| /* |
| * Copyright (C) 2019 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. |
| */ |
| |
| #define LOG_TAG "perfetto_hprof" |
| |
| #include "perfetto_hprof.h" |
| |
| #include <android-base/logging.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <sched.h> |
| #include <signal.h> |
| #include <stdlib.h> |
| #include <sys/socket.h> |
| #include <sys/stat.h> |
| #include <sys/types.h> |
| #include <sys/un.h> |
| #include <sys/wait.h> |
| #include <thread> |
| #include <time.h> |
| |
| #include <limits> |
| #include <optional> |
| #include <type_traits> |
| |
| #include "gc/heap-visit-objects-inl.h" |
| #include "gc/heap.h" |
| #include "gc/scoped_gc_critical_section.h" |
| #include "mirror/object-refvisitor-inl.h" |
| #include "nativehelper/scoped_local_ref.h" |
| #include "perfetto/profiling/parse_smaps.h" |
| #include "perfetto/trace/interned_data/interned_data.pbzero.h" |
| #include "perfetto/trace/profiling/heap_graph.pbzero.h" |
| #include "perfetto/trace/profiling/profile_common.pbzero.h" |
| #include "perfetto/trace/profiling/smaps.pbzero.h" |
| #include "perfetto/config/profiling/java_hprof_config.pbzero.h" |
| #include "perfetto/protozero/packed_repeated_fields.h" |
| #include "perfetto/tracing.h" |
| #include "runtime-inl.h" |
| #include "runtime_callbacks.h" |
| #include "scoped_thread_state_change-inl.h" |
| #include "thread_list.h" |
| #include "well_known_classes.h" |
| #include "dex/descriptors_names.h" |
| |
| // There are three threads involved in this: |
| // * listener thread: this is idle in the background when this plugin gets loaded, and waits |
| // for data on on g_signal_pipe_fds. |
| // * signal thread: an arbitrary thread that handles the signal and writes data to |
| // g_signal_pipe_fds. |
| // * perfetto producer thread: once the signal is received, the app forks. In the newly forked |
| // child, the Perfetto Client API spawns a thread to communicate with traced. |
| |
| namespace perfetto_hprof { |
| |
| constexpr int kJavaHeapprofdSignal = __SIGRTMIN + 6; |
| constexpr time_t kWatchdogTimeoutSec = 120; |
| // This needs to be lower than the maximum acceptable chunk size, because this |
| // is checked *before* writing another submessage. We conservatively assume |
| // submessages can be up to 100k here for a 500k chunk size. |
| // DropBox has a 500k chunk limit, and each chunk needs to parse as a proto. |
| constexpr uint32_t kPacketSizeThreshold = 400000; |
| constexpr char kByte[1] = {'x'}; |
| static art::Mutex& GetStateMutex() { |
| static art::Mutex state_mutex("perfetto_hprof_state_mutex", art::LockLevel::kGenericBottomLock); |
| return state_mutex; |
| } |
| |
| static art::ConditionVariable& GetStateCV() { |
| static art::ConditionVariable state_cv("perfetto_hprof_state_cv", GetStateMutex()); |
| return state_cv; |
| } |
| |
| static int requested_tracing_session_id = 0; |
| static State g_state = State::kUninitialized; |
| |
| // Pipe to signal from the signal handler into a worker thread that handles the |
| // dump requests. |
| int g_signal_pipe_fds[2]; |
| static struct sigaction g_orig_act = {}; |
| |
| template <typename T> |
| uint64_t FindOrAppend(std::map<T, uint64_t>* m, const T& s) { |
| auto it = m->find(s); |
| if (it == m->end()) { |
| std::tie(it, std::ignore) = m->emplace(s, m->size()); |
| } |
| return it->second; |
| } |
| |
| void ArmWatchdogOrDie() { |
| timer_t timerid{}; |
| struct sigevent sev {}; |
| sev.sigev_notify = SIGEV_SIGNAL; |
| sev.sigev_signo = SIGKILL; |
| |
| if (timer_create(CLOCK_MONOTONIC, &sev, &timerid) == -1) { |
| // This only gets called in the child, so we can fatal without impacting |
| // the app. |
| PLOG(FATAL) << "failed to create watchdog timer"; |
| } |
| |
| struct itimerspec its {}; |
| its.it_value.tv_sec = kWatchdogTimeoutSec; |
| |
| if (timer_settime(timerid, 0, &its, nullptr) == -1) { |
| // This only gets called in the child, so we can fatal without impacting |
| // the app. |
| PLOG(FATAL) << "failed to arm watchdog timer"; |
| } |
| } |
| |
| bool StartsWith(const std::string& str, const std::string& prefix) { |
| return str.compare(0, prefix.length(), prefix) == 0; |
| } |
| |
| // Sample entries that match one of the following |
| // start with /system/ |
