Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755895AbcCWQTM (ORCPT ); Wed, 23 Mar 2016 12:19:12 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:60372 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755786AbcCWQTL (ORCPT ); Wed, 23 Mar 2016 12:19:11 -0400 X-IBM-Helo: d03dlp01.boulder.ibm.com X-IBM-MailFrom: paulmck@linux.vnet.ibm.com X-IBM-RcptTo: linux-doc@vger.kernel.org;linux-kernel@vger.kernel.org Date: Wed, 23 Mar 2016 09:19:12 -0700 From: "Paul E. McKenney" To: Davidlohr Bueso Cc: mingo@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Davidlohr Bueso Subject: Re: [PATCH] Documentation,barriers: Mention smp_cond_acquire() Message-ID: <20160323161912.GC4287@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <1458594439-29666-1-git-send-email-dave@stgolabs.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1458594439-29666-1-git-send-email-dave@stgolabs.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16032316-0021-0000-0000-00001B03330D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1437 Lines: 34 On Mon, Mar 21, 2016 at 02:07:19PM -0700, Davidlohr Bueso wrote: > ... do this next to smp_load_acquire when first mentioning > ACQUIRE. While this call is briefly explained and ctrl > dependencies are mentioned later, it does not hurt the reader. > > Signed-off-by: Davidlohr Bueso Queued for review, thank you, Davidlohr! Thanx, Paul > --- > Documentation/memory-barriers.txt | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt > index 3729cbe60e41..2b5ea9d01a8f 100644 > --- a/Documentation/memory-barriers.txt > +++ b/Documentation/memory-barriers.txt > @@ -430,8 +430,9 @@ And a couple of implicit varieties: > This acts as a one-way permeable barrier. It guarantees that all memory > 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 smp_load_acquire() > - operations. > + 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(). > > Memory operations that occur before an ACQUIRE operation may appear to > happen after it completes. > -- > 2.1.4 >