Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755258AbaKRTdK (ORCPT ); Tue, 18 Nov 2014 14:33:10 -0500 Received: from e35.co.us.ibm.com ([32.97.110.153]:56256 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755177AbaKRTdE (ORCPT ); Tue, 18 Nov 2014 14:33:04 -0500 Date: Tue, 18 Nov 2014 09:16:39 -0800 From: "Paul E. McKenney" To: Pranith Kumar Cc: Josh Triplett , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , "open list:READ-COPY UPDATE..." Subject: Re: [PATCH 08/16] rcupdate: Replace smp_read_barrier_depends() with lockless_dereference() Message-ID: <20141118171639.GV5050@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <1415906662-4576-1-git-send-email-bobby.prani@gmail.com> <1415906662-4576-9-git-send-email-bobby.prani@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1415906662-4576-9-git-send-email-bobby.prani@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14111819-0013-0000-0000-0000065862F0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 13, 2014 at 02:24:14PM -0500, Pranith Kumar wrote: > Recently lockless_dereference() was added which can be used in place of > hard-coding smp_read_barrier_depends(). The following PATCH makes the change. > > Signed-off-by: Pranith Kumar Queued for 3.20, thank you! I was wondering about your removing the "_" from "_________p1", but see that this allowed you to avoid the checkpatch.pl warning. ;-) Thanx, Paul > --- > include/linux/rcupdate.h | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h > index ed4f593..386ba28 100644 > --- a/include/linux/rcupdate.h > +++ b/include/linux/rcupdate.h > @@ -582,11 +582,11 @@ static inline void rcu_preempt_sleep_check(void) > }) > #define __rcu_dereference_check(p, c, space) \ > ({ \ > - typeof(*p) *_________p1 = (typeof(*p) *__force)ACCESS_ONCE(p); \ > + /* Dependency order vs. p above. */ \ > + typeof(*p) *________p1 = (typeof(*p) *__force)lockless_dereference(p); \ > rcu_lockdep_assert(c, "suspicious rcu_dereference_check() usage"); \ > rcu_dereference_sparse(p, space); \ > - smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ > - ((typeof(*p) __force __kernel *)(_________p1)); \ > + ((typeof(*p) __force __kernel *)(________p1)); \ > }) > #define __rcu_dereference_protected(p, c, space) \ > ({ \ > @@ -603,10 +603,10 @@ static inline void rcu_preempt_sleep_check(void) > }) > #define __rcu_dereference_index_check(p, c) \ > ({ \ > - typeof(p) _________p1 = ACCESS_ONCE(p); \ > + /* Dependency order vs. p above. */ \ > + typeof(p) _________p1 = lockless_dereference(p); \ > rcu_lockdep_assert(c, \ > "suspicious rcu_dereference_index_check() usage"); \ > - smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ > (_________p1); \ > }) > > -- > 1.9.1 > -- 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/