[PATCH v2 -mm 1/2] memcg: remove unused mem_cgroup->oom_wakeups

[Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

Since 4942642080ea ("mm: memcg: handle non-error OOM situations more
gracefully"), nobody uses mem_cgroup->oom_wakeups.  Remove it.

While at it, also fold memcg_wakeup_oom() into memcg_oom_recover()
which is its only user.  This cleanup was suggested by Michal.

Signed-off-by: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: Michal Hocko <mhocko-AlSwsSmVLrQ@public.gmane.org>
---
Patch updated.  I dropped the comment as it's kinda obvious from the
context and the use of __wake_up().

Thanks.

 mm/memcontrol.c |   10 +---------
 1 file changed, 1 insertion(+), 9 deletions(-)

--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -287,7 +287,6 @@ struct mem_cgroup {
 
 	bool		oom_lock;
 	atomic_t	under_oom;
-	atomic_t	oom_wakeups;
 
 	int	swappiness;
 	/* OOM-Killer disable */
@@ -1850,17 +1849,10 @@ static int memcg_oom_wake_function(wait_
 	return autoremove_wake_function(wait, mode, sync, arg);
 }
 
-static void memcg_wakeup_oom(struct mem_cgroup *memcg)
-{
-	atomic_inc(&memcg->oom_wakeups);
-	/* for filtering, pass "memcg" as argument. */
-	__wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg);
-}
-
 static void memcg_oom_recover(struct mem_cgroup *memcg)
 {
 	if (memcg && atomic_read(&memcg->under_oom))
-		memcg_wakeup_oom(memcg);
+		__wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, memcg);
 }
 
 static void mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order)