+
+ /*
+ * By not taking the decrease of shares on the other cpu into
+ * account our error leans towards reducing the affine wakeups.
+ */
+ if (!wl && sched_feat(ASYM_EFF_LOAD))
+ return wl;
+
+ /*
+ * Instead of using this increment, also add the difference
+ * between when the shares were last updated and now.
+ */
+ more_w = se->my_q->load.weight - se->my_q->rq_weight;
+ wl += more_w;
+ wg += more_w;
+
+ for_each_sched_entity(se) {
+#define D(n) (likely(n) ? (n) : 1)
+
+ long S, rw, s, a, b;
+
+ S = se->my_q->tg->shares;
+ s = se->my_q->shares;
+ rw = se->my_q->rq_weight;
+
+ a = S*(rw + wl);
+ b = S*rw + s*wg;
+
+ wl = s*(a-b)/D(b);
+ /*
+ * Assume the group is already running and will
+ * thus already be accounted for in the weight.
+ *
+ * That is, moving shares between CPUs, does not
+ * alter the group weight.
+ */
+ wg = 0;
+#undef D
+ }
+
+ return wl;
+}
+
+#else
+
+static inline unsigned long effective_load(struct task_group *tg, int cpu,
+ unsigned long wl, unsigned long wg)
+{
+ return wl;
+}
+
+#endif
+
static int
wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
struct task_struct *p, int prev_cpu, int this_cpu, int sync,
@@ -994,8 +1147,10 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
unsigned int imbalance)
{
struct task_struct *curr = this_rq->curr;
+ struct task_group *tg;
unsigned long tl = this_load;
unsigned long tl_per_task;
+ unsigned long weight;
int balanced;
if (!(this_sd->flags & SD_WAKE_AFFINE) || !sched_feat(AFFINE_WAKEUPS))
@@ -1006,19 +1161,28 @@ wake_affine(struct rq *rq, struct sched_domain *this_sd, struct rq *this_rq,
* effect of the currently running task from the load
* of the current CPU:
*/
- if (sync)
- tl -= current->se.load.weight;
+ if (sync) {
+ tg = task_group(current);
+ weight = current->se.load.weight;
+
+ tl += effective_load(tg, this_cpu, -weight, -weight);
+ load += effective_load(tg, prev_cpu, 0, -weight);
+ }
- balanced = 100*(tl + p->se.load.weight) <= imbalance*load;
+ tg = task_group(p);
+ weight = p->se.load.weight;
+
+ balanced = 100*(tl + effective_load(tg, this_cpu, weight, weight)) <=
+ imbalance*(load + effective_load(tg, prev_cpu, 0, weight));
/*
* If the currently running task will sleep within
* a reasonable amount of time then attract this newly
* woken task:
*/
- if (sync && balanced && curr->sched_class == &fair_sched_class) {
+ if (sync && balanced) {
if (curr->se.avg_overlap < sysctl_sched_migration_cost &&
- p->se.avg_overlap < sysctl_sched_migration_cost)
+ p->se.avg_overlap < sysctl_sched_migration_cost)
return 1;
}
@@ -1111,11 +1275,13 @@ static unsigned long wakeup_gran(struct sched_entity *se)
unsigned long gran = sysctl_sched_wakeup_granularity;
/*
- * More easily preempt - nice tasks, while not making
- * it harder for + nice tasks.
+ * 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 (sched_feat(ASYM_GRAN))
+ gran = calc_delta_asym(sysctl_sched_wakeup_granularity, se);
+ else
+ gran = calc_delta_fair(sysctl_sched_wakeup_granularity, se);
return gran;
}
@@ -1177,7 +1343,6 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
return;
}
- se->last_wakeup = se->sum_exec_runtime;
if (unlikely(se == pse))
return;
@@ -1275,23 +1440,18 @@ __load_balance_iterator(struct cfs_rq *cfs_rq, struct list_head *next)
struct task_struct *p = NULL;
struct sched_entity *se;
- if (next == &cfs_rq->tasks)
- return NULL;
-
- /* Skip over entities that are not tasks */
- do {
+ while (next != &cfs_rq->tasks) {
se = list_entry(next, struct sched_entity, group_node);
next = next->next;
- } while (next != &cfs_rq->tasks && !entity_is_task(se));
- if (next == &cfs_rq->tasks)
- return NULL;
+ /* Skip over entities that are not tasks */
+ if (entity_is_task(se)) {
+ p = task_of(se);
+ break;
+ }
+ }
cfs_rq->balance_iterator = next;
-
- if (entity_is_task(se))
- p = task_of(se);
-
return p;
}
@@ -1309,75 +1469,82 @@ static struct task_struct *load_balance_next_fair(void *arg)
return __load_balance_iterator(cfs_rq, cfs_rq->balance_iterator);
}
-#ifdef CONFIG_FAIR_GROUP_SCHED
-static int cfs_rq_best_prio(struct cfs_rq *cfs_rq)
+static unsigned long
+__load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
+ unsigned long max_load_move, struct sched_domain *sd,
+ enum cpu_idle_type idle, int *all_pinned, int *this_best_prio,
+ struct cfs_rq *cfs_rq)
{
- struct sched_entity *curr;
- struct task_struct *p;
-
- if (!cfs_rq->nr_running || !first_fair(cfs_rq))
- return MAX_PRIO;
-
- curr = cfs_rq->curr;
- if (!curr)
- curr = __pick_next_entity(cfs_rq);
+ struct rq_iterator cfs_rq_iterator;
- p = task_of(curr);
+ cfs_rq_iterator.start = load_balance_start_fair;
+ cfs_rq_iterator.next = load_balance_next_fair;
+ cfs_rq_iterator.arg = cfs_rq;
- return p->prio;
+ return balance_tasks(this_rq, this_cpu, busiest,
+ max_load_move, sd, idle, all_pinned,
+ this_best_prio, &cfs_rq_iterator);
}
-#endif
+#ifdef CONFIG_FAIR_GROUP_SCHED
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
struct sched_domain *sd, enum cpu_idle_type idle,
int *all_pinned, int *this_best_prio)
{
- struct cfs_rq *busy_cfs_rq;
long rem_load_move = max_load_move;
- struct rq_iterator cfs_rq_iterator;
-
- cfs_rq_iterator.start = load_balance_start_fair;
- cfs_rq_iterator.next = load_balance_next_fair;
+ int busiest_cpu = cpu_of(busiest);
+ struct task_group *tg;
- 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;
+ rcu_read_lock();
+ update_h_load(busiest_cpu);
- this_cfs_rq = cpu_cfs_rq(busy_cfs_rq, this_cpu);
+ list_for_each_entry(tg, &task_groups, list) {
+ struct cfs_rq *busiest_cfs_rq = tg->cfs_rq[busiest_cpu];
+ unsigned long busiest_h_load = busiest_cfs_rq->h_load;
+ unsigned long busiest_weight = busiest_cfs_rq->load.weight;
+ u64 rem_load, moved_load;
- 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)
+ /*
+ * empty group
+ */
+ if (!busiest_cfs_rq->task_weight)
continue;
- /* Don't pull more than imbalance/2 */
- imbalance /= 2;
- maxload = min(rem_load_move, imbalance);
+ rem_load = (u64)rem_load_move * busiest_weight;
+ rem_load = div_u64(rem_load, busiest_h_load + 1);
- *this_best_prio = cfs_rq_best_prio(this_cfs_rq);
-#else
-# define maxload rem_load_move
-#endif
- /*
- * pass busy_cfs_rq argument into
- * load_balance_[start|next]_fair iterators
- */
- cfs_rq_iterator.arg = busy_cfs_rq;
- rem_load_move -= balance_tasks(this_rq, this_cpu, busiest,
- maxload, sd, idle, all_pinned,
- this_best_prio,
- &cfs_rq_iterator);
+ moved_load = __load_balance_fair(this_rq, this_cpu, busiest,
+ rem_load, sd, idle, all_pinned, this_best_prio,
+ tg->cfs_rq[busiest_cpu]);
+
+ if (!moved_load)
+ continue;
+
+ moved_load *= busiest_h_load;
+ moved_load = div_u64(moved_load, busiest_weight + 1);
- if (rem_load_move <= 0)
+ rem_load_move -= moved_load;
+ if (rem_load_move < 0)
break;
}
+ rcu_read_unlock();
return max_load_move - rem_load_move;
}
+#else
+static unsigned long
+load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
+ unsigned long max_load_move,
+ struct sched_domain *sd, enum cpu_idle_type idle,
+ int *all_pinned, int *this_best_prio)
+{
+ return __load_balance_fair(this_rq, this_cpu, busiest,
+ max_load_move, sd, idle, all_pinned,
+ this_best_prio, &busiest->cfs);
+}
+#endif
static int
move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
@@ -1402,7 +1569,7 @@ move_one_task_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
return 0;
}
-#endif
+#endif /* CONFIG_SMP */
/*
* scheduler tick hitting a task of our scheduling class:
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 1c7283cb958..862b06bd560 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -1,4 +1,5 @@
SCHED_FEAT(NEW_FAIR_SLEEPERS, 1)
+SCHED_FEAT(NORMALIZED_SLEEPER, 1)
SCHED_FEAT(WAKEUP_PREEMPT, 1)
SCHED_FEAT(START_DEBIT, 1)
SCHED_FEAT(AFFINE_WAKEUPS, 1)
@@ -6,5 +7,7 @@ SCHED_FEAT(CACHE_HOT_BUDDY, 1)
SCHED_FEAT(SYNC_WAKEUPS, 1)
SCHED_FEAT(HRTICK, 1)
SCHED_FEAT(DOUBLE_TICK, 0)
-SCHED_FEAT(NORMALIZED_SLEEPER, 1)
-SCHED_FEAT(DEADLINE, 1)
+SCHED_FEAT(ASYM_GRAN, 1)
+SCHED_FEAT(LB_BIAS, 0)
+SCHED_FEAT(LB_WAKEUP_UPDATE, 1)
+SCHED_FEAT(ASYM_EFF_LOAD, 1)
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 0f3c19197fa..47ceac9e855 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -12,6 +12,9 @@ static inline int rt_overloaded(struct rq *rq)
static inline void rt_set_overload(struct rq *rq)
{
+ if (!rq->online)
+ return;
+
cpu_set(rq->cpu, rq->rd->rto_mask);
/*
* Make sure the mask is visible before we set
@@ -26,6 +29,9 @@ static inline void rt_set_overload(struct rq *rq)
static inline void rt_clear_overload(struct rq *rq)
{
+ if (!rq->online)
+ return;
+
/* the order here really doesn't matter */
atomic_dec(&rq->rd->rto_count);
cpu_clear(rq->cpu, rq->rd->rto_mask);
@@ -155,7 +161,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
return &rt_rq->tg->rt_bandwidth;
}
-#else
+#else /* !CONFIG_RT_GROUP_SCHED */
static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
{
@@ -220,49 +226,10 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
return &def_rt_bandwidth;
}
-#endif
-
-static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
-{
- int i, idle = 1;
- cpumask_t span;
-
- if (rt_b->rt_runtime == RUNTIME_INF)
- return 1;
-
- span = sched_rt_period_mask();
- for_each_cpu_mask(i, span) {
- int enqueue = 0;
- struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
- struct rq *rq = rq_of_rt_rq(rt_rq);
-
- spin_lock(&rq->lock);
- if (rt_rq->rt_time) {
- u64 runtime;
-
- spin_lock(&rt_rq->rt_runtime_lock);
- runtime = rt_rq->rt_runtime;
- rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
- if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
- rt_rq->rt_throttled = 0;
- enqueue = 1;
- }
- if (rt_rq->rt_time || rt_rq->rt_nr_running)
- idle = 0;
- spin_unlock(&rt_rq->rt_runtime_lock);
- } else if (rt_rq->rt_nr_running)
- idle = 0;
-
- if (enqueue)
- sched_rt_rq_enqueue(rt_rq);
- spin_unlock(&rq->lock);
- }
-
- return idle;
-}
+#endif /* CONFIG_RT_GROUP_SCHED */
#ifdef CONFIG_SMP
-static int balance_runtime(struct rt_rq *rt_rq)
+static int do_balance_runtime(struct rt_rq *rt_rq)
{
struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
@@ -281,6 +248,9 @@ static int balance_runtime(struct rt_rq *rt_rq)
continue;
spin_lock(&iter->rt_runtime_lock);
+ if (iter->rt_runtime == RUNTIME_INF)
+ goto next;
+
diff = iter->rt_runtime - iter->rt_time;
if (diff > 0) {
do_div(diff, weight);
@@ -294,13 +264,163 @@ static int balance_runtime(struct rt_rq *rt_rq)
break;
}
}
+next:
spin_unlock(&iter->rt_runtime_lock);
}
spin_unlock(&rt_b->rt_runtime_lock);
return more;
}
-#endif
+
+static void __disable_runtime(struct rq *rq)
+{
+ struct root_domain *rd = rq->rd;
+ struct rt_rq *rt_rq;
+
+ if (unlikely(!scheduler_running))
+ return;
+
+ for_each_leaf_rt_rq(rt_rq, rq) {
+ struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+ s64 want;
+ int i;
+
+ spin_lock(&rt_b->rt_runtime_lock);
+ spin_lock(&rt_rq->rt_runtime_lock);
+ if (rt_rq->rt_runtime == RUNTIME_INF ||
+ rt_rq->rt_runtime == rt_b->rt_runtime)
+ goto balanced;
+ spin_unlock(&rt_rq->rt_runtime_lock);
+
+ want = rt_b->rt_runtime - rt_rq->rt_runtime;
+
+ for_each_cpu_mask(i, rd->span) {
+ struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
+ s64 diff;
+
+ if (iter == rt_rq)
+ continue;
+
+ spin_lock(&iter->rt_runtime_lock);
+ if (want > 0) {
+ diff = min_t(s64, iter->rt_runtime, want);
+ iter->rt_runtime -= diff;
+ want -= diff;
+ } else {
+ iter->rt_runtime -= want;
+ want -= want;
+ }
+ spin_unlock(&iter->rt_runtime_lock);
+
+ if (!want)
+ break;
+ }
+
+ spin_lock(&rt_rq->rt_runtime_lock);
+ BUG_ON(want);
+balanced:
+ rt_rq->rt_runtime = RUNTIME_INF;
+ spin_unlock(&rt_rq->rt_runtime_lock);
+ spin_unlock(&rt_b->rt_runtime_lock);
+ }
+}
+
+static void disable_runtime(struct rq *rq)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ __disable_runtime(rq);
+ spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+static void __enable_runtime(struct rq *rq)
+{
+ struct rt_rq *rt_rq;
+
+ if (unlikely(!scheduler_running))
+ return;
+
+ for_each_leaf_rt_rq(rt_rq, rq) {
+ struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+
+ spin_lock(&rt_b->rt_runtime_lock);
+ spin_lock(&rt_rq->rt_runtime_lock);
+ rt_rq->rt_runtime = rt_b->rt_runtime;
+ rt_rq->rt_time = 0;
+ spin_unlock(&rt_rq->rt_runtime_lock);
+ spin_unlock(&rt_b->rt_runtime_lock);
+ }
+}
+
+static void enable_runtime(struct rq *rq)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rq->lock, flags);
+ __enable_runtime(rq);
+ spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+static int balance_runtime(struct rt_rq *rt_rq)
+{
+ int more = 0;
+
+ if (rt_rq->rt_time > rt_rq->rt_runtime) {
+ spin_unlock(&rt_rq->rt_runtime_lock);
+ more = do_balance_runtime(rt_rq);
+ spin_lock(&rt_rq->rt_runtime_lock);
+ }
+
+ return more;
+}
+#else /* !CONFIG_SMP */
+static inline int balance_runtime(struct rt_rq *rt_rq)
+{
+ return 0;
+}
+#endif /* CONFIG_SMP */
+
+static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
+{
+ int i, idle = 1;
+ cpumask_t span;
+
+ if (rt_b->rt_runtime == RUNTIME_INF)
+ return 1;
+
+ span = sched_rt_period_mask();
+ for_each_cpu_mask(i, span) {
+ int enqueue = 0;
+ struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
+ struct rq *rq = rq_of_rt_rq(rt_rq);
+
+ spin_lock(&rq->lock);
+ if (rt_rq->rt_time) {
+ u64 runtime;
+
+ spin_lock(&rt_rq->rt_runtime_lock);
+ if (rt_rq->rt_throttled)
+ balance_runtime(rt_rq);
+ runtime = rt_rq->rt_runtime;
+ rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
+ if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
+ rt_rq->rt_throttled = 0;
+ enqueue = 1;
+ }
+ if (rt_rq->rt_time || rt_rq->rt_nr_running)
+ idle = 0;
+ spin_unlock(&rt_rq->rt_runtime_lock);
+ } else if (rt_rq->rt_nr_running)
+ idle = 0;
+
+ if (enqueue)
+ sched_rt_rq_enqueue(rt_rq);
+ spin_unlock(&rq->lock);
+ }
+
+ return idle;
+}
static inline int rt_se_prio(struct sched_rt_entity *rt_se)
{
@@ -327,18 +447,10 @@ static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
if (sched_rt_runtime(rt_rq) >= sched_rt_period(rt_rq))
return 0;
-#ifdef CONFIG_SMP
- if (rt_rq->rt_time > runtime) {
- int more;
-
- spin_unlock(&rt_rq->rt_runtime_lock);
- more = balance_runtime(rt_rq);
- spin_lock(&rt_rq->rt_runtime_lock);
-
- if (more)
- runtime = sched_rt_runtime(rt_rq);
- }
-#endif
+ balance_runtime(rt_rq);
+ runtime = sched_rt_runtime(rt_rq);
+ if (runtime == RUNTIME_INF)
+ return 0;
if (rt_rq->rt_time > runtime) {
rt_rq->rt_throttled = 1;
@@ -392,12 +504,21 @@ 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_RT_GROUP_SCHED
- if (rt_se_prio(rt_se) < rt_rq->highest_prio)
+ if (rt_se_prio(rt_se) < rt_rq->highest_prio) {
+ struct rq *rq = rq_of_rt_rq(rt_rq);
+
rt_rq->highest_prio = rt_se_prio(rt_se);
+#ifdef CONFIG_SMP
+ if (rq->online)
+ cpupri_set(&rq->rd->cpupri, rq->cpu,
+ rt_se_prio(rt_se));
+#endif
+ }
#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++;
}
@@ -417,6 +538,10 @@ void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
static inline
void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
{
+#ifdef CONFIG_SMP
+ int highest_prio = rt_rq->highest_prio;
+#endif
+
WARN_ON(!rt_prio(rt_se_prio(rt_se)));
WARN_ON(!rt_rq->rt_nr_running);
rt_rq->rt_nr_running--;
@@ -440,6 +565,14 @@ void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
rq->rt.rt_nr_migratory--;
}
+ if (rt_rq->highest_prio != highest_prio) {
+ struct rq *rq = rq_of_rt_rq(rt_rq);
+
+ if (rq->online)
+ cpupri_set(&rq->rd->cpupri, rq->cpu,
+ rt_rq->highest_prio);
+ }
+
update_rt_migration(rq_of_rt_rq(rt_rq));
#endif /* CONFIG_SMP */
#ifdef CONFIG_RT_GROUP_SCHED
@@ -455,6 +588,7 @@ 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);
+ struct list_head *queue = array->queue + rt_se_prio(rt_se);
/*
* Don't enqueue the group if its throttled, or when empty.
@@ -465,7 +599,11 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se)
if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
return;
- list_add_tail(&rt_se->run_list, array->queue + rt_se_prio(rt_se));
+ if (rt_se->nr_cpus_allowed == 1)
+ list_add(&rt_se->run_list, queue);
+ else
+ list_add_tail(&rt_se->run_list, queue);
+
__set_bit(rt_se_prio(rt_se), array->bitmap);
inc_rt_tasks(rt_se, rt_rq);
@@ -532,6 +670,8 @@ static void enqueue_task_rt(struct rq *rq, struct task_struct *p, int wakeup)
rt_se->timeout = 0;
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)
@@ -540,6 +680,8 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int sleep)
update_curr_rt(rq);
dequeue_rt_entity(rt_se);
+
+ dec_cpu_load(rq, p->se.load.weight);
}
/*
@@ -550,10 +692,12 @@ static
void requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se)
{
struct rt_prio_array *array = &rt_rq->active;
- struct list_head *queue = array->queue + rt_se_prio(rt_se);
- if (on_rt_rq(rt_se))
- list_move_tail(&rt_se->run_list, queue);
+ if (on_rt_rq(rt_se)) {
+ list_del_init(&rt_se->run_list);
+ list_add_tail(&rt_se->run_list,
+ array->queue + rt_se_prio(rt_se));
+ }
}
static void requeue_task_rt(struct rq *rq, struct task_struct *p)
@@ -616,8 +760,37 @@ static int select_task_rq_rt(struct task_struct *p, int sync)
*/
static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p)
{
- if (p->prio < rq->curr->prio)
+ if (p->prio < rq->curr->prio) {
resched_task(rq->curr);
+ return;
+ }
+
+#ifdef CONFIG_SMP
+ /*
+ * If:
+ *
+ * - the newly woken task is of equal priority to the current task
+ * - the newly woken task is non-migratable while current is migratable
+ * - current will be preempted on the next reschedule
+ *
+ * we should check to see if current can readily move to a different
+ * cpu. If so, we will reschedule to allow the push logic to try
+ * to move current somewhere else, making room for our non-migratable
+ * task.
+ */
+ if((p->prio == rq->curr->prio)
+ && p->rt.nr_cpus_allowed == 1
+ && rq->curr->rt.nr_cpus_allowed != 1) {
+ cpumask_t mask;
+
+ if (cpupri_find(&rq->rd->cpupri, rq->curr, &mask))
+ /*
+ * There appears to be other cpus that can accept
+ * current, so lets reschedule to try and push it away
+ */
+ resched_task(rq->curr);
+ }
+#endif
}
static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
@@ -720,73 +893,6 @@ static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
static DEFINE_PER_CPU(cpumask_t, local_cpu_mask);
-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;
-
- cpus_and(*lowest_mask, task_rq(task)->rd->online, task->cpus_allowed);
-
- /*
- * Scan each rq for the lowest prio.
- */
- for_each_cpu_mask(cpu, *lowest_mask) {
- struct rq *rq = cpu_rq(cpu);
-
- /* 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 inline int pick_optimal_cpu(int this_cpu, cpumask_t *mask)
{
int first;
@@ -808,17 +914,12 @@ static int find_lowest_rq(struct task_struct *task)
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 */
+ if (task->rt.nr_cpus_allowed == 1)
+ return -1; /* No other targets possible */
- /*
- * There is no sense in performing an optimal search if only one
- * target is found.
- */
- if (count == 1)
- return first_cpu(*lowest_mask);
+ if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
+ return -1; /* No targets found */
/*
* At this point we have built a mask of cpus representing the
@@ -1163,17 +1264,25 @@ static void set_cpus_allowed_rt(struct task_struct *p,
}
/* Assumes rq->lock is held */
-static void join_domain_rt(struct rq *rq)
+static void rq_online_rt(struct rq *rq)
{
if (rq->rt.overloaded)
rt_set_overload(rq);
+
+ __enable_runtime(rq);
+
+ cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio);
}
/* Assumes rq->lock is held */
-static void leave_domain_rt(struct rq *rq)
+static void rq_offline_rt(struct rq *rq)
{
if (rq->rt.overloaded)
rt_clear_overload(rq);
+
+ __disable_runtime(rq);
+
+ cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_INVALID);
}
/*
@@ -1336,8 +1445,8 @@ static const struct sched_class rt_sched_class = {
.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,
+ .rq_online = rq_online_rt,
+ .rq_offline = rq_offline_rt,
.pre_schedule = pre_schedule_rt,
.post_schedule = post_schedule_rt,
.task_wake_up = task_wake_up_rt,
@@ -1350,3 +1459,17 @@ static const struct sched_class rt_sched_class = {
.prio_changed = prio_changed_rt,
.switched_to = switched_to_rt,
};
+
+#ifdef CONFIG_SCHED_DEBUG
+extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
+
+static void print_rt_stats(struct seq_file *m, int cpu)
+{
+ struct rt_rq *rt_rq;
+
+ rcu_read_lock();
+ for_each_leaf_rt_rq(rt_rq, cpu_rq(cpu))
+ print_rt_rq(m, cpu, rt_rq);
+ rcu_read_unlock();
+}
+#endif /* CONFIG_SCHED_DEBUG */
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index 80179ef7450..8385d43987e 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -118,6 +118,13 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
if (rq)
rq->rq_sched_info.cpu_time += delta;
}
+
+static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{
+ if (rq)
+ rq->rq_sched_info.run_delay += delta;
+}
# define schedstat_inc(rq, field) do { (rq)->field++; } while (0)
# define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0)
# define schedstat_set(var, val) do { var = (val); } while (0)
@@ -126,6 +133,9 @@ static inline void
rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
{}
static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{}
+static inline void
rq_sched_info_depart(struct rq *rq, unsigned long long delta)
{}
# define schedstat_inc(rq, field) do { } while (0)
@@ -134,6 +144,11 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
#endif
#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+static inline void sched_info_reset_dequeued(struct task_struct *t)
+{
+ t->sched_info.last_queued = 0;
+}
+
/*
* Called when a process is dequeued from the active array and given
* the cpu. We should note that with the exception of interactive
@@ -143,15 +158,22 @@ rq_sched_info_depart(struct rq *rq, unsigned long long delta)
* active queue, thus delaying tasks in the expired queue from running;
* see scheduler_tick()).
*
- * This function is only called from sched_info_arrive(), rather than
- * dequeue_task(). Even though a task may be queued and dequeued multiple
- * times as it is shuffled about, we're really interested in knowing how
- * long it was from the *first* time it was queued to the time that it
- * finally hit a cpu.
+ * Though we are interested in knowing how long it was from the *first* time a
+ * task was queued to the time that it finally hit a cpu, we call this routine
+ * from dequeue_task() to account for possible rq->clock skew across cpus. The
+ * delta taken on each cpu would annul the skew.
*/
static inline void sched_info_dequeued(struct task_struct *t)
{
- t->sched_info.last_queued = 0;
+ unsigned long long now = task_rq(t)->clock, delta = 0;
+
+ if (unlikely(sched_info_on()))
+ if (t->sched_info.last_queued)
+ delta = now - t->sched_info.last_queued;
+ sched_info_reset_dequeued(t);
+ t->sched_info.run_delay += delta;
+
+ rq_sched_info_dequeued(task_rq(t), delta);
}
/*
@@ -165,7 +187,7 @@ static void sched_info_arrive(struct task_struct *t)
if (t->sched_info.last_queued)
delta = now - t->sched_info.last_queued;
- sched_info_dequeued(t);
+ sched_info_reset_dequeued(t);
t->sched_info.run_delay += delta;
t->sched_info.last_arrival = now;
t->sched_info.pcount++;
@@ -242,7 +264,9 @@ sched_info_switch(struct task_struct *prev, struct task_struct *next)
__sched_info_switch(prev, next);
}
#else
-#define sched_info_queued(t) do { } while (0)
-#define sched_info_switch(t, next) do { } while (0)
+#define sched_info_queued(t) do { } while (0)
+#define sched_info_reset_dequeued(t) do { } while (0)
+#define sched_info_dequeued(t) do { } while (0)
+#define sched_info_switch(t, next) do { } while (0)
#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */
diff --git a/kernel/semaphore.c b/kernel/semaphore.c
index 5c2942e768c..aaaeae8244e 100644
--- a/kernel/semaphore.c
+++ b/kernel/semaphore.c
@@ -31,6 +31,7 @@
#include <linux/sched.h>
#include <linux/semaphore.h>
#include <linux/spinlock.h>
+#include <linux/ftrace.h>
static noinline void __down(struct semaphore *sem);
static noinline int __down_interruptible(struct semaphore *sem);
diff --git a/kernel/softlockup.c b/kernel/softlockup.c
index c828c2339cc..a272d78185e 100644
--- a/kernel/softlockup.c
+++ b/kernel/softlockup.c
@@ -120,6 +120,7 @@ void softlockup_tick(void)
printk(KERN_ERR "BUG: soft lockup - CPU#%d stuck for %lus! [%s:%d]\n",
this_cpu, now - touch_timestamp,
current->comm, task_pid_nr(current));
+ print_modules();
if (regs)
show_regs(regs);
else
diff --git a/kernel/spinlock.c b/kernel/spinlock.c
index ae28c824512..a1fb54c93cd 100644
--- a/kernel/spinlock.c
+++ b/kernel/spinlock.c
@@ -436,7 +436,7 @@ int __lockfunc _spin_trylock_bh(spinlock_t *lock)
}
EXPORT_SYMBOL(_spin_trylock_bh);
-int in_lock_functions(unsigned long addr)
+notrace int in_lock_functions(unsigned long addr)
{
/* Linker adds these: start and end of __lockfunc functions */
extern char __lock_text_start[], __lock_text_end[];
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 29116652dca..18943985dde 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -46,6 +46,7 @@
#include <linux/nfs_fs.h>
#include <linux/acpi.h>
#include <linux/reboot.h>
+#include <linux/ftrace.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
@@ -266,6 +267,14 @@ static struct ctl_table kern_table[] = {
},
{
.ctl_name = CTL_UNNUMBERED,
+ .procname = "sched_shares_ratelimit",
+ .data = &sysctl_sched_shares_ratelimit,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ {
+ .ctl_name = CTL_UNNUMBERED,
.procname = "sched_child_runs_first",
.data = &sysctl_sched_child_runs_first,
.maxlen = sizeof(unsigned int),
@@ -455,6 +464,16 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
+#ifdef CONFIG_FTRACE
+ {
+ .ctl_name = CTL_UNNUMBERED,
+ .procname = "ftrace_enabled",
+ .data = &ftrace_enabled,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &ftrace_enable_sysctl,
+ },
+#endif
#ifdef CONFIG_KMOD
{
.ctl_name = KERN_MODPROBE,
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 57a1f02e5ec..67f80c26170 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -30,6 +30,7 @@
struct tick_device tick_broadcast_device;
static cpumask_t tick_broadcast_mask;
static DEFINE_SPINLOCK(tick_broadcast_lock);
+static int tick_broadcast_force;
#ifdef CONFIG_TICK_ONESHOT
static void tick_broadcast_clear_oneshot(int cpu);
@@ -232,10 +233,11 @@ static void tick_do_broadcast_on_off(void *why)
CLOCK_EVT_MODE_SHUTDOWN);
}
if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
- dev->features |= CLOCK_EVT_FEAT_DUMMY;
+ tick_broadcast_force = 1;
break;
case CLOCK_EVT_NOTIFY_BROADCAST_OFF:
- if (cpu_isset(cpu, tick_broadcast_mask)) {
+ if (!tick_broadcast_force &&
+ cpu_isset(cpu, tick_broadcast_mask)) {
cpu_clear(cpu, tick_broadcast_mask);
if (td->mode == TICKDEV_MODE_PERIODIC)
tick_setup_periodic(dev, 0);
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index b854a895591..d63008b09a4 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -276,6 +276,7 @@ void tick_nohz_stop_sched_tick(void)
ts->tick_stopped = 1;
ts->idle_jiffies = last_jiffies;
rcu_enter_nohz();
+ sched_clock_tick_stop(cpu);
}
/*
@@ -375,6 +376,7 @@ void tick_nohz_restart_sched_tick(void)
select_nohz_load_balancer(0);
now = ktime_get();
tick_do_update_jiffies64(now);
+ sched_clock_tick_start(cpu);
cpu_clear(cpu, nohz_cpu_mask);
/*
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
new file mode 100644
index 00000000000..263e9e6bbd6
--- /dev/null
+++ b/kernel/trace/Kconfig
@@ -0,0 +1,135 @@
+#
+# Architectures that offer an FTRACE implementation should select HAVE_FTRACE:
+#
+config HAVE_FTRACE
+ bool
+
+config HAVE_DYNAMIC_FTRACE
+ bool
+
+config TRACER_MAX_TRACE
+ bool
+
+config TRACING
+ bool
+ select DEBUG_FS
+ select STACKTRACE
+
+config FTRACE
+ bool "Kernel Function Tracer"
+ depends on HAVE_FTRACE
+ select FRAME_POINTER
+ select TRACING
+ select CONTEXT_SWITCH_TRACER
+ help
+ Enable the kernel to trace every kernel function. This is done
+ by using a compiler feature to insert a small, 5-byte No-Operation
+ instruction to the beginning of every kernel function, which NOP
+ sequence is then dynamically patched into a tracer call when
+ tracing is enabled by the administrator. If it's runtime disabled
+ (the bootup default), then the overhead of the instructions is very
+ small and not measurable even in micro-benchmarks.
