[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, 4 insertions, 4 deletions

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 5c8a412b43f4..7681d8ee04fe 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -897,7 +897,7 @@ shrink_caches(struct zone **zones, struct scan_control *sc)
         for (i = 0; zones[i] != NULL; i++) {
                 struct zone *zone = zones[i];
 
-                if (zone->present_pages == 0)
+                if (!populated_zone(zone))
                         continue;
 
                 if (!cpuset_zone_allowed(zone, __GFP_HARDWALL))
@@ -1069,7 +1069,7 @@ loop_again:
                         for (i = pgdat->nr_zones - 1; i >= 0; i--) {
                                 struct zone *zone = pgdat->node_zones + i;
 
-                                if (zone->present_pages == 0)
+                                if (!populated_zone(zone))
                                         continue;
 
                                 if (zone->all_unreclaimable &&
@@ -1106,7 +1106,7 @@ scan:
                         struct zone *zone = pgdat->node_zones + i;
                         int nr_slab;
 
-                        if (zone->present_pages == 0)
+                        if (!populated_zone(zone))
                                 continue;
 
                         if (zone->all_unreclaimable && priority != DEF_PRIORITY)
@@ -1258,7 +1258,7 @@ void wakeup_kswapd(struct zone *zone, int order)
 {
         pg_data_t *pgdat;
 
-        if (zone->present_pages == 0)
+        if (!populated_zone(zone))
                 return;
 
         pgdat = zone->zone_pgdat;