+ memcg-move-do_memsw_account-to-config_memcg_v1.patch added to mm-unstable branch

+ memcg-move-do_memsw_account-to-config_memcg_v1.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: memcg: move do_memsw_account() to CONFIG_MEMCG_V1
has been added to the -mm mm-unstable branch.  Its filename is
     memcg-move-do_memsw_account-to-config_memcg_v1.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/memcg-move-do_memsw_account-to-config_memcg_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: move do_memsw_account() to CONFIG_MEMCG_V1
Date: Wed, 12 Mar 2025 15:25:52 -0700

The do_memsw_account() is used to enable or disable legacy memory+swap
accounting in memory cgroup.  However with disabled CONFIG_MEMCG_V1, we
don't need to keep checking it.  So, let's always return false for
!CONFIG_MEMCG_V1 configs.

Before the patch:

$ size mm/memcontrol.o
   text    data     bss     dec     hex filename
  49928   10736    4172   64836    fd44 mm/memcontrol.o

After the patch:

$ size mm/memcontrol.o
   text    data     bss     dec     hex filename
  49430   10480    4172   64082    fa52 mm/memcontrol.o

Link: https://lkml.kernel.org/r/20250312222552.3284173-1-shakeel.butt@linux.dev
Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol-v1.h |   13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

--- a/mm/memcontrol-v1.h~memcg-move-do_memsw_account-to-config_memcg_v1
+++ a/mm/memcontrol-v1.h
@@ -22,12 +22,6 @@
 	     iter != NULL;				\
 	     iter = mem_cgroup_iter(NULL, iter, NULL))
 
-/* Whether legacy memory+swap accounting is active */
-static inline bool do_memsw_account(void)
-{
-	return !cgroup_subsys_on_dfl(memory_cgrp_subsys);
-}
-
 unsigned long mem_cgroup_usage(struct mem_cgroup *memcg, bool swap);
 
 void drain_all_stock(struct mem_cgroup *root_memcg);
@@ -42,6 +36,12 @@ struct mem_cgroup *mem_cgroup_id_get_onl
 /* Cgroup v1-specific declarations */
 #ifdef CONFIG_MEMCG_V1
 
+/* Whether legacy memory+swap accounting is active */
+static inline bool do_memsw_account(void)
+{
+	return !cgroup_subsys_on_dfl(memory_cgrp_subsys);
+}
+
 unsigned long memcg_events_local(struct mem_cgroup *memcg, int event);
 unsigned long memcg_page_state_local(struct mem_cgroup *memcg, int idx);
 unsigned long memcg_page_state_local_output(struct mem_cgroup *memcg, int item);
@@ -94,6 +94,7 @@ extern struct cftype mem_cgroup_legacy_f
 
 #else	/* CONFIG_MEMCG_V1 */
 
+static inline bool do_memsw_account(void) { return false; }
 static inline bool memcg1_alloc_events(struct mem_cgroup *memcg) { return true; }
 static inline void memcg1_free_events(struct mem_cgroup *memcg) {}
 
_

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

memcg-drain-obj-stock-on-cpu-hotplug-teardown.patch
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
memcg-avoid-refill_stock-for-root-memcg.patch
memcg-move-do_memsw_account-to-config_memcg_v1.patch