Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  posix-timers: RCU conversion
This commit is contained in:
Linus Torvalds 2011-05-25 08:58:50 -07:00
commit 19426a8f81
2 changed files with 15 additions and 11 deletions

View File

@ -82,6 +82,7 @@ struct k_itimer {
unsigned long expires;
} mmtimer;
struct alarm alarmtimer;
struct rcu_head rcu;
} it;
};

View File

@ -491,6 +491,13 @@ static struct k_itimer * alloc_posix_timer(void)
return tmr;
}
static void k_itimer_rcu_free(struct rcu_head *head)
{
struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
kmem_cache_free(posix_timers_cache, tmr);
}
#define IT_ID_SET 1
#define IT_ID_NOT_SET 0
static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
@ -503,7 +510,7 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
}
put_pid(tmr->it_pid);
sigqueue_free(tmr->sigq);
kmem_cache_free(posix_timers_cache, tmr);
call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
}
static struct k_clock *clockid_to_kclock(const clockid_t id)
@ -631,22 +638,18 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
static struct k_itimer *__lock_timer(timer_t timer_id, unsigned long *flags)
{
struct k_itimer *timr;
/*
* Watch out here. We do a irqsave on the idr_lock and pass the
* flags part over to the timer lock. Must not let interrupts in
* while we are moving the lock.
*/
spin_lock_irqsave(&idr_lock, *flags);
rcu_read_lock();
timr = idr_find(&posix_timers_id, (int)timer_id);
if (timr) {
spin_lock(&timr->it_lock);
spin_lock_irqsave(&timr->it_lock, *flags);
if (timr->it_signal == current->signal) {
spin_unlock(&idr_lock);
rcu_read_unlock();
return timr;
}
spin_unlock(&timr->it_lock);
spin_unlock_irqrestore(&timr->it_lock, *flags);
}
spin_unlock_irqrestore(&idr_lock, *flags);
rcu_read_unlock();
return NULL;
}