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 <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 24b6bded13f85603dda0ce95e0a0f5407cf2fc60..3dd9fe35fe62ecfb2dcdfd6a7abb180d8716bca6 100644 (file)
--- 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)