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 --- kernel/hrtimer.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) Index: linux-2.6/kernel/hrtimer.c =================================================================== --- linux-2.6.orig/kernel/hrtimer.c +++ linux-2.6/kernel/hrtimer.c @@ -1296,7 +1296,7 @@ void hrtimer_init_sleeper(struct hrtimer 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 } @@ -1307,6 +1307,8 @@ static int __sched do_nanosleep(struct h 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(); -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/