linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: James Bottomley <James.bottomley@HansenPartnership.com>
To: Christoph Lameter <cl@linux.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Greg Thelen <gthelen@google.com>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
	Balbir Singh <bsingharora@gmail.com>,
	Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>,
	linux-arch@vger.kernel.org
Subject: Re: [PATCH] memcg: remove unneeded preempt_disable
Date: Thu, 25 Aug 2011 11:34:34 -0700	[thread overview]
Message-ID: <1e295500-5d1f-45dd-aa5b-3d2da2cf1a62@email.android.com> (raw)
In-Reply-To: <alpine.DEB.2.00.1108251206440.27407@router.home>



Christoph Lameter <cl@linux.com> wrote:

>On Thu, 25 Aug 2011, James Bottomley wrote:
>
>> >ARM seems to have these LDREX/STREX instructions for that purpose
>which
>> >seem to be used for generating atomic instructions without lockes. I
>> >guess
>> >other RISC architectures have similar means of doing it?
>>
>> Arm isn't really risc.  Most don't.  However even with ldrex/strex
>you need two instructions for rmw.
>
>Well then what is "really risc"? RISC is an old beaten down marketing
>term
>AFAICT and ARM claims it too.

Reduced Instruction Set Computer.  This is why we're unlikely to have complex atomic instructions: the principle of risc is that you build them up from basic ones.

James 
-- 
Sent from my Android phone with K-9 Mail. Please excuse my brevity and top posting.

--
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/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  reply	other threads:[~2011-08-25 18:34 UTC|newest]

Thread overview: 29+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-18  6:50 Greg Thelen
2011-08-18  6:52 ` KAMEZAWA Hiroyuki
2011-08-18  9:38 ` Johannes Weiner
2011-08-18 14:26   ` Valdis.Kletnieks
2011-08-18 14:41     ` Johannes Weiner
2011-08-18 18:27       ` Valdis.Kletnieks
2011-08-18 21:40 ` Andrew Morton
2011-08-19  0:00   ` Greg Thelen
2011-08-25 14:57   ` Peter Zijlstra
2011-08-25 15:11     ` Christoph Lameter
2011-08-25 16:20       ` James Bottomley
2011-08-25 16:31         ` Christoph Lameter
2011-08-25 16:34           ` James Bottomley
2011-08-25 17:07             ` Christoph Lameter
2011-08-25 18:34               ` James Bottomley [this message]
2011-08-25 18:46                 ` Christoph Lameter
2011-08-25 18:49                   ` Peter Zijlstra
2011-08-25 18:53                   ` Peter Zijlstra
2011-08-25 19:05                   ` Peter Zijlstra
2011-08-25 19:19                     ` Christoph Lameter
2011-08-25 22:56                       ` Peter Zijlstra
2011-08-25 19:29                   ` James Bottomley
2011-08-25 23:01                     ` Peter Zijlstra
2011-08-25 18:40           ` Peter Zijlstra
2011-09-06  9:58 ` Johannes Weiner
2011-09-06 10:04   ` KAMEZAWA Hiroyuki
2011-09-06 10:49     ` Johannes Weiner
2011-09-06 10:45       ` KAMEZAWA Hiroyuki
2011-09-06 18:04   ` Greg Thelen

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=1e295500-5d1f-45dd-aa5b-3d2da2cf1a62@email.android.com \
    --to=james.bottomley@hansenpartnership.com \
    --cc=akpm@linux-foundation.org \
    --cc=bsingharora@gmail.com \
    --cc=cl@linux.com \
    --cc=gthelen@google.com \
    --cc=kamezawa.hiroyu@jp.fujitsu.com \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=nishimura@mxp.nes.nec.co.jp \
    --cc=peterz@infradead.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