3 files changed, 30 insertions, 15 deletions

diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index 05fddd5bee5d..74357cb9bc7c 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -68,6 +68,7 @@ struct mempolicy {
                 nodemask_t       nodes;         /* interleave */
                 /* undefined for default */
         } v;
+        nodemask_t cpuset_mems_allowed; /* mempolicy relative to these nodes */
 };
 
 /*
@@ -146,7 +147,9 @@ struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp,
 
 extern void numa_default_policy(void);
 extern void numa_policy_init(void);
-extern void numa_policy_rebind(const nodemask_t *old, const nodemask_t *new);
+extern void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *new);
+extern void mpol_rebind_task(struct task_struct *tsk,
+                                        const nodemask_t *new);
 extern struct mempolicy default_policy;
 extern struct zonelist *huge_zonelist(struct vm_area_struct *vma,
                 unsigned long addr);
@@ -221,7 +224,12 @@ static inline void numa_default_policy(void)
 {
 }
 
-static inline void numa_policy_rebind(const nodemask_t *old,
+static inline void mpol_rebind_policy(struct mempolicy *pol,
+                                        const nodemask_t *new)
+{
+}
+
+static inline void mpol_rebind_task(struct task_struct *tsk,
                                         const nodemask_t *new)
 {
 }
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 0d0dbbd6560a..8f764de3a9e7 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -643,7 +643,7 @@ void cpuset_update_task_memory_state()
                 tsk->cpuset_mems_generation = cs->mems_generation;
                 task_unlock(tsk);
                 up(&callback_sem);
-                numa_policy_rebind(&oldmem, &tsk->mems_allowed);
+                mpol_rebind_task(tsk, &tsk->mems_allowed);
                 if (!nodes_equal(oldmem, tsk->mems_allowed)) {
                         if (migrate) {
                                 do_migrate_pages(tsk->mm, &oldmem,
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 34d566ac147f..c39bd86f4ea0 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -180,6 +180,7 @@ static struct mempolicy *mpol_new(int mode, nodemask_t *nodes)
                 break;
         }
         policy->policy = mode;
+        policy->cpuset_mems_allowed = cpuset_mems_allowed(current);
         return policy;
 }
 
@@ -1411,25 +1412,31 @@ void numa_default_policy(void)
 }
 
 /* Migrate a policy to a different set of nodes */
-static void rebind_policy(struct mempolicy *pol, const nodemask_t *old,
-                                                        const nodemask_t *new)
+void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask)
 {
+        nodemask_t *mpolmask;
         nodemask_t tmp;
 
         if (!pol)
                 return;
+        mpolmask = &pol->cpuset_mems_allowed;
+        if (nodes_equal(*mpolmask, *newmask))
+                return;
 
         switch (pol->policy) {
         case MPOL_DEFAULT:
                 break;
         case MPOL_INTERLEAVE:
-                nodes_remap(tmp, pol->v.nodes, *old, *new);
+                nodes_remap(tmp, pol->v.nodes, *mpolmask, *newmask);
                 pol->v.nodes = tmp;
-                current->il_next = node_remap(current->il_next, *old, *new);
+                *mpolmask = *newmask;
+                current->il_next = node_remap(current->il_next,
+                                                *mpolmask, *newmask);
                 break;
         case MPOL_PREFERRED:
                 pol->v.preferred_node = node_remap(pol->v.preferred_node,
-                                                                *old, *new);
+                                                *mpolmask, *newmask);
+                *mpolmask = *newmask;
                 break;
         case MPOL_BIND: {
                 nodemask_t nodes;
@@ -1439,7 +1446,7 @@ static void rebind_policy(struct mempolicy *pol, const nodemask_t *old,
                 nodes_clear(nodes);
                 for (z = pol->v.zonelist->zones; *z; z++)
                         node_set((*z)->zone_pgdat->node_id, nodes);
-                nodes_remap(tmp, nodes, *old, *new);
+                nodes_remap(tmp, nodes, *mpolmask, *newmask);
                 nodes = tmp;
 
                 zonelist = bind_zonelist(&nodes);
@@ -1454,6 +1461,7 @@ static void rebind_policy(struct mempolicy *pol, const nodemask_t *old,
                         kfree(pol->v.zonelist);
                         pol->v.zonelist = zonelist;
                 }
+                *mpolmask = *newmask;
                 break;
         }
         default:
@@ -1463,14 +1471,13 @@ static void rebind_policy(struct mempolicy *pol, const nodemask_t *old,
 }
 
 /*
- * Someone moved this task to different nodes.  Fixup mempolicies.
- *
- * TODO - fixup current->mm->vma and shmfs/tmpfs/hugetlbfs policies as well,
- * once we have a cpuset mechanism to mark which cpuset subtree is migrating.
+ * Wrapper for mpol_rebind_policy() that just requires task
+ * pointer, and updates task mempolicy.
  */
-void numa_policy_rebind(const nodemask_t *old, const nodemask_t *new)
+
+void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
 {
-        rebind_policy(current->mempolicy, old, new);
+        mpol_rebind_policy(tsk->mempolicy, new);
 }
 
 /*