The patch titled
Subject: mm-compaction-simplify-should_compact_retry-fix
has been added to the -mm mm-unstable branch. Its filename is
mm-compaction-simplify-should_compact_retry-fix.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-compaction-simplify-should_compact_retry-fix.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Johannes Weiner <hannes@xxxxxxxxxxx>
Subject: mm-compaction-simplify-should_compact_retry-fix
Date: Fri, 2 Jun 2023 10:47:05 -0400
Vlastimil points out an unintended change. Previously when hitting
max_retries we'd bump the priority level and restart the loop. Now we
bail out and fail instead. Restore the original behavior.
Link: https://lkml.kernel.org/r/20230602144705.GB161817@xxxxxxxxxxx
Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/page_alloc.c | 24 +++++++++++++-----------
1 file changed, 13 insertions(+), 11 deletions(-)
--- a/mm/page_alloc.c~mm-compaction-simplify-should_compact_retry-fix
+++ a/mm/page_alloc.c
@@ -3506,6 +3506,15 @@ should_compact_retry(struct alloc_contex
return false;
/*
+ * Compaction was skipped due to a lack of free order-0
+ * migration targets. Continue if reclaim can help.
+ */
+ if (compact_result == COMPACT_SKIPPED) {
+ ret = compaction_zonelist_suitable(ac, order, alloc_flags);
+ goto out;
+ }
+
+ /*
* Compaction managed to coalesce some page blocks, but the
* allocation failed presumably due to a race. Retry some.
*/
@@ -3522,17 +3531,10 @@ should_compact_retry(struct alloc_contex
if (order > PAGE_ALLOC_COSTLY_ORDER)
max_retries /= 4;
- ret = ++(*compaction_retries) <= max_retries;
- goto out;
- }
-
- /*
- * Compaction was skipped due to a lack of free order-0
- * migration targets. Continue if reclaim can help.
- */
- if (compact_result == COMPACT_SKIPPED) {
- ret = compaction_zonelist_suitable(ac, order, alloc_flags);
- goto out;
+ if (++(*compaction_retries) <= max_retries) {
+ ret = true;
+ goto out;
+ }
}
/*
_
Patches currently in -mm which might be from hannes@xxxxxxxxxxx are
mm-compaction-remove-compaction-result-helpers.patch
mm-compaction-simplify-should_compact_retry.patch
mm-compaction-simplify-should_compact_retry-fix.patch
mm-compaction-refactor-__compaction_suitable.patch
mm-compaction-refactor-__compaction_suitable-fix.patch
mm-compaction-remove-unnecessary-is_via_compact_memory-checks.patch
mm-compaction-drop-redundant-watermark-check-in-compaction_zonelist_suitable.patch
mm-compaction-have-compaction_suitable-return-bool.patch
mm-page_isolation-write-proper-kerneldoc.patch
mm-compaction-avoid-gfp_nofs-abba-deadlock.patch
