From c3e046dec8115bac9a8d44163f20871ebb49807a Mon Sep 17 00:00:00 2001
From: Lai Jiangshan <laijs@cn.fujitsu.com>
Date: Fri, 22 Feb 2013 16:33:22 -0800
Subject: [PATCH] --- yaml --- r: 356527 b: refs/heads/master c:
 d3eb1570a9221b1b3ea8f6f460a9674c1bb761f1 h: refs/heads/master i:   356525:
 585d9335d05714eca29a8a35520a9ba5bb01d921   356523:
 8f220b3c1a99aad5ce1bb17662d94ee7a09a1f9d   356519:
 257083ac58a46fda8f8f80e26ce9040edd2c2694   356511:
 85254c7cd879d4e13aadc64b85ee199e052d4748 v: v3

---
 [refs]               |  2 +-
 trunk/mm/mempolicy.c | 36 ++++++++++++++++++++++--------------
 2 files changed, 23 insertions(+), 15 deletions(-)

diff --git a/[refs] b/[refs]
index 4c5ee9c93052..7d25d7a410e4 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 8a356ce38e134b3b09b439e88dc770f8f5567648
+refs/heads/master: d3eb1570a9221b1b3ea8f6f460a9674c1bb761f1
diff --git a/trunk/mm/mempolicy.c b/trunk/mm/mempolicy.c
index e2df1c1fb41f..6f7979c566d9 100644
--- a/trunk/mm/mempolicy.c
+++ b/trunk/mm/mempolicy.c
@@ -161,19 +161,7 @@ static const struct mempolicy_operations {
 /* Check that the nodemask contains at least one populated zone */
 static int is_valid_nodemask(const nodemask_t *nodemask)
 {
-	int nd, k;
-
-	for_each_node_mask(nd, *nodemask) {
-		struct zone *z;
-
-		for (k = 0; k <= policy_zone; k++) {
-			z = &NODE_DATA(nd)->node_zones[k];
-			if (z->present_pages > 0)
-				return 1;
-		}
-	}
-
-	return 0;
+	return nodes_intersects(*nodemask, node_states[N_MEMORY]);
 }
 
 static inline int mpol_store_user_nodemask(const struct mempolicy *pol)
@@ -1644,6 +1632,26 @@ struct mempolicy *get_vma_policy(struct task_struct *task,
 	return pol;
 }
 
+static int apply_policy_zone(struct mempolicy *policy, enum zone_type zone)
+{
+	enum zone_type dynamic_policy_zone = policy_zone;
+
+	BUG_ON(dynamic_policy_zone == ZONE_MOVABLE);
+
+	/*
+	 * if policy->v.nodes has movable memory only,
+	 * we apply policy when gfp_zone(gfp) = ZONE_MOVABLE only.
+	 *
+	 * policy->v.nodes is intersect with node_states[N_MEMORY].
+	 * so if the following test faile, it implies
+	 * policy->v.nodes has movable memory only.
+	 */
+	if (!nodes_intersects(policy->v.nodes, node_states[N_HIGH_MEMORY]))
+		dynamic_policy_zone = ZONE_MOVABLE;
+
+	return zone >= dynamic_policy_zone;
+}
+
 /*
  * Return a nodemask representing a mempolicy for filtering nodes for
  * page allocation
@@ -1652,7 +1660,7 @@ static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *policy)
 {
 	/* Lower zones don't get a nodemask applied for MPOL_BIND */
 	if (unlikely(policy->mode == MPOL_BIND) &&
-			gfp_zone(gfp) >= policy_zone &&
+			apply_policy_zone(policy, gfp_zone(gfp)) &&
 			cpuset_nodemask_valid_mems_allowed(&policy->v.nodes))
 		return &policy->v.nodes;