Now the kmem states is only used to indicate whether the kmem is offline. Because css_alloc() could fail, then we didn't make the kmem offline. In this case, we need the kmem state to mark this so that memcg_free_kmem() can make the kmem offline. However, we can set ->kmemcg_id to -1 to indicate the kmem has been offline. So we can remove the kmem states to simplify the code. Signed-off-by: Muchun Song <songmuchun@xxxxxxxxxxxxx> --- include/linux/memcontrol.h | 7 ------- mm/memcontrol.c | 9 +++------ 2 files changed, 3 insertions(+), 13 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 0ce97eff79e2..6d0638e13fc1 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -182,12 +182,6 @@ struct mem_cgroup_thresholds { struct mem_cgroup_threshold_ary *spare; }; -enum memcg_kmem_state { - KMEM_NONE, - KMEM_ALLOCATED, - KMEM_ONLINE, -}; - #if defined(CONFIG_SMP) struct memcg_padding { char x[0]; @@ -320,7 +314,6 @@ struct mem_cgroup { #ifdef CONFIG_MEMCG_KMEM int kmemcg_id; - enum memcg_kmem_state kmem_state; struct obj_cgroup __rcu *objcg; struct list_head objcg_list; /* list of inherited objcgs */ #endif diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 9add859f69d7..23a9fc8dc143 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -3630,7 +3630,6 @@ static int memcg_online_kmem(struct mem_cgroup *memcg) return 0; BUG_ON(memcg->kmemcg_id >= 0); - BUG_ON(memcg->kmem_state); memcg_id = memcg_alloc_cache_id(); if (memcg_id < 0) @@ -3647,7 +3646,6 @@ static int memcg_online_kmem(struct mem_cgroup *memcg) static_branch_enable(&memcg_kmem_enabled_key); memcg->kmemcg_id = memcg_id; - memcg->kmem_state = KMEM_ONLINE; return 0; } @@ -3657,11 +3655,9 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) struct mem_cgroup *parent; int kmemcg_id; - if (memcg->kmem_state != KMEM_ONLINE) + if (cgroup_memory_nokmem) return; - memcg->kmem_state = KMEM_ALLOCATED; - parent = parent_mem_cgroup(memcg); if (!parent) parent = root_mem_cgroup; @@ -3675,12 +3671,13 @@ static void memcg_offline_kmem(struct mem_cgroup *memcg) memcg_drain_all_list_lrus(kmemcg_id, parent); memcg_free_cache_id(kmemcg_id); + memcg->kmemcg_id = -1; } static void memcg_free_kmem(struct mem_cgroup *memcg) { /* css_alloc() failed, offlining didn't happen */ - if (unlikely(memcg->kmem_state == KMEM_ONLINE)) + if (unlikely(memcg->kmemcg_id != -1)) memcg_offline_kmem(memcg); } #else -- 2.11.0