[PATCH 05/21] workqueue: kick workers in pwq_adjust_max_active()

[Lai Jiangshan <laijs@cn.fujitsu.com>]

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

if pwq_adjust_max_active() increase the max_active for unbound wq,
it also needs to wakeup worker. This action is missing.

To make these two cases happy, we move kicking workers code from
thaw_workqueues() to pwq_adjust_max_active().

It also makes thaw_workqueues() simpler.

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
---
 kernel/workqueue.c |   15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 8c882ae..fb81159 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -3600,6 +3600,14 @@ 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 wake up worker in any of these cases:
+		 *	wq is just thawed
+		 *	unbound wq's max_active is just increased
+		 * But this function is slowpath, wake up worker unconditionally
+		 */
+		wake_up_worker(pwq->pool);
 	}
 
 	spin_unlock(&pwq->pool->lock);
@@ -4401,13 +4409,6 @@ 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);
-- 
1.7.7.6