| // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| #include "platform/address_sanitizer.h" |
| #include "platform/memory_sanitizer.h" |
| #include "platform/utils.h" |
| |
| #include "platform/atomic.h" |
| #include "vm/allocation.h" |
| #include "vm/code_patcher.h" |
| #include "vm/debugger.h" |
| #include "vm/instructions.h" |
| #include "vm/isolate.h" |
| #include "vm/json_stream.h" |
| #include "vm/lockers.h" |
| #include "vm/message_handler.h" |
| #include "vm/native_symbol.h" |
| #include "vm/object.h" |
| #include "vm/os.h" |
| #include "vm/profiler.h" |
| #include "vm/reusable_handles.h" |
| #include "vm/signal_handler.h" |
| #include "vm/simulator.h" |
| #include "vm/stack_frame.h" |
| #include "vm/version.h" |
| |
| namespace dart { |
| |
| static const intptr_t kSampleSize = 8; |
| static const intptr_t kMaxSamplesPerTick = 16; |
| |
| DEFINE_FLAG(bool, trace_profiled_isolates, false, "Trace profiled isolates."); |
| |
| DEFINE_FLAG(int, |
| profile_period, |
| 1000, |
| "Time between profiler samples in microseconds. Minimum 50."); |
| DEFINE_FLAG(int, |
| max_profile_depth, |
| kSampleSize* kMaxSamplesPerTick, |
| "Maximum number stack frames walked. Minimum 1. Maximum 255."); |
| #if defined(USING_SIMULATOR) |
| DEFINE_FLAG(bool, profile_vm, true, "Always collect native stack traces."); |
| #else |
| DEFINE_FLAG(bool, profile_vm, false, "Always collect native stack traces."); |
| #endif |
| DEFINE_FLAG(bool, |
| profile_vm_allocation, |
| false, |
| "Collect native stack traces when tracing Dart allocations."); |
| |
| DEFINE_FLAG( |
| int, |
| sample_buffer_duration, |
| 0, |
| "Defines the size of the profiler sample buffer to contain at least " |
| "N seconds of samples at a given sample rate. If not provided, the " |
| "default is ~4 seconds. Large values will greatly increase memory " |
| "consumption."); |
| |
| #ifndef PRODUCT |
| |
| RelaxedAtomic<bool> Profiler::initialized_ = false; |
| SampleBuffer* Profiler::sample_buffer_ = NULL; |
| AllocationSampleBuffer* Profiler::allocation_sample_buffer_ = NULL; |
| ProfilerCounters Profiler::counters_ = {}; |
| |
| void Profiler::Init() { |
| // Place some sane restrictions on user controlled flags. |
| SetSampleDepth(FLAG_max_profile_depth); |
| Sample::Init(); |
| if (!FLAG_profiler) { |
| return; |
| } |
| ASSERT(!initialized_); |
| SetSamplePeriod(FLAG_profile_period); |
| // The profiler may have been shutdown previously, in which case the sample |
| // buffer will have already been initialized. |
| if (sample_buffer_ == NULL) { |
| intptr_t capacity = CalculateSampleBufferCapacity(); |
| sample_buffer_ = new SampleBuffer(capacity); |
| Profiler::InitAllocationSampleBuffer(); |
| } |
| ThreadInterrupter::Init(); |
| ThreadInterrupter::Startup(); |
| initialized_ = true; |
| } |
| |
| void Profiler::InitAllocationSampleBuffer() { |
| ASSERT(Profiler::allocation_sample_buffer_ == NULL); |
| if (FLAG_profiler_native_memory) { |
| Profiler::allocation_sample_buffer_ = new AllocationSampleBuffer(); |
| } |
| } |
| |
| void Profiler::Cleanup() { |
| if (!FLAG_profiler) { |
| return; |
| } |
| ASSERT(initialized_); |
| ThreadInterrupter::Cleanup(); |
| delete sample_buffer_; |
| sample_buffer_ = NULL; |
| initialized_ = false; |
| } |
| |
| void Profiler::UpdateRunningState() { |
| if (!FLAG_profiler && initialized_) { |
| Cleanup(); |
| } else if (FLAG_profiler && !initialized_) { |
| Init(); |
