1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SRC_PROFILING_PERF_EVENT_CONFIG_H_ 18 #define SRC_PROFILING_PERF_EVENT_CONFIG_H_ 19 20 #include <string> 21 22 #include <linux/perf_event.h> 23 #include <stdint.h> 24 #include <sys/types.h> 25 26 #include "perfetto/base/flat_set.h" 27 #include "perfetto/ext/base/optional.h" 28 #include "perfetto/tracing/core/data_source_config.h" 29 30 #include "protos/perfetto/config/profiling/perf_event_config.pbzero.h" 31 32 namespace perfetto { 33 namespace profiling { 34 35 // Parsed whitelist/blacklist for filtering samples. 36 // An empty whitelist set means that all targets are allowed. 37 struct TargetFilter { 38 base::FlatSet<std::string> cmdlines; 39 base::FlatSet<std::string> exclude_cmdlines; 40 base::FlatSet<pid_t> pids; 41 base::FlatSet<pid_t> exclude_pids; 42 }; 43 44 // Describes a single profiling configuration. Bridges the gap between the data 45 // source config proto, and the raw "perf_event_attr" structs to pass to the 46 // perf_event_open syscall. 47 class EventConfig { 48 public: 49 static base::Optional<EventConfig> Create(const DataSourceConfig& ds_config); 50 target_all_cpus()51 uint32_t target_all_cpus() const { return target_all_cpus_; } ring_buffer_pages()52 uint32_t ring_buffer_pages() const { return ring_buffer_pages_; } read_tick_period_ms()53 uint32_t read_tick_period_ms() const { return read_tick_period_ms_; } samples_per_tick_limit()54 uint32_t samples_per_tick_limit() const { return samples_per_tick_limit_; } remote_descriptor_timeout_ms()55 uint32_t remote_descriptor_timeout_ms() const { 56 return remote_descriptor_timeout_ms_; 57 } unwind_state_clear_period_ms()58 uint32_t unwind_state_clear_period_ms() const { 59 return unwind_state_clear_period_ms_; 60 } 61 filter()62 const TargetFilter& filter() const { return target_filter_; } 63 perf_attr()64 perf_event_attr* perf_attr() const { 65 return const_cast<perf_event_attr*>(&perf_event_attr_); 66 } 67 68 private: 69 EventConfig(const protos::pbzero::PerfEventConfig::Decoder& cfg, 70 uint32_t sampling_frequency, 71 uint32_t ring_buffer_pages, 72 uint32_t read_tick_period_ms, 73 uint32_t samples_per_tick_limit, 74 uint32_t remote_descriptor_timeout_ms, 75 TargetFilter target_filter); 76 77 // If true, process all system-wide samples. 78 const bool target_all_cpus_; 79 80 // Size (in 4k pages) of each per-cpu ring buffer shared with the kernel. 81 // Must be a power of two. 82 const uint32_t ring_buffer_pages_; 83 84 // Parameter struct for |perf_event_open| calls. 85 struct perf_event_attr perf_event_attr_ = {}; 86 87 // How often the ring buffers should be read. 88 const uint32_t read_tick_period_ms_; 89 90 // Guardrail for the amount of samples a given read attempt will extract from 91 // *each* per-cpu buffer. 92 const uint32_t samples_per_tick_limit_; 93 94 // Parsed whitelist/blacklist for filtering samples. 95 const TargetFilter target_filter_; 96 97 // Timeout for proc-fd lookup. 98 const uint32_t remote_descriptor_timeout_ms_; 99 100 // Optional period for clearing cached unwinder state. Skipped if zero. 101 const uint32_t unwind_state_clear_period_ms_; 102 }; 103 104 } // namespace profiling 105 } // namespace perfetto 106 107 #endif // SRC_PROFILING_PERF_EVENT_CONFIG_H_ 108