From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752705AbbCZSsg (ORCPT ); Thu, 26 Mar 2015 14:48:36 -0400 Received: from mga02.intel.com ([134.134.136.20]:37575 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752095AbbCZSsf (ORCPT ); Thu, 26 Mar 2015 14:48:35 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.11,474,1422950400"; d="scan'208";a="698345879" 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 1/1] perf/x86: filter branches for PEBS event Date: Thu, 26 Mar 2015 14:13:23 -0400 Message-Id: <1427393603-3533-1-git-send-email-kan.liang@intel.com> X-Mailer: git-send-email 1.8.3.2 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 for branch_reg ahead of intel_pebs_constraints. intel_shared_regs_constraints for branch_reg doesn't modify event->hw, so it's safe to be called before intel_pebs_constraints. intel_shared_regs_constraints for branch_reg also special case when it returns &emptyconstraint. It put constraints for extra_reg. This patch remove it. Because it will never get constraints for extra_reg if return is &emptyconstraint. Signed-off-by: Kan Liang --- arch/x86/kernel/cpu/perf_event_intel.c | 34 ++++++++++++---------------------- 1 file changed, 12 insertions(+), 22 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 9f1dd18..247780a 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1587,25 +1587,14 @@ __intel_shared_reg_put_constraints(struct cpu_hw_events *cpuc, static struct event_constraint * intel_shared_regs_constraints(struct cpu_hw_events *cpuc, - struct perf_event *event) + struct perf_event *event, + struct hw_perf_event_extra *reg) { - struct event_constraint *c = NULL, *d; - struct hw_perf_event_extra *xreg, *breg; + struct event_constraint *c = NULL; + + if (reg->idx != EXTRA_REG_NONE) + c = __intel_shared_reg_get_constraints(cpuc, event, reg); - xreg = &event->hw.extra_reg; - if (xreg->idx != EXTRA_REG_NONE) { - c = __intel_shared_reg_get_constraints(cpuc, event, xreg); - if (c == &emptyconstraint) - return c; - } - breg = &event->hw.branch_reg; - if (breg->idx != EXTRA_REG_NONE) { - d = __intel_shared_reg_get_constraints(cpuc, event, breg); - if (d == &emptyconstraint) { - __intel_shared_reg_put_constraints(cpuc, xreg); - c = d; - } - } return c; } @@ -1629,17 +1618,18 @@ x86_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) static struct event_constraint * intel_get_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) { - struct event_constraint *c; + struct event_constraint *c, *d; c = intel_bts_constraints(event); if (c) return c; - c = intel_pebs_constraints(event); - if (c) - return c; + c = intel_shared_regs_constraints(cpuc, event, &event->hw.branch_reg); + d = intel_pebs_constraints(event); + if (d || c) + return (d) ? (d) : (c); - c = intel_shared_regs_constraints(cpuc, event); + c = intel_shared_regs_constraints(cpuc, event, &event->hw.extra_reg); if (c) return c; -- 1.8.3.2