| /* |
| * Copyright (C) 2011 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 "trace.h" |
| |
| #include <sys/uio.h> |
| #include <unistd.h> |
| |
| #define ATRACE_TAG ATRACE_TAG_DALVIK |
| #include "cutils/trace.h" |
| |
| #include "base/casts.h" |
| #include "base/stl_util.h" |
| #include "base/unix_file/fd_file.h" |
| #include "class_linker.h" |
| #include "common_throws.h" |
| #include "debugger.h" |
| #include "dex_file-inl.h" |
| #include "instrumentation.h" |
| #include "mirror/art_method-inl.h" |
| #include "mirror/class-inl.h" |
| #include "mirror/dex_cache-inl.h" |
| #include "mirror/object_array-inl.h" |
| #include "mirror/object-inl.h" |
| #include "os.h" |
| #include "scoped_thread_state_change.h" |
| #include "ScopedLocalRef.h" |
| #include "thread.h" |
| #include "thread_list.h" |
| #include "entrypoints/quick/quick_entrypoints.h" |
| |
| namespace art { |
| |
| // File format: |
| // header |
| // record 0 |
| // record 1 |
| // ... |
| // |
| // Header format: |
| // u4 magic ('SLOW') |
| // u2 version |
| // u2 offset to data |
| // u8 start date/time in usec |
| // u2 record size in bytes (version >= 2 only) |
| // ... padding to 32 bytes |
| // |
| // Record format v1: |
| // u1 thread ID |
| // u4 method ID | method action |
| // u4 time delta since start, in usec |
| // |
| // Record format v2: |
| // u2 thread ID |
| // u4 method ID | method action |
| // u4 time delta since start, in usec |
| // |
| // Record format v3: |
| // u2 thread ID |
| // u4 method ID | method action |
| // u4 time delta since start, in usec |
| // u4 wall time since start, in usec (when clock == "dual" only) |
| // |
| // 32 bits of microseconds is 70 minutes. |
| // |
| // All values are stored in little-endian order. |
| |
| enum TraceAction { |
| kTraceMethodEnter = 0x00, // method entry |
| kTraceMethodExit = 0x01, // method exit |
| kTraceUnroll = 0x02, // method exited by exception unrolling |
| // 0x03 currently unused |
| kTraceMethodActionMask = 0x03, // two bits |
| }; |
| |
| static constexpr uint8_t kOpNewMethod = 1U; |
| static constexpr uint8_t kOpNewThread = 2U; |
| |
| class BuildStackTraceVisitor : public StackVisitor { |
| public: |
| explicit BuildStackTraceVisitor(Thread* thread) : StackVisitor(thread, nullptr), |
| method_trace_(Trace::AllocStackTrace()) {} |
| |
| bool VisitFrame() SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| mirror::ArtMethod* m = GetMethod(); |
| // Ignore runtime frames (in particular callee save). |
| if (!m->IsRuntimeMethod()) { |
| method_trace_->push_back(m); |
| } |
| return true; |
| } |
| |
| // Returns a stack trace where the topmost frame corresponds with the first element of the vector. |
| std::vector<mirror::ArtMethod*>* GetStackTrace() const { |
| return method_trace_; |
| } |
| |
| private: |
| std::vector<mirror::ArtMethod*>* const method_trace_; |
| }; |
| |
| static const char kTraceTokenChar = '*'; |
| static const uint16_t kTraceHeaderLength = 32; |
| static const uint32_t kTraceMagicValue = 0x574f4c53; |
| static const uint16_t kTraceVersionSingleClock = 2; |
| static const uint16_t kTraceVersionDualClock = 3; |
| static const uint16_t kTraceRecordSizeSingleClock = 10; // using v2 |
| static const uint16_t kTraceRecordSizeDualClock = 14; // using v3 with two timestamps |
| |
| TraceClockSource Trace::default_clock_source_ = kDefaultTraceClockSource; |
| |
| Trace* volatile Trace::the_trace_ = nullptr; |
| pthread_t Trace::sampling_pthread_ = 0U; |
| std::unique_ptr<std::vector<mirror::ArtMethod*>> Trace::temp_stack_trace_; |
| |
| static mirror::ArtMethod* DecodeTraceMethodId(uint32_t tmid) { |
| return reinterpret_cast<mirror::ArtMethod*>(tmid & ~kTraceMethodActionMask); |
| } |
| |
| static TraceAction DecodeTraceAction(uint32_t tmid) { |
| return static_cast<TraceAction>(tmid & kTraceMethodActionMask); |
| } |
| |
| static uint32_t EncodeTraceMethodAndAction(mirror::ArtMethod* method, |
| TraceAction action) { |
| uint32_t tmid = PointerToLowMemUInt32(method) | action; |
| DCHECK_EQ(method, DecodeTraceMethodId(tmid)); |
| return tmid; |
| } |
| |
| std::vector<mirror::ArtMethod*>* Trace::AllocStackTrace() { |
| if (temp_stack_trace_.get() != nullptr) { |
| return temp_stack_trace_.release(); |
| } else { |
| return new std::vector<mirror::ArtMethod*>(); |
| } |
| } |
| |
| void Trace::FreeStackTrace(std::vector<mirror::ArtMethod*>* stack_trace) { |
| stack_trace->clear(); |
| temp_stack_trace_.reset(stack_trace); |
| } |
| |
| void Trace::SetDefaultClockSource(TraceClockSource clock_source) { |
| #if defined(__linux__) |
| default_clock_source_ = clock_source; |
| #else |