+
+config IRQSOFF_TRACER
+ bool "Interrupts-off Latency Tracer"
+ default n
+ depends on TRACE_IRQFLAGS_SUPPORT
+ depends on GENERIC_TIME
+ depends on HAVE_FTRACE
+ select TRACE_IRQFLAGS
+ select TRACING
+ select TRACER_MAX_TRACE
+ help
+ This option measures the time spent in irqs-off critical
+ sections, with microsecond accuracy.
+
+ The default measurement method is a maximum search, which is
+ disabled by default and can be runtime (re-)started
+ via:
+
+ echo 0 > /debugfs/tracing/tracing_max_latency
+
+ (Note that kernel size and overhead increases with this option
+ enabled. This option and the preempt-off timing option can be
+ used together or separately.)
+
+config PREEMPT_TRACER
+ bool "Preemption-off Latency Tracer"
+ default n
+ depends on GENERIC_TIME
+ depends on PREEMPT
+ depends on HAVE_FTRACE
+ select TRACING
+ select TRACER_MAX_TRACE
+ help
+ This option measures the time spent in preemption off critical
+ sections, with microsecond accuracy.
+
+ The default measurement method is a maximum search, which is
+ disabled by default and can be runtime (re-)started
+ via:
+
+ echo 0 > /debugfs/tracing/tracing_max_latency
+
+ (Note that kernel size and overhead increases with this option
+ enabled. This option and the irqs-off timing option can be
+ used together or separately.)
+
+config SYSPROF_TRACER
+ bool "Sysprof Tracer"
+ depends on X86
+ select TRACING
+ help
+ This tracer provides the trace needed by the 'Sysprof' userspace
+ tool.
+
+config SCHED_TRACER
+ bool "Scheduling Latency Tracer"
+ depends on HAVE_FTRACE
+ select TRACING
+ select CONTEXT_SWITCH_TRACER
+ select TRACER_MAX_TRACE
+ help
+ This tracer tracks the latency of the highest priority task
+ to be scheduled in, starting from the point it has woken up.
+
+config CONTEXT_SWITCH_TRACER
+ bool "Trace process context switches"
+ depends on HAVE_FTRACE
+ select TRACING
+ select MARKERS
+ help
+ This tracer gets called from the context switch and records
+ all switching of tasks.
+
+config DYNAMIC_FTRACE
+ bool "enable/disable ftrace tracepoints dynamically"
+ depends on FTRACE
+ depends on HAVE_DYNAMIC_FTRACE
+ default y
+ help
+ This option will modify all the calls to ftrace dynamically
+ (will patch them out of the binary image and replaces them
+ with a No-Op instruction) as they are called. A table is
+ created to dynamically enable them again.
+
+ This way a CONFIG_FTRACE kernel is slightly larger, but otherwise
+ has native performance as long as no tracing is active.
+
+ The changes to the code are done by a kernel thread that
+ wakes up once a second and checks to see if any ftrace calls
+ were made. If so, it runs stop_machine (stops all CPUS)
+ and modifies the code to jump over the call to ftrace.
+
+config FTRACE_SELFTEST
+ bool
+
+config FTRACE_STARTUP_TEST
+ bool "Perform a startup test on ftrace"
+ depends on TRACING
+ select FTRACE_SELFTEST
+ help
+ This option performs a series of startup tests on ftrace. On bootup
+ a series of tests are made to verify that the tracer is
+ functioning properly. It will do tests on all the configured
+ tracers of ftrace.
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
new file mode 100644
index 00000000000..71d17de1728
--- /dev/null
+++ b/kernel/trace/Makefile
@@ -0,0 +1,24 @@
+
+# Do not instrument the tracer itself:
+
+ifdef CONFIG_FTRACE
+ORIG_CFLAGS := $(KBUILD_CFLAGS)
+KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
+
+# selftest needs instrumentation
+CFLAGS_trace_selftest_dynamic.o = -pg
+obj-y += trace_selftest_dynamic.o
+endif
+
+obj-$(CONFIG_FTRACE) += libftrace.o
+
+obj-$(CONFIG_TRACING) += trace.o
+obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
+obj-$(CONFIG_SYSPROF_TRACER) += trace_sysprof.o
+obj-$(CONFIG_FTRACE) += trace_functions.o
+obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
+obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
+obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
+obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
+
+libftrace-y := ftrace.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
new file mode 100644
index 00000000000..4231a3dc224
--- /dev/null
+++ b/kernel/trace/ftrace.c
@@ -0,0 +1,1727 @@
+/*
+ * Infrastructure for profiling code inserted by 'gcc -pg'.
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2004-2008 Ingo Molnar <mingo@redhat.com>
+ *
+ * Originally ported from the -rt patch by:
+ * Copyright (C) 2007 Arnaldo Carvalho de Melo <acme@redhat.com>
+ *
+ * Based on code in the latency_tracer, that is:
+ *
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 William Lee Irwin III
+ */
+
+#include <linux/stop_machine.h>
+#include <linux/clocksource.h>
+#include <linux/kallsyms.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/hardirq.h>
+#include <linux/kthread.h>
+#include <linux/uaccess.h>
+#include <linux/kprobes.h>
+#include <linux/ftrace.h>
+#include <linux/sysctl.h>
+#include <linux/ctype.h>
+#include <linux/hash.h>
+#include <linux/list.h>
+
+#include <asm/ftrace.h>
+
+#include "trace.h"
+
+/* ftrace_enabled is a method to turn ftrace on or off */
+int ftrace_enabled __read_mostly;
+static int last_ftrace_enabled;
+
+/*
+ * ftrace_disabled is set when an anomaly is discovered.
+ * ftrace_disabled is much stronger than ftrace_enabled.
+ */
+static int ftrace_disabled __read_mostly;
+
+static DEFINE_SPINLOCK(ftrace_lock);
+static DEFINE_MUTEX(ftrace_sysctl_lock);
+
+static struct ftrace_ops ftrace_list_end __read_mostly =
+{
+ .func = ftrace_stub,
+};
+
+static struct ftrace_ops *ftrace_list __read_mostly = &ftrace_list_end;
+ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
+
+static void ftrace_list_func(unsigned long ip, unsigned long parent_ip)
+{
+ struct ftrace_ops *op = ftrace_list;
+
+ /* in case someone actually ports this to alpha! */
+ read_barrier_depends();
+
+ while (op != &ftrace_list_end) {
+ /* silly alpha */
+ read_barrier_depends();
+ op->func(ip, parent_ip);
+ op = op->next;
+ };
+}
+
+/**
+ * clear_ftrace_function - reset the ftrace function
+ *
+ * This NULLs the ftrace function and in essence stops
+ * tracing. There may be lag
+ */
+void clear_ftrace_function(void)
+{
+ ftrace_trace_function = ftrace_stub;
+}
+
+static int __register_ftrace_function(struct ftrace_ops *ops)
+{
+ /* Should never be called by interrupts */
+ spin_lock(&ftrace_lock);
+
+ ops->next = ftrace_list;
+ /*
+ * We are entering ops into the ftrace_list but another
+ * CPU might be walking that list. We need to make sure
+ * the ops->next pointer is valid before another CPU sees
+ * the ops pointer included into the ftrace_list.
+ */
+ smp_wmb();
+ ftrace_list = ops;
+
+ if (ftrace_enabled) {
+ /*
+ * For one func, simply call it directly.
+ * For more than one func, call the chain.
+ */
+ if (ops->next == &ftrace_list_end)
+ ftrace_trace_function = ops->func;
+ else
+ ftrace_trace_function = ftrace_list_func;
+ }
+
+ spin_unlock(&ftrace_lock);
+
+ return 0;
+}
+
+static int __unregister_ftrace_function(struct ftrace_ops *ops)
+{
+ struct ftrace_ops **p;
+ int ret = 0;
+
+ spin_lock(&ftrace_lock);
+
+ /*
+ * If we are removing the last function, then simply point
+ * to the ftrace_stub.
+ */
+ if (ftrace_list == ops && ops->next == &ftrace_list_end) {
+ ftrace_trace_function = ftrace_stub;
+ ftrace_list = &ftrace_list_end;
+ goto out;
+ }
+
+ for (p = &ftrace_list; *p != &ftrace_list_end; p = &(*p)->next)
+ if (*p == ops)
+ break;
+
+ if (*p != ops) {
+ ret = -1;
+ goto out;
+ }
+
+ *p = (*p)->next;
+
+ if (ftrace_enabled) {
+ /* If we only have one func left, then call that directly */
+ if (ftrace_list == &ftrace_list_end ||
+ ftrace_list->next == &ftrace_list_end)
+ ftrace_trace_function = ftrace_list->func;
+ }
+
+ out:
+ spin_unlock(&ftrace_lock);
+
+ return ret;
+}
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+static struct task_struct *ftraced_task;
+
+enum {
+ FTRACE_ENABLE_CALLS = (1 << 0),
+ FTRACE_DISABLE_CALLS = (1 << 1),
+ FTRACE_UPDATE_TRACE_FUNC = (1 << 2),
+ FTRACE_ENABLE_MCOUNT = (1 << 3),
+ FTRACE_DISABLE_MCOUNT = (1 << 4),
+};
+
+static int ftrace_filtered;
+static int tracing_on;
+static int frozen_record_count;
+
+static struct hlist_head ftrace_hash[FTRACE_HASHSIZE];
+
+static DEFINE_PER_CPU(int, ftrace_shutdown_disable_cpu);
+
+static DEFINE_SPINLOCK(ftrace_shutdown_lock);
+static DEFINE_MUTEX(ftraced_lock);
+static DEFINE_MUTEX(ftrace_regex_lock);
+
+struct ftrace_page {
+ struct ftrace_page *next;
+ unsigned long index;
+ struct dyn_ftrace records[];
+};
+
+#define ENTRIES_PER_PAGE \
+ ((PAGE_SIZE - sizeof(struct ftrace_page)) / sizeof(struct dyn_ftrace))
+
+/* estimate from running different kernels */
+#define NR_TO_INIT 10000
+
+static struct ftrace_page *ftrace_pages_start;
+static struct ftrace_page *ftrace_pages;
+
+static int ftraced_trigger;
+static int ftraced_suspend;
+static int ftraced_stop;
+
+static int ftrace_record_suspend;
+
+static struct dyn_ftrace *ftrace_free_records;
+
+
+#ifdef CONFIG_KPROBES
+static inline void freeze_record(struct dyn_ftrace *rec)
+{
+ if (!(rec->flags & FTRACE_FL_FROZEN)) {
+ rec->flags |= FTRACE_FL_FROZEN;
+ frozen_record_count++;
+ }
+}
+
+static inline void unfreeze_record(struct dyn_ftrace *rec)
+{
+ if (rec->flags & FTRACE_FL_FROZEN) {
+ rec->flags &= ~FTRACE_FL_FROZEN;
+ frozen_record_count--;
+ }
+}
+
+static inline int record_frozen(struct dyn_ftrace *rec)
+{
+ return rec->flags & FTRACE_FL_FROZEN;
+}
+#else
+# define freeze_record(rec) ({ 0; })
+# define unfreeze_record(rec) ({ 0; })
+# define record_frozen(rec) ({ 0; })
+#endif /* CONFIG_KPROBES */
+
+int skip_trace(unsigned long ip)
+{
+ unsigned long fl;
+ struct dyn_ftrace *rec;
+ struct hlist_node *t;
+ struct hlist_head *head;
+
+ if (frozen_record_count == 0)
+ return 0;
+
+ head = &ftrace_hash[hash_long(ip, FTRACE_HASHBITS)];
+ hlist_for_each_entry_rcu(rec, t, head, node) {
+ if (rec->ip == ip) {
+ if (record_frozen(rec)) {
+ if (rec->flags & FTRACE_FL_FAILED)
+ return 1;
+
+ if (!(rec->flags & FTRACE_FL_CONVERTED))
+ return 1;
+
+ if (!tracing_on || !ftrace_enabled)
+ return 1;
+
+ if (ftrace_filtered) {
+ fl = rec->flags & (FTRACE_FL_FILTER |
+ FTRACE_FL_NOTRACE);
+ if (!fl || (fl & FTRACE_FL_NOTRACE))
+ return 1;
+ }
+ }
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static inline int
+ftrace_ip_in_hash(unsigned long ip, unsigned long key)
+{
+ struct dyn_ftrace *p;
+ struct hlist_node *t;
+ int found = 0;
+
+ hlist_for_each_entry_rcu(p, t, &ftrace_hash[key], node) {
+ if (p->ip == ip) {
+ found = 1;
+ break;
+ }
+ }
+
+ return found;
+}
+
+static inline void
+ftrace_add_hash(struct dyn_ftrace *node, unsigned long key)
+{
+ hlist_add_head_rcu(&node->node, &ftrace_hash[key]);
+}
+
+/* called from kstop_machine */
+static inline void ftrace_del_hash(struct dyn_ftrace *node)
+{
+ hlist_del(&node->node);
+}
+
+static void ftrace_free_rec(struct dyn_ftrace *rec)
+{
+ /* no locking, only called from kstop_machine */
+
+ rec->ip = (unsigned long)ftrace_free_records;
+ ftrace_free_records = rec;
+ rec->flags |= FTRACE_FL_FREE;
+}
+
+static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
+{
+ struct dyn_ftrace *rec;
+
+ /* First check for freed records */
+ if (ftrace_free_records) {
+ rec = ftrace_free_records;
+
+ if (unlikely(!(rec->flags & FTRACE_FL_FREE))) {
+ WARN_ON_ONCE(1);
+ ftrace_free_records = NULL;
+ ftrace_disabled = 1;
+ ftrace_enabled = 0;
+ return NULL;
+ }
+
+ ftrace_free_records = (void *)rec->ip;
+ memset(rec, 0, sizeof(*rec));
+ return rec;
+ }
+
+ if (ftrace_pages->index == ENTRIES_PER_PAGE) {
+ if (!ftrace_pages->next)
+ return NULL;
+ ftrace_pages = ftrace_pages->next;
+ }
+
+ return &ftrace_pages->records[ftrace_pages->index++];
+}
+
+static void
+ftrace_record_ip(unsigned long ip)
+{
+ struct dyn_ftrace *node;
+ unsigned long flags;
+ unsigned long key;
+ int resched;
+ int atomic;
+ int cpu;
+
+ if (!ftrace_enabled || ftrace_disabled)
+ return;
+
+ resched = need_resched();
+ preempt_disable_notrace();
+
+ /*
+ * We simply need to protect against recursion.
+ * Use the the raw version of smp_processor_id and not
+ * __get_cpu_var which can call debug hooks that can
+ * cause a recursive crash here.
+ */
+ cpu = raw_smp_processor_id();
+ per_cpu(ftrace_shutdown_disable_cpu, cpu)++;
+ if (per_cpu(ftrace_shutdown_disable_cpu, cpu) != 1)
+ goto out;
+
+ if (unlikely(ftrace_record_suspend))
+ goto out;
+
+ key = hash_long(ip, FTRACE_HASHBITS);
+
+ WARN_ON_ONCE(key >= FTRACE_HASHSIZE);
+
+ if (ftrace_ip_in_hash(ip, key))
+ goto out;
+
+ atomic = irqs_disabled();
+
+ spin_lock_irqsave(&ftrace_shutdown_lock, flags);
+
+ /* This ip may have hit the hash before the lock */
+ if (ftrace_ip_in_hash(ip, key))
+ goto out_unlock;
+
+ node = ftrace_alloc_dyn_node(ip);
+ if (!node)
+ goto out_unlock;
+
+ node->ip = ip;
+
+ ftrace_add_hash(node, key);
+
+ ftraced_trigger = 1;
+
+ out_unlock:
+ spin_unlock_irqrestore(&ftrace_shutdown_lock, flags);
+ out:
+ per_cpu(ftrace_shutdown_disable_cpu, cpu)--;
+
+ /* prevent recursion with scheduler */
+ if (resched)
+ preempt_enable_no_resched_notrace();
+ else
+ preempt_enable_notrace();
+}
+
+#define FTRACE_ADDR ((long)(ftrace_caller))
+
+static int
+__ftrace_replace_code(struct dyn_ftrace *rec,
+ unsigned char *old, unsigned char *new, int enable)
+{
+ unsigned long ip, fl;
+
+ ip = rec->ip;
+
+ if (ftrace_filtered && enable) {
+ /*
+ * If filtering is on:
+ *
+ * If this record is set to be filtered and
+ * is enabled then do nothing.
+ *
+ * If this record is set to be filtered and
+ * it is not enabled, enable it.
+ *
+ * If this record is not set to be filtered
+ * and it is not enabled do nothing.
+ *
+ * If this record is set not to trace then
+ * do nothing.
+ *
+ * If this record is set not to trace and
+ * it is enabled then disable it.
+ *
+ * If this record is not set to be filtered and
+ * it is enabled, disable it.
+ */
+
+ fl = rec->flags & (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE |
+ FTRACE_FL_ENABLED);
+
+ if ((fl == (FTRACE_FL_FILTER | FTRACE_FL_ENABLED)) ||
+ (fl == (FTRACE_FL_FILTER | FTRACE_FL_NOTRACE)) ||
+ !fl || (fl == FTRACE_FL_NOTRACE))
+ return 0;
+
+ /*
+ * If it is enabled disable it,
+ * otherwise enable it!
+ */
+ if (fl & FTRACE_FL_ENABLED) {
+ /* swap new and old */
+ new = old;
+ old = ftrace_call_replace(ip, FTRACE_ADDR);
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ } else {
+ new = ftrace_call_replace(ip, FTRACE_ADDR);
+ rec->flags |= FTRACE_FL_ENABLED;
+ }
+ } else {
+
+ if (enable) {
+ /*
+ * If this record is set not to trace and is
+ * not enabled, do nothing.
+ */
+ fl = rec->flags & (FTRACE_FL_NOTRACE | FTRACE_FL_ENABLED);
+ if (fl == FTRACE_FL_NOTRACE)
+ return 0;
+
+ new = ftrace_call_replace(ip, FTRACE_ADDR);
+ } else
+ old = ftrace_call_replace(ip, FTRACE_ADDR);
+
+ if (enable) {
+ if (rec->flags & FTRACE_FL_ENABLED)
+ return 0;
+ rec->flags |= FTRACE_FL_ENABLED;
+ } else {
+ if (!(rec->flags & FTRACE_FL_ENABLED))
+ return 0;
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ }
+ }
+
+ return ftrace_modify_code(ip, old, new);
+}
+
+static void ftrace_replace_code(int enable)
+{
+ int i, failed;
+ unsigned char *new = NULL, *old = NULL;
+ struct dyn_ftrace *rec;
+ struct ftrace_page *pg;
+
+ if (enable)
+ old = ftrace_nop_replace();
+ else
+ new = ftrace_nop_replace();
+
+ for (pg = ftrace_pages_start; pg; pg = pg->next) {
+ for (i = 0; i < pg->index; i++) {
+ rec = &pg->records[i];
+
+ /* don't modify code that has already faulted */
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+
+ /* ignore updates to this record's mcount site */
+ if (get_kprobe((void *)rec->ip)) {
+ freeze_record(rec);
+ continue;
+ } else {
+ unfreeze_record(rec);
+ }
+
+ failed = __ftrace_replace_code(rec, old, new, enable);
+ if (failed && (rec->flags & FTRACE_FL_CONVERTED)) {
+ rec->flags |= FTRACE_FL_FAILED;
+ if ((system_state == SYSTEM_BOOTING) ||
+ !core_kernel_text(rec->ip)) {
+ ftrace_del_hash(rec);
+ ftrace_free_rec(rec);
+ }
+ }
+ }
+ }
+}
+
+static void ftrace_shutdown_replenish(void)
+{
+ if (ftrace_pages->next)
+ return;
+
+ /* allocate another page */
+ ftrace_pages->next = (void *)get_zeroed_page(GFP_KERNEL);
+}
+
+static int
+ftrace_code_disable(struct dyn_ftrace *rec)
+{
+ unsigned long ip;
+ unsigned char *nop, *call;
+ int failed;
+
+ ip = rec->ip;
+
+ nop = ftrace_nop_replace();
+ call = ftrace_call_replace(ip, MCOUNT_ADDR);
+
+ failed = ftrace_modify_code(ip, call, nop);
+ if (failed) {
+ rec->flags |= FTRACE_FL_FAILED;
+ return 0;
+ }
+ return 1;
+}
+
+static int __ftrace_update_code(void *ignore);
+
+static int __ftrace_modify_code(void *data)
+{
+ unsigned long addr;
+ int *command = data;
+
+ if (*command & FTRACE_ENABLE_CALLS) {
+ /*
+ * Update any recorded ips now that we have the
+ * machine stopped
+ */
+ __ftrace_update_code(NULL);
+ ftrace_replace_code(1);
+ tracing_on = 1;
+ } else if (*command & FTRACE_DISABLE_CALLS) {
+ ftrace_replace_code(0);
+ tracing_on = 0;
+ }
+
+ if (*command & FTRACE_UPDATE_TRACE_FUNC)
+ ftrace_update_ftrace_func(ftrace_trace_function);
+
+ if (*command & FTRACE_ENABLE_MCOUNT) {
+ addr = (unsigned long)ftrace_record_ip;
+ ftrace_mcount_set(&addr);
+ } else if (*command & FTRACE_DISABLE_MCOUNT) {
+ addr = (unsigned long)ftrace_stub;
+ ftrace_mcount_set(&addr);
+ }
+
+ return 0;
+}
+
+static void ftrace_run_update_code(int command)
+{
+ stop_machine_run(__ftrace_modify_code, &command, NR_CPUS);
+}
+
+void ftrace_disable_daemon(void)
+{
+ /* Stop the daemon from calling kstop_machine */
+ mutex_lock(&ftraced_lock);
+ ftraced_stop = 1;
+ mutex_unlock(&ftraced_lock);
+
+ ftrace_force_update();
+}
+
+void ftrace_enable_daemon(void)
+{
+ mutex_lock(&ftraced_lock);
+ ftraced_stop = 0;
+ mutex_unlock(&ftraced_lock);
+
+ ftrace_force_update();
+}
+
+static ftrace_func_t saved_ftrace_func;
+
+static void ftrace_startup(void)
+{
+ int command = 0;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ mutex_lock(&ftraced_lock);
+ ftraced_suspend++;
+ if (ftraced_suspend == 1)
+ command |= FTRACE_ENABLE_CALLS;
+
+ if (saved_ftrace_func != ftrace_trace_function) {
+ saved_ftrace_func = ftrace_trace_function;
+ command |= FTRACE_UPDATE_TRACE_FUNC;
+ }
+
+ if (!command || !ftrace_enabled)
+ goto out;
+
+ ftrace_run_update_code(command);
+ out:
+ mutex_unlock(&ftraced_lock);
+}
+
+static void ftrace_shutdown(void)
+{
+ int command = 0;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ mutex_lock(&ftraced_lock);
+ ftraced_suspend--;
+ if (!ftraced_suspend)
+ command |= FTRACE_DISABLE_CALLS;
+
+ if (saved_ftrace_func != ftrace_trace_function) {
+ saved_ftrace_func = ftrace_trace_function;
+ command |= FTRACE_UPDATE_TRACE_FUNC;
+ }
+
+ if (!command || !ftrace_enabled)
+ goto out;
+
+ ftrace_run_update_code(command);
+ out:
+ mutex_unlock(&ftraced_lock);
+}
+
+static void ftrace_startup_sysctl(void)
+{
+ int command = FTRACE_ENABLE_MCOUNT;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ mutex_lock(&ftraced_lock);
+ /* Force update next time */
+ saved_ftrace_func = NULL;
+ /* ftraced_suspend is true if we want ftrace running */
+ if (ftraced_suspend)
+ command |= FTRACE_ENABLE_CALLS;
+
+ ftrace_run_update_code(command);
+ mutex_unlock(&ftraced_lock);
+}
+
+static void ftrace_shutdown_sysctl(void)
+{
+ int command = FTRACE_DISABLE_MCOUNT;
+
+ if (unlikely(ftrace_disabled))
+ return;
+
+ mutex_lock(&ftraced_lock);
+ /* ftraced_suspend is true if ftrace is running */
+ if (ftraced_suspend)
+ command |= FTRACE_DISABLE_CALLS;
+
+ ftrace_run_update_code(command);
+ mutex_unlock(&ftraced_lock);
+}
+
+static cycle_t ftrace_update_time;
+static unsigned long ftrace_update_cnt;
+unsigned long ftrace_update_tot_cnt;
+
+static int __ftrace_update_code(void *ignore)
+{
+ int i, save_ftrace_enabled;
+ cycle_t start, stop;
+ struct dyn_ftrace *p;
+ struct hlist_node *t, *n;
+ struct hlist_head *head, temp_list;
+
+ /* Don't be recording funcs now */
+ ftrace_record_suspend++;
+ save_ftrace_enabled = ftrace_enabled;
+ ftrace_enabled = 0;
+
+ start = ftrace_now(raw_smp_processor_id());
+ ftrace_update_cnt = 0;
+
+ /* No locks needed, the machine is stopped! */
+ for (i = 0; i < FTRACE_HASHSIZE; i++) {
+ INIT_HLIST_HEAD(&temp_list);
+ head = &ftrace_hash[i];
+
+ /* all CPUS are stopped, we are safe to modify code */
+ hlist_for_each_entry_safe(p, t, n, head, node) {
+ /* Skip over failed records which have not been
+ * freed. */
+ if (p->flags & FTRACE_FL_FAILED)
+ continue;
+
+ /* Unconverted records are always at the head of the
+ * hash bucket. Once we encounter a converted record,
+ * simply skip over to the next bucket. Saves ftraced
+ * some processor cycles (ftrace does its bid for
+ * global warming :-p ). */
+ if (p->flags & (FTRACE_FL_CONVERTED))
+ break;
+
+ /* Ignore updates to this record's mcount site.
