From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751238AbdAQKNO (ORCPT ); Tue, 17 Jan 2017 05:13:14 -0500 Received: from terminus.zytor.com ([198.137.202.10]:46814 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751103AbdAQKNM (ORCPT ); Tue, 17 Jan 2017 05:13:12 -0500 Date: Tue, 17 Jan 2017 02:12:57 -0800 From: tip-bot for Zhou Chengming Message-ID: Cc: zhouchengming1@huawei.com, linux-kernel@vger.kernel.org, hpa@zytor.com, qiaonuohan@huawei.com, tglx@linutronix.de, mingo@kernel.org Reply-To: zhouchengming1@huawei.com, linux-kernel@vger.kernel.org, qiaonuohan@huawei.com, hpa@zytor.com, tglx@linutronix.de, mingo@kernel.org In-Reply-To: <1484536871-3131-1-git-send-email-zhouchengming1@huawei.com> References: <1484536871-3131-1-git-send-email-zhouchengming1@huawei.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/urgent] perf/x86/intel: Handle exclusive threadid correctly on CPU hotplug Git-Commit-ID: 4e71de7986386d5fd3765458f27d612931f27f5e 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 Commit-ID: 4e71de7986386d5fd3765458f27d612931f27f5e Gitweb: http://git.kernel.org/tip/4e71de7986386d5fd3765458f27d612931f27f5e Author: Zhou Chengming AuthorDate: Mon, 16 Jan 2017 11:21:11 +0800 Committer: Thomas Gleixner CommitDate: Tue, 17 Jan 2017 11:08:36 +0100 perf/x86/intel: Handle exclusive threadid correctly on CPU hotplug The CPU hotplug function intel_pmu_cpu_starting() sets cpu_hw_events.excl_thread_id unconditionally to 1 when the shared exclusive counters data structure is already availabe for the sibling thread. This works during the boot process because the first sibling gets threadid 0 assigned and the second sibling which shares the data structure gets 1. But when the first thread of the core is offlined and onlined again it shares the data structure with the second thread and gets exclusive thread id 1 assigned as well. Prevent this by checking the threadid of the already online thread. [ tglx: Rewrote changelog ] Signed-off-by: Zhou Chengming Cc: NuoHan Qiao Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: kan.liang@intel.com Cc: dave.hansen@linux.intel.com Cc: eranian@google.com Cc: qiaonuohan@huawei.com Cc: davidcc@google.com Cc: guohanjun@huawei.com Link: http://lkml.kernel.org/r/1484536871-3131-1-git-send-email-zhouchengming1@huawei.com Signed-off-by: Thomas Gleixner --- --- arch/x86/events/intel/core.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- arch/x86/events/intel/core.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index d611cab..eb1484c 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3176,13 +3176,16 @@ static void intel_pmu_cpu_starting(int cpu) if (x86_pmu.flags & PMU_FL_EXCL_CNTRS) { for_each_cpu(i, topology_sibling_cpumask(cpu)) { + struct cpu_hw_events *sibling; struct intel_excl_cntrs *c; - c = per_cpu(cpu_hw_events, i).excl_cntrs; + sibling = &per_cpu(cpu_hw_events, i); + c = sibling->excl_cntrs; if (c && c->core_id == core_id) { cpuc->kfree_on_online[1] = cpuc->excl_cntrs; cpuc->excl_cntrs = c; - cpuc->excl_thread_id = 1; + if (!sibling->excl_thread_id) + cpuc->excl_thread_id = 1; break; } }