From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751674Ab1GTKOl (ORCPT ); Wed, 20 Jul 2011 06:14:41 -0400 Received: from ozlabs.org ([203.10.76.45]:32878 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751321Ab1GTKOj (ORCPT ); Wed, 20 Jul 2011 06:14:39 -0400 Date: Wed, 20 Jul 2011 20:14:36 +1000 From: Anton Blanchard To: Peter Zijlstra Cc: mahesh@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mingo@elte.hu, benh@kernel.crashing.org, torvalds@linux-foundation.org Subject: Re: [regression] 3.0-rc boot failure -- bisected to cd4ea6ae3982 Message-ID: <20110720201436.19e9689a@kryten> In-Reply-To: <1311070894.13765.180.camel@twins> References: <20110707102107.GA16666@in.ibm.com> <1310036375.3282.509.camel@twins> <20110714103418.7ef25b68@kryten> <20110714143521.5fe4fab6@kryten> <1310649379.2586.273.camel@twins> <20110715104547.29c3c509@kryten> <1311024956.2309.22.camel@laptop> <20110719144451.79bc69ab@kryten> <1311070894.13765.180.camel@twins> X-Mailer: Claws Mail 3.7.8 (GTK+ 2.24.4; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, > That looks very strange indeed.. up to node 23 there is the normal > symmetric matrix with all the trace elements on 10 (as we would expect > for local access), and some 4x4 sub-matrix stacked around the trace > with 20, suggesting a single hop distance, and the rest on 40 being > out-there. I retested with the latest version of numactl, and get correct results. I worked out why the patches don't boot, we weren't allocating any space for the cpumask and ran off the end of the allocation. Should we also use cpumask_copy instead of open coding it? I added that too. Anton Index: linux-2.6/kernel/sched.c =================================================================== --- linux-2.6.orig/kernel/sched.c 2011-07-20 01:54:08.191668781 -0500 +++ linux-2.6/kernel/sched.c 2011-07-20 04:45:36.203750525 -0500 @@ -7020,8 +7020,8 @@ if (cpumask_test_cpu(i, covered)) continue; - sg = kzalloc_node(sizeof(struct sched_group), GFP_KERNEL, - cpu_to_node(i)); + sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(), + GFP_KERNEL, cpu_to_node(i)); if (!sg) goto fail; @@ -7031,7 +7031,7 @@ child = *per_cpu_ptr(sdd->sd, i); if (child->child) { child = child->child; - *sg_span = *sched_domain_span(child); + cpumask_copy(sg_span, sched_domain_span(child)); } else cpumask_set_cpu(i, sg_span);