From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753135AbbC0Oiu (ORCPT ); Fri, 27 Mar 2015 10:38:50 -0400 Received: from mga02.intel.com ([134.134.136.20]:37104 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752709AbbC0Oir (ORCPT ); Fri, 27 Mar 2015 10:38:47 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,479,1422950400"; d="scan'208";a="698848589" From: kan.liang@intel.com To: a.p.zijlstra@chello.nl Cc: eranian@google.com, andi@firstfloor.org, linux-kernel@vger.kernel.org, Kan Liang Subject: [PATCH V2 1/1] perf/x86: filter branches for PEBS event Date: Fri, 27 Mar 2015 10:38:25 -0400 Message-Id: <1427467105-9260-1-git-send-email-kan.liang@intel.com> X-Mailer: git-send-email 1.8.3.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kan Liang For supporting Intel LBR branches filtering, Intel LBR sharing logic mechanism is introduced from commit b36817e88630 ("perf/x86: Add Intel LBR sharing logic"). It modifies __intel_shared_reg_get_constraints to config lbr_sel, which is finally used to set LBR_SELECT. However, the intel_shared_regs_constraints is called after intel_pebs_constraints. The PEBS event will return immediately after intel_pebs_constraints. So it's impossible to filter branches for PEBS event. This patch move intel_shared_regs_constraints ahead of intel_pebs_constraints. We can safely do that because the intel_shared_regs_constraints only returns emptyconstraint if its rejecting the event, otherwise it returns NULL such that we continue calling intel_pebs_constraints and x86_get_event_constraint. Signed-off-by: Kan Liang --- Changes since V1: - Move all shared regs ahead of intel_pebs_constraints - Modify the description and quote Peter's comments. arch/x86/kernel/cpu/perf_event_intel.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 9f1dd18..83bee99 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1635,11 +1635,11 @@ intel_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event if (c) return c; - c = intel_pebs_constraints(event); + c = intel_shared_regs_constraints(cpuc, event); if (c) return c; - c = intel_shared_regs_constraints(cpuc, event); + c = intel_pebs_constraints(event); if (c) return c; -- 1.8.3.1