/* Must be called with the hb lock held.  */
static struct futex_q* futex_top_waiter(struct futex_hash_bucket *hb, union futex_key *key)
/* Must be called with the hb lock held.  */
static struct futex_q* futex_top_waiter(struct futex_hash_bucket *hb, union futex_key *key)
{
	struct futex_q *this;
	plist_for_each_entry(this, &hb->chain, list) {
		if (match_futex(&this->key, key))
			return this;
	}
	return NULL;
}