mm/page_alloc.c: fix wrong initialization when sysctl_min_unmapped_ra…

…tio changes

Before resetting min_unmapped_pages, we need to initialize
min_unmapped_pages rather than min_slab_pages.

Fixes: a5f5f91 (mm: convert zone_reclaim to node_reclaim)
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Joonsoo Kim <[email protected]>
Acked-by: Mel Gorman <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Cc: Johannes Weiner <[email protected]>
Cc: Minchan Kim <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

mm/page_alloc.c

@@ -6854,7 +6854,7 @@ int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write,
 		return rc;
 
 	for_each_online_pgdat(pgdat)
-		pgdat->min_slab_pages = 0;
+		pgdat->min_unmapped_pages = 0;
 
 	for_each_zone(zone)
 		zone->zone_pgdat->min_unmapped_pages += (zone->managed_pages *