From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f173.google.com (mail-pd0-f173.google.com [209.85.192.173]) by kanga.kvack.org (Postfix) with ESMTP id BE2D56B00EC for ; Wed, 12 Nov 2014 03:38:07 -0500 (EST) Received: by mail-pd0-f173.google.com with SMTP id v10so11848438pde.32 for ; Wed, 12 Nov 2014 00:38:07 -0800 (PST) Received: from heian.cn.fujitsu.com ([59.151.112.132]) by mx.google.com with ESMTP id 1si22318631pdr.58.2014.11.12.00.38.05 for ; Wed, 12 Nov 2014 00:38:06 -0800 (PST) From: Tang Chen Subject: [PATCH v3 2/2] mem-hotplug: Reset node present pages when hot-adding a new pgdat. Date: Wed, 12 Nov 2014 16:37:14 +0800 Message-ID: <1415781434-20230-3-git-send-email-tangchen@cn.fujitsu.com> In-Reply-To: <1415781434-20230-1-git-send-email-tangchen@cn.fujitsu.com> References: <1415781434-20230-1-git-send-email-tangchen@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, grygorii.strashko@ti.com, yinghai@kernel.org, isimatu.yasuaki@jp.fujitsu.com, fabf@skynet.be, nzimmer@sgi.com, wangnan0@huawei.com, vdavydov@parallels.com, toshi.kani@hp.com, phacht@linux.vnet.ibm.com, tj@kernel.org, kirill.shutemov@linux.intel.com, riel@redhat.com, luto@amacapital.net, hpa@linux.intel.com, aarcange@redhat.com, qiuxishi@huawei.com, mgorman@suse.de, rientjes@google.com, hannes@cmpxchg.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, tangchen@cn.fujitsu.com, stable@vger.kernel.org.#.3.16+ When memory is hot-added, all the memory is in offline state. So clear all zones' present_pages because they will be updated in online_pages() and offline_pages(). Otherwise, /proc/zoneinfo will corrupt: When the memory of node2 is offline: # cat /proc/zoneinfo ...... Node 2, zone Movable ...... spanned 8388608 present 8388608 managed 0 When we online memory on node2: # cat /proc/zoneinfo ...... Node 2, zone Movable ...... spanned 8388608 present 16777216 managed 8388608 Signed-off-by: Tang Chen Reviewed-by: Yasuaki Ishimatsu Cc: stable@vger.kernel.org # 3.16+ --- mm/memory_hotplug.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 8aba12b..d0c9b7c 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1067,6 +1067,16 @@ out: } #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */ +static void reset_node_present_pages(pg_data_t *pgdat) +{ + struct zone *z; + + for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++) + z->present_pages = 0; + + pgdat->node_present_pages = 0; +} + /* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start) { @@ -1105,6 +1115,13 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start) */ reset_node_managed_pages(pgdat); + /* + * When memory is hot-added, all the memory is in offline state. So + * clear all zones' present_pages because they will be updated in + * online_pages() and offline_pages(). + */ + reset_node_present_pages(pgdat); + return pgdat; } -- 1.8.3.1 -- 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