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>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index d2ac6cb..79d1d34 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -3598,6 +3598,12 @@
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 @@
}
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);