From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: Question about DEC Alpha memory ordering Date: Mon, 13 Feb 2017 12:32:00 -0800 Message-ID: <20170213203200.GP30506@linux.vnet.ibm.com> References: <20170213183920.GA25191@linux.vnet.ibm.com> <20170213190931.GK30506@linux.vnet.ibm.com> <20170213192334.rjs5yq3gmw5cg7km@tower> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <20170213192334.rjs5yq3gmw5cg7km@tower> Sender: linux-alpha-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Michael Cree , bob smith , rth@twiddle.net, ink@jurassic.park.msu.ru, mattst88@gmail.com, stern@rowland.harvard.edu, j.alglave@ucl.ac.uk, luc.maranget@inria.fr, parri.andrea@gmail.com, will.deacon@arm.com, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org On Tue, Feb 14, 2017 at 08:23:34AM +1300, Michael Cree wrote: > Hi Paul, > > On Mon, Feb 13, 2017 at 11:09:31AM -0800, Paul E. McKenney wrote: > > On Mon, Feb 13, 2017 at 01:53:27PM -0500, bob smith wrote: > > > On 2/13/17 1:39 PM, Paul E. McKenney wrote: > > > > can real DEC Alpha hardware end up with both instances of "r1" > > > > having the value 1? > > > > > > I thought this question reminded me of something, so I found this: > > > > https://www.kernel.org/doc/Documentation/memory-barriers.txt > > > > > > and I pasted in the content - David Howells is one of the authors and > > > maybe that is why the question sort of reminded me. > > > > > > Maybe someone has an update but this is what was said then. > > > > Well, thank you for pointing me to this, but my question was intended to > > check whether or not the words I helped to write in memory-barriers.txt > > are in fact accurate. So if you have an SMP DEC Alpha system that you > > could provide remote access to, that would be very helpful! > > I'm that guy with an SMP Alpha system who met you at Linux Conference > Australia after your talk on memory barriers. I meant to get back to > you but tracking down a kernel bug and now a binutils/glibc bug has > got the better of my time. > > Feel free to email me personally to arrange remote access to an SMP > Alpha system, preferrably with a GPG signed message. Would you be willing to extend this offer to Andrea Parri (CCed)? He is the one who has run such tests in the past. Thanx, Paul