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Date: Thu, 20 Feb 2014 10:56:42 -0800
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Torvald Riegel <triegel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Will Deacon <will.deacon@arm.com>,
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Subject: Re: [RFC][PATCH 0/5] arch: atomic rework
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On Thu, Feb 20, 2014 at 07:44:32PM +0100, Torvald Riegel wrote:
> xagsmtp3.20140220184514.1789@bldgate.vnet.ibm.com
> X-Xagent-Gateway: bldgate.vnet.ibm.com (XAGSMTP3 at BLDGATE)
> 
> On Thu, 2014-02-20 at 10:11 -0800, Paul E. McKenney wrote:
> > But yes, the compiler guys would be extremely happy to simply drop
> > memory_order_consume from the standard, as it is the memory order
> > that they most love to hate.
> > 
> > Getting them to agree to any sort of peep-hole optimization semantics
> > for memory_order_consume is likely problematic.  
> 
> I wouldn't be so pessimistic about that.  If the transformations can be
> shown to be always correct in terms of the semantics specified in the
> standard, and if the performance win is sufficiently large, why not?  Of
> course, somebody has to volunteer to actually implement it :)

I guess that there is only one way to find out.  ;-)

							Thanx, Paul