From 8e0a891213fbddcec231c9d1d7577c320c77a25a Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Wed, 20 Jan 2016 15:02:26 -0800 Subject: [PATCH] mm: memcontrol: group kmem init and exit functions together Put all the related code to setup and teardown the kmem accounting state into the same location. No functional change intended. Signed-off-by: Johannes Weiner Acked-by: Michal Hocko Cc: Tejun Heo Acked-by: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 157 +++++++++++++++++++++++------------------------- 1 file changed, 76 insertions(+), 81 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 24b6bded13f8..3dd9fe35fe62 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2945,12 +2945,88 @@ static int memcg_propagate_kmem(struct mem_cgroup *memcg) mutex_unlock(&memcg_limit_mutex); return ret; } + +static int memcg_init_kmem(struct mem_cgroup *memcg) +{ + int ret; + + ret = memcg_propagate_kmem(memcg); + if (ret) + return ret; + + return tcp_init_cgroup(memcg); +} + +static void memcg_offline_kmem(struct mem_cgroup *memcg) +{ + struct cgroup_subsys_state *css; + struct mem_cgroup *parent, *child; + int kmemcg_id; + + if (memcg->kmem_state != KMEM_ONLINE) + return; + /* + * Clear the online state before clearing memcg_caches array + * entries. The slab_mutex in memcg_deactivate_kmem_caches() + * guarantees that no cache will be created for this cgroup + * after we are done (see memcg_create_kmem_cache()). + */ + memcg->kmem_state = KMEM_ALLOCATED; + + memcg_deactivate_kmem_caches(memcg); + + kmemcg_id = memcg->kmemcg_id; + BUG_ON(kmemcg_id < 0); + + parent = parent_mem_cgroup(memcg); + if (!parent) + parent = root_mem_cgroup; + + /* + * Change kmemcg_id of this cgroup and all its descendants to the + * parent's id, and then move all entries from this cgroup's list_lrus + * to ones of the parent. After we have finished, all list_lrus + * corresponding to this cgroup are guaranteed to remain empty. The + * ordering is imposed by list_lru_node->lock taken by + * memcg_drain_all_list_lrus(). + */ + css_for_each_descendant_pre(css, &memcg->css) { + child = mem_cgroup_from_css(css); + BUG_ON(child->kmemcg_id != kmemcg_id); + child->kmemcg_id = parent->kmemcg_id; + if (!memcg->use_hierarchy) + break; + } + memcg_drain_all_list_lrus(kmemcg_id, parent->kmemcg_id); + + memcg_free_cache_id(kmemcg_id); +} + +static void memcg_free_kmem(struct mem_cgroup *memcg) +{ + if (memcg->kmem_state == KMEM_ALLOCATED) { + memcg_destroy_kmem_caches(memcg); + static_branch_dec(&memcg_kmem_enabled_key); + WARN_ON(page_counter_read(&memcg->kmem)); + } + tcp_destroy_cgroup(memcg); +} #else static int memcg_update_kmem_limit(struct mem_cgroup *memcg, unsigned long limit) { return -EINVAL; } +static int memcg_init_kmem(struct mem_cgroup *memcg) +{ + return 0; +} +static void memcg_offline_kmem(struct mem_cgroup *memcg) +{ +} +static void memcg_free_kmem(struct mem_cgroup *memcg) +{ +} #endif /* CONFIG_MEMCG_KMEM */ /* @@ -3577,87 +3653,6 @@ static int mem_cgroup_oom_control_write(struct cgroup_subsys_state *css, return 0; } -#ifdef CONFIG_MEMCG_KMEM -static int memcg_init_kmem(struct mem_cgroup *memcg) -{ - int ret; - - ret = memcg_propagate_kmem(memcg); - if (ret) - return ret; - - return tcp_init_cgroup(memcg); -} - -static void memcg_offline_kmem(struct mem_cgroup *memcg) -{ - struct cgroup_subsys_state *css; - struct mem_cgroup *parent, *child; - int kmemcg_id; - - if (memcg->kmem_state != KMEM_ONLINE) - return; - /* - * Clear the online state before clearing memcg_caches array - * entries. The slab_mutex in memcg_deactivate_kmem_caches() - * guarantees that no cache will be created for this cgroup - * after we are done (see memcg_create_kmem_cache()). - */ - memcg->kmem_state = KMEM_ALLOCATED; - - memcg_deactivate_kmem_caches(memcg); - - kmemcg_id = memcg->kmemcg_id; - BUG_ON(kmemcg_id < 0); - - parent = parent_mem_cgroup(memcg); - if (!parent) - parent = root_mem_cgroup; - - /* - * Change kmemcg_id of this cgroup and all its descendants to the - * parent's id, and then move all entries from this cgroup's list_lrus - * to ones of the parent. After we have finished, all list_lrus - * corresponding to this cgroup are guaranteed to remain empty. The - * ordering is imposed by list_lru_node->lock taken by - * memcg_drain_all_list_lrus(). - */ - css_for_each_descendant_pre(css, &memcg->css) { - child = mem_cgroup_from_css(css); - BUG_ON(child->kmemcg_id != kmemcg_id); - child->kmemcg_id = parent->kmemcg_id; - if (!memcg->use_hierarchy) - break; - } - memcg_drain_all_list_lrus(kmemcg_id, parent->kmemcg_id); - - memcg_free_cache_id(kmemcg_id); -} - -static void memcg_free_kmem(struct mem_cgroup *memcg) -{ - if (memcg->kmem_state == KMEM_ALLOCATED) { - memcg_destroy_kmem_caches(memcg); - static_branch_dec(&memcg_kmem_enabled_key); - WARN_ON(page_counter_read(&memcg->kmem)); - } - tcp_destroy_cgroup(memcg); -} -#else -static int memcg_init_kmem(struct mem_cgroup *memcg, struct cgroup_subsys *ss) -{ - return 0; -} - -static void memcg_offline_kmem(struct mem_cgroup *memcg) -{ -} - -static void memcg_free_kmem(struct mem_cgroup *memcg) -{ -} -#endif - #ifdef CONFIG_CGROUP_WRITEBACK struct list_head *mem_cgroup_cgwb_list(struct mem_cgroup *memcg)