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To: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Linus Torvalds <torvalds@osdl.org>, Ingo Molnar <mingo@elte.hu>,
       linux-kernel@vger.kernel.org
Subject: Re: [RFC, patch] i386: vgetcpu(), take 2
References: <200606210329_MC3-1-C305-E008@compuserve.com>
From: Andi Kleen <ak@suse.de>
Date: 21 Jun 2006 11:26:06 +0200
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Chuck Ebbert <76306.1226@compuserve.com> writes:

> Use a GDT entry's limit field to store per-cpu data for fast access
> from userspace, and provide a vsyscall to access the current CPU
> number stored there.

Just the CPU alone is useless - you want at least the node too in many
cases. Best you use the prototype I proposed earlier for x86-64.

-Andi