Disable zone_reclaim if PF_MALLOC is set.

If the process has already set PF_MALLOC and is already using
current->reclaim_state then do not try to reclaim memory from the zone.
This is set by kswapd and/or synchrononous global reclaim which will not
take it lightly if we zap the reclaim_state.

Signed-off-by: Christoph Lameter <clameter@sig.com>

Index: linux-2.6.16-rc5/mm/vmscan.c
===================================================================
--- linux-2.6.16-rc5.orig/mm/vmscan.c	2006-02-26 21:09:35.000000000 -0800
+++ linux-2.6.16-rc5/mm/vmscan.c	2006-03-08 20:35:47.000000000 -0800
@@ -1883,7 +1883,8 @@ int zone_reclaim(struct zone *zone, gfp_
 
 	if (!(gfp_mask & __GFP_WAIT) ||
 		zone->all_unreclaimable ||
-		atomic_read(&zone->reclaim_in_progress) > 0)
+		atomic_read(&zone->reclaim_in_progress) > 0 ||
+		(p->flags & PF_MEMALLOC))
 			return 0;
 
 	node_id = zone->zone_pgdat->node_id;