From patchwork Fri Jul 27 10:32:55 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wen Congyang X-Patchwork-Id: 1248121 Return-Path: X-Original-To: patchwork-linux-acpi@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id DC505DFFBF for ; Fri, 27 Jul 2012 10:27:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752268Ab2G0K15 (ORCPT ); Fri, 27 Jul 2012 06:27:57 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:48273 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752057Ab2G0K1z (ORCPT ); Fri, 27 Jul 2012 06:27:55 -0400 X-IronPort-AV: E=Sophos;i="4.77,666,1336320000"; d="scan'208";a="5496410" Received: from unknown (HELO tang.cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 27 Jul 2012 18:26:57 +0800 Received: from fnstmail02.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id q6RARqZC001523; Fri, 27 Jul 2012 18:27:53 +0800 Received: from [10.167.225.226] ([10.167.225.226]) by fnstmail02.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.3) with ESMTP id 2012072718282305-903870 ; Fri, 27 Jul 2012 18:28:23 +0800 Message-ID: <50126E57.2090501@cn.fujitsu.com> Date: Fri, 27 Jul 2012 18:32:55 +0800 From: Wen Congyang User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100413 Fedora/3.0.4-2.fc13 Thunderbird/3.0.4 MIME-Version: 1.0 To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-acpi@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, linux-ia64@vger.kernel.org, cmetcalf@tilera.com CC: rientjes@google.com, liuj97@gmail.com, len.brown@intel.com, benh@kernel.crashing.org, paulus@samba.org, cl@linux.com, minchan.kim@gmail.com, akpm@linux-foundation.org, kosaki.motohiro@jp.fujitsu.com, Yasuaki ISIMATU Subject: [RFC PATCH v5 13/19] memory-hotplug: check page type in get_page_bootmem References: <50126B83.3050201@cn.fujitsu.com> In-Reply-To: <50126B83.3050201@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/07/27 18:28:23, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2012/07/27 18:28:24, Serialize complete at 2012/07/27 18:28:24 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: Yasuaki Ishimatsu There is a possibility that get_page_bootmem() is called to the same page many times. So when get_page_bootmem is called to the same page, the function only increments page->_count. CC: David Rientjes CC: Jiang Liu CC: Len Brown CC: Benjamin Herrenschmidt CC: Paul Mackerras CC: Christoph Lameter Cc: Minchan Kim CC: Andrew Morton CC: KOSAKI Motohiro CC: Wen Congyang Signed-off-by: Yasuaki Ishimatsu --- mm/memory_hotplug.c | 15 +++++++++++---- 1 files changed, 11 insertions(+), 4 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 0c932e1..eae946b 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -95,10 +95,17 @@ static void release_memory_resource(struct resource *res) static void get_page_bootmem(unsigned long info, struct page *page, unsigned long type) { - page->lru.next = (struct list_head *) type; - SetPagePrivate(page); - set_page_private(page, info); - atomic_inc(&page->_count); + unsigned long page_type; + + page_type = (unsigned long) page->lru.next; + if (type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE || + type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE){ + page->lru.next = (struct list_head *) type; + SetPagePrivate(page); + set_page_private(page, info); + atomic_inc(&page->_count); + } else + atomic_inc(&page->_count); } /* reference to __meminit __free_pages_bootmem is valid