From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f48.google.com (mail-pa0-f48.google.com [209.85.220.48]) by kanga.kvack.org (Postfix) with ESMTP id 5EB616B0253 for ; Tue, 25 Aug 2015 07:49:38 -0400 (EDT) Received: by pacdd16 with SMTP id dd16so121886130pac.2 for ; Tue, 25 Aug 2015 04:49:38 -0700 (PDT) Received: from sg02.corpemail.net (sg02.corpemail.net. [128.199.154.28]) by mx.google.com with ESMTPS id zb2si32578226pbb.152.2015.08.25.04.49.36 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 25 Aug 2015 04:49:37 -0700 (PDT) Received: from bgp253.corp-email.cn ([112.65.243.253]) by sg02.corpemail.net ((B_Out)) with ESMTP (SSL) id NLX00032 for ; Tue, 25 Aug 2015 19:49:32 +0800 Subject: Re: [PATCH] Memory hot added,The memory can not been added to movable zone References: <1439972306-50845-1-git-send-email-liuchangsheng@inspur.com> <20150819165029.665b89d7ab3228185460172c@linux-foundation.org> <55D57071.1080901@inspur.com> <55db6d6d.82d1370a.dd0ff.6055@mx.google.com> <55DC4294.2020407@inspur.com> <55DC4DC3.30509@suse.cz> From: Changsheng Liu Message-ID: <55DC5641.1090903@inspur.com> Date: Tue, 25 Aug 2015 19:49:21 +0800 MIME-Version: 1.0 In-Reply-To: <55DC4DC3.30509@suse.cz> Content-Type: multipart/alternative; boundary="------------050001070409050300020603" Sender: owner-linux-mm@kvack.org List-ID: To: Vlastimil Babka , Yasuaki Ishimatsu , Andrew Morton Cc: isimatu.yasuaki@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, yanxiaofeng@inspur.com, Changsheng Liu --------------050001070409050300020603 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit a?? 2015/8/25 19:13, Vlastimil Babka a??e??: > On 08/25/2015 12:25 PM, Changsheng Liu wrote: >> Thanks very much for your review, I can move the memory from normal zone >> to movable zone succesfully. >> And thank you for let me understand the memory mechanism better. >> a?? 2015/8/25 3:15, Yasuaki Ishimatsu a??e??: > > So you agree to drop the patch from -mm? The patch using movable_node_is_enabled() will provide a more direct approach to add the hot-added memory to movable zone If we want to remove the whole node. >>> Hi >>> On Thu, 20 Aug 2015 14:15:13 +0800 >>> Changsheng Liu wrote: >>> >>>> Hi Andrew Morton: >>>> First, thanks very much for your review, I will update codes according >>>> to your suggestio >>>> >>>> a?? 2015/8/20 7:50, Andrew Morton a??e??: >>>>> On Wed, 19 Aug 2015 04:18:26 -0400 Changsheng Liu >>>>> wrote: >>>>> >>>>>> From: Changsheng Liu >>>>>> >>>>>> When memory hot added, the function should_add_memory_movable >>>>>> always return 0,because the movable zone is empty, >>>>>> so the memory that hot added will add to normal zone even if >>>>>> we want to remove the memory. >>>>>> So we change the function should_add_memory_movable,if the user >>>>>> config CONFIG_MOVABLE_NODE it will return 1 when >>>>>> movable zone is empty >>>>> I cleaned this up a bit: >>>>> >>>>> : Subject: mm: memory hot-add: memory can not been added to >>>>> movable zone >>>>> : >>>>> : When memory is hot added, should_add_memory_movable() always >>>>> returns 0 >>>>> : because the movable zone is empty, so the memory that was hot >>>>> added will >>>>> : add to the normal zone even if we want to remove the memory. >>>>> : >>>>> : So we change should_add_memory_movable(): if the user config >>>>> : CONFIG_MOVABLE_NODE it will return 1 when the movable zone is >>>>> empty. >>>>> >>>>> But I don't understand the "even if we want to remove the memory". >>>>> This is hot-add, not hot-remove. What do you mean here? >>>> After the system startup, we hot added one memory. After >>>> some time >>>> we wanted to hot remove the memroy that was hot added, >>>> but we could not offline some memory blocks successfully >>>> because >>>> the memory was added to normal zone defaultly and the value of the >>>> file >>>> named removable under some memory blocks is 0. >>> For this, we prepared online_movable. When memory is onlined by >>> online_movable, >>> the memory move from ZONE_NORMAL to ZONE_MOVABLE. >>> >>> Ex. >>> # echo online_movable > /sys/devices/system/memory/memoryXXX/state >>> >>> Thanks, >>> Yasuaki Ishimatsu >>> >>>> we checked the value of the file under some memory blocks as >>>> follows: >>>> "cat /sys/devices/system/memory/ memory***/removable" >>>> When memory being hot added we let the memory be added to >>>> movable >>>> zone, >>>> so we will be able to hot remove the memory that have been >>>> hot added >>>>>> --- a/mm/memory_hotplug.c >>>>>> +++ b/mm/memory_hotplug.c >>>>>> @@ -1198,9 +1198,13 @@ 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 (zone_is_empty(movable_zone)) >>>>>> + if (zone_is_empty(movable_zone)) { >>>>>> + #ifdef CONFIG_MOVABLE_NODE >>>>>> + return 1; >>>>>> + #else >>>>>> return 0; >>>>>> - >>>>>> + #endif >>>>>> + } >>>>>> if (movable_zone->zone_start_pfn <= start_pfn) >>>>>> return 1; >>>>> Cleaner: >>>>> >>>>> --- >>>>> a/mm/memory_hotplug.c~memory-hot-addedthe-memory-can-not-been-added-to-movable-zone-fix >>>>> +++ a/mm/memory_hotplug.c >>>>> @@ -1181,13 +1181,9 @@ static int should_add_memory_movable(int >>>>> pg_data_t *pgdat = NODE_DATA(nid); >>>>> struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE; >>>>> >>>>> - if (zone_is_empty(movable_zone)) { >>>>> - #ifdef CONFIG_MOVABLE_NODE >>>>> - return 1; >>>>> - #else >>>>> - return 0; >>>>> - #endif >>>>> - } >>>>> + if (zone_is_empty(movable_zone)) >>>>> + return IS_ENABLED(CONFIG_MOVABLE_NODE); >>>>> + >>>>> if (movable_zone->zone_start_pfn <= start_pfn) >>>>> return 1; >>>>> >>>>> _ >>>>> >>>>> . >>>>> >>> . >>> >> > > . > --------------050001070409050300020603 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: 8bit

