mm/memcg: kill mem_cgroup_lru_del()

This patch kills mem_cgroup_lru_del(), we can use
mem_cgroup_lru_del_list() instead.  On 0-order isolation we already have
right lru list id.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/memcontrol.h

@@ -66,7 +66,6 @@ struct lruvec *mem_cgroup_zone_lruvec(struct zone *, struct mem_cgroup *);
 struct lruvec *mem_cgroup_lru_add_list(struct zone *, struct page *,
 				       enum lru_list);
 void mem_cgroup_lru_del_list(struct page *, enum lru_list);
-void mem_cgroup_lru_del(struct page *);
 struct lruvec *mem_cgroup_lru_move_lists(struct zone *, struct page *,
 					 enum lru_list, enum lru_list);
 
@@ -265,10 +264,6 @@ static inline void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru)
 {
 }
 
-static inline void mem_cgroup_lru_del(struct page *page)
-{
-}
-
 static inline struct lruvec *mem_cgroup_lru_move_lists(struct zone *zone,
 						       struct page *page,
 						       enum lru_list from,

mm/memcontrol.c

@@ -1115,11 +1115,6 @@ void mem_cgroup_lru_del_list(struct page *page, enum lru_list lru)
 	mz->lru_size[lru] -= 1 << compound_order(page);
 }
 
-void mem_cgroup_lru_del(struct page *page)
-{
-	mem_cgroup_lru_del_list(page, page_lru(page));
-}
-
 /**
  * mem_cgroup_lru_move_lists - account for moving a page between lrus
  * @zone: zone of the page

mm/vmscan.c

@@ -1057,7 +1057,7 @@ static unsigned long isolate_lru_pages(unsigned long nr_to_scan,
 
 		switch (__isolate_lru_page(page, mode)) {
 		case 0:
-			mem_cgroup_lru_del(page);
+			mem_cgroup_lru_del_list(page, lru);
 			list_move(&page->lru, dst);
 			nr_taken += hpage_nr_pages(page);
 			break;