mm, vmscan: only wakeup kswapd once per node for the requested classzone

[linux-2.6-block.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 9b61a55b6e3802ac0308a224c9353ee3cd520852..31edd7776289a12a6c3952a4aae4b1a007d41eac 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3421,6 +3421,7 @@ kswapd_try_sleep:
 void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx)
 {
        pg_data_t *pgdat;
+       int z;
 
        if (!populated_zone(zone))
                return;
@@ -3432,8 +3433,16 @@ void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx)
        pgdat->kswapd_order = max(pgdat->kswapd_order, order);
        if (!waitqueue_active(&pgdat->kswapd_wait))
                return;
-       if (zone_balanced(zone, order, 0))
-               return;
+
+       /* Only wake kswapd if all zones are unbalanced */
+       for (z = 0; z <= classzone_idx; z++) {
+               zone = pgdat->node_zones + z;
+               if (!populated_zone(zone))
+                       continue;
+
+               if (zone_balanced(zone, order, classzone_idx))
+                       return;
+       }
 
        trace_mm_vmscan_wakeup_kswapd(pgdat->node_id, zone_idx(zone), order);
        wake_up_interruptible(&pgdat->kswapd_wait);