The quilt patch titled
Subject: mm: compaction: skip more fully scanned pageblock
has been removed from the -mm tree. Its filename was
mm-compaction-skip-more-fully-scanned-pageblock.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Subject: mm: compaction: skip more fully scanned pageblock
Date: Thu, 25 May 2023 20:53:58 +0800
In fast_isolate_around(), it assumes the pageblock is fully scanned if
cc->nr_freepages < cc->nr_migratepages after trying to isolate some free
pages, and will set skip flag to avoid scanning in future. However this
can miss setting the skip flag for a fully scanned pageblock (returned
'start_pfn' is equal to 'end_pfn') in the case where cc->nr_freepages is
larger than cc->nr_migratepages.
So using the returned 'start_pfn' from isolate_freepages_block() and
'end_pfn' to decide if a pageblock is fully scanned makes more sense. It
can also cover the case where cc->nr_freepages < cc->nr_migratepages,
which means the 'start_pfn' is usually equal to 'end_pfn' except some
uncommon fatal error occurs after non-strict mode isolation.
Link: https://lkml.kernel.org/r/f4efd2fa08735794a6d809da3249b6715ba6ad38.1685018752.git.baolin.wang@xxxxxxxxxxxxxxxxx
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/compaction.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/compaction.c~mm-compaction-skip-more-fully-scanned-pageblock
+++ a/mm/compaction.c
@@ -1389,7 +1389,7 @@ fast_isolate_around(struct compact_contr
isolate_freepages_block(cc, &start_pfn, end_pfn, &cc->freepages, 1, false);
/* Skip this pageblock in the future as it's full or nearly full */
- if (cc->nr_freepages < cc->nr_migratepages)
+ if (start_pfn == end_pfn)
set_pageblock_skip(page);
return;
_
Patches currently in -mm which might be from baolin.wang@xxxxxxxxxxxxxxxxx are
