[merged mm-stable] mm-vmscan-remove-the-redundant-folioref_reclaim_clean-logic.patch removed from -mm tree

Andrew Morton <[email protected]> Thu, 30 Jul 2026 19:41:45 -0700
Newsgroups org.kernel.vger.mm-commits
Message-ID <[email protected]>
The quilt patch titled
     Subject: mm: vmscan: remove the redundant FOLIOREF_RECLAIM_CLEAN logic
has been removed from the -mm tree.  Its filename was
     mm-vmscan-remove-the-redundant-folioref_reclaim_clean-logic.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 <[email protected]>
Subject: mm: vmscan: remove the redundant FOLIOREF_RECLAIM_CLEAN logic
Date: Mon, 29 Jun 2026 16:04:06 +0800

folio_check_references() will return FOLIOREF_RECLAIM_CLEAN for referenced
file folios, indicating that we can proceed to reclaim clean file folios
or keep them if they are dirty file folios.  However, after commit
6b0dfabb3555 ("fs: Remove aops->writepage"), we no longer attempt to write
back filesystem folios through reclaim.  Instead, we always activate dirty
file folios and wakeup the flush workers to write them back.  As a result,
the FOLIOREF_RECLAIM_CLEAN logic is now redundant: for dirty file folios,
we will no longer reach the 'references == FOLIOREF_RECLAIM_CLEAN' branch
in shrink_folio_list().

Additionally, lazyfree folios are also placed on the file LRU list, but if
a lazyfree folio becomes dirty, try_to_unmap() will fail and thus prevent
reclaim of the re-dirtied lazyfree folios.

Therefore, we can drop the FOLIOREF_RECLAIM_CLEAN-related logic.

Link: https://lore.kernel.org/def70a713e10bcbdf3b9fccc2139ecc07b64f2cb.1782715791.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Reviewed-by: Shakeel Butt <[email protected]>
Cc: Axel Rasmussen <[email protected]>
Cc: Barry Song <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Kairui Song <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Wei Xu <[email protected]>
Cc: Yuanchu Xie <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 mm/vmscan.c |    8 --------
 1 file changed, 8 deletions(-)

--- a/mm/vmscan.c~mm-vmscan-remove-the-redundant-folioref_reclaim_clean-logic
+++ a/mm/vmscan.c
@@ -823,7 +823,6 @@ void folio_putback_lru(struct folio *fol
 
 enum folio_references {
 	FOLIOREF_RECLAIM,
-	FOLIOREF_RECLAIM_CLEAN,
 	FOLIOREF_KEEP,
 	FOLIOREF_ACTIVATE,
 };
@@ -920,10 +919,6 @@ static enum folio_references folio_check
 		return FOLIOREF_KEEP;
 	}
 
-	/* Reclaim if clean, defer dirty folios to writeback */
-	if (referenced_folio && folio_is_file_lru(folio))
-		return FOLIOREF_RECLAIM_CLEAN;
-
 	return FOLIOREF_RECLAIM;
 }
 
@@ -1235,7 +1230,6 @@ retry:
 			stat->nr_ref_keep += nr_pages;
 			goto keep_locked;
 		case FOLIOREF_RECLAIM:
-		case FOLIOREF_RECLAIM_CLEAN:
 			; /* try to reclaim the folio below */
 		}
 
@@ -1381,8 +1375,6 @@ retry:
 				goto activate_locked;
 			}
 
-			if (references == FOLIOREF_RECLAIM_CLEAN)
-				goto keep_locked;
 			if (!may_enter_fs(folio, sc->gfp_mask))
 				goto keep_locked;
 			if (!sc->may_writepage)
_

Patches currently in -mm which might be from [email protected] are

mm-vmscan-convert-folio_referenced-to-use-vma_flags_t.patch
mm-vmscan-add-a-helper-to-identify-file-backed-executable-folios.patch
mm-mglru-promote-mapped-executable-folios-after-first-usage.patch