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From: John Baldwin <jhb@freebsd.org>
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Date: Tue, 25 Oct 2011 13:42:45 -0400
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	(bigwig.baldwin.cx); Tue, 25 Oct 2011 14:05:47 -0400 (EDT)
Cc: Luigi Rizzo <rizzo@iet.unipi.it>
Subject: Re: getting the cpuid for a userspace process ?
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On Tuesday, October 25, 2011 11:06:22 am Luigi Rizzo wrote:
> as the subject says... is there any way to get the current
> CPU id for a userspace process (of course,
> valid only at the time the function is called as the
> process might be arbitrarily moved while it runs)

Not from userland, no.  On x86 you can use cpuid to fetch the APIC ID, but 
that does not map 1:1 to FreeBSD cpu IDs.

-- 
John Baldwin