From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754647Ab3EYC0i (ORCPT ); Fri, 24 May 2013 22:26:38 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:8205 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753612Ab3EYC0h (ORCPT ); Fri, 24 May 2013 22:26:37 -0400 Message-ID: <51A02074.3020202@huawei.com> Date: Sat, 25 May 2013 10:22:44 +0800 From: Jianguo Wu User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:12.0) Gecko/20120428 Thunderbird/12.0.1 MIME-Version: 1.0 To: Tang Chen CC: , , , , , , , , , , , , , , Subject: Re: [PATCH 4/4] mem-hotplug: Do not free LOCAL_NODE_DATA pages to buddy system in hot-remove procedure. References: <1369387807-17956-1-git-send-email-tangchen@cn.fujitsu.com> <1369387807-17956-5-git-send-email-tangchen@cn.fujitsu.com> In-Reply-To: <1369387807-17956-5-git-send-email-tangchen@cn.fujitsu.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.135.74.216] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2013/5/24 17:30, Tang Chen wrote: > In memory hot-remove procedure, we free pagetable pages to buddy system. > But for local pagetable pages, do not free them to buddy system because > they were skipped in offline procedure. The memory block they reside in > could have been offlined, and we won't offline it again. > > Signed-off-by: Tang Chen > --- > mm/memory_hotplug.c | 8 ++++++++ > 1 files changed, 8 insertions(+), 0 deletions(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 21d6fcb..c30e819 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -119,6 +119,14 @@ void __ref put_page_bootmem(struct page *page) > INIT_LIST_HEAD(&page->lru); > > /* > + * Do not free pages with local node kernel data (for now, just > + * local pagetables) to the buddy system because we skipped > + * these pages when offlining the corresponding block. > + */ > + if (type == LOCAL_NODE_DATA) > + return; Hi Tang, I think this should be check in free_pagetable(), like: diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 474e28f..08fe80e 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -725,7 +725,7 @@ static void __meminit free_pagetable(struct page *page, int order) if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) { while (nr_pages--) put_page_bootmem(page++); - } else + } else if (magic != LOCAL_NODE_DATA) __free_pages_bootmem(page, order); } else free_pages((unsigned long)page_address(page), order); Thanks, Jianguo Wu. > + > + /* > * Please refer to comment for __free_pages_bootmem() > * for why we serialize here. > */