mm: remember what the preferred zone is for zone_statistics

18ea7e71 · Mel Gorman <[email protected]> · 2008-04-28 02:12:14 -07:00

On NUMA, zone_statistics() is used to record events like numa hit, miss and
foreign.  It assumes that the first zone in a zonelist is the preferred zone.
When multiple zonelists are replaced by one that is filtered, this is no
longer the case.

This patch records what the preferred zone is rather than assuming the first
zone in the zonelist is it.  This simplifies the reading of later patches in
this set.

Signed-off-by: Mel Gorman <[email protected]>
Signed-off-by: Lee Schermerhorn <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Mel Gorman <[email protected]>
Reviewed-by: Christoph Lameter <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Nick Piggin <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

Commit: 18ea7e710d2452fa726814a406779188028cf1bf
Parents: 0e88460d

Changes

3 files changed · +9 −8

File	Status	Add	Del	Content
include/linux/vmstat.h	modified	+1	−1	View file
mm/page_alloc.c	modified	+5	−4	View file
mm/vmstat.c	modified	+3	−3	View file

include/linux/vmstat.h

View file

diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index 9f1b4b4..e726b6d 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -174,7 +174,7 @@ static inline unsigned long node_page_state(int node,
 		zone_page_state(&zones[ZONE_MOVABLE], item);
 }
 
-extern void zone_statistics(struct zonelist *, struct zone *);
+extern void zone_statistics(struct zone *, struct zone *);
 
 #else
 

mm/page_alloc.c

View file

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 63ff718..187efd4 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1050,7 +1050,7 @@ void split_page(struct page *page, unsigned int order)
  * we cheat by calling it from here, in the order > 0 path.  Saves a branch
  * or two.
  */
-static struct page *buffered_rmqueue(struct zonelist *zonelist,
+static struct page *buffered_rmqueue(struct zone *preferred_zone,
 			struct zone *zone, int order, gfp_t gfp_flags)
 {
 	unsigned long flags;
@@ -1102,7 +1102,7 @@ again:
 	}
 
 	__count_zone_vm_events(PGALLOC, zone, 1 << order);
-	zone_statistics(zonelist, zone);
+	zone_statistics(preferred_zone, zone);
 	local_irq_restore(flags);
 	put_cpu();
 
@@ -1383,7 +1383,7 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order,
 	struct zone **z;
 	struct page *page = NULL;
 	int classzone_idx = zone_idx(zonelist->zones[0]);
-	struct zone *zone;
+	struct zone *zone, *preferred_zone;
 	nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
 	int zlc_active = 0;		/* set if using zonelist_cache */
 	int did_zlc_setup = 0;		/* just call zlc_setup() one time */
@@ -1395,6 +1395,7 @@ zonelist_scan:
 	 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
 	 */
 	z = zonelist->zones;
+	preferred_zone = *z;
 
 	do {
 		/*
@@ -1433,7 +1434,7 @@ zonelist_scan:
 			}
 		}
 
-		page = buffered_rmqueue(zonelist, zone, order, gfp_mask);
+		page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask);
 		if (page)
 			break;
 this_zone_full:

mm/vmstat.c

View file

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 7c7286e..879bcc0 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -364,13 +364,13 @@ void refresh_cpu_vm_stats(int cpu)
  *
  * Must be called with interrupts disabled.
  */
-void zone_statistics(struct zonelist *zonelist, struct zone *z)
+void zone_statistics(struct zone *preferred_zone, struct zone *z)
 {
-	if (z->zone_pgdat == zonelist->zones[0]->zone_pgdat) {
+	if (z->zone_pgdat == preferred_zone->zone_pgdat) {
 		__inc_zone_state(z, NUMA_HIT);
 	} else {
 		__inc_zone_state(z, NUMA_MISS);
-		__inc_zone_state(zonelist->zones[0], NUMA_FOREIGN);
+		__inc_zone_state(preferred_zone, NUMA_FOREIGN);
 	}
 	if (z->node == numa_node_id())
 		__inc_zone_state(z, NUMA_LOCAL);