[PATCH] mm/page_alloc: Split per cpu page lists and zone stats -fix -fix

[Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>]

mm/ is not W=1 clean for make allnoconfig but this patch accidentally
made it worse for i386 with the warning

  mm/vmstat.c: In function â??refresh_cpu_vm_statsâ??:
  mm/vmstat.c:785:34: warning: unused variable â??pcpâ?? [-Wunused-variable]
     struct per_cpu_pages __percpu *pcp = zone->per_cpu_pageset;
                                    ^~~

This is a second fix to the mmotm patch
mm-page_alloc-split-per-cpu-page-lists-and-zone-stats.patch.

Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
---
 mm/vmstat.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/mm/vmstat.c b/mm/vmstat.c
index a2c3f58253be..f1400ba46beb 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -782,7 +782,9 @@ static int refresh_cpu_vm_stats(bool do_pagesets)
 
 	for_each_populated_zone(zone) {
 		struct per_cpu_zonestat __percpu *pzstats = zone->per_cpu_zonestats;
+#ifdef CONFIG_NUMA
 		struct per_cpu_pages __percpu *pcp = zone->per_cpu_pageset;
+#endif
 
 		for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
 			int v;