| if (clock_source != TraceClockSource::kWall) { |
| LOG(WARNING) << "Ignoring tracing request to use CPU time."; |
| } |
| #endif |
| } |
| |
| static uint16_t GetTraceVersion(TraceClockSource clock_source) { |
| return (clock_source == TraceClockSource::kDual) ? kTraceVersionDualClock |
| : kTraceVersionSingleClock; |
| } |
| |
| static uint16_t GetRecordSize(TraceClockSource clock_source) { |
| return (clock_source == TraceClockSource::kDual) ? kTraceRecordSizeDualClock |
| : kTraceRecordSizeSingleClock; |
| } |
| |
| bool Trace::UseThreadCpuClock() { |
| return (clock_source_ == TraceClockSource::kThreadCpu) || |
| (clock_source_ == TraceClockSource::kDual); |
| } |
| |
| bool Trace::UseWallClock() { |
| return (clock_source_ == TraceClockSource::kWall) || |
| (clock_source_ == TraceClockSource::kDual); |
| } |
| |
| void Trace::MeasureClockOverhead() { |
| if (UseThreadCpuClock()) { |
| Thread::Current()->GetCpuMicroTime(); |
| } |
| if (UseWallClock()) { |
| MicroTime(); |
| } |
| } |
| |
| // Compute an average time taken to measure clocks. |
| uint32_t Trace::GetClockOverheadNanoSeconds() { |
| Thread* self = Thread::Current(); |
| uint64_t start = self->GetCpuMicroTime(); |
| |
| for (int i = 4000; i > 0; i--) { |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| MeasureClockOverhead(); |
| } |
| |
| uint64_t elapsed_us = self->GetCpuMicroTime() - start; |
| return static_cast<uint32_t>(elapsed_us / 32); |
| } |
| |
| // TODO: put this somewhere with the big-endian equivalent used by JDWP. |
| static void Append2LE(uint8_t* buf, uint16_t val) { |
| *buf++ = static_cast<uint8_t>(val); |
| *buf++ = static_cast<uint8_t>(val >> 8); |
| } |
| |
| // TODO: put this somewhere with the big-endian equivalent used by JDWP. |
| static void Append4LE(uint8_t* buf, uint32_t val) { |
| *buf++ = static_cast<uint8_t>(val); |
| *buf++ = static_cast<uint8_t>(val >> 8); |
| *buf++ = static_cast<uint8_t>(val >> 16); |
| *buf++ = static_cast<uint8_t>(val >> 24); |
| } |
| |
| // TODO: put this somewhere with the big-endian equivalent used by JDWP. |
| static void Append8LE(uint8_t* buf, uint64_t val) { |
| *buf++ = static_cast<uint8_t>(val); |
| *buf++ = static_cast<uint8_t>(val >> 8); |
| *buf++ = static_cast<uint8_t>(val >> 16); |
| *buf++ = static_cast<uint8_t>(val >> 24); |
| *buf++ = static_cast<uint8_t>(val >> 32); |
| *buf++ = static_cast<uint8_t>(val >> 40); |
| *buf++ = static_cast<uint8_t>(val >> 48); |
| *buf++ = static_cast<uint8_t>(val >> 56); |
| } |
| |
| static void GetSample(Thread* thread, void* arg) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| BuildStackTraceVisitor build_trace_visitor(thread); |
| build_trace_visitor.WalkStack(); |
| std::vector<mirror::ArtMethod*>* stack_trace = build_trace_visitor.GetStackTrace(); |
| Trace* the_trace = reinterpret_cast<Trace*>(arg); |
| the_trace->CompareAndUpdateStackTrace(thread, stack_trace); |
| } |
| |
| static void ClearThreadStackTraceAndClockBase(Thread* thread, void* arg ATTRIBUTE_UNUSED) { |
| thread->SetTraceClockBase(0); |
| std::vector<mirror::ArtMethod*>* stack_trace = thread->GetStackTraceSample(); |
| thread->SetStackTraceSample(nullptr); |
| delete stack_trace; |
| } |
| |
| void Trace::CompareAndUpdateStackTrace(Thread* thread, |
| std::vector<mirror::ArtMethod*>* stack_trace) { |
| CHECK_EQ(pthread_self(), sampling_pthread_); |
| std::vector<mirror::ArtMethod*>* old_stack_trace = thread->GetStackTraceSample(); |
| // Update the thread's stack trace sample. |
| thread->SetStackTraceSample(stack_trace); |
| // Read timer clocks to use for all events in this trace. |
| uint32_t thread_clock_diff = 0; |
| uint32_t wall_clock_diff = 0; |
| ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); |
| if (old_stack_trace == nullptr) { |
| // If there's no previous stack trace sample for this thread, log an entry event for all |
| // methods in the trace. |
| for (std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); |
| rit != stack_trace->rend(); ++rit) { |
| LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, |
| thread_clock_diff, wall_clock_diff); |
| } |
| } else { |
| // If there's a previous stack trace for this thread, diff the traces and emit entry and exit |
| // events accordingly. |
| std::vector<mirror::ArtMethod*>::reverse_iterator old_rit = old_stack_trace->rbegin(); |
| std::vector<mirror::ArtMethod*>::reverse_iterator rit = stack_trace->rbegin(); |
| // Iterate bottom-up over both traces until there's a difference between them. |
| while (old_rit != old_stack_trace->rend() && rit != stack_trace->rend() && *old_rit == *rit) { |
| old_rit++; |
| rit++; |
| } |
