From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759118Ab2FPAti (ORCPT ); Fri, 15 Jun 2012 20:49:38 -0400 Received: from e37.co.us.ibm.com ([32.97.110.158]:57993 "EHLO e37.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758984Ab2FPAth (ORCPT ); Fri, 15 Jun 2012 20:49:37 -0400 Date: Fri, 15 Jun 2012 17:49:31 -0700 From: "Paul E. McKenney" To: Steven Rostedt Cc: Josh Triplett , linux-kernel@vger.kernel.org, mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com, fweisbec@gmail.com, patches@linaro.org, "Paul E. McKenney" Subject: Re: [PATCH tip/core/rcu 09/15] rcu: Increasing rcu_barrier() concurrency Message-ID: <20120616004931.GU2389@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20120615210550.GA27506@linux.vnet.ibm.com> <1339794370-28119-1-git-send-email-paulmck@linux.vnet.ibm.com> <1339794370-28119-9-git-send-email-paulmck@linux.vnet.ibm.com> <20120615233151.GA7613@leaf> <1339806080.25903.68.camel@gandalf.stny.rr.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1339806080.25903.68.camel@gandalf.stny.rr.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12061600-7408-0000-0000-000005E5DA3D Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 15, 2012 at 08:21:20PM -0400, Steven Rostedt wrote: > On Fri, 2012-06-15 at 16:31 -0700, Josh Triplett wrote: > > > > > - smp_mb(); /* Prevent any prior operations from leaking in. */ > > > + /* > > > + * Ensure tht all prior references, including to ->n_barrier_done, > > > + * are ordered before the _rcu_barrier() machinery. > > > + */ > > > + smp_mb(); /* See above block comment. */ > > > > If checkpatch complains about the lack of a comment to the right of a > > barrier even when the barrier has a comment directly above it, that > > seems like a bug in checkpatch that needs fixing, to prevent developers > > from having to add noise like "See above block comment.". :) > > > Yuck yuck yuck yuck!!! > > > Really, checkpatch is not the golden rule. I've copied an old checkpatch > from something like 2.6.38 or so and use that today, where it was still > reasonable. I've long abandoned the latest checkpatch, as it causes too > many false positives. Or nazis like dictation. > > My rule of thumb is this. If what checkpatch tells you to do makes the > format either uglier, or look stupid, it's a good idea to ignore the > checkpatch complaint. > > I think in this case, you hit the latter. Heh. I have been doing this "/* See above block comment. */" thing for quite some time. ;-) Thanx, Paul