From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937722AbYEUVOv (ORCPT ); Wed, 21 May 2008 17:14:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S937401AbYEUVMI (ORCPT ); Wed, 21 May 2008 17:12:08 -0400 Received: from relay2.sgi.com ([192.48.171.30]:44367 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S937537AbYEUVMF (ORCPT ); Wed, 21 May 2008 17:12:05 -0400 Date: Wed, 21 May 2008 14:12:01 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Pekka Enberg cc: Matt Mackall , linux-kernel@vger.kernel.org, lethal@linux-sh.org, dhowells@redhat.com Subject: Re: [RFC/PATCH 3/3] SLOB: make ksize() more strict for page allocator pass-through In-Reply-To: <483473EA.40901@cs.helsinki.fi> Message-ID: References: <1211396840.18026.276.camel@calx> <483473EA.40901@cs.helsinki.fi> 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 On Wed, 21 May 2008, Pekka Enberg wrote: > Matt Mackall wrote: > > We already know users (ie nommu memory usage reporting) are abusing this > > interface. Making them blow up is unnecessary. Just give them wrong > > answers. Issuing a warning might be a good idea for debugging. > > But kobjsize() never calls ksize() with SLOB as it doesn't set PageSlab. Or > are you talking about something else here? > > Matt Mackall wrote: > > Second, I'd prefer to keep this sort of debugging code out of SLOB. > > SLUB is much better suited to debugging allocator abuse. > > Fair enough. I'll drop the patch. I also would prefer to keep this out of SLUB. Set/Clear PageSlab dirties the cacheline and it forces the unlining of kmalloc_large.