From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/migration: avoid unneeded nodemask_t initialization

Avoid unneeded next_pass and this_pass initialization as they're always
set before using to save possible cpu cycles when there are plenty of
nodes in the system.

Link: https://lkml.kernel.org/r/20220318111709.60311-8-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/migrate.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/mm/migrate.c~mm-migration-avoid-unneeded-nodemask_t-initialization
+++ a/mm/migrate.c
@@ -2357,8 +2357,8 @@ out_clear:
  */
 static void __set_migration_target_nodes(void)
 {
-	nodemask_t next_pass	= NODE_MASK_NONE;
-	nodemask_t this_pass	= NODE_MASK_NONE;
+	nodemask_t next_pass;
+	nodemask_t this_pass;
 	nodemask_t used_targets = NODE_MASK_NONE;
 	int node, best_distance;
 
_