+ * Reintroduce this record at the head of this
+ * bucket to attempt to "convert" it again if
+ * the kprobe on it is unregistered before the
+ * next run. */
+ if (get_kprobe((void *)p->ip)) {
+ ftrace_del_hash(p);
+ INIT_HLIST_NODE(&p->node);
+ hlist_add_head(&p->node, &temp_list);
+ freeze_record(p);
+ continue;
+ } else {
+ unfreeze_record(p);
+ }
+
+ /* convert record (i.e, patch mcount-call with NOP) */
+ if (ftrace_code_disable(p)) {
+ p->flags |= FTRACE_FL_CONVERTED;
+ ftrace_update_cnt++;
+ } else {
+ if ((system_state == SYSTEM_BOOTING) ||
+ !core_kernel_text(p->ip)) {
+ ftrace_del_hash(p);
+ ftrace_free_rec(p);
+ }
+ }
+ }
+
+ hlist_for_each_entry_safe(p, t, n, &temp_list, node) {
+ hlist_del(&p->node);
+ INIT_HLIST_NODE(&p->node);
+ hlist_add_head(&p->node, head);
+ }
+ }
+
+ stop = ftrace_now(raw_smp_processor_id());
+ ftrace_update_time = stop - start;
+ ftrace_update_tot_cnt += ftrace_update_cnt;
+ ftraced_trigger = 0;
+
+ ftrace_enabled = save_ftrace_enabled;
+ ftrace_record_suspend--;
+
+ return 0;
+}
+
+static int ftrace_update_code(void)
+{
+ if (unlikely(ftrace_disabled) ||
+ !ftrace_enabled || !ftraced_trigger)
+ return 0;
+
+ stop_machine_run(__ftrace_update_code, NULL, NR_CPUS);
+
+ return 1;
+}
+
+static int ftraced(void *ignore)
+{
+ unsigned long usecs;
+
+ while (!kthread_should_stop()) {
+
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ /* check once a second */
+ schedule_timeout(HZ);
+
+ if (unlikely(ftrace_disabled))
+ continue;
+
+ mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftraced_lock);
+ if (!ftraced_suspend && !ftraced_stop &&
+ ftrace_update_code()) {
+ usecs = nsecs_to_usecs(ftrace_update_time);
+ if (ftrace_update_tot_cnt > 100000) {
+ ftrace_update_tot_cnt = 0;
+ pr_info("hm, dftrace overflow: %lu change%s"
+ " (%lu total) in %lu usec%s\n",
+ ftrace_update_cnt,
+ ftrace_update_cnt != 1 ? "s" : "",
+ ftrace_update_tot_cnt,
+ usecs, usecs != 1 ? "s" : "");
+ ftrace_disabled = 1;
+ WARN_ON_ONCE(1);
+ }
+ }
+ mutex_unlock(&ftraced_lock);
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ ftrace_shutdown_replenish();
+ }
+ __set_current_state(TASK_RUNNING);
+ return 0;
+}
+
+static int __init ftrace_dyn_table_alloc(void)
+{
+ struct ftrace_page *pg;
+ int cnt;
+ int i;
+
+ /* allocate a few pages */
+ ftrace_pages_start = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!ftrace_pages_start)
+ return -1;
+
+ /*
+ * Allocate a few more pages.
+ *
+ * TODO: have some parser search vmlinux before
+ * final linking to find all calls to ftrace.
+ * Then we can:
+ * a) know how many pages to allocate.
+ * and/or
+ * b) set up the table then.
+ *
+ * The dynamic code is still necessary for
+ * modules.
+ */
+
+ pg = ftrace_pages = ftrace_pages_start;
+
+ cnt = NR_TO_INIT / ENTRIES_PER_PAGE;
+
+ for (i = 0; i < cnt; i++) {
+ pg->next = (void *)get_zeroed_page(GFP_KERNEL);
+
+ /* If we fail, we'll try later anyway */
+ if (!pg->next)
+ break;
+
+ pg = pg->next;
+ }
+
+ return 0;
+}
+
+enum {
+ FTRACE_ITER_FILTER = (1 << 0),
+ FTRACE_ITER_CONT = (1 << 1),
+ FTRACE_ITER_NOTRACE = (1 << 2),
+ FTRACE_ITER_FAILURES = (1 << 3),
+};
+
+#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
+
+struct ftrace_iterator {
+ loff_t pos;
+ struct ftrace_page *pg;
+ unsigned idx;
+ unsigned flags;
+ unsigned char buffer[FTRACE_BUFF_MAX+1];
+ unsigned buffer_idx;
+ unsigned filtered;
+};
+
+static void *
+t_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ struct dyn_ftrace *rec = NULL;
+
+ (*pos)++;
+
+ retry:
+ if (iter->idx >= iter->pg->index) {
+ if (iter->pg->next) {
+ iter->pg = iter->pg->next;
+ iter->idx = 0;
+ goto retry;
+ }
+ } else {
+ rec = &iter->pg->records[iter->idx++];
+ if ((!(iter->flags & FTRACE_ITER_FAILURES) &&
+ (rec->flags & FTRACE_FL_FAILED)) ||
+
+ ((iter->flags & FTRACE_ITER_FAILURES) &&
+ (!(rec->flags & FTRACE_FL_FAILED) ||
+ (rec->flags & FTRACE_FL_FREE))) ||
+
+ ((iter->flags & FTRACE_ITER_FILTER) &&
+ !(rec->flags & FTRACE_FL_FILTER)) ||
+
+ ((iter->flags & FTRACE_ITER_NOTRACE) &&
+ !(rec->flags & FTRACE_FL_NOTRACE))) {
+ rec = NULL;
+ goto retry;
+ }
+ }
+
+ iter->pos = *pos;
+
+ return rec;
+}
+
+static void *t_start(struct seq_file *m, loff_t *pos)
+{
+ struct ftrace_iterator *iter = m->private;
+ void *p = NULL;
+ loff_t l = -1;
+
+ if (*pos != iter->pos) {
+ for (p = t_next(m, p, &l); p && l < *pos; p = t_next(m, p, &l))
+ ;
+ } else {
+ l = *pos;
+ p = t_next(m, p, &l);
+ }
+
+ return p;
+}
+
+static void t_stop(struct seq_file *m, void *p)
+{
+}
+
+static int t_show(struct seq_file *m, void *v)
+{
+ struct dyn_ftrace *rec = v;
+ char str[KSYM_SYMBOL_LEN];
+
+ if (!rec)
+ return 0;
+
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+
+ seq_printf(m, "%s\n", str);
+
+ return 0;
+}
+
+static struct seq_operations show_ftrace_seq_ops = {
+ .start = t_start,
+ .next = t_next,
+ .stop = t_stop,
+ .show = t_show,
+};
+
+static int
+ftrace_avail_open(struct inode *inode, struct file *file)
+{
+ struct ftrace_iterator *iter;
+ int ret;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ iter->pg = ftrace_pages_start;
+ iter->pos = -1;
+
+ ret = seq_open(file, &show_ftrace_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+
+ m->private = iter;
+ } else {
+ kfree(iter);
+ }
+
+ return ret;
+}
+
+int ftrace_avail_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = (struct seq_file *)file->private_data;
+ struct ftrace_iterator *iter = m->private;
+
+ seq_release(inode, file);
+ kfree(iter);
+
+ return 0;
+}
+
+static int
+ftrace_failures_open(struct inode *inode, struct file *file)
+{
+ int ret;
+ struct seq_file *m;
+ struct ftrace_iterator *iter;
+
+ ret = ftrace_avail_open(inode, file);
+ if (!ret) {
+ m = (struct seq_file *)file->private_data;
+ iter = (struct ftrace_iterator *)m->private;
+ iter->flags = FTRACE_ITER_FAILURES;
+ }
+
+ return ret;
+}
+
+
+static void ftrace_filter_reset(int enable)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ unsigned long type = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+ unsigned i;
+
+ /* keep kstop machine from running */
+ preempt_disable();
+ if (enable)
+ ftrace_filtered = 0;
+ pg = ftrace_pages_start;
+ while (pg) {
+ for (i = 0; i < pg->index; i++) {
+ rec = &pg->records[i];
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+ rec->flags &= ~type;
+ }
+ pg = pg->next;
+ }
+ preempt_enable();
+}
+
+static int
+ftrace_regex_open(struct inode *inode, struct file *file, int enable)
+{
+ struct ftrace_iterator *iter;
+ int ret = 0;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ mutex_lock(&ftrace_regex_lock);
+ if ((file->f_mode & FMODE_WRITE) &&
+ !(file->f_flags & O_APPEND))
+ ftrace_filter_reset(enable);
+
+ if (file->f_mode & FMODE_READ) {
+ iter->pg = ftrace_pages_start;
+ iter->pos = -1;
+ iter->flags = enable ? FTRACE_ITER_FILTER :
+ FTRACE_ITER_NOTRACE;
+
+ ret = seq_open(file, &show_ftrace_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = iter;
+ } else
+ kfree(iter);
+ } else
+ file->private_data = iter;
+ mutex_unlock(&ftrace_regex_lock);
+
+ return ret;
+}
+
+static int
+ftrace_filter_open(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_open(inode, file, 1);
+}
+
+static int
+ftrace_notrace_open(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_open(inode, file, 0);
+}
+
+static ssize_t
+ftrace_regex_read(struct file *file, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ if (file->f_mode & FMODE_READ)
+ return seq_read(file, ubuf, cnt, ppos);
+ else
+ return -EPERM;
+}
+
+static loff_t
+ftrace_regex_lseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t ret;
+
+ if (file->f_mode & FMODE_READ)
+ ret = seq_lseek(file, offset, origin);
+ else
+ file->f_pos = ret = 1;
+
+ return ret;
+}
+
+enum {
+ MATCH_FULL,
+ MATCH_FRONT_ONLY,
+ MATCH_MIDDLE_ONLY,
+ MATCH_END_ONLY,
+};
+
+static void
+ftrace_match(unsigned char *buff, int len, int enable)
+{
+ char str[KSYM_SYMBOL_LEN];
+ char *search = NULL;
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec;
+ int type = MATCH_FULL;
+ unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+ unsigned i, match = 0, search_len = 0;
+
+ for (i = 0; i < len; i++) {
+ if (buff[i] == '*') {
+ if (!i) {
+ search = buff + i + 1;
+ type = MATCH_END_ONLY;
+ search_len = len - (i + 1);
+ } else {
+ if (type == MATCH_END_ONLY) {
+ type = MATCH_MIDDLE_ONLY;
+ } else {
+ match = i;
+ type = MATCH_FRONT_ONLY;
+ }
+ buff[i] = 0;
+ break;
+ }
+ }
+ }
+
+ /* keep kstop machine from running */
+ preempt_disable();
+ if (enable)
+ ftrace_filtered = 1;
+ pg = ftrace_pages_start;
+ while (pg) {
+ for (i = 0; i < pg->index; i++) {
+ int matched = 0;
+ char *ptr;
+
+ rec = &pg->records[i];
+ if (rec->flags & FTRACE_FL_FAILED)
+ continue;
+ kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
+ switch (type) {
+ case MATCH_FULL:
+ if (strcmp(str, buff) == 0)
+ matched = 1;
+ break;
+ case MATCH_FRONT_ONLY:
+ if (memcmp(str, buff, match) == 0)
+ matched = 1;
+ break;
+ case MATCH_MIDDLE_ONLY:
+ if (strstr(str, search))
+ matched = 1;
+ break;
+ case MATCH_END_ONLY:
+ ptr = strstr(str, search);
+ if (ptr && (ptr[search_len] == 0))
+ matched = 1;
+ break;
+ }
+ if (matched)
+ rec->flags |= flag;
+ }
+ pg = pg->next;
+ }
+ preempt_enable();
+}
+
+static ssize_t
+ftrace_regex_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos, int enable)
+{
+ struct ftrace_iterator *iter;
+ char ch;
+ size_t read = 0;
+ ssize_t ret;
+
+ if (!cnt || cnt < 0)
+ return 0;
+
+ mutex_lock(&ftrace_regex_lock);
+
+ if (file->f_mode & FMODE_READ) {
+ struct seq_file *m = file->private_data;
+ iter = m->private;
+ } else
+ iter = file->private_data;
+
+ if (!*ppos) {
+ iter->flags &= ~FTRACE_ITER_CONT;
+ iter->buffer_idx = 0;
+ }
+
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+
+ if (!(iter->flags & ~FTRACE_ITER_CONT)) {
+ /* skip white space */
+ while (cnt && isspace(ch)) {
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ if (isspace(ch)) {
+ file->f_pos += read;
+ ret = read;
+ goto out;
+ }
+
+ iter->buffer_idx = 0;
+ }
+
+ while (cnt && !isspace(ch)) {
+ if (iter->buffer_idx < FTRACE_BUFF_MAX)
+ iter->buffer[iter->buffer_idx++] = ch;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ if (isspace(ch)) {
+ iter->filtered++;
+ iter->buffer[iter->buffer_idx] = 0;
+ ftrace_match(iter->buffer, iter->buffer_idx, enable);
+ iter->buffer_idx = 0;
+ } else
+ iter->flags |= FTRACE_ITER_CONT;
+
+
+ file->f_pos += read;
+
+ ret = read;
+ out:
+ mutex_unlock(&ftrace_regex_lock);
+
+ return ret;
+}
+
+static ssize_t
+ftrace_filter_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return ftrace_regex_write(file, ubuf, cnt, ppos, 1);
+}
+
+static ssize_t
+ftrace_notrace_write(struct file *file, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return ftrace_regex_write(file, ubuf, cnt, ppos, 0);
+}
+
+static void
+ftrace_set_regex(unsigned char *buf, int len, int reset, int enable)
+{
+ if (unlikely(ftrace_disabled))
+ return;
+
+ mutex_lock(&ftrace_regex_lock);
+ if (reset)
+ ftrace_filter_reset(enable);
+ if (buf)
+ ftrace_match(buf, len, enable);
+ mutex_unlock(&ftrace_regex_lock);
+}
+
+/**
+ * ftrace_set_filter - set a function to filter on in ftrace
+ * @buf - the string that holds the function filter text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Filters denote which functions should be enabled when tracing is enabled.
+ * If @buf is NULL and reset is set, all functions will be enabled for tracing.
+ */
+void ftrace_set_filter(unsigned char *buf, int len, int reset)
+{
+ ftrace_set_regex(buf, len, reset, 1);
+}
+
+/**
+ * ftrace_set_notrace - set a function to not trace in ftrace
+ * @buf - the string that holds the function notrace text.
+ * @len - the length of the string.
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Notrace Filters denote which functions should not be enabled when tracing
+ * is enabled. If @buf is NULL and reset is set, all functions will be enabled
+ * for tracing.
+ */
+void ftrace_set_notrace(unsigned char *buf, int len, int reset)
+{
+ ftrace_set_regex(buf, len, reset, 0);
+}
+
+static int
+ftrace_regex_release(struct inode *inode, struct file *file, int enable)
+{
+ struct seq_file *m = (struct seq_file *)file->private_data;
+ struct ftrace_iterator *iter;
+
+ mutex_lock(&ftrace_regex_lock);
+ if (file->f_mode & FMODE_READ) {
+ iter = m->private;
+
+ seq_release(inode, file);
+ } else
+ iter = file->private_data;
+
+ if (iter->buffer_idx) {
+ iter->filtered++;
+ iter->buffer[iter->buffer_idx] = 0;
+ ftrace_match(iter->buffer, iter->buffer_idx, enable);
+ }
+
+ mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftraced_lock);
+ if (iter->filtered && ftraced_suspend && ftrace_enabled)
+ ftrace_run_update_code(FTRACE_ENABLE_CALLS);
+ mutex_unlock(&ftraced_lock);
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ kfree(iter);
+ mutex_unlock(&ftrace_regex_lock);
+ return 0;
+}
+
+static int
+ftrace_filter_release(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_release(inode, file, 1);
+}
+
+static int
+ftrace_notrace_release(struct inode *inode, struct file *file)
+{
+ return ftrace_regex_release(inode, file, 0);
+}
+
+static ssize_t
+ftraced_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ /* don't worry about races */
+ char *buf = ftraced_stop ? "disabled\n" : "enabled\n";
+ int r = strlen(buf);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+ftraced_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ if (strncmp(buf, "enable", 6) == 0)
+ val = 1;
+ else if (strncmp(buf, "disable", 7) == 0)
+ val = 0;
+ else {
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ val = !!val;
+ }
+
+ if (val)
+ ftrace_enable_daemon();
+ else
+ ftrace_disable_daemon();
+
+ filp->f_pos += cnt;
+
+ return cnt;
+}
+
+static struct file_operations ftrace_avail_fops = {
+ .open = ftrace_avail_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = ftrace_avail_release,
+};
+
+static struct file_operations ftrace_failures_fops = {
+ .open = ftrace_failures_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = ftrace_avail_release,
+};
+
+static struct file_operations ftrace_filter_fops = {
+ .open = ftrace_filter_open,
+ .read = ftrace_regex_read,
+ .write = ftrace_filter_write,
+ .llseek = ftrace_regex_lseek,
+ .release = ftrace_filter_release,
+};
+
+static struct file_operations ftrace_notrace_fops = {
+ .open = ftrace_notrace_open,
+ .read = ftrace_regex_read,
+ .write = ftrace_notrace_write,
+ .llseek = ftrace_regex_lseek,
+ .release = ftrace_notrace_release,
+};
+
+static struct file_operations ftraced_fops = {
+ .open = tracing_open_generic,
+ .read = ftraced_read,
+ .write = ftraced_write,
+};
+
+/**
+ * ftrace_force_update - force an update to all recording ftrace functions
+ */
+int ftrace_force_update(void)
+{
+ int ret = 0;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ mutex_lock(&ftrace_sysctl_lock);
+ mutex_lock(&ftraced_lock);
+
+ /*
+ * If ftraced_trigger is not set, then there is nothing
+ * to update.
+ */
+ if (ftraced_trigger && !ftrace_update_code())
+ ret = -EBUSY;
+
+ mutex_unlock(&ftraced_lock);
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ return ret;
+}
+
+static void ftrace_force_shutdown(void)
+{
+ struct task_struct *task;
+ int command = FTRACE_DISABLE_CALLS | FTRACE_UPDATE_TRACE_FUNC;
+
+ mutex_lock(&ftraced_lock);
+ task = ftraced_task;
+ ftraced_task = NULL;
+ ftraced_suspend = -1;
+ ftrace_run_update_code(command);
+ mutex_unlock(&ftraced_lock);
+
+ if (task)
+ kthread_stop(task);
+}
+
+static __init int ftrace_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ d_tracer = tracing_init_dentry();
+
+ entry = debugfs_create_file("available_filter_functions", 0444,
+ d_tracer, NULL, &ftrace_avail_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'available_filter_functions' entry\n");
+
+ entry = debugfs_create_file("failures", 0444,
+ d_tracer, NULL, &ftrace_failures_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'failures' entry\n");
+
+ entry = debugfs_create_file("set_ftrace_filter", 0644, d_tracer,
+ NULL, &ftrace_filter_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_ftrace_filter' entry\n");
+
+ entry = debugfs_create_file("set_ftrace_notrace", 0644, d_tracer,
+ NULL, &ftrace_notrace_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'set_ftrace_notrace' entry\n");
+
+ entry = debugfs_create_file("ftraced_enabled", 0644, d_tracer,
+ NULL, &ftraced_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'ftraced_enabled' entry\n");
+ return 0;
+}
+
+fs_initcall(ftrace_init_debugfs);
+
+static int __init ftrace_dynamic_init(void)
+{
+ struct task_struct *p;
+ unsigned long addr;
+ int ret;
+
+ addr = (unsigned long)ftrace_record_ip;
+
+ stop_machine_run(ftrace_dyn_arch_init, &addr, NR_CPUS);
+
+ /* ftrace_dyn_arch_init places the return code in addr */
+ if (addr) {
+ ret = (int)addr;
+ goto failed;
+ }
+
+ ret = ftrace_dyn_table_alloc();
+ if (ret)
+ goto failed;
+
+ p = kthread_run(ftraced, NULL, "ftraced");
+ if (IS_ERR(p)) {
+ ret = -1;
+ goto failed;
+ }
+
+ last_ftrace_enabled = ftrace_enabled = 1;
+ ftraced_task = p;
+
+ return 0;
+
+ failed:
+ ftrace_disabled = 1;
+ return ret;
+}
+
+core_initcall(ftrace_dynamic_init);
+#else
+# define ftrace_startup() do { } while (0)
+# define ftrace_shutdown() do { } while (0)
+# define ftrace_startup_sysctl() do { } while (0)
+# define ftrace_shutdown_sysctl() do { } while (0)
+# define ftrace_force_shutdown() do { } while (0)
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
+/**
+ * ftrace_kill_atomic - kill ftrace from critical sections
+ *
+ * This function should be used by panic code. It stops ftrace
+ * but in a not so nice way. If you need to simply kill ftrace
+ * from a non-atomic section, use ftrace_kill.
+ */
+void ftrace_kill_atomic(void)
+{
+ ftrace_disabled = 1;
+ ftrace_enabled = 0;
+#ifdef CONFIG_DYNAMIC_FTRACE
+ ftraced_suspend = -1;
+#endif
+ clear_ftrace_function();
+}
+
+/**
+ * ftrace_kill - totally shutdown ftrace
+ *
+ * This is a safety measure. If something was detected that seems
+ * wrong, calling this function will keep ftrace from doing
+ * any more modifications, and updates.
+ * used when something went wrong.
+ */
+void ftrace_kill(void)
+{
+ mutex_lock(&ftrace_sysctl_lock);
+ ftrace_disabled = 1;
+ ftrace_enabled = 0;
+
+ clear_ftrace_function();
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ /* Try to totally disable ftrace */
+ ftrace_force_shutdown();
+}
+
+/**
+ * register_ftrace_function - register a function for profiling
+ * @ops - ops structure that holds the function for profiling.
+ *
+ * Register a function to be called by all functions in the
+ * kernel.
+ *
+ * Note: @ops->func and all the functions it calls must be labeled
+ * with "notrace", otherwise it will go into a
+ * recursive loop.
+ */
+int register_ftrace_function(struct ftrace_ops *ops)
+{
+ int ret;
+
+ if (unlikely(ftrace_disabled))
+ return -1;
+
+ mutex_lock(&ftrace_sysctl_lock);
+ ret = __register_ftrace_function(ops);
+ ftrace_startup();
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ return ret;
+}
+
+/**
+ * unregister_ftrace_function - unresgister a function for profiling.
+ * @ops - ops structure that holds the function to unregister
+ *
+ * Unregister a function that was added to be called by ftrace profiling.
+ */
+int unregister_ftrace_function(struct ftrace_ops *ops)
+{
+ int ret;
+
+ mutex_lock(&ftrace_sysctl_lock);
+ ret = __unregister_ftrace_function(ops);
+ ftrace_shutdown();
+ mutex_unlock(&ftrace_sysctl_lock);
+
+ return ret;
+}
+
+int
+ftrace_enable_sysctl(struct ctl_table *table, int write,
+ struct file *file, void __user *buffer, size_t *lenp,
+ loff_t *ppos)
+{
+ int ret;
+
+ if (unlikely(ftrace_disabled))
+ return -ENODEV;
+
+ mutex_lock(&ftrace_sysctl_lock);
+
+ ret = proc_dointvec(table, write, file, buffer, lenp, ppos);
+
+ if (ret || !write || (last_ftrace_enabled == ftrace_enabled))
+ goto out;
+
+ last_ftrace_enabled = ftrace_enabled;
+
+ if (ftrace_enabled) {
+
+ ftrace_startup_sysctl();
+
+ /* we are starting ftrace again */
+ if (ftrace_list != &ftrace_list_end) {
+ if (ftrace_list->next == &ftrace_list_end)
+ ftrace_trace_function = ftrace_list->func;
+ else
+ ftrace_trace_function = ftrace_list_func;
+ }
+
+ } else {
+ /* stopping ftrace calls (just send to ftrace_stub) */
+ ftrace_trace_function = ftrace_stub;
+
+ ftrace_shutdown_sysctl();
+ }
+
+ out:
+ mutex_unlock(&ftrace_sysctl_lock);
+ return ret;
+}
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
new file mode 100644
index 00000000000..868e121c8e3
--- /dev/null
+++ b/kernel/trace/trace.c
@@ -0,0 +1,3161 @@
+/*
+ * ring buffer based function tracer
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ * Originally taken from the RT patch by:
+ * Arnaldo Carvalho de Melo <acme@redhat.com>
+ *
+ * Based on code from the latency_tracer, that is:
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 William Lee Irwin III
+ */
+#include <linux/utsrelease.h>
+#include <linux/kallsyms.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/pagemap.h>
+#include <linux/hardirq.h>
+#include <linux/linkage.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/module.h>
+#include <linux/percpu.h>
+#include <linux/ctype.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/gfp.h>
+#include <linux/fs.h>
+#include <linux/kprobes.h>
+#include <linux/writeback.h>
+
+#include <linux/stacktrace.h>
+
+#include "trace.h"
+
+unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX;
+unsigned long __read_mostly tracing_thresh;
+
+static unsigned long __read_mostly tracing_nr_buffers;
+static cpumask_t __read_mostly tracing_buffer_mask;
+
+#define for_each_tracing_cpu(cpu) \
+ for_each_cpu_mask(cpu, tracing_buffer_mask)
+
+static int trace_alloc_page(void);
+static int trace_free_page(void);
+
+static int tracing_disabled = 1;
+
+static unsigned long tracing_pages_allocated;
+
+long
+ns2usecs(cycle_t nsec)
+{
+ nsec += 500;
+ do_div(nsec, 1000);
+ return nsec;
+}
+
+cycle_t ftrace_now(int cpu)
+{
+ return cpu_clock(cpu);
+}
+
+/*
+ * The global_trace is the descriptor that holds the tracing
+ * buffers for the live tracing. For each CPU, it contains
+ * a link list of pages that will store trace entries. The
+ * page descriptor of the pages in the memory is used to hold
+ * the link list by linking the lru item in the page descriptor
+ * to each of the pages in the buffer per CPU.
+ *
+ * For each active CPU there is a data field that holds the
+ * pages for the buffer for that CPU. Each CPU has the same number
+ * of pages allocated for its buffer.
+ */
+static struct trace_array global_trace;
+
+static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu);
+
+/*
+ * The max_tr is used to snapshot the global_trace when a maximum
+ * latency is reached. Some tracers will use this to store a maximum
+ * trace while it continues examining live traces.
+ *
+ * The buffers for the max_tr are set up the same as the global_trace.
+ * When a snapshot is taken, the link list of the max_tr is swapped
+ * with the link list of the global_trace and the buffers are reset for
+ * the global_trace so the tracing can continue.
+ */
+static struct trace_array max_tr;
+
+static DEFINE_PER_CPU(struct trace_array_cpu, max_data);
+
+/* tracer_enabled is used to toggle activation of a tracer */
+static int tracer_enabled = 1;
+
+/* function tracing enabled */
+int ftrace_function_enabled;
+
+/*
+ * trace_nr_entries is the number of entries that is allocated
+ * for a buffer. Note, the number of entries is always rounded
+ * to ENTRIES_PER_PAGE.
+ */
+static unsigned long trace_nr_entries = 65536UL;
+
+/* trace_types holds a link list of available tracers. */
+static struct tracer *trace_types __read_mostly;
+
+/* current_trace points to the tracer that is currently active */
+static struct tracer *current_trace __read_mostly;
+
+/*
+ * max_tracer_type_len is used to simplify the allocating of
+ * buffers to read userspace tracer names. We keep track of
+ * the longest tracer name registered.
+ */
+static int max_tracer_type_len;
+
+/*
+ * trace_types_lock is used to protect the trace_types list.
+ * This lock is also used to keep user access serialized.
+ * Accesses from userspace will grab this lock while userspace
+ * activities happen inside the kernel.
+ */
+static DEFINE_MUTEX(trace_types_lock);
+
+/* trace_wait is a waitqueue for tasks blocked on trace_poll */
+static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
+
+/* trace_flags holds iter_ctrl options */
+unsigned long trace_flags = TRACE_ITER_PRINT_PARENT;
+
+static notrace void no_trace_init(struct trace_array *tr)
+{
+ int cpu;
+
+ ftrace_function_enabled = 0;
+ if(tr->ctrl)
+ for_each_online_cpu(cpu)
+ tracing_reset(tr->data[cpu]);
+ tracer_enabled = 0;
+}
+
+/* dummy trace to disable tracing */
+static struct tracer no_tracer __read_mostly = {
+ .name = "none",
+ .init = no_trace_init
+};
+
+
+/**
+ * trace_wake_up - wake up tasks waiting for trace input
+ *
+ * Simply wakes up any task that is blocked on the trace_wait
+ * queue. These is used with trace_poll for tasks polling the trace.
+ */
+void trace_wake_up(void)
+{
+ /*
+ * The runqueue_is_locked() can fail, but this is the best we
+ * have for now:
+ */
+ if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked())
+ wake_up(&trace_wait);
+}
+
+#define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry))
+
+static int __init set_nr_entries(char *str)
+{
+ unsigned long nr_entries;
+ int ret;
+
+ if (!str)
+ return 0;
+ ret = strict_strtoul(str, 0, &nr_entries);
+ /* nr_entries can not be zero */
+ if (ret < 0 || nr_entries == 0)
+ return 0;
+ trace_nr_entries = nr_entries;
+ return 1;
+}
+__setup("trace_entries=", set_nr_entries);
+
+unsigned long nsecs_to_usecs(unsigned long nsecs)
+{
+ return nsecs / 1000;
+}
+
+/*
+ * trace_flag_type is an enumeration that holds different
+ * states when a trace occurs. These are:
+ * IRQS_OFF - interrupts were disabled
+ * NEED_RESCED - reschedule is requested
+ * HARDIRQ - inside an interrupt handler
+ * SOFTIRQ - inside a softirq handler
+ */
+enum trace_flag_type {
+ TRACE_FLAG_IRQS_OFF = 0x01,
+ TRACE_FLAG_NEED_RESCHED = 0x02,
+ TRACE_FLAG_HARDIRQ = 0x04,
+ TRACE_FLAG_SOFTIRQ = 0x08,
+};
+
+/*
+ * TRACE_ITER_SYM_MASK masks the options in trace_flags that
+ * control the output of kernel symbols.
+ */
+#define TRACE_ITER_SYM_MASK \
+ (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
+
+/* These must match the bit postions in trace_iterator_flags */
+static const char *trace_options[] = {
+ "print-parent",
+ "sym-offset",
+ "sym-addr",
+ "verbose",
+ "raw",
+ "hex",
+ "bin",
+ "block",
+ "stacktrace",
+ "sched-tree",
+ NULL
+};
+
+/*
+ * ftrace_max_lock is used to protect the swapping of buffers
+ * when taking a max snapshot. The buffers themselves are
+ * protected by per_cpu spinlocks. But the action of the swap
+ * needs its own lock.
+ *
+ * This is defined as a raw_spinlock_t in order to help
+ * with performance when lockdep debugging is enabled.
