From 48b7d2dd49533c3263bbd5dba5f6dca478a2048b Mon Sep 17 00:00:00 2001
From: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Date: Fri, 24 Feb 2017 14:59:24 -0800
Subject: [PATCH] mm/page-writeback.c: place "not" inside of unlikely()
statement in wb_domain_writeout_inc()
The likely/unlikely profiler noticed that the unlikely statement in
wb_domain_writeout_inc() is constantly wrong. This is due to the "not"
(!) being outside the unlikely statement. It is likely that
dom->period_time will be set, but unlikely that it wont be. Move the
not into the unlikely statement.
Link: http://lkml.kernel.org/r/20170206120035.3c2e2b91@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
mm/page-writeback.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 2164498258594..ae6e601f0a58e 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -580,7 +580,7 @@ static void wb_domain_writeout_inc(struct wb_domain *dom,
__fprop_inc_percpu_max(&dom->completions, completions,
max_prop_frac);
/* First event after period switching was turned off? */
- if (!unlikely(dom->period_time)) {
+ if (unlikely(!dom->period_time)) {
/*
* We can race with other __bdi_writeout_inc calls here but
* it does not cause any harm since the resulting time when
--
2.39.5