linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Minchan Kim <minchan.kim@gmail.com>
To: Huang Shijie <shijie8@gmail.com>
Cc: akpm@linux-foundation.org, mel@csn.ul.ie, linux-mm@kvack.org,
	KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Subject: Re: [PATCH] mm : add check for the return value
Date: Mon, 4 Jan 2010 15:06:54 +0900	[thread overview]
Message-ID: <28c262361001032206m6b102f85wed64ae31fd5b06d5@mail.gmail.com> (raw)
In-Reply-To: <4B417A37.7060001@gmail.com>

On Mon, Jan 4, 2010 at 2:18 PM, Huang Shijie <shijie8@gmail.com> wrote:
>
>> I think the branch itself could not a big deal but 'likely'.
>>
>> Why I suggest is that now 'if (!page)' don't have 'likely'.
>> As you know, 'likely' make the code relocate for reducing code footprint.
>>
>> Why? It was just mistake or doesn't need it?
>>
>>
>
> I think the CPU will CACHE the `likely' code, and make it runs fast.

I think so.

>
> IMHO, "if (unlikely(page == NULL)) " is better then "if (!page)" ,just like
> the
> code in rmqueue_bulk().
>> I think Mel does know it.
>>
>>
>
> wait for Mel's response.

Yes.
Regardless of Kosaki's patch, there is a issue about likely/unlinkely usage.

>



-- 
Kind regards,
Minchan Kim

--
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>

  reply	other threads:[~2010-01-04  6:06 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-01-04  2:22 [PATCH] mm : add check for the return value Huang Shijie
2010-01-04  3:21 ` Minchan Kim
2010-01-04  4:10   ` shijie8
2010-01-04  4:48     ` Minchan Kim
2010-01-04  5:18       ` Huang Shijie
2010-01-04  6:06         ` Minchan Kim [this message]
2010-01-08 22:59           ` Andrew Morton
2010-01-04  5:52   ` [PATCH] page allocator: fix update NR_FREE_PAGES only as necessary KOSAKI Motohiro
2010-01-04  6:03     ` Minchan Kim
2010-01-04  6:11     ` Huang Shijie
2010-01-04  6:16       ` KOSAKI Motohiro
2010-01-04  9:35         ` Huang Shijie
2010-01-05  7:24           ` KOSAKI Motohiro
2010-01-04  9:58     ` Mel Gorman
2010-01-04 17:46       ` Christoph Lameter
2010-01-05  1:08       ` KOSAKI Motohiro
2010-01-08 23:02     ` Andrew Morton

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=28c262361001032206m6b102f85wed64ae31fd5b06d5@mail.gmail.com \
    --to=minchan.kim@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=kosaki.motohiro@jp.fujitsu.com \
    --cc=linux-mm@kvack.org \
    --cc=mel@csn.ul.ie \
    --cc=shijie8@gmail.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).