From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S938323AbXG3GMM (ORCPT ); Mon, 30 Jul 2007 02:12:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932909AbXG3GL5 (ORCPT ); Mon, 30 Jul 2007 02:11:57 -0400 Received: from colo.lackof.org ([198.49.126.79]:48887 "EHLO colo.lackof.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932720AbXG3GL4 (ORCPT ); Mon, 30 Jul 2007 02:11:56 -0400 X-Greylist: delayed 1960 seconds by postgrey-1.27 at vger.kernel.org; Mon, 30 Jul 2007 02:11:56 EDT Date: Sun, 29 Jul 2007 23:39:09 -0600 From: Grant Grundler To: Yoann Padioleau Cc: kernel-janitors@vger.kernel.org, matthew@wil.cx, grundler@parisc-linux.org, kyle@parisc-linux.org, parisc-linux@parisc-linux.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 11/68] 0 -> NULL, for arch/parisc Message-ID: <20070730053909.GF21206@colo.lackof.org> References: <200707270945.LAA17250@ifs.emn.fr> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200707270945.LAA17250@ifs.emn.fr> X-Home-Page: http://www.parisc-linux.org/ User-Agent: Mutt/1.5.15+20070515 (2007-05-02) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 27, 2007 at 11:45:05AM +0200, Yoann Padioleau wrote: > > When comparing a pointer, it's clearer to compare it to NULL than to 0. ... > diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c > index 04c7e1d..16fccbe 100644 > --- a/arch/parisc/kernel/smp.c > +++ b/arch/parisc/kernel/smp.c > @@ -333,7 +333,7 @@ smp_call_function (void (*func) (void *i > > if (retry) { > spin_lock (&lock); > - while (smp_call_function_data != 0) > + while (smp_call_function_data != NULL) > barrier(); > } > else { Yoann, Thanks! I like comparing pointers to NULL since it makes it explicit we are dealing with a pointer and is consistent with the assignment to NULL later in the code. But I'd like the later comparisons of smp_call_function_data to be consistent with your suggestion above. Patch below adds another "!= NULL". thanks grant Signed-off-by: Grant Grundler diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c index 04c7e1d..c9ce659 100644 --- a/arch/parisc/kernel/smp.c +++ b/arch/parisc/kernel/smp.c @@ -333,12 +333,12 @@ smp_call_function (void (*func) (void *info), void *info, int retry, int wait) if (retry) { spin_lock (&lock); - while (smp_call_function_data != 0) + while (smp_call_function_data != NULL) barrier(); } else { spin_lock (&lock); - if (smp_call_function_data) { + if (smp_call_function_data != NULL) { spin_unlock (&lock); return -EBUSY; }