From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx195.postini.com [74.125.245.195]) by kanga.kvack.org (Postfix) with SMTP id 271396B0044 for ; Thu, 20 Sep 2012 02:40:47 -0400 (EDT) From: Minchan Kim Subject: [PATCH v3] memory-hotplug: fix zone stat mismatch Date: Thu, 20 Sep 2012 15:43:25 +0900 Message-Id: <1348123405-30641-1-git-send-email-minchan@kernel.org> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Minchan Kim , Kamezawa Hiroyuki , Yasuaki Ishimatsu , KOSAKI Motohiro During memory-hotplug, I found NR_ISOLATED_[ANON|FILE] are increasing so that kernel are hang out. The cause is that when we do memory-hotadd after memory-remove, __zone_pcp_update clear out zone's ZONE_STAT_ITEMS in setup_pageset although vm_stat_diff of all CPU still have value. In addtion, when we offline all pages of the zone, we reset them in zone_pcp_reset without drain so that we lost zone stat item. This patch fixes it. * from v2 * Add Reviewed-by - Wen * from v1 * drain offline patch - KOSAKI, Wen Cc: Kamezawa Hiroyuki Cc: Yasuaki Ishimatsu Cc: KOSAKI Motohiro Reviewed-by: Wen Congyang Signed-off-by: Minchan Kim --- include/linux/vmstat.h | 4 ++++ mm/page_alloc.c | 7 +++++++ mm/vmstat.c | 12 ++++++++++++ 3 files changed, 23 insertions(+) diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h index ad2cfd5..5d31876 100644 --- a/include/linux/vmstat.h +++ b/include/linux/vmstat.h @@ -198,6 +198,8 @@ extern void __dec_zone_state(struct zone *, enum zone_stat_item); void refresh_cpu_vm_stats(int); void refresh_zone_stat_thresholds(void); +void drain_zonestat(struct zone *zone, struct per_cpu_pageset *); + int calculate_pressure_threshold(struct zone *zone); int calculate_normal_threshold(struct zone *zone); void set_pgdat_percpu_threshold(pg_data_t *pgdat, @@ -251,6 +253,8 @@ static inline void __dec_zone_page_state(struct page *page, static inline void refresh_cpu_vm_stats(int cpu) { } static inline void refresh_zone_stat_thresholds(void) { } +static inline void drain_zonestat(struct zone *zone, + struct per_cpu_pageset *pset) { } #endif /* CONFIG_SMP */ extern const char * const vmstat_text[]; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ab58346..980f2e7 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5904,6 +5904,7 @@ static int __meminit __zone_pcp_update(void *data) local_irq_save(flags); if (pcp->count > 0) free_pcppages_bulk(zone, pcp->count, pcp); + drain_zonestat(zone, pset); setup_pageset(pset, batch); local_irq_restore(flags); } @@ -5920,10 +5921,16 @@ void __meminit zone_pcp_update(struct zone *zone) void zone_pcp_reset(struct zone *zone) { unsigned long flags; + int cpu; + struct per_cpu_pageset *pset; /* avoid races with drain_pages() */ local_irq_save(flags); if (zone->pageset != &boot_pageset) { + for_each_online_cpu(cpu) { + pset = per_cpu_ptr(zone->pageset, cpu); + drain_zonestat(zone, pset); + } free_percpu(zone->pageset); zone->pageset = &boot_pageset; } diff --git a/mm/vmstat.c b/mm/vmstat.c index b3e3b9d..d4cc1c2 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -495,6 +495,18 @@ void refresh_cpu_vm_stats(int cpu) atomic_long_add(global_diff[i], &vm_stat[i]); } +void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset) +{ + int i; + + for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) + if (pset->vm_stat_diff[i]) { + int v = pset->vm_stat_diff[i]; + pset->vm_stat_diff[i] = 0; + atomic_long_add(v, &zone->vm_stat[i]); + atomic_long_add(v, &vm_stat[i]); + } +} #endif #ifdef CONFIG_NUMA -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org