Messages in this thread |  | | Date | Thu, 6 Feb 1997 14:01:38 -0500 | From | "David S. Miller" <> | Subject | Re: MMX performance.... |
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Date: Thu, 6 Feb 1997 17:36:51 +0200 (EET) From: Hannu Savolainen <hannu@voxware.pp.fi>
Is it allowed to use FPU/MXX inside kernel? I recall that this is not possible since kernel doesn't save FPU state when swiching between kernel and user modes. Or am I just misunderstood this.
This issue was already hashed out. You must save and restore the fpu around the memcpy using the FPU, and therefore you weight whether or not to do the FPU based copy using the size of the area to memcopy.
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