From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752965Ab2G0K17 (ORCPT ); Fri, 27 Jul 2012 06:27:59 -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" 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 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@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 -- 1.7.1