From: Andi Kleen <ak@suse.de>
Organization: SUSE Linux Products GmbH, Nuernberg, GF: Markus Rex, HRB 16746 (AG Nuernberg)
To: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: Intel Memory Ordering White Paper
Date: Sat, 8 Sep 2007 12:19:43 +0200
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
       Jesse Barnes <jesse.barnes@intel.com>, linux-kernel@vger.kernel.org
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On Friday 07 September 2007 21:57:35 Nick Piggin wrote:

> 
> > > Anyway, the lfence should be able to go away without so much trouble.
> >
> > You mean sfence? lfence in rmb is definitely needed.
> 
> I mean lfence in smp_rmb().

One point of rmb is to stop speculative loads and I don't think we 
can get that without lfence.

-Andi

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