vmscan: fix it to take care of nodemask

try_to_free_pages() is used for the direct reclaim of up to
SWAP_CLUSTER_MAX pages when watermarks are low.  The caller to
alloc_pages_nodemask() can specify a nodemask of nodes that are allowed to
be used but this is not passed to try_to_free_pages().  This can lead to
unnecessary reclaim of pages that are unusable by the caller and int the
worst case lead to allocation failure as progress was not been make where
it is needed.

This patch passes the nodemask used for alloc_pages_nodemask() to
try_to_free_pages().

Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

4 files changed, 15 insertions, 5 deletions

diff --git a/fs/buffer.c b/fs/buffer.c
index 0c14f8d52ee5..c77b848c3d43 100644
--- a/fs/buffer.c
+++ b/fs/buffer.c
@@ -290,7 +290,7 @@ static void free_more_memory(void)
 						&zone);
 		if (zone)
 			try_to_free_pages(node_zonelist(nid, GFP_NOFS), 0,
-						GFP_NOFS);
+						GFP_NOFS, NULL);
 	}
 }
 
diff --git a/include/linux/swap.h b/include/linux/swap.h
index d30215578877..b8b0c4ce83e6 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -212,7 +212,7 @@ static inline void lru_cache_add_active_file(struct page *page)
 
 /* linux/mm/vmscan.c */
 extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
-					gfp_t gfp_mask);
+					gfp_t gfp_mask, nodemask_t *mask);
 extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem,
 						  gfp_t gfp_mask, bool noswap,
 						  unsigned int swappiness);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index cbd532161f68..0284e528748d 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1582,7 +1582,8 @@ nofail_alloc:
 	reclaim_state.reclaimed_slab = 0;
 	p->reclaim_state = &reclaim_state;
 
-	did_some_progress = try_to_free_pages(zonelist, order, gfp_mask);
+	did_some_progress = try_to_free_pages(zonelist, order,
+						gfp_mask, nodemask);
 
 	p->reclaim_state = NULL;
 	lockdep_clear_current_reclaim_state();
diff --git a/mm/vmscan.c b/mm/vmscan.c
index f4619c6cd59e..06e72693b458 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -78,6 +78,12 @@ struct scan_control {
 	/* Which cgroup do we reclaim from */
 	struct mem_cgroup *mem_cgroup;
 
+	/*
+	 * Nodemask of nodes allowed by the caller. If NULL, all nodes
+	 * are scanned.
+	 */
+	nodemask_t	*nodemask;
+
 	/* Pluggable isolate pages callback */
 	unsigned long (*isolate_pages)(unsigned long nr, struct list_head *dst,
 			unsigned long *scanned, int order, int mode,
@@ -1538,7 +1544,8 @@ static void shrink_zones(int priority, struct zonelist *zonelist,
 	struct zone *zone;
 
 	sc->all_unreclaimable = 1;
-	for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
+	for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx,
+					sc->nodemask) {
 		if (!populated_zone(zone))
 			continue;
 		/*
@@ -1683,7 +1690,7 @@ out:
 }
 
 unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
-								gfp_t gfp_mask)
+				gfp_t gfp_mask, nodemask_t *nodemask)
 {
 	struct scan_control sc = {
 		.gfp_mask = gfp_mask,
@@ -1694,6 +1701,7 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
 		.order = order,
 		.mem_cgroup = NULL,
 		.isolate_pages = isolate_pages_global,
+		.nodemask = nodemask,
 	};
 
 	return do_try_to_free_pages(zonelist, &sc);
@@ -1714,6 +1722,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
 		.order = 0,
 		.mem_cgroup = mem_cont,
 		.isolate_pages = mem_cgroup_isolate_pages,
+		.nodemask = NULL, /* we don't care the placement */
 	};
 	struct zonelist *zonelist;