From: Wu Fengguang <fengguang.wu@intel.com>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Zheng, Shaohui" <shaohui.zheng@intel.com>,
"linux-mm@kvack.org" <linux-mm@kvack.org>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"ak@linux.intel.com" <ak@linux.intel.com>,
"y-goto@jp.fujitsu.com" <y-goto@jp.fujitsu.com>,
Dave Hansen <haveblue@us.ibm.com>,
"x86@kernel.org" <x86@kernel.org>
Subject: Re: [ RESEND PATCH v3] Memory-Hotplug: Fix the bug on interface /dev/mem for 64-bit kernel
Date: Thu, 14 Jan 2010 21:24:51 +0800 [thread overview]
Message-ID: <20100114132451.GA2546@localhost> (raw)
In-Reply-To: <20100112170433.394be31b.kamezawa.hiroyu@jp.fujitsu.com>
Kame,
On Tue, Jan 12, 2010 at 05:04:33PM +0900, KAMEZAWA Hiroyuki wrote:
> 3 points...
> 1. I think this patch cannot be compiled in archs other than x86. Right ?
> IOW, please add static inline dummy...
Good catch!
> 2. pgdat->[start,end], totalram_pages etc...are updated at memory hotplug.
> Please place the hook nearby them.
arch/x86/mm/init_64.c:arch_add_memory() updates max_pfn_mapped, in
this sense it's equally OK to update max_pfn/max_low_pfn etc before
the call to arch_add_memory() ;)
> 3. I recommend you yo use memory hotplug notifier.
> If it's allowed, it will be cleaner.
Hmm, notifier is for _outsider_ subsystems. It smells a bit
overkill to do notifier _inside_ the hotplug code.
> It seems there are no strict ordering to update parameters this patch touches.
I tend to agree. That said, it does help keep our mind straight if we do it
in some logical order: max_pfn => max_pfn_mapped => totalram_pages etc.
Thanks,
Fengguang
--
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:[~2010-01-14 13:58 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-12 7:45 [ RESEND PATCH v3] Memory-Hotplug: Fix the bug on interface /dev/mem for 64-bit kernel Zheng, Shaohui
2010-01-12 8:04 ` KAMEZAWA Hiroyuki
2010-01-12 8:57 ` Zheng, Shaohui
2010-01-12 8:57 ` KAMEZAWA Hiroyuki
2010-01-12 9:05 ` Zheng, Shaohui
2010-01-12 13:17 ` Zheng, Shaohui
2010-01-14 13:24 ` Wu Fengguang [this message]
2010-01-14 14:08 ` Wu Fengguang
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=20100114132451.GA2546@localhost \
--to=fengguang.wu@intel.com \
--cc=ak@linux.intel.com \
--cc=akpm@linux-foundation.org \
--cc=haveblue@us.ibm.com \
--cc=kamezawa.hiroyu@jp.fujitsu.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=shaohui.zheng@intel.com \
--cc=x86@kernel.org \
--cc=y-goto@jp.fujitsu.com \
/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).