From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752574Ab3K0FY3 (ORCPT ); Wed, 27 Nov 2013 00:24:29 -0500 Received: from edison.jonmasters.org ([173.255.233.168]:41799 "EHLO edison.jonmasters.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751029Ab3K0FYC (ORCPT ); Wed, 27 Nov 2013 00:24:02 -0500 X-Greylist: delayed 1670 seconds by postgrey-1.27 at vger.kernel.org; Wed, 27 Nov 2013 00:24:02 EST Message-ID: <52957B5E.60701@jonmasters.org> Date: Tue, 26 Nov 2013 23:55:58 -0500 From: Jon Masters Organization: World Organi{s,z}ation of Broken Dreams User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130923 Thunderbird/17.0.9 MIME-Version: 1.0 To: paulmck@linux.vnet.ibm.com CC: tony.luck@intel.com, peterz@infradead.org, linux-kernel@vger.kernel.org References: <20131111171307.GA27002@linux.vnet.ibm.com> In-Reply-To: <20131111171307.GA27002@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 74.92.29.237 X-SA-Exim-Mail-From: jonathan@jonmasters.org Subject: Re: Does Itanium permit speculative stores? X-SA-Exim-Version: 4.2.1 (built Sun, 08 Nov 2009 07:31:22 +0000) X-SA-Exim-Scanned: Yes (on edison.jonmasters.org) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/11/2013 12:13 PM, Paul E. McKenney wrote: > Hello, Tony, > > Does Itanium permit speculative stores? For example, on Itanium what are > the permitted outcomes of the following litmus test, where both x and y > are initially zero? > > CPU 0 CPU 1 > > r1 = ACCESS_ONCE(x); r2 = ACCESS_ONCE(y); > if (r1) if (r2) > ACCESS_ONCE(y) = 1; ACCESS_ONCE(x) = 1; > > In particular, is the outcome (r1 == 1 && r2 == 1) possible on Itanium > given this litmus test? > > Thanx, Paul > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > Btw, I was reading through some UEFI docs and noticed a reference to "A Formal Specification of Intel Itanium Processor Family Memory Ordering", then remembered this thread. In case it's of use: http://www.intel.com/design/itanium/downloads/251429.htm Jon.