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        Peter Enderborg <peter.enderborg@sony.com>,
        "Paul E . McKenney" <paulmck@kernel.org>
Subject: [PATCH tip/core/rcu 19/26] rcu: Stop shrinker loop
Date:   Mon, 22 Jun 2020 17:21:40 -0700
Message-Id: <20200623002147.25750-19-paulmck@kernel.org>
In-Reply-To: <20200623002128.GA25456@paulmck-ThinkPad-P72>
References: <20200623002128.GA25456@paulmck-ThinkPad-P72>
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From: Peter Enderborg <peter.enderborg@sony.com>

The count and scan can be separated in time, and there is a fair chance
that all work is already done when the scan starts, which might in turn
result in a needless retry.  This commit therefore avoids this retry by
returning SHRINK_STOP.

Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
 kernel/rcu/tree.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 67912ad..0806762 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3314,7 +3314,7 @@ kfree_rcu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
 			break;
 	}
 
-	return freed;
+	return freed == 0 ? SHRINK_STOP : freed;
 }
 
 static struct shrinker kfree_rcu_shrinker = {
-- 
2.9.5