public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Andi Kleen <ak@suse.de>
To: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Stephane Eranian <eranian@hpl.hp.com>,
	Andrew Morton <akpm@osdl.org>,
	linux-kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/2] i386 TIF flags for debug regs and io bitmap in ctxsw
Date: Tue, 4 Jul 2006 23:47:00 +0200	[thread overview]
Message-ID: <200607042347.00598.ak@suse.de> (raw)
In-Reply-To: <200607041719_MC3-1-C420-EC5A@compuserve.com>

On Tuesday 04 July 2006 23:19, Chuck Ebbert wrote:
> In-Reply-To: <20060704072939.GC5902@frankl.hpl.hp.com>
>
> On Tue, 4 Jul 2006 00:29:39 -0700, Stephane Eranian wrote:
> > Following my discussion with Andi. Here is a patch that introduces
> > two new TIF flags to simplify the context switch code in __switch_to().
> > The idea is to minimize the number of cache lines accessed in the common
> > case, i.e., when neither the debug registers nor the I/O bitmap are used.
>
> I get a 5-10% speedup in task switch times with this patch.

That sounds too much. How did you measure it?

Note that lmbench tends to be unstable for this.

-Andi

  reply	other threads:[~2006-07-04 21:44 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-07-04 21:19 [PATCH 2/2] i386 TIF flags for debug regs and io bitmap in ctxsw Chuck Ebbert
2006-07-04 21:47 ` Andi Kleen [this message]
2006-07-04 21:45   ` Stephane Eranian
2006-07-04 21:51 ` Stephane Eranian
  -- strict thread matches above, loose matches on Subject: below --
2006-07-05 11:44 Chuck Ebbert
2006-07-04  7:29 Stephane Eranian

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=200607042347.00598.ak@suse.de \
    --to=ak@suse.de \
    --cc=76306.1226@compuserve.com \
    --cc=akpm@osdl.org \
    --cc=eranian@hpl.hp.com \
    --cc=linux-kernel@vger.kernel.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