mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies

As they all do the same thing: sanity check and save nodemask info, create
one mpol_new_nodemask() to reduce redundancy.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Feng Tang <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Ben Widawsky <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Huang Ying <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Mike Kravetz <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Author: ftang1

mm/mempolicy.c

@@ -192,7 +192,7 @@ static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig,
 	nodes_onto(*ret, tmp, *rel);
 }
 
-static int mpol_new_interleave(struct mempolicy *pol, const nodemask_t *nodes)
+static int mpol_new_nodemask(struct mempolicy *pol, const nodemask_t *nodes)
 {
 	if (nodes_empty(*nodes))
 		return -EINVAL;
@@ -210,22 +210,6 @@ static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes)
 	return 0;
 }
 
-static int mpol_new_preferred_many(struct mempolicy *pol, const nodemask_t *nodes)
-{
-	if (nodes_empty(*nodes))
-		return -EINVAL;
-	pol->nodes = *nodes;
-	return 0;
-}
-
-static int mpol_new_bind(struct mempolicy *pol, const nodemask_t *nodes)
-{
-	if (nodes_empty(*nodes))
-		return -EINVAL;
-	pol->nodes = *nodes;
-	return 0;
-}
-
 /*
  * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if
  * any, for the new policy.  mpol_new() has already validated the nodes
@@ -405,22 +389,22 @@ static const struct mempolicy_operations mpol_ops[MPOL_MAX] = {
 		.rebind = mpol_rebind_default,
 	},
 	[MPOL_INTERLEAVE] = {
-		.create = mpol_new_interleave,
+		.create = mpol_new_nodemask,
 		.rebind = mpol_rebind_nodemask,
 	},
 	[MPOL_PREFERRED] = {
 		.create = mpol_new_preferred,
 		.rebind = mpol_rebind_preferred,
 	},
 	[MPOL_BIND] = {
-		.create = mpol_new_bind,
+		.create = mpol_new_nodemask,
 		.rebind = mpol_rebind_nodemask,
 	},
 	[MPOL_LOCAL] = {
 		.rebind = mpol_rebind_default,
 	},
 	[MPOL_PREFERRED_MANY] = {
-		.create = mpol_new_preferred_many,
+		.create = mpol_new_nodemask,
 		.rebind = mpol_rebind_preferred,
 	},
 };