+ memcg-bypass-root-memcg-check-for-skmem-charging.patch added to mm-unstable branch

+ memcg-bypass-root-memcg-check-for-skmem-charging.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: memcg: bypass root memcg check for skmem charging
has been added to the -mm mm-unstable branch.  Its filename is
     memcg-bypass-root-memcg-check-for-skmem-charging.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/memcg-bypass-root-memcg-check-for-skmem-charging.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: Shakeel Butt <shakeel.butt@linux.dev>
Subject: memcg: bypass root memcg check for skmem charging
Date: Thu, 27 Feb 2025 18:23:54 -0800

The root memcg is never associated with a socket in mem_cgroup_sk_alloc,
so there is no need to check if the given memcg is root for the skmem
charging code path.

Link: https://lkml.kernel.org/r/20250228022354.2624249-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin (Cruise) <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

--- a/mm/memcontrol.c~memcg-bypass-root-memcg-check-for-skmem-charging
+++ a/mm/memcontrol.c
@@ -4888,7 +4888,7 @@ bool mem_cgroup_charge_skmem(struct mem_
 	if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
 		return memcg1_charge_skmem(memcg, nr_pages, gfp_mask);
 
-	if (try_charge(memcg, gfp_mask, nr_pages) == 0) {
+	if (try_charge_memcg(memcg, gfp_mask, nr_pages) == 0) {
 		mod_memcg_state(memcg, MEMCG_SOCK, nr_pages);
 		return true;
 	}
_

Patches currently in -mm which might be from shakeel.butt@linux.dev are

memcg-add-hierarchical-effective-limits-for-v2.patch
memcg-dont-call-propagate_protected_usage-for-v1.patch
page_counter-track-failcnt-only-for-legacy-cgroups.patch
page_counter-reduce-struct-page_counter-size.patch
memcg-bypass-root-memcg-check-for-skmem-charging.patch