From: Andrew Morton <akpm@zip.com.au>
To: Russell King <rmk@arm.linux.org.uk>
Cc: Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [BK PATCH 2.5] Introduce 64-bit versions of PAGE_{CACHE_,}{MASK,ALIGN}
Date: Mon, 29 Jul 2002 11:32:56 -0700 [thread overview]
Message-ID: <3D458A58.FB15D5D0@zip.com.au> (raw)
In-Reply-To: 20020729102721.B23843@flint.arm.linux.org.uk
Russell King wrote:
>
> On Sun, Jul 28, 2002 at 05:10:48PM -0700, Andrew Morton wrote:
> > - Remove ->virtual, do page_address() via a hash. 4(ish) bytes saved.
>
> Hmmmmmmm. page_address() is already 5 loads (on ARM) if page->virtual
> isn't used. I'm seriously considering changing page_address() to cover
> the 3 cases more efficiently:
Well, one would want to keep the WANT_PAGE_VIRTUAL thing anyway.
btw, the usage of page_address() will quite possibly drop sharply soon
anyway. There's the patch floating about which permits atomic
kmaps to be held across copy_*_user. If that is adopted, things
like the pagecache IO routines won't do page_address() any more.
Said patch speeds up pagecache IO by between 0% and probably 30%.
It's the mystery surrounding this variation which is holding things
up.
-
next prev parent reply other threads:[~2002-07-29 18:31 UTC|newest]
Thread overview: 29+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-07-27 13:41 [BK PATCH 2.5] Introduce 64-bit versions of PAGE_{CACHE_,}{MASK,ALIGN} Anton Altaparmakov
2002-07-27 17:23 ` Andrew Morton
2002-07-28 17:53 ` Eric W. Biederman
2002-07-28 18:54 ` Anton Altaparmakov
2002-07-28 20:12 ` Eric W. Biederman
2002-07-28 23:26 ` Linus Torvalds
2002-07-29 0:10 ` Andrew Morton
2002-07-29 0:43 ` William Lee Irwin III
2002-07-29 0:56 ` Andrea Arcangeli
2002-07-29 1:04 ` William Lee Irwin III
2002-07-29 1:09 ` Rik van Riel
2002-07-29 2:14 ` Andrew Morton
2002-07-29 2:11 ` William Lee Irwin III
2002-07-29 2:18 ` Rik van Riel
2002-07-29 0:49 ` Andrea Arcangeli
2002-07-29 2:05 ` Andrew Morton
2002-07-29 2:09 ` William Lee Irwin III
2002-07-29 20:52 ` Andrea Arcangeli
2002-07-29 21:01 ` Andrew Morton
2002-07-29 21:31 ` Andrea Arcangeli
2002-07-29 21:46 ` Andrew Morton
2002-07-29 22:18 ` Andrea Arcangeli
2002-07-29 0:56 ` William Lee Irwin III
2002-07-29 1:36 ` Andrew Morton
2002-07-29 1:37 ` William Lee Irwin III
2002-07-29 9:27 ` Russell King
2002-07-29 18:32 ` Andrew Morton [this message]
[not found] <5.1.0.14.2.20020728193528.04336a80@pop.cus.cam.ac.uk.suse.lists.linux.kernel>
[not found] ` <Pine.LNX.4.44.0207281622350.8208-100000@home.transmeta.com.suse.lists.linux.kernel>
[not found] ` <3D448808.CF8D18BA@zip.com.au.suse.lists.linux.kernel>
[not found] ` <20020729004942.GL1201@dualathlon.random.suse.lists.linux.kernel>
[not found] ` <3D44A2DF.F751B564@zip.com.au.suse.lists.linux.kernel>
[not found] ` <20020729205211.GB1201@dualathlon.random.suse.lists.linux.kernel>
2002-07-30 13:44 ` Andi Kleen
2002-07-30 14:06 ` Rik van Riel
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=3D458A58.FB15D5D0@zip.com.au \
--to=akpm@zip.com.au \
--cc=linux-kernel@vger.kernel.org \
--cc=rmk@arm.linux.org.uk \
/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