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From: Andi Kleen <ak@suse.de>
To: Chuck Ebbert <76306.1226@compuserve.com>
Subject: Re: [RFC, patch] i386: vgetcpu()
Date: Tue, 20 Jun 2006 22:57:16 +0200
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On Tuesday 20 June 2006 22:25, Chuck Ebbert wrote:
> Use the limit field of a GDT entry to store the current CPU
> number for fast userspace access.  This still leaves 12 bits
> free for other information.

Nice trick. Maybe I'll even add that to the x86-64 implementation
if it's fast enough. Do you have numbers?

But it needs to be encapsulated in a wrapper I think. Just exposing
it to user space is the wrong way to do this.

-Andi