From: Baolin Wang <baolin.wang@linux.alibaba.com>
Date: Tue, 10 Jan 2023 13:36:22 +0000 (+0800)
Subject: mm: compaction: avoid fragmentation score calculation for empty zones
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9e5522715e6941bcfdc08d066a79d6da0f8cec8e;p=linux.git

mm: compaction: avoid fragmentation score calculation for empty zones

There is no need to calculate the fragmentation score for empty zones.

Link: https://lkml.kernel.org/r/100331ad9d274a9725e687b00d85d75d7e4a17c7.1673342761.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/mm/compaction.c b/mm/compaction.c
index 0fd6c81a78099..b758b00a48854 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -2025,6 +2025,8 @@ static unsigned int fragmentation_score_node(pg_data_t *pgdat)
 		struct zone *zone;
 
 		zone = &pgdat->node_zones[zoneid];
+		if (!populated_zone(zone))
+			continue;
 		score += fragmentation_score_zone_weighted(zone);
 	}