| // start with /vendor/ |
| // start with /data/app/ |
| // contains "extracted in memory from Y", where Y matches any of the above |
| bool ShouldSampleSmapsEntry(const perfetto::profiling::SmapsEntry& e) { |
| if (StartsWith(e.pathname, "/system/") || StartsWith(e.pathname, "/vendor/") || |
| StartsWith(e.pathname, "/data/app/")) { |
| return true; |
| } |
| if (StartsWith(e.pathname, "[anon:")) { |
| if (e.pathname.find("extracted in memory from /system/") != std::string::npos) { |
| return true; |
| } |
| if (e.pathname.find("extracted in memory from /vendor/") != std::string::npos) { |
| return true; |
| } |
| if (e.pathname.find("extracted in memory from /data/app/") != std::string::npos) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| class JavaHprofDataSource : public perfetto::DataSource<JavaHprofDataSource> { |
| public: |
| constexpr static perfetto::BufferExhaustedPolicy kBufferExhaustedPolicy = |
| perfetto::BufferExhaustedPolicy::kStall; |
| void OnSetup(const SetupArgs& args) override { |
| uint64_t normalized_cfg_tracing_session_id = |
| args.config->tracing_session_id() % std::numeric_limits<int32_t>::max(); |
| if (requested_tracing_session_id < 0) { |
| LOG(ERROR) << "invalid requested tracing session id " << requested_tracing_session_id; |
| return; |
| } |
| if (static_cast<uint64_t>(requested_tracing_session_id) != normalized_cfg_tracing_session_id) { |
| return; |
| } |
| |
| // This is on the heap as it triggers -Wframe-larger-than. |
| std::unique_ptr<perfetto::protos::pbzero::JavaHprofConfig::Decoder> cfg( |
| new perfetto::protos::pbzero::JavaHprofConfig::Decoder( |
| args.config->java_hprof_config_raw())); |
| |
| dump_smaps_ = cfg->dump_smaps(); |
| for (auto it = cfg->ignored_types(); it; ++it) { |
| std::string name = (*it).ToStdString(); |
| ignored_types_.emplace_back(std::move(name)); |
| } |
| // This tracing session ID matches the requesting tracing session ID, so we know heapprofd |
| // has verified it targets this process. |
| enabled_ = true; |
| } |
| |
| bool dump_smaps() { return dump_smaps_; } |
| bool enabled() { return enabled_; } |
| |
| void OnStart(const StartArgs&) override { |
| if (!enabled()) { |
| return; |
| } |
| art::MutexLock lk(art_thread(), GetStateMutex()); |
| if (g_state == State::kWaitForStart) { |
| g_state = State::kStart; |
| GetStateCV().Broadcast(art_thread()); |
| } |
| } |
| |
| // This datasource can be used with a trace config with a short duration_ms |
| // but a long datasource_stop_timeout_ms. In that case, OnStop is called (in |
| // general) before the dump is done. In that case, we handle the stop |
| // asynchronously, and notify the tracing service once we are done. |
| // In case OnStop is called after the dump is done (but before the process) |
| // has exited, we just acknowledge the request. |
| void OnStop(const StopArgs& a) override { |
| art::MutexLock lk(art_thread(), finish_mutex_); |
| if (is_finished_) { |
| return; |
| } |
| is_stopped_ = true; |
| async_stop_ = std::move(a.HandleStopAsynchronously()); |
| } |
| |
| static art::Thread* art_thread() { |
| // TODO(fmayer): Attach the Perfetto producer thread to ART and give it a name. This is |
| // not trivial, we cannot just attach the first time this method is called, because |
| // AttachCurrentThread deadlocks with the ConditionVariable::Wait in WaitForDataSource. |
| // |
| // We should attach the thread as soon as the Client API spawns it, but that needs more |
| // complicated plumbing. |
| return nullptr; |
| } |
| |
| std::vector<std::string> ignored_types() { return ignored_types_; } |
| |
| void Finish() { |
| art::MutexLock lk(art_thread(), finish_mutex_); |
| if (is_stopped_) { |
| async_stop_(); |
| } else { |
| is_finished_ = true; |
| } |
| } |
| |
| private: |
| bool enabled_ = false; |
| bool dump_smaps_ = false; |
| std::vector<std::string> ignored_types_; |
| static art::Thread* self_; |
| |
| art::Mutex finish_mutex_{"perfetto_hprof_ds_mutex", art::LockLevel::kGenericBottomLock}; |
| bool is_finished_ = false; |
| bool is_stopped_ = false; |
| std::function<void()> async_stop_; |
| }; |
| |
| art::Thread* JavaHprofDataSource::self_ = nullptr; |
| |
| |
| void WaitForDataSource(art::Thread* self) { |
