diff options
| author | Oleg Nesterov <oleg@tv-sign.ru> | 2008-12-01 23:18:15 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-12-12 17:00:34 +0100 |
| commit | 899921025b406a71a8aeb2d7855658ea0cf0ed23 (patch) | |
| tree | 6faf12eb15231b6a430d0e1e11a4f6fcc581874e /kernel/posix-timers.c | |
| parent | posix-timers: use "struct pid*" instead of "struct task_struct*" (diff) | |
| download | linux-899921025b406a71a8aeb2d7855658ea0cf0ed23.tar.xz linux-899921025b406a71a8aeb2d7855658ea0cf0ed23.zip | |
posix-timers: check ->it_signal instead of ->it_pid to validate the timer
Impact: clean up, speed up
->it_pid (was ->it_process) has also a special meaning: if it is NULL,
the timer is under deletion or it wasn't initialized yet. We can check
->it_signal != NULL instead, this way we can
- simplify sys_timer_create() a bit
- remove yet another check from lock_timer()
- move put_pid(->it_pid) into release_posix_timer() which
runs outside of ->it_lock
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/posix-timers.c')
| -rw-r--r-- | kernel/posix-timers.c | 17 |
1 files changed, 7 insertions, 10 deletions
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c index 42a39afd694a..aa922bbb6403 100644 --- a/kernel/posix-timers.c +++ b/kernel/posix-timers.c @@ -464,6 +464,7 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set) idr_remove(&posix_timers_id, tmr->it_id); spin_unlock_irqrestore(&idr_lock, flags); } + put_pid(tmr->it_pid); sigqueue_free(tmr->sigq); kmem_cache_free(posix_timers_cache, tmr); } @@ -477,7 +478,6 @@ sys_timer_create(const clockid_t which_clock, { struct k_itimer *new_timer; int error, new_timer_id; - struct pid *it_pid; sigevent_t event; int it_id_set = IT_ID_NOT_SET; @@ -531,9 +531,9 @@ sys_timer_create(const clockid_t which_clock, goto out; } rcu_read_lock(); - it_pid = get_pid(good_sigevent(&event)); + new_timer->it_pid = get_pid(good_sigevent(&event)); rcu_read_unlock(); - if (!it_pid) { + if (!new_timer->it_pid) { error = -EINVAL; goto out; } @@ -541,7 +541,7 @@ sys_timer_create(const clockid_t which_clock, event.sigev_notify = SIGEV_SIGNAL; event.sigev_signo = SIGALRM; event.sigev_value.sival_int = new_timer->it_id; - it_pid = get_pid(task_tgid(current)); + new_timer->it_pid = get_pid(task_tgid(current)); } new_timer->it_sigev_notify = event.sigev_notify; @@ -551,7 +551,6 @@ sys_timer_create(const clockid_t which_clock, new_timer->sigq->info.si_code = SI_TIMER; spin_lock_irq(¤t->sighand->siglock); - new_timer->it_pid = it_pid; new_timer->it_signal = current->signal; list_add(&new_timer->list, ¤t->signal->posix_timers); spin_unlock_irq(¤t->sighand->siglock); @@ -587,7 +586,7 @@ static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags) timr = idr_find(&posix_timers_id, (int)timer_id); if (timr) { spin_lock(&timr->it_lock); - if (timr->it_pid && timr->it_signal == current->signal) { + if (timr->it_signal == current->signal) { spin_unlock(&idr_lock); return timr; } @@ -834,8 +833,7 @@ retry_delete: * This keeps any tasks waiting on the spin lock from thinking * they got something (see the lock code above). */ - put_pid(timer->it_pid); - timer->it_pid = NULL; + timer->it_signal = NULL; unlock_timer(timer, flags); release_posix_timer(timer, IT_ID_SET); @@ -861,8 +859,7 @@ retry_delete: * This keeps any tasks waiting on the spin lock from thinking * they got something (see the lock code above). */ - put_pid(timer->it_pid); - timer->it_pid = NULL; + timer->it_signal = NULL; unlock_timer(timer, flags); release_posix_timer(timer, IT_ID_SET); |