From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760253Ab3EXJjq (ORCPT ); Fri, 24 May 2013 05:39:46 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:47827 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1760172Ab3EXJh2 (ORCPT ); Fri, 24 May 2013 05:37:28 -0400 X-IronPort-AV: E=Sophos;i="4.87,734,1363104000"; d="scan'208";a="7355222" From: Tang Chen To: akpm@linux-foundation.org, mgorman@suse.de, mingo@redhat.com, hpa@zytor.com, minchan@kernel.org, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, yinghai@kernel.org, jiang.liu@huawei.com, tj@kernel.org, liwanp@linux.vnet.ibm.com, isimatu.yasuaki@jp.fujitsu.com, kamezawa.hiroyu@jp.fujitsu.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 0/4] Support hot-remove local pagetable pages. Date: Fri, 24 May 2013 17:30:03 +0800 Message-Id: <1369387807-17956-1-git-send-email-tangchen@cn.fujitsu.com> X-Mailer: git-send-email 1.7.10.1 X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/05/24 17:25:48, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/05/24 17:36:00, Serialize complete at 2013/05/24 17:36:00 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following patch-set from Yinghai allocates pagetables to local nodes. v1: https://lkml.org/lkml/2013/3/7/642 v2: https://lkml.org/lkml/2013/3/10/47 v3: https://lkml.org/lkml/2013/4/4/639 v4: https://lkml.org/lkml/2013/4/11/829 Since pagetable pages are used by the kernel, they cannot be offlined. As a result, they cannot be hot-remove. This patch fix this problem with the following solution: 1. Introduce a new bootmem type LOCA_NODE_DATAL, and register local pagetable pages as LOCA_NODE_DATAL by setting page->lru.next to LOCA_NODE_DATAL, just like we register SECTION_INFO pages. 2. Skip LOCA_NODE_DATAL pages in offline/online procedures. When the whole memory block they reside in is offlined, the kernel can still access the pagetables. (This changes the semantics of offline/online a little bit.) 3. Do not free LOCA_NODE_DATAL pages to buddy system because they were skipped when in offline/online procedures. The memory block they reside in could have been offlined. Anyway, this problem should be fixed. Any better idea is welcome. Tang Chen (4): bootmem, mem-hotplug: Register local pagetable pages with LOCAL_NODE_DATA when freeing bootmem. mem-hotplug: Skip LOCAL_NODE_DATA pages in memory offline procedure. mem-hotplug: Skip LOCAL_NODE_DATA pages in memory online procedure. mem-hotplug: Do not free LOCAL_NODE_DATA pages to buddy system in hot-remove procedure. arch/x86/mm/init_64.c | 2 + include/linux/memblock.h | 22 +++++++++++++++++ include/linux/memory_hotplug.h | 13 ++++++++- mm/memblock.c | 52 ++++++++++++++++++++++++++++++++++++++++ mm/memory_hotplug.c | 42 +++++++++++++++++++++++++++++++- mm/page_alloc.c | 18 ++++++++++++- mm/page_isolation.c | 6 ++++ 7 files changed, 150 insertions(+), 5 deletions(-)