diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/Kconfig | 10 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 23 | ||||
| -rw-r--r-- | kernel/user.c | 67 |
3 files changed, 55 insertions, 45 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 4a13e5a01ce..61071fecc82 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -147,7 +147,7 @@ config IRQSOFF_TRACER disabled by default and can be runtime (re-)started via: - echo 0 > /debugfs/tracing/tracing_max_latency + echo 0 > /sys/kernel/debug/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 @@ -168,7 +168,7 @@ config PREEMPT_TRACER disabled by default and can be runtime (re-)started via: - echo 0 > /debugfs/tracing/tracing_max_latency + echo 0 > /sys/kernel/debug/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 @@ -261,7 +261,7 @@ config PROFILE_ANNOTATED_BRANCHES This tracer profiles all the the likely and unlikely macros in the kernel. It will display the results in: - /debugfs/tracing/profile_annotated_branch + /sys/kernel/debug/tracing/profile_annotated_branch Note: this will add a significant overhead, only turn this on if you need to profile the system's use of these macros. @@ -274,7 +274,7 @@ config PROFILE_ALL_BRANCHES taken in the kernel is recorded whether it hit or miss. The results will be displayed in: - /debugfs/tracing/profile_branch + /sys/kernel/debug/tracing/profile_branch This option also enables the likely/unlikely profiler. @@ -323,7 +323,7 @@ config STACK_TRACER select KALLSYMS help This special tracer records the maximum stack footprint of the - kernel and displays it in debugfs/tracing/stack_trace. + kernel and displays it in /sys/kernel/debug/tracing/stack_trace. This tracer works by hooking into every function call that the kernel executes, and keeping a maximum stack depth value and diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 8acd9b81a5d..c1878bfb2e1 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -344,7 +344,7 @@ static raw_spinlock_t ftrace_max_lock = /* * 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) + * for later retrieval via /sys/kernel/debug/tracing/latency_trace) */ static void __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) @@ -2414,21 +2414,20 @@ static const struct file_operations tracing_iter_fops = { 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" + "# mount -t debugfs nodev /sys/kernel/debug\n\n" + "# cat /sys/kernel/debug/tracing/available_tracers\n" "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" - "# cat /debug/tracing/current_tracer\n" + "# cat /sys/kernel/debug/tracing/current_tracer\n" "nop\n" - "# echo sched_switch > /debug/tracing/current_tracer\n" - "# cat /debug/tracing/current_tracer\n" + "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" + "# cat /sys/kernel/debug/tracing/current_tracer\n" "sched_switch\n" - "# cat /debug/tracing/trace_options\n" + "# cat /sys/kernel/debug/tracing/trace_options\n" "noprint-parent nosym-offset nosym-addr noverbose\n" - "# echo print-parent > /debug/tracing/trace_options\n" - "# echo 1 > /debug/tracing/tracing_enabled\n" - "# cat /debug/tracing/trace > /tmp/trace.txt\n" - "# echo 0 > /debug/tracing/tracing_enabled\n" + "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" + "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" + "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" + "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" ; static ssize_t diff --git a/kernel/user.c b/kernel/user.c index 850e0ba41c1..2c000e7132a 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -75,21 +75,6 @@ static void uid_hash_remove(struct user_struct *up) put_user_ns(up->user_ns); } -static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent) -{ - struct user_struct *user; - struct hlist_node *h; - - hlist_for_each_entry(user, h, hashent, uidhash_node) { - if (user->uid == uid) { - atomic_inc(&user->__count); - return user; - } - } - - return NULL; -} - #ifdef CONFIG_USER_SCHED static void sched_destroy_user(struct user_struct *up) @@ -119,6 +104,23 @@ static int sched_create_user(struct user_struct *up) { return 0; } #if defined(CONFIG_USER_SCHED) && defined(CONFIG_SYSFS) +static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent) +{ + struct user_struct *user; + struct hlist_node *h; + + hlist_for_each_entry(user, h, hashent, uidhash_node) { + if (user->uid == uid) { + /* possibly resurrect an "almost deleted" object */ + if (atomic_inc_return(&user->__count) == 1) + cancel_delayed_work(&user->work); + return user; + } + } + + return NULL; +} + static struct kset *uids_kset; /* represents the /sys/kernel/uids/ directory */ static DEFINE_MUTEX(uids_mutex); @@ -283,12 +285,12 @@ int __init uids_sysfs_init(void) return uids_user_create(&root_user); } -/* work function to remove sysfs directory for a user and free up +/* delayed work function to remove sysfs directory for a user and free up * corresponding structures. */ static void cleanup_user_struct(struct work_struct *w) { - struct user_struct *up = container_of(w, struct user_struct, work); + struct user_struct *up = container_of(w, struct user_struct, work.work); unsigned long flags; int remove_user = 0; @@ -297,15 +299,12 @@ static void cleanup_user_struct(struct work_struct *w) */ uids_mutex_lock(); - local_irq_save(flags); - - if (atomic_dec_and_lock(&up->__count, &uidhash_lock)) { + spin_lock_irqsave(&uidhash_lock, flags); + if (atomic_read(&up->__count) == 0) { uid_hash_remove(up); remove_user = 1; - spin_unlock_irqrestore(&uidhash_lock, flags); - } else { - local_irq_restore(flags); } + spin_unlock_irqrestore(&uidhash_lock, flags); if (!remove_user) goto done; @@ -331,16 +330,28 @@ done: */ static void free_user(struct user_struct *up, unsigned long flags) { - /* restore back the count */ - atomic_inc(&up->__count); spin_unlock_irqrestore(&uidhash_lock, flags); - - INIT_WORK(&up->work, cleanup_user_struct); - schedule_work(&up->work); + INIT_DELAYED_WORK(&up->work, cleanup_user_struct); + schedule_delayed_work(&up->work, msecs_to_jiffies(1000)); } #else /* CONFIG_USER_SCHED && CONFIG_SYSFS */ +static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent) +{ + struct user_struct *user; + struct hlist_node *h; + + hlist_for_each_entry(user, h, hashent, uidhash_node) { + if (user->uid == uid) { + atomic_inc(&user->__count); + return user; + } + } + + return NULL; +} + int uids_sysfs_init(void) { return 0; } static inline int uids_user_create(struct user_struct *up) { return 0; } static inline void uids_mutex_lock(void) { } |