From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754733AbdJINyW (ORCPT ); Mon, 9 Oct 2017 09:54:22 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41920 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754246AbdJIMo6 (ORCPT ); Mon, 9 Oct 2017 08:44:58 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Ingo Molnar" , "Brian Gerst" , "Oleg Nesterov" , "Borislav Petkov" , "H. Peter Anvin" , "Paul Mackerras" , "Denys Vlasenko" , "Andy Lutomirski" , "Linus Torvalds" , "Anthony Liguori" , "Palik, Imre" , "Peter Zijlstra (Intel)" , "Arnaldo Carvalho de Melo" , "Thomas Gleixner" Date: Mon, 09 Oct 2017 13:44:25 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 167/192] perf/x86: Honor the architectural performance monitoring version In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.49-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "Palik, Imre" commit 2c33645d366d13b969d936b68b9f4875b1fdddea upstream. Architectural performance monitoring, version 1, doesn't support fixed counters. Currently, even if a hypervisor advertises support for architectural performance monitoring version 1, perf may still try to use the fixed counters, as the constraints are set up based on the CPU model. This patch ensures that perf honors the architectural performance monitoring version returned by CPUID, and it only uses the fixed counters for version 2 and above. (Some of the ideas in this patch came from Peter Zijlstra.) Signed-off-by: Imre Palik Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Andy Lutomirski Cc: Anthony Liguori Cc: Arnaldo Carvalho de Melo Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1433767609-1039-1-git-send-email-imrep.amz@gmail.com Signed-off-by: Ingo Molnar Signed-off-by: Ben Hutchings --- arch/x86/kernel/cpu/perf_event_intel.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -2642,13 +2642,13 @@ __init int intel_pmu_init(void) * counter, so do not extend mask to generic counters */ for_each_event_constraint(c, x86_pmu.event_constraints) { - if (c->cmask != FIXED_EVENT_FLAGS - || c->idxmsk64 == INTEL_PMC_MSK_FIXED_REF_CYCLES) { - continue; + if (c->cmask == FIXED_EVENT_FLAGS + && c->idxmsk64 != INTEL_PMC_MSK_FIXED_REF_CYCLES) { + c->idxmsk64 |= (1ULL << x86_pmu.num_counters) - 1; } - - c->idxmsk64 |= (1ULL << x86_pmu.num_counters) - 1; - c->weight += x86_pmu.num_counters; + c->idxmsk64 &= + ~(~0UL << (INTEL_PMC_IDX_FIXED + x86_pmu.num_counters_fixed)); + c->weight = hweight64(c->idxmsk64); } }