From: Andrey Ryabinin <aryabinin@virtuozzo.com>
Date: Tue, 10 Apr 2018 23:27:55 +0000 (-0700)
Subject: mm/vmscan: remove redundant current_may_throttle() check
X-Git-Tag: v4.17-rc1~52^2~134
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=c4fd4fa58018bab781c17c8d92d70106a37b6a5c;p=users%2Fhch%2Fmisc.git

mm/vmscan: remove redundant current_may_throttle() check

Only kswapd can have non-zero nr_immediate, and current_may_throttle()
is always true for kswapd (PF_LESS_THROTTLE bit is never set) thus it's
enough to check stat.nr_immediate only.

Link: http://lkml.kernel.org/r/20180315164553.17856-4-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 6d74b12099bd..403f59edd53e 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1807,7 +1807,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
 		 * that pages are cycling through the LRU faster than
 		 * they are written so also forcibly stall.
 		 */
-		if (stat.nr_immediate && current_may_throttle())
+		if (stat.nr_immediate)
 			congestion_wait(BLK_RW_ASYNC, HZ/10);
 	}