From: Peter Enderborg <peter.enderborg@sony.com>
Date: Thu, 4 Jun 2020 10:23:20 +0000 (+0200)
Subject: rcu: Stop shrinker loop
X-Git-Tag: v5.9-rc1~204^2^2^2~5
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c6dfd72b7a3b70a2054db0f73245ea2f762a8452;p=thirdparty%2Fkernel%2Flinux.git

rcu: Stop shrinker loop

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>
---

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index d17e5a08bf43f..c8196fab563c2 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3332,7 +3332,7 @@ 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 = {