The quilt patch titled
Subject: mm: compaction: update pageblock skip when first migration candidate is not at the start
has been removed from the -mm tree. Its filename was
mm-compaction-update-pageblock-skip-when-first-migration-candidate-is-not-at-the-start.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: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Subject: mm: compaction: update pageblock skip when first migration candidate is not at the start
Date: Mon, 15 May 2023 12:33:43 +0100
isolate_migratepages_block should mark a pageblock as skip if scanning
started on an aligned pageblock boundary but it only updates the skip flag
if the first migration candidate is also aligned. Tracing during a
compaction stress load (mmtests: workload-usemem-stress-numa-compact) that
many pageblocks are not marked skip causing excessive scanning of blocks
that had been recently checked. Update pageblock skip based on
"valid_page" which is set if scanning started on a pageblock boundary.
[mgorman@xxxxxxxxxxxxxxxxxxx: fix handling of skip bit]
Link: https://lkml.kernel.org/r/20230602111622.swtxhn6lu2qwgrwq@xxxxxxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20230515113344.6869-4-mgorman@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Tested-by: Raghavendra K T <raghavendra.kt@xxxxxxx>
Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Chuyi Zhou <zhouchuyi@xxxxxxxxxxxxx>
Cc: Jiri Slaby <jirislaby@xxxxxxxxxx>
Cc: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Pedro Falcato <pedro.falcato@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/compaction.c | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
--- a/mm/compaction.c~mm-compaction-update-pageblock-skip-when-first-migration-candidate-is-not-at-the-start
+++ a/mm/compaction.c
@@ -392,18 +392,14 @@ void reset_isolation_suitable(pg_data_t
* Sets the pageblock skip bit if it was clear. Note that this is a hint as
* locks are not required for read/writers. Returns true if it was already set.
*/
-static bool test_and_set_skip(struct compact_control *cc, struct page *page,
- unsigned long pfn)
+static bool test_and_set_skip(struct compact_control *cc, struct page *page)
{
bool skip;
- /* Do no update if skip hint is being ignored */
+ /* Do not update if skip hint is being ignored */
if (cc->ignore_skip_hint)
return false;
- if (!pageblock_aligned(pfn))
- return false;
-
skip = get_pageblock_skip(page);
if (!skip && !cc->no_set_skip_hint)
set_pageblock_skip(page);
@@ -470,8 +466,7 @@ static void update_cached_migrate(struct
{
}
-static bool test_and_set_skip(struct compact_control *cc, struct page *page,
- unsigned long pfn)
+static bool test_and_set_skip(struct compact_control *cc, struct page *page)
{
return false;
}
@@ -1074,11 +1069,17 @@ isolate_migratepages_block(struct compac
lruvec_memcg_debug(lruvec, page_folio(page));
- /* Try get exclusive access under lock */
- if (!skip_updated) {
+ /*
+ * Try get exclusive access under lock. If marked for
+ * skip, the scan is aborted unless the current context
+ * is a rescan to reach the end of the pageblock.
+ */
+ if (!skip_updated && valid_page) {
skip_updated = true;
- if (test_and_set_skip(cc, page, low_pfn))
+ if (test_and_set_skip(cc, valid_page) &&
+ !cc->finish_pageblock) {
goto isolate_abort;
+ }
}
/*
_
Patches currently in -mm which might be from mgorman@xxxxxxxxxxxxxxxxxxx are
