static void put_pi_state(struct futex_pi_state *pi_state)
{
	if (!pi_state)
		return;

	if (!atomic_dec_and_test(&pi_state->refcount))
		return;

	/*
	 * If pi_state->owner is NULL, the owner is most probably dying
	 * and has cleaned up the pi_state already
	 */
	if (pi_state->owner) {
		raw_spin_lock_irq(&pi_state->owner->pi_lock);
		list_del_init(&pi_state->list);
		raw_spin_unlock_irq(&pi_state->owner->pi_lock);

		rt_mutex_proxy_unlock(&pi_state->pi_mutex, pi_state->owner);
	}

	if (current->pi_state_cache)
		kfree(pi_state);
	else {
		/*
		 * pi_state->list is already empty.
		 * clear pi_state->owner.
		 * refcount is at 0 - put it back to 1.
		 */
		pi_state->owner = NULL;
		atomic_set(&pi_state->refcount, 1);
		current->pi_state_cache = pi_state;
	}
}
Unknown