int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
				   struct futex_q *q, union futex_key *key2,
				   struct hrtimer_sleeper *timeout)
{
	int ret = 0;

	/*
	 * With the hb lock held, we avoid races while we process the wakeup.
	 * We only need to hold hb (and not hb2) to ensure atomicity as the
	 * wakeup code can't change q.key from uaddr to uaddr2 if we hold hb.
	 * It can't be requeued from uaddr2 to something else since we don't
	 * support a PI aware source futex for requeue.
	 */
	if (!match_futex(&q->key, key2)) {
		WARN_ON(q->lock_ptr && (&hb->lock != q->lock_ptr));
		/*
		 * We were woken prior to requeue by a timeout or a signal.
		 * Unqueue the futex_q and determine which it was.
		 */
		plist_del(&q->list, &hb->chain);
		hb_waiters_dec(hb);

		/* Handle spurious wakeups gracefully */
		ret = -EWOULDBLOCK;
		if (timeout && !timeout->task)
			ret = -ETIMEDOUT;
		else if (signal_pending(current))
			ret = -ERESTARTNOINTR;
	}
	return ret;
}
Unknown