| perfetto::TracingInitArgs args; |
| args.backends = perfetto::BackendType::kSystemBackend; |
| perfetto::Tracing::Initialize(args); |
| |
| perfetto::DataSourceDescriptor dsd; |
| dsd.set_name("android.java_hprof"); |
| dsd.set_will_notify_on_stop(true); |
| JavaHprofDataSource::Register(dsd); |
| |
| LOG(INFO) << "waiting for data source"; |
| |
| art::MutexLock lk(self, GetStateMutex()); |
| while (g_state != State::kStart) { |
| GetStateCV().Wait(self); |
| } |
| } |
| |
| class Writer { |
| public: |
| Writer(pid_t parent_pid, JavaHprofDataSource::TraceContext* ctx, uint64_t timestamp) |
| : parent_pid_(parent_pid), ctx_(ctx), timestamp_(timestamp), |
| last_written_(ctx_->written()) {} |
| |
| // Return whether the next call to GetHeapGraph will create a new TracePacket. |
| bool will_create_new_packet() { |
| return !heap_graph_ || ctx_->written() - last_written_ > kPacketSizeThreshold; |
| } |
| |
| perfetto::protos::pbzero::HeapGraph* GetHeapGraph() { |
| if (will_create_new_packet()) { |
| CreateNewHeapGraph(); |
| } |
| return heap_graph_; |
| } |
| |
| void CreateNewHeapGraph() { |
| if (heap_graph_) { |
| heap_graph_->set_continued(true); |
| } |
| Finalize(); |
| |
| uint64_t written = ctx_->written(); |
| |
| trace_packet_ = ctx_->NewTracePacket(); |
| trace_packet_->set_timestamp(timestamp_); |
| heap_graph_ = trace_packet_->set_heap_graph(); |
| heap_graph_->set_pid(parent_pid_); |
| heap_graph_->set_index(index_++); |
| |
| last_written_ = written; |
| } |
| |
| void Finalize() { |
| if (trace_packet_) { |
| trace_packet_->Finalize(); |
| } |
| heap_graph_ = nullptr; |
| } |
| |
| ~Writer() { Finalize(); } |
| |
| private: |
| const pid_t parent_pid_; |
| JavaHprofDataSource::TraceContext* const ctx_; |
| const uint64_t timestamp_; |
| |
| uint64_t last_written_ = 0; |
| |
| perfetto::DataSource<JavaHprofDataSource>::TraceContext::TracePacketHandle |
| trace_packet_; |
| perfetto::protos::pbzero::HeapGraph* heap_graph_ = nullptr; |
| |
| uint64_t index_ = 0; |
| }; |
| |
| class ReferredObjectsFinder { |
| public: |
| explicit ReferredObjectsFinder( |
| std::vector<std::pair<std::string, art::mirror::Object*>>* referred_objects, |
| art::mirror::Object** min_nonnull_ptr) |
| : referred_objects_(referred_objects), min_nonnull_ptr_(min_nonnull_ptr) {} |
| |
| // For art::mirror::Object::VisitReferences. |
| void operator()(art::ObjPtr<art::mirror::Object> obj, art::MemberOffset offset, |
| bool is_static) const |
| REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| if (offset.Uint32Value() == art::mirror::Object::ClassOffset().Uint32Value()) { |
| // Skip shadow$klass pointer. |
| return; |
| } |
| art::mirror::Object* ref = obj->GetFieldObject<art::mirror::Object>(offset); |
| art::ArtField* field; |
| if (is_static) { |
| field = art::ArtField::FindStaticFieldWithOffset(obj->AsClass(), offset.Uint32Value()); |
| } else { |
| field = art::ArtField::FindInstanceFieldWithOffset(obj->GetClass(), offset.Uint32Value()); |
| } |
| std::string field_name = ""; |
| if (field != nullptr) { |
| field_name = field->PrettyField(/*with_type=*/true); |
| } |
| referred_objects_->emplace_back(std::move(field_name), ref); |
| if (!*min_nonnull_ptr_ || (ref && *min_nonnull_ptr_ > ref)) { |
| *min_nonnull_ptr_ = ref; |
| } |
| } |
| |
| void VisitRootIfNonNull(art::mirror::CompressedReference<art::mirror::Object>* root |
| ATTRIBUTE_UNUSED) const {} |
| void VisitRoot(art::mirror::CompressedReference<art::mirror::Object>* root |
| ATTRIBUTE_UNUSED) const {} |
| |
| private: |
| // We can use a raw Object* pointer here, because there are no concurrent GC threads after the |
| // fork. |
| std::vector<std::pair<std::string, art::mirror::Object*>>* referred_objects_; |
| art::mirror::Object** min_nonnull_ptr_; |
| }; |
| |
| class RootFinder : public art::SingleRootVisitor { |
| public: |
| explicit RootFinder( |
| std::map<art::RootType, std::vector<art::mirror::Object*>>* root_objects) |
| : root_objects_(root_objects) {} |
| |
| void VisitRoot(art::mirror::Object* root, const art::RootInfo& info) override { |
| (*root_objects_)[info.GetType()].emplace_back(root); |
| } |
| |
| private: |
| // We can use a raw Object* pointer here, because there are no concurrent GC threads after the |
