Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759319AbZFKOYs (ORCPT ); Thu, 11 Jun 2009 10:24:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751708AbZFKOYk (ORCPT ); Thu, 11 Jun 2009 10:24:40 -0400 Received: from smtp3.ultrahosting.com ([74.213.175.254]:36875 "EHLO smtp.ultrahosting.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751505AbZFKOYk (ORCPT ); Thu, 11 Jun 2009 10:24:40 -0400 Date: Thu, 11 Jun 2009 10:24:35 -0400 (EDT) From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Pekka Enberg cc: linux-kernel@vger.kernel.org, mel@csn.ul.ie, Larry.Finger@lwfinger.net Subject: Re: [PATCH 2/2] SLUB: Disable debugging if it increases the minimum page order In-Reply-To: <1244728824.17483.51.camel@penberg-laptop> Message-ID: References: <1244728824.17483.51.camel@penberg-laptop> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1373 Lines: 31 On Thu, 11 Jun 2009, Pekka Enberg wrote: > On Thu, 2009-06-11 at 09:43 -0400, Christoph Lameter wrote: > > We have had that with SLAB. NO! This leads to the situation that some > > slabs have debug on and some have not. You just do not know which. > > I do see your point but surely we don't want to use order 1 allocations > in the fall-back case for kmalloc-4096? Couldn't we just add a printk > saying that debug was disabled for the cache? After all, my patch is > much better than what SLAB does. If we are enabling global debugging then we are looking for memory corruption in *all* slab caches. Disabling debugging of some cache behind the scenes is bad even if this leads to order 1 allocations. We could refine the way to specify groups of slab caches that should have debugging on. > On Thu, 2009-06-11 at 09:43 -0400, Christoph Lameter wrote: > > Note that CONFIG_SLUB_DEBUG only enables the code to debug a slab. It does > > not enable debugging for each slab. CONFIG_SLUB_DEBUG_ON does that. > > True. Larry, do you have CONFIG_SLUB_DEBUG_ON enabled or are you passing > SLUB debugging options to the kernel? -- 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/