The patch titled
Subject: mm/vmscan: do not demote PG_dropbehind folios
has been added to the -mm mm-unstable branch. Its filename is
mm-vmscan-do-not-demote-pg_dropbehind-folios.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-vmscan-do-not-demote-pg_dropbehind-folios.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: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Subject: mm/vmscan: do not demote PG_dropbehind folios
Date: Thu, 30 Jan 2025 12:00:48 +0200
PG_dropbehind flag indicates that the folio need to be freed immediately.
No point in demoting it.
Link: https://lkml.kernel.org/r/20250130100050.1868208-11-kirill.shutemov@xxxxxxxxxxxxxxx
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>
Cc: Chengming Zhou <chengming.zhou@xxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Cc: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: Dave Airlie <airlied@xxxxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: gehao <gehao@xxxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
Cc: Jason A. Donenfeld <jason@xxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Jonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Josef Bacik <josef@xxxxxxxxxxxxxx>
Cc: "Masami Hiramatsu (Google)" <mhiramat@xxxxxxxxxx>
Cc: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
Cc: Mattew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Miklos Szeredi <miklos@xxxxxxxxxx>
Cc: Nhat Pham <nphamcs@xxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Ran Xiaokai <ran.xiaokai@xxxxxxxxxx>
Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Cc: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Cc: Tvrtko Ursulin <tursulin@xxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/vmscan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/vmscan.c~mm-vmscan-do-not-demote-pg_dropbehind-folios
+++ a/mm/vmscan.c
@@ -1231,7 +1231,7 @@ retry:
* Before reclaiming the folio, try to relocate
* its contents to another node.
*/
- if (do_demote_pass &&
+ if (do_demote_pass && !folio_test_dropbehind(folio) &&
(thp_migration_supported() || !folio_test_large(folio))) {
list_add(&folio->lru, &demote_folios);
folio_unlock(folio);
_
Patches currently in -mm which might be from kirill.shutemov@xxxxxxxxxxxxxxx are
mm-migrate-transfer-pg_dropbehind-to-the-new-folio.patch
drm-i915-gem-convert-__shmem_writeback-to-folios.patch
drm-i915-gem-use-pg_dropbehind-instead-of-pg_reclaim.patch
mm-zswap-use-pg_dropbehind-instead-of-pg_reclaim.patch
mm-truncate-use-folio_set_dropbehind-instead-of-deactivate_file_folio.patch
mm-vmscan-use-pg_dropbehind-instead-of-pg_reclaim.patch
mm-vmscan-use-pg_dropbehind-instead-of-pg_reclaim-in-shrink_folio_list.patch
mm-mglru-check-pg_dropbehind-instead-of-pg_reclaim-in-lru_gen_folio_seq.patch
mm-remove-pg_reclaim.patch
mm-vmscan-do-not-demote-pg_dropbehind-folios.patch
mm-rename-pg_dropbehind-to-pg_reclaim.patch