| // fork. |
| std::map<art::RootType, std::vector<art::mirror::Object*>>* root_objects_; |
| }; |
| |
| perfetto::protos::pbzero::HeapGraphRoot::Type ToProtoType(art::RootType art_type) { |
| using perfetto::protos::pbzero::HeapGraphRoot; |
| switch (art_type) { |
| case art::kRootUnknown: |
| return HeapGraphRoot::ROOT_UNKNOWN; |
| case art::kRootJNIGlobal: |
| return HeapGraphRoot::ROOT_JNI_GLOBAL; |
| case art::kRootJNILocal: |
| return HeapGraphRoot::ROOT_JNI_LOCAL; |
| case art::kRootJavaFrame: |
| return HeapGraphRoot::ROOT_JAVA_FRAME; |
| case art::kRootNativeStack: |
| return HeapGraphRoot::ROOT_NATIVE_STACK; |
| case art::kRootStickyClass: |
| return HeapGraphRoot::ROOT_STICKY_CLASS; |
| case art::kRootThreadBlock: |
| return HeapGraphRoot::ROOT_THREAD_BLOCK; |
| case art::kRootMonitorUsed: |
| return HeapGraphRoot::ROOT_MONITOR_USED; |
| case art::kRootThreadObject: |
| return HeapGraphRoot::ROOT_THREAD_OBJECT; |
| case art::kRootInternedString: |
| return HeapGraphRoot::ROOT_INTERNED_STRING; |
| case art::kRootFinalizing: |
| return HeapGraphRoot::ROOT_FINALIZING; |
| case art::kRootDebugger: |
| return HeapGraphRoot::ROOT_DEBUGGER; |
| case art::kRootReferenceCleanup: |
| return HeapGraphRoot::ROOT_REFERENCE_CLEANUP; |
| case art::kRootVMInternal: |
| return HeapGraphRoot::ROOT_VM_INTERNAL; |
| case art::kRootJNIMonitor: |
| return HeapGraphRoot::ROOT_JNI_MONITOR; |
| } |
| } |
| |
| perfetto::protos::pbzero::HeapGraphType::Kind ProtoClassKind(uint32_t class_flags) { |
| using perfetto::protos::pbzero::HeapGraphType; |
| switch (class_flags) { |
| case art::mirror::kClassFlagNormal: |
| return HeapGraphType::KIND_NORMAL; |
| case art::mirror::kClassFlagNoReferenceFields: |
| return HeapGraphType::KIND_NOREFERENCES; |
| case art::mirror::kClassFlagString | art::mirror::kClassFlagNoReferenceFields: |
| return HeapGraphType::KIND_STRING; |
| case art::mirror::kClassFlagObjectArray: |
| return HeapGraphType::KIND_ARRAY; |
| case art::mirror::kClassFlagClass: |
| return HeapGraphType::KIND_CLASS; |
| case art::mirror::kClassFlagClassLoader: |
| return HeapGraphType::KIND_CLASSLOADER; |
| case art::mirror::kClassFlagDexCache: |
| return HeapGraphType::KIND_DEXCACHE; |
| case art::mirror::kClassFlagSoftReference: |
| return HeapGraphType::KIND_SOFT_REFERENCE; |
| case art::mirror::kClassFlagWeakReference: |
| return HeapGraphType::KIND_WEAK_REFERENCE; |
| case art::mirror::kClassFlagFinalizerReference: |
| return HeapGraphType::KIND_FINALIZER_REFERENCE; |
| case art::mirror::kClassFlagPhantomReference: |
| return HeapGraphType::KIND_PHANTOM_REFERENCE; |
| default: |
| return HeapGraphType::KIND_UNKNOWN; |
| } |
| } |
| |
| std::string PrettyType(art::mirror::Class* klass) NO_THREAD_SAFETY_ANALYSIS { |
| if (klass == nullptr) { |
| return "(raw)"; |
| } |
| std::string temp; |
| std::string result(art::PrettyDescriptor(klass->GetDescriptor(&temp))); |
| return result; |
| } |
| |
| void DumpSmaps(JavaHprofDataSource::TraceContext* ctx) { |
| FILE* smaps = fopen("/proc/self/smaps", "r"); |
| if (smaps != nullptr) { |
| auto trace_packet = ctx->NewTracePacket(); |
| auto* smaps_packet = trace_packet->set_smaps_packet(); |
| smaps_packet->set_pid(getpid()); |
| perfetto::profiling::ParseSmaps(smaps, |
| [&smaps_packet](const perfetto::profiling::SmapsEntry& e) { |
| if (ShouldSampleSmapsEntry(e)) { |
| auto* smaps_entry = smaps_packet->add_entries(); |
| smaps_entry->set_path(e.pathname); |
| smaps_entry->set_size_kb(e.size_kb); |
| smaps_entry->set_private_dirty_kb(e.private_dirty_kb); |
| smaps_entry->set_swap_kb(e.swap_kb); |
| } |
| }); |
| fclose(smaps); |
| } else { |
| PLOG(ERROR) << "failed to open smaps"; |
| } |
| } |
| |
| uint64_t GetObjectId(const art::mirror::Object* obj) { |
| return reinterpret_cast<uint64_t>(obj) / std::alignment_of<art::mirror::Object>::value; |
| } |
| |
| template <typename F> |
| void ForInstanceReferenceField(art::mirror::Class* klass, F fn) NO_THREAD_SAFETY_ANALYSIS { |
| for (art::ArtField& af : klass->GetIFields()) { |
| if (af.IsPrimitiveType() || |
| af.GetOffset().Uint32Value() == art::mirror::Object::ClassOffset().Uint32Value()) { |
| continue; |
| } |
| fn(af.GetOffset()); |
| } |
| } |
| |
| bool IsIgnored(const std::vector<std::string>& ignored_types, |
