public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Reto Baettig <baettig@scs.ch>
To: david <sector2@ihug.co.nz>
Cc: Linux Kernel List <linux-kernel@vger.kernel.org>
Subject: Re: fpu now a must in kernel
Date: Wed, 08 Nov 2000 10:46:25 -0800	[thread overview]
Message-ID: <3A099F81.81FD885@scs.ch> (raw)
In-Reply-To: <3A09E161.ACB11253@ihug.co.nz>

When you add it to the task switcher, it takes away a lot of cpu cycles
during each task switch and slows down your system. I think this was the
main idea behind _not_ saving those registers. IMHO, it does not make
sense to generally save these registers when nobody else but your driver
uses them. 

Good luck!

Reto

david wrote:
> 
> hi i need fast fpu in the kernel for my lexos work
> so how am i going to do it on the i386
> 
> 1 . can i add some save / restore code to the task swicher ( the right
> way )
>      so when it switchs from user to kernel task its saves the fpu state
> ?
> 
> 2 . put the save / restore code in my code (NOT! GOOD! i do not wont to
> do it this way it is not the right way)
> 
> so i have to use fpu in the kernel so its just how am i going to do it ?
> 
> thank you
> 
>     David Rundle <sector2@ihug.co.nz>
> 
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> Please read the FAQ at http://www.tux.org/lkml/
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

  reply	other threads:[~2000-11-08 23:51 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2000-11-08 23:27 fpu now a must in kernel david
2000-11-08 18:46 ` Reto Baettig [this message]
2000-11-09  0:45   ` David Lang
2000-11-08 23:39 ` Timur Tabi
2000-11-09 14:36 ` Andi Kleen
2000-11-09 18:00   ` George Anzinger

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=3A099F81.81FD885@scs.ch \
    --to=baettig@scs.ch \
    --cc=linux-kernel@vger.kernel.org \
    --cc=sector2@ihug.co.nz \
    /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