| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "inplace_sampler_lib.h" |
| |
| #include <inttypes.h> |
| #include <pthread.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/syscall.h> |
| #include <sys/ucontext.h> |
| #include <unistd.h> |
| |
| #include <map> |
| #include <memory> |
| #include <queue> |
| #include <set> |
| #include <string> |
| #include <unordered_map> |
| |
| #include <android-base/logging.h> |
| #include <android-base/macros.h> |
| #include <backtrace/Backtrace.h> |
| #define LOG_TAG "InplaceSampler" |
| #include <log/log.h> |
| |
| #include "environment.h" |
| #include "UnixSocket.h" |
| #include "utils.h" |
| |
| #define DEFAULT_SIGNO SIGRTMAX |
| static constexpr int DEFAULT_SAMPLE_FREQ = 4000; |
| static constexpr int CHECK_THREADS_INTERVAL_IN_MS = 200; |
| |
| namespace { |
| |
| struct ThreadInfo { |
| std::string name; |
| }; |
| |
| // SampleManager controls the whole sampling process: |
| // Read commands from simpleperf |
| // Set up timers to send signals for each profiled thread regularly. |
| // Send thread info and map info to simpleperf. |
| class SampleManager { |
| public: |
| SampleManager(std::unique_ptr<UnixSocketConnection> conn) : conn_(std::move(conn)), |
| tid_(gettid()), signo_(DEFAULT_SIGNO), sample_freq_(DEFAULT_SAMPLE_FREQ), |
| sample_period_in_ns_(0), dump_callchain_(false), monitor_all_threads_(true) { |
| } |
| void Run(); |
| |
| private: |
| bool HandleMessage(const UnixSocketMessage& msg); |
| bool ParseStartProfilingMessage(const UnixSocketMessage& msg); |
| bool SendStartProfilingReplyMessage(bool ok); |
| bool StartProfiling(); |
| bool InstallSignalHandler(); |
| bool CheckThreads(); |
| bool CheckThreadNameChange(uint64_t timestamp); |
| bool CheckMapChange(uint64_t timestamp); |
| void SendThreadMapInfo(); |
| void SendFakeSampleRecord(); |
| |
| std::unique_ptr<UnixSocketConnection> conn_; |
| |
| int tid_; |
| int signo_; |
| uint32_t sample_freq_; |
| uint32_t sample_period_in_ns_; |
| bool dump_callchain_; |
| bool monitor_all_threads_; |
| std::set<int> monitor_tid_filter_; |
| std::map<int, ThreadInfo> threads_; |
| std::map<uint64_t, ThreadMmap> maps_; |
| std::queue<std::unique_ptr<char[]>> thread_map_info_q_; |
| |
| IOEventLoop loop_; |
| }; |
| |
| void SampleManager::Run() { |
| auto read_callback = [&](const UnixSocketMessage& msg) { |
| return HandleMessage(msg); |
| }; |
| auto close_callback = [&]() { |
| return loop_.ExitLoop(); |
| }; |
| if (!conn_->PrepareForIO(loop_, read_callback, close_callback)) { |
| return; |
| } |
| loop_.RunLoop(); |
| } |
| |
| bool SampleManager::HandleMessage(const UnixSocketMessage& msg) { |
| if (msg.type == START_PROFILING) { |
| if (!ParseStartProfilingMessage(msg)) { |
| if (!SendStartProfilingReplyMessage(false)) { |
| return false; |
| } |
| return conn_->NoMoreMessage(); |
| } |
| if (!SendStartProfilingReplyMessage(true)) { |
| return false; |
| } |
| return StartProfiling(); |
| } |
| if (msg.type == END_PROFILING) { |
| // Close connection after clearing send buffer. |
| return conn_->NoMoreMessage(); |
| } |
| LOG(ERROR) << "Unexpected msg type: " << msg.type; |
| return false; |
| } |
| |
| bool SampleManager::ParseStartProfilingMessage(const UnixSocketMessage& msg) { |
| char* option = const_cast<char*>(msg.data); |
| while (option != nullptr && *option != '\0') { |
| char* next_option = strchr(option, ' '); |
| if (next_option != nullptr) { |
| *next_option++ = '\0'; |
| } |
| char* equal_op = strchr(option, '='); |