| art::mirror::Object* obj) NO_THREAD_SAFETY_ANALYSIS { |
| if (obj->IsClass()) { |
| return false; |
| } |
| art::mirror::Class* klass = obj->GetClass(); |
| return std::find(ignored_types.begin(), ignored_types.end(), PrettyType(klass)) != |
| ignored_types.end(); |
| } |
| |
| size_t EncodedSize(uint64_t n) { |
| if (n == 0) return 1; |
| return 1 + static_cast<size_t>(art::MostSignificantBit(n)) / 7; |
| } |
| |
| void DumpPerfetto(art::Thread* self) { |
| pid_t parent_pid = getpid(); |
| LOG(INFO) << "preparing to dump heap for " << parent_pid; |
| |
| // Need to take a heap dump while GC isn't running. See the comment in |
| // Heap::VisitObjects(). Also we need the critical section to avoid visiting |
| // the same object twice. See b/34967844. |
| // |
| // We need to do this before the fork, because otherwise it can deadlock |
| // waiting for the GC, as all other threads get terminated by the clone, but |
| // their locks are not released. |
| // This does not perfectly solve all fork-related issues, as there could still be threads that |
| // are unaffected by ScopedSuspendAll and in a non-fork-friendly situation |
| // (e.g. inside a malloc holding a lock). This situation is quite rare, and in that case we will |
| // hit the watchdog in the grand-child process if it gets stuck. |
| std::optional<art::gc::ScopedGCCriticalSection> gcs(std::in_place, self, art::gc::kGcCauseHprof, |
| art::gc::kCollectorTypeHprof); |
| |
| std::optional<art::ScopedSuspendAll> ssa(std::in_place, __FUNCTION__, /* long_suspend=*/ true); |
| |
| pid_t pid = fork(); |
| if (pid == -1) { |
| // Fork error. |
| PLOG(ERROR) << "fork"; |
| return; |
| } |
| if (pid != 0) { |
| // Parent |
| // Stop the thread suspension as soon as possible to allow the rest of the application to |
| // continue while we waitpid here. |
| ssa.reset(); |
| gcs.reset(); |
| for (size_t i = 0;; ++i) { |
| if (i == 1000) { |
| // The child hasn't exited for 1 second (and all it was supposed to do was fork itself). |
| // Give up and SIGKILL it. The next waitpid should succeed. |
| LOG(ERROR) << "perfetto_hprof child timed out. Sending SIGKILL."; |
| kill(pid, SIGKILL); |
| } |
| // Busy waiting here will introduce some extra latency, but that is okay because we have |
| // already unsuspended all other threads. This runs on the perfetto_hprof_listener, which |
| // is not needed for progress of the app itself. |
| int stat_loc; |
| pid_t wait_result = waitpid(pid, &stat_loc, WNOHANG); |
| if (wait_result == -1 && errno != EINTR) { |
| if (errno != ECHILD) { |
| // This hopefully never happens (should only be EINVAL). |
| PLOG(FATAL_WITHOUT_ABORT) << "waitpid"; |
| } |
| // If we get ECHILD, the parent process was handling SIGCHLD, or did a wildcard wait. |
| // The child is no longer here either way, so that's good enough for us. |
| break; |
| } else if (wait_result > 0) { |
| break; |
| } else { // wait_result == 0 || errno == EINTR. |
| usleep(1000); |
| } |
| } |
| return; |
| } |
| |
| // The following code is only executed by the child of the original process. |
| |
| // Uninstall signal handler, so we don't trigger a profile on it. |
| if (sigaction(kJavaHeapprofdSignal, &g_orig_act, nullptr) != 0) { |
| close(g_signal_pipe_fds[0]); |
| close(g_signal_pipe_fds[1]); |
| PLOG(FATAL) << "Failed to sigaction"; |
| return; |
| } |
| |
| // Daemon creates a new process that is the grand-child of the original process, and exits. |
| if (daemon(0, 0) == -1) { |
| PLOG(FATAL) << "daemon"; |
| } |
| |
| // The following code is only executed by the grand-child of the original process. |
| |
| // Make sure that this is the first thing we do after forking, so if anything |
| // below hangs, the fork will go away from the watchdog. |
| ArmWatchdogOrDie(); |
| |
| struct timespec ts = {}; |
| if (clock_gettime(CLOCK_BOOTTIME, &ts) != 0) { |
| LOG(FATAL) << "Failed to get boottime."; |
| } |
| uint64_t timestamp = ts.tv_sec * 1000000000LL + ts.tv_nsec; |
| |
| WaitForDataSource(self); |
| |
| JavaHprofDataSource::Trace( |
| [parent_pid, timestamp](JavaHprofDataSource::TraceContext ctx) |
| NO_THREAD_SAFETY_ANALYSIS { |
| bool dump_smaps; |
| std::vector<std::string> ignored_types; |
| { |
