linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Hugh Dickins <hugh@veritas.com>
To: Nick Piggin <npiggin@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
	linux-arch@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux Memory Management List <linux-mm@kvack.org>
Subject: Re: [rfc] optimise unlock_page
Date: Sun, 13 May 2007 05:39:03 +0100 (BST)	[thread overview]
Message-ID: <Pine.LNX.4.64.0705130535410.3015@blonde.wat.veritas.com> (raw)
In-Reply-To: <20070513033210.GA3667@wotan.suse.de>

On Sun, 13 May 2007, Nick Piggin wrote:
> On Fri, May 11, 2007 at 02:15:03PM +0100, Hugh Dickins wrote:
> 
> > Hmm, well, I think that's fairly horrid, and would it even be
> > guaranteed to work on all architectures?  Playing with one char
> > of an unsigned long in one way, while playing with the whole of
> > the unsigned long in another way (bitops) sounds very dodgy to me.
> 
> Of course not, but they can just use a regular atomic word sized
> bitop. The problem with i386 is that its atomic ops also imply
> memory barriers that you obviously don't need on unlock.

But is it even a valid procedure on i386?

Hugh

--
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:[~2007-05-13  4:39 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20070508113709.GA19294@wotan.suse.de>
2007-05-08 11:40 ` Nick Piggin
2007-05-08 20:08   ` Hugh Dickins
2007-05-08 21:30   ` Benjamin Herrenschmidt
2007-05-08 22:41     ` Nick Piggin
2007-05-08 22:50       ` Nick Piggin
2007-05-09 19:33         ` Hugh Dickins
2007-05-09 21:21           ` Benjamin Herrenschmidt
2007-05-10  3:37           ` Nick Piggin
2007-05-10 19:14             ` Hugh Dickins
2007-05-11  8:54               ` Nick Piggin
2007-05-11 13:15                 ` Hugh Dickins
2007-05-13  3:32                   ` Nick Piggin
2007-05-13  4:39                     ` Hugh Dickins [this message]
2007-05-13  6:52                       ` Nick Piggin
2007-05-16 17:54                         ` Hugh Dickins
2007-05-16 18:18                           ` Nick Piggin
2007-05-16 19:28                             ` Hugh Dickins
2007-05-16 19:47                               ` Linus Torvalds
2007-05-17  6:27                                 ` Nick Piggin
2007-05-16 17:21                     ` Hugh Dickins
2007-05-16 17:38                       ` Nick Piggin
2007-05-08 12:13 ` David Howells
2007-05-08 22:35   ` Nick Piggin

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=Pine.LNX.4.64.0705130535410.3015@blonde.wat.veritas.com \
    --to=hugh@veritas.com \
    --cc=akpm@linux-foundation.org \
    --cc=benh@kernel.crashing.org \
    --cc=linux-arch@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=npiggin@suse.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