| if (equal_op != nullptr) { |
| char* key = option; |
| *equal_op = '\0'; |
| char* value = equal_op + 1; |
| if (strcmp(key, "freq") == 0) { |
| sample_freq_ = atoi(value); |
| } else if (strcmp(key, "signal") == 0) { |
| signo_ = atoi(value); |
| } else if (strcmp(key, "tids") == 0) { |
| monitor_all_threads_ = false; |
| while (*value != '\0') { |
| int tid = static_cast<int>(strtol(value, &value, 10)); |
| monitor_tid_filter_.insert(tid); |
| if (*value == ',') { |
| ++value; |
| } |
| } |
| } else if (strcmp(key, "dump_callchain") == 0) { |
| dump_callchain_ = (strcmp(value, "1") == 0); |
| } |
| } |
| option = next_option; |
| } |
| if (sample_freq_ == 0 || sample_freq_ > 1000000000) { |
| LOG(ERROR) << "Unexpected sample_freq: " << sample_freq_; |
| return false; |
| } |
| if (sample_freq_ == 1) { |
| sample_period_in_ns_ = 999999999; |
| } else { |
| sample_period_in_ns_ = 1000000000 / sample_freq_; |
| } |
| return true; |
| } |
| |
| bool SampleManager::SendStartProfilingReplyMessage(bool ok) { |
| const char* s = ok ? "ok" : "error"; |
| size_t size = sizeof(UnixSocketMessage) + strlen(s) + 1; |
| std::unique_ptr<char[]> data(new char[size]); |
| UnixSocketMessage* msg = reinterpret_cast<UnixSocketMessage*>(data.get()); |
| msg->len = size; |
| msg->type = START_PROFILING_REPLY; |
| strcpy(msg->data, s); |
| return conn_->SendMessage(*msg, true); |
| } |
| |
| bool SampleManager::StartProfiling() { |
| if (!InstallSignalHandler()) { |
| return false; |
| } |
| if (!CheckThreads()) { |
| return false; |
| } |
| timeval tv; |
| tv.tv_sec = CHECK_THREADS_INTERVAL_IN_MS / 1000; |
| tv.tv_usec = CHECK_THREADS_INTERVAL_IN_MS % 1000 * 1000; |
| return loop_.AddPeriodicEvent(tv, [&]() { |
| return CheckThreads(); |
| }); |
| } |
| |
| bool SampleManager::InstallSignalHandler() { |
| return true; |
| } |
| |
| bool SampleManager::CheckThreads() { |
| uint64_t timestamp = GetSystemClock(); |
| if (!CheckMapChange(timestamp)) { |
| return false; |
| } |
| if (!CheckThreadNameChange(timestamp)) { |
| return false; |
| } |
| SendThreadMapInfo(); |
| // For testing. |
| SendFakeSampleRecord(); |
| return true; |
| } |
| |
| bool SampleManager::CheckThreadNameChange(uint64_t timestamp) { |
| std::vector<pid_t> tids = GetThreadsInProcess(getpid()); |
| std::map<pid_t, std::string> current; |
| for (auto& tid : tids) { |
| if (tid == tid_) { |
| // Skip sample thread. |
| continue; |
| } |
| if (monitor_all_threads_ || monitor_tid_filter_.find(tid) != monitor_tid_filter_.end()) { |
| std::string name; |
| if (GetThreadName(tid, &name)) { |
| current[tid] = name; |
| } |
| } |
| } |
| // Check new threads or threads with new names. |
| for (auto& pair : current) { |
| pid_t tid = pair.first; |
| auto it = threads_.find(tid); |
| if (it == threads_.end() || it->second.name != pair.second) { |
| threads_[tid].name = pair.second; |
| size_t size = sizeof(UnixSocketMessage) + sizeof(uint64_t) + sizeof(uint32_t) + |
| pair.second.size() + 1; |
| std::unique_ptr<char[]> data(new char[size]); |
| UnixSocketMessage* msg = reinterpret_cast<UnixSocketMessage*>(data.get()); |
| msg->len = size; |
| msg->type = THREAD_INFO; |
| char* p = msg->data; |
| MoveToBinaryFormat(timestamp, p); |
| MoveToBinaryFormat(static_cast<uint32_t>(tid), p); |
| MoveToBinaryFormat(pair.second.c_str(), pair.second.size() + 1, p); |
| thread_map_info_q_.push(std::move(data)); |
| } |
| } |
| // Check deleted threads. |
| for (auto it = threads_.begin(); it != threads_.end();) { |
| int tid = it->first; |