| auto ds = ctx.GetDataSourceLocked(); |
| if (!ds || !ds->enabled()) { |
| if (ds) ds->Finish(); |
| LOG(INFO) << "skipping irrelevant data source."; |
| return; |
| } |
| dump_smaps = ds->dump_smaps(); |
| ignored_types = ds->ignored_types(); |
| } |
| LOG(INFO) << "dumping heap for " << parent_pid; |
| if (dump_smaps) { |
| DumpSmaps(&ctx); |
| } |
| Writer writer(parent_pid, &ctx, timestamp); |
| // Make sure that intern ID 0 (default proto value for a uint64_t) always maps to "" |
| // (default proto value for a string). |
| std::map<std::string, uint64_t> interned_fields{{"", 0}}; |
| std::map<std::string, uint64_t> interned_locations{{"", 0}}; |
| std::map<uintptr_t, uint64_t> interned_classes{{0, 0}}; |
| |
| std::map<art::RootType, std::vector<art::mirror::Object*>> root_objects; |
| RootFinder rcf(&root_objects); |
| art::Runtime::Current()->VisitRoots(&rcf); |
| std::unique_ptr<protozero::PackedVarInt> object_ids( |
| new protozero::PackedVarInt); |
| for (const auto& p : root_objects) { |
| const art::RootType root_type = p.first; |
| const std::vector<art::mirror::Object*>& children = p.second; |
| perfetto::protos::pbzero::HeapGraphRoot* root_proto = |
| writer.GetHeapGraph()->add_roots(); |
| root_proto->set_root_type(ToProtoType(root_type)); |
| for (art::mirror::Object* obj : children) { |
| if (writer.will_create_new_packet()) { |
| root_proto->set_object_ids(*object_ids); |
| object_ids->Reset(); |
| root_proto = writer.GetHeapGraph()->add_roots(); |
| root_proto->set_root_type(ToProtoType(root_type)); |
| } |
| object_ids->Append(GetObjectId(obj)); |
| } |
| root_proto->set_object_ids(*object_ids); |
| object_ids->Reset(); |
| } |
| |
| std::unique_ptr<protozero::PackedVarInt> reference_field_ids( |
| new protozero::PackedVarInt); |
| std::unique_ptr<protozero::PackedVarInt> reference_object_ids( |
| new protozero::PackedVarInt); |
| |
| uint64_t prev_object_id = 0; |
| |
| art::Runtime::Current()->GetHeap()->VisitObjectsPaused( |
| [&writer, &interned_fields, &interned_locations, &reference_field_ids, |
| &reference_object_ids, &interned_classes, &ignored_types, &prev_object_id]( |
| art::mirror::Object* obj) REQUIRES_SHARED(art::Locks::mutator_lock_) { |
| if (obj->IsClass()) { |
| art::mirror::Class* klass = obj->AsClass().Ptr(); |
| perfetto::protos::pbzero::HeapGraphType* type_proto = |
| writer.GetHeapGraph()->add_types(); |
| type_proto->set_id(FindOrAppend(&interned_classes, |
| reinterpret_cast<uintptr_t>(klass))); |
| type_proto->set_class_name(PrettyType(klass)); |
| type_proto->set_location_id(FindOrAppend(&interned_locations, |
| klass->GetLocation())); |
| type_proto->set_object_size(klass->GetObjectSize()); |
| type_proto->set_kind(ProtoClassKind(klass->GetClassFlags())); |
| type_proto->set_classloader_id(GetObjectId(klass->GetClassLoader().Ptr())); |
| if (klass->GetSuperClass().Ptr()) { |
| type_proto->set_superclass_id( |
| FindOrAppend(&interned_classes, |
| reinterpret_cast<uintptr_t>(klass->GetSuperClass().Ptr()))); |
| } |
| ForInstanceReferenceField( |
| klass, [klass, &reference_field_ids, &interned_fields]( |
| art::MemberOffset offset) NO_THREAD_SAFETY_ANALYSIS { |
| auto art_field = art::ArtField::FindInstanceFieldWithOffset( |
| klass, offset.Uint32Value()); |
| reference_field_ids->Append( |
| FindOrAppend(&interned_fields, art_field->PrettyField(true))); |
| }); |
| type_proto->set_reference_field_id(*reference_field_ids); |
| reference_field_ids->Reset(); |
| } |
| |
| art::mirror::Class* klass = obj->GetClass(); |
| uintptr_t class_ptr = reinterpret_cast<uintptr_t>(klass); |
| // We need to synethesize a new type for Class<Foo>, which does not exist |
| // in the runtime. Otherwise, all the static members of all classes would be |
| // attributed to java.lang.Class. |
| if (klass->IsClassClass()) { |
| CHECK(obj->IsClass()); |
| perfetto::protos::pbzero::HeapGraphType* type_proto = |
| writer.GetHeapGraph()->add_types(); |
| // All pointers are at least multiples of two, so this way we can make sure |
| // we are not colliding with a real class. |
| class_ptr = reinterpret_cast<uintptr_t>(obj) | 1; |
| auto class_id = FindOrAppend(&interned_classes, class_ptr); |
| type_proto->set_id(class_id); |
| type_proto->set_class_name(obj->PrettyTypeOf()); |
