memcg: remove mem_cgroup_cal_reclaim()

Now, get_scan_ratio() return correct value although memcg reclaim.  Then,
mem_cgroup_calc_reclaim() can be removed.

So, memcg reclaim get the same capability of anon/file reclaim balancing
as global reclaim now.

Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 10 insertions, 48 deletions

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 36b8ebb39b82..8752052da8df 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -97,9 +97,6 @@ extern void mem_cgroup_note_reclaim_priority(struct mem_cgroup *mem,
                                                         int priority);
 extern void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem,
                                                         int priority);
-
-extern long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone,
-                                        int priority, enum lru_list lru);
 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg,
                                     struct zone *zone);
 unsigned long mem_cgroup_zone_nr_pages(struct mem_cgroup *memcg,
@@ -244,13 +241,6 @@ static inline void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem,
 {
 }
 
-static inline long mem_cgroup_calc_reclaim(struct mem_cgroup *mem,
-                                        struct zone *zone, int priority,
-                                        enum lru_list lru)
-{
-        return 0;
-}
-
 static inline bool mem_cgroup_disabled(void)
 {
         return true;
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 7b7f4dc05035..b8c1e5acc25a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -414,27 +414,6 @@ void mem_cgroup_record_reclaim_priority(struct mem_cgroup *mem, int priority)
         mem->prev_priority = priority;
 }
 
-/*
- * Calculate # of pages to be scanned in this priority/zone.
- * See also vmscan.c
- *
- * priority starts from "DEF_PRIORITY" and decremented in each loop.
- * (see include/linux/mmzone.h)
- */
-
-long mem_cgroup_calc_reclaim(struct mem_cgroup *mem, struct zone *zone,
-                                        int priority, enum lru_list lru)
-{
-        long nr_pages;
-        int nid = zone->zone_pgdat->node_id;
-        int zid = zone_idx(zone);
-        struct mem_cgroup_per_zone *mz = mem_cgroup_zoneinfo(mem, nid, zid);
-
-        nr_pages = MEM_CGROUP_ZSTAT(mz, lru);
-
-        return (nr_pages >> priority);
-}
-
 int mem_cgroup_inactive_anon_is_low(struct mem_cgroup *memcg, struct zone *zone)
 {
         unsigned long active;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 56fc7abe4d23..66bb6ef44b5f 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1466,30 +1466,23 @@ static void shrink_zone(int priority, struct zone *zone,
         get_scan_ratio(zone, sc, percent);
 
         for_each_evictable_lru(l) {
-                if (scan_global_lru(sc)) {
-                        int file = is_file_lru(l);
-                        int scan;
+                int file = is_file_lru(l);
+                int scan;
 
-                        scan = zone_page_state(zone, NR_LRU_BASE + l);
-                        if (priority) {
-                                scan >>= priority;
-                                scan = (scan * percent[file]) / 100;
-                        }
+                scan = zone_page_state(zone, NR_LRU_BASE + l);
+                if (priority) {
+                        scan >>= priority;
+                        scan = (scan * percent[file]) / 100;
+                }
+                if (scan_global_lru(sc)) {
                         zone->lru[l].nr_scan += scan;
                         nr[l] = zone->lru[l].nr_scan;
                         if (nr[l] >= swap_cluster_max)
                                 zone->lru[l].nr_scan = 0;
                         else
                                 nr[l] = 0;
-                } else {
-                        /*
-                         * This reclaim occurs not because zone memory shortage
-                         * but because memory controller hits its limit.
-                         * Don't modify zone reclaim related data.
-                         */
-                        nr[l] = mem_cgroup_calc_reclaim(sc->mem_cgroup, zone,
-                                                                priority, l);
-                }
+                } else
+                        nr[l] = scan;
         }
 
         while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] ||