From owner-freebsd-ia64@FreeBSD.ORG  Tue Jul 13 15:57:55 2004
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Date: Tue, 13 Jul 2004 08:57:54 -0700
From: Marcel Moolenaar <marcel@xcllnt.net>
To: "Yang M.M." <youngdream8039@hotmail.com>
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cc: freebsd-ia64@freebsd.org
Subject: Re: does FreeBSD have "per-CPU page" ?
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On Tue, Jul 13, 2004 at 02:54:59AM +0000, Yang M.M. wrote:
> Hi all,
> Linux/ia64 has a "per-CPU page" in region 5 just after "gate page". The 
> per-CPU page provides one page of CPU-local data,which is useful on MP 
> machines.
> My question is : does FreeBSD have such a page? If so, where is it? 

Yes and no. There is per-CPU data, but it's not necessarily a page
and definitely is not wired at a fixed virtual address.

The address of the per-CPU data is in pcpup. This happens to be
register 13 (TP). It is saved in ar.k4, from which pcpup (=r13)
is restored on entry into the kernel.

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel@xcllnt.net