| } |
| } |
| |
| void Profiler::SetSampleDepth(intptr_t depth) { |
| const int kMinimumDepth = 2; |
| const int kMaximumDepth = 255; |
| if (depth < kMinimumDepth) { |
| FLAG_max_profile_depth = kMinimumDepth; |
| } else if (depth > kMaximumDepth) { |
| FLAG_max_profile_depth = kMaximumDepth; |
| } else { |
| FLAG_max_profile_depth = depth; |
| } |
| } |
| |
| static intptr_t SamplesPerSecond() { |
| const intptr_t kMicrosPerSec = 1000000; |
| return kMicrosPerSec / FLAG_profile_period; |
| } |
| |
| intptr_t Profiler::CalculateSampleBufferCapacity() { |
| if (FLAG_sample_buffer_duration <= 0) { |
| return SampleBuffer::kDefaultBufferCapacity; |
| } |
| // Deeper stacks require more than a single Sample object to be represented |
| // correctly. These samples are chained, so we need to determine the worst |
| // case sample chain length for a single stack. |
| const intptr_t max_sample_chain_length = |
| FLAG_max_profile_depth / kMaxSamplesPerTick; |
| const intptr_t buffer_size = FLAG_sample_buffer_duration * |
| SamplesPerSecond() * max_sample_chain_length; |
| return buffer_size; |
| } |
| |
| void Profiler::SetSamplePeriod(intptr_t period) { |
| const int kMinimumProfilePeriod = 50; |
| if (period < kMinimumProfilePeriod) { |
| FLAG_profile_period = kMinimumProfilePeriod; |
| } else { |
| FLAG_profile_period = period; |
| } |
| ThreadInterrupter::SetInterruptPeriod(FLAG_profile_period); |
| } |
| |
| void Profiler::UpdateSamplePeriod() { |
| SetSamplePeriod(FLAG_profile_period); |
| } |
| |
| intptr_t Sample::pcs_length_ = 0; |
| intptr_t Sample::instance_size_ = 0; |
| |
| void Sample::Init() { |
| pcs_length_ = kSampleSize; |
| instance_size_ = sizeof(Sample) + (sizeof(uword) * pcs_length_); // NOLINT. |
| } |
| |
| uword* Sample::GetPCArray() const { |
| return reinterpret_cast<uword*>(reinterpret_cast<uintptr_t>(this) + |
| sizeof(*this)); |
| } |
| |
| SampleBuffer::SampleBuffer(intptr_t capacity) { |
| ASSERT(Sample::instance_size() > 0); |
| |
| const intptr_t size = Utils::RoundUp(capacity * Sample::instance_size(), |
| VirtualMemory::PageSize()); |
| const bool kNotExecutable = false; |
| memory_ = VirtualMemory::Allocate(size, kNotExecutable, "dart-profiler"); |
| if (memory_ == NULL) { |
| OUT_OF_MEMORY(); |
| } |
| |
| samples_ = reinterpret_cast<Sample*>(memory_->address()); |
| capacity_ = capacity; |
| cursor_ = 0; |
| |
| if (FLAG_trace_profiler) { |
| OS::PrintErr("Profiler holds %" Pd " samples\n", capacity); |
| OS::PrintErr("Profiler sample is %" Pd " bytes\n", Sample::instance_size()); |
| OS::PrintErr("Profiler memory usage = %" Pd " bytes\n", size); |
| } |
| if (FLAG_sample_buffer_duration != 0) { |
| OS::PrintErr( |
| "** WARNING ** Custom sample buffer size provided via " |
| "--sample-buffer-duration\n"); |
| OS::PrintErr( |
| "The sample buffer can hold at least %ds worth of " |
| "samples with stacks depths of up to %d, collected at " |
| "a sample rate of %" Pd "Hz.\n", |
| FLAG_sample_buffer_duration, FLAG_max_profile_depth, |
| SamplesPerSecond()); |
| OS::PrintErr("The resulting sample buffer size is %" Pd " bytes.\n", size); |
| } |
| } |
| |
| AllocationSampleBuffer::AllocationSampleBuffer(intptr_t capacity) |
| : SampleBuffer(capacity), mutex_(), free_sample_list_(NULL) {} |
| |
| SampleBuffer::~SampleBuffer() { |
| delete memory_; |
| } |
| |
| AllocationSampleBuffer::~AllocationSampleBuffer() { |
| } |
| |
| Sample