static void futex_wait_queue_me(struct futex_hash_bucket *hb, struct futex_q *q,
				struct hrtimer_sleeper *timeout)
{
	/*
	 * The task state is guaranteed to be set before another task can
	 * wake it. set_current_state() is implemented using smp_store_mb() and
	 * queue_me() calls spin_unlock() upon completion, both serializing
	 * access to the hash list and forcing another memory barrier.
	 */
	set_current_state(TASK_INTERRUPTIBLE);
	queue_me(q, hb);

	/* Arm the timer */
	if (timeout)
		hrtimer_start_expires(&timeout->timer, HRTIMER_MODE_ABS);

	/*
	 * If we have been removed from the hash list, then another task
	 * has tried to wake us, and we can skip the call to schedule().
	 */
	if (likely(!plist_node_empty(&q->list))) {
		/*
		 * If the timer has already expired, current will already be
		 * flagged for rescheduling. Only call schedule if there
		 * is no timeout, or if it has yet to expire.
		 */
		if (!timeout || timeout->task)
			freezable_schedule();
	}
	__set_current_state(TASK_RUNNING);
}
Unknown