[PATCH] mm: Place "not" inside of unlikely() statement in wb_domain_writeout_inc()

From: Steven Rostedt
Date: Mon Feb 06 2017 - 12:01:08 EST


From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>

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.

Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
---
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 290e8b7..94102c7 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
--
2.9.3