| // Iterate top-down over the old trace until the point where they differ, emitting exit events. |
| for (std::vector<mirror::ArtMethod*>::iterator old_it = old_stack_trace->begin(); |
| old_it != old_rit.base(); ++old_it) { |
| LogMethodTraceEvent(thread, *old_it, instrumentation::Instrumentation::kMethodExited, |
| thread_clock_diff, wall_clock_diff); |
| } |
| // Iterate bottom-up over the new trace from the point where they differ, emitting entry events. |
| for (; rit != stack_trace->rend(); ++rit) { |
| LogMethodTraceEvent(thread, *rit, instrumentation::Instrumentation::kMethodEntered, |
| thread_clock_diff, wall_clock_diff); |
| } |
| FreeStackTrace(old_stack_trace); |
| } |
| } |
| |
| void* Trace::RunSamplingThread(void* arg) { |
| Runtime* runtime = Runtime::Current(); |
| intptr_t interval_us = reinterpret_cast<intptr_t>(arg); |
| CHECK_GE(interval_us, 0); |
| CHECK(runtime->AttachCurrentThread("Sampling Profiler", true, runtime->GetSystemThreadGroup(), |
| !runtime->IsAotCompiler())); |
| |
| while (true) { |
| usleep(interval_us); |
| ATRACE_BEGIN("Profile sampling"); |
| Thread* self = Thread::Current(); |
| Trace* the_trace; |
| { |
| MutexLock mu(self, *Locks::trace_lock_); |
| the_trace = the_trace_; |
| if (the_trace == nullptr) { |
| break; |
| } |
| } |
| |
| runtime->GetThreadList()->SuspendAll(__FUNCTION__); |
| { |
| MutexLock mu(self, *Locks::thread_list_lock_); |
| runtime->GetThreadList()->ForEach(GetSample, the_trace); |
| } |
| runtime->GetThreadList()->ResumeAll(); |
| ATRACE_END(); |
| } |
| |
| runtime->DetachCurrentThread(); |
| return nullptr; |
| } |
| |
| void Trace::Start(const char* trace_filename, int trace_fd, size_t buffer_size, int flags, |
| TraceOutputMode output_mode, TraceMode trace_mode, int interval_us) { |
| Thread* self = Thread::Current(); |
| { |
| MutexLock mu(self, *Locks::trace_lock_); |
| if (the_trace_ != nullptr) { |
| LOG(ERROR) << "Trace already in progress, ignoring this request"; |
| return; |
| } |
| } |
| |
| // Check interval if sampling is enabled |
| if (trace_mode == TraceMode::kSampling && interval_us <= 0) { |
| LOG(ERROR) << "Invalid sampling interval: " << interval_us; |
| ScopedObjectAccess soa(self); |
| ThrowRuntimeException("Invalid sampling interval: %d", interval_us); |
| return; |
| } |
| |
| // Open trace file if not going directly to ddms. |
| std::unique_ptr<File> trace_file; |
| if (output_mode != TraceOutputMode::kDDMS) { |
| if (trace_fd < 0) { |
| trace_file.reset(OS::CreateEmptyFile(trace_filename)); |
| } else { |
| trace_file.reset(new File(trace_fd, "tracefile")); |
| trace_file->DisableAutoClose(); |
| } |
| if (trace_file.get() == nullptr) { |
| PLOG(ERROR) << "Unable to open trace file '" << trace_filename << "'"; |
| ScopedObjectAccess soa(self); |
| ThrowRuntimeException("Unable to open trace file '%s'", trace_filename); |
| return; |
| } |
| } |
| |
| Runtime* runtime = Runtime::Current(); |
| |
| // Enable count of allocs if specified in the flags. |
| bool enable_stats = false; |
| |
| runtime->GetThreadList()->SuspendAll(__FUNCTION__); |
| |
| // Create Trace object. |
| { |
| MutexLock mu(self, *Locks::trace_lock_); |
| if (the_trace_ != nullptr) { |
| LOG(ERROR) << "Trace already in progress, ignoring this request"; |
| } else { |
| enable_stats = (flags && kTraceCountAllocs) != 0; |
| the_trace_ = new Trace(trace_file.release(), trace_filename, buffer_size, flags, output_mode, |
| trace_mode); |
| if (trace_mode == TraceMode::kSampling) { |
| CHECK_PTHREAD_CALL(pthread_create, (&sampling_pthread_, nullptr, &RunSamplingThread, |
| reinterpret_cast<void*>(interval_us)), |
| "Sampling profiler thread"); |
| the_trace_->interval_us_ = interval_us; |
| } else { |
| runtime->GetInstrumentation()->AddListener(the_trace_, |
| instrumentation::Instrumentation::kMethodEntered | |
| instrumentation::Instrumentation::kMethodExited | |
| instrumentation::Instrumentation::kMethodUnwind); |
| // TODO: In full-PIC mode, we don't need to fully deopt. |
| runtime->GetInstrumentation()->EnableMethodTracing(); |
| } |
| } |
| } |
| |
| runtime->GetThreadList()->ResumeAll(); |
| |
| // Can't call this when holding the mutator lock. |
| if (enable_stats) { |
| runtime->SetStatsEnabled(true); |
| } |
| } |
| |
| void Trace::StopTracing(bool finish_tracing, bool flush_file) { |
| bool stop_alloc_counting = false; |
| Runtime* const runtime = Runtime::Current(); |
| Trace* the_trace = nullptr; |
| pthread_t sampling_pthread = 0U; |
| { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| if (the_trace_ == nullptr) { |
| LOG(ERROR) << "Trace stop requested, but no trace currently running"; |
