From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753908Ab3BULDc (ORCPT ); Thu, 21 Feb 2013 06:03:32 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:57852 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753816Ab3BULDZ (ORCPT ); Thu, 21 Feb 2013 06:03:25 -0500 X-IronPort-AV: E=Sophos;i="4.84,709,1355068800"; d="scan'208";a="6743571" From: Lin Feng To: akpm@linux-foundation.org, mgorman@suse.de, bcrl@kvack.org, viro@zeniv.linux.org.uk Cc: khlebnikov@openvz.org, walken@google.com, kamezawa.hiroyu@jp.fujitsu.com, minchan@kernel.org, riel@redhat.com, rientjes@google.com, isimatu.yasuaki@jp.fujitsu.com, wency@cn.fujitsu.com, laijs@cn.fujitsu.com, tangchen@cn.fujitsu.com, guz.fnst@cn.fujitsu.com, jiang.liu@huawei.com, zab@redhat.com, jmoyer@redhat.com, linux-mm@kvack.org, linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Lin Feng Subject: [PATCH V3 0/2] mm: hotplug: implement non-movable version of get_user_pages() to kill long-time pin pages Date: Thu, 21 Feb 2013 19:01:42 +0800 Message-Id: <1361444504-31888-1-git-send-email-linfeng@cn.fujitsu.com> X-Mailer: git-send-email 1.7.11.7 X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/02/21 19:02:38, Serialize by Router on mailserver/fnst(Release 8.5.3|September 15, 2011) at 2013/02/21 19:02:40, Serialize complete at 2013/02/21 19:02:40 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently get_user_pages() always tries to allocate pages from movable zone, as discussed in thread https://lkml.org/lkml/2012/11/29/69, in some case users of get_user_pages() is easy to pin user pages for a long time(for now we found that pages pinned as aio ring pages is such case), which is fatal for memory hotplug/remove framework. So the 1st patch introduces a new library function called get_user_pages_non_movable() to pin pages only from zone non-movable in memory. It's a wrapper of get_user_pages() but it try its best to make sure that all pages come from non-movable zone via additional page migration. While if migration fails, it will keep the base functionality of get_user_pages(). The 2nd patch gets around the aio ring pages can't be migrated bug caused by get_user_pages() via using the new function. It only works when configed with CONFIG_MEMORY_HOTREMOVE, otherwise it falls back to use the old version of get_user_pages(). --- ChangeLog v2->v3: Patch1: - Handle the hugepage and THP migration bug pointed out by Mel. - In response to the other review comments suggested by Mel. - Updated according to mm-tree. Patch2: - Updated according to mm-tree. ChangeLog v1->v2: Patch1: - Fix the negative return value bug pointed out by Andrew and other suggestions pointed out by Andrew and Jeff. Patch2: - Kill the CONFIG_MEMORY_HOTREMOVE dependence suggested by Jeff. --- Lin Feng (2): mm: hotplug: implement non-movable version of get_user_pages() called get_user_pages_non_movable() fs/aio.c: use get_user_pages_non_movable() to pin ring pages when support memory hotremove fs/aio.c | 4 +- include/linux/mm.h | 14 ++++++ include/linux/mmzone.h | 4 ++ mm/memory.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++ mm/page_isolation.c | 8 ++++ 5 files changed, 131 insertions(+), 2 deletions(-)