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From:   "Joel Fernandes (Google)" <joel@joelfernandes.org>
To:     rcu@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, rushikesh.s.kadam@intel.com,
        urezki@gmail.com, neeraj.iitr10@gmail.com, frederic@kernel.org,
        paulmck@kernel.org, rostedt@goodmis.org, youssefesmat@google.com,
        surenb@google.com, Joel Fernandes <joel@joelfernandes.org>
Subject: [PATCH v8 11/13] workqueue: Make queue_rcu_work() use call_rcu_flush()
Date:   Tue, 11 Oct 2022 18:01:40 +0000
Message-Id: <20221011180142.2742289-12-joel@joelfernandes.org>
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From: Uladzislau Rezki <urezki@gmail.com>

call_rcu() changes to save power will slow down RCU workqueue items
queued via queue_rcu_work(). This may not be an issue, however we cannot
assume that workqueue users are OK with long delays. Use
call_rcu_flush() API instead which reverts to the old behavior.

Signed-off-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
---
 kernel/workqueue.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index aeea9731ef80..fe1146d97f1a 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -1771,7 +1771,7 @@ bool queue_rcu_work(struct workqueue_struct *wq, struct rcu_work *rwork)
 
 	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
 		rwork->wq = wq;
-		call_rcu(&rwork->rcu, rcu_work_rcufn);
+		call_rcu_flush(&rwork->rcu, rcu_work_rcufn);
 		return true;
 	}
 
-- 
2.38.0.rc1.362.ged0d419d3c-goog