| if (current.find(tid) == current.end()) { |
| it = threads_.erase(it); |
| } else { |
| ++it; |
| } |
| } |
| return true; |
| } |
| |
| bool SampleManager::CheckMapChange(uint64_t timestamp) { |
| std::vector<ThreadMmap> maps; |
| if (!GetThreadMmapsInProcess(getpid(), &maps)) { |
| return false; |
| } |
| // Check new maps or changed maps. |
| for (auto& map : maps) { |
| if (!map.executable) { |
| continue; |
| } |
| auto it = maps_.find(map.start_addr); |
| if (it == maps_.end() || it->second.len != map.len || it->second.pgoff != map.pgoff || |
| it->second.name != map.name) { |
| maps_[map.start_addr] = map; |
| size_t size = sizeof(UnixSocketMessage) + sizeof(uint64_t) * 4 + map.name.size() + 1; |
| std::unique_ptr<char[]> data(new char[size]); |
| UnixSocketMessage* msg = reinterpret_cast<UnixSocketMessage*>(data.get()); |
| msg->len = size; |
| msg->type = MAP_INFO; |
| char* p = msg->data; |
| MoveToBinaryFormat(timestamp, p); |
| MoveToBinaryFormat(map.start_addr, p); |
| MoveToBinaryFormat(map.len, p); |
| MoveToBinaryFormat(map.pgoff, p); |
| MoveToBinaryFormat(map.name.c_str(), map.name.size() + 1, p); |
| thread_map_info_q_.push(std::move(data)); |
| } |
| } |
| return true; |
| } |
| |
| void SampleManager::SendThreadMapInfo() { |
| while (!thread_map_info_q_.empty()) { |
| auto& data = thread_map_info_q_.front(); |
| UnixSocketMessage* msg = reinterpret_cast<UnixSocketMessage*>(data.get()); |
| if (!conn_->SendMessage(*msg, false)) { |
| break; |
| } |
| thread_map_info_q_.pop(); |
| } |
| } |
| |
| static void FakeFunction() { |
| } |
| |
| void SampleManager::SendFakeSampleRecord() { |
| size_t size = sizeof(UnixSocketMessage) + sizeof(uint64_t) * 2 + sizeof(uint32_t) * 3; |
| std::unique_ptr<char[]> data(new char[size]); |
| UnixSocketMessage* msg = reinterpret_cast<UnixSocketMessage*>(data.get()); |
| uint64_t ip = static_cast<uint64_t>(reinterpret_cast<uintptr_t>(&FakeFunction)); |
| msg->len = size; |
| msg->type = SAMPLE_INFO; |
| char* p = msg->data; |
| MoveToBinaryFormat(GetSystemClock(), p); |
| MoveToBinaryFormat(static_cast<uint32_t>(tid_), p); |
| MoveToBinaryFormat(1u, p); |
| MoveToBinaryFormat(1u, p); |
| MoveToBinaryFormat(ip, p); |
| conn_->SendMessage(*msg, false); |
| } |
| |
| static void* CommunicationThread(void*) { |
| pthread_setname_np(pthread_self(), "inplace_sampler"); |
| std::string server_path = "inplace_sampler_server_" + std::to_string(getpid()); |
| std::unique_ptr<UnixSocketServer> server = UnixSocketServer::Create(server_path, true); |
| if (server == nullptr) { |
| LOG(ERROR) << "failed to create server at path " << server_path; |
| return nullptr; |
| } |
| LOG(INFO) << "Create inplace_sampler_server at " << server_path; |
| while (true) { |
| std::unique_ptr<UnixSocketConnection> conn = server->AcceptConnection(); |
| if (conn == nullptr) { |
| break; |
| } |
| SampleManager manager(std::move(conn)); |
| manager.Run(); |
| } |
| return nullptr; |
| } |
| |
| __attribute__((constructor)) void InitSampler() { |
| pthread_attr_t attr; |
| if (pthread_attr_init(&attr) != 0) { |
| LOG(ERROR) << "pthread_attr_init failed"; |
| return; |
| } |
| if (pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0) { |
| LOG(ERROR) << "pthread_attr_setdetachstate failed"; |
| return; |
| } |
| pthread_t thread; |
| if (pthread_create(&thread, &attr, CommunicationThread, nullptr) != 0) { |
| LOG(ERROR) << "pthread_create failed"; |
| return; |
| } |
| pthread_attr_destroy(&attr); |
| } |
| |
| } // namespace |