a?? 2015/8/25 19:13, Vlastimil Babka a??e??:
On 08/25/2015 12:25 PM, Changsheng Liu wrote:
Thanks very much for your review, I can move the memory from normal zone
to movable zone succesfully.
And thank you for let me understand the memory mechanism better.
a?? 2015/8/25 3:15, Yasuaki Ishimatsu a??e??:

So you agree to drop the patch from -mm?
A A A The patch using movable_node_is_enabled() will provide a more direct approach to add the hot-added memory to movable zone If we want to remove the whole node.
Hi
On Thu, 20 Aug 2015 14:15:13 +0800
Changsheng Liu <liuchangsheng@inspur.com> wrote:

Hi Andrew Morton:
First, thanks very much for your review, I will update codes according
toA your suggestio

a?? 2015/8/20 7:50, Andrew Morton a??e??:
On Wed, 19 Aug 2015 04:18:26 -0400 Changsheng Liu <liuchangsheng@inspur.com> wrote:

From: Changsheng Liu <liuchangcheng@inspur.com>

When memory hot added, the function should_add_memory_movable
always return 0,because the movable zone is empty,
so the memory that hot added will add to normal zone even if
we want to remove the memory.
So we change the function should_add_memory_movable,if the user
config CONFIG_MOVABLE_NODE it will return 1 when
movable zone is empty
I cleaned this up a bit:

: Subject: mm: memory hot-add: memory can not been added to movable zone
:
: When memory is hot added, should_add_memory_movable() always returns 0
: because the movable zone is empty, so the memory that was hot added will
: add to the normal zone even if we want to remove the memory.
:
: So we change should_add_memory_movable(): if the user config
: CONFIG_MOVABLE_NODE it will return 1 when the movable zone is empty.

But I don't understand the "even if we want to remove the memory".
This is hot-add, not hot-remove.A What do you mean here?
A A A A A A After the system startup, we hot added one memory. After some time
we wanted to hot remove the memroy that was hot added,
A A A A A A but we could not offline some memory blocks successfully because
the memory was added to normal zone defaultly and the value of the file
A A A A A A named removable under some memory blocks is 0.
For this, we prepared online_movable. When memory is onlined by online_movable,
the memory move from ZONE_NORMAL to ZONE_MOVABLE.

Ex.
# echo online_movable > /sys/devices/system/memory/memoryXXX/state

Thanks,
Yasuaki Ishimatsu

A A A A A A we checked the value of the file under some memory blocks as follows:
A A A A A A "cat /sys/devices/system/memory/ memory***/removable"
A A A A A A When memory being hot added we let the memory be added to movable
zone,
A A A A A A so we will be able to hot remove the memory that have been hot added
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1198,9 +1198,13 @@ static int should_add_memory_movable(int nid, u64 start, u64 size)
A A A A A A A pg_data_t *pgdat = NODE_DATA(nid);
A A A A A A A struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE;

-A A A if (zone_is_empty(movable_zone))
+A A A if (zone_is_empty(movable_zone)) {
+A A A #ifdef CONFIG_MOVABLE_NODE
+A A A A A A A return 1;
+A A A #else
A A A A A A A A A A A return 0;
-
+A A A #endif
+A A A }
A A A A A A A if (movable_zone->zone_start_pfn <= start_pfn)
A A A A A A A A A A A return 1;
Cleaner:

--- a/mm/memory_hotplug.c~memory-hot-addedthe-memory-can-not-been-added-to-movable-zone-fix
+++ a/mm/memory_hotplug.c
@@ -1181,13 +1181,9 @@ static int should_add_memory_movable(int
A A A A A A A pg_data_t *pgdat = NODE_DATA(nid);
A A A A A A A struct zone *movable_zone = pgdat->node_zones + ZONE_MOVABLE;

-A A A if (zone_is_empty(movable_zone)) {
-A A A #ifdef CONFIG_MOVABLE_NODE
-A A A A A A A return 1;
-A A A #else
-A A A A A A A return 0;
-A A A #endif
-A A A }
+A A A if (zone_is_empty(movable_zone))
+A A A A A A A return IS_ENABLED(CONFIG_MOVABLE_NODE);
+
A A A A A A A if (movable_zone->zone_start_pfn <= start_pfn)
A A A A A A A A A A A return 1;

_

.

.



.


--------------050001070409050300020603-- -- 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