[PATCH 1/5]memhp: update zone pcp at memory online

[Shaohua Li]

In my test, 128M memory is hot add, but zone's pcp batch is 0, which
is an obvious error. When pages are onlined, zone pcp should be
updated accordingly.

Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx>
---
 include/linux/mm.h  |    2 ++
 mm/memory_hotplug.c |    1 +
 mm/page_alloc.c     |   25 +++++++++++++++++++++++++
 3 files changed, 28 insertions(+)

Index: linux/include/linux/mm.h
===================================================================
--- linux.orig/include/linux/mm.h	2009-06-26 09:41:08.000000000 +0800
+++ linux/include/linux/mm.h	2009-06-26 09:41:10.000000000 +0800
@@ -1073,6 +1073,8 @@ extern void setup_per_cpu_pageset(void);
 static inline void setup_per_cpu_pageset(void) {}
 #endif
 
+extern void zone_pcp_update(struct zone *zone);
+
 /* nommu.c */
 extern atomic_long_t mmap_pages_allocated;
 
Index: linux/mm/memory_hotplug.c
===================================================================
--- linux.orig/mm/memory_hotplug.c	2009-06-26 09:41:08.000000000 +0800
+++ linux/mm/memory_hotplug.c	2009-06-26 09:41:10.000000000 +0800
@@ -422,6 +422,7 @@ int online_pages(unsigned long pfn, unsi
 	zone->present_pages += onlined_pages;
 	zone->zone_pgdat->node_present_pages += onlined_pages;
 
+	zone_pcp_update(zone);
 	setup_per_zone_wmarks();
 	calculate_zone_inactive_ratio(zone);
 	if (onlined_pages) {
Index: linux/mm/page_alloc.c
===================================================================
--- linux.orig/mm/page_alloc.c	2009-06-26 09:41:08.000000000 +0800
+++ linux/mm/page_alloc.c	2009-06-26 09:41:10.000000000 +0800
@@ -3131,6 +3131,31 @@ int zone_wait_table_init(struct zone *zo
 	return 0;
 }
 
+static int __zone_pcp_update(void *data)
+{
+	struct zone *zone = data;
+	int cpu;
+	unsigned long batch = zone_batchsize(zone), flags;
+
+	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		struct per_cpu_pageset *pset;
+		struct per_cpu_pages *pcp;
+
+		pset = zone_pcp(zone, cpu);
+		pcp = &pset->pcp;
+
+		local_irq_save(flags);
+		free_pages_bulk(zone, pcp->count, &pcp->list, 0);
+		setup_pageset(pset, batch);
+		local_irq_restore(flags);
+	}
+}
+
+void zone_pcp_update(struct zone *zone)
+{
+	stop_machine(__zone_pcp_update, zone, NULL);
+}
+
 static __meminit void zone_pcp_init(struct zone *zone)
 {
 	int cpu;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/