From afe9ae3fda96d1ccfd28f7b0c1f68527a570ccd4 Mon Sep 17 00:00:00 2001 From: Guopeng Zhang Date: Mon, 13 Jul 2026 17:03:04 +0800 Subject: [PATCH] mm: memcontrol: factor out memcg kmem uncharge sequence The kmem-uncharge sequence (mod_memcg_state(MEMCG_KMEM) + memcg1_account_kmem + conditional memcg_uncharge) is duplicated verbatim in obj_cgroup_release() and drain_obj_stock_slot(). Factor it into a small memcg_uncharge_kmem() helper. The reference get/put stays at the call sites, as they differ. No functional change. Link: https://lore.kernel.org/20260713090304.3015329-1-guopeng.zhang@linux.dev Signed-off-by: Guopeng Zhang Acked-by: Tao Cui Acked-by: Johannes Weiner Reviewed-by: Muchun Song Acked-by: Shakeel Butt Cc: Michal Hocko Cc: Roman Gushchin Signed-off-by: Andrew Morton --- mm/memcontrol.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5dc103a98e74..8319ad8c5c23 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -137,6 +137,14 @@ bool mem_cgroup_kmem_disabled(void) static void memcg_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages); +static void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned int nr_pages) +{ + mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); + memcg1_account_kmem(memcg, -nr_pages); + if (!mem_cgroup_is_root(memcg)) + memcg_uncharge(memcg, nr_pages); +} + static void obj_cgroup_release(struct percpu_ref *ref) { struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt); @@ -172,10 +180,7 @@ static void obj_cgroup_release(struct percpu_ref *ref) struct mem_cgroup *memcg; memcg = get_mem_cgroup_from_objcg(objcg); - mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); - memcg1_account_kmem(memcg, -nr_pages); - if (!mem_cgroup_is_root(memcg)) - memcg_uncharge(memcg, nr_pages); + memcg_uncharge_kmem(memcg, nr_pages); mem_cgroup_put(memcg); } @@ -3329,10 +3334,7 @@ static void drain_obj_stock_slot(struct obj_stock_pcp *stock, int i) memcg = get_mem_cgroup_from_objcg(old); - mod_memcg_state(memcg, MEMCG_KMEM, -nr_pages); - memcg1_account_kmem(memcg, -nr_pages); - if (!mem_cgroup_is_root(memcg)) - memcg_uncharge(memcg, nr_pages); + memcg_uncharge_kmem(memcg, nr_pages); css_put(&memcg->css); }