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Sender: Tejun Heo <htejun@gmail.com>
Date: Fri, 26 Jan 2024 11:57:41 -1000
From: Tejun Heo <tj@kernel.org>
To: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH wq/for-6.9] workqueue: Drop unnecessary kick_pool() in
 create_worker()
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From 6a229b0e2ff6143b65ba4ef42bd71e29ffc2c16d Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Fri, 26 Jan 2024 11:55:46 -1000

After creating a new worker, create_worker() is calling kick_pool() to wake
up the new worker task. However, as kick_pool() doesn't do anything if there
is no work pending, it also calls wake_up_process() explicitly. There's no
reason to call kick_pool() at all. wake_up_process() is enough by itself.
Drop the unnecessary kick_pool() call.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
Applied to wq/for-6.9.

 kernel/workqueue.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index ee6aa1b897e0..b6b690a17f7c 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -2217,12 +2217,11 @@ static struct worker *create_worker(struct worker_pool *pool)
 
 	worker->pool->nr_workers++;
 	worker_enter_idle(worker);
-	kick_pool(pool);
 
 	/*
 	 * @worker is waiting on a completion in kthread() and will trigger hung
-	 * check if not woken up soon. As kick_pool() might not have waken it
-	 * up, wake it up explicitly once more.
+	 * check if not woken up soon. As kick_pool() is noop if @pool is empty,
+	 * wake it up explicitly.
 	 */
 	wake_up_process(worker->task);
 
-- 
2.43.0