mm: numa: Limit NUMA scanning to migrate-on-fault VMAs

[firefly-linux-kernel-4.4.55.git] / mm / mempolicy.c

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 196d8da2b657f84a662d3caa6dbd85f670e09d60..0e895a2eed5fa47b6a6c7c118c29e3232908e6b9 100644 (file)
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1679,6 +1679,30 @@ struct mempolicy *get_vma_policy(struct task_struct *task,
        return pol;
 }
 
+bool vma_policy_mof(struct task_struct *task, struct vm_area_struct *vma)
+{
+       struct mempolicy *pol = get_task_policy(task);
+       if (vma) {
+               if (vma->vm_ops && vma->vm_ops->get_policy) {
+                       bool ret = false;
+
+                       pol = vma->vm_ops->get_policy(vma, vma->vm_start);
+                       if (pol && (pol->flags & MPOL_F_MOF))
+                               ret = true;
+                       mpol_cond_put(pol);
+
+                       return ret;
+               } else if (vma->vm_policy) {
+                       pol = vma->vm_policy;
+               }
+       }
+
+       if (!pol)
+               return default_policy.flags & MPOL_F_MOF;
+
+       return pol->flags & MPOL_F_MOF;
+}
+
 static int apply_policy_zone(struct mempolicy *policy, enum zone_type zone)
 {
        enum zone_type dynamic_policy_zone = policy_zone;