+ memcg-dont-call-propagate_protected_usage-for-v1.patch added to mm-unstable branch

+ memcg-dont-call-propagate_protected_usage-for-v1.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: memcg: don't call propagate_protected_usage() for v1
has been added to the -mm mm-unstable branch.  Its filename is
     memcg-dont-call-propagate_protected_usage-for-v1.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/memcg-dont-call-propagate_protected_usage-for-v1.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: don't call propagate_protected_usage() for v1
Date: Thu, 27 Feb 2025 23:58:06 -0800

Patch series "page_counter cleanup and size reduction".

Commit c6f53ed8f213a ("mm, memcg: cg2 memory{.swap,}.peak write handlers")
accidently increased the size of struct page_counter.  This series
rearrange the fields to reduce its size and also has some cleanups.


This patch (of 3):

Memcg-v1 does not support memory protection (min/low) and thus there is no
need to track protected memory usage for it.

Link: https://lkml.kernel.org/r/20250228075808.207484-1-shakeel.butt@linux.dev
Link: https://lkml.kernel.org/r/20250228075808.207484-2-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 |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/mm/memcontrol.c~memcg-dont-call-propagate_protected_usage-for-v1
+++ a/mm/memcontrol.c
@@ -3601,6 +3601,7 @@ mem_cgroup_css_alloc(struct cgroup_subsy
 {
 	struct mem_cgroup *parent = mem_cgroup_from_css(parent_css);
 	struct mem_cgroup *memcg, *old_memcg;
+	bool memcg_on_dfl = cgroup_subsys_on_dfl(memory_cgrp_subsys);
 
 	old_memcg = set_active_memcg(parent);
 	memcg = mem_cgroup_alloc(parent);
@@ -3618,7 +3619,7 @@ mem_cgroup_css_alloc(struct cgroup_subsy
 	if (parent) {
 		WRITE_ONCE(memcg->swappiness, mem_cgroup_swappiness(parent));
 
-		page_counter_init(&memcg->memory, &parent->memory, true);
+		page_counter_init(&memcg->memory, &parent->memory, memcg_on_dfl);
 		page_counter_init(&memcg->swap, &parent->swap, false);
 #ifdef CONFIG_MEMCG_V1
 		WRITE_ONCE(memcg->oom_kill_disable, READ_ONCE(parent->oom_kill_disable));
@@ -3638,7 +3639,7 @@ mem_cgroup_css_alloc(struct cgroup_subsy
 		return &memcg->css;
 	}
 
-	if (cgroup_subsys_on_dfl(memory_cgrp_subsys) && !cgroup_memory_nosocket)
+	if (memcg_on_dfl && !cgroup_memory_nosocket)
 		static_branch_inc(&memcg_sockets_enabled_key);
 
 	if (!cgroup_memory_nobpf)
_

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