+ mm-list_lru-disable-memcg_aware-when-cgroupmemory-is-set-to-nokmem.patch added to mm-unstable branch

+ mm-list_lru-disable-memcg_aware-when-cgroupmemory-is-set-to-nokmem.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: list_lru: disable memcg_aware when cgroup.memory is set to "nokmem"
has been added to the -mm mm-unstable branch.  Its filename is
     mm-list_lru-disable-memcg_aware-when-cgroupmemory-is-set-to-nokmem.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-list_lru-disable-memcg_aware-when-cgroupmemory-is-set-to-nokmem.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: Haifeng Xu <haifeng.xu@shopee.com>
Subject: mm: list_lru: disable memcg_aware when cgroup.memory is set to "nokmem"
Date: Thu, 28 Dec 2023 06:27:14 +0000

Actually, when using a boot time kernel option "cgroup.memory=nokmem", all
lru items are inserted to list_lru_node.  But for those users who invoke
list_lru_init_memcg() to initialize list_lru, list_lru_memcg_aware()
returns true.  And this brings unneeded operations related to memcg.

To make things more convenient, let's disable memcg_aware when
cgroup.memory is set to "nokmem".

Link: https://lkml.kernel.org/r/20231228062715.338672-1-haifeng.xu@shopee.com
Signed-off-by: Haifeng Xu <haifeng.xu@shopee.com>
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/list_lru.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/mm/list_lru.c~mm-list_lru-disable-memcg_aware-when-cgroupmemory-is-set-to-nokmem
+++ a/mm/list_lru.c
@@ -567,6 +567,9 @@ int __list_lru_init(struct list_lru *lru
 		lru->shrinker_id = shrinker->id;
 	else
 		lru->shrinker_id = -1;
+
+	if (mem_cgroup_kmem_disabled())
+		memcg_aware = false;
 #endif
 
 	lru->node = kcalloc(nr_node_ids, sizeof(*lru->node), GFP_KERNEL);
_

Patches currently in -mm which might be from haifeng.xu@shopee.com are

mm-list_lru-disable-memcg_aware-when-cgroupmemory-is-set-to-nokmem.patch
mm-list_lru-remove-unused-macro-list_lru_init_key.patch