hrtimer: unlock hrtimer_wakeup

hrtimer_wakeup creates a

  base->lock
    rq->lock

lock dependancy. Avoid this by switching to HRTIMER_CB_IRQSAFE_NO_SOFTIRQ
which doesn't hold base->lock.

This fully untangles hrtimer locks from the scheduler locks, and allows
hrtimer usage in the scheduler proper.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2008-01-25 21:08:32 +01:00 committed by Ingo Molnar
parent d3d74453c3
commit 37bb6cb409

View file

@ -1293,7 +1293,7 @@ void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, struct task_struct *task)
sl->timer.function = hrtimer_wakeup;
sl->task = task;
#ifdef CONFIG_HIGH_RES_TIMERS
sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_RESTART;
sl->timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
#endif
}
@ -1304,6 +1304,8 @@ static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
do {
set_current_state(TASK_INTERRUPTIBLE);
hrtimer_start(&t->timer, t->timer.expires, mode);
if (!hrtimer_active(&t->timer))
t->task = NULL;
if (likely(t->task))
schedule();