+ */
+static raw_spinlock_t ftrace_max_lock =
+ (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+
+/*
+ * Copy the new maximum trace into the separate maximum-trace
+ * structure. (this way the maximum trace is permanently saved,
+ * for later retrieval via /debugfs/tracing/latency_trace)
+ */
+static void
+__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
+{
+ struct trace_array_cpu *data = tr->data[cpu];
+
+ max_tr.cpu = cpu;
+ max_tr.time_start = data->preempt_timestamp;
+
+ data = max_tr.data[cpu];
+ data->saved_latency = tracing_max_latency;
+
+ memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
+ data->pid = tsk->pid;
+ data->uid = tsk->uid;
+ data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
+ data->policy = tsk->policy;
+ data->rt_priority = tsk->rt_priority;
+
+ /* record this tasks comm */
+ tracing_record_cmdline(current);
+}
+
+#define CHECK_COND(cond) \
+ if (unlikely(cond)) { \
+ tracing_disabled = 1; \
+ WARN_ON(1); \
+ return -1; \
+ }
+
+/**
+ * check_pages - integrity check of trace buffers
+ *
+ * As a safty measure we check to make sure the data pages have not
+ * been corrupted.
+ */
+int check_pages(struct trace_array_cpu *data)
+{
+ struct page *page, *tmp;
+
+ CHECK_COND(data->trace_pages.next->prev != &data->trace_pages);
+ CHECK_COND(data->trace_pages.prev->next != &data->trace_pages);
+
+ list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) {
+ CHECK_COND(page->lru.next->prev != &page->lru);
+ CHECK_COND(page->lru.prev->next != &page->lru);
+ }
+
+ return 0;
+}
+
+/**
+ * head_page - page address of the first page in per_cpu buffer.
+ *
+ * head_page returns the page address of the first page in
+ * a per_cpu buffer. This also preforms various consistency
+ * checks to make sure the buffer has not been corrupted.
+ */
+void *head_page(struct trace_array_cpu *data)
+{
+ struct page *page;
+
+ if (list_empty(&data->trace_pages))
+ return NULL;
+
+ page = list_entry(data->trace_pages.next, struct page, lru);
+ BUG_ON(&page->lru == &data->trace_pages);
+
+ return page_address(page);
+}
+
+/**
+ * trace_seq_printf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ va_list ap;
+ int ret;
+
+ if (!len)
+ return 0;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
+ va_end(ap);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len)
+ return 0;
+
+ s->len += ret;
+
+ return len;
+}
+
+/**
+ * trace_seq_puts - trace sequence printing of simple string
+ * @s: trace sequence descriptor
+ * @str: simple string to record
+ *
+ * The tracer may use either the sequence operations or its own
+ * copy to user routines. This function records a simple string
+ * into a special buffer (@s) for later retrieval by a sequencer
+ * or other mechanism.
+ */
+static int
+trace_seq_puts(struct trace_seq *s, const char *str)
+{
+ int len = strlen(str);
+
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return 0;
+
+ memcpy(s->buffer + s->len, str, len);
+ s->len += len;
+
+ return len;
+}
+
+static int
+trace_seq_putc(struct trace_seq *s, unsigned char c)
+{
+ if (s->len >= (PAGE_SIZE - 1))
+ return 0;
+
+ s->buffer[s->len++] = c;
+
+ return 1;
+}
+
+static int
+trace_seq_putmem(struct trace_seq *s, void *mem, size_t len)
+{
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return 0;
+
+ memcpy(s->buffer + s->len, mem, len);
+ s->len += len;
+
+ return len;
+}
+
+#define HEX_CHARS 17
+static const char hex2asc[] = "0123456789abcdef";
+
+static int
+trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
+{
+ unsigned char hex[HEX_CHARS];
+ unsigned char *data = mem;
+ unsigned char byte;
+ int i, j;
+
+ BUG_ON(len >= HEX_CHARS);
+
+#ifdef __BIG_ENDIAN
+ for (i = 0, j = 0; i < len; i++) {
+#else
+ for (i = len-1, j = 0; i >= 0; i--) {
+#endif
+ byte = data[i];
+
+ hex[j++] = hex2asc[byte & 0x0f];
+ hex[j++] = hex2asc[byte >> 4];
+ }
+ hex[j++] = ' ';
+
+ return trace_seq_putmem(s, hex, j);
+}
+
+static void
+trace_seq_reset(struct trace_seq *s)
+{
+ s->len = 0;
+ s->readpos = 0;
+}
+
+ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
+{
+ int len;
+ int ret;
+
+ if (s->len <= s->readpos)
+ return -EBUSY;
+
+ len = s->len - s->readpos;
+ if (cnt > len)
+ cnt = len;
+ ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
+ if (ret)
+ return -EFAULT;
+
+ s->readpos += len;
+ return cnt;
+}
+
+static void
+trace_print_seq(struct seq_file *m, struct trace_seq *s)
+{
+ int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+
+ s->buffer[len] = 0;
+ seq_puts(m, s->buffer);
+
+ trace_seq_reset(s);
+}
+
+/*
+ * flip the trace buffers between two trace descriptors.
+ * This usually is the buffers between the global_trace and
+ * the max_tr to record a snapshot of a current trace.
+ *
+ * The ftrace_max_lock must be held.
+ */
+static void
+flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2)
+{
+ struct list_head flip_pages;
+
+ INIT_LIST_HEAD(&flip_pages);
+
+ memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx,
+ sizeof(struct trace_array_cpu) -
+ offsetof(struct trace_array_cpu, trace_head_idx));
+
+ check_pages(tr1);
+ check_pages(tr2);
+ list_splice_init(&tr1->trace_pages, &flip_pages);
+ list_splice_init(&tr2->trace_pages, &tr1->trace_pages);
+ list_splice_init(&flip_pages, &tr2->trace_pages);
+ BUG_ON(!list_empty(&flip_pages));
+ check_pages(tr1);
+ check_pages(tr2);
+}
+
+/**
+ * update_max_tr - snapshot all trace buffers from global_trace to max_tr
+ * @tr: tracer
+ * @tsk: the task with the latency
+ * @cpu: The cpu that initiated the trace.
+ *
+ * Flip the buffers between the @tr and the max_tr and record information
+ * about which task was the cause of this latency.
+ */
+void
+update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
+{
+ struct trace_array_cpu *data;
+ int i;
+
+ WARN_ON_ONCE(!irqs_disabled());
+ __raw_spin_lock(&ftrace_max_lock);
+ /* clear out all the previous traces */
+ for_each_tracing_cpu(i) {
+ data = tr->data[i];
+ flip_trace(max_tr.data[i], data);
+ tracing_reset(data);
+ }
+
+ __update_max_tr(tr, tsk, cpu);
+ __raw_spin_unlock(&ftrace_max_lock);
+}
+
+/**
+ * update_max_tr_single - only copy one trace over, and reset the rest
+ * @tr - tracer
+ * @tsk - task with the latency
+ * @cpu - the cpu of the buffer to copy.
+ *
+ * Flip the trace of a single CPU buffer between the @tr and the max_tr.
+ */
+void
+update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
+{
+ struct trace_array_cpu *data = tr->data[cpu];
+ int i;
+
+ WARN_ON_ONCE(!irqs_disabled());
+ __raw_spin_lock(&ftrace_max_lock);
+ for_each_tracing_cpu(i)
+ tracing_reset(max_tr.data[i]);
+
+ flip_trace(max_tr.data[cpu], data);
+ tracing_reset(data);
+
+ __update_max_tr(tr, tsk, cpu);
+ __raw_spin_unlock(&ftrace_max_lock);
+}
+
+/**
+ * register_tracer - register a tracer with the ftrace system.
+ * @type - the plugin for the tracer
+ *
+ * Register a new plugin tracer.
+ */
+int register_tracer(struct tracer *type)
+{
+ struct tracer *t;
+ int len;
+ int ret = 0;
+
+ if (!type->name) {
+ pr_info("Tracer must have a name\n");
+ return -1;
+ }
+
+ mutex_lock(&trace_types_lock);
+ for (t = trace_types; t; t = t->next) {
+ if (strcmp(type->name, t->name) == 0) {
+ /* already found */
+ pr_info("Trace %s already registered\n",
+ type->name);
+ ret = -1;
+ goto out;
+ }
+ }
+
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+ if (type->selftest) {
+ struct tracer *saved_tracer = current_trace;
+ struct trace_array_cpu *data;
+ struct trace_array *tr = &global_trace;
+ int saved_ctrl = tr->ctrl;
+ int i;
+ /*
+ * Run a selftest on this tracer.
+ * Here we reset the trace buffer, and set the current
+ * tracer to be this tracer. The tracer can then run some
+ * internal tracing to verify that everything is in order.
+ * If we fail, we do not register this tracer.
+ */
+ for_each_tracing_cpu(i) {
+ data = tr->data[i];
+ if (!head_page(data))
+ continue;
+ tracing_reset(data);
+ }
+ current_trace = type;
+ tr->ctrl = 0;
+ /* the test is responsible for initializing and enabling */
+ pr_info("Testing tracer %s: ", type->name);
+ ret = type->selftest(type, tr);
+ /* the test is responsible for resetting too */
+ current_trace = saved_tracer;
+ tr->ctrl = saved_ctrl;
+ if (ret) {
+ printk(KERN_CONT "FAILED!\n");
+ goto out;
+ }
+ /* Only reset on passing, to avoid touching corrupted buffers */
+ for_each_tracing_cpu(i) {
+ data = tr->data[i];
+ if (!head_page(data))
+ continue;
+ tracing_reset(data);
+ }
+ printk(KERN_CONT "PASSED\n");
+ }
+#endif
+
+ type->next = trace_types;
+ trace_types = type;
+ len = strlen(type->name);
+ if (len > max_tracer_type_len)
+ max_tracer_type_len = len;
+
+ out:
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+}
+
+void unregister_tracer(struct tracer *type)
+{
+ struct tracer **t;
+ int len;
+
+ mutex_lock(&trace_types_lock);
+ for (t = &trace_types; *t; t = &(*t)->next) {
+ if (*t == type)
+ goto found;
+ }
+ pr_info("Trace %s not registered\n", type->name);
+ goto out;
+
+ found:
+ *t = (*t)->next;
+ if (strlen(type->name) != max_tracer_type_len)
+ goto out;
+
+ max_tracer_type_len = 0;
+ for (t = &trace_types; *t; t = &(*t)->next) {
+ len = strlen((*t)->name);
+ if (len > max_tracer_type_len)
+ max_tracer_type_len = len;
+ }
+ out:
+ mutex_unlock(&trace_types_lock);
+}
+
+void tracing_reset(struct trace_array_cpu *data)
+{
+ data->trace_idx = 0;
+ data->overrun = 0;
+ data->trace_head = data->trace_tail = head_page(data);
+ data->trace_head_idx = 0;
+ data->trace_tail_idx = 0;
+}
+
+#define SAVED_CMDLINES 128
+static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
+static unsigned map_cmdline_to_pid[SAVED_CMDLINES];
+static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN];
+static int cmdline_idx;
+static DEFINE_SPINLOCK(trace_cmdline_lock);
+
+/* temporary disable recording */
+atomic_t trace_record_cmdline_disabled __read_mostly;
+
+static void trace_init_cmdlines(void)
+{
+ memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline));
+ memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid));
+ cmdline_idx = 0;
+}
+
+void trace_stop_cmdline_recording(void);
+
+static void trace_save_cmdline(struct task_struct *tsk)
+{
+ unsigned map;
+ unsigned idx;
+
+ if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT))
+ return;
+
+ /*
+ * It's not the end of the world if we don't get
+ * the lock, but we also don't want to spin
+ * nor do we want to disable interrupts,
+ * so if we miss here, then better luck next time.
+ */
+ if (!spin_trylock(&trace_cmdline_lock))
+ return;
+
+ idx = map_pid_to_cmdline[tsk->pid];
+ if (idx >= SAVED_CMDLINES) {
+ idx = (cmdline_idx + 1) % SAVED_CMDLINES;
+
+ map = map_cmdline_to_pid[idx];
+ if (map <= PID_MAX_DEFAULT)
+ map_pid_to_cmdline[map] = (unsigned)-1;
+
+ map_pid_to_cmdline[tsk->pid] = idx;
+
+ cmdline_idx = idx;
+ }
+
+ memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN);
+
+ spin_unlock(&trace_cmdline_lock);
+}
+
+static char *trace_find_cmdline(int pid)
+{
+ char *cmdline = "<...>";
+ unsigned map;
+
+ if (!pid)
+ return "<idle>";
+
+ if (pid > PID_MAX_DEFAULT)
+ goto out;
+
+ map = map_pid_to_cmdline[pid];
+ if (map >= SAVED_CMDLINES)
+ goto out;
+
+ cmdline = saved_cmdlines[map];
+
+ out:
+ return cmdline;
+}
+
+void tracing_record_cmdline(struct task_struct *tsk)
+{
+ if (atomic_read(&trace_record_cmdline_disabled))
+ return;
+
+ trace_save_cmdline(tsk);
+}
+
+static inline struct list_head *
+trace_next_list(struct trace_array_cpu *data, struct list_head *next)
+{
+ /*
+ * Roundrobin - but skip the head (which is not a real page):
+ */
+ next = next->next;
+ if (unlikely(next == &data->trace_pages))
+ next = next->next;
+ BUG_ON(next == &data->trace_pages);
+
+ return next;
+}
+
+static inline void *
+trace_next_page(struct trace_array_cpu *data, void *addr)
+{
+ struct list_head *next;
+ struct page *page;
+
+ page = virt_to_page(addr);
+
+ next = trace_next_list(data, &page->lru);
+ page = list_entry(next, struct page, lru);
+
+ return page_address(page);
+}
+
+static inline struct trace_entry *
+tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data)
+{
+ unsigned long idx, idx_next;
+ struct trace_entry *entry;
+
+ data->trace_idx++;
+ idx = data->trace_head_idx;
+ idx_next = idx + 1;
+
+ BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE);
+
+ entry = data->trace_head + idx * TRACE_ENTRY_SIZE;
+
+ if (unlikely(idx_next >= ENTRIES_PER_PAGE)) {
+ data->trace_head = trace_next_page(data, data->trace_head);
+ idx_next = 0;
+ }
+
+ if (data->trace_head == data->trace_tail &&
+ idx_next == data->trace_tail_idx) {
+ /* overrun */
+ data->overrun++;
+ data->trace_tail_idx++;
+ if (data->trace_tail_idx >= ENTRIES_PER_PAGE) {
+ data->trace_tail =
+ trace_next_page(data, data->trace_tail);
+ data->trace_tail_idx = 0;
+ }
+ }
+
+ data->trace_head_idx = idx_next;
+
+ return entry;
+}
+
+static inline void
+tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags)
+{
+ struct task_struct *tsk = current;
+ unsigned long pc;
+
+ pc = preempt_count();
+
+ entry->preempt_count = pc & 0xff;
+ entry->pid = (tsk) ? tsk->pid : 0;
+ entry->t = ftrace_now(raw_smp_processor_id());
+ entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
+ ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) |
+ ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
+ (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
+}
+
+void
+trace_function(struct trace_array *tr, struct trace_array_cpu *data,
+ unsigned long ip, unsigned long parent_ip, unsigned long flags)
+{
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&data->lock);
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, flags);
+ entry->type = TRACE_FN;
+ entry->fn.ip = ip;
+ entry->fn.parent_ip = parent_ip;
+ __raw_spin_unlock(&data->lock);
+ raw_local_irq_restore(irq_flags);
+}
+
+void
+ftrace(struct trace_array *tr, struct trace_array_cpu *data,
+ unsigned long ip, unsigned long parent_ip, unsigned long flags)
+{
+ if (likely(!atomic_read(&data->disabled)))
+ trace_function(tr, data, ip, parent_ip, flags);
+}
+
+#ifdef CONFIG_MMIOTRACE
+void __trace_mmiotrace_rw(struct trace_array *tr, struct trace_array_cpu *data,
+ struct mmiotrace_rw *rw)
+{
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&data->lock);
+
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, 0);
+ entry->type = TRACE_MMIO_RW;
+ entry->mmiorw = *rw;
+
+ __raw_spin_unlock(&data->lock);
+ raw_local_irq_restore(irq_flags);
+
+ trace_wake_up();
+}
+
+void __trace_mmiotrace_map(struct trace_array *tr, struct trace_array_cpu *data,
+ struct mmiotrace_map *map)
+{
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&data->lock);
+
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, 0);
+ entry->type = TRACE_MMIO_MAP;
+ entry->mmiomap = *map;
+
+ __raw_spin_unlock(&data->lock);
+ raw_local_irq_restore(irq_flags);
+
+ trace_wake_up();
+}
+#endif
+
+void __trace_stack(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long flags,
+ int skip)
+{
+ struct trace_entry *entry;
+ struct stack_trace trace;
+
+ if (!(trace_flags & TRACE_ITER_STACKTRACE))
+ return;
+
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, flags);
+ entry->type = TRACE_STACK;
+
+ memset(&entry->stack, 0, sizeof(entry->stack));
+
+ trace.nr_entries = 0;
+ trace.max_entries = FTRACE_STACK_ENTRIES;
+ trace.skip = skip;
+ trace.entries = entry->stack.caller;
+
+ save_stack_trace(&trace);
+}
+
+void
+__trace_special(void *__tr, void *__data,
+ unsigned long arg1, unsigned long arg2, unsigned long arg3)
+{
+ struct trace_array_cpu *data = __data;
+ struct trace_array *tr = __tr;
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&data->lock);
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, 0);
+ entry->type = TRACE_SPECIAL;
+ entry->special.arg1 = arg1;
+ entry->special.arg2 = arg2;
+ entry->special.arg3 = arg3;
+ __trace_stack(tr, data, irq_flags, 4);
+ __raw_spin_unlock(&data->lock);
+ raw_local_irq_restore(irq_flags);
+
+ trace_wake_up();
+}
+
+void
+tracing_sched_switch_trace(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned long flags)
+{
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&data->lock);
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, flags);
+ entry->type = TRACE_CTX;
+ entry->ctx.prev_pid = prev->pid;
+ entry->ctx.prev_prio = prev->prio;
+ entry->ctx.prev_state = prev->state;
+ entry->ctx.next_pid = next->pid;
+ entry->ctx.next_prio = next->prio;
+ entry->ctx.next_state = next->state;
+ __trace_stack(tr, data, flags, 5);
+ __raw_spin_unlock(&data->lock);
+ raw_local_irq_restore(irq_flags);
+}
+
+void
+tracing_sched_wakeup_trace(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct task_struct *wakee,
+ struct task_struct *curr,
+ unsigned long flags)
+{
+ struct trace_entry *entry;
+ unsigned long irq_flags;
+
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&data->lock);
+ entry = tracing_get_trace_entry(tr, data);
+ tracing_generic_entry_update(entry, flags);
+ entry->type = TRACE_WAKE;
+ entry->ctx.prev_pid = curr->pid;
+ entry->ctx.prev_prio = curr->prio;
+ entry->ctx.prev_state = curr->state;
+ entry->ctx.next_pid = wakee->pid;
+ entry->ctx.next_prio = wakee->prio;
+ entry->ctx.next_state = wakee->state;
+ __trace_stack(tr, data, flags, 6);
+ __raw_spin_unlock(&data->lock);
+ raw_local_irq_restore(irq_flags);
+
+ trace_wake_up();
+}
+
+void
+ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ if (tracing_disabled || current_trace == &no_tracer || !tr->ctrl)
+ return;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1))
+ __trace_special(tr, data, arg1, arg2, arg3);
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
+#ifdef CONFIG_FTRACE
+static void
+function_trace_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ if (unlikely(!ftrace_function_enabled))
+ return;
+
+ if (skip_trace(ip))
+ return;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1))
+ trace_function(tr, data, ip, parent_ip, flags);
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
+static struct ftrace_ops trace_ops __read_mostly =
+{
+ .func = function_trace_call,
+};
+
+void tracing_start_function_trace(void)
+{
+ ftrace_function_enabled = 0;
+ register_ftrace_function(&trace_ops);
+ if (tracer_enabled)
+ ftrace_function_enabled = 1;
+}
+
+void tracing_stop_function_trace(void)
+{
+ ftrace_function_enabled = 0;
+ unregister_ftrace_function(&trace_ops);
+}
+#endif
+
+enum trace_file_type {
+ TRACE_FILE_LAT_FMT = 1,
+};
+
+static struct trace_entry *
+trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data,
+ struct trace_iterator *iter, int cpu)
+{
+ struct page *page;
+ struct trace_entry *array;
+
+ if (iter->next_idx[cpu] >= tr->entries ||
+ iter->next_idx[cpu] >= data->trace_idx ||
+ (data->trace_head == data->trace_tail &&
+ data->trace_head_idx == data->trace_tail_idx))
+ return NULL;
+
+ if (!iter->next_page[cpu]) {
+ /* Initialize the iterator for this cpu trace buffer */
+ WARN_ON(!data->trace_tail);
+ page = virt_to_page(data->trace_tail);
+ iter->next_page[cpu] = &page->lru;
+ iter->next_page_idx[cpu] = data->trace_tail_idx;
+ }
+
+ page = list_entry(iter->next_page[cpu], struct page, lru);
+ BUG_ON(&data->trace_pages == &page->lru);
+
+ array = page_address(page);
+
+ WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE);
+ return &array[iter->next_page_idx[cpu]];
+}
+
+static struct trace_entry *
+find_next_entry(struct trace_iterator *iter, int *ent_cpu)
+{
+ struct trace_array *tr = iter->tr;
+ struct trace_entry *ent, *next = NULL;
+ int next_cpu = -1;
+ int cpu;
+
+ for_each_tracing_cpu(cpu) {
+ if (!head_page(tr->data[cpu]))
+ continue;
+ ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu);
+ /*
+ * Pick the entry with the smallest timestamp:
+ */
+ if (ent && (!next || ent->t < next->t)) {
+ next = ent;
+ next_cpu = cpu;
+ }
+ }
+
+ if (ent_cpu)
+ *ent_cpu = next_cpu;
+
+ return next;
+}
+
+static void trace_iterator_increment(struct trace_iterator *iter)
+{
+ iter->idx++;
+ iter->next_idx[iter->cpu]++;
+ iter->next_page_idx[iter->cpu]++;
+
+ if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) {
+ struct trace_array_cpu *data = iter->tr->data[iter->cpu];
+
+ iter->next_page_idx[iter->cpu] = 0;
+ iter->next_page[iter->cpu] =
+ trace_next_list(data, iter->next_page[iter->cpu]);
+ }
+}
+
+static void trace_consume(struct trace_iterator *iter)
+{
+ struct trace_array_cpu *data = iter->tr->data[iter->cpu];
+
+ data->trace_tail_idx++;
+ if (data->trace_tail_idx >= ENTRIES_PER_PAGE) {
+ data->trace_tail = trace_next_page(data, data->trace_tail);
+ data->trace_tail_idx = 0;
+ }
+
+ /* Check if we empty it, then reset the index */
+ if (data->trace_head == data->trace_tail &&
+ data->trace_head_idx == data->trace_tail_idx)
+ data->trace_idx = 0;
+}
+
+static void *find_next_entry_inc(struct trace_iterator *iter)
+{
+ struct trace_entry *next;
+ int next_cpu = -1;
+
+ next = find_next_entry(iter, &next_cpu);
+
+ iter->prev_ent = iter->ent;
+ iter->prev_cpu = iter->cpu;
+
+ iter->ent = next;
+ iter->cpu = next_cpu;
+
+ if (next)
+ trace_iterator_increment(iter);
+
+ return next ? iter : NULL;
+}
+
+static void *s_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct trace_iterator *iter = m->private;
+ void *last_ent = iter->ent;
+ int i = (int)*pos;
+ void *ent;
+
+ (*pos)++;
+
+ /* can't go backwards */
+ if (iter->idx > i)
+ return NULL;
+
+ if (iter->idx < 0)
+ ent = find_next_entry_inc(iter);
+ else
+ ent = iter;
+
+ while (ent && iter->idx < i)
+ ent = find_next_entry_inc(iter);
+
+ iter->pos = *pos;
+
+ if (last_ent && !ent)
+ seq_puts(m, "\n\nvim:ft=help\n");
+
+ return ent;
+}
+
+static void *s_start(struct seq_file *m, loff_t *pos)
+{
+ struct trace_iterator *iter = m->private;
+ void *p = NULL;
+ loff_t l = 0;
+ int i;
+
+ mutex_lock(&trace_types_lock);
+
+ if (!current_trace || current_trace != iter->trace) {
+ mutex_unlock(&trace_types_lock);
+ return NULL;
+ }
+
+ atomic_inc(&trace_record_cmdline_disabled);
+
+ /* let the tracer grab locks here if needed */
+ if (current_trace->start)
+ current_trace->start(iter);
+
+ if (*pos != iter->pos) {
+ iter->ent = NULL;
+ iter->cpu = 0;
+ iter->idx = -1;
+ iter->prev_ent = NULL;
+ iter->prev_cpu = -1;
+
+ for_each_tracing_cpu(i) {
+ iter->next_idx[i] = 0;
+ iter->next_page[i] = NULL;
+ }
+
+ for (p = iter; p && l < *pos; p = s_next(m, p, &l))
+ ;
+
+ } else {
+ l = *pos - 1;
+ p = s_next(m, p, &l);
+ }
+
+ return p;
+}
+
+static void s_stop(struct seq_file *m, void *p)
+{
+ struct trace_iterator *iter = m->private;
+
+ atomic_dec(&trace_record_cmdline_disabled);
+
+ /* let the tracer release locks here if needed */
+ if (current_trace && current_trace == iter->trace && iter->trace->stop)
+ iter->trace->stop(iter);
+
+ mutex_unlock(&trace_types_lock);
+}
+
+#define KRETPROBE_MSG "[unknown/kretprobe'd]"
+
+#ifdef CONFIG_KRETPROBES
+static inline int kretprobed(unsigned long addr)
+{
+ return addr == (unsigned long)kretprobe_trampoline;
+}
+#else
+static inline int kretprobed(unsigned long addr)
+{
+ return 0;
+}
+#endif /* CONFIG_KRETPROBES */
+
+static int
+seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
+{
+#ifdef CONFIG_KALLSYMS
+ char str[KSYM_SYMBOL_LEN];
+
+ kallsyms_lookup(address, NULL, NULL, NULL, str);
+
+ return trace_seq_printf(s, fmt, str);
+#endif
+ return 1;
+}
+
+static int
+seq_print_sym_offset(struct trace_seq *s, const char *fmt,
+ unsigned long address)
+{
+#ifdef CONFIG_KALLSYMS
+ char str[KSYM_SYMBOL_LEN];
+
+ sprint_symbol(str, address);
+ return trace_seq_printf(s, fmt, str);
+#endif
+ return 1;
+}
+
+#ifndef CONFIG_64BIT
+# define IP_FMT "%08lx"
+#else
+# define IP_FMT "%016lx"
+#endif
+
+static int
+seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
+{
+ int ret;
+
+ if (!ip)
+ return trace_seq_printf(s, "0");
+
+ if (sym_flags & TRACE_ITER_SYM_OFFSET)
+ ret = seq_print_sym_offset(s, "%s", ip);
+ else
+ ret = seq_print_sym_short(s, "%s", ip);
+
+ if (!ret)
+ return 0;
+
+ if (sym_flags & TRACE_ITER_SYM_ADDR)
+ ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
+ return ret;
+}
+
+static void print_lat_help_header(struct seq_file *m)
+{
+ seq_puts(m, "# _------=> CPU# \n");
+ seq_puts(m, "# / _-----=> irqs-off \n");
+ seq_puts(m, "# | / _----=> need-resched \n");
+ seq_puts(m, "# || / _---=> hardirq/softirq \n");
+ seq_puts(m, "# ||| / _--=> preempt-depth \n");
+ seq_puts(m, "# |||| / \n");
+ seq_puts(m, "# ||||| delay \n");
+ seq_puts(m, "# cmd pid ||||| time | caller \n");
+ seq_puts(m, "# \\ / ||||| \\ | / \n");
+}
+
+static void print_func_help_header(struct seq_file *m)
+{
+ seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n");
+ seq_puts(m, "# | | | | |\n");
+}
+
+
+static void
+print_trace_header(struct seq_file *m, struct trace_iterator *iter)
+{
+ unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
+ struct trace_array *tr = iter->tr;
+ struct trace_array_cpu *data = tr->data[tr->cpu];
+ struct tracer *type = current_trace;
+ unsigned long total = 0;
+ unsigned long entries = 0;
+ int cpu;
+ const char *name = "preemption";
+
+ if (type)
+ name = type->name;
+
+ for_each_tracing_cpu(cpu) {
+ if (head_page(tr->data[cpu])) {
+ total += tr->data[cpu]->trace_idx;
+ if (tr->data[cpu]->trace_idx > tr->entries)
+ entries += tr->entries;
+ else
+ entries += tr->data[cpu]->trace_idx;
+ }
+ }
+
+ seq_printf(m, "%s latency trace v1.1.5 on %s\n",
+ name, UTS_RELEASE);
+ seq_puts(m, "-----------------------------------"
+ "---------------------------------\n");
+ seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |"
+ " (M:%s VP:%d, KP:%d, SP:%d HP:%d",
+ nsecs_to_usecs(data->saved_latency),
+ entries,
+ total,
+ tr->cpu,
+#if defined(CONFIG_PREEMPT_NONE)
+ "server",
+#elif defined(CONFIG_PREEMPT_VOLUNTARY)
+ "desktop",
+#elif defined(CONFIG_PREEMPT)
+ "preempt",
+#else
+ "unknown",
+#endif
+ /* These are reserved for later use */
