mm: mempolicy: turn vma_set_policy() into vma_dup_policy()

Simple cleanup.  Every user of vma_set_policy() does the same work, this
looks a bit annoying imho.  And the new trivial helper which does
mpol_dup() + vma_set_policy() to simplify the callers.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 2 deletions

diff --git a/include/linux/mempolicy.h b/include/linux/mempolicy.h
index 0d7df39a5885..b2f897789838 100644
--- a/include/linux/mempolicy.h
+++ b/include/linux/mempolicy.h
@@ -91,7 +91,6 @@ static inline struct mempolicy *mpol_dup(struct mempolicy *pol)
 }
 
 #define vma_policy(vma) ((vma)->vm_policy)
-#define vma_set_policy(vma, pol) ((vma)->vm_policy = (pol))
 
 static inline void mpol_get(struct mempolicy *pol)
 {
@@ -126,6 +125,7 @@ struct shared_policy {
         spinlock_t lock;
 };
 
+int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst);
 void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol);
 int mpol_set_shared_policy(struct shared_policy *info,
                                 struct vm_area_struct *vma,
@@ -240,7 +240,12 @@ mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx)
 }
 
 #define vma_policy(vma) NULL
-#define vma_set_policy(vma, pol) do {} while(0)
+
+static inline int
+vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst)
+{
+        return 0;
+}
 
 static inline void numa_policy_init(void)
 {