From 01b9da291c4969354807b52956f4aae1f41b4924 Mon Sep 17 00:00:00 2001
From: Qi Zheng <zhengqi.arch@bytedance.com>
Date: Thu, 5 Mar 2026 19:52:49 +0800
Subject: mm: memcontrol: convert objcg to be per-memcg per-node type
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Convert objcg to be per-memcg per-node type, so that when reparent LRU
folios later, we can hold the lru lock at the node level, thus avoiding
holding too many lru locks at once.

[zhengqi.arch@bytedance.com: reset pn->orig_objcg to NULL]
  Link: https://lore.kernel.org/20260309112939.31937-1-qi.zheng@linux.dev
[akpm@linux-foundation.org: fix comment typo, per Usama.  Reflow comment to 80 cols]
[devnexen@gmail.com: fix obj_cgroup leak in mem_cgroup_css_online() error path]
  Link: https://lore.kernel.org/20260322193631.45457-1-devnexen@gmail.com
[devnexen@gmail.com: add newline, per Qi Zheng]
  Link: https://lore.kernel.org/20260323063007.7783-1-devnexen@gmail.com
Link: https://lore.kernel.org/56c04b1c5d54f75ccdc12896df6c1ca35403ecc3.1772711148.git.zhengqi.arch@bytedance.com
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Signed-off-by: David Carlier <devnexen@gmail.com>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Allen Pais <apais@linux.microsoft.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chen Ridong <chenridong@huawei.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Hamza Mahfooz <hamzamahfooz@linux.microsoft.com>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Imran Khan <imran.f.khan@oracle.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamalesh Babulal <kamalesh.babulal@oracle.com>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Usama Arif <usamaarif642@gmail.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Wei Xu <weixugc@google.com>
Cc: Yosry Ahmed <yosry@kernel.org>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Usama Arif <usama.arif@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/sched.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'include/linux/sched.h')

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 5a5d3dbc9cdf..0d27775546f8 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1533,7 +1533,7 @@ struct task_struct {
 	/* Used by memcontrol for targeted memcg charge: */
 	struct mem_cgroup		*active_memcg;
 
-	/* Cache for current->cgroups->memcg->objcg lookups: */
+	/* Cache for current->cgroups->memcg->nodeinfo[nid]->objcg lookups: */
 	struct obj_cgroup		*objcg;
 #endif
 
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