From: Jiang Liu <jiang.liu@huawei.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Tang Chen <tangchen@cn.fujitsu.com>,
wency@cn.fujitsu.com, linfeng@cn.fujitsu.com, rob@landley.net,
isimatu.yasuaki@jp.fujitsu.com, laijs@cn.fujitsu.com,
kosaki.motohiro@jp.fujitsu.com, minchan.kim@gmail.com,
mgorman@suse.de, rientjes@google.com, yinghai@kernel.org,
rusty@rustcorp.com.au, linux-kernel@vger.kernel.org,
linux-mm@kvack.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH 0/5] Add movablecore_map boot option.
Date: Tue, 20 Nov 2012 09:29:02 +0800 [thread overview]
Message-ID: <50AADCDE.1010301@huawei.com> (raw)
In-Reply-To: <20121119125325.ed1abba0.akpm@linux-foundation.org>
On 2012-11-20 4:53, Andrew Morton wrote:
> On Mon, 19 Nov 2012 22:27:21 +0800
> Tang Chen <tangchen@cn.fujitsu.com> wrote:
>
>> This patchset provide a boot option for user to specify ZONE_MOVABLE memory
>> map for each node in the system.
>>
>> movablecore_map=nn[KMG]@ss[KMG]
>>
>> This option make sure memory range from ss to ss+nn is movable memory.
>> 1) If the range is involved in a single node, then from ss to the end of
>> the node will be ZONE_MOVABLE.
>> 2) If the range covers two or more nodes, then from ss to the end of
>> the node will be ZONE_MOVABLE, and all the other nodes will only
>> have ZONE_MOVABLE.
>> 3) If no range is in the node, then the node will have no ZONE_MOVABLE
>> unless kernelcore or movablecore is specified.
>> 4) This option could be specified at most MAX_NUMNODES times.
>> 5) If kernelcore or movablecore is also specified, movablecore_map will have
>> higher priority to be satisfied.
>> 6) This option has no conflict with memmap option.
>
> This doesn't describe the problem which the patchset solves. I can
> kinda see where it's coming from, but it would be nice to have it all
> spelled out, please.
>
> - What is wrong with the kernel as it stands?
> - What are the possible ways of solving this?
> - Describe the chosen way, explain why it is superior to alternatives
>
> The amount of manual system configuration in this proposal looks quite
> high. Adding kernel boot parameters really is a last resort. Why was
> it unavoidable here?
Agree, manual configuration should be last resort.
We should ask help from BIOS to provide more help about hotplug functionality,
and it should work out of box on platforms with hotplug capabilities.
For CPU/memory/node hotplug, I feel the backward compatibility burden on OS
should be minor, so why don't ask help from BIOS to better support hotplug?
We could shape the interfaces between BIOS and OS to support system device
hotplug.
Thanks
Gerry
--
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: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
next prev parent reply other threads:[~2012-11-20 1:30 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-11-19 14:27 [PATCH 0/5] Add movablecore_map boot option Tang Chen
2012-11-19 14:27 ` [PATCH 1/5] x86: Get pg_data_t's memory from other node Tang Chen
2012-11-21 5:46 ` Yasuaki Ishimatsu
2012-11-21 5:58 ` Tang Chen
2012-11-21 6:06 ` Yasuaki Ishimatsu
2012-11-19 14:27 ` [PATCH 2/5] page_alloc: Add movablecore_map boot option Tang Chen
2012-11-21 5:44 ` Yasuaki Ishimatsu
2012-11-21 6:00 ` Yasuaki Ishimatsu
2012-11-19 14:27 ` [PATCH 3/5] page_alloc: Sanitize zone_movable_pfn Tang Chen
2012-11-19 14:27 ` [PATCH 4/5] page_alloc: Make movablecore_map has higher priority Tang Chen
2012-11-19 14:27 ` [PATCH 5/5] page_alloc: Bootmem limit with movablecore_map Tang Chen
2012-11-19 20:53 ` [PATCH 0/5] Add movablecore_map boot option Andrew Morton
2012-11-20 1:29 ` Jiang Liu [this message]
2012-11-20 11:07 ` Yasuaki Ishimatsu
2012-11-20 11:25 ` Jaegeuk Hanse
2012-11-21 0:36 ` Yasuaki Ishimatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=50AADCDE.1010301@huawei.com \
--to=jiang.liu@huawei.com \
--cc=akpm@linux-foundation.org \
--cc=isimatu.yasuaki@jp.fujitsu.com \
--cc=kosaki.motohiro@jp.fujitsu.com \
--cc=laijs@cn.fujitsu.com \
--cc=linfeng@cn.fujitsu.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=minchan.kim@gmail.com \
--cc=rientjes@google.com \
--cc=rob@landley.net \
--cc=rusty@rustcorp.com.au \
--cc=tangchen@cn.fujitsu.com \
--cc=wency@cn.fujitsu.com \
--cc=yinghai@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).