From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrea Parri Subject: Re: [PATCH] doc: Replace smp_cond_acquire() with smp_cond_load_acquire() Date: Tue, 10 Jul 2018 16:34:59 +0200 Message-ID: <20180710143459.GA10527@andrea> References: <1531216943-6382-1-git-send-email-andrea.parri@amarulasolutions.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1531216943-6382-1-git-send-email-andrea.parri@amarulasolutions.com> Sender: linux-kernel-owner@vger.kernel.org To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org Cc: Alan Stern , Will Deacon , Peter Zijlstra , Boqun Feng , Nicholas Piggin , David Howells , Jade Alglave , Luc Maranget , "Paul E. McKenney" , Akira Yokosawa , Daniel Lustig , Jonathan Corbet List-Id: linux-arch.vger.kernel.org On Tue, Jul 10, 2018 at 12:02:23PM +0200, Andrea Parri wrote: > Amend commit 1f03e8d2919270 ("locking/barriers: Replace smp_cond_acquire() > with smp_cond_load_acquire()") by updating the documentation accordingly. > > Signed-off-by: Andrea Parri > Cc: Alan Stern > Cc: Will Deacon > Cc: Peter Zijlstra > Cc: Boqun Feng > Cc: Nicholas Piggin > Cc: David Howells > Cc: Jade Alglave > Cc: Luc Maranget > Cc: "Paul E. McKenney" > Cc: Akira Yokosawa > Cc: Daniel Lustig > Cc: Jonathan Corbet > --- > Documentation/memory-barriers.txt | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt > index 0d8d7ef131e9a..987a4e6cc0cd8 100644 > --- a/Documentation/memory-barriers.txt > +++ b/Documentation/memory-barriers.txt > @@ -471,8 +471,8 @@ And a couple of implicit varieties: > operations after the ACQUIRE operation will appear to happen after the > ACQUIRE operation with respect to the other components of the system. > ACQUIRE operations include LOCK operations and both smp_load_acquire() > - and smp_cond_acquire() operations. The later builds the necessary ACQUIRE > - semantics from relying on a control dependency and smp_rmb(). > + and smp_cond_load_acquire() operations. The later builds the necessary > + ACQUIRE semantics from relying on a control dependency and smp_rmb(). Still not completely accurate: smp_rmb() would better be replaced by smp_acquire__after_ctrl_dep() (arm64 excluded). Mmh... I think I'll just remove that "The latter builds the [...]" and resend; thoughts? Andrea > > Memory operations that occur before an ACQUIRE operation may appear to > happen after it completes. > -- > 2.7.4 > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f68.google.com ([209.85.221.68]:34753 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933330AbeGJOfI (ORCPT ); Tue, 10 Jul 2018 10:35:08 -0400 Received: by mail-wr1-f68.google.com with SMTP id c13-v6so14840748wrt.1 for ; Tue, 10 Jul 2018 07:35:08 -0700 (PDT) Date: Tue, 10 Jul 2018 16:34:59 +0200 From: Andrea Parri Subject: Re: [PATCH] doc: Replace smp_cond_acquire() with smp_cond_load_acquire() Message-ID: <20180710143459.GA10527@andrea> References: <1531216943-6382-1-git-send-email-andrea.parri@amarulasolutions.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1531216943-6382-1-git-send-email-andrea.parri@amarulasolutions.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org Cc: Alan Stern , Will Deacon , Peter Zijlstra , Boqun Feng , Nicholas Piggin , David Howells , Jade Alglave , Luc Maranget , "Paul E. McKenney" , Akira Yokosawa , Daniel Lustig , Jonathan Corbet Message-ID: <20180710143459.IMIvK9SiMXvnLBaX9MjqkWFYHpsZ4p4t0NkRnf0VrCI@z> On Tue, Jul 10, 2018 at 12:02:23PM +0200, Andrea Parri wrote: > Amend commit 1f03e8d2919270 ("locking/barriers: Replace smp_cond_acquire() > with smp_cond_load_acquire()") by updating the documentation accordingly. > > Signed-off-by: Andrea Parri > Cc: Alan Stern > Cc: Will Deacon > Cc: Peter Zijlstra > Cc: Boqun Feng > Cc: Nicholas Piggin > Cc: David Howells > Cc: Jade Alglave > Cc: Luc Maranget > Cc: "Paul E. McKenney" > Cc: Akira Yokosawa > Cc: Daniel Lustig > Cc: Jonathan Corbet > --- > Documentation/memory-barriers.txt | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt > index 0d8d7ef131e9a..987a4e6cc0cd8 100644 > --- a/Documentation/memory-barriers.txt > +++ b/Documentation/memory-barriers.txt > @@ -471,8 +471,8 @@ And a couple of implicit varieties: > operations after the ACQUIRE operation will appear to happen after the > ACQUIRE operation with respect to the other components of the system. > ACQUIRE operations include LOCK operations and both smp_load_acquire() > - and smp_cond_acquire() operations. The later builds the necessary ACQUIRE > - semantics from relying on a control dependency and smp_rmb(). > + and smp_cond_load_acquire() operations. The later builds the necessary > + ACQUIRE semantics from relying on a control dependency and smp_rmb(). Still not completely accurate: smp_rmb() would better be replaced by smp_acquire__after_ctrl_dep() (arm64 excluded). Mmh... I think I'll just remove that "The latter builds the [...]" and resend; thoughts? Andrea > > Memory operations that occur before an ACQUIRE operation may appear to > happen after it completes. > -- > 2.7.4 >