From f7a449f779608efe1941a0e0c4bd7b5f57000be7 Mon Sep 17 00:00:00 2001 From: Roman Gushchin Date: Mon, 13 Feb 2023 11:29:22 -0800 Subject: mm: memcontrol: rename memcg_kmem_enabled() Currently there are two kmem-related helper functions with a confusing semantics: memcg_kmem_enabled() and mem_cgroup_kmem_disabled(). The problem is that an obvious expectation memcg_kmem_enabled() == !mem_cgroup_kmem_disabled(), can be false. mem_cgroup_kmem_disabled() is similar to mem_cgroup_disabled(): it returns true only if CONFIG_MEMCG_KMEM is not set or the kmem accounting is disabled using a boot time kernel option "cgroup.memory=nokmem". It never changes the value dynamically. memcg_kmem_enabled() is different: it always returns false until the first non-root memory cgroup will get online (assuming the kernel memory accounting is enabled). It's goal is to improve the performance on systems without the cgroupfs mounted/memory controller enabled or on the systems with only the root memory cgroup. To make things more obvious and avoid potential bugs, let's rename memcg_kmem_enabled() to memcg_kmem_online(). Link: https://lkml.kernel.org/r/20230213192922.1146370-1-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin Acked-by: Muchun Song Acked-by: Michal Hocko Cc: Johannes Weiner Cc: Shakeel Butt Cc: Dennis Zhou Signed-off-by: Andrew Morton --- include/linux/memcontrol.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 35478695cabf..5567319027d1 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -1776,24 +1776,24 @@ struct obj_cgroup *get_obj_cgroup_from_page(struct page *page); int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size); void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size); -extern struct static_key_false memcg_kmem_enabled_key; +extern struct static_key_false memcg_kmem_online_key; -static inline bool memcg_kmem_enabled(void) +static inline bool memcg_kmem_online(void) { - return static_branch_likely(&memcg_kmem_enabled_key); + return static_branch_likely(&memcg_kmem_online_key); } static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order) { - if (memcg_kmem_enabled()) + if (memcg_kmem_online()) return __memcg_kmem_charge_page(page, gfp, order); return 0; } static inline void memcg_kmem_uncharge_page(struct page *page, int order) { - if (memcg_kmem_enabled()) + if (memcg_kmem_online()) __memcg_kmem_uncharge_page(page, order); } @@ -1814,7 +1814,7 @@ static inline void count_objcg_event(struct obj_cgroup *objcg, { struct mem_cgroup *memcg; - if (!memcg_kmem_enabled()) + if (!memcg_kmem_online()) return; rcu_read_lock(); @@ -1854,7 +1854,7 @@ static inline struct obj_cgroup *get_obj_cgroup_from_page(struct page *page) return NULL; } -static inline bool memcg_kmem_enabled(void) +static inline bool memcg_kmem_online(void) { return false; } -- cgit v1.2.3