+ 0, 0, 0, 0);
+#ifdef CONFIG_SMP
+ seq_printf(m, " #P:%d)\n", num_online_cpus());
+#else
+ seq_puts(m, ")\n");
+#endif
+ seq_puts(m, " -----------------\n");
+ seq_printf(m, " | task: %.16s-%d "
+ "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n",
+ data->comm, data->pid, data->uid, data->nice,
+ data->policy, data->rt_priority);
+ seq_puts(m, " -----------------\n");
+
+ if (data->critical_start) {
+ seq_puts(m, " => started at: ");
+ seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags);
+ trace_print_seq(m, &iter->seq);
+ seq_puts(m, "\n => ended at: ");
+ seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
+ trace_print_seq(m, &iter->seq);
+ seq_puts(m, "\n");
+ }
+
+ seq_puts(m, "\n");
+}
+
+static void
+lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+{
+ int hardirq, softirq;
+ char *comm;
+
+ comm = trace_find_cmdline(entry->pid);
+
+ trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid);
+ trace_seq_printf(s, "%d", cpu);
+ trace_seq_printf(s, "%c%c",
+ (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.',
+ ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.'));
+
+ hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
+ softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
+ if (hardirq && softirq) {
+ trace_seq_putc(s, 'H');
+ } else {
+ if (hardirq) {
+ trace_seq_putc(s, 'h');
+ } else {
+ if (softirq)
+ trace_seq_putc(s, 's');
+ else
+ trace_seq_putc(s, '.');
+ }
+ }
+
+ if (entry->preempt_count)
+ trace_seq_printf(s, "%x", entry->preempt_count);
+ else
+ trace_seq_puts(s, ".");
+}
+
+unsigned long preempt_mark_thresh = 100;
+
+static void
+lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs,
+ unsigned long rel_usecs)
+{
+ trace_seq_printf(s, " %4lldus", abs_usecs);
+ if (rel_usecs > preempt_mark_thresh)
+ trace_seq_puts(s, "!: ");
+ else if (rel_usecs > 1)
+ trace_seq_puts(s, "+: ");
+ else
+ trace_seq_puts(s, " : ");
+}
+
+static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
+
+static int
+print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
+{
+ struct trace_seq *s = &iter->seq;
+ unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
+ struct trace_entry *next_entry = find_next_entry(iter, NULL);
+ unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
+ struct trace_entry *entry = iter->ent;
+ unsigned long abs_usecs;
+ unsigned long rel_usecs;
+ char *comm;
+ int S, T;
+ int i;
+ unsigned state;
+
+ if (!next_entry)
+ next_entry = entry;
+ rel_usecs = ns2usecs(next_entry->t - entry->t);
+ abs_usecs = ns2usecs(entry->t - iter->tr->time_start);
+
+ if (verbose) {
+ comm = trace_find_cmdline(entry->pid);
+ trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]"
+ " %ld.%03ldms (+%ld.%03ldms): ",
+ comm,
+ entry->pid, cpu, entry->flags,
+ entry->preempt_count, trace_idx,
+ ns2usecs(entry->t),
+ abs_usecs/1000,
+ abs_usecs % 1000, rel_usecs/1000,
+ rel_usecs % 1000);
+ } else {
+ lat_print_generic(s, entry, cpu);
+ lat_print_timestamp(s, abs_usecs, rel_usecs);
+ }
+ switch (entry->type) {
+ case TRACE_FN:
+ seq_print_ip_sym(s, entry->fn.ip, sym_flags);
+ trace_seq_puts(s, " (");
+ if (kretprobed(entry->fn.parent_ip))
+ trace_seq_puts(s, KRETPROBE_MSG);
+ else
+ seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags);
+ trace_seq_puts(s, ")\n");
+ break;
+ case TRACE_CTX:
+ case TRACE_WAKE:
+ T = entry->ctx.next_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.next_state] : 'X';
+
+ state = entry->ctx.prev_state ? __ffs(entry->ctx.prev_state) + 1 : 0;
+ S = state < sizeof(state_to_char) - 1 ? state_to_char[state] : 'X';
+ comm = trace_find_cmdline(entry->ctx.next_pid);
+ trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c %s\n",
+ entry->ctx.prev_pid,
+ entry->ctx.prev_prio,
+ S, entry->type == TRACE_CTX ? "==>" : " +",
+ entry->ctx.next_pid,
+ entry->ctx.next_prio,
+ T, comm);
+ break;
+ case TRACE_SPECIAL:
+ trace_seq_printf(s, "# %ld %ld %ld\n",
+ entry->special.arg1,
+ entry->special.arg2,
+ entry->special.arg3);
+ break;
+ case TRACE_STACK:
+ for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
+ if (i)
+ trace_seq_puts(s, " <= ");
+ seq_print_ip_sym(s, entry->stack.caller[i], sym_flags);
+ }
+ trace_seq_puts(s, "\n");
+ break;
+ default:
+ trace_seq_printf(s, "Unknown type %d\n", entry->type);
+ }
+ return 1;
+}
+
+static int print_trace_fmt(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
+ struct trace_entry *entry;
+ unsigned long usec_rem;
+ unsigned long long t;
+ unsigned long secs;
+ char *comm;
+ int ret;
+ int S, T;
+ int i;
+
+ entry = iter->ent;
+
+ comm = trace_find_cmdline(iter->ent->pid);
+
+ t = ns2usecs(entry->t);
+ usec_rem = do_div(t, 1000000ULL);
+ secs = (unsigned long)t;
+
+ ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid);
+ if (!ret)
+ return 0;
+ ret = trace_seq_printf(s, "[%02d] ", iter->cpu);
+ if (!ret)
+ return 0;
+ ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem);
+ if (!ret)
+ return 0;
+
+ switch (entry->type) {
+ case TRACE_FN:
+ ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags);
+ if (!ret)
+ return 0;
+ if ((sym_flags & TRACE_ITER_PRINT_PARENT) &&
+ entry->fn.parent_ip) {
+ ret = trace_seq_printf(s, " <-");
+ if (!ret)
+ return 0;
+ if (kretprobed(entry->fn.parent_ip))
+ ret = trace_seq_puts(s, KRETPROBE_MSG);
+ else
+ ret = seq_print_ip_sym(s, entry->fn.parent_ip,
+ sym_flags);
+ if (!ret)
+ return 0;
+ }
+ ret = trace_seq_printf(s, "\n");
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_CTX:
+ case TRACE_WAKE:
+ S = entry->ctx.prev_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.prev_state] : 'X';
+ T = entry->ctx.next_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.next_state] : 'X';
+ ret = trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c\n",
+ entry->ctx.prev_pid,
+ entry->ctx.prev_prio,
+ S,
+ entry->type == TRACE_CTX ? "==>" : " +",
+ entry->ctx.next_pid,
+ entry->ctx.next_prio,
+ T);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_SPECIAL:
+ ret = trace_seq_printf(s, "# %ld %ld %ld\n",
+ entry->special.arg1,
+ entry->special.arg2,
+ entry->special.arg3);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_STACK:
+ for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
+ if (i) {
+ ret = trace_seq_puts(s, " <= ");
+ if (!ret)
+ return 0;
+ }
+ ret = seq_print_ip_sym(s, entry->stack.caller[i],
+ sym_flags);
+ if (!ret)
+ return 0;
+ }
+ ret = trace_seq_puts(s, "\n");
+ if (!ret)
+ return 0;
+ break;
+ }
+ return 1;
+}
+
+static int print_raw_fmt(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry;
+ int ret;
+ int S, T;
+
+ entry = iter->ent;
+
+ ret = trace_seq_printf(s, "%d %d %llu ",
+ entry->pid, iter->cpu, entry->t);
+ if (!ret)
+ return 0;
+
+ switch (entry->type) {
+ case TRACE_FN:
+ ret = trace_seq_printf(s, "%x %x\n",
+ entry->fn.ip, entry->fn.parent_ip);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_CTX:
+ case TRACE_WAKE:
+ S = entry->ctx.prev_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.prev_state] : 'X';
+ T = entry->ctx.next_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.next_state] : 'X';
+ if (entry->type == TRACE_WAKE)
+ S = '+';
+ ret = trace_seq_printf(s, "%d %d %c %d %d %c\n",
+ entry->ctx.prev_pid,
+ entry->ctx.prev_prio,
+ S,
+ entry->ctx.next_pid,
+ entry->ctx.next_prio,
+ T);
+ if (!ret)
+ return 0;
+ break;
+ case TRACE_SPECIAL:
+ case TRACE_STACK:
+ ret = trace_seq_printf(s, "# %ld %ld %ld\n",
+ entry->special.arg1,
+ entry->special.arg2,
+ entry->special.arg3);
+ if (!ret)
+ return 0;
+ break;
+ }
+ return 1;
+}
+
+#define SEQ_PUT_FIELD_RET(s, x) \
+do { \
+ if (!trace_seq_putmem(s, &(x), sizeof(x))) \
+ return 0; \
+} while (0)
+
+#define SEQ_PUT_HEX_FIELD_RET(s, x) \
+do { \
+ if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \
+ return 0; \
+} while (0)
+
+static int print_hex_fmt(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ unsigned char newline = '\n';
+ struct trace_entry *entry;
+ int S, T;
+
+ entry = iter->ent;
+
+ SEQ_PUT_HEX_FIELD_RET(s, entry->pid);
+ SEQ_PUT_HEX_FIELD_RET(s, iter->cpu);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->t);
+
+ switch (entry->type) {
+ case TRACE_FN:
+ SEQ_PUT_HEX_FIELD_RET(s, entry->fn.ip);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip);
+ break;
+ case TRACE_CTX:
+ case TRACE_WAKE:
+ S = entry->ctx.prev_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.prev_state] : 'X';
+ T = entry->ctx.next_state < sizeof(state_to_char) ?
+ state_to_char[entry->ctx.next_state] : 'X';
+ if (entry->type == TRACE_WAKE)
+ S = '+';
+ SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_pid);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_prio);
+ SEQ_PUT_HEX_FIELD_RET(s, S);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_pid);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_prio);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip);
+ SEQ_PUT_HEX_FIELD_RET(s, T);
+ break;
+ case TRACE_SPECIAL:
+ case TRACE_STACK:
+ SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg1);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg2);
+ SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg3);
+ break;
+ }
+ SEQ_PUT_FIELD_RET(s, newline);
+
+ return 1;
+}
+
+static int print_bin_fmt(struct trace_iterator *iter)
+{
+ struct trace_seq *s = &iter->seq;
+ struct trace_entry *entry;
+
+ entry = iter->ent;
+
+ SEQ_PUT_FIELD_RET(s, entry->pid);
+ SEQ_PUT_FIELD_RET(s, entry->cpu);
+ SEQ_PUT_FIELD_RET(s, entry->t);
+
+ switch (entry->type) {
+ case TRACE_FN:
+ SEQ_PUT_FIELD_RET(s, entry->fn.ip);
+ SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip);
+ break;
+ case TRACE_CTX:
+ SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio);
+ SEQ_PUT_FIELD_RET(s, entry->ctx.next_state);
+ break;
+ case TRACE_SPECIAL:
+ case TRACE_STACK:
+ SEQ_PUT_FIELD_RET(s, entry->special.arg1);
+ SEQ_PUT_FIELD_RET(s, entry->special.arg2);
+ SEQ_PUT_FIELD_RET(s, entry->special.arg3);
+ break;
+ }
+ return 1;
+}
+
+static int trace_empty(struct trace_iterator *iter)
+{
+ struct trace_array_cpu *data;
+ int cpu;
+
+ for_each_tracing_cpu(cpu) {
+ data = iter->tr->data[cpu];
+
+ if (head_page(data) && data->trace_idx &&
+ (data->trace_tail != data->trace_head ||
+ data->trace_tail_idx != data->trace_head_idx))
+ return 0;
+ }
+ return 1;
+}
+
+static int print_trace_line(struct trace_iterator *iter)
+{
+ if (iter->trace && iter->trace->print_line)
+ return iter->trace->print_line(iter);
+
+ if (trace_flags & TRACE_ITER_BIN)
+ return print_bin_fmt(iter);
+
+ if (trace_flags & TRACE_ITER_HEX)
+ return print_hex_fmt(iter);
+
+ if (trace_flags & TRACE_ITER_RAW)
+ return print_raw_fmt(iter);
+
+ if (iter->iter_flags & TRACE_FILE_LAT_FMT)
+ return print_lat_fmt(iter, iter->idx, iter->cpu);
+
+ return print_trace_fmt(iter);
+}
+
+static int s_show(struct seq_file *m, void *v)
+{
+ struct trace_iterator *iter = v;
+
+ if (iter->ent == NULL) {
+ if (iter->tr) {
+ seq_printf(m, "# tracer: %s\n", iter->trace->name);
+ seq_puts(m, "#\n");
+ }
+ if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
+ /* print nothing if the buffers are empty */
+ if (trace_empty(iter))
+ return 0;
+ print_trace_header(m, iter);
+ if (!(trace_flags & TRACE_ITER_VERBOSE))
+ print_lat_help_header(m);
+ } else {
+ if (!(trace_flags & TRACE_ITER_VERBOSE))
+ print_func_help_header(m);
+ }
+ } else {
+ print_trace_line(iter);
+ trace_print_seq(m, &iter->seq);
+ }
+
+ return 0;
+}
+
+static struct seq_operations tracer_seq_ops = {
+ .start = s_start,
+ .next = s_next,
+ .stop = s_stop,
+ .show = s_show,
+};
+
+static struct trace_iterator *
+__tracing_open(struct inode *inode, struct file *file, int *ret)
+{
+ struct trace_iterator *iter;
+
+ if (tracing_disabled) {
+ *ret = -ENODEV;
+ return NULL;
+ }
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter) {
+ *ret = -ENOMEM;
+ goto out;
+ }
+
+ mutex_lock(&trace_types_lock);
+ if (current_trace && current_trace->print_max)
+ iter->tr = &max_tr;
+ else
+ iter->tr = inode->i_private;
+ iter->trace = current_trace;
+ iter->pos = -1;
+
+ /* TODO stop tracer */
+ *ret = seq_open(file, &tracer_seq_ops);
+ if (!*ret) {
+ struct seq_file *m = file->private_data;
+ m->private = iter;
+
+ /* stop the trace while dumping */
+ if (iter->tr->ctrl) {
+ tracer_enabled = 0;
+ ftrace_function_enabled = 0;
+ }
+
+ if (iter->trace && iter->trace->open)
+ iter->trace->open(iter);
+ } else {
+ kfree(iter);
+ iter = NULL;
+ }
+ mutex_unlock(&trace_types_lock);
+
+ out:
+ return iter;
+}
+
+int tracing_open_generic(struct inode *inode, struct file *filp)
+{
+ if (tracing_disabled)
+ return -ENODEV;
+
+ filp->private_data = inode->i_private;
+ return 0;
+}
+
+int tracing_release(struct inode *inode, struct file *file)
+{
+ struct seq_file *m = (struct seq_file *)file->private_data;
+ struct trace_iterator *iter = m->private;
+
+ mutex_lock(&trace_types_lock);
+ if (iter->trace && iter->trace->close)
+ iter->trace->close(iter);
+
+ /* reenable tracing if it was previously enabled */
+ if (iter->tr->ctrl) {
+ tracer_enabled = 1;
+ /*
+ * It is safe to enable function tracing even if it
+ * isn't used
+ */
+ ftrace_function_enabled = 1;
+ }
+ mutex_unlock(&trace_types_lock);
+
+ seq_release(inode, file);
+ kfree(iter);
+ return 0;
+}
+
+static int tracing_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ __tracing_open(inode, file, &ret);
+
+ return ret;
+}
+
+static int tracing_lt_open(struct inode *inode, struct file *file)
+{
+ struct trace_iterator *iter;
+ int ret;
+
+ iter = __tracing_open(inode, file, &ret);
+
+ if (!ret)
+ iter->iter_flags |= TRACE_FILE_LAT_FMT;
+
+ return ret;
+}
+
+
+static void *
+t_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct tracer *t = m->private;
+
+ (*pos)++;
+
+ if (t)
+ t = t->next;
+
+ m->private = t;
+
+ return t;
+}
+
+static void *t_start(struct seq_file *m, loff_t *pos)
+{
+ struct tracer *t = m->private;
+ loff_t l = 0;
+
+ mutex_lock(&trace_types_lock);
+ for (; t && l < *pos; t = t_next(m, t, &l))
+ ;
+
+ return t;
+}
+
+static void t_stop(struct seq_file *m, void *p)
+{
+ mutex_unlock(&trace_types_lock);
+}
+
+static int t_show(struct seq_file *m, void *v)
+{
+ struct tracer *t = v;
+
+ if (!t)
+ return 0;
+
+ seq_printf(m, "%s", t->name);
+ if (t->next)
+ seq_putc(m, ' ');
+ else
+ seq_putc(m, '\n');
+
+ return 0;
+}
+
+static struct seq_operations show_traces_seq_ops = {
+ .start = t_start,
+ .next = t_next,
+ .stop = t_stop,
+ .show = t_show,
+};
+
+static int show_traces_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ if (tracing_disabled)
+ return -ENODEV;
+
+ ret = seq_open(file, &show_traces_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = trace_types;
+ }
+
+ return ret;
+}
+
+static struct file_operations tracing_fops = {
+ .open = tracing_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = tracing_release,
+};
+
+static struct file_operations tracing_lt_fops = {
+ .open = tracing_lt_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = tracing_release,
+};
+
+static struct file_operations show_traces_fops = {
+ .open = show_traces_open,
+ .read = seq_read,
+ .release = seq_release,
+};
+
+/*
+ * Only trace on a CPU if the bitmask is set:
+ */
+static cpumask_t tracing_cpumask = CPU_MASK_ALL;
+
+/*
+ * When tracing/tracing_cpu_mask is modified then this holds
+ * the new bitmask we are about to install:
+ */
+static cpumask_t tracing_cpumask_new;
+
+/*
+ * The tracer itself will not take this lock, but still we want
+ * to provide a consistent cpumask to user-space:
+ */
+static DEFINE_MUTEX(tracing_cpumask_update_lock);
+
+/*
+ * Temporary storage for the character representation of the
+ * CPU bitmask (and one more byte for the newline):
+ */
+static char mask_str[NR_CPUS + 1];
+
+static ssize_t
+tracing_cpumask_read(struct file *filp, char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ int len;
+
+ mutex_lock(&tracing_cpumask_update_lock);
+
+ len = cpumask_scnprintf(mask_str, count, tracing_cpumask);
+ if (count - len < 2) {
+ count = -EINVAL;
+ goto out_err;
+ }
+ len += sprintf(mask_str + len, "\n");
+ count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1);
+
+out_err:
+ mutex_unlock(&tracing_cpumask_update_lock);
+
+ return count;
+}
+
+static ssize_t
+tracing_cpumask_write(struct file *filp, const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ int err, cpu;
+
+ mutex_lock(&tracing_cpumask_update_lock);
+ err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
+ if (err)
+ goto err_unlock;
+
+ raw_local_irq_disable();
+ __raw_spin_lock(&ftrace_max_lock);
+ for_each_tracing_cpu(cpu) {
+ /*
+ * Increase/decrease the disabled counter if we are
+ * about to flip a bit in the cpumask:
+ */
+ if (cpu_isset(cpu, tracing_cpumask) &&
+ !cpu_isset(cpu, tracing_cpumask_new)) {
+ atomic_inc(&global_trace.data[cpu]->disabled);
+ }
+ if (!cpu_isset(cpu, tracing_cpumask) &&
+ cpu_isset(cpu, tracing_cpumask_new)) {
+ atomic_dec(&global_trace.data[cpu]->disabled);
+ }
+ }
+ __raw_spin_unlock(&ftrace_max_lock);
+ raw_local_irq_enable();
+
+ tracing_cpumask = tracing_cpumask_new;
+
+ mutex_unlock(&tracing_cpumask_update_lock);
+
+ return count;
+
+err_unlock:
+ mutex_unlock(&tracing_cpumask_update_lock);
+
+ return err;
+}
+
+static struct file_operations tracing_cpumask_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_cpumask_read,
+ .write = tracing_cpumask_write,
+};
+
+static ssize_t
+tracing_iter_ctrl_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char *buf;
+ int r = 0;
+ int len = 0;
+ int i;
+
+ /* calulate max size */
+ for (i = 0; trace_options[i]; i++) {
+ len += strlen(trace_options[i]);
+ len += 3; /* "no" and space */
+ }
+
+ /* +2 for \n and \0 */
+ buf = kmalloc(len + 2, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ for (i = 0; trace_options[i]; i++) {
+ if (trace_flags & (1 << i))
+ r += sprintf(buf + r, "%s ", trace_options[i]);
+ else
+ r += sprintf(buf + r, "no%s ", trace_options[i]);
+ }
+
+ r += sprintf(buf + r, "\n");
+ WARN_ON(r >= len + 2);
+
+ r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+
+ kfree(buf);
+
+ return r;
+}
+
+static ssize_t
+tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ char *cmp = buf;
+ int neg = 0;
+ int i;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ if (strncmp(buf, "no", 2) == 0) {
+ neg = 1;
+ cmp += 2;
+ }
+
+ for (i = 0; trace_options[i]; i++) {
+ int len = strlen(trace_options[i]);
+
+ if (strncmp(cmp, trace_options[i], len) == 0) {
+ if (neg)
+ trace_flags &= ~(1 << i);
+ else
+ trace_flags |= (1 << i);
+ break;
+ }
+ }
+ /*
+ * If no option could be set, return an error:
+ */
+ if (!trace_options[i])
+ return -EINVAL;
+
+ filp->f_pos += cnt;
+
+ return cnt;
+}
+
+static struct file_operations tracing_iter_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_iter_ctrl_read,
+ .write = tracing_iter_ctrl_write,
+};
+
+static const char readme_msg[] =
+ "tracing mini-HOWTO:\n\n"
+ "# mkdir /debug\n"
+ "# mount -t debugfs nodev /debug\n\n"
+ "# cat /debug/tracing/available_tracers\n"
+ "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n"
+ "# cat /debug/tracing/current_tracer\n"
+ "none\n"
+ "# echo sched_switch > /debug/tracing/current_tracer\n"
+ "# cat /debug/tracing/current_tracer\n"
+ "sched_switch\n"
+ "# cat /debug/tracing/iter_ctrl\n"
+ "noprint-parent nosym-offset nosym-addr noverbose\n"
+ "# echo print-parent > /debug/tracing/iter_ctrl\n"
+ "# echo 1 > /debug/tracing/tracing_enabled\n"
+ "# cat /debug/tracing/trace > /tmp/trace.txt\n"
+ "echo 0 > /debug/tracing/tracing_enabled\n"
+;
+
+static ssize_t
+tracing_readme_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return simple_read_from_buffer(ubuf, cnt, ppos,
+ readme_msg, strlen(readme_msg));
+}
+
+static struct file_operations tracing_readme_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_readme_read,
+};
+
+static ssize_t
+tracing_ctrl_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = sprintf(buf, "%ld\n", tr->ctrl);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+tracing_ctrl_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ char buf[64];
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ val = !!val;
+
+ mutex_lock(&trace_types_lock);
+ if (tr->ctrl ^ val) {
+ if (val)
+ tracer_enabled = 1;
+ else
+ tracer_enabled = 0;
+
+ tr->ctrl = val;
+
+ if (current_trace && current_trace->ctrl_update)
+ current_trace->ctrl_update(tr);
+ }
+ mutex_unlock(&trace_types_lock);
+
+ filp->f_pos += cnt;
+
+ return cnt;
+}
+
+static ssize_t
+tracing_set_trace_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[max_tracer_type_len+2];
+ int r;
+
+ mutex_lock(&trace_types_lock);
+ if (current_trace)
+ r = sprintf(buf, "%s\n", current_trace->name);
+ else
+ r = sprintf(buf, "\n");
+ mutex_unlock(&trace_types_lock);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+tracing_set_trace_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = &global_trace;
+ struct tracer *t;
+ char buf[max_tracer_type_len+1];
+ int i;
+
+ if (cnt > max_tracer_type_len)
+ cnt = max_tracer_type_len;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ /* strip ending whitespace. */
+ for (i = cnt - 1; i > 0 && isspace(buf[i]); i--)
+ buf[i] = 0;
+
+ mutex_lock(&trace_types_lock);
+ for (t = trace_types; t; t = t->next) {
+ if (strcmp(t->name, buf) == 0)
+ break;
+ }
+ if (!t || t == current_trace)
+ goto out;
+
+ if (current_trace && current_trace->reset)
+ current_trace->reset(tr);
+
+ current_trace = t;
+ if (t->init)
+ t->init(tr);
+
+ out:
+ mutex_unlock(&trace_types_lock);
+
+ filp->f_pos += cnt;
+
+ return cnt;
+}
+
+static ssize_t
+tracing_max_lat_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long *ptr = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = snprintf(buf, sizeof(buf), "%ld\n",
+ *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr));
+ if (r > sizeof(buf))
+ r = sizeof(buf);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+tracing_max_lat_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ long *ptr = filp->private_data;
+ char buf[64];
+ long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ *ptr = val * 1000;
+
+ return cnt;
+}
+
+static atomic_t tracing_reader;
+
+static int tracing_open_pipe(struct inode *inode, struct file *filp)
+{
+ struct trace_iterator *iter;
+
+ if (tracing_disabled)
+ return -ENODEV;
+
+ /* We only allow for reader of the pipe */
+ if (atomic_inc_return(&tracing_reader) != 1) {
+ atomic_dec(&tracing_reader);
+ return -EBUSY;
+ }
+
+ /* create a buffer to store the information to pass to userspace */
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return -ENOMEM;
+
+ mutex_lock(&trace_types_lock);
+ iter->tr = &global_trace;
+ iter->trace = current_trace;
+ filp->private_data = iter;
+
+ if (iter->trace->pipe_open)
+ iter->trace->pipe_open(iter);
+ mutex_unlock(&trace_types_lock);
+
+ return 0;
+}
+
+static int tracing_release_pipe(struct inode *inode, struct file *file)
+{
+ struct trace_iterator *iter = file->private_data;
+
+ kfree(iter);
+ atomic_dec(&tracing_reader);
+
+ return 0;
+}
+
+static unsigned int
+tracing_poll_pipe(struct file *filp, poll_table *poll_table)
+{
+ struct trace_iterator *iter = filp->private_data;
+
+ if (trace_flags & TRACE_ITER_BLOCK) {
+ /*
+ * Always select as readable when in blocking mode
+ */
+ return POLLIN | POLLRDNORM;
+ } else {
+ if (!trace_empty(iter))
+ return POLLIN | POLLRDNORM;
+ poll_wait(filp, &trace_wait, poll_table);
+ if (!trace_empty(iter))
+ return POLLIN | POLLRDNORM;
+
+ return 0;
+ }
+}
+
+/*
+ * Consumer reader.
+ */
+static ssize_t
+tracing_read_pipe(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_iterator *iter = filp->private_data;
+ struct trace_array_cpu *data;
+ static cpumask_t mask;
+ unsigned long flags;
+#ifdef CONFIG_FTRACE
+ int ftrace_save;
+#endif
+ int cpu;
+ ssize_t sret;
+
+ /* return any leftover data */
+ sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
+ if (sret != -EBUSY)
+ return sret;
+ sret = 0;
+
+ trace_seq_reset(&iter->seq);
+
+ mutex_lock(&trace_types_lock);
+ if (iter->trace->read) {
+ sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
+ if (sret)
+ goto out;
+ }
+
+ while (trace_empty(iter)) {
+
+ if ((filp->f_flags & O_NONBLOCK)) {
+ sret = -EAGAIN;
+ goto out;
+ }
+
+ /*
+ * This is a make-shift waitqueue. The reason we don't use
+ * an actual wait queue is because:
+ * 1) we only ever have one waiter
+ * 2) the tracing, traces all functions, we don't want
+ * the overhead of calling wake_up and friends
+ * (and tracing them too)
+ * Anyway, this is really very primitive wakeup.
+ */
+ set_current_state(TASK_INTERRUPTIBLE);
+ iter->tr->waiter = current;
+
+ mutex_unlock(&trace_types_lock);
+
+ /* sleep for 100 msecs, and try again. */
+ schedule_timeout(HZ/10);
+
+ mutex_lock(&trace_types_lock);
+
+ iter->tr->waiter = NULL;
+
+ if (signal_pending(current)) {
+ sret = -EINTR;
+ goto out;
+ }
+
+ if (iter->trace != current_trace)
+ goto out;
+
+ /*
+ * We block until we read something and tracing is disabled.
+ * We still block if tracing is disabled, but we have never
+ * read anything. This allows a user to cat this file, and
+ * then enable tracing. But after we have read something,
+ * we give an EOF when tracing is again disabled.
+ *
+ * iter->pos will be 0 if we haven't read anything.
+ */
+ if (!tracer_enabled && iter->pos)
+ break;
+
+ continue;
+ }
+
+ /* stop when tracing is finished */
+ if (trace_empty(iter))
+ goto out;
+
+ if (cnt >= PAGE_SIZE)
+ cnt = PAGE_SIZE - 1;
+
+ /* reset all but tr, trace, and overruns */
+ memset(&iter->seq, 0,
+ sizeof(struct trace_iterator) -
+ offsetof(struct trace_iterator, seq));
+ iter->pos = -1;
+
+ /*
+ * We need to stop all tracing on all CPUS to read the
+ * the next buffer. This is a bit expensive, but is
+ * not done often. We fill all what we can read,
+ * and then release the locks again.
