From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [v3,11/41] mips: reuse asm-generic/barrier.h Date: Tue, 26 Jan 2016 11:15:43 +0100 Message-ID: <20160126101543.GC6357@twins.programming.kicks-ass.net> References: <5696CF08.8080700@imgtec.com> <20160114121449.GC15828@arm.com> <5697F6D2.60409@imgtec.com> <20160114203430.GC3818@linux.vnet.ibm.com> <56980C91.1010403@imgtec.com> <20160114212913.GF3818@linux.vnet.ibm.com> <20160115085554.GF3421@worktop> <20160115173912.GU3818@linux.vnet.ibm.com> <20160125180234.GA26732@arm.com> <20160126061211.GK4503@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20160126061211.GK4503@linux.vnet.ibm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: "Paul E. McKenney" Cc: linux-mips@linux-mips.org, linux-ia64@vger.kernel.org, "Michael S. Tsirkin" , Will Deacon , virtualization@lists.linux-foundation.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Ingo Molnar , linux-arch@vger.kernel.org, linux-s390@vger.kernel.org, Russell King - ARM Linux , user-mode-linux-devel@lists.sourceforge.net, linux-sh@vger.kernel.org, Michael Ellerman , x86@kernel.org, xen-devel@lists.xenproject.org, Ingo Molnar , linux-xtensa@linux-xtensa.org, james.hogan@imgtec.com, Arnd Bergmann , Stefano Stabellini , adi-buildroot-devel@lists.sourceforge.net, Leonid Yegoshin , ddaney.cavm@gmail.com, Thomas Gleixner , linux-metag@vger.kernel.orgl List-Id: linux-arch.vger.kernel.org On Mon, Jan 25, 2016 at 10:12:11PM -0800, Paul E. McKenney wrote: > On Mon, Jan 25, 2016 at 06:02:34PM +0000, Will Deacon wrote: > > Thanks for having a go at this. I tried defining something axiomatically, > > but got stuck pretty quickly. In my scheme, I used "data-directed > > transitivity" instead of "local transitivity", since the latter seems to > > be a bit of a misnomer. > > I figured that "local" meant local to the CPUs participating in the > release-acquire chain. As opposed to smp_mb() chains where the ordering > is "global" as in visible to all CPUs, whether on the chain or not. > Does that help? That is in fact how I read and understood it. From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.9]:60907 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932284AbcAZKQc (ORCPT ); Tue, 26 Jan 2016 05:16:32 -0500 Date: Tue, 26 Jan 2016 11:15:43 +0100 From: Peter Zijlstra Subject: Re: [v3,11/41] mips: reuse asm-generic/barrier.h Message-ID: <20160126101543.GC6357@twins.programming.kicks-ass.net> References: <5696CF08.8080700@imgtec.com> <20160114121449.GC15828@arm.com> <5697F6D2.60409@imgtec.com> <20160114203430.GC3818@linux.vnet.ibm.com> <56980C91.1010403@imgtec.com> <20160114212913.GF3818@linux.vnet.ibm.com> <20160115085554.GF3421@worktop> <20160115173912.GU3818@linux.vnet.ibm.com> <20160125180234.GA26732@arm.com> <20160126061211.GK4503@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160126061211.GK4503@linux.vnet.ibm.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: "Paul E. McKenney" Cc: Will Deacon , Leonid Yegoshin , "Michael S. Tsirkin" , linux-kernel@vger.kernel.org, Arnd Bergmann , linux-arch@vger.kernel.org, Andrew Cooper , Russell King - ARM Linux , virtualization@lists.linux-foundation.org, Stefano Stabellini , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Joe Perches , David Miller , linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-metag@vger.kernel.org, linux-mips@linux-mips.org, x86@kernel.org, user-mode-linux-devel@lists.sourceforge.net, adi-buildroot-devel@lists.sourceforge.net, linux-sh@vger.kernel.org, linux-xtensa@linux-xtensa.org, xen-devel@lists.xenproject.org, Ralf Baechle , Ingo Molnar , ddaney.cavm@gmail.com, james.hogan@imgtec.com, Michael Ellerman Message-ID: <20160126101543.o3q2REqfVtipmEgmq9uc-SjTmuX6Z0oxER9EeMM32N4@z> On Mon, Jan 25, 2016 at 10:12:11PM -0800, Paul E. McKenney wrote: > On Mon, Jan 25, 2016 at 06:02:34PM +0000, Will Deacon wrote: > > Thanks for having a go at this. I tried defining something axiomatically, > > but got stuck pretty quickly. In my scheme, I used "data-directed > > transitivity" instead of "local transitivity", since the latter seems to > > be a bit of a misnomer. > > I figured that "local" meant local to the CPUs participating in the > release-acquire chain. As opposed to smp_mb() chains where the ordering > is "global" as in visible to all CPUs, whether on the chain or not. > Does that help? That is in fact how I read and understood it.