diff mbox series

[156/181] mm/compaction.c: micro-optimization remove unnecessary branch

Message ID 20201013235658.mJxIcj5ip%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/181] compiler-clang: add build check for clang 10.0.1 | expand

Commit Message

Andrew Morton Oct. 13, 2020, 11:56 p.m. UTC 
From: Mateusz Nosek <mateusznosek0@gmail.com>
Subject: mm/compaction.c: micro-optimization remove unnecessary branch

The same code can work both for 'zone->compact_considered > defer_limit'
and 'zone->compact_considered >= defer_limit'.  In the latter there is one
branch less which is more effective considering performance.

Link: https://lkml.kernel.org/r/20200913190448.28649-1-mateusznosek0@gmail.com
Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/compaction.c |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)
diff mbox series

Patch

--- a/mm/compaction.c~mm-compactionc-micro-optimization-remove-unnecessary-branch
+++ a/mm/compaction.c
@@ -180,11 +180,10 @@  bool compaction_deferred(struct zone *zo
 		return false;
 
 	/* Avoid possible overflow */
-	if (++zone->compact_considered > defer_limit)
+	if (++zone->compact_considered >= defer_limit) {
 		zone->compact_considered = defer_limit;
-
-	if (zone->compact_considered >= defer_limit)
 		return false;
+	}
 
 	trace_mm_compaction_deferred(zone, order);