Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753327AbaKEDKd (ORCPT ); Tue, 4 Nov 2014 22:10:33 -0500 Received: from mga11.intel.com ([192.55.52.93]:13763 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753235AbaKEDKW (ORCPT ); Tue, 4 Nov 2014 22:10:22 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,317,1413270000"; d="scan'208";a="617287004" From: Kan Liang To: a.p.zijlstra@chello.nl, eranian@google.com Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, paulus@samba.org, acme@kernel.org, jolsa@redhat.com, ak@linux.intel.com, Kan Liang Subject: [PATCH V7 10/17] perf, core: simplify need branch stack check Date: Tue, 4 Nov 2014 21:56:06 -0500 Message-Id: <1415156173-10035-11-git-send-email-kan.liang@intel.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1415156173-10035-1-git-send-email-kan.liang@intel.com> References: <1415156173-10035-1-git-send-email-kan.liang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yan, Zheng Using event->attr.branch_sample_type to replace intel_pmu_needs_lbr_smpl() for avoiding duplicating code that implicitly enables the LBR. Currently, branch stack can be enabled by user explicitly requested branch sampling or implicit branch sampling to correct PEBS skid. For user explicitly requested branch sampling, the branch_sample_type is explicitly set by user. For PEBS case, the branch_sample_type is also implicitly set to PERF_SAMPLE_BRANCH_ANY in x86_pmu_hw_config. Signed-off-by: Yan, Zheng Signed-off-by: Kan Liang --- arch/x86/kernel/cpu/perf_event_intel.c | 20 +++----------------- include/linux/perf_event.h | 5 +++++ kernel/events/core.c | 3 +++ 3 files changed, 11 insertions(+), 17 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index a0c0739..5f449fb 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1029,20 +1029,6 @@ static __initconst const u64 slm_hw_cache_event_ids }, }; -static inline bool intel_pmu_needs_lbr_smpl(struct perf_event *event) -{ - /* user explicitly requested branch sampling */ - if (has_branch_stack(event)) - return true; - - /* implicit branch sampling to correct PEBS skid */ - if (x86_pmu.intel_cap.pebs_trap && event->attr.precise_ip > 1 && - x86_pmu.intel_cap.pebs_format < 2) - return true; - - return false; -} - static void intel_pmu_disable_all(void) { struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); @@ -1207,7 +1193,7 @@ static void intel_pmu_disable_event(struct perf_event *event) * must disable before any actual event * because any event may be combined with LBR */ - if (intel_pmu_needs_lbr_smpl(event)) + if (needs_branch_stack(event)) intel_pmu_lbr_disable(event); if (unlikely(hwc->config_base == MSR_ARCH_PERFMON_FIXED_CTR_CTRL)) { @@ -1268,7 +1254,7 @@ static void intel_pmu_enable_event(struct perf_event *event) * must enabled before any actual event * because any event may be combined with LBR */ - if (intel_pmu_needs_lbr_smpl(event)) + if (needs_branch_stack(event)) intel_pmu_lbr_enable(event); if (event->attr.exclude_host) @@ -1747,7 +1733,7 @@ static int intel_pmu_hw_config(struct perf_event *event) if (event->attr.precise_ip && x86_pmu.pebs_aliases) x86_pmu.pebs_aliases(event); - if (intel_pmu_needs_lbr_smpl(event)) { + if (needs_branch_stack(event)) { ret = intel_pmu_setup_lbr_filter(event); if (ret) return ret; diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 84ec3e6..0d67460 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -796,6 +796,11 @@ static inline bool has_branch_stack(struct perf_event *event) return event->attr.sample_type & PERF_SAMPLE_BRANCH_STACK; } +static inline bool needs_branch_stack(struct perf_event *event) +{ + return event->attr.branch_sample_type != 0; +} + extern int perf_output_begin(struct perf_output_handle *handle, struct perf_event *event, unsigned int size); extern void perf_output_end(struct perf_output_handle *handle); diff --git a/kernel/events/core.c b/kernel/events/core.c index 4360c95..3f3e43d 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -7015,6 +7015,9 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu, if (attr->inherit && (attr->read_format & PERF_FORMAT_GROUP)) goto err_ns; + if (!has_branch_stack(event)) + event->attr.branch_sample_type = 0; + pmu = perf_init_event(event); if (!pmu) goto err_ns; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/