mm: page_alloc: determine migratetype only once

The check for ALLOC_CMA in __alloc_pages_nodemask() derives migratetype
from gfp_mask in each retry pass, although the migratetype variable
already has the value determined and it does not change.  Use the variable
and perform the check only once.  Also convert #ifdef CONFIG_CMA to
IS_ENABLED.

Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 4 deletions

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index f3bc59f2ed52..e63bf7744a0c 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2776,6 +2776,9 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
         if (unlikely(!zonelist->_zonerefs->zone))
                 return NULL;
 
+        if (IS_ENABLED(CONFIG_CMA) && migratetype == MIGRATE_MOVABLE)
+                alloc_flags |= ALLOC_CMA;
+
 retry_cpuset:
         cpuset_mems_cookie = read_mems_allowed_begin();
 
@@ -2787,10 +2790,6 @@ retry_cpuset:
                 goto out;
         classzone_idx = zonelist_zone_idx(preferred_zoneref);
 
-#ifdef CONFIG_CMA
-        if (allocflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE)
-                alloc_flags |= ALLOC_CMA;
-#endif
         /* First allocation attempt */
         page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
                         zonelist, high_zoneidx, alloc_flags,