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Date: Sat, 26 Jan 2002 03:03:41 +0100
From: Andi Kleen <ak@suse.de>
To: Linus Torvalds <torvalds@transmeta.com>
Cc: Andi Kleen <ak@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] syscall latency improvement #1
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On Fri, Jan 25, 2002 at 05:53:57PM -0800, Linus Torvalds wrote:
> 
> On 26 Jan 2002, Andi Kleen wrote:
> >
> > It doesn't explain the Athlon speedups. On athlon cli is ~4 cycles.
> 
> .. and it probably serializes the instruction stream.

I have word from AMD engineering that it doesn't stall the pipeline
or serializes.

(I asked the question during the design of the x86-64 syscall code) 

-Andi
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