bool freeze_workqueues_busy(void)
{
	bool busy = false;
	struct workqueue_struct *wq;
	struct pool_workqueue *pwq;

	mutex_lock(&wq_pool_mutex);

	WARN_ON_ONCE(!workqueue_freezing);

	list_for_each_entry(wq, &workqueues, list) {
		if (!(wq->flags & WQ_FREEZABLE))
			continue;
		/*
		 * nr_active is monotonically decreasing.  It's safe
		 * to peek without lock.
		 */
		rcu_read_lock_sched();
		for_each_pwq(pwq, wq) {
			WARN_ON_ONCE(pwq->nr_active < 0);
			if (pwq->nr_active) {
				busy = true;
				rcu_read_unlock_sched();
				goto out_unlock;
			}
		}
		rcu_read_unlock_sched();
	}
out_unlock:
	mutex_unlock(&wq_pool_mutex);
	return busy;
}
Unknown