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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.