Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933240AbbLRVeo (ORCPT ); Fri, 18 Dec 2015 16:34:44 -0500 Received: from terminus.zytor.com ([198.137.202.10]:59072 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965324AbbLRVeT (ORCPT ); Fri, 18 Dec 2015 16:34:19 -0500 Date: Fri, 18 Dec 2015 13:34:09 -0800 From: tip-bot for Fenghua Yu Message-ID: Cc: hpa@zytor.com, vikas.shivappa@linux.intel.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, mingo@kernel.org, fenghua.yu@intel.com Reply-To: fenghua.yu@intel.com, linux-kernel@vger.kernel.org, mingo@kernel.org, tglx@linutronix.de, vikas.shivappa@linux.intel.com, hpa@zytor.com In-Reply-To: <1450392376-6397-3-git-send-email-fenghua.yu@intel.com> References: <1450392376-6397-3-git-send-email-fenghua.yu@intel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:x86/cache] x86/intel_rapl: Modify hot cpu notification handling Git-Commit-ID: 2a7a6718afed6b61628ca1845dc49827759bed7d X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3271 Lines: 93 Commit-ID: 2a7a6718afed6b61628ca1845dc49827759bed7d Gitweb: http://git.kernel.org/tip/2a7a6718afed6b61628ca1845dc49827759bed7d Author: Fenghua Yu AuthorDate: Thu, 17 Dec 2015 14:46:07 -0800 Committer: H. Peter Anvin CommitDate: Fri, 18 Dec 2015 13:17:55 -0800 x86/intel_rapl: Modify hot cpu notification handling From: Vikas Shivappa - In rapl_cpu_init, use the existing package<->core map instead of looping through all cpus in rapl_cpumask. - In rapl_cpu_exit, use the same mapping instead of looping all online cpus. In large systems with large number of cpus the time taken to loop may be expensive and also the time increase linearly. Signed-off-by: Vikas Shivappa Link: http://lkml.kernel.org/r/1450392376-6397-3-git-send-email-fenghua.yu@intel.com Signed-off-by: Fenghua Yu --- arch/x86/kernel/cpu/perf_event_intel_rapl.c | 35 ++++++++++++++--------------- 1 file changed, 17 insertions(+), 18 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel_rapl.c b/arch/x86/kernel/cpu/perf_event_intel_rapl.c index ed446bd..0e0fe70 100644 --- a/arch/x86/kernel/cpu/perf_event_intel_rapl.c +++ b/arch/x86/kernel/cpu/perf_event_intel_rapl.c @@ -130,6 +130,12 @@ static struct pmu rapl_pmu_class; static cpumask_t rapl_cpu_mask; static int rapl_cntr_mask; +/* + * Temporary cpumask used during hot cpu notificaiton handling. The usage + * is serialized by hot cpu locks. + */ +static cpumask_t tmp_cpumask; + static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu); static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu_to_free); @@ -533,18 +539,16 @@ static struct pmu rapl_pmu_class = { static void rapl_cpu_exit(int cpu) { struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu); - int i, phys_id = topology_physical_package_id(cpu); int target = -1; + int i; /* find a new cpu on same package */ - for_each_online_cpu(i) { - if (i == cpu) - continue; - if (phys_id == topology_physical_package_id(i)) { - target = i; - break; - } - } + cpumask_and(&tmp_cpumask, topology_core_cpumask(cpu), cpu_online_mask); + cpumask_clear_cpu(cpu, &tmp_cpumask); + i = cpumask_any(&tmp_cpumask); + if (i < nr_cpu_ids) + target = i; + /* * clear cpu from cpumask * if was set in cpumask and still some cpu on package, @@ -566,15 +570,10 @@ static void rapl_cpu_exit(int cpu) static void rapl_cpu_init(int cpu) { - int i, phys_id = topology_physical_package_id(cpu); - - /* check if phys_is is already covered */ - for_each_cpu(i, &rapl_cpu_mask) { - if (phys_id == topology_physical_package_id(i)) - return; - } - /* was not found, so add it */ - cpumask_set_cpu(cpu, &rapl_cpu_mask); + /* check if cpu's package is already covered.If not, add it.*/ + cpumask_and(&tmp_cpumask, &rapl_cpu_mask, topology_core_cpumask(cpu)); + if (cpumask_empty(&tmp_cpumask)) + cpumask_set_cpu(cpu, &rapl_cpu_mask); } static __init void rapl_hsw_server_quirk(void) -- 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/