| } else { |
| the_trace = the_trace_; |
| the_trace_ = nullptr; |
| sampling_pthread = sampling_pthread_; |
| } |
| } |
| // Make sure that we join before we delete the trace since we don't want to have |
| // the sampling thread access a stale pointer. This finishes since the sampling thread exits when |
| // the_trace_ is null. |
| if (sampling_pthread != 0U) { |
| CHECK_PTHREAD_CALL(pthread_join, (sampling_pthread, nullptr), "sampling thread shutdown"); |
| sampling_pthread_ = 0U; |
| } |
| runtime->GetThreadList()->SuspendAll(__FUNCTION__); |
| |
| if (the_trace != nullptr) { |
| stop_alloc_counting = (the_trace->flags_ & Trace::kTraceCountAllocs) != 0; |
| if (finish_tracing) { |
| the_trace->FinishTracing(); |
| } |
| |
| if (the_trace->trace_mode_ == TraceMode::kSampling) { |
| MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); |
| runtime->GetThreadList()->ForEach(ClearThreadStackTraceAndClockBase, nullptr); |
| } else { |
| runtime->GetInstrumentation()->DisableMethodTracing(); |
| runtime->GetInstrumentation()->RemoveListener( |
| the_trace, instrumentation::Instrumentation::kMethodEntered | |
| instrumentation::Instrumentation::kMethodExited | |
| instrumentation::Instrumentation::kMethodUnwind); |
| } |
| if (the_trace->trace_file_.get() != nullptr) { |
| // Do not try to erase, so flush and close explicitly. |
| if (flush_file) { |
| if (the_trace->trace_file_->Flush() != 0) { |
| PLOG(ERROR) << "Could not flush trace file."; |
| } |
| } else { |
| the_trace->trace_file_->MarkUnchecked(); // Do not trigger guard. |
| } |
| if (the_trace->trace_file_->Close() != 0) { |
| PLOG(ERROR) << "Could not close trace file."; |
| } |
| } |
| delete the_trace; |
| } |
| runtime->GetThreadList()->ResumeAll(); |
| if (stop_alloc_counting) { |
| // Can be racy since SetStatsEnabled is not guarded by any locks. |
| runtime->SetStatsEnabled(false); |
| } |
| } |
| |
| void Trace::Abort() { |
| // Do not write anything anymore. |
| StopTracing(false, false); |
| } |
| |
| void Trace::Stop() { |
| // Finish writing. |
| StopTracing(true, true); |
| } |
| |
| void Trace::Shutdown() { |
| if (GetMethodTracingMode() != kTracingInactive) { |
| Stop(); |
| } |
| } |
| |
| void Trace::Pause() { |
| bool stop_alloc_counting = false; |
| Runtime* runtime = Runtime::Current(); |
| Trace* the_trace = nullptr; |
| |
| pthread_t sampling_pthread = 0U; |
| { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| if (the_trace_ == nullptr) { |
| LOG(ERROR) << "Trace pause requested, but no trace currently running"; |
| return; |
| } else { |
| the_trace = the_trace_; |
| sampling_pthread = sampling_pthread_; |
| } |
| } |
| |
| if (sampling_pthread != 0U) { |
| { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| the_trace_ = nullptr; |
| } |
| CHECK_PTHREAD_CALL(pthread_join, (sampling_pthread, nullptr), "sampling thread shutdown"); |
| sampling_pthread_ = 0U; |
| { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| the_trace_ = the_trace; |
| } |
| } |
| |
| if (the_trace != nullptr) { |
| runtime->GetThreadList()->SuspendAll(__FUNCTION__); |
| stop_alloc_counting = (the_trace->flags_ & Trace::kTraceCountAllocs) != 0; |
| |
| if (the_trace->trace_mode_ == TraceMode::kSampling) { |
| MutexLock mu(Thread::Current(), *Locks::thread_list_lock_); |
| runtime->GetThreadList()->ForEach(ClearThreadStackTraceAndClockBase, nullptr); |
| } else { |
| runtime->GetInstrumentation()->DisableMethodTracing(); |
| runtime->GetInstrumentation()->RemoveListener(the_trace, |
| instrumentation::Instrumentation::kMethodEntered | |
| instrumentation::Instrumentation::kMethodExited | |
| instrumentation::Instrumentation::kMethodUnwind); |
| } |
| runtime->GetThreadList()->ResumeAll(); |
| } |
| |
| if (stop_alloc_counting) { |
| // Can be racy since SetStatsEnabled is not guarded by any locks. |
| Runtime::Current()->SetStatsEnabled(false); |
| } |
| } |
| |
| void Trace::Resume() { |
| Thread* self = Thread::Current(); |
| Trace* the_trace; |
| { |
| MutexLock mu(self, *Locks::trace_lock_); |
| if (the_trace_ == nullptr) { |
| LOG(ERROR) << "No trace to resume (or sampling mode), ignoring this request"; |
| return; |
| } |
| the_trace = the_trace_; |
| } |
| |
| Runtime* runtime = Runtime::Current(); |
| |
| // Enable count of allocs if specified in the flags. |
| bool enable_stats = (the_trace->flags_ && kTraceCountAllocs) != 0; |
| |
| runtime->GetThreadList()->SuspendAll(__FUNCTION__); |
| |
| // Reenable. |
| if (the_trace->trace_mode_ == TraceMode::kSampling) { |
| CHECK_PTHREAD_CALL(pthread_create, (&sampling_pthread_, nullptr, &RunSamplingThread, |
