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Date: Tue, 17 Sep 2002 11:35:16 -0700
From: Jun Sun <jsun@mvista.com>
To: Greg Lindahl <lindahl@keyresearch.com>
Cc: linux-mips@linux-mips.org, jsun@mvista.com
Subject: Re: [RFC] FPU context switch
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In-Reply-To: <20020917113136.A1890@wumpus.internal.keyresearch.com>; from lindahl@keyresearch.com on Tue, Sep 17, 2002 at 11:31:36AM -0700
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On Tue, Sep 17, 2002 at 11:31:36AM -0700, Greg Lindahl wrote:
> On Tue, Sep 17, 2002 at 11:04:23AM -0700, Jun Sun wrote:
> 
> > Currently I am leaning towards 2) or 3).  What is your opinion?
> 
> (1) and (2) are how other archs like Alpha and Itanium deal with
> this. I think (3) is likely to be painful to debug 

The good news is that I have already got it implemented and it
survived fairly stressful FPU tests.  :-)

> and maintain and
> won't win much. So I'd suggest (2).
>

Yes, 3) is a little harder to maitain.  I don't have much clue
as how much it will improve the performance in reality.
Presumably if there is only one FPU intensive process in the
system, it can improve a little bit.

Thanks for the feedback.

Jun