memcg: remove nid and zid argument from mem_cgroup_soft_limit_reclaim()

mem_cgroup_soft_limit_reclaim() has zone, nid and zid argument.  but nid
and zid can be calculated from zone.  So remove it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Nishimura Daisuke <d-nishimura@mtf.biglobe.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 8d0bfd7..5e95996 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2865,8 +2865,7 @@
 }
 
 unsigned long mem_cgroup_soft_limit_reclaim(struct zone *zone, int order,
-						gfp_t gfp_mask, int nid,
-						int zid)
+					    gfp_t gfp_mask)
 {
 	unsigned long nr_reclaimed = 0;
 	struct mem_cgroup_per_zone *mz, *next_mz = NULL;
@@ -2878,7 +2877,7 @@
 	if (order > 0)
 		return 0;
 
-	mctz = soft_limit_tree_node_zone(nid, zid);
+	mctz = soft_limit_tree_node_zone(zone_to_nid(zone), zone_idx(zone));
 	/*
 	 * This loop can run a while, specially if mem_cgroup's continuously
 	 * keep exceeding their soft limit and putting the system under
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 06ccda6..c391c32 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2168,7 +2168,6 @@
 		for (i = 0; i <= end_zone; i++) {
 			struct zone *zone = pgdat->node_zones + i;
 			int nr_slab;
-			int nid, zid;
 
 			if (!populated_zone(zone))
 				continue;
@@ -2178,14 +2177,12 @@
 
 			sc.nr_scanned = 0;
 
-			nid = pgdat->node_id;
-			zid = zone_idx(zone);
 			/*
 			 * Call soft limit reclaim before calling shrink_zone.
 			 * For now we ignore the return value
 			 */
-			mem_cgroup_soft_limit_reclaim(zone, order, sc.gfp_mask,
-							nid, zid);
+			mem_cgroup_soft_limit_reclaim(zone, order, sc.gfp_mask);
+
 			/*
 			 * We put equal pressure on every zone, unless one
 			 * zone has way too many pages free already.