| reinterpret_cast<void*>(the_trace->interval_us_)), "Sampling profiler thread"); |
| } else { |
| runtime->GetInstrumentation()->AddListener(the_trace, |
| instrumentation::Instrumentation::kMethodEntered | |
| instrumentation::Instrumentation::kMethodExited | |
| instrumentation::Instrumentation::kMethodUnwind); |
| // TODO: In full-PIC mode, we don't need to fully deopt. |
| runtime->GetInstrumentation()->EnableMethodTracing(); |
| } |
| |
| runtime->GetThreadList()->ResumeAll(); |
| |
| // Can't call this when holding the mutator lock. |
| if (enable_stats) { |
| runtime->SetStatsEnabled(true); |
| } |
| } |
| |
| TracingMode Trace::GetMethodTracingMode() { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| if (the_trace_ == nullptr) { |
| return kTracingInactive; |
| } else { |
| switch (the_trace_->trace_mode_) { |
| case TraceMode::kSampling: |
| return kSampleProfilingActive; |
| case TraceMode::kMethodTracing: |
| return kMethodTracingActive; |
| } |
| LOG(FATAL) << "Unreachable"; |
| UNREACHABLE(); |
| } |
| } |
| |
| static constexpr size_t kMinBufSize = 18U; // Trace header is up to 18B. |
| |
| Trace::Trace(File* trace_file, const char* trace_name, size_t buffer_size, int flags, |
| TraceOutputMode output_mode, TraceMode trace_mode) |
| : trace_file_(trace_file), |
| buf_(new uint8_t[std::max(kMinBufSize, buffer_size)]()), |
| flags_(flags), trace_output_mode_(output_mode), trace_mode_(trace_mode), |
| clock_source_(default_clock_source_), |
| buffer_size_(std::max(kMinBufSize, buffer_size)), |
| start_time_(MicroTime()), clock_overhead_ns_(GetClockOverheadNanoSeconds()), cur_offset_(0), |
| overflow_(false), interval_us_(0), streaming_lock_(nullptr) { |
| uint16_t trace_version = GetTraceVersion(clock_source_); |
| if (output_mode == TraceOutputMode::kStreaming) { |
| trace_version |= 0xF0U; |
| } |
| // Set up the beginning of the trace. |
| memset(buf_.get(), 0, kTraceHeaderLength); |
| Append4LE(buf_.get(), kTraceMagicValue); |
| Append2LE(buf_.get() + 4, trace_version); |
| Append2LE(buf_.get() + 6, kTraceHeaderLength); |
| Append8LE(buf_.get() + 8, start_time_); |
| if (trace_version >= kTraceVersionDualClock) { |
| uint16_t record_size = GetRecordSize(clock_source_); |
| Append2LE(buf_.get() + 16, record_size); |
| } |
| static_assert(18 <= kMinBufSize, "Minimum buffer size not large enough for trace header"); |
| |
| // Update current offset. |
| cur_offset_.StoreRelaxed(kTraceHeaderLength); |
| |
| if (output_mode == TraceOutputMode::kStreaming) { |
| streaming_file_name_ = trace_name; |
| streaming_lock_ = new Mutex("tracing lock"); |
| seen_threads_.reset(new ThreadIDBitSet()); |
| } |
| } |
| |
| Trace::~Trace() { |
| delete streaming_lock_; |
| } |
| |
| static void DumpBuf(uint8_t* buf, size_t buf_size, TraceClockSource clock_source) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| uint8_t* ptr = buf + kTraceHeaderLength; |
| uint8_t* end = buf + buf_size; |
| |
| while (ptr < end) { |
| uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); |
| mirror::ArtMethod* method = DecodeTraceMethodId(tmid); |
| TraceAction action = DecodeTraceAction(tmid); |
| LOG(INFO) << PrettyMethod(method) << " " << static_cast<int>(action); |
| ptr += GetRecordSize(clock_source); |
| } |
| } |
| |
| static void GetVisitedMethodsFromBitSets( |
| const std::map<mirror::DexCache*, DexIndexBitSet*>& seen_methods, |
| std::set<mirror::ArtMethod*>* visited_methods) SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| for (auto& e : seen_methods) { |
| DexIndexBitSet* bit_set = e.second; |
| for (uint32_t i = 0; i < bit_set->size(); ++i) { |
| if ((*bit_set)[i]) { |
| visited_methods->insert(e.first->GetResolvedMethod(i)); |
| } |
| } |
| } |
| } |
| |
| void Trace::FinishTracing() { |
| size_t final_offset = 0; |
| |
| std::set<mirror::ArtMethod*> visited_methods; |
| if (trace_output_mode_ == TraceOutputMode::kStreaming) { |
| // Write the secondary file with all the method names. |
| GetVisitedMethodsFromBitSets(seen_methods_, &visited_methods); |
| |
| // Clean up. |
| for (auto& e : seen_methods_) { |
| delete e.second; |
| } |
| } else { |
| final_offset = cur_offset_.LoadRelaxed(); |
| GetVisitedMethods(final_offset, &visited_methods); |
| } |
| |
| // Compute elapsed time. |
| uint64_t elapsed = MicroTime() - start_time_; |
| |
| std::ostringstream os; |
| |
| os << StringPrintf("%cversion\n", kTraceTokenChar); |
| os << StringPrintf("%d\n", GetTraceVersion(clock_source_)); |
| os << StringPrintf("data-file-overflow=%s\n", overflow_ ? "true" : "false"); |
| if (UseThreadCpuClock()) { |
| if (UseWallClock()) { |
| os << StringPrintf("clock=dual\n"); |
| } else { |
