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From:   qiang.zhang@windriver.com
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Subject: [PATCH] workqueue: Remove rcu_read_lock/unlock() in workqueue_congested()
Date:   Wed, 17 Feb 2021 19:58:02 +0800
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From: Zqiang <qiang.zhang@windriver.com>

The RCU read critical area already by preempt_disable/enable()
(equivalent to rcu_read_lock_sched/unlock_sched()) mark, so remove
rcu_read_lock/unlock().

Signed-off-by: Zqiang <qiang.zhang@windriver.com>
---
 kernel/workqueue.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 0d150da252e8..c599835ad6c3 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -4540,7 +4540,6 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
 	struct pool_workqueue *pwq;
 	bool ret;
 
-	rcu_read_lock();
 	preempt_disable();
 
 	if (cpu == WORK_CPU_UNBOUND)
@@ -4553,7 +4552,6 @@ bool workqueue_congested(int cpu, struct workqueue_struct *wq)
 
 	ret = !list_empty(&pwq->delayed_works);
 	preempt_enable();
-	rcu_read_unlock();
 
 	return ret;
 }
-- 
2.25.1