From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753293Ab2ITHVg (ORCPT ); Thu, 20 Sep 2012 03:21:36 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:56552 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751439Ab2ITHVf (ORCPT ); Thu, 20 Sep 2012 03:21:35 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.7.4 Message-ID: <505AC3E9.4030009@jp.fujitsu.com> Date: Thu, 20 Sep 2012 16:21:13 +0900 From: Yasuaki Ishimatsu User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:15.0) Gecko/20120907 Thunderbird/15.0.1 MIME-Version: 1.0 To: Minchan Kim CC: Andrew Morton , , , Kamezawa Hiroyuki , KOSAKI Motohiro Subject: Re: [PATCH v3] memory-hotplug: fix zone stat mismatch References: <1348123405-30641-1-git-send-email-minchan@kernel.org> In-Reply-To: <1348123405-30641-1-git-send-email-minchan@kernel.org> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Minchan, Sorry for late reply. 2012/09/20 15:43, Minchan Kim wrote: > During memory-hotplug, I found NR_ISOLATED_[ANON|FILE] > are increasing so that kernel are hang out. Why does your system hang out by increasing NR_ISOLATED_[ANON|FILE]? I cannot understand what has happened by your system. Thanks, Yasuaki Ishimatsu > > 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 >