+ */
+
+ cpus_clear(mask);
+ local_irq_save(flags);
+#ifdef CONFIG_FTRACE
+ ftrace_save = ftrace_enabled;
+ ftrace_enabled = 0;
+#endif
+ smp_wmb();
+ for_each_tracing_cpu(cpu) {
+ data = iter->tr->data[cpu];
+
+ if (!head_page(data) || !data->trace_idx)
+ continue;
+
+ atomic_inc(&data->disabled);
+ cpu_set(cpu, mask);
+ }
+
+ for_each_cpu_mask(cpu, mask) {
+ data = iter->tr->data[cpu];
+ __raw_spin_lock(&data->lock);
+
+ if (data->overrun > iter->last_overrun[cpu])
+ iter->overrun[cpu] +=
+ data->overrun - iter->last_overrun[cpu];
+ iter->last_overrun[cpu] = data->overrun;
+ }
+
+ while (find_next_entry_inc(iter) != NULL) {
+ int ret;
+ int len = iter->seq.len;
+
+ ret = print_trace_line(iter);
+ if (!ret) {
+ /* don't print partial lines */
+ iter->seq.len = len;
+ break;
+ }
+
+ trace_consume(iter);
+
+ if (iter->seq.len >= cnt)
+ break;
+ }
+
+ for_each_cpu_mask(cpu, mask) {
+ data = iter->tr->data[cpu];
+ __raw_spin_unlock(&data->lock);
+ }
+
+ for_each_cpu_mask(cpu, mask) {
+ data = iter->tr->data[cpu];
+ atomic_dec(&data->disabled);
+ }
+#ifdef CONFIG_FTRACE
+ ftrace_enabled = ftrace_save;
+#endif
+ local_irq_restore(flags);
+
+ /* Now copy what we have to the user */
+ sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
+ if (iter->seq.readpos >= iter->seq.len)
+ trace_seq_reset(&iter->seq);
+ if (sret == -EBUSY)
+ sret = 0;
+
+out:
+ mutex_unlock(&trace_types_lock);
+
+ return sret;
+}
+
+static ssize_t
+tracing_entries_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ struct trace_array *tr = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = sprintf(buf, "%lu\n", tr->entries);
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+tracing_entries_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long val;
+ char buf[64];
+ int i, ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ /* must have at least 1 entry */
+ if (!val)
+ return -EINVAL;
+
+ mutex_lock(&trace_types_lock);
+
+ if (current_trace != &no_tracer) {
+ cnt = -EBUSY;
+ pr_info("ftrace: set current_tracer to none"
+ " before modifying buffer size\n");
+ goto out;
+ }
+
+ if (val > global_trace.entries) {
+ long pages_requested;
+ unsigned long freeable_pages;
+
+ /* make sure we have enough memory before mapping */
+ pages_requested =
+ (val + (ENTRIES_PER_PAGE-1)) / ENTRIES_PER_PAGE;
+
+ /* account for each buffer (and max_tr) */
+ pages_requested *= tracing_nr_buffers * 2;
+
+ /* Check for overflow */
+ if (pages_requested < 0) {
+ cnt = -ENOMEM;
+ goto out;
+ }
+
+ freeable_pages = determine_dirtyable_memory();
+
+ /* we only allow to request 1/4 of useable memory */
+ if (pages_requested >
+ ((freeable_pages + tracing_pages_allocated) / 4)) {
+ cnt = -ENOMEM;
+ goto out;
+ }
+
+ while (global_trace.entries < val) {
+ if (trace_alloc_page()) {
+ cnt = -ENOMEM;
+ goto out;
+ }
+ /* double check that we don't go over the known pages */
+ if (tracing_pages_allocated > pages_requested)
+ break;
+ }
+
+ } else {
+ /* include the number of entries in val (inc of page entries) */
+ while (global_trace.entries > val + (ENTRIES_PER_PAGE - 1))
+ trace_free_page();
+ }
+
+ /* check integrity */
+ for_each_tracing_cpu(i)
+ check_pages(global_trace.data[i]);
+
+ filp->f_pos += cnt;
+
+ /* If check pages failed, return ENOMEM */
+ if (tracing_disabled)
+ cnt = -ENOMEM;
+ out:
+ max_tr.entries = global_trace.entries;
+ mutex_unlock(&trace_types_lock);
+
+ return cnt;
+}
+
+static struct file_operations tracing_max_lat_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_max_lat_read,
+ .write = tracing_max_lat_write,
+};
+
+static struct file_operations tracing_ctrl_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_ctrl_read,
+ .write = tracing_ctrl_write,
+};
+
+static struct file_operations set_tracer_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_set_trace_read,
+ .write = tracing_set_trace_write,
+};
+
+static struct file_operations tracing_pipe_fops = {
+ .open = tracing_open_pipe,
+ .poll = tracing_poll_pipe,
+ .read = tracing_read_pipe,
+ .release = tracing_release_pipe,
+};
+
+static struct file_operations tracing_entries_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_entries_read,
+ .write = tracing_entries_write,
+};
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+static ssize_t
+tracing_read_long(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ unsigned long *p = filp->private_data;
+ char buf[64];
+ int r;
+
+ r = sprintf(buf, "%ld\n", *p);
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static struct file_operations tracing_read_long_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_read_long,
+};
+#endif
+
+static struct dentry *d_tracer;
+
+struct dentry *tracing_init_dentry(void)
+{
+ static int once;
+
+ if (d_tracer)
+ return d_tracer;
+
+ d_tracer = debugfs_create_dir("tracing", NULL);
+
+ if (!d_tracer && !once) {
+ once = 1;
+ pr_warning("Could not create debugfs directory 'tracing'\n");
+ return NULL;
+ }
+
+ return d_tracer;
+}
+
+#ifdef CONFIG_FTRACE_SELFTEST
+/* Let selftest have access to static functions in this file */
+#include "trace_selftest.c"
+#endif
+
+static __init void tracer_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+
+ d_tracer = tracing_init_dentry();
+
+ entry = debugfs_create_file("tracing_enabled", 0644, d_tracer,
+ &global_trace, &tracing_ctrl_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'tracing_enabled' entry\n");
+
+ entry = debugfs_create_file("iter_ctrl", 0644, d_tracer,
+ NULL, &tracing_iter_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'iter_ctrl' entry\n");
+
+ entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer,
+ NULL, &tracing_cpumask_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'tracing_cpumask' entry\n");
+
+ entry = debugfs_create_file("latency_trace", 0444, d_tracer,
+ &global_trace, &tracing_lt_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'latency_trace' entry\n");
+
+ entry = debugfs_create_file("trace", 0444, d_tracer,
+ &global_trace, &tracing_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace' entry\n");
+
+ entry = debugfs_create_file("available_tracers", 0444, d_tracer,
+ &global_trace, &show_traces_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace' entry\n");
+
+ entry = debugfs_create_file("current_tracer", 0444, d_tracer,
+ &global_trace, &set_tracer_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace' entry\n");
+
+ entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer,
+ &tracing_max_latency,
+ &tracing_max_lat_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'tracing_max_latency' entry\n");
+
+ entry = debugfs_create_file("tracing_thresh", 0644, d_tracer,
+ &tracing_thresh, &tracing_max_lat_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'tracing_threash' entry\n");
+ entry = debugfs_create_file("README", 0644, d_tracer,
+ NULL, &tracing_readme_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'README' entry\n");
+
+ entry = debugfs_create_file("trace_pipe", 0644, d_tracer,
+ NULL, &tracing_pipe_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'tracing_threash' entry\n");
+
+ entry = debugfs_create_file("trace_entries", 0644, d_tracer,
+ &global_trace, &tracing_entries_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'tracing_threash' entry\n");
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+ entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer,
+ &ftrace_update_tot_cnt,
+ &tracing_read_long_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'dyn_ftrace_total_info' entry\n");
+#endif
+#ifdef CONFIG_SYSPROF_TRACER
+ init_tracer_sysprof_debugfs(d_tracer);
+#endif
+}
+
+static int trace_alloc_page(void)
+{
+ struct trace_array_cpu *data;
+ struct page *page, *tmp;
+ LIST_HEAD(pages);
+ void *array;
+ unsigned pages_allocated = 0;
+ int i;
+
+ /* first allocate a page for each CPU */
+ for_each_tracing_cpu(i) {
+ array = (void *)__get_free_page(GFP_KERNEL);
+ if (array == NULL) {
+ printk(KERN_ERR "tracer: failed to allocate page"
+ "for trace buffer!\n");
+ goto free_pages;
+ }
+
+ pages_allocated++;
+ page = virt_to_page(array);
+ list_add(&page->lru, &pages);
+
+/* Only allocate if we are actually using the max trace */
+#ifdef CONFIG_TRACER_MAX_TRACE
+ array = (void *)__get_free_page(GFP_KERNEL);
+ if (array == NULL) {
+ printk(KERN_ERR "tracer: failed to allocate page"
+ "for trace buffer!\n");
+ goto free_pages;
+ }
+ pages_allocated++;
+ page = virt_to_page(array);
+ list_add(&page->lru, &pages);
+#endif
+ }
+
+ /* Now that we successfully allocate a page per CPU, add them */
+ for_each_tracing_cpu(i) {
+ data = global_trace.data[i];
+ page = list_entry(pages.next, struct page, lru);
+ list_del_init(&page->lru);
+ list_add_tail(&page->lru, &data->trace_pages);
+ ClearPageLRU(page);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ data = max_tr.data[i];
+ page = list_entry(pages.next, struct page, lru);
+ list_del_init(&page->lru);
+ list_add_tail(&page->lru, &data->trace_pages);
+ SetPageLRU(page);
+#endif
+ }
+ tracing_pages_allocated += pages_allocated;
+ global_trace.entries += ENTRIES_PER_PAGE;
+
+ return 0;
+
+ free_pages:
+ list_for_each_entry_safe(page, tmp, &pages, lru) {
+ list_del_init(&page->lru);
+ __free_page(page);
+ }
+ return -ENOMEM;
+}
+
+static int trace_free_page(void)
+{
+ struct trace_array_cpu *data;
+ struct page *page;
+ struct list_head *p;
+ int i;
+ int ret = 0;
+
+ /* free one page from each buffer */
+ for_each_tracing_cpu(i) {
+ data = global_trace.data[i];
+ p = data->trace_pages.next;
+ if (p == &data->trace_pages) {
+ /* should never happen */
+ WARN_ON(1);
+ tracing_disabled = 1;
+ ret = -1;
+ break;
+ }
+ page = list_entry(p, struct page, lru);
+ ClearPageLRU(page);
+ list_del(&page->lru);
+ tracing_pages_allocated--;
+ tracing_pages_allocated--;
+ __free_page(page);
+
+ tracing_reset(data);
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ data = max_tr.data[i];
+ p = data->trace_pages.next;
+ if (p == &data->trace_pages) {
+ /* should never happen */
+ WARN_ON(1);
+ tracing_disabled = 1;
+ ret = -1;
+ break;
+ }
+ page = list_entry(p, struct page, lru);
+ ClearPageLRU(page);
+ list_del(&page->lru);
+ __free_page(page);
+
+ tracing_reset(data);
+#endif
+ }
+ global_trace.entries -= ENTRIES_PER_PAGE;
+
+ return ret;
+}
+
+__init static int tracer_alloc_buffers(void)
+{
+ struct trace_array_cpu *data;
+ void *array;
+ struct page *page;
+ int pages = 0;
+ int ret = -ENOMEM;
+ int i;
+
+ /* TODO: make the number of buffers hot pluggable with CPUS */
+ tracing_nr_buffers = num_possible_cpus();
+ tracing_buffer_mask = cpu_possible_map;
+
+ /* Allocate the first page for all buffers */
+ for_each_tracing_cpu(i) {
+ data = global_trace.data[i] = &per_cpu(global_trace_cpu, i);
+ max_tr.data[i] = &per_cpu(max_data, i);
+
+ array = (void *)__get_free_page(GFP_KERNEL);
+ if (array == NULL) {
+ printk(KERN_ERR "tracer: failed to allocate page"
+ "for trace buffer!\n");
+ goto free_buffers;
+ }
+
+ /* set the array to the list */
+ INIT_LIST_HEAD(&data->trace_pages);
+ page = virt_to_page(array);
+ list_add(&page->lru, &data->trace_pages);
+ /* use the LRU flag to differentiate the two buffers */
+ ClearPageLRU(page);
+
+ data->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+ max_tr.data[i]->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+
+/* Only allocate if we are actually using the max trace */
+#ifdef CONFIG_TRACER_MAX_TRACE
+ array = (void *)__get_free_page(GFP_KERNEL);
+ if (array == NULL) {
+ printk(KERN_ERR "tracer: failed to allocate page"
+ "for trace buffer!\n");
+ goto free_buffers;
+ }
+
+ INIT_LIST_HEAD(&max_tr.data[i]->trace_pages);
+ page = virt_to_page(array);
+ list_add(&page->lru, &max_tr.data[i]->trace_pages);
+ SetPageLRU(page);
+#endif
+ }
+
+ /*
+ * Since we allocate by orders of pages, we may be able to
+ * round up a bit.
+ */
+ global_trace.entries = ENTRIES_PER_PAGE;
+ pages++;
+
+ while (global_trace.entries < trace_nr_entries) {
+ if (trace_alloc_page())
+ break;
+ pages++;
+ }
+ max_tr.entries = global_trace.entries;
+
+ pr_info("tracer: %d pages allocated for %ld entries of %ld bytes\n",
+ pages, trace_nr_entries, (long)TRACE_ENTRY_SIZE);
+ pr_info(" actual entries %ld\n", global_trace.entries);
+
+ tracer_init_debugfs();
+
+ trace_init_cmdlines();
+
+ register_tracer(&no_tracer);
+ current_trace = &no_tracer;
+
+ /* All seems OK, enable tracing */
+ global_trace.ctrl = tracer_enabled;
+ tracing_disabled = 0;
+
+ return 0;
+
+ free_buffers:
+ for (i-- ; i >= 0; i--) {
+ struct page *page, *tmp;
+ struct trace_array_cpu *data = global_trace.data[i];
+
+ if (data) {
+ list_for_each_entry_safe(page, tmp,
+ &data->trace_pages, lru) {
+ list_del_init(&page->lru);
+ __free_page(page);
+ }
+ }
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+ data = max_tr.data[i];
+ if (data) {
+ list_for_each_entry_safe(page, tmp,
+ &data->trace_pages, lru) {
+ list_del_init(&page->lru);
+ __free_page(page);
+ }
+ }
+#endif
+ }
+ return ret;
+}
+fs_initcall(tracer_alloc_buffers);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
new file mode 100644
index 00000000000..f69f86788c2
--- /dev/null
+++ b/kernel/trace/trace.h
@@ -0,0 +1,339 @@
+#ifndef _LINUX_KERNEL_TRACE_H
+#define _LINUX_KERNEL_TRACE_H
+
+#include <linux/fs.h>
+#include <asm/atomic.h>
+#include <linux/sched.h>
+#include <linux/clocksource.h>
+#include <linux/mmiotrace.h>
+
+enum trace_type {
+ __TRACE_FIRST_TYPE = 0,
+
+ TRACE_FN,
+ TRACE_CTX,
+ TRACE_WAKE,
+ TRACE_STACK,
+ TRACE_SPECIAL,
+ TRACE_MMIO_RW,
+ TRACE_MMIO_MAP,
+
+ __TRACE_LAST_TYPE
+};
+
+/*
+ * Function trace entry - function address and parent function addres:
+ */
+struct ftrace_entry {
+ unsigned long ip;
+ unsigned long parent_ip;
+};
+
+/*
+ * Context switch trace entry - which task (and prio) we switched from/to:
+ */
+struct ctx_switch_entry {
+ unsigned int prev_pid;
+ unsigned char prev_prio;
+ unsigned char prev_state;
+ unsigned int next_pid;
+ unsigned char next_prio;
+ unsigned char next_state;
+};
+
+/*
+ * Special (free-form) trace entry:
+ */
+struct special_entry {
+ unsigned long arg1;
+ unsigned long arg2;
+ unsigned long arg3;
+};
+
+/*
+ * Stack-trace entry:
+ */
+
+#define FTRACE_STACK_ENTRIES 8
+
+struct stack_entry {
+ unsigned long caller[FTRACE_STACK_ENTRIES];
+};
+
+/*
+ * The trace entry - the most basic unit of tracing. This is what
+ * is printed in the end as a single line in the trace output, such as:
+ *
+ * bash-15816 [01] 235.197585: idle_cpu <- irq_enter
+ */
+struct trace_entry {
+ char type;
+ char cpu;
+ char flags;
+ char preempt_count;
+ int pid;
+ cycle_t t;
+ union {
+ struct ftrace_entry fn;
+ struct ctx_switch_entry ctx;
+ struct special_entry special;
+ struct stack_entry stack;
+ struct mmiotrace_rw mmiorw;
+ struct mmiotrace_map mmiomap;
+ };
+};
+
+#define TRACE_ENTRY_SIZE sizeof(struct trace_entry)
+
+/*
+ * The CPU trace array - it consists of thousands of trace entries
+ * plus some other descriptor data: (for example which task started
+ * the trace, etc.)
+ */
+struct trace_array_cpu {
+ struct list_head trace_pages;
+ atomic_t disabled;
+ raw_spinlock_t lock;
+ struct lock_class_key lock_key;
+
+ /* these fields get copied into max-trace: */
+ unsigned trace_head_idx;
+ unsigned trace_tail_idx;
+ void *trace_head; /* producer */
+ void *trace_tail; /* consumer */
+ unsigned long trace_idx;
+ unsigned long overrun;
+ unsigned long saved_latency;
+ unsigned long critical_start;
+ unsigned long critical_end;
+ unsigned long critical_sequence;
+ unsigned long nice;
+ unsigned long policy;
+ unsigned long rt_priority;
+ cycle_t preempt_timestamp;
+ pid_t pid;
+ uid_t uid;
+ char comm[TASK_COMM_LEN];
+};
+
+struct trace_iterator;
+
+/*
+ * The trace array - an array of per-CPU trace arrays. This is the
+ * highest level data structure that individual tracers deal with.
+ * They have on/off state as well:
+ */
+struct trace_array {
+ unsigned long entries;
+ long ctrl;
+ int cpu;
+ cycle_t time_start;
+ struct task_struct *waiter;
+ struct trace_array_cpu *data[NR_CPUS];
+};
+
+/*
+ * A specific tracer, represented by methods that operate on a trace array:
+ */
+struct tracer {
+ const char *name;
+ void (*init)(struct trace_array *tr);
+ void (*reset)(struct trace_array *tr);
+ void (*open)(struct trace_iterator *iter);
+ void (*pipe_open)(struct trace_iterator *iter);
+ void (*close)(struct trace_iterator *iter);
+ void (*start)(struct trace_iterator *iter);
+ void (*stop)(struct trace_iterator *iter);
+ ssize_t (*read)(struct trace_iterator *iter,
+ struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos);
+ void (*ctrl_update)(struct trace_array *tr);
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+ int (*selftest)(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+ int (*print_line)(struct trace_iterator *iter);
+ struct tracer *next;
+ int print_max;
+};
+
+struct trace_seq {
+ unsigned char buffer[PAGE_SIZE];
+ unsigned int len;
+ unsigned int readpos;
+};
+
+/*
+ * Trace iterator - used by printout routines who present trace
+ * results to users and which routines might sleep, etc:
+ */
+struct trace_iterator {
+ struct trace_array *tr;
+ struct tracer *trace;
+ void *private;
+ long last_overrun[NR_CPUS];
+ long overrun[NR_CPUS];
+
+ /* The below is zeroed out in pipe_read */
+ struct trace_seq seq;
+ struct trace_entry *ent;
+ int cpu;
+
+ struct trace_entry *prev_ent;
+ int prev_cpu;
+
+ unsigned long iter_flags;
+ loff_t pos;
+ unsigned long next_idx[NR_CPUS];
+ struct list_head *next_page[NR_CPUS];
+ unsigned next_page_idx[NR_CPUS];
+ long idx;
+};
+
+void tracing_reset(struct trace_array_cpu *data);
+int tracing_open_generic(struct inode *inode, struct file *filp);
+struct dentry *tracing_init_dentry(void);
+void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
+
+void ftrace(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long ip,
+ unsigned long parent_ip,
+ unsigned long flags);
+void tracing_sched_switch_trace(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned long flags);
+void tracing_record_cmdline(struct task_struct *tsk);
+
+void tracing_sched_wakeup_trace(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct task_struct *wakee,
+ struct task_struct *cur,
+ unsigned long flags);
+void trace_special(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long arg1,
+ unsigned long arg2,
+ unsigned long arg3);
+void trace_function(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long ip,
+ unsigned long parent_ip,
+ unsigned long flags);
+
+void tracing_start_cmdline_record(void);
+void tracing_stop_cmdline_record(void);
+int register_tracer(struct tracer *type);
+void unregister_tracer(struct tracer *type);
+
+extern unsigned long nsecs_to_usecs(unsigned long nsecs);
+
+extern unsigned long tracing_max_latency;
+extern unsigned long tracing_thresh;
+
+void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
+void update_max_tr_single(struct trace_array *tr,
+ struct task_struct *tsk, int cpu);
+
+extern cycle_t ftrace_now(int cpu);
+
+#ifdef CONFIG_FTRACE
+void tracing_start_function_trace(void);
+void tracing_stop_function_trace(void);
+#else
+# define tracing_start_function_trace() do { } while (0)
+# define tracing_stop_function_trace() do { } while (0)
+#endif
+
+#ifdef CONFIG_CONTEXT_SWITCH_TRACER
+typedef void
+(*tracer_switch_func_t)(void *private,
+ void *__rq,
+ struct task_struct *prev,
+ struct task_struct *next);
+
+struct tracer_switch_ops {
+ tracer_switch_func_t func;
+ void *private;
+ struct tracer_switch_ops *next;
+};
+
+#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+extern unsigned long ftrace_update_tot_cnt;
+#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
+extern int DYN_FTRACE_TEST_NAME(void);
+#endif
+
+#ifdef CONFIG_MMIOTRACE
+extern void __trace_mmiotrace_rw(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct mmiotrace_rw *rw);
+extern void __trace_mmiotrace_map(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ struct mmiotrace_map *map);
+#endif
+
+#ifdef CONFIG_FTRACE_STARTUP_TEST
+#ifdef CONFIG_FTRACE
+extern int trace_selftest_startup_function(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#ifdef CONFIG_IRQSOFF_TRACER
+extern int trace_selftest_startup_irqsoff(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#ifdef CONFIG_PREEMPT_TRACER
+extern int trace_selftest_startup_preemptoff(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
+extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#ifdef CONFIG_SCHED_TRACER
+extern int trace_selftest_startup_wakeup(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#ifdef CONFIG_CONTEXT_SWITCH_TRACER
+extern int trace_selftest_startup_sched_switch(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#ifdef CONFIG_SYSPROF_TRACER
+extern int trace_selftest_startup_sysprof(struct tracer *trace,
+ struct trace_array *tr);
+#endif
+#endif /* CONFIG_FTRACE_STARTUP_TEST */
+
+extern void *head_page(struct trace_array_cpu *data);
+extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
+extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
+ size_t cnt);
+extern long ns2usecs(cycle_t nsec);
+
+extern unsigned long trace_flags;
+
+/*
+ * trace_iterator_flags is an enumeration that defines bit
+ * positions into trace_flags that controls the output.
+ *
+ * NOTE: These bits must match the trace_options array in
+ * trace.c.
+ */
+enum trace_iterator_flags {
+ TRACE_ITER_PRINT_PARENT = 0x01,
+ TRACE_ITER_SYM_OFFSET = 0x02,
+ TRACE_ITER_SYM_ADDR = 0x04,
+ TRACE_ITER_VERBOSE = 0x08,
+ TRACE_ITER_RAW = 0x10,
+ TRACE_ITER_HEX = 0x20,
+ TRACE_ITER_BIN = 0x40,
+ TRACE_ITER_BLOCK = 0x80,
+ TRACE_ITER_STACKTRACE = 0x100,
+ TRACE_ITER_SCHED_TREE = 0x200,
+};
+
+#endif /* _LINUX_KERNEL_TRACE_H */
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
new file mode 100644
index 00000000000..31214489797
--- /dev/null
+++ b/kernel/trace/trace_functions.c
@@ -0,0 +1,81 @@
+/*
+ * ring buffer based function tracer
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ * Based on code from the latency_tracer, that is:
+ *
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 William Lee Irwin III
+ */
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/fs.h>
+
+#include "trace.h"
+
+static void function_reset(struct trace_array *tr)
+{
+ int cpu;
+
+ tr->time_start = ftrace_now(tr->cpu);
+
+ for_each_online_cpu(cpu)
+ tracing_reset(tr->data[cpu]);
+}
+
+static void start_function_trace(struct trace_array *tr)
+{
+ tr->cpu = get_cpu();
+ function_reset(tr);
+ put_cpu();
+
+ tracing_start_cmdline_record();
+ tracing_start_function_trace();
+}
+
+static void stop_function_trace(struct trace_array *tr)
+{
+ tracing_stop_function_trace();
+ tracing_stop_cmdline_record();
+}
+
+static void function_trace_init(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ start_function_trace(tr);
+}
+
+static void function_trace_reset(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ stop_function_trace(tr);
+}
+
+static void function_trace_ctrl_update(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ start_function_trace(tr);
+ else
+ stop_function_trace(tr);
+}
+
+static struct tracer function_trace __read_mostly =
+{
+ .name = "ftrace",
+ .init = function_trace_init,
+ .reset = function_trace_reset,
+ .ctrl_update = function_trace_ctrl_update,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_function,
+#endif
+};
+
+static __init int init_function_trace(void)
+{
+ return register_tracer(&function_trace);
+}
+
+device_initcall(init_function_trace);
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
new file mode 100644
index 00000000000..421d6fe3650
--- /dev/null
+++ b/kernel/trace/trace_irqsoff.c
@@ -0,0 +1,486 @@
+/*
+ * trace irqs off criticall timings
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ * From code in the latency_tracer, that is:
+ *
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 William Lee Irwin III
+ */
+#include <linux/kallsyms.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/ftrace.h>
+#include <linux/fs.h>
+
+#include "trace.h"
+
+static struct trace_array *irqsoff_trace __read_mostly;
+static int tracer_enabled __read_mostly;
+
+static DEFINE_PER_CPU(int, tracing_cpu);
+
+static DEFINE_SPINLOCK(max_trace_lock);
+
+enum {
+ TRACER_IRQS_OFF = (1 << 1),
+ TRACER_PREEMPT_OFF = (1 << 2),
+};
+
+static int trace_type __read_mostly;
+
+#ifdef CONFIG_PREEMPT_TRACER
+static inline int
+preempt_trace(void)
+{
+ return ((trace_type & TRACER_PREEMPT_OFF) && preempt_count());
+}
+#else
+# define preempt_trace() (0)
+#endif
+
+#ifdef CONFIG_IRQSOFF_TRACER
+static inline int
+irq_trace(void)
+{
+ return ((trace_type & TRACER_IRQS_OFF) &&
+ irqs_disabled());
+}
+#else
+# define irq_trace() (0)
+#endif
+
+/*
+ * Sequence count - we record it when starting a measurement and
+ * skip the latency if the sequence has changed - some other section
+ * did a maximum and could disturb our measurement with serial console
+ * printouts, etc. Truly coinciding maximum latencies should be rare
+ * and what happens together happens separately as well, so this doesnt
+ * decrease the validity of the maximum found:
+ */
+static __cacheline_aligned_in_smp unsigned long max_sequence;
+
+#ifdef CONFIG_FTRACE
+/*
+ * irqsoff uses its own tracer function to keep the overhead down:
+ */
+static void
+irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct trace_array *tr = irqsoff_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ /*
+ * Does not matter if we preempt. We test the flags
+ * afterward, to see if irqs are disabled or not.
+ * If we preempt and get a false positive, the flags
+ * test will fail.
+ */
+ cpu = raw_smp_processor_id();
+ if (likely(!per_cpu(tracing_cpu, cpu)))
+ return;
+
+ local_save_flags(flags);
+ /* slight chance to get a false positive on tracing_cpu */
+ if (!irqs_disabled_flags(flags))
+ return;
+
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1))
+ trace_function(tr, data, ip, parent_ip, flags);
+
+ atomic_dec(&data->disabled);
+}
+
+static struct ftrace_ops trace_ops __read_mostly =
+{
+ .func = irqsoff_tracer_call,
+};
+#endif /* CONFIG_FTRACE */
+
+/*
+ * Should this new latency be reported/recorded?