| os << StringPrintf("clock=thread-cpu\n"); |
| } |
| } else { |
| os << StringPrintf("clock=wall\n"); |
| } |
| os << StringPrintf("elapsed-time-usec=%" PRIu64 "\n", elapsed); |
| if (trace_output_mode_ != TraceOutputMode::kStreaming) { |
| size_t num_records = (final_offset - kTraceHeaderLength) / GetRecordSize(clock_source_); |
| os << StringPrintf("num-method-calls=%zd\n", num_records); |
| } |
| os << StringPrintf("clock-call-overhead-nsec=%d\n", clock_overhead_ns_); |
| os << StringPrintf("vm=art\n"); |
| os << StringPrintf("pid=%d\n", getpid()); |
| if ((flags_ & kTraceCountAllocs) != 0) { |
| os << StringPrintf("alloc-count=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_OBJECTS)); |
| os << StringPrintf("alloc-size=%d\n", Runtime::Current()->GetStat(KIND_ALLOCATED_BYTES)); |
| os << StringPrintf("gc-count=%d\n", Runtime::Current()->GetStat(KIND_GC_INVOCATIONS)); |
| } |
| os << StringPrintf("%cthreads\n", kTraceTokenChar); |
| DumpThreadList(os); |
| os << StringPrintf("%cmethods\n", kTraceTokenChar); |
| DumpMethodList(os, visited_methods); |
| os << StringPrintf("%cend\n", kTraceTokenChar); |
| std::string header(os.str()); |
| |
| if (trace_output_mode_ == TraceOutputMode::kStreaming) { |
| File file; |
| if (!file.Open(streaming_file_name_ + ".sec", O_CREAT | O_WRONLY)) { |
| LOG(WARNING) << "Could not open secondary trace file!"; |
| return; |
| } |
| if (!file.WriteFully(header.c_str(), header.length())) { |
| file.Erase(); |
| std::string detail(StringPrintf("Trace data write failed: %s", strerror(errno))); |
| PLOG(ERROR) << detail; |
| ThrowRuntimeException("%s", detail.c_str()); |
| } |
| if (file.FlushCloseOrErase() != 0) { |
| PLOG(ERROR) << "Could not write secondary file"; |
| } |
| } else { |
| if (trace_file_.get() == nullptr) { |
| iovec iov[2]; |
| iov[0].iov_base = reinterpret_cast<void*>(const_cast<char*>(header.c_str())); |
| iov[0].iov_len = header.length(); |
| iov[1].iov_base = buf_.get(); |
| iov[1].iov_len = final_offset; |
| Dbg::DdmSendChunkV(CHUNK_TYPE("MPSE"), iov, 2); |
| const bool kDumpTraceInfo = false; |
| if (kDumpTraceInfo) { |
| LOG(INFO) << "Trace sent:\n" << header; |
| DumpBuf(buf_.get(), final_offset, clock_source_); |
| } |
| } else { |
| if (!trace_file_->WriteFully(header.c_str(), header.length()) || |
| !trace_file_->WriteFully(buf_.get(), final_offset)) { |
| std::string detail(StringPrintf("Trace data write failed: %s", strerror(errno))); |
| PLOG(ERROR) << detail; |
| ThrowRuntimeException("%s", detail.c_str()); |
| } |
| } |
| } |
| } |
| |
| void Trace::DexPcMoved(Thread* thread, mirror::Object* this_object, |
| mirror::ArtMethod* method, uint32_t new_dex_pc) { |
| UNUSED(thread, this_object, method, new_dex_pc); |
| // We're not recorded to listen to this kind of event, so complain. |
| LOG(ERROR) << "Unexpected dex PC event in tracing " << PrettyMethod(method) << " " << new_dex_pc; |
| } |
| |
| void Trace::FieldRead(Thread* thread, mirror::Object* this_object, |
| mirror::ArtMethod* method, uint32_t dex_pc, ArtField* field) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| UNUSED(thread, this_object, method, dex_pc, field); |
| // We're not recorded to listen to this kind of event, so complain. |
| LOG(ERROR) << "Unexpected field read event in tracing " << PrettyMethod(method) << " " << dex_pc; |
| } |
| |
| void Trace::FieldWritten(Thread* thread, mirror::Object* this_object, |
| mirror::ArtMethod* method, uint32_t dex_pc, ArtField* field, |
| const JValue& field_value) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| UNUSED(thread, this_object, method, dex_pc, field, field_value); |
| // We're not recorded to listen to this kind of event, so complain. |
| LOG(ERROR) << "Unexpected field write event in tracing " << PrettyMethod(method) << " " << dex_pc; |
| } |
| |
| void Trace::MethodEntered(Thread* thread, mirror::Object* this_object ATTRIBUTE_UNUSED, |
| mirror::ArtMethod* method, uint32_t dex_pc ATTRIBUTE_UNUSED) { |
| uint32_t thread_clock_diff = 0; |
| uint32_t wall_clock_diff = 0; |
| ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); |
| LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodEntered, |
| thread_clock_diff, wall_clock_diff); |
| } |
| |
| void Trace::MethodExited(Thread* thread, mirror::Object* this_object ATTRIBUTE_UNUSED, |
| mirror::ArtMethod* method, uint32_t dex_pc ATTRIBUTE_UNUSED, |
| const JValue& return_value ATTRIBUTE_UNUSED) { |
| uint32_t thread_clock_diff = 0; |
| uint32_t wall_clock_diff = 0; |
| ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); |
| LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodExited, |
| thread_clock_diff, wall_clock_diff); |
