From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756192AbaCZWKN (ORCPT ); Wed, 26 Mar 2014 18:10:13 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:58422 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751683AbaCZWKM (ORCPT ); Wed, 26 Mar 2014 18:10:12 -0400 Date: Wed, 26 Mar 2014 15:10:10 -0700 From: Andrew Morton To: Stephane Eranian Cc: Artem Fetishev , LKML , Ingo Molnar , Peter Zijlstra Subject: Re: [PATCH] x86: Fix boot on uniprocessor systems Message-Id: <20140326151010.777e0c527243c23da4a2b1f4@linux-foundation.org> In-Reply-To: References: <20140324225910.GB4937@owamsq.epam.com> <20140326133148.4a347bf956b1c5fd2ae40335@linux-foundation.org> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-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 On Wed, 26 Mar 2014 23:01:07 +0100 Stephane Eranian wrote: > On Wed, Mar 26, 2014 at 9:31 PM, Andrew Morton > wrote: > > On Tue, 25 Mar 2014 01:59:10 +0300 Artem Fetishev wrote: > > > >> On x86 uniprocessor systems topology_physical_package_id() returns -1 which > >> causes rapl_cpu_prepare() to leave rapl_pmu variable uninitialized which leads > >> to GPF in rapl_pmu_init(). See arch/x86/kernel/cpu/perf_event_intel_rapl.c. > >> > >> It turns out that physical_package_id and core_id can actually be retreived for > >> uniprocessor systems too. Enabling them also fixes rapl_pmu code. > >> > >> Signed-off-by: Artem Fetishev > >> --- > >> diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h > >> index d35f24e..1306d11 100644 > >> --- a/arch/x86/include/asm/topology.h > >> +++ b/arch/x86/include/asm/topology.h > >> @@ -119,9 +119,10 @@ static inline void setup_node_to_cpumask_map(void) { } > >> > >> extern const struct cpumask *cpu_coregroup_mask(int cpu); > >> > >> -#ifdef ENABLE_TOPO_DEFINES > >> #define topology_physical_package_id(cpu) (cpu_data(cpu).phys_proc_id) > >> #define topology_core_id(cpu) (cpu_data(cpu).cpu_core_id) > >> + > >> +#ifdef ENABLE_TOPO_DEFINES > >> #define topology_core_cpumask(cpu) (per_cpu(cpu_core_map, cpu)) > >> #define topology_thread_cpumask(cpu) (per_cpu(cpu_sibling_map, cpu)) > >> #endif > > > > The patch applies to 3.13 and perhaps earlier kernels. Is it needed in > > those kernel versions? > > Before 3.13 there was no RAPL support. > But it seems the patch is still useful regardless Is that an ack? If so I'll squirt it Linuswards right now for 3.14.