Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752505AbaKLIiI (ORCPT ); Wed, 12 Nov 2014 03:38:08 -0500 Received: from cn.fujitsu.com ([59.151.112.132]:34350 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752397AbaKLIiG (ORCPT ); Wed, 12 Nov 2014 03:38:06 -0500 X-IronPort-AV: E=Sophos;i="5.04,848,1406563200"; d="scan'208";a="43261153" From: Tang Chen To: , , , , , , , , , , , , , , , , , , , CC: , , , 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> X-Mailer: git-send-email 1.9.3 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 X-Originating-IP: [10.167.226.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/