Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762358AbXFASI7 (ORCPT ); Fri, 1 Jun 2007 14:08:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760165AbXFASIw (ORCPT ); Fri, 1 Jun 2007 14:08:52 -0400 Received: from mx1.redhat.com ([66.187.233.31]:32944 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758653AbXFASIv (ORCPT ); Fri, 1 Jun 2007 14:08:51 -0400 Date: Fri, 1 Jun 2007 14:08:07 -0400 From: Dave Jones To: Christoph Lameter Cc: young dave , linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org Subject: Re: [RFC 1/4] CONFIG_STABLE: Define it Message-ID: <20070601180807.GB7968@redhat.com> Mail-Followup-To: Dave Jones , Christoph Lameter , young dave , linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org References: <20070531002047.702473071@sgi.com> <20070531003012.302019683@sgi.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.14 (2007-02-12) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1903 Lines: 54 On Wed, May 30, 2007 at 05:49:56PM -0700, Christoph Lameter wrote: > On Thu, 31 May 2007, young dave wrote: > > > Hi Christoph, > > > > > Introduce CONFIG_STABLE to control checks only useful for development. > > > > What about control checks only as SLUB_DEBUG is set? > > Debug code is always included in all builds unless it is an embedded > system. Debug code is kept out of the hot path. > > Disabling SLUB_DEBUG should only be done for embedded systems. That is why > the option is in CONFIG_EMBEDDED. Something I'd really love to have is a CONFIG option to decide if slub_debug is set or not by default. The reasoning behind this is that during development of each Fedora release, I used to leave SLAB_DEBUG=y for months on end and catch all kinds of nasties. Now that I've switched it over to using slub, I ended up adding the ugly patch below, because otherwise, no-one would ever run with slub_debug and we'd miss out on all those lovely bugs. (I have 'make release' and 'make debug' targets which enable/disable this [and other] patches in the Fedora kernel). (Patch for illustration only, obviously not for applying). Unless someone beats me to it, I'll hack up a CONFIG option around this. Having that turned on if !CONFIG_STABLE would also be a win I think. Dave --- linux-2.6/mm/slub.c~ 2007-05-27 21:48:42.000000000 -0400 +++ linux-2.6/mm/slub.c 2007-05-27 21:51:22.000000000 -0400 @@ -323,7 +323,7 @@ static inline int slab_index(void *p, st /* * Debug settings: */ -static int slub_debug; +static int slub_debug = DEBUG_DEFAULT_FLAGS; static char *slub_debug_slabs; -- http://www.codemonkey.org.uk - 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/