Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757164AbXI2S1v (ORCPT ); Sat, 29 Sep 2007 14:27:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754877AbXI2S1n (ORCPT ); Sat, 29 Sep 2007 14:27:43 -0400 Received: from pasmtpb.tele.dk ([80.160.77.98]:46081 "EHLO pasmtpB.tele.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754485AbXI2S1m (ORCPT ); Sat, 29 Sep 2007 14:27:42 -0400 Date: Sat, 29 Sep 2007 20:29:09 +0200 From: Sam Ravnborg To: Randy Dunlap Cc: Erez Zadok , torvalds@linux-foundation.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, "Kok, Auke" , Kyle Moffett , Jan Engelhardt , Adrian Bunk , roel <12o3l@tiscali.nl> Subject: Re: [PATCH 1/3] CodingStyle updates Message-ID: <20070929182909.GA19943@uranus.ravnborg.org> References: <11910151223214-git-send-email-ezk@cs.sunysb.edu> <11910151223447-git-send-email-ezk@cs.sunysb.edu> <20070929110129.307cbd9f.randy.dunlap@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070929110129.307cbd9f.randy.dunlap@oracle.com> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2486 Lines: 57 On Sat, Sep 29, 2007 at 11:01:29AM -0700, Randy Dunlap wrote: > On Fri, 28 Sep 2007 17:32:00 -0400 Erez Zadok wrote: > > > 1. Updates chapter 13 (printing kernel messages) to expand on the use of > > pr_debug()/pr_info(), what to avoid, and how to hook your debug code with > > kernel.h. > > > > Signed-off-by: Erez Zadok > > --- > > Documentation/CodingStyle | 88 +++++++++++++++++++++++++++++++++++++++++++- > > 1 files changed, 86 insertions(+), 2 deletions(-) > > > > diff --git a/Documentation/CodingStyle b/Documentation/CodingStyle > > index 7f1730f..00b29e4 100644 > > --- a/Documentation/CodingStyle > > +++ b/Documentation/CodingStyle > > @@ -643,8 +643,26 @@ Printing numbers in parentheses (%d) adds no value and should be avoided. > > There are a number of driver model diagnostic macros in > > which you should use to make sure messages are matched to the right device > > and driver, and are tagged with the right level: dev_err(), dev_warn(), > > -dev_info(), and so forth. For messages that aren't associated with a > > -particular device, defines pr_debug() and pr_info(). > > +dev_info(), and so forth. > > + > > +A number of people often like to define their own debugging printf's, > > +wrapping printk's in #ifdef's that get turned on only when subsystem > > +debugging is compiled in (e.g., dprintk, Dprintk, DPRINTK, etc.). Please > > +don't reinvent the wheel but use existing mechanisms. For messages that > > +aren't associated with a particular device, defines > > +pr_debug() and pr_info(); the latter two translate to printk(KERN_DEBUG) and > > +printk(KERN_INFO), respectively. However, to get pr_debug() to actually > > +emit the message, you'll need to turn on DEBUG in your code, which can be > > +done as follows in your subsystem Makefile: > > + > > +ifeq ($(CONFIG_WHATEVER_DEBUG),y) > > +EXTRA_CFLAGS += -DDEBUG > > +endif The abvoe hurst my eyes each time I see it. Lately I have considered extending the kbuild syntax a bit. Introducing ccflags-y asflags-y [with same functionality as the EXTRA_CFLAGS, EXTRA_AFLAGS] would allow us to do: ccflags-$(CONFIG_WHATEVER_DEBUG) := -DDEBUG Much nicer IMHO. Sam - 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/