From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755155AbbKCQOm (ORCPT ); Tue, 3 Nov 2015 11:14:42 -0500 Received: from mail-qk0-f173.google.com ([209.85.220.173]:35632 "EHLO mail-qk0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932221AbbKCQOA convert rfc822-to-8bit (ORCPT ); Tue, 3 Nov 2015 11:14:00 -0500 Message-ID: <5638dd45.4aed8c0a.b4962.ffffe94a@mx.google.com> Date: Tue, 03 Nov 2015 08:13:57 -0800 (PST) From: Yasuaki Ishimatsu To: Changsheng Liu Cc: , , , , , , , , Changsheng Liu Subject: Re: [PATCH V5] mm: memory hot-add: memory can not be added to movable zone defaultly In-Reply-To: <1442303398-45536-1-git-send-email-liuchangsheng@inspur.com> References: <9e3e1a14aae1a1d86cbe0ac245fa7356@s.corp-email.com> <1442303398-45536-1-git-send-email-liuchangsheng@inspur.com> X-Mailer: Sylpheed 3.4.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Changsheng, According to the following thread, Tang has no objection to change kernel behavior since udev cannot online memory as movable. https://lkml.org/lkml/2015/10/21/159 So how about reposting the v5 patch? I have a comment about the patch. Please see below. On Tue, 15 Sep 2015 03:49:58 -0400 Changsheng Liu wrote: > From: Changsheng Liu > > After the user config CONFIG_MOVABLE_NODE and movable_node kernel option, > When the memory is hot added, should_add_memory_movable() return 0 > because all zones including movable zone are empty, > so the memory that was hot added will be added to the normal zone > and the normal zone will be created firstly. > But we want the whole node to be added to movable zone defaultly. > > So we change should_add_memory_movable(): if the user config > CONFIG_MOVABLE_NODE and movable_node kernel option > it will always return 1 and all zones is empty at the same time, > so that the movable zone will be created firstly > and then the whole node will be added to movable zone defaultly. > If we want the node to be added to normal zone, > we can do it as follows: > "echo online_kernel > /sys/devices/system/memory/memoryXXX/state" > > Signed-off-by: Xiaofeng Yan > Signed-off-by: Changsheng Liu > Tested-by: Dongdong Fan > --- > 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 26fbba7..d39dbb0 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1190,6 +1190,9 @@ static int check_hotplug_memory_range(u64 start, u64 size) > /* > * If movable zone has already been setup, newly added memory should be check. > * If its address is higher than movable zone, it should be added as movable. > + * And if system boots up with movable_node and config CONFIG_MOVABLE_NOD and > + * added memory does not overlap the zone before MOVABLE_ZONE, > + * the memory is added as movable > * Without this check, movable zone may overlap with other zone. > */ > static int should_add_memory_movable(int nid, u64 start, u64 size) > @@ -1197,6 +1200,11 @@ static int should_add_memory_movable(int nid, u64 start, u64 size) > unsigned long start_pfn = start >> PAGE_SHIFT; > pg_data_t *pgdat = NODE_DATA(nid); > struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE; > + struct zone *pre_zone = pgdat->node_zones + (ZONE_MOVABLE - 1); > + > + if (movable_node_is_enabled() > + && zone_end_pfn(pre_zone) <= start_pfn) > + return 1; if (movable_node_is_enabled() && (zone_end_pfn(pre_zone) <= start_pfn)) Thanks, Yasuaki Ishimatsu > > if (zone_is_empty(movable_zone)) > return 0; > -- > 1.7.1 >