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Date: Mon, 10 Feb 2014 11:49:29 +0000
From: Will Deacon <will.deacon@arm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Torvald Riegel <triegel@redhat.com>,
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Subject: Re: [RFC][PATCH 0/5] arch: atomic rework
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On Mon, Feb 10, 2014 at 11:48:13AM +0000, Peter Zijlstra wrote:
> On Fri, Feb 07, 2014 at 10:02:16AM -0800, Paul E. McKenney wrote:
> > As near as I can tell, compiler writers hate the idea of prohibiting
> > speculative-store optimizations because it requires them to introduce
> > both control and data dependency tracking into their compilers.  Many of
> > them seem to hate dependency tracking with a purple passion.  At least,
> > such a hatred would go a long way towards explaining the incomplete
> > and high-overhead implementations of memory_order_consume, the long
> > and successful use of idioms based on the memory_order_consume pattern
> > notwithstanding [*].  ;-)
> 
> Just tell them that because the hardware provides control dependencies
> we actually use and rely on them.

s/control/address/ ?

Will