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Date: Wed, 08 Nov 2000 10:46:25 -0800
From: Reto Baettig <baettig@scs.ch>
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To: david <sector2@ihug.co.nz>
CC: Linux Kernel List <linux-kernel@vger.kernel.org>
Subject: Re: fpu now a must in kernel
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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>
> 
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