From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753336AbcD2Ess (ORCPT ); Fri, 29 Apr 2016 00:48:48 -0400 Received: from mail-pf0-f180.google.com ([209.85.192.180]:33790 "EHLO mail-pf0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753101AbcD2Eqn (ORCPT ); Fri, 29 Apr 2016 00:46:43 -0400 From: David Carrillo-Cisneros To: Peter Zijlstra , Alexander Shishkin , Arnaldo Carvalho de Melo , Ingo Molnar Cc: Vikas Shivappa , Matt Fleming , Tony Luck , Stephane Eranian , Paul Turner , David Carrillo-Cisneros , x86@kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 24/32] perf/x86/intel/cqm: use PERF_INACTIVE_*_READ_* flags in CQM Date: Thu, 28 Apr 2016 21:43:30 -0700 Message-Id: <1461905018-86355-25-git-send-email-davidcc@google.com> X-Mailer: git-send-email 2.8.0.rc3.226.g39d4020 In-Reply-To: <1461905018-86355-1-git-send-email-davidcc@google.com> References: <1461905018-86355-1-git-send-email-davidcc@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Use newly added pmu_event flags to: - Allow thread events to be read from any CPU even if not in ACTIVE state. Since inter-package values are polled, a thread's occupancy is always: local occupancy (read from hw) + remote occupancy (polled values) - Allow cpu/cgroup events to be read from any CPU in the package where they run. This potentially saves IPIs when the read function runs in the same package but in a distinct CPU than the event. Since reading will always return a new value and inherit_stats is not supported (due to all children events sharing the same RMID), there is no need to read during sched_out of an event. Reviewed-by: Stephane Eranian Signed-off-by: David Carrillo-Cisneros --- arch/x86/events/intel/cqm.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/events/intel/cqm.c b/arch/x86/events/intel/cqm.c index c14f1c7..daf9fdf 100644 --- a/arch/x86/events/intel/cqm.c +++ b/arch/x86/events/intel/cqm.c @@ -2702,6 +2702,16 @@ static int intel_cqm_event_init(struct perf_event *event) */ event->pmu_event_flags |= PERF_CGROUP_NO_RECURSION; + /* Events in CQM PMU are per-package and can be read even when + * the cpu is not running the event. + */ + if (event->cpu < 0) { + WARN_ON_ONCE(!(event->attach_state & PERF_ATTACH_TASK)); + event->pmu_event_flags |= PERF_INACTIVE_EV_READ_ANY_CPU; + } else { + event->pmu_event_flags |= PERF_INACTIVE_CPU_READ_PKG; + } + mutex_lock(&cqm_mutex); -- 2.8.0.rc3.226.g39d4020