mempolicy: remove redundant check

Lee's patch "mempolicy: use MPOL_PREFERRED for system-wide default policy"
has made the MPOL_DEFAULT only used in the memory policy APIs.  So, no
need to check in __mpol_equal also.  Also get rid of mpol_match_intent()
and move its logic directly into __mpol_equal().

Signed-off-by: Bob Liu <lliubbo@gmail.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/mempolicy.c

@@ -1787,25 +1787,19 @@ struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol,
 	return tompol;
 }
 
-static int mpol_match_intent(const struct mempolicy *a,
-			     const struct mempolicy *b)
-{
-	if (a->flags != b->flags)
-		return 0;
-	if (!mpol_store_user_nodemask(a))
-		return 1;
-	return nodes_equal(a->w.user_nodemask, b->w.user_nodemask);
-}
-
 /* Slow path of a mempolicy comparison */
 int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
 {
 	if (!a || !b)
 		return 0;
 	if (a->mode != b->mode)
 		return 0;
-	if (a->mode != MPOL_DEFAULT && !mpol_match_intent(a, b))
+	if (a->flags != b->flags)
 		return 0;
+	if (mpol_store_user_nodemask(a))
+		if (!nodes_equal(a->w.user_nodemask, b->w.user_nodemask))
+			return 0;
+
 	switch (a->mode) {
 	case MPOL_BIND:
 		/* Fall through */