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Date: Thu, 04 Oct 2001 14:25:23 -0700 (PDT)
Message-Id: <20011004.142523.54186018.davem@redhat.com>
To: arjan@fenrus.demon.nl
Cc: kravetz@us.ibm.com, linux-kernel@vger.kernel.org
Subject: Re: Context switch times
From: "David S. Miller" <davem@redhat.com>
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	<E15pFor-0004sC-00@fenrus.demon.nl>
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   From: arjan@fenrus.demon.nl
   Date: Thu, 04 Oct 2001 22:14:13 +0100
   
   > Comments?
   
   2.4.x supports SSE on pentium III/athlons, so the SSE registers need to be
   saved/restored on a taskswitch as well.... that's not exactly free.

lat_ctx doesn't execute any FPU ops.  So at worst this happens once
on GLIBC program startup, but then never again.

This assumes I understand how lazy i387 restores work in the kernel
:-)

Franks a lot,
David S. Miller
davem@redhat.com
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