diff options
| author | Oleg Nesterov <oleg@tv-sign.ru> | 2006-10-28 10:38:51 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-28 11:30:54 -0700 |
| commit | 093a8e8aecd77b2799934996a55a6838e1e2b8f3 (patch) | |
| tree | ece87b2e194494059b2d4aaa43a094786dac1db7 | |
| parent | 05d5bcd60e8202e5c7b28cf61186043a4d612623 (diff) | |
[PATCH] taskstats_tgid_free: fix usage
taskstats_tgid_free() is called on copy_process's error path. This is wrong.
IF (clone_flags & CLONE_THREAD)
We should not clear ->signal->taskstats, current uses it,
it probably has a valid accumulated info.
ELSE
taskstats_tgid_init() set ->signal->taskstats = NULL,
there is nothing to free.
Move the callsite to __exit_signal(). We don't need any locking, entire
thread group is exiting, nobody should have a reference to soon to be
released ->signal.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | include/linux/taskstats_kern.h | 13 | ||||
| -rw-r--r-- | kernel/exit.c | 1 | ||||
| -rw-r--r-- | kernel/fork.c | 1 |
3 files changed, 3 insertions, 12 deletions
diff --git a/include/linux/taskstats_kern.h b/include/linux/taskstats_kern.h index 16894b7edcc8..a437ca0d226b 100644 --- a/include/linux/taskstats_kern.h +++ b/include/linux/taskstats_kern.h @@ -49,17 +49,8 @@ static inline void taskstats_tgid_alloc(struct signal_struct *sig) static inline void taskstats_tgid_free(struct signal_struct *sig) { - struct taskstats *stats = NULL; - unsigned long flags; - - spin_lock_irqsave(&sig->stats_lock, flags); - if (sig->stats) { - stats = sig->stats; - sig->stats = NULL; - } - spin_unlock_irqrestore(&sig->stats_lock, flags); - if (stats) - kmem_cache_free(taskstats_cache, stats); + if (sig->stats) + kmem_cache_free(taskstats_cache, sig->stats); } extern void taskstats_exit_alloc(struct taskstats **, unsigned int *); diff --git a/kernel/exit.c b/kernel/exit.c index f250a5e3e281..06de6c4e8ca3 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -128,6 +128,7 @@ static void __exit_signal(struct task_struct *tsk) flush_sigqueue(&tsk->pending); if (sig) { flush_sigqueue(&sig->shared_pending); + taskstats_tgid_free(sig); __cleanup_signal(sig); } } diff --git a/kernel/fork.c b/kernel/fork.c index 29ebb30850ed..213326609bac 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -897,7 +897,6 @@ static inline int copy_signal(unsigned long clone_flags, struct task_struct * ts void __cleanup_signal(struct signal_struct *sig) { exit_thread_group_keys(sig); - taskstats_tgid_free(sig); kmem_cache_free(signal_cachep, sig); } |