memcg: kill memcg refcnt
Now memcg has the same life cycle as its corresponding cgroup. Kill the
useless refcnt.
Signed-off-by: Li Zefan <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Acked-by: KAMEZAWA Hiroyuki <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Glauber Costa <[email protected]>
Cc: Johannes Weiner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c508258..fa521a2 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -299,8 +299,6 @@
bool oom_lock;
atomic_t under_oom;
- atomic_t refcnt;
-
int swappiness;
/* OOM-Killer disable */
int oom_kill_disable;
@@ -503,8 +501,6 @@
*/
static DEFINE_MUTEX(memcg_create_mutex);
-static void mem_cgroup_put(struct mem_cgroup *memcg);
-
static inline
struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *s)
{
@@ -6238,17 +6234,6 @@
schedule_work(&memcg->work_freeing);
}
-static void __mem_cgroup_put(struct mem_cgroup *memcg, int count)
-{
- if (atomic_sub_and_test(count, &memcg->refcnt))
- call_rcu(&memcg->rcu_freeing, free_rcu);
-}
-
-static void mem_cgroup_put(struct mem_cgroup *memcg)
-{
- __mem_cgroup_put(memcg, 1);
-}
-
/*
* Returns the parent mem_cgroup in memcgroup hierarchy with hierarchy enabled.
*/
@@ -6308,7 +6293,6 @@
memcg->last_scanned_node = MAX_NUMNODES;
INIT_LIST_HEAD(&memcg->oom_notify);
- atomic_set(&memcg->refcnt, 1);
memcg->move_charge_at_immigrate = 0;
mutex_init(&memcg->thresholds_lock);
spin_lock_init(&memcg->move_lock);
@@ -6399,7 +6383,7 @@
struct mem_cgroup *memcg = mem_cgroup_from_cont(cont);
memcg_destroy_kmem(memcg);
- __mem_cgroup_free(memcg);
+ call_rcu(&memcg->rcu_freeing, free_rcu);
}
#ifdef CONFIG_MMU
