+ mm-thp-replace-folio_memcg-with-folio_memcg_charged.patch added to mm-new branch

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

The patch titled
     Subject: mm: thp: replace folio_memcg() with folio_memcg_charged()
has been added to the -mm mm-new branch.  Its filename is
     mm-thp-replace-folio_memcg-with-folio_memcg_charged.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-thp-replace-folio_memcg-with-folio_memcg_charged.patch

This patch will later appear in the mm-new branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Note, mm-new is a provisional staging ground for work-in-progress
patches, and acceptance into mm-new is a notification for others take
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------------------------------------------------------
From: Muchun Song <songmuchun@bytedance.com>
Subject: mm: thp: replace folio_memcg() with folio_memcg_charged()
Date: Sat, 4 Oct 2025 00:53:15 +0800

Patch series "reparent the THP split queue", v4.

In the future, we will reparent LRU folios during memcg offline to
eliminate dying memory cgroups, which requires reparenting the THP split
queue to its parent memcg.

Similar to list_lru, the split queue is relatively independent and does
not need to be reparented along with objcg and LRU folios (holding objcg
lock and lru lock).  Therefore, we can apply the same mechanism as
list_lru to reparent the split queue first when memcg is offine.


This patch (of 4):

folio_memcg_charged() is intended for use when the user is unconcerned
about the returned memcg pointer.  It is more efficient than
folio_memcg().  Therefore, replace folio_memcg() with
folio_memcg_charged().

Link: https://lkml.kernel.org/r/7bb571c217c3c14c47e86706a50c1b792e88b4d6.1759510072.git.zhengqi.arch@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/huge_memory.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/mm/huge_memory.c~mm-thp-replace-folio_memcg-with-folio_memcg_charged
+++ a/mm/huge_memory.c
@@ -4014,7 +4014,7 @@ bool __folio_unqueue_deferred_split(stru
 	bool unqueued = false;
 
 	WARN_ON_ONCE(folio_ref_count(folio));
-	WARN_ON_ONCE(!mem_cgroup_disabled() && !folio_memcg(folio));
+	WARN_ON_ONCE(!mem_cgroup_disabled() && !folio_memcg_charged(folio));
 
 	ds_queue = get_deferred_split_queue(folio);
 	spin_lock_irqsave(&ds_queue->split_queue_lock, flags);
_

Patches currently in -mm which might be from songmuchun@bytedance.com are

mm-thp-replace-folio_memcg-with-folio_memcg_charged.patch
mm-thp-introduce-folio_split_queue_lock-and-its-variants.patch
mm-thp-use-folio_batch-to-handle-thp-splitting-in-deferred_split_scan.patch