+ */
+static int report_latency(cycle_t delta)
+{
+ if (tracing_thresh) {
+ if (delta < tracing_thresh)
+ return 0;
+ } else {
+ if (delta <= tracing_max_latency)
+ return 0;
+ }
+ return 1;
+}
+
+static void
+check_critical_timing(struct trace_array *tr,
+ struct trace_array_cpu *data,
+ unsigned long parent_ip,
+ int cpu)
+{
+ unsigned long latency, t0, t1;
+ cycle_t T0, T1, delta;
+ unsigned long flags;
+
+ /*
+ * usecs conversion is slow so we try to delay the conversion
+ * as long as possible:
+ */
+ T0 = data->preempt_timestamp;
+ T1 = ftrace_now(cpu);
+ delta = T1-T0;
+
+ local_save_flags(flags);
+
+ if (!report_latency(delta))
+ goto out;
+
+ spin_lock_irqsave(&max_trace_lock, flags);
+
+ /* check if we are still the max latency */
+ if (!report_latency(delta))
+ goto out_unlock;
+
+ trace_function(tr, data, CALLER_ADDR0, parent_ip, flags);
+
+ latency = nsecs_to_usecs(delta);
+
+ if (data->critical_sequence != max_sequence)
+ goto out_unlock;
+
+ tracing_max_latency = delta;
+ t0 = nsecs_to_usecs(T0);
+ t1 = nsecs_to_usecs(T1);
+
+ data->critical_end = parent_ip;
+
+ update_max_tr_single(tr, current, cpu);
+
+ max_sequence++;
+
+out_unlock:
+ spin_unlock_irqrestore(&max_trace_lock, flags);
+
+out:
+ data->critical_sequence = max_sequence;
+ data->preempt_timestamp = ftrace_now(cpu);
+ tracing_reset(data);
+ trace_function(tr, data, CALLER_ADDR0, parent_ip, flags);
+}
+
+static inline void
+start_critical_timing(unsigned long ip, unsigned long parent_ip)
+{
+ int cpu;
+ struct trace_array *tr = irqsoff_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+
+ if (likely(!tracer_enabled))
+ return;
+
+ cpu = raw_smp_processor_id();
+
+ if (per_cpu(tracing_cpu, cpu))
+ return;
+
+ data = tr->data[cpu];
+
+ if (unlikely(!data) || atomic_read(&data->disabled))
+ return;
+
+ atomic_inc(&data->disabled);
+
+ data->critical_sequence = max_sequence;
+ data->preempt_timestamp = ftrace_now(cpu);
+ data->critical_start = parent_ip ? : ip;
+ tracing_reset(data);
+
+ local_save_flags(flags);
+
+ trace_function(tr, data, ip, parent_ip, flags);
+
+ per_cpu(tracing_cpu, cpu) = 1;
+
+ atomic_dec(&data->disabled);
+}
+
+static inline void
+stop_critical_timing(unsigned long ip, unsigned long parent_ip)
+{
+ int cpu;
+ struct trace_array *tr = irqsoff_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+
+ cpu = raw_smp_processor_id();
+ /* Always clear the tracing cpu on stopping the trace */
+ if (unlikely(per_cpu(tracing_cpu, cpu)))
+ per_cpu(tracing_cpu, cpu) = 0;
+ else
+ return;
+
+ if (!tracer_enabled)
+ return;
+
+ data = tr->data[cpu];
+
+ if (unlikely(!data) || unlikely(!head_page(data)) ||
+ !data->critical_start || atomic_read(&data->disabled))
+ return;
+
+ atomic_inc(&data->disabled);
+
+ local_save_flags(flags);
+ trace_function(tr, data, ip, parent_ip, flags);
+ check_critical_timing(tr, data, parent_ip ? : ip, cpu);
+ data->critical_start = 0;
+ atomic_dec(&data->disabled);
+}
+
+/* start and stop critical timings used to for stoppage (in idle) */
+void start_critical_timings(void)
+{
+ if (preempt_trace() || irq_trace())
+ start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+}
+
+void stop_critical_timings(void)
+{
+ if (preempt_trace() || irq_trace())
+ stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+}
+
+#ifdef CONFIG_IRQSOFF_TRACER
+#ifdef CONFIG_PROVE_LOCKING
+void time_hardirqs_on(unsigned long a0, unsigned long a1)
+{
+ if (!preempt_trace() && irq_trace())
+ stop_critical_timing(a0, a1);
+}
+
+void time_hardirqs_off(unsigned long a0, unsigned long a1)
+{
+ if (!preempt_trace() && irq_trace())
+ start_critical_timing(a0, a1);
+}
+
+#else /* !CONFIG_PROVE_LOCKING */
+
+/*
+ * Stubs:
+ */
+
+void early_boot_irqs_off(void)
+{
+}
+
+void early_boot_irqs_on(void)
+{
+}
+
+void trace_softirqs_on(unsigned long ip)
+{
+}
+
+void trace_softirqs_off(unsigned long ip)
+{
+}
+
+inline void print_irqtrace_events(struct task_struct *curr)
+{
+}
+
+/*
+ * We are only interested in hardirq on/off events:
+ */
+void trace_hardirqs_on(void)
+{
+ if (!preempt_trace() && irq_trace())
+ stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+}
+EXPORT_SYMBOL(trace_hardirqs_on);
+
+void trace_hardirqs_off(void)
+{
+ if (!preempt_trace() && irq_trace())
+ start_critical_timing(CALLER_ADDR0, CALLER_ADDR1);
+}
+EXPORT_SYMBOL(trace_hardirqs_off);
+
+void trace_hardirqs_on_caller(unsigned long caller_addr)
+{
+ if (!preempt_trace() && irq_trace())
+ stop_critical_timing(CALLER_ADDR0, caller_addr);
+}
+EXPORT_SYMBOL(trace_hardirqs_on_caller);
+
+void trace_hardirqs_off_caller(unsigned long caller_addr)
+{
+ if (!preempt_trace() && irq_trace())
+ start_critical_timing(CALLER_ADDR0, caller_addr);
+}
+EXPORT_SYMBOL(trace_hardirqs_off_caller);
+
+#endif /* CONFIG_PROVE_LOCKING */
+#endif /* CONFIG_IRQSOFF_TRACER */
+
+#ifdef CONFIG_PREEMPT_TRACER
+void trace_preempt_on(unsigned long a0, unsigned long a1)
+{
+ stop_critical_timing(a0, a1);
+}
+
+void trace_preempt_off(unsigned long a0, unsigned long a1)
+{
+ start_critical_timing(a0, a1);
+}
+#endif /* CONFIG_PREEMPT_TRACER */
+
+static void start_irqsoff_tracer(struct trace_array *tr)
+{
+ register_ftrace_function(&trace_ops);
+ tracer_enabled = 1;
+}
+
+static void stop_irqsoff_tracer(struct trace_array *tr)
+{
+ tracer_enabled = 0;
+ unregister_ftrace_function(&trace_ops);
+}
+
+static void __irqsoff_tracer_init(struct trace_array *tr)
+{
+ irqsoff_trace = tr;
+ /* make sure that the tracer is visible */
+ smp_wmb();
+
+ if (tr->ctrl)
+ start_irqsoff_tracer(tr);
+}
+
+static void irqsoff_tracer_reset(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ stop_irqsoff_tracer(tr);
+}
+
+static void irqsoff_tracer_ctrl_update(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ start_irqsoff_tracer(tr);
+ else
+ stop_irqsoff_tracer(tr);
+}
+
+static void irqsoff_tracer_open(struct trace_iterator *iter)
+{
+ /* stop the trace while dumping */
+ if (iter->tr->ctrl)
+ stop_irqsoff_tracer(iter->tr);
+}
+
+static void irqsoff_tracer_close(struct trace_iterator *iter)
+{
+ if (iter->tr->ctrl)
+ start_irqsoff_tracer(iter->tr);
+}
+
+#ifdef CONFIG_IRQSOFF_TRACER
+static void irqsoff_tracer_init(struct trace_array *tr)
+{
+ trace_type = TRACER_IRQS_OFF;
+
+ __irqsoff_tracer_init(tr);
+}
+static struct tracer irqsoff_tracer __read_mostly =
+{
+ .name = "irqsoff",
+ .init = irqsoff_tracer_init,
+ .reset = irqsoff_tracer_reset,
+ .open = irqsoff_tracer_open,
+ .close = irqsoff_tracer_close,
+ .ctrl_update = irqsoff_tracer_ctrl_update,
+ .print_max = 1,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_irqsoff,
+#endif
+};
+# define register_irqsoff(trace) register_tracer(&trace)
+#else
+# define register_irqsoff(trace) do { } while (0)
+#endif
+
+#ifdef CONFIG_PREEMPT_TRACER
+static void preemptoff_tracer_init(struct trace_array *tr)
+{
+ trace_type = TRACER_PREEMPT_OFF;
+
+ __irqsoff_tracer_init(tr);
+}
+
+static struct tracer preemptoff_tracer __read_mostly =
+{
+ .name = "preemptoff",
+ .init = preemptoff_tracer_init,
+ .reset = irqsoff_tracer_reset,
+ .open = irqsoff_tracer_open,
+ .close = irqsoff_tracer_close,
+ .ctrl_update = irqsoff_tracer_ctrl_update,
+ .print_max = 1,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_preemptoff,
+#endif
+};
+# define register_preemptoff(trace) register_tracer(&trace)
+#else
+# define register_preemptoff(trace) do { } while (0)
+#endif
+
+#if defined(CONFIG_IRQSOFF_TRACER) && \
+ defined(CONFIG_PREEMPT_TRACER)
+
+static void preemptirqsoff_tracer_init(struct trace_array *tr)
+{
+ trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF;
+
+ __irqsoff_tracer_init(tr);
+}
+
+static struct tracer preemptirqsoff_tracer __read_mostly =
+{
+ .name = "preemptirqsoff",
+ .init = preemptirqsoff_tracer_init,
+ .reset = irqsoff_tracer_reset,
+ .open = irqsoff_tracer_open,
+ .close = irqsoff_tracer_close,
+ .ctrl_update = irqsoff_tracer_ctrl_update,
+ .print_max = 1,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_preemptirqsoff,
+#endif
+};
+
+# define register_preemptirqsoff(trace) register_tracer(&trace)
+#else
+# define register_preemptirqsoff(trace) do { } while (0)
+#endif
+
+__init static int init_irqsoff_tracer(void)
+{
+ register_irqsoff(irqsoff_tracer);
+ register_preemptoff(preemptoff_tracer);
+ register_preemptirqsoff(preemptirqsoff_tracer);
+
+ return 0;
+}
+device_initcall(init_irqsoff_tracer);
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
new file mode 100644
index 00000000000..b13dc19dcbb
--- /dev/null
+++ b/kernel/trace/trace_mmiotrace.c
@@ -0,0 +1,295 @@
+/*
+ * Memory mapped I/O tracing
+ *
+ * Copyright (C) 2008 Pekka Paalanen <pq@iki.fi>
+ */
+
+#define DEBUG 1
+
+#include <linux/kernel.h>
+#include <linux/mmiotrace.h>
+#include <linux/pci.h>
+
+#include "trace.h"
+
+struct header_iter {
+ struct pci_dev *dev;
+};
+
+static struct trace_array *mmio_trace_array;
+static bool overrun_detected;
+
+static void mmio_reset_data(struct trace_array *tr)
+{
+ int cpu;
+
+ overrun_detected = false;
+ tr->time_start = ftrace_now(tr->cpu);
+
+ for_each_online_cpu(cpu)
+ tracing_reset(tr->data[cpu]);
+}
+
+static void mmio_trace_init(struct trace_array *tr)
+{
+ pr_debug("in %s\n", __func__);
+ mmio_trace_array = tr;
+ if (tr->ctrl) {
+ mmio_reset_data(tr);
+ enable_mmiotrace();
+ }
+}
+
+static void mmio_trace_reset(struct trace_array *tr)
+{
+ pr_debug("in %s\n", __func__);
+ if (tr->ctrl)
+ disable_mmiotrace();
+ mmio_reset_data(tr);
+ mmio_trace_array = NULL;
+}
+
+static void mmio_trace_ctrl_update(struct trace_array *tr)
+{
+ pr_debug("in %s\n", __func__);
+ if (tr->ctrl) {
+ mmio_reset_data(tr);
+ enable_mmiotrace();
+ } else {
+ disable_mmiotrace();
+ }
+}
+
+static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
+{
+ int ret = 0;
+ int i;
+ resource_size_t start, end;
+ const struct pci_driver *drv = pci_dev_driver(dev);
+
+ /* XXX: incomplete checks for trace_seq_printf() return value */
+ ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
+ dev->bus->number, dev->devfn,
+ dev->vendor, dev->device, dev->irq);
+ /*
+ * XXX: is pci_resource_to_user() appropriate, since we are
+ * supposed to interpret the __ioremap() phys_addr argument based on
+ * these printed values?
+ */
+ for (i = 0; i < 7; i++) {
+ pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
+ ret += trace_seq_printf(s, " %llx",
+ (unsigned long long)(start |
+ (dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
+ }
+ for (i = 0; i < 7; i++) {
+ pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
+ ret += trace_seq_printf(s, " %llx",
+ dev->resource[i].start < dev->resource[i].end ?
+ (unsigned long long)(end - start) + 1 : 0);
+ }
+ if (drv)
+ ret += trace_seq_printf(s, " %s\n", drv->name);
+ else
+ ret += trace_seq_printf(s, " \n");
+ return ret;
+}
+
+static void destroy_header_iter(struct header_iter *hiter)
+{
+ if (!hiter)
+ return;
+ pci_dev_put(hiter->dev);
+ kfree(hiter);
+}
+
+static void mmio_pipe_open(struct trace_iterator *iter)
+{
+ struct header_iter *hiter;
+ struct trace_seq *s = &iter->seq;
+
+ trace_seq_printf(s, "VERSION 20070824\n");
+
+ hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
+ if (!hiter)
+ return;
+
+ hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
+ iter->private = hiter;
+}
+
+/* XXX: This is not called when the pipe is closed! */
+static void mmio_close(struct trace_iterator *iter)
+{
+ struct header_iter *hiter = iter->private;
+ destroy_header_iter(hiter);
+ iter->private = NULL;
+}
+
+static unsigned long count_overruns(struct trace_iterator *iter)
+{
+ int cpu;
+ unsigned long cnt = 0;
+ for_each_online_cpu(cpu) {
+ cnt += iter->overrun[cpu];
+ iter->overrun[cpu] = 0;
+ }
+ return cnt;
+}
+
+static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
+ char __user *ubuf, size_t cnt, loff_t *ppos)
+{
+ ssize_t ret;
+ struct header_iter *hiter = iter->private;
+ struct trace_seq *s = &iter->seq;
+ unsigned long n;
+
+ n = count_overruns(iter);
+ if (n) {
+ /* XXX: This is later than where events were lost. */
+ trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
+ if (!overrun_detected)
+ pr_warning("mmiotrace has lost events.\n");
+ overrun_detected = true;
+ goto print_out;
+ }
+
+ if (!hiter)
+ return 0;
+
+ mmio_print_pcidev(s, hiter->dev);
+ hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
+
+ if (!hiter->dev) {
+ destroy_header_iter(hiter);
+ iter->private = NULL;
+ }
+
+print_out:
+ ret = trace_seq_to_user(s, ubuf, cnt);
+ return (ret == -EBUSY) ? 0 : ret;
+}
+
+static int mmio_print_rw(struct trace_iterator *iter)
+{
+ struct trace_entry *entry = iter->ent;
+ struct mmiotrace_rw *rw = &entry->mmiorw;
+ struct trace_seq *s = &iter->seq;
+ unsigned long long t = ns2usecs(entry->t);
+ unsigned long usec_rem = do_div(t, 1000000ULL);
+ unsigned secs = (unsigned long)t;
+ int ret = 1;
+
+ switch (entry->mmiorw.opcode) {
+ case MMIO_READ:
+ ret = trace_seq_printf(s,
+ "R %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
+ rw->width, secs, usec_rem, rw->map_id,
+ (unsigned long long)rw->phys,
+ rw->value, rw->pc, 0);
+ break;
+ case MMIO_WRITE:
+ ret = trace_seq_printf(s,
+ "W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
+ rw->width, secs, usec_rem, rw->map_id,
+ (unsigned long long)rw->phys,
+ rw->value, rw->pc, 0);
+ break;
+ case MMIO_UNKNOWN_OP:
+ ret = trace_seq_printf(s,
+ "UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
+ secs, usec_rem, rw->map_id,
+ (unsigned long long)rw->phys,
+ (rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
+ (rw->value >> 0) & 0xff, rw->pc, 0);
+ break;
+ default:
+ ret = trace_seq_printf(s, "rw what?\n");
+ break;
+ }
+ if (ret)
+ return 1;
+ return 0;
+}
+
+static int mmio_print_map(struct trace_iterator *iter)
+{
+ struct trace_entry *entry = iter->ent;
+ struct mmiotrace_map *m = &entry->mmiomap;
+ struct trace_seq *s = &iter->seq;
+ unsigned long long t = ns2usecs(entry->t);
+ unsigned long usec_rem = do_div(t, 1000000ULL);
+ unsigned secs = (unsigned long)t;
+ int ret = 1;
+
+ switch (entry->mmiorw.opcode) {
+ case MMIO_PROBE:
+ ret = trace_seq_printf(s,
+ "MAP %lu.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
+ secs, usec_rem, m->map_id,
+ (unsigned long long)m->phys, m->virt, m->len,
+ 0UL, 0);
+ break;
+ case MMIO_UNPROBE:
+ ret = trace_seq_printf(s,
+ "UNMAP %lu.%06lu %d 0x%lx %d\n",
+ secs, usec_rem, m->map_id, 0UL, 0);
+ break;
+ default:
+ ret = trace_seq_printf(s, "map what?\n");
+ break;
+ }
+ if (ret)
+ return 1;
+ return 0;
+}
+
+/* return 0 to abort printing without consuming current entry in pipe mode */
+static int mmio_print_line(struct trace_iterator *iter)
+{
+ switch (iter->ent->type) {
+ case TRACE_MMIO_RW:
+ return mmio_print_rw(iter);
+ case TRACE_MMIO_MAP:
+ return mmio_print_map(iter);
+ default:
+ return 1; /* ignore unknown entries */
+ }
+}
+
+static struct tracer mmio_tracer __read_mostly =
+{
+ .name = "mmiotrace",
+ .init = mmio_trace_init,
+ .reset = mmio_trace_reset,
+ .pipe_open = mmio_pipe_open,
+ .close = mmio_close,
+ .read = mmio_read,
+ .ctrl_update = mmio_trace_ctrl_update,
+ .print_line = mmio_print_line,
+};
+
+__init static int init_mmio_trace(void)
+{
+ return register_tracer(&mmio_tracer);
+}
+device_initcall(init_mmio_trace);
+
+void mmio_trace_rw(struct mmiotrace_rw *rw)
+{
+ struct trace_array *tr = mmio_trace_array;
+ struct trace_array_cpu *data = tr->data[smp_processor_id()];
+ __trace_mmiotrace_rw(tr, data, rw);
+}
+
+void mmio_trace_mapping(struct mmiotrace_map *map)
+{
+ struct trace_array *tr = mmio_trace_array;
+ struct trace_array_cpu *data;
+
+ preempt_disable();
+ data = tr->data[smp_processor_id()];
+ __trace_mmiotrace_map(tr, data, map);
+ preempt_enable();
+}
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
new file mode 100644
index 00000000000..cb817a209aa
--- /dev/null
+++ b/kernel/trace/trace_sched_switch.c
@@ -0,0 +1,286 @@
+/*
+ * trace context switch
+ *
+ * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/marker.h>
+#include <linux/ftrace.h>
+
+#include "trace.h"
+
+static struct trace_array *ctx_trace;
+static int __read_mostly tracer_enabled;
+static atomic_t sched_ref;
+
+static void
+sched_switch_func(void *private, void *__rq, struct task_struct *prev,
+ struct task_struct *next)
+{
+ struct trace_array **ptr = private;
+ struct trace_array *tr = *ptr;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ tracing_record_cmdline(prev);
+ tracing_record_cmdline(next);
+
+ if (!tracer_enabled)
+ return;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1))
+ tracing_sched_switch_trace(tr, data, prev, next, flags);
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
+static notrace void
+sched_switch_callback(void *probe_data, void *call_data,
+ const char *format, va_list *args)
+{
+ struct task_struct *prev;
+ struct task_struct *next;
+ struct rq *__rq;
+
+ if (!atomic_read(&sched_ref))
+ return;
+
+ /* skip prev_pid %d next_pid %d prev_state %ld */
+ (void)va_arg(*args, int);
+ (void)va_arg(*args, int);
+ (void)va_arg(*args, long);
+ __rq = va_arg(*args, typeof(__rq));
+ prev = va_arg(*args, typeof(prev));
+ next = va_arg(*args, typeof(next));
+
+ /*
+ * If tracer_switch_func only points to the local
+ * switch func, it still needs the ptr passed to it.
+ */
+ sched_switch_func(probe_data, __rq, prev, next);
+}
+
+static void
+wakeup_func(void *private, void *__rq, struct task_struct *wakee, struct
+ task_struct *curr)
+{
+ struct trace_array **ptr = private;
+ struct trace_array *tr = *ptr;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ if (!tracer_enabled)
+ return;
+
+ tracing_record_cmdline(curr);
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+
+ if (likely(disabled == 1))
+ tracing_sched_wakeup_trace(tr, data, wakee, curr, flags);
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
+static notrace void
+wake_up_callback(void *probe_data, void *call_data,
+ const char *format, va_list *args)
+{
+ struct task_struct *curr;
+ struct task_struct *task;
+ struct rq *__rq;
+
+ if (likely(!tracer_enabled))
+ return;
+
+ /* Skip pid %d state %ld */
+ (void)va_arg(*args, int);
+ (void)va_arg(*args, long);
+ /* now get the meat: "rq %p task %p rq->curr %p" */
+ __rq = va_arg(*args, typeof(__rq));
+ task = va_arg(*args, typeof(task));
+ curr = va_arg(*args, typeof(curr));
+
+ tracing_record_cmdline(task);
+ tracing_record_cmdline(curr);
+
+ wakeup_func(probe_data, __rq, task, curr);
+}
+
+static void sched_switch_reset(struct trace_array *tr)
+{
+ int cpu;
+
+ tr->time_start = ftrace_now(tr->cpu);
+
+ for_each_online_cpu(cpu)
+ tracing_reset(tr->data[cpu]);
+}
+
+static int tracing_sched_register(void)
+{
+ int ret;
+
+ ret = marker_probe_register("kernel_sched_wakeup",
+ "pid %d state %ld ## rq %p task %p rq->curr %p",
+ wake_up_callback,
+ &ctx_trace);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't add marker"
+ " probe to kernel_sched_wakeup\n");
+ return ret;
+ }
+
+ ret = marker_probe_register("kernel_sched_wakeup_new",
+ "pid %d state %ld ## rq %p task %p rq->curr %p",
+ wake_up_callback,
+ &ctx_trace);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't add marker"
+ " probe to kernel_sched_wakeup_new\n");
+ goto fail_deprobe;
+ }
+
+ ret = marker_probe_register("kernel_sched_schedule",
+ "prev_pid %d next_pid %d prev_state %ld "
+ "## rq %p prev %p next %p",
+ sched_switch_callback,
+ &ctx_trace);
+ if (ret) {
+ pr_info("sched trace: Couldn't add marker"
+ " probe to kernel_sched_schedule\n");
+ goto fail_deprobe_wake_new;
+ }
+
+ return ret;
+fail_deprobe_wake_new:
+ marker_probe_unregister("kernel_sched_wakeup_new",
+ wake_up_callback,
+ &ctx_trace);
+fail_deprobe:
+ marker_probe_unregister("kernel_sched_wakeup",
+ wake_up_callback,
+ &ctx_trace);
+ return ret;
+}
+
+static void tracing_sched_unregister(void)
+{
+ marker_probe_unregister("kernel_sched_schedule",
+ sched_switch_callback,
+ &ctx_trace);
+ marker_probe_unregister("kernel_sched_wakeup_new",
+ wake_up_callback,
+ &ctx_trace);
+ marker_probe_unregister("kernel_sched_wakeup",
+ wake_up_callback,
+ &ctx_trace);
+}
+
+static void tracing_start_sched_switch(void)
+{
+ long ref;
+
+ ref = atomic_inc_return(&sched_ref);
+ if (ref == 1)
+ tracing_sched_register();
+}
+
+static void tracing_stop_sched_switch(void)
+{
+ long ref;
+
+ ref = atomic_dec_and_test(&sched_ref);
+ if (ref)
+ tracing_sched_unregister();
+}
+
+void tracing_start_cmdline_record(void)
+{
+ tracing_start_sched_switch();
+}
+
+void tracing_stop_cmdline_record(void)
+{
+ tracing_stop_sched_switch();
+}
+
+static void start_sched_trace(struct trace_array *tr)
+{
+ sched_switch_reset(tr);
+ tracing_start_cmdline_record();
+ tracer_enabled = 1;
+}
+
+static void stop_sched_trace(struct trace_array *tr)
+{
+ tracer_enabled = 0;
+ tracing_stop_cmdline_record();
+}
+
+static void sched_switch_trace_init(struct trace_array *tr)
+{
+ ctx_trace = tr;
+
+ if (tr->ctrl)
+ start_sched_trace(tr);
+}
+
+static void sched_switch_trace_reset(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ stop_sched_trace(tr);
+}
+
+static void sched_switch_trace_ctrl_update(struct trace_array *tr)
+{
+ /* When starting a new trace, reset the buffers */
+ if (tr->ctrl)
+ start_sched_trace(tr);
+ else
+ stop_sched_trace(tr);
+}
+
+static struct tracer sched_switch_trace __read_mostly =
+{
+ .name = "sched_switch",
+ .init = sched_switch_trace_init,
+ .reset = sched_switch_trace_reset,
+ .ctrl_update = sched_switch_trace_ctrl_update,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_sched_switch,
+#endif
+};
+
+__init static int init_sched_switch_trace(void)
+{
+ int ret = 0;
+
+ if (atomic_read(&sched_ref))
+ ret = tracing_sched_register();
+ if (ret) {
+ pr_info("error registering scheduler trace\n");
+ return ret;
+ }
+ return register_tracer(&sched_switch_trace);
+}
+device_initcall(init_sched_switch_trace);
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
new file mode 100644
index 00000000000..3c8d61df447
--- /dev/null
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -0,0 +1,448 @@
+/*
+ * trace task wakeup timings
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ * Based on code from the latency_tracer, that is:
+ *
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 William Lee Irwin III
+ */
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/debugfs.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/marker.h>
+
+#include "trace.h"
+
+static struct trace_array *wakeup_trace;
+static int __read_mostly tracer_enabled;
+
+static struct task_struct *wakeup_task;
+static int wakeup_cpu;
+static unsigned wakeup_prio = -1;
+
+static DEFINE_SPINLOCK(wakeup_lock);
+
+static void __wakeup_reset(struct trace_array *tr);
+
+#ifdef CONFIG_FTRACE
+/*
+ * irqsoff uses its own tracer function to keep the overhead down:
+ */
+static void
+wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
+{
+ struct trace_array *tr = wakeup_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int resched;
+ int cpu;
+
+ if (likely(!wakeup_task))
+ return;
+
+ resched = need_resched();
+ preempt_disable_notrace();
+
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (unlikely(disabled != 1))
+ goto out;
+
+ spin_lock_irqsave(&wakeup_lock, flags);
+
+ if (unlikely(!wakeup_task))
+ goto unlock;
+
+ /*
+ * The task can't disappear because it needs to
+ * wake up first, and we have the wakeup_lock.
+ */
+ if (task_cpu(wakeup_task) != cpu)
+ goto unlock;
+
+ trace_function(tr, data, ip, parent_ip, flags);
+
+ unlock:
+ spin_unlock_irqrestore(&wakeup_lock, flags);
+
+ out:
+ atomic_dec(&data->disabled);
+
+ /*
+ * To prevent recursion from the scheduler, if the
+ * resched flag was set before we entered, then
+ * don't reschedule.
+ */
+ if (resched)
+ preempt_enable_no_resched_notrace();
+ else
+ preempt_enable_notrace();
+}
+
+static struct ftrace_ops trace_ops __read_mostly =
+{
+ .func = wakeup_tracer_call,
+};
+#endif /* CONFIG_FTRACE */
+
+/*
+ * Should this new latency be reported/recorded?
+ */
+static int report_latency(cycle_t delta)
+{
+ if (tracing_thresh) {
+ if (delta < tracing_thresh)
+ return 0;
+ } else {
+ if (delta <= tracing_max_latency)
+ return 0;
+ }
+ return 1;
+}
+
+static void notrace
+wakeup_sched_switch(void *private, void *rq, struct task_struct *prev,
+ struct task_struct *next)
+{
+ unsigned long latency = 0, t0 = 0, t1 = 0;
+ struct trace_array **ptr = private;
+ struct trace_array *tr = *ptr;
+ struct trace_array_cpu *data;
+ cycle_t T0, T1, delta;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+
+ if (unlikely(!tracer_enabled))
+ return;
+
+ /*
+ * When we start a new trace, we set wakeup_task to NULL
+ * and then set tracer_enabled = 1. We want to make sure
+ * that another CPU does not see the tracer_enabled = 1
+ * and the wakeup_task with an older task, that might
+ * actually be the same as next.
+ */
+ smp_rmb();
+
+ if (next != wakeup_task)
+ return;
+
+ /* The task we are waiting for is waking up */
+ data = tr->data[wakeup_cpu];
+
+ /* disable local data, not wakeup_cpu data */
+ cpu = raw_smp_processor_id();
+ disabled = atomic_inc_return(&tr->data[cpu]->disabled);
+ if (likely(disabled != 1))
+ goto out;
+
+ spin_lock_irqsave(&wakeup_lock, flags);
+
+ /* We could race with grabbing wakeup_lock */
+ if (unlikely(!tracer_enabled || next != wakeup_task))
+ goto out_unlock;
+
+ trace_function(tr, data, CALLER_ADDR1, CALLER_ADDR2, flags);
+
+ /*
+ * usecs conversion is slow so we try to delay the conversion
+ * as long as possible:
+ */
+ T0 = data->preempt_timestamp;
+ T1 = ftrace_now(cpu);
+ delta = T1-T0;
+
+ if (!report_latency(delta))
+ goto out_unlock;
+
+ latency = nsecs_to_usecs(delta);
+
+ tracing_max_latency = delta;
+ t0 = nsecs_to_usecs(T0);
+ t1 = nsecs_to_usecs(T1);
+
+ update_max_tr(tr, wakeup_task, wakeup_cpu);
+
+out_unlock:
+ __wakeup_reset(tr);
+ spin_unlock_irqrestore(&wakeup_lock, flags);
+out:
+ atomic_dec(&tr->data[cpu]->disabled);
+}
+
+static notrace void
+sched_switch_callback(void *probe_data, void *call_data,
+ const char *format, va_list *args)
+{
+ struct task_struct *prev;
+ struct task_struct *next;
+ struct rq *__rq;
+
+ /* skip prev_pid %d next_pid %d prev_state %ld */
+ (void)va_arg(*args, int);
+ (void)va_arg(*args, int);
+ (void)va_arg(*args, long);
+ __rq = va_arg(*args, typeof(__rq));
+ prev = va_arg(*args, typeof(prev));
+ next = va_arg(*args, typeof(next));
+
+ tracing_record_cmdline(prev);
+
+ /*
+ * If tracer_switch_func only points to the local
+ * switch func, it still needs the ptr passed to it.
