LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Andi Kleen <andi@firstfloor.org>
To: Stephen Hemminger <shemminger@linux-foundation.org>
Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>,
	linux-kernel@vger.kernel.org, netdev@vger.kernel.org
Subject: Re: [RFC] div64_64 support
Date: 03 Mar 2007 03:31:52 +0100	[thread overview]
Message-ID: <p73slcnawh3.fsf@bingen.suse.de> (raw)
In-Reply-To: <20070226143127.5c74bec9@freekitty>

Stephen Hemminger <shemminger@linux-foundation.org> writes:

> Here is another way to handle the 64 bit divide case.
> It allows full 64 bit divide by adding the support routine
> GCC needs.

Not supplying that was intentional by Linus so that people
think twice (or more often) before they using such expensive
operations. A plain / looks too innocent.

Is it really needed by CUBIC anyways?  It uses it for getting
the cubic root, but the algorithm recommended by Hacker's Delight
(great book) doesn't use any divisions at all. Probably better 
to use a better algorithm without divisions.

-Andi

  parent reply	other threads:[~2007-03-03  1:32 UTC|newest]

Thread overview: 62+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-02-24  1:05 Stephen Hemminger
2007-02-24 16:19 ` Sami Farin
2007-02-26 19:28   ` Stephen Hemminger
2007-02-26 19:39     ` David Miller
2007-02-26 20:09 ` Jan Engelhardt
2007-02-26 21:28   ` Stephen Hemminger
2007-02-27  1:20     ` H. Peter Anvin
2007-02-27  3:45       ` Segher Boessenkool
2007-02-26 22:31   ` Stephen Hemminger
2007-02-26 23:02     ` Jan Engelhardt
2007-02-26 23:44       ` Stephen Hemminger
2007-02-27  0:05         ` Jan Engelhardt
2007-02-27  0:07           ` Stephen Hemminger
2007-02-27  0:14             ` Jan Engelhardt
2007-02-27  6:21     ` Dan Williams
2007-03-03  2:31     ` Andi Kleen [this message]
2007-03-05 23:57       ` Stephen Hemminger
2007-03-06  0:25         ` David Miller
2007-03-06 13:36           ` Andi Kleen
2007-03-06 14:04           ` [RFC] div64_64 support II Andi Kleen
2007-03-06 17:43             ` Dagfinn Ilmari Mannsåker
2007-03-06 18:25               ` David Miller
2007-03-06 18:48             ` H. Peter Anvin
2007-03-06 13:34         ` [RFC] div64_64 support Andi Kleen
2007-03-06 14:19           ` Eric Dumazet
2007-03-06 14:45             ` Andi Kleen
2007-03-06 15:10               ` Roland Kuhn
2007-03-06 18:29                 ` Stephen Hemminger
2007-03-06 19:48                   ` Andi Kleen
2007-03-06 20:04                     ` Stephen Hemminger
2007-03-06 21:53                   ` Sami Farin
2007-03-06 22:24                     ` Sami Farin
2007-03-07  0:00                       ` Stephen Hemminger
2007-03-07  0:05                         ` David Miller
2007-03-07  0:05                         ` Sami Farin
2007-03-07 16:11                       ` Chuck Ebbert
2007-03-07 18:32                         ` Sami Farin
2007-03-08 18:23                       ` asm volatile [Was: [RFC] div64_64 support] Sami Farin
2007-03-08 22:01                         ` asm volatile David Miller
2007-03-06 21:58                   ` [RFC] div64_64 support David Miller
2007-03-06 22:47                     ` [PATCH] tcp_cubic: faster cube root Stephen Hemminger
2007-03-06 22:58                       ` cube root benchmark code Stephen Hemminger
2007-03-07  6:08                         ` Update to " Willy Tarreau
2007-03-08  1:07                           ` [PATCH] tcp_cubic: use 32 bit math Stephen Hemminger
2007-03-08  2:55                             ` David Miller
2007-03-08  3:10                               ` Stephen Hemminger
2007-03-08  3:51                                 ` David Miller
2007-03-10 11:48                                   ` Willy Tarreau
2007-03-12 21:11                                     ` Stephen Hemminger
2007-03-13 20:50                                       ` Willy Tarreau
2007-03-21 18:54                                         ` Stephen Hemminger
2007-03-21 19:15                                           ` Willy Tarreau
2007-03-21 19:58                                             ` Stephen Hemminger
2007-03-21 20:15                                             ` [PATCH 1/2] div64_64 optimization Stephen Hemminger
2007-03-21 20:17                                               ` [PATCH 2/2] tcp: cubic optimization Stephen Hemminger
2007-03-22 19:11                                                 ` David Miller
2007-03-22 19:11                                               ` [PATCH 1/2] div64_64 optimization David Miller
2007-03-08  4:16                                 ` [PATCH] tcp_cubic: use 32 bit math Willy Tarreau
2007-03-07  4:20                       ` [PATCH] tcp_cubic: faster cube root David Miller
2007-03-07 12:12                         ` Andi Kleen
2007-03-07 19:33                           ` David Miller
2007-03-06 18:50               ` [RFC] div64_64 support 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=p73slcnawh3.fsf@bingen.suse.de \
    --to=andi@firstfloor.org \
    --cc=jengelh@linux01.gwdg.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=shemminger@linux-foundation.org \
    --subject='Re: [RFC] div64_64 support' \
    /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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).