| type_proto->set_location_id(FindOrAppend(&interned_locations, |
| obj->AsClass()->GetLocation())); |
| } |
| |
| if (IsIgnored(ignored_types, obj)) { |
| return; |
| } |
| |
| auto class_id = FindOrAppend(&interned_classes, class_ptr); |
| |
| uint64_t object_id = GetObjectId(obj); |
| perfetto::protos::pbzero::HeapGraphObject* object_proto = |
| writer.GetHeapGraph()->add_objects(); |
| if (prev_object_id && prev_object_id < object_id) { |
| object_proto->set_id_delta(object_id - prev_object_id); |
| } else { |
| object_proto->set_id(object_id); |
| } |
| prev_object_id = object_id; |
| object_proto->set_type_id(class_id); |
| |
| // Arrays / strings are magic and have an instance dependent size. |
| if (obj->SizeOf() != klass->GetObjectSize()) |
| object_proto->set_self_size(obj->SizeOf()); |
| |
| std::vector<std::pair<std::string, art::mirror::Object*>> |
| referred_objects; |
| art::mirror::Object* min_nonnull_ptr = nullptr; |
| ReferredObjectsFinder objf(&referred_objects, &min_nonnull_ptr); |
| |
| const bool emit_field_ids = |
| klass->GetClassFlags() != art::mirror::kClassFlagObjectArray && |
| klass->GetClassFlags() != art::mirror::kClassFlagNormal; |
| if (klass->GetClassFlags() != art::mirror::kClassFlagNormal) { |
| obj->VisitReferences(objf, art::VoidFunctor()); |
| } else { |
| for (art::mirror::Class* cls = klass; cls != nullptr; |
| cls = cls->GetSuperClass().Ptr()) { |
| ForInstanceReferenceField( |
| cls, [obj, objf](art::MemberOffset offset) NO_THREAD_SAFETY_ANALYSIS { |
| objf(art::ObjPtr<art::mirror::Object>(obj), offset, |
| /*is_static=*/false); |
| }); |
| } |
| } |
| |
| uint64_t bytes_saved = 0; |
| uint64_t base_obj_id = GetObjectId(min_nonnull_ptr); |
| if (base_obj_id) { |
| // We need to decrement the base for object ids so that we can tell apart |
| // null references. |
| base_obj_id--; |
| } |
| if (base_obj_id) { |
| for (auto& p : referred_objects) { |
| art::mirror::Object*& referred_obj = p.second; |
| if (!referred_obj || IsIgnored(ignored_types, referred_obj)) { |
| referred_obj = nullptr; |
| continue; |
| } |
| uint64_t referred_obj_id = GetObjectId(referred_obj); |
| bytes_saved += |
| EncodedSize(referred_obj_id) - EncodedSize(referred_obj_id - base_obj_id); |
| } |
| } |
| |
| // +1 for storing the field id. |
| if (bytes_saved <= EncodedSize(base_obj_id) + 1) { |
| // Subtracting the base ptr gains fewer bytes than it takes to store it. |
| base_obj_id = 0; |
| } |
| |
| for (auto& p : referred_objects) { |
| const std::string& field_name = p.first; |
| art::mirror::Object* referred_obj = p.second; |
| if (emit_field_ids) { |
| reference_field_ids->Append(FindOrAppend(&interned_fields, field_name)); |
| } |
| uint64_t referred_obj_id = GetObjectId(referred_obj); |
| if (referred_obj_id) { |
| referred_obj_id -= base_obj_id; |
| } |
| reference_object_ids->Append(referred_obj_id); |
| } |
| if (emit_field_ids) { |
| object_proto->set_reference_field_id(*reference_field_ids); |
| reference_field_ids->Reset(); |
| } |
| if (base_obj_id) { |
| object_proto->set_reference_field_id_base(base_obj_id); |
| } |
| object_proto->set_reference_object_id(*reference_object_ids); |
| reference_object_ids->Reset(); |
| }); |
| |
| for (const auto& p : interned_locations) { |
| const std::string& str = p.first; |
| uint64_t id = p.second; |
| |
| perfetto::protos::pbzero::InternedString* location_proto = |
| writer.GetHeapGraph()->add_location_names(); |
| location_proto->set_iid(id); |
| location_proto->set_str(reinterpret_cast<const uint8_t*>(str.c_str()), |
| str.size()); |
| } |
| for (const auto& p : interned_fields) { |
| const std::string& str = p.first; |
| uint64_t id = p.second; |
| |
| perfetto::protos::pbzero::InternedString* field_proto = |
| writer.GetHeapGraph()->add_field_names(); |
| field_proto->set_iid(id); |
| field_proto->set_str( |
| reinterpret_cast<const uint8_t*>(str.c_str()), str.size()); |
| } |
| |
| writer.Finalize(); |
| ctx.Flush([] { |
| { |
| art::MutexLock lk(JavaHprofDataSource::art_thread(), GetStateMutex()); |
| g_state = State::kEnd; |
| GetStateCV().Broadcast(JavaHprofDataSource::art_thread()); |
| } |
| }); |
| // Wait for the Flush that will happen on the Perfetto thread. |
| { |