| } |
| |
| void Trace::MethodUnwind(Thread* thread, mirror::Object* this_object ATTRIBUTE_UNUSED, |
| mirror::ArtMethod* method, uint32_t dex_pc ATTRIBUTE_UNUSED) { |
| uint32_t thread_clock_diff = 0; |
| uint32_t wall_clock_diff = 0; |
| ReadClocks(thread, &thread_clock_diff, &wall_clock_diff); |
| LogMethodTraceEvent(thread, method, instrumentation::Instrumentation::kMethodUnwind, |
| thread_clock_diff, wall_clock_diff); |
| } |
| |
| void Trace::ExceptionCaught(Thread* thread, mirror::Throwable* exception_object) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| UNUSED(thread, exception_object); |
| LOG(ERROR) << "Unexpected exception caught event in tracing"; |
| } |
| |
| void Trace::BackwardBranch(Thread* /*thread*/, mirror::ArtMethod* method, |
| int32_t /*dex_pc_offset*/) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| LOG(ERROR) << "Unexpected backward branch event in tracing" << PrettyMethod(method); |
| } |
| |
| void Trace::ReadClocks(Thread* thread, uint32_t* thread_clock_diff, uint32_t* wall_clock_diff) { |
| if (UseThreadCpuClock()) { |
| uint64_t clock_base = thread->GetTraceClockBase(); |
| if (UNLIKELY(clock_base == 0)) { |
| // First event, record the base time in the map. |
| uint64_t time = thread->GetCpuMicroTime(); |
| thread->SetTraceClockBase(time); |
| } else { |
| *thread_clock_diff = thread->GetCpuMicroTime() - clock_base; |
| } |
| } |
| if (UseWallClock()) { |
| *wall_clock_diff = MicroTime() - start_time_; |
| } |
| } |
| |
| bool Trace::RegisterMethod(mirror::ArtMethod* method) { |
| mirror::DexCache* dex_cache = method->GetDexCache(); |
| if (dex_cache->GetResolvedMethod(method->GetDexMethodIndex()) != method) { |
| DCHECK(dex_cache->GetResolvedMethod(method->GetDexMethodIndex()) == nullptr); |
| dex_cache->SetResolvedMethod(method->GetDexMethodIndex(), method); |
| } |
| if (seen_methods_.find(dex_cache) == seen_methods_.end()) { |
| seen_methods_.insert(std::make_pair(dex_cache, new DexIndexBitSet())); |
| } |
| DexIndexBitSet* bit_set = seen_methods_.find(dex_cache)->second; |
| if (!(*bit_set)[method->GetDexMethodIndex()]) { |
| bit_set->set(method->GetDexMethodIndex()); |
| return true; |
| } |
| return false; |
| } |
| |
| bool Trace::RegisterThread(Thread* thread) { |
| pid_t tid = thread->GetTid(); |
| CHECK_LT(0U, static_cast<uint32_t>(tid)); |
| CHECK_LT(static_cast<uint32_t>(tid), 65536U); |
| |
| if (!(*seen_threads_)[tid]) { |
| seen_threads_->set(tid); |
| return true; |
| } |
| return false; |
| } |
| |
| static std::string GetMethodLine(mirror::ArtMethod* method) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| return StringPrintf("%p\t%s\t%s\t%s\t%s\n", method, |
| PrettyDescriptor(method->GetDeclaringClassDescriptor()).c_str(), method->GetName(), |
| method->GetSignature().ToString().c_str(), method->GetDeclaringClassSourceFile()); |
| } |
| |
| void Trace::WriteToBuf(const uint8_t* src, size_t src_size) { |
| int32_t old_offset = cur_offset_.LoadRelaxed(); |
| int32_t new_offset = old_offset + static_cast<int32_t>(src_size); |
| if (dchecked_integral_cast<size_t>(new_offset) > buffer_size_) { |
| // Flush buffer. |
| if (!trace_file_->WriteFully(buf_.get(), old_offset)) { |
| PLOG(WARNING) << "Failed streaming a tracing event."; |
| } |
| |
| // Check whether the data is too large for the buffer, then write immediately. |
| if (src_size >= buffer_size_) { |
| if (!trace_file_->WriteFully(src, src_size)) { |
| PLOG(WARNING) << "Failed streaming a tracing event."; |
| } |
| cur_offset_.StoreRelease(0); // Buffer is empty now. |
| return; |
| } |
| |
| old_offset = 0; |
| new_offset = static_cast<int32_t>(src_size); |
| } |
| cur_offset_.StoreRelease(new_offset); |
| // Fill in data. |
| memcpy(buf_.get() + old_offset, src, src_size); |
| } |
| |
| void Trace::LogMethodTraceEvent(Thread* thread, mirror::ArtMethod* method, |
| instrumentation::Instrumentation::InstrumentationEvent event, |
| uint32_t thread_clock_diff, uint32_t wall_clock_diff) { |
| // Advance cur_offset_ atomically. |
| int32_t new_offset; |
| int32_t old_offset = 0; |
| |
| // We do a busy loop here trying to acquire the next offset. |
| if (trace_output_mode_ != TraceOutputMode::kStreaming) { |
| do { |
| old_offset = cur_offset_.LoadRelaxed(); |
| new_offset = old_offset + GetRecordSize(clock_source_); |
| if (static_cast<size_t>(new_offset) > buffer_size_) { |
| overflow_ = true; |
| return; |
| } |
| } while (!cur_offset_.CompareExchangeWeakSequentiallyConsistent(old_offset, new_offset)); |
| } |
| |
| TraceAction action = kTraceMethodEnter; |
| switch (event) { |
| case instrumentation::Instrumentation::kMethodEntered: |
