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Date: Wed, 30 Oct 2013 21:33:46 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Victor Kaplansky <VICTORK@il.ibm.com>, Anton Blanchard <anton@samba.org>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux PPC dev <linuxppc-dev@ozlabs.org>,
        Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
        Michael Ellerman <michael@ellerman.id.au>,
        Michael Neuling <mikey@neuling.org>, Oleg Nesterov <oleg@redhat.com>
Subject: Re: perf events ring buffer memory barrier on powerpc
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On Wed, Oct 30, 2013 at 04:51:16PM +0100, Peter Zijlstra wrote:
> On Wed, Oct 30, 2013 at 03:28:54PM +0200, Victor Kaplansky wrote:
> > one of the authors of Documentation/memory-barriers.txt is on cc: list ;-)
> > 
> > Disclaimer: it is anyway impossible to prove lack of *any* problem.
> > 
> > Having said that, lets look into an example in
> > Documentation/circular-buffers.txt:
> 
> > 
> > We can see that authors of the document didn't put any memory barrier
> 
> Note that both documents have the same author list ;-)
> 
> Anyway, I didn't know about the circular thing, I suppose I should use
> CIRC_SPACE() thing :-)

Interesting that we didn't seem to supply a definition...  ;-)

							Thanx, Paul