Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1954661AbdDYVAl (ORCPT <rfc822;w@1wt.eu>);
        Tue, 25 Apr 2017 17:00:41 -0400
Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:47617 "EHLO
        mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK)
        by vger.kernel.org with ESMTP id S1951456AbdDYVAa (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Tue, 25 Apr 2017 17:00:30 -0400
Date: Tue, 25 Apr 2017 14:00:24 -0700
From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: Joe Perches <joe@perches.com>
Cc: linux-kernel@vger.kernel.org, mingo@kernel.org, jiangshanlai@gmail.com,
        dipankar@in.ibm.com, akpm@linux-foundation.org,
        mathieu.desnoyers@efficios.com, josh@joshtriplett.org,
        tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org,
        dhowells@redhat.com, edumazet@google.com, fweisbec@gmail.com,
        oleg@redhat.com, bobby.prani@gmail.com
Subject: Re: [PATCH v3 tip/core/rcu 05/40] rcu: Semicolon inside RCU_TRACE()
 for rcu.h
Reply-To: paulmck@linux.vnet.ibm.com
References: <20170419165805.GB10874@linux.vnet.ibm.com>
 <1492621117-13939-5-git-send-email-paulmck@linux.vnet.ibm.com>
 <1492623683.8661.63.camel@perches.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1492623683.8661.63.camel@perches.com>
User-Agent: Mutt/1.5.21 (2010-09-15)
X-TM-AS-GCONF: 00
x-cbid: 17042521-0052-0000-0000-000001E641A0
X-IBM-SpamModules-Scores: 
X-IBM-SpamModules-Versions: BY=3.00006973; HX=3.00000240; KW=3.00000007;
 PH=3.00000004; SC=3.00000208; SDB=6.00852409; UDB=6.00421341; IPR=6.00631247;
 BA=6.00005312; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000;
 ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015175; XFM=3.00000013;
 UTC=2017-04-25 21:00:28
X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused
x-cbparentid: 17042521-0053-0000-0000-0000503C95A3
Message-Id: <20170425210024.GG3956@linux.vnet.ibm.com>
X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-04-25_15:,,
 signatures=0
X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0
 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam
 adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000
 definitions=main-1704250363
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 681
Lines: 15

On Wed, Apr 19, 2017 at 10:41:23AM -0700, Joe Perches wrote:
> On Wed, 2017-04-19 at 09:58 -0700, Paul E. McKenney wrote:
> > The current use of "RCU_TRACE(statement);" can cause odd bugs, especially
> > where "statement" is a local-variable declaration, as it can leave a
> > misplaced ";" in the source code.  This commit therefore converts these
> > to "RCU_TRACE(statement;)", which avoids the misplaced ";".
> 
> Perhaps instead the single RCU_TRACE macro should be split
> into RCU_TRACE_DECLARE and RCU_TRACE, and then RCU_TRACE
> should use do {} while (0)

Cute trick, but I am having a hard time getting very excited either way.
Thoughts from others?

							Thanx, Paul