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From: David Mosberger <davidm@napali.hpl.hp.com>
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Date: Thu, 14 Mar 2002 20:19:21 -0800
To: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>, davidm@hpl.hp.com, linux-kernel@vger.kernel.org,
        rth@twiddle.net
Subject: Re: [PATCH] 2.5.1-pre5: per-cpu areas 
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>>>>> On Fri, 15 Mar 2002 15:07:27 +1100, Rusty Russell <rusty@rustcorp.com.au> said:

  Rusty> Sorry, after thought, I've reverted to my original position.  the
  Rusty> original SMP per_cpu()/this_cpu() implementations were broken.

  Rusty> They must return an lvalue, otherwise they're useless for 50% of cases
  Rusty> (ie. assignment).  x86_64 can still use its own mechanism for
  Rusty> arch-specific per-cpu data, of course.

What's your position about someone taking the address of this_cpu(foo)
and passing it to another CPU?  IMO, the effect of this should be
allowed to be implementation-dependent.  If you agree, perhaps it
would be good to add a comment to this effect?

	--david