| action = kTraceMethodEnter; |
| break; |
| case instrumentation::Instrumentation::kMethodExited: |
| action = kTraceMethodExit; |
| break; |
| case instrumentation::Instrumentation::kMethodUnwind: |
| action = kTraceUnroll; |
| break; |
| default: |
| UNIMPLEMENTED(FATAL) << "Unexpected event: " << event; |
| } |
| |
| uint32_t method_value = EncodeTraceMethodAndAction(method, action); |
| |
| // Write data |
| uint8_t* ptr; |
| static constexpr size_t kPacketSize = 14U; // The maximum size of data in a packet. |
| uint8_t stack_buf[kPacketSize]; // Space to store a packet when in streaming mode. |
| if (trace_output_mode_ == TraceOutputMode::kStreaming) { |
| ptr = stack_buf; |
| } else { |
| ptr = buf_.get() + old_offset; |
| } |
| |
| Append2LE(ptr, thread->GetTid()); |
| Append4LE(ptr + 2, method_value); |
| ptr += 6; |
| |
| if (UseThreadCpuClock()) { |
| Append4LE(ptr, thread_clock_diff); |
| ptr += 4; |
| } |
| if (UseWallClock()) { |
| Append4LE(ptr, wall_clock_diff); |
| } |
| static_assert(kPacketSize == 2 + 4 + 4 + 4, "Packet size incorrect."); |
| |
| if (trace_output_mode_ == TraceOutputMode::kStreaming) { |
| MutexLock mu(Thread::Current(), *streaming_lock_); // To serialize writing. |
| if (RegisterMethod(method)) { |
| // Write a special block with the name. |
| std::string method_line(GetMethodLine(method)); |
| uint8_t buf2[5]; |
| Append2LE(buf2, 0); |
| buf2[2] = kOpNewMethod; |
| Append2LE(buf2 + 3, static_cast<uint16_t>(method_line.length())); |
| WriteToBuf(buf2, sizeof(buf2)); |
| WriteToBuf(reinterpret_cast<const uint8_t*>(method_line.c_str()), method_line.length()); |
| } |
| if (RegisterThread(thread)) { |
| // It might be better to postpone this. Threads might not have received names... |
| std::string thread_name; |
| thread->GetThreadName(thread_name); |
| uint8_t buf2[7]; |
| Append2LE(buf2, 0); |
| buf2[2] = kOpNewThread; |
| Append2LE(buf2 + 3, static_cast<uint16_t>(thread->GetTid())); |
| Append2LE(buf2 + 5, static_cast<uint16_t>(thread_name.length())); |
| WriteToBuf(buf2, sizeof(buf2)); |
| WriteToBuf(reinterpret_cast<const uint8_t*>(thread_name.c_str()), thread_name.length()); |
| } |
| WriteToBuf(stack_buf, sizeof(stack_buf)); |
| } |
| } |
| |
| void Trace::GetVisitedMethods(size_t buf_size, |
| std::set<mirror::ArtMethod*>* visited_methods) { |
| uint8_t* ptr = buf_.get() + kTraceHeaderLength; |
| uint8_t* end = buf_.get() + buf_size; |
| |
| while (ptr < end) { |
| uint32_t tmid = ptr[2] | (ptr[3] << 8) | (ptr[4] << 16) | (ptr[5] << 24); |
| mirror::ArtMethod* method = DecodeTraceMethodId(tmid); |
| visited_methods->insert(method); |
| ptr += GetRecordSize(clock_source_); |
| } |
| } |
| |
| void Trace::DumpMethodList(std::ostream& os, const std::set<mirror::ArtMethod*>& visited_methods) { |
| for (const auto& method : visited_methods) { |
| os << GetMethodLine(method); |
| } |
| } |
| |
| static void DumpThread(Thread* t, void* arg) { |
| std::ostream& os = *reinterpret_cast<std::ostream*>(arg); |
| std::string name; |
| t->GetThreadName(name); |
| os << t->GetTid() << "\t" << name << "\n"; |
| } |
| |
| void Trace::DumpThreadList(std::ostream& os) { |
| Thread* self = Thread::Current(); |
| for (auto it : exited_threads_) { |
| os << it.first << "\t" << it.second << "\n"; |
| } |
| Locks::thread_list_lock_->AssertNotHeld(self); |
| MutexLock mu(self, *Locks::thread_list_lock_); |
| Runtime::Current()->GetThreadList()->ForEach(DumpThread, &os); |
| } |
| |
| void Trace::StoreExitingThreadInfo(Thread* thread) { |
| MutexLock mu(thread, *Locks::trace_lock_); |
| if (the_trace_ != nullptr) { |
| std::string name; |
| thread->GetThreadName(name); |
| // The same thread/tid may be used multiple times. As SafeMap::Put does not allow to override |
| // a previous mapping, use SafeMap::Overwrite. |
| the_trace_->exited_threads_.Overwrite(thread->GetTid(), name); |
| } |
| } |
| |
| Trace::TraceOutputMode Trace::GetOutputMode() { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| CHECK(the_trace_ != nullptr) << "Trace output mode requested, but no trace currently running"; |
| return the_trace_->trace_output_mode_; |
| } |
| |
| Trace::TraceMode Trace::GetMode() { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| CHECK(the_trace_ != nullptr) << "Trace mode requested, but no trace currently running"; |
| return the_trace_->trace_mode_; |
| } |
| |
| size_t Trace::GetBufferSize() { |
| MutexLock mu(Thread::Current(), *Locks::trace_lock_); |
| CHECK(the_trace_ != nullptr) << "Trace mode requested, but no trace currently running"; |
| return the_trace_->buffer_size_; |
| } |
| |
| } // namespace art |