[merged mm-stable] mm-thp-clear-deferred-split-shrinker-bits-when-queues-drain.patch removed from -mm tree

[Andrew Morton <akpm@linux-foundation.org>]

The quilt patch titled
     Subject: mm/thp: clear deferred split shrinker bits when queues drain
has been removed from the -mm tree.  Its filename was
     mm-thp-clear-deferred-split-shrinker-bits-when-queues-drain.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: Lance Yang <lance.yang@linux.dev>
Subject: mm/thp: clear deferred split shrinker bits when queues drain
Date: Tue, 2 Jun 2026 12:34:53 +0800

deferred_split_count() returns the raw list_lru count.  When the
per-memcg, per-node list is empty, that count is 0.

That skips scanning, but it does not tell memcg reclaim that the shrinker
is empty.  shrink_slab_memcg() only clears the memcg shrinker bit when the
count callback reports SHRINK_EMPTY.

Return SHRINK_EMPTY for an empty deferred split list, so the bit can be
cleared once the queue has drained.

Link: https://lore.kernel.org/20260602043453.67597-1-lance.yang@linux.dev
Signed-off-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: David Hildenbrand (Arm) <david@kernel.org>
Acked-by: Usama Arif <usama.arif@linux.dev>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kairui Song <ryncsn@gmail.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nico Pache <npache@redhat.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/huge_memory.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/mm/huge_memory.c~mm-thp-clear-deferred-split-shrinker-bits-when-queues-drain
+++ a/mm/huge_memory.c
@@ -4410,7 +4410,10 @@ void deferred_split_folio(struct folio *
 static unsigned long deferred_split_count(struct shrinker *shrink,
 		struct shrink_control *sc)
 {
-	return list_lru_shrink_count(&deferred_split_lru, sc);
+	unsigned long count;
+
+	count = list_lru_shrink_count(&deferred_split_lru, sc);
+	return count ?: SHRINK_EMPTY;
 }
 
 static bool thp_underused(struct folio *folio)
_

Patches currently in -mm which might be from lance.yang@linux.dev are