Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764714AbZDHLc6 (ORCPT ); Wed, 8 Apr 2009 07:32:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1764439AbZDHLZ7 (ORCPT ); Wed, 8 Apr 2009 07:25:59 -0400 Received: from e28smtp05.in.ibm.com ([59.145.155.5]:51717 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1764438AbZDHLZ5 (ORCPT ); Wed, 8 Apr 2009 07:25:57 -0400 Message-ID: <49DC89A3.3090605@linux.vnet.ibm.com> Date: Wed, 08 Apr 2009 16:55:23 +0530 From: Mahesh Jagannath Salgaonkar User-Agent: Thunderbird 2.0.0.21 (X11/20090320) MIME-Version: 1.0 To: Linux Kernel , Suresh B Siddha , Ingo Molnar , Venkatesh Pallipadi CC: svaidy@linux.vnet.ibm.com, balbir@linux.vnet.ibm.com, dipankar@in.ibm.com, Peter Zijlstra Subject: [PATCH] Don't export sched_mc_power_savings on multi-socket single core system Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1785 Lines: 43 Fix to prevent sched_mc_power_saving from being exported through sysfs for multi-scoket single core system. Max cores should be always greater than one (1). My earlier patch that introduced fix for not exporting 'sched_mc_power_saving' on laptops broke it on multi-socket single core system. This fix addresses issue on both laptop and multi-socket single core system. Below are the Test results: 1. Single socket - multi-core Before Patch: Does not export 'sched_mc_power_saving' After Patch: Does not export 'sched_mc_power_saving' Result: Pass 2. Multi Socket - single core Before Patch: exports 'sched_mc_power_saving' After Patch: Does not export 'sched_mc_power_saving' Result: Pass 3. Multi Socket - Multi core Before Patch: exports 'sched_mc_power_saving' After Patch: exports 'sched_mc_power_saving' Signed-off-by: Mahesh Salgaonkar Index: linux-2.6/arch/x86/include/asm/topology.h =================================================================== --- linux-2.6.orig/arch/x86/include/asm/topology.h +++ linux-2.6/arch/x86/include/asm/topology.h @@ -203,7 +203,8 @@ struct pci_bus; void set_pci_bus_resources_arch_default(struct pci_bus *b); #ifdef CONFIG_SMP -#define mc_capable() (cpumask_weight(cpu_core_mask(0)) != nr_cpu_ids) +#define mc_capable() (boot_cpu_data.x86_max_cores > 1) && \ + (cpumask_weight(cpu_core_mask(0)) != nr_cpu_ids) #define smt_capable() (smp_num_siblings > 1) #endif -- 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/