workqueue: kick a worker in pwq_adjust_max_active()

If pwq_adjust_max_active() changes max_active from 0 to
saved_max_active, it needs to wakeup worker.  This is already done by
thaw_workqueues().

If pwq_adjust_max_active() increases max_active for an unbound wq,
while not strictly necessary for correctness, it's still desirable to
wake up a worker so that the requested concurrency level is reached
sooner.

Move wake_up_worker() call from thaw_workqueues() to
pwq_adjust_max_active() so that it can handle both of the above two
cases.  This also makes thaw_workqueues() simpler.

tj: Updated comments and description.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Lai Jiangshan 2013-03-20 10:52:30 -07:00 коммит произвёл Tejun Heo
Родитель 6a092dfd51
Коммит 951a078a52
1 изменённых файлов: 6 добавлений и 7 удалений

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@ -3598,6 +3598,12 @@ static void pwq_adjust_max_active(struct pool_workqueue *pwq)
while (!list_empty(&pwq->delayed_works) &&
pwq->nr_active < pwq->max_active)
pwq_activate_first_delayed(pwq);
/*
* Need to kick a worker after thawed or an unbound wq's
* max_active is bumped. It's a slow path. Do it always.
*/
wake_up_worker(pwq->pool);
} else {
pwq->max_active = 0;
}
@ -4401,13 +4407,6 @@ void thaw_workqueues(void)
}
spin_unlock_irq(&pwq_lock);
/* kick workers */
for_each_pool(pool, pi) {
spin_lock_irq(&pool->lock);
wake_up_worker(pool);
spin_unlock_irq(&pool->lock);
}
workqueue_freezing = false;
out_unlock:
mutex_unlock(&wq_mutex);