From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1164563AbeBOXUI (ORCPT ); Thu, 15 Feb 2018 18:20:08 -0500 Received: from mail-wm0-f65.google.com ([74.125.82.65]:39093 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163785AbeBOXUG (ORCPT ); Thu, 15 Feb 2018 18:20:06 -0500 X-Google-Smtp-Source: AH8x227hQTg3yl0XqWGnbVaMML7cWsIcXiFnF1anbEi97OO3b2sTP6qYE3tpkecr7C2fNyRWHnNQnA== Date: Fri, 16 Feb 2018 00:19:58 +0100 From: Andrea Parri To: "Paul E. McKenney" Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, stern@rowland.harvard.edu, will.deacon@arm.com, peterz@infradead.org, boqun.feng@gmail.com, npiggin@gmail.com, dhowells@redhat.com, j.alglave@ucl.ac.uk, luc.maranget@inria.fr, akiyks@gmail.com Subject: Re: [PATCH RFC tip/lkmm 08/10] EXP Remove understore from smp_mb__before_atomic() workings Message-ID: <20180215231958.GA7422@andrea> References: <20180209141832.GA17505@linux.vnet.ibm.com> <1518186031-17997-8-git-send-email-paulmck@linux.vnet.ibm.com> <20180215223009.GA5460@andrea> <20180215224937.GD3617@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180215224937.GD3617@linux.vnet.ibm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 15, 2018 at 02:49:37PM -0800, Paul E. McKenney wrote: > On Thu, Feb 15, 2018 at 11:30:09PM +0100, Andrea Parri wrote: > > On Fri, Feb 09, 2018 at 06:20:29AM -0800, Paul E. McKenney wrote: > > > Signed-off-by: Paul E. McKenney > > > > nit: s/understore/underscore (a very understandable lapsus, BTW ;-) > > ;-) > > Will fix when squashing. > > > According to the cover letter, patches 8-10 of this series are intended > > to be squashed together; it could be useful to add a description then: > > the motivation for these changes might appear "trivial" today; months/ > > years from now? mmh, I can't put my finger on it ;-) > > Assuming we keep these patches, agreed. Something like this for the > aggregated single commit, perhaps: > > tools/memory-model: Convert underscores to hyphens > > Typical cat-language code uses hyphens for word separators in > identifiers, but several LKMM identifiers use underscores instead. > This commit therefore converts the underscores in the .bell and > .cat files for smp_mb__before_atomic(), smp_mb__after_atomic(), > and smp_mb__after_spinlock() to hyphens. > > > IMO, this descrition should also mention why this solution "is the way > > to go" (e.g., compare with the solution recently implemented by Akira). > > You lost me here. Or are you asking for a commit log similar to that > provided by Akira for his forward-port of Alan's unrelated patch? If > so, please see above. I was mainly thinking "but rb_dep..."; or you're also planning to rename this annotation and, maybe, the "rb-dep" relation (in order to avoid the conflict)? Andrea > > Thanx, Paul > > > Andrea > > > > > > > --- > > > tools/memory-model/linux-kernel.bell | 2 +- > > > tools/memory-model/linux-kernel.cat | 2 +- > > > tools/memory-model/linux-kernel.def | 2 +- > > > 3 files changed, 3 insertions(+), 3 deletions(-) > > > > > > diff --git a/tools/memory-model/linux-kernel.bell b/tools/memory-model/linux-kernel.bell > > > index b984bbda01a5..558bbef9e08a 100644 > > > --- a/tools/memory-model/linux-kernel.bell > > > +++ b/tools/memory-model/linux-kernel.bell > > > @@ -28,7 +28,7 @@ enum Barriers = 'wmb (*smp_wmb*) || > > > 'rcu-lock (*rcu_read_lock*) || > > > 'rcu-unlock (*rcu_read_unlock*) || > > > 'sync-rcu (*synchronize_rcu*) || > > > - 'before_atomic (*smp_mb__before_atomic*) || > > > + 'before-atomic (*smp_mb__before_atomic*) || > > > 'after_atomic (*smp_mb__after_atomic*) || > > > 'after_spinlock (*smp_mb__after_spinlock*) > > > instructions F[Barriers] > > > diff --git a/tools/memory-model/linux-kernel.cat b/tools/memory-model/linux-kernel.cat > > > index babe2b3b0bb3..31c08a44c088 100644 > > > --- a/tools/memory-model/linux-kernel.cat > > > +++ b/tools/memory-model/linux-kernel.cat > > > @@ -29,7 +29,7 @@ let rb-dep = [R] ; fencerel(Rb_dep) ; [R] > > > let rmb = [R \ Noreturn] ; fencerel(Rmb) ; [R \ Noreturn] > > > let wmb = [W] ; fencerel(Wmb) ; [W] > > > let mb = ([M] ; fencerel(Mb) ; [M]) | > > > - ([M] ; fencerel(Before_atomic) ; [RMW] ; po? ; [M]) | > > > + ([M] ; fencerel(Before-atomic) ; [RMW] ; po? ; [M]) | > > > ([M] ; po? ; [RMW] ; fencerel(After_atomic) ; [M]) | > > > ([M] ; po? ; [LKW] ; fencerel(After_spinlock) ; [M]) > > > let gp = po ; [Sync-rcu] ; po? > > > diff --git a/tools/memory-model/linux-kernel.def b/tools/memory-model/linux-kernel.def > > > index a397387f77cc..ff4b756f4a44 100644 > > > --- a/tools/memory-model/linux-kernel.def > > > +++ b/tools/memory-model/linux-kernel.def > > > @@ -21,7 +21,7 @@ smp_mb() { __fence{mb} ; } > > > smp_rmb() { __fence{rmb} ; } > > > smp_wmb() { __fence{wmb} ; } > > > smp_read_barrier_depends() { __fence{rb_dep}; } > > > -smp_mb__before_atomic() { __fence{before_atomic} ; } > > > +smp_mb__before_atomic() { __fence{before-atomic} ; } > > > smp_mb__after_atomic() { __fence{after_atomic} ; } > > > smp_mb__after_spinlock() { __fence{after_spinlock} ; } > > > > > > -- > > > 2.5.2 > > > > > >