From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qg0-f41.google.com (mail-qg0-f41.google.com [209.85.192.41]) by kanga.kvack.org (Postfix) with ESMTP id 3A9BF6B0254 for ; Fri, 28 Aug 2015 16:22:32 -0400 (EDT) Received: by qgeh99 with SMTP id h99so38045177qge.0 for ; Fri, 28 Aug 2015 13:22:32 -0700 (PDT) Received: from mail-qk0-x22e.google.com (mail-qk0-x22e.google.com. [2607:f8b0:400d:c09::22e]) by mx.google.com with ESMTPS id 140si8538123qhf.90.2015.08.28.13.22.31 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 28 Aug 2015 13:22:31 -0700 (PDT) Received: by qkbm65 with SMTP id m65so34893748qkb.2 for ; Fri, 28 Aug 2015 13:22:31 -0700 (PDT) Message-ID: <55e0c306.4521370a.5c130.ffffa456@mx.google.com> Date: Fri, 28 Aug 2015 13:22:30 -0700 (PDT) From: Yasuaki Ishimatsu Subject: Re: [PATCH V3] mm: memory hot-add: memory can not be added to movable zone defaultly In-Reply-To: <1440665641-3839-1-git-send-email-liuchangsheng@inspur.com> References: <1440665641-3839-1-git-send-email-liuchangsheng@inspur.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Changsheng Liu Cc: akpm@linux-foundation.org, isimatu.yasuaki@jp.fujitsu.com, vbabka@suse.cz, linux-mm@kvack.org, linux-kernel@vger.kernel.org, wunan@inspur.com, yanxiaofeng@inspur.com, fandd@inspur.com, Changsheng Liu On Thu, 27 Aug 2015 04:54:01 -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" > > If the memory is added to movable zone defaultly, > the user can offline it and add it to other zone again. > But if the memory is added to normal zone defaultly, > the user will not offline the memory used by kernel. > > Reviewed-by: Andrew Morton > Signed-off-by: Changsheng Liu i > Tested-by: Dongdong Fan > --- > mm/memory_hotplug.c | 3 +++ > 1 files changed, 3 insertions(+), 0 deletions(-) > > diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c > index 26fbba7..b5f14fa 100644 > --- a/mm/memory_hotplug.c > +++ b/mm/memory_hotplug.c > @@ -1198,6 +1198,9 @@ static int should_add_memory_movable(int nid, u64 start, u64 size) > pg_data_t *pgdat = NODE_DATA(nid); > struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE; > > + if (movable_node_is_enabled()) > + return 1; > + > if (zone_is_empty(movable_zone)) > return 0; Your patch cannot prevent from creating ZONE_MOVABLE before/in ZONE_NORAML. Please check that start PFN of hot added memory is after ZONE_NORAML. Thanks, Yasuaki Ishimatsu > > -- > 1.7.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org