From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com (mail-pa0-f43.google.com [209.85.220.43]) by kanga.kvack.org (Postfix) with ESMTP id 00F886B0254 for ; Wed, 4 Nov 2015 03:24:32 -0500 (EST) Received: by padhx2 with SMTP id hx2so38395436pad.1 for ; Wed, 04 Nov 2015 00:24:31 -0800 (PST) Received: from unicom146.biz-email.net (unicom146.biz-email.net. [210.51.26.146]) by mx.google.com with ESMTPS id e1si430710pas.116.2015.11.04.00.24.29 for (version=TLS1 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 04 Nov 2015 00:24:31 -0800 (PST) From: liuchangsheng Subject: [PATCH V8] mm: memory hot-add: hot-added memory can not be added to movable zone by default Date: Wed, 4 Nov 2015 03:23:35 -0500 Message-ID: <1446625415-11941-1-git-send-email-liuchangsheng@inspur.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, isimatu.yasuaki@jp.fujitsu.com, vbabka@suse.cz, yasu.isimatu@gmail.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, wunan@inspur.com, yanxiaofeng@inspur.com, liuchangsheng@inspur.com, fandd@inspur.com, Wang Nan , Dave Hansen , Yinghai Lu , Tang Chen , Toshi Kani , Xishi Qiu After the user config CONFIG_MOVABLE_NODE, When the memory is hot added, should_add_memory_movable() return 0 because all zones including ZONE_MOVABLE are empty, so the memory that was hot added will be assigned to ZONE_NORMAL, and we need using the udev rules to online the memory automatically: SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online_movable" The memory block onlined by udev must be adjacent to ZONE_MOVABLE. The events of memory section are notified to udev asynchronously, so it can not ensure that the memory block onlined by udev is adjacent to ZONE_MOVABLE.So it can't ensure memory online always success. But we want the whole node to be added to ZONE_MOVABLE by default. So we change should_add_memory_movable(): if the user config CONFIG_MOVABLE_NODE and movable_node kernel option and the ZONE_NORMAL is empty or the pfn of the hot-added memory is after the end of the ZONE_NORMAL it will always return 1 and then the whole node will be added to ZONE_MOVABLE by default. If we want the node to be assigned to ZONE_NORMAL, we can do it as follows: "echo online_kernel > /sys/devices/system/memory/memoryXXX/state" Signed-off-by: liuchangsheng Signed-off-by: Xiaofeng Yan Tested-by: Dongdong Fan Reviewed-by: Cc: Wang Nan Cc: Dave Hansen Cc: Yinghai Lu Cc: Tang Chen Cc: Yasuaki Ishimatsu Cc: Toshi Kani Cc: Xishi Qiu --- mm/memory_hotplug.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index aa992e2..8617b9f 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1201,6 +1201,9 @@ 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) @@ -1208,6 +1211,10 @@ 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 (zone_is_empty(movable_zone)) return 0; -- 1.8.3.1 -- 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