Add N_CPU node state

We need the check for a node with cpu in zone reclaim. Zone reclaim will not
allow remote zone reclaim if a node has a cpu.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Tested-by:  Lee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: Bob Picco <bob.picco@hp.com>
---
 include/linux/nodemask.h |    1 +
 mm/page_alloc.c          |    4 +++-
 mm/vmscan.c              |    4 +---
 3 files changed, 5 insertions(+), 4 deletions(-)

Index: linux-2.6.23-rc1-mm2/include/linux/nodemask.h
===================================================================
--- linux-2.6.23-rc1-mm2.orig/include/linux/nodemask.h	2007-08-03 16:34:58.000000000 -0700
+++ linux-2.6.23-rc1-mm2/include/linux/nodemask.h	2007-08-03 16:35:26.000000000 -0700
@@ -349,6 +349,7 @@ enum node_states {
 #else
 	N_HIGH_MEMORY = N_NORMAL_MEMORY,
 #endif
+	N_CPU,		/* The node has one or more cpus */
 	NR_NODE_STATES
 };
 
Index: linux-2.6.23-rc1-mm2/mm/page_alloc.c
===================================================================
--- linux-2.6.23-rc1-mm2.orig/mm/page_alloc.c	2007-08-03 16:34:58.000000000 -0700
+++ linux-2.6.23-rc1-mm2/mm/page_alloc.c	2007-08-03 16:35:26.000000000 -0700
@@ -2742,6 +2742,7 @@ static struct per_cpu_pageset boot_pages
 static int __cpuinit process_zones(int cpu)
 {
 	struct zone *zone, *dzone;
+	int node = cpu_to_node(cpu);
 
 	for_each_zone(zone) {
 
@@ -2749,7 +2750,7 @@ static int __cpuinit process_zones(int c
 			continue;
 
 		zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset),
-					 GFP_KERNEL, cpu_to_node(cpu));
+					 GFP_KERNEL, node);
 		if (!zone_pcp(zone, cpu))
 			goto bad;
 
@@ -2760,6 +2761,7 @@ static int __cpuinit process_zones(int c
 			 	(zone->present_pages / percpu_pagelist_fraction));
 	}
 
+	node_set_state(node, N_CPU);
 	return 0;
 bad:
 	for_each_zone(dzone) {
Index: linux-2.6.23-rc1-mm2/mm/vmscan.c
===================================================================
--- linux-2.6.23-rc1-mm2.orig/mm/vmscan.c	2007-08-03 16:35:08.000000000 -0700
+++ linux-2.6.23-rc1-mm2/mm/vmscan.c	2007-08-03 16:35:26.000000000 -0700
@@ -1836,7 +1836,6 @@ static int __zone_reclaim(struct zone *z
 
 int zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 {
-	cpumask_t mask;
 	int node_id;
 
 	/*
@@ -1873,8 +1872,7 @@ int zone_reclaim(struct zone *zone, gfp_
 	 * as wide as possible.
 	 */
 	node_id = zone_to_nid(zone);
-	mask = node_to_cpumask(node_id);
-	if (!cpus_empty(mask) && node_id != numa_node_id())
+	if (node_state(node_id, N_CPU) && node_id != numa_node_id())
 		return 0;
 	return __zone_reclaim(zone, gfp_mask, order);
 }