| art::MutexLock lk(JavaHprofDataSource::art_thread(), GetStateMutex()); |
| while (g_state != State::kEnd) { |
| GetStateCV().Wait(JavaHprofDataSource::art_thread()); |
| } |
| } |
| { |
| auto ds = ctx.GetDataSourceLocked(); |
| if (ds) { |
| ds->Finish(); |
| } else { |
| LOG(ERROR) << "datasource timed out (duration_ms + datasource_stop_timeout_ms) " |
| "before dump finished"; |
| } |
| } |
| }); |
| |
| LOG(INFO) << "finished dumping heap for " << parent_pid; |
| // Prevent the atexit handlers to run. We do not want to call cleanup |
| // functions the parent process has registered. However, have functions |
| // registered with `at_quick_exit` (for instance LLVM's code coverage profile |
| // dumping routine) be called before exiting. |
| quick_exit(0); |
| } |
| |
| // The plugin initialization function. |
| extern "C" bool ArtPlugin_Initialize() { |
| if (art::Runtime::Current() == nullptr) { |
| return false; |
| } |
| art::Thread* self = art::Thread::Current(); |
| { |
| art::MutexLock lk(self, GetStateMutex()); |
| if (g_state != State::kUninitialized) { |
| LOG(ERROR) << "perfetto_hprof already initialized. state: " << g_state; |
| return false; |
| } |
| g_state = State::kWaitForListener; |
| } |
| |
| if (pipe2(g_signal_pipe_fds, O_CLOEXEC) == -1) { |
| PLOG(ERROR) << "Failed to pipe"; |
| return false; |
| } |
| |
| struct sigaction act = {}; |
| act.sa_flags = SA_SIGINFO | SA_RESTART; |
| act.sa_sigaction = [](int, siginfo_t* si, void*) { |
| requested_tracing_session_id = si->si_value.sival_int; |
| if (write(g_signal_pipe_fds[1], kByte, sizeof(kByte)) == -1) { |
| PLOG(ERROR) << "Failed to trigger heap dump"; |
| } |
| }; |
| |
| // TODO(fmayer): We can probably use the SignalCatcher thread here to not |
| // have an idle thread. |
| if (sigaction(kJavaHeapprofdSignal, &act, &g_orig_act) != 0) { |
| close(g_signal_pipe_fds[0]); |
| close(g_signal_pipe_fds[1]); |
| PLOG(ERROR) << "Failed to sigaction"; |
| return false; |
| } |
| |
| std::thread th([] { |
| art::Runtime* runtime = art::Runtime::Current(); |
| if (!runtime) { |
| LOG(FATAL_WITHOUT_ABORT) << "no runtime in perfetto_hprof_listener"; |
| return; |
| } |
| if (!runtime->AttachCurrentThread("perfetto_hprof_listener", /*as_daemon=*/ true, |
| runtime->GetSystemThreadGroup(), /*create_peer=*/ false)) { |
| LOG(ERROR) << "failed to attach thread."; |
| { |
| art::MutexLock lk(nullptr, GetStateMutex()); |
| g_state = State::kUninitialized; |
| GetStateCV().Broadcast(nullptr); |
| } |
| |
| return; |
| } |
| art::Thread* self = art::Thread::Current(); |
| if (!self) { |
| LOG(FATAL_WITHOUT_ABORT) << "no thread in perfetto_hprof_listener"; |
| return; |
| } |
| { |
| art::MutexLock lk(self, GetStateMutex()); |
| if (g_state == State::kWaitForListener) { |
| g_state = State::kWaitForStart; |
| GetStateCV().Broadcast(self); |
| } |
| } |
| char buf[1]; |
| for (;;) { |
| int res; |
| do { |
| res = read(g_signal_pipe_fds[0], buf, sizeof(buf)); |
| } while (res == -1 && errno == EINTR); |
| |
| if (res <= 0) { |
| if (res == -1) { |
| PLOG(ERROR) << "failed to read"; |
| } |
| close(g_signal_pipe_fds[0]); |
| return; |
| } |
| |
| perfetto_hprof::DumpPerfetto(self); |
| } |
| }); |
| th.detach(); |
| |
| return true; |
| } |
| |
| extern "C" bool ArtPlugin_Deinitialize() { |
| if (sigaction(kJavaHeapprofdSignal, &g_orig_act, nullptr) != 0) { |
| PLOG(ERROR) << "failed to reset signal handler"; |
| // We cannot close the pipe if the signal handler wasn't unregistered, |
| // to avoid receiving SIGPIPE. |
| return false; |
| } |
| close(g_signal_pipe_fds[1]); |
| |
| art::Thread* self = art::Thread::Current(); |
| art::MutexLock lk(self, GetStateMutex()); |
| // Wait until after the thread was registered to the runtime. This is so |
| // we do not attempt to register it with the runtime after it had been torn |
| // down (ArtPlugin_Deinitialize gets called in the Runtime dtor). |
| while (g_state == State::kWaitForListener) { |
| GetStateCV().Wait(art::Thread::Current()); |
| } |
| g_state = State::kUninitialized; |
| GetStateCV().Broadcast(self); |
| return true; |
| } |
| |
| } // namespace perfetto_hprof |
| |
| namespace perfetto { |
| |
| PERFETTO_DEFINE_DATA_SOURCE_STATIC_MEMBERS(perfetto_hprof::JavaHprofDataSource); |
| |
| } |
