[PATCH] mm: add populated_zone() helper

There are numerous places we check whether a zone is populated or not.

Provide a helper function to check for populated zones and convert all
checks for zone->present_pages.

Signed-off-by: Con Kolivas <kernel@kolivas.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 8d6caa414c4c..c34f4a2c62f8 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -388,6 +388,11 @@ static inline struct zone *next_zone(struct zone *zone)
 #define for_each_zone(zone) \
         for (zone = pgdat_list->node_zones; zone; zone = next_zone(zone))
 
+static inline int populated_zone(struct zone *zone)
+{
+        return (!!zone->present_pages);
+}
+
 static inline int is_highmem_idx(int idx)
 {
         return (idx == ZONE_HIGHMEM);