+ */
+ wakeup_sched_switch(probe_data, __rq, prev, next);
+}
+
+static void __wakeup_reset(struct trace_array *tr)
+{
+ struct trace_array_cpu *data;
+ int cpu;
+
+ assert_spin_locked(&wakeup_lock);
+
+ for_each_possible_cpu(cpu) {
+ data = tr->data[cpu];
+ tracing_reset(data);
+ }
+
+ wakeup_cpu = -1;
+ wakeup_prio = -1;
+
+ if (wakeup_task)
+ put_task_struct(wakeup_task);
+
+ wakeup_task = NULL;
+}
+
+static void wakeup_reset(struct trace_array *tr)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&wakeup_lock, flags);
+ __wakeup_reset(tr);
+ spin_unlock_irqrestore(&wakeup_lock, flags);
+}
+
+static void
+wakeup_check_start(struct trace_array *tr, struct task_struct *p,
+ struct task_struct *curr)
+{
+ int cpu = smp_processor_id();
+ unsigned long flags;
+ long disabled;
+
+ if (likely(!rt_task(p)) ||
+ p->prio >= wakeup_prio ||
+ p->prio >= curr->prio)
+ return;
+
+ disabled = atomic_inc_return(&tr->data[cpu]->disabled);
+ if (unlikely(disabled != 1))
+ goto out;
+
+ /* interrupts should be off from try_to_wake_up */
+ spin_lock(&wakeup_lock);
+
+ /* check for races. */
+ if (!tracer_enabled || p->prio >= wakeup_prio)
+ goto out_locked;
+
+ /* reset the trace */
+ __wakeup_reset(tr);
+
+ wakeup_cpu = task_cpu(p);
+ wakeup_prio = p->prio;
+
+ wakeup_task = p;
+ get_task_struct(wakeup_task);
+
+ local_save_flags(flags);
+
+ tr->data[wakeup_cpu]->preempt_timestamp = ftrace_now(cpu);
+ trace_function(tr, tr->data[wakeup_cpu],
+ CALLER_ADDR1, CALLER_ADDR2, flags);
+
+out_locked:
+ spin_unlock(&wakeup_lock);
+out:
+ atomic_dec(&tr->data[cpu]->disabled);
+}
+
+static notrace void
+wake_up_callback(void *probe_data, void *call_data,
+ const char *format, va_list *args)
+{
+ struct trace_array **ptr = probe_data;
+ struct trace_array *tr = *ptr;
+ struct task_struct *curr;
+ struct task_struct *task;
+ struct rq *__rq;
+
+ if (likely(!tracer_enabled))
+ return;
+
+ /* Skip pid %d state %ld */
+ (void)va_arg(*args, int);
+ (void)va_arg(*args, long);
+ /* now get the meat: "rq %p task %p rq->curr %p" */
+ __rq = va_arg(*args, typeof(__rq));
+ task = va_arg(*args, typeof(task));
+ curr = va_arg(*args, typeof(curr));
+
+ tracing_record_cmdline(task);
+ tracing_record_cmdline(curr);
+
+ wakeup_check_start(tr, task, curr);
+}
+
+static void start_wakeup_tracer(struct trace_array *tr)
+{
+ int ret;
+
+ ret = marker_probe_register("kernel_sched_wakeup",
+ "pid %d state %ld ## rq %p task %p rq->curr %p",
+ wake_up_callback,
+ &wakeup_trace);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't add marker"
+ " probe to kernel_sched_wakeup\n");
+ return;
+ }
+
+ ret = marker_probe_register("kernel_sched_wakeup_new",
+ "pid %d state %ld ## rq %p task %p rq->curr %p",
+ wake_up_callback,
+ &wakeup_trace);
+ if (ret) {
+ pr_info("wakeup trace: Couldn't add marker"
+ " probe to kernel_sched_wakeup_new\n");
+ goto fail_deprobe;
+ }
+
+ ret = marker_probe_register("kernel_sched_schedule",
+ "prev_pid %d next_pid %d prev_state %ld "
+ "## rq %p prev %p next %p",
+ sched_switch_callback,
+ &wakeup_trace);
+ if (ret) {
+ pr_info("sched trace: Couldn't add marker"
+ " probe to kernel_sched_schedule\n");
+ goto fail_deprobe_wake_new;
+ }
+
+ wakeup_reset(tr);
+
+ /*
+ * Don't let the tracer_enabled = 1 show up before
+ * the wakeup_task is reset. This may be overkill since
+ * wakeup_reset does a spin_unlock after setting the
+ * wakeup_task to NULL, but I want to be safe.
+ * This is a slow path anyway.
+ */
+ smp_wmb();
+
+ register_ftrace_function(&trace_ops);
+
+ tracer_enabled = 1;
+
+ return;
+fail_deprobe_wake_new:
+ marker_probe_unregister("kernel_sched_wakeup_new",
+ wake_up_callback,
+ &wakeup_trace);
+fail_deprobe:
+ marker_probe_unregister("kernel_sched_wakeup",
+ wake_up_callback,
+ &wakeup_trace);
+}
+
+static void stop_wakeup_tracer(struct trace_array *tr)
+{
+ tracer_enabled = 0;
+ unregister_ftrace_function(&trace_ops);
+ marker_probe_unregister("kernel_sched_schedule",
+ sched_switch_callback,
+ &wakeup_trace);
+ marker_probe_unregister("kernel_sched_wakeup_new",
+ wake_up_callback,
+ &wakeup_trace);
+ marker_probe_unregister("kernel_sched_wakeup",
+ wake_up_callback,
+ &wakeup_trace);
+}
+
+static void wakeup_tracer_init(struct trace_array *tr)
+{
+ wakeup_trace = tr;
+
+ if (tr->ctrl)
+ start_wakeup_tracer(tr);
+}
+
+static void wakeup_tracer_reset(struct trace_array *tr)
+{
+ if (tr->ctrl) {
+ stop_wakeup_tracer(tr);
+ /* make sure we put back any tasks we are tracing */
+ wakeup_reset(tr);
+ }
+}
+
+static void wakeup_tracer_ctrl_update(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ start_wakeup_tracer(tr);
+ else
+ stop_wakeup_tracer(tr);
+}
+
+static void wakeup_tracer_open(struct trace_iterator *iter)
+{
+ /* stop the trace while dumping */
+ if (iter->tr->ctrl)
+ stop_wakeup_tracer(iter->tr);
+}
+
+static void wakeup_tracer_close(struct trace_iterator *iter)
+{
+ /* forget about any processes we were recording */
+ if (iter->tr->ctrl)
+ start_wakeup_tracer(iter->tr);
+}
+
+static struct tracer wakeup_tracer __read_mostly =
+{
+ .name = "wakeup",
+ .init = wakeup_tracer_init,
+ .reset = wakeup_tracer_reset,
+ .open = wakeup_tracer_open,
+ .close = wakeup_tracer_close,
+ .ctrl_update = wakeup_tracer_ctrl_update,
+ .print_max = 1,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_wakeup,
+#endif
+};
+
+__init static int init_wakeup_tracer(void)
+{
+ int ret;
+
+ ret = register_tracer(&wakeup_tracer);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+device_initcall(init_wakeup_tracer);
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
new file mode 100644
index 00000000000..0911b7e073b
--- /dev/null
+++ b/kernel/trace/trace_selftest.c
@@ -0,0 +1,563 @@
+/* Include in trace.c */
+
+#include <linux/kthread.h>
+#include <linux/delay.h>
+
+static inline int trace_valid_entry(struct trace_entry *entry)
+{
+ switch (entry->type) {
+ case TRACE_FN:
+ case TRACE_CTX:
+ case TRACE_WAKE:
+ case TRACE_STACK:
+ case TRACE_SPECIAL:
+ return 1;
+ }
+ return 0;
+}
+
+static int
+trace_test_buffer_cpu(struct trace_array *tr, struct trace_array_cpu *data)
+{
+ struct trace_entry *entries;
+ struct page *page;
+ int idx = 0;
+ int i;
+
+ BUG_ON(list_empty(&data->trace_pages));
+ page = list_entry(data->trace_pages.next, struct page, lru);
+ entries = page_address(page);
+
+ check_pages(data);
+ if (head_page(data) != entries)
+ goto failed;
+
+ /*
+ * The starting trace buffer always has valid elements,
+ * if any element exists.
+ */
+ entries = head_page(data);
+
+ for (i = 0; i < tr->entries; i++) {
+
+ if (i < data->trace_idx && !trace_valid_entry(&entries[idx])) {
+ printk(KERN_CONT ".. invalid entry %d ",
+ entries[idx].type);
+ goto failed;
+ }
+
+ idx++;
+ if (idx >= ENTRIES_PER_PAGE) {
+ page = virt_to_page(entries);
+ if (page->lru.next == &data->trace_pages) {
+ if (i != tr->entries - 1) {
+ printk(KERN_CONT ".. entries buffer mismatch");
+ goto failed;
+ }
+ } else {
+ page = list_entry(page->lru.next, struct page, lru);
+ entries = page_address(page);
+ }
+ idx = 0;
+ }
+ }
+
+ page = virt_to_page(entries);
+ if (page->lru.next != &data->trace_pages) {
+ printk(KERN_CONT ".. too many entries");
+ goto failed;
+ }
+
+ return 0;
+
+ failed:
+ /* disable tracing */
+ tracing_disabled = 1;
+ printk(KERN_CONT ".. corrupted trace buffer .. ");
+ return -1;
+}
+
+/*
+ * Test the trace buffer to see if all the elements
+ * are still sane.
+ */
+static int trace_test_buffer(struct trace_array *tr, unsigned long *count)
+{
+ unsigned long flags, cnt = 0;
+ int cpu, ret = 0;
+
+ /* Don't allow flipping of max traces now */
+ raw_local_irq_save(flags);
+ __raw_spin_lock(&ftrace_max_lock);
+ for_each_possible_cpu(cpu) {
+ if (!head_page(tr->data[cpu]))
+ continue;
+
+ cnt += tr->data[cpu]->trace_idx;
+
+ ret = trace_test_buffer_cpu(tr, tr->data[cpu]);
+ if (ret)
+ break;
+ }
+ __raw_spin_unlock(&ftrace_max_lock);
+ raw_local_irq_restore(flags);
+
+ if (count)
+ *count = cnt;
+
+ return ret;
+}
+
+#ifdef CONFIG_FTRACE
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+#define __STR(x) #x
+#define STR(x) __STR(x)
+
+/* Test dynamic code modification and ftrace filters */
+int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
+ struct trace_array *tr,
+ int (*func)(void))
+{
+ unsigned long count;
+ int ret;
+ int save_ftrace_enabled = ftrace_enabled;
+ int save_tracer_enabled = tracer_enabled;
+ char *func_name;
+
+ /* The ftrace test PASSED */
+ printk(KERN_CONT "PASSED\n");
+ pr_info("Testing dynamic ftrace: ");
+
+ /* enable tracing, and record the filter function */
+ ftrace_enabled = 1;
+ tracer_enabled = 1;
+
+ /* passed in by parameter to fool gcc from optimizing */
+ func();
+
+ /* update the records */
+ ret = ftrace_force_update();
+ if (ret) {
+ printk(KERN_CONT ".. ftraced failed .. ");
+ return ret;
+ }
+
+ /*
+ * Some archs *cough*PowerPC*cough* add charachters to the
+ * start of the function names. We simply put a '*' to
+ * accomodate them.
+ */
+ func_name = "*" STR(DYN_FTRACE_TEST_NAME);
+
+ /* filter only on our function */
+ ftrace_set_filter(func_name, strlen(func_name), 1);
+
+ /* enable tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* Sleep for a 1/10 of a second */
+ msleep(100);
+
+ /* we should have nothing in the buffer */
+ ret = trace_test_buffer(tr, &count);
+ if (ret)
+ goto out;
+
+ if (count) {
+ ret = -1;
+ printk(KERN_CONT ".. filter did not filter .. ");
+ goto out;
+ }
+
+ /* call our function again */
+ func();
+
+ /* sleep again */
+ msleep(100);
+
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ ftrace_enabled = 0;
+
+ /* check the trace buffer */
+ ret = trace_test_buffer(tr, &count);
+ trace->reset(tr);
+
+ /* we should only have one item */
+ if (!ret && count != 1) {
+ printk(KERN_CONT ".. filter failed count=%ld ..", count);
+ ret = -1;
+ goto out;
+ }
+ out:
+ ftrace_enabled = save_ftrace_enabled;
+ tracer_enabled = save_tracer_enabled;
+
+ /* Enable tracing on all functions again */
+ ftrace_set_filter(NULL, 0, 1);
+
+ return ret;
+}
+#else
+# define trace_selftest_startup_dynamic_tracing(trace, tr, func) ({ 0; })
+#endif /* CONFIG_DYNAMIC_FTRACE */
+/*
+ * Simple verification test of ftrace function tracer.
+ * Enable ftrace, sleep 1/10 second, and then read the trace
+ * buffer to see if all is in order.
+ */
+int
+trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long count;
+ int ret;
+ int save_ftrace_enabled = ftrace_enabled;
+ int save_tracer_enabled = tracer_enabled;
+
+ /* make sure msleep has been recorded */
+ msleep(1);
+
+ /* force the recorded functions to be traced */
+ ret = ftrace_force_update();
+ if (ret) {
+ printk(KERN_CONT ".. ftraced failed .. ");
+ return ret;
+ }
+
+ /* start the tracing */
+ ftrace_enabled = 1;
+ tracer_enabled = 1;
+
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* Sleep for a 1/10 of a second */
+ msleep(100);
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ ftrace_enabled = 0;
+
+ /* check the trace buffer */
+ ret = trace_test_buffer(tr, &count);
+ trace->reset(tr);
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ goto out;
+ }
+
+ ret = trace_selftest_startup_dynamic_tracing(trace, tr,
+ DYN_FTRACE_TEST_NAME);
+
+ out:
+ ftrace_enabled = save_ftrace_enabled;
+ tracer_enabled = save_tracer_enabled;
+
+ /* kill ftrace totally if we failed */
+ if (ret)
+ ftrace_kill();
+
+ return ret;
+}
+#endif /* CONFIG_FTRACE */
+
+#ifdef CONFIG_IRQSOFF_TRACER
+int
+trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long save_max = tracing_max_latency;
+ unsigned long count;
+ int ret;
+
+ /* start the tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* reset the max latency */
+ tracing_max_latency = 0;
+ /* disable interrupts for a bit */
+ local_irq_disable();
+ udelay(100);
+ local_irq_enable();
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check both trace buffers */
+ ret = trace_test_buffer(tr, NULL);
+ if (!ret)
+ ret = trace_test_buffer(&max_tr, &count);
+ trace->reset(tr);
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
+
+ tracing_max_latency = save_max;
+
+ return ret;
+}
+#endif /* CONFIG_IRQSOFF_TRACER */
+
+#ifdef CONFIG_PREEMPT_TRACER
+int
+trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long save_max = tracing_max_latency;
+ unsigned long count;
+ int ret;
+
+ /* start the tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* reset the max latency */
+ tracing_max_latency = 0;
+ /* disable preemption for a bit */
+ preempt_disable();
+ udelay(100);
+ preempt_enable();
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check both trace buffers */
+ ret = trace_test_buffer(tr, NULL);
+ if (!ret)
+ ret = trace_test_buffer(&max_tr, &count);
+ trace->reset(tr);
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
+
+ tracing_max_latency = save_max;
+
+ return ret;
+}
+#endif /* CONFIG_PREEMPT_TRACER */
+
+#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
+int
+trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long save_max = tracing_max_latency;
+ unsigned long count;
+ int ret;
+
+ /* start the tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+
+ /* reset the max latency */
+ tracing_max_latency = 0;
+
+ /* disable preemption and interrupts for a bit */
+ preempt_disable();
+ local_irq_disable();
+ udelay(100);
+ preempt_enable();
+ /* reverse the order of preempt vs irqs */
+ local_irq_enable();
+
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check both trace buffers */
+ ret = trace_test_buffer(tr, NULL);
+ if (ret)
+ goto out;
+
+ ret = trace_test_buffer(&max_tr, &count);
+ if (ret)
+ goto out;
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ goto out;
+ }
+
+ /* do the test by disabling interrupts first this time */
+ tracing_max_latency = 0;
+ tr->ctrl = 1;
+ trace->ctrl_update(tr);
+ preempt_disable();
+ local_irq_disable();
+ udelay(100);
+ preempt_enable();
+ /* reverse the order of preempt vs irqs */
+ local_irq_enable();
+
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check both trace buffers */
+ ret = trace_test_buffer(tr, NULL);
+ if (ret)
+ goto out;
+
+ ret = trace_test_buffer(&max_tr, &count);
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ goto out;
+ }
+
+ out:
+ trace->reset(tr);
+ tracing_max_latency = save_max;
+
+ return ret;
+}
+#endif /* CONFIG_IRQSOFF_TRACER && CONFIG_PREEMPT_TRACER */
+
+#ifdef CONFIG_SCHED_TRACER
+static int trace_wakeup_test_thread(void *data)
+{
+ /* Make this a RT thread, doesn't need to be too high */
+ struct sched_param param = { .sched_priority = 5 };
+ struct completion *x = data;
+
+ sched_setscheduler(current, SCHED_FIFO, &param);
+
+ /* Make it know we have a new prio */
+ complete(x);
+
+ /* now go to sleep and let the test wake us up */
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule();
+
+ /* we are awake, now wait to disappear */
+ while (!kthread_should_stop()) {
+ /*
+ * This is an RT task, do short sleeps to let
+ * others run.
+ */
+ msleep(100);
+ }
+
+ return 0;
+}
+
+int
+trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long save_max = tracing_max_latency;
+ struct task_struct *p;
+ struct completion isrt;
+ unsigned long count;
+ int ret;
+
+ init_completion(&isrt);
+
+ /* create a high prio thread */
+ p = kthread_run(trace_wakeup_test_thread, &isrt, "ftrace-test");
+ if (IS_ERR(p)) {
+ printk(KERN_CONT "Failed to create ftrace wakeup test thread ");
+ return -1;
+ }
+
+ /* make sure the thread is running at an RT prio */
+ wait_for_completion(&isrt);
+
+ /* start the tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* reset the max latency */
+ tracing_max_latency = 0;
+
+ /* sleep to let the RT thread sleep too */
+ msleep(100);
+
+ /*
+ * Yes this is slightly racy. It is possible that for some
+ * strange reason that the RT thread we created, did not
+ * call schedule for 100ms after doing the completion,
+ * and we do a wakeup on a task that already is awake.
+ * But that is extremely unlikely, and the worst thing that
+ * happens in such a case, is that we disable tracing.
+ * Honestly, if this race does happen something is horrible
+ * wrong with the system.
+ */
+
+ wake_up_process(p);
+
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check both trace buffers */
+ ret = trace_test_buffer(tr, NULL);
+ if (!ret)
+ ret = trace_test_buffer(&max_tr, &count);
+
+
+ trace->reset(tr);
+
+ tracing_max_latency = save_max;
+
+ /* kill the thread */
+ kthread_stop(p);
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
+
+ return ret;
+}
+#endif /* CONFIG_SCHED_TRACER */
+
+#ifdef CONFIG_CONTEXT_SWITCH_TRACER
+int
+trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long count;
+ int ret;
+
+ /* start the tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* Sleep for a 1/10 of a second */
+ msleep(100);
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check the trace buffer */
+ ret = trace_test_buffer(tr, &count);
+ trace->reset(tr);
+
+ if (!ret && !count) {
+ printk(KERN_CONT ".. no entries found ..");
+ ret = -1;
+ }
+
+ return ret;
+}
+#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
+
+#ifdef CONFIG_SYSPROF_TRACER
+int
+trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
+{
+ unsigned long count;
+ int ret;
+
+ /* start the tracing */
+ tr->ctrl = 1;
+ trace->init(tr);
+ /* Sleep for a 1/10 of a second */
+ msleep(100);
+ /* stop the tracing. */
+ tr->ctrl = 0;
+ trace->ctrl_update(tr);
+ /* check the trace buffer */
+ ret = trace_test_buffer(tr, &count);
+ trace->reset(tr);
+
+ return ret;
+}
+#endif /* CONFIG_SYSPROF_TRACER */
diff --git a/kernel/trace/trace_selftest_dynamic.c b/kernel/trace/trace_selftest_dynamic.c
new file mode 100644
index 00000000000..54dd77cce5b
--- /dev/null
+++ b/kernel/trace/trace_selftest_dynamic.c
@@ -0,0 +1,7 @@
+#include "trace.h"
+
+int DYN_FTRACE_TEST_NAME(void)
+{
+ /* used to call mcount */
+ return 0;
+}
diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c
new file mode 100644
index 00000000000..2301e1e7c60
--- /dev/null
+++ b/kernel/trace/trace_sysprof.c
@@ -0,0 +1,363 @@
+/*
+ * trace stack traces
+ *
+ * Copyright (C) 2004-2008, Soeren Sandmann
+ * Copyright (C) 2007 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ */
+#include <linux/kallsyms.h>
+#include <linux/debugfs.h>
+#include <linux/hrtimer.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/fs.h>
+
+#include <asm/stacktrace.h>
+
+#include "trace.h"
+
+static struct trace_array *sysprof_trace;
+static int __read_mostly tracer_enabled;
+
+/*
+ * 1 msec sample interval by default:
+ */
+static unsigned long sample_period = 1000000;
+static const unsigned int sample_max_depth = 512;
+
+static DEFINE_MUTEX(sample_timer_lock);
+/*
+ * Per CPU hrtimers that do the profiling:
+ */
+static DEFINE_PER_CPU(struct hrtimer, stack_trace_hrtimer);
+
+struct stack_frame {
+ const void __user *next_fp;
+ unsigned long return_address;
+};
+
+static int copy_stack_frame(const void __user *fp, struct stack_frame *frame)
+{
+ int ret;
+
+ if (!access_ok(VERIFY_READ, fp, sizeof(*frame)))
+ return 0;
+
+ ret = 1;
+ pagefault_disable();
+ if (__copy_from_user_inatomic(frame, fp, sizeof(*frame)))
+ ret = 0;
+ pagefault_enable();
+
+ return ret;
+}
+
+struct backtrace_info {
+ struct trace_array_cpu *data;
+ struct trace_array *tr;
+ int pos;
+};
+
+static void
+backtrace_warning_symbol(void *data, char *msg, unsigned long symbol)
+{
+ /* Ignore warnings */
+}
+
+static void backtrace_warning(void *data, char *msg)
+{
+ /* Ignore warnings */
+}
+
+static int backtrace_stack(void *data, char *name)
+{
+ /* Don't bother with IRQ stacks for now */
+ return -1;
+}
+
+static void backtrace_address(void *data, unsigned long addr, int reliable)
+{
+ struct backtrace_info *info = data;
+
+ if (info->pos < sample_max_depth && reliable) {
+ __trace_special(info->tr, info->data, 1, addr, 0);
+
+ info->pos++;
+ }
+}
+
+const static struct stacktrace_ops backtrace_ops = {
+ .warning = backtrace_warning,
+ .warning_symbol = backtrace_warning_symbol,
+ .stack = backtrace_stack,
+ .address = backtrace_address,
+};
+
+static int
+trace_kernel(struct pt_regs *regs, struct trace_array *tr,
+ struct trace_array_cpu *data)
+{
+ struct backtrace_info info;
+ unsigned long bp;
+ char *stack;
+
+ info.tr = tr;
+ info.data = data;
+ info.pos = 1;
+
+ __trace_special(info.tr, info.data, 1, regs->ip, 0);
+
+ stack = ((char *)regs + sizeof(struct pt_regs));
+#ifdef CONFIG_FRAME_POINTER
+ bp = regs->bp;
+#else
+ bp = 0;
+#endif
+
+ dump_trace(NULL, regs, (void *)stack, bp, &backtrace_ops, &info);
+
+ return info.pos;
+}
+
+static void timer_notify(struct pt_regs *regs, int cpu)
+{
+ struct trace_array_cpu *data;
+ struct stack_frame frame;
+ struct trace_array *tr;
+ const void __user *fp;
+ int is_user;
+ int i;
+
+ if (!regs)
+ return;
+
+ tr = sysprof_trace;
+ data = tr->data[cpu];
+ is_user = user_mode(regs);
+
+ if (!current || current->pid == 0)
+ return;
+
+ if (is_user && current->state != TASK_RUNNING)
+ return;
+
+ __trace_special(tr, data, 0, 0, current->pid);
+
+ if (!is_user)
+ i = trace_kernel(regs, tr, data);
+ else
+ i = 0;
+
+ /*
+ * Trace user stack if we are not a kernel thread
+ */
+ if (current->mm && i < sample_max_depth) {
+ regs = (struct pt_regs *)current->thread.sp0 - 1;
+
+ fp = (void __user *)regs->bp;
+
+ __trace_special(tr, data, 2, regs->ip, 0);
+
+ while (i < sample_max_depth) {
+ frame.next_fp = 0;
+ frame.return_address = 0;
+ if (!copy_stack_frame(fp, &frame))
+ break;
+ if ((unsigned long)fp < regs->sp)
+ break;
+
+ __trace_special(tr, data, 2, frame.return_address,
+ (unsigned long)fp);
+ fp = frame.next_fp;
+
+ i++;
+ }
+
+ }
+
+ /*
+ * Special trace entry if we overflow the max depth:
+ */
+ if (i == sample_max_depth)
+ __trace_special(tr, data, -1, -1, -1);
+
+ __trace_special(tr, data, 3, current->pid, i);
+}
+
+static enum hrtimer_restart stack_trace_timer_fn(struct hrtimer *hrtimer)
+{
+ /* trace here */
+ timer_notify(get_irq_regs(), smp_processor_id());
+
+ hrtimer_forward_now(hrtimer, ns_to_ktime(sample_period));
+
+ return HRTIMER_RESTART;
+}
+
+static void start_stack_timer(int cpu)
+{
+ struct hrtimer *hrtimer = &per_cpu(stack_trace_hrtimer, cpu);
+
+ hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ hrtimer->function = stack_trace_timer_fn;
+ hrtimer->cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+
+ hrtimer_start(hrtimer, ns_to_ktime(sample_period), HRTIMER_MODE_REL);
+}
+
+static void start_stack_timers(void)
+{
+ cpumask_t saved_mask = current->cpus_allowed;
+ int cpu;
+
+ for_each_online_cpu(cpu) {
+ set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
+ start_stack_timer(cpu);
+ }
+ set_cpus_allowed_ptr(current, &saved_mask);
+}
+
+static void stop_stack_timer(int cpu)
+{
+ struct hrtimer *hrtimer = &per_cpu(stack_trace_hrtimer, cpu);
+
+ hrtimer_cancel(hrtimer);
+}
+
+static void stop_stack_timers(void)
+{
+ int cpu;
+
+ for_each_online_cpu(cpu)
+ stop_stack_timer(cpu);
+}
+
+static void stack_reset(struct trace_array *tr)
+{
+ int cpu;
+
+ tr->time_start = ftrace_now(tr->cpu);
+
+ for_each_online_cpu(cpu)
+ tracing_reset(tr->data[cpu]);
+}
+
+static void start_stack_trace(struct trace_array *tr)
+{
+ mutex_lock(&sample_timer_lock);
+ stack_reset(tr);
+ start_stack_timers();
+ tracer_enabled = 1;
+ mutex_unlock(&sample_timer_lock);
+}
+
+static void stop_stack_trace(struct trace_array *tr)
+{
+ mutex_lock(&sample_timer_lock);
+ stop_stack_timers();
+ tracer_enabled = 0;
+ mutex_unlock(&sample_timer_lock);
+}
+
+static void stack_trace_init(struct trace_array *tr)
+{
+ sysprof_trace = tr;
+
+ if (tr->ctrl)
+ start_stack_trace(tr);
+}
+
+static void stack_trace_reset(struct trace_array *tr)
+{
+ if (tr->ctrl)
+ stop_stack_trace(tr);
+}
+
+static void stack_trace_ctrl_update(struct trace_array *tr)
+{
+ /* When starting a new trace, reset the buffers */
+ if (tr->ctrl)
+ start_stack_trace(tr);
+ else
+ stop_stack_trace(tr);
+}
+
+static struct tracer stack_trace __read_mostly =
+{
+ .name = "sysprof",
+ .init = stack_trace_init,
+ .reset = stack_trace_reset,
+ .ctrl_update = stack_trace_ctrl_update,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_sysprof,
+#endif
+};
+
+__init static int init_stack_trace(void)
+{
+ return register_tracer(&stack_trace);
+}
+device_initcall(init_stack_trace);
+
+#define MAX_LONG_DIGITS 22
+
+static ssize_t
+sysprof_sample_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[MAX_LONG_DIGITS];
+ int r;
+
+ r = sprintf(buf, "%ld\n", nsecs_to_usecs(sample_period));
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+}
+
+static ssize_t
+sysprof_sample_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[MAX_LONG_DIGITS];
+ unsigned long val;
+
+ if (cnt > MAX_LONG_DIGITS-1)
+ cnt = MAX_LONG_DIGITS-1;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ val = simple_strtoul(buf, NULL, 10);
+ /*
+ * Enforce a minimum sample period of 100 usecs:
+ */
+ if (val < 100)
+ val = 100;
+
+ mutex_lock(&sample_timer_lock);
+ stop_stack_timers();
+ sample_period = val * 1000;
+ start_stack_timers();
+ mutex_unlock(&sample_timer_lock);
+
+ return cnt;
+}
+
+static struct file_operations sysprof_sample_fops = {
+ .read = sysprof_sample_read,
+ .write = sysprof_sample_write,
+};
+
+void init_tracer_sysprof_debugfs(struct dentry *d_tracer)
+{
+ struct dentry *entry;
+
+ entry = debugfs_create_file("sysprof_sample_period", 0644,
+ d_tracer, NULL, &sysprof_sample_fops);
+ if (entry)
+ return;
+ pr_warning("Could not create debugfs 'dyn_ftrace_total_info' entry\n");
+}
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 29fc39f1029..ce7799540c9 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -13,7 +13,7 @@
* Kai Petzke <wpp@marie.physik.tu-berlin.de>
* Theodore Ts'o <tytso@mit.edu>
*
- * Made to use alloc_percpu by Christoph Lameter <clameter@sgi.com>.
+ * Made to use alloc_percpu by Christoph Lameter.
*/
#include <linux/module.h>