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authorLai Jiangshan <laijs@cn.fujitsu.com>2013-02-23 04:33:22 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-02-24 05:50:13 +0400
commitd3eb1570a9221b1b3ea8f6f460a9674c1bb761f1 (patch)
tree35792d7c35ba7012ea8d43bf5243e04a6b90323f /mm
parent8a356ce38e134b3b09b439e88dc770f8f5567648 (diff)
downloadlinux-d3eb1570a9221b1b3ea8f6f460a9674c1bb761f1.tar.xz
mempolicy: fix is_valid_nodemask()
is_valid_nodemask() was introduced by commit 19770b32609b ("mm: filter based on a nodemask as well as a gfp_mask"). but it does not match its comments, because it does not check the zone which > policy_zone. Also in commit b377fd3982ad ("Apply memory policies to top two highest zones when highest zone is ZONE_MOVABLE"), this commits told us, if highest zone is ZONE_MOVABLE, we should also apply memory policies to it. so ZONE_MOVABLE should be valid zone for policies. is_valid_nodemask() need to be changed to match it. Fix: check all zones, even its zoneid > policy_zone. Use nodes_intersects() instead open code to check it. Reported-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/mempolicy.c36
1 files changed, 22 insertions, 14 deletions
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index e2df1c1fb41f..6f7979c566d9 100644
--- a/mm/mempolicy.c
+++ b/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;