Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751947AbaACFtm (ORCPT ); Fri, 3 Jan 2014 00:49:42 -0500 Received: from mga01.intel.com ([192.55.52.88]:23246 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751499AbaACFse (ORCPT ); Fri, 3 Jan 2014 00:48:34 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.95,595,1384329600"; d="scan'208";a="459449385" From: "Yan, Zheng" To: linux-kernel@vger.kernel.org Cc: a.p.zijlstra@chello.nl, mingo@kernel.org, acme@infradead.org, eranian@google.com, andi@firstfloor.org, "Yan, Zheng" Subject: [PATCH 10/14] perf, core: simplify need branch stack check Date: Fri, 3 Jan 2014 13:48:07 +0800 Message-Id: <1388728091-18564-11-git-send-email-zheng.z.yan@intel.com> X-Mailer: git-send-email 1.8.4.2 In-Reply-To: <1388728091-18564-1-git-send-email-zheng.z.yan@intel.com> References: <1388728091-18564-1-git-send-email-zheng.z.yan@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4827 Lines: 138 event->attr.branch_sample_type is non-zero no matter branch stack is enabled explicitly or is enabled implicitly. So we can use it toreplace intel_pmu_needs_lbr_smpl(). This avoids duplicating code that implicitly enables the LBR. Signed-off-by: Yan, Zheng --- arch/x86/kernel/cpu/perf_event_intel.c | 20 +++----------------- include/linux/perf_event.h | 5 +++++ kernel/events/core.c | 11 +++++++---- 3 files changed, 15 insertions(+), 21 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c index 84a1c09..722171c 100644 --- a/arch/x86/kernel/cpu/perf_event_intel.c +++ b/arch/x86/kernel/cpu/perf_event_intel.c @@ -1030,20 +1030,6 @@ 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 = &__get_cpu_var(cpu_hw_events); @@ -1208,7 +1194,7 @@ 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)) { @@ -1269,7 +1255,7 @@ 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) @@ -1741,7 +1727,7 @@ 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 147f9d3..0d88eb8 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -766,6 +766,11 @@ 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 d6d8dea..7dd4d58 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1138,7 +1138,7 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx) if (is_cgroup_event(event)) ctx->nr_cgroups++; - if (has_branch_stack(event)) + if (needs_branch_stack(event)) ctx->nr_branch_stack++; list_add_rcu(&event->event_entry, &ctx->event_list); @@ -1303,7 +1303,7 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx) cpuctx->cgrp = NULL; } - if (has_branch_stack(event)) + if (needs_branch_stack(event)) ctx->nr_branch_stack--; ctx->nr_events--; @@ -3202,7 +3202,7 @@ static void unaccount_event(struct perf_event *event) atomic_dec(&nr_freq_events); if (is_cgroup_event(event)) static_key_slow_dec_deferred(&perf_sched_events); - if (has_branch_stack(event)) + if (needs_branch_stack(event)) static_key_slow_dec_deferred(&perf_sched_events); unaccount_event_cpu(event, event->cpu); @@ -6627,7 +6627,7 @@ static void account_event(struct perf_event *event) if (atomic_inc_return(&nr_freq_events) == 1) tick_nohz_full_kick_all(); } - if (has_branch_stack(event)) + if (needs_branch_stack(event)) static_key_slow_inc(&perf_sched_events.key); if (is_cgroup_event(event)) static_key_slow_inc(&perf_sched_events.key); @@ -6735,6 +6735,9 @@ 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; -- 1.8.4.2 -- 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/