All of lore.kernel.org
 help / color / mirror / Atom feed
From: Huang Shijie <shijie8@gmail.com>
To: Mel Gorman <mel@csn.ul.ie>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
	akpm@linux-foundation.org, linux-mm@kvack.org
Subject: Re: [PATCH] mm : kill combined_idx
Date: Tue, 22 Dec 2009 11:11:53 +0800	[thread overview]
Message-ID: <4B3038F9.9040701@gmail.com> (raw)
In-Reply-To: <20091221194337.GA23345@csn.ul.ie>


>> Hmm...As far as I remember, this code design was for avoiding "if".
>> Is this compare+jump is better than add+xor ?
>>
>>     
>
> Agreed. It's not clear that a compare+jump is cheaper than the add+xor.
> How often it's the case that the page is the higher or lower half of the
> buddy would depend heavily on the allocation/free pattern making it
> hard, if not possible, to predict which is the more common case.
>
>   
ok. thanks a lot.

--
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:[~2009-12-22  3:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-21  3:32 [PATCH] mm : kill combined_idx Huang Shijie
2009-12-21  5:31 ` KAMEZAWA Hiroyuki
2009-12-21 19:43   ` Mel Gorman
2009-12-22  3:11     ` Huang Shijie [this message]

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=4B3038F9.9040701@gmail.com \
    --to=shijie8@gmail.com \
    --cc=akpm@linux-foundation.org \
    --cc=kamezawa.hiroyu@jp.fujitsu.com \
    --cc=linux-mm@kvack.org \
    --cc=mel@csn.ul.ie \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.