public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: "H. Peter Anvin" <hpa@zytor.com>
To: Jan Beulich <jbeulich@novell.com>
Cc: mingo@elte.hu, tglx@linutronix.de, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: introduce and use percpu_inc()
Date: Wed, 21 Apr 2010 23:48:13 -0700	[thread overview]
Message-ID: <4BCFF12D.60007@zytor.com> (raw)
In-Reply-To: <4BCFFA1B020000780005CBAE@vpn.id2.novell.com>

On 04/21/2010 11:26 PM, Jan Beulich wrote:
> 
>> Keep in mind that although INC is smaller than ADD,
>> the former has flag dependencies that the latter doesn't...
> 
> Wasn't that a problem just on Pentium4-s, which when I submitted
> another related patch a couple of months back I was told would
> not be a primary target anymore?
> 

It doesn't look like it, from what I could tell after the abovementioned
conversation... I was wondering mostly how many bytes this saved across
the kernel.  If it saves a byte in one place it's not so interesting,
but if it is all over it might make more sense.

It bit much worse on P4 than on most other cores, though.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.


  reply	other threads:[~2010-04-22  6:48 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-04-22  6:26 [PATCH] x86: introduce and use percpu_inc() Jan Beulich
2010-04-22  6:48 ` H. Peter Anvin [this message]
2010-04-22 11:01   ` Jan Beulich
  -- strict thread matches above, loose matches on Subject: below --
2010-04-21 14:21 Jan Beulich
2010-04-21 17:56 ` H. Peter Anvin

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=4BCFF12D.60007@zytor.com \
    --to=hpa@zytor.com \
    --cc=jbeulich@novell.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=tglx@linutronix.de \
    /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