From:   Mel Gorman <mgorman@techsingularity.net>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Maxim Levitsky <mlevitsk@redhat.com>,
        Michal Hocko <mhocko@kernel.org>,
        Pedro Falcato <pedro.falcato@gmail.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Chuyi Zhou <zhouchuyi@bytedance.com>,
        Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Mel Gorman <mgorman@techsingularity.net>
Subject: [PATCH 2/4] mm, compaction: Check if a page has been captured before draining PCP pages
Date:   Wed, 25 Jan 2023 13:44:32 +0000
Message-Id: <20230125134434.18017-3-mgorman@techsingularity.net>
In-Reply-To: <20230125134434.18017-1-mgorman@techsingularity.net>
References: <20230125134434.18017-1-mgorman@techsingularity.net>
MIME-Version: 1.0
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If a page has been captured then draining is unnecssary so check first
for a captured page.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
---
 mm/compaction.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/mm/compaction.c b/mm/compaction.c
index c018b0e65720..28711a21a8a2 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -2441,6 +2441,12 @@ compact_zone(struct compact_control *cc, struct capture_control *capc)
 			}
 		}
 
+		/* Stop if a page has been captured */
+		if (capc && capc->page) {
+			ret = COMPACT_SUCCESS;
+			break;
+		}
+
 check_drain:
 		/*
 		 * Has the migration scanner moved away from the previous
@@ -2459,12 +2465,6 @@ compact_zone(struct compact_control *cc, struct capture_control *capc)
 				last_migrated_pfn = 0;
 			}
 		}
-
-		/* Stop if a page has been captured */
-		if (capc && capc->page) {
-			ret = COMPACT_SUCCESS;
-			break;
-		}
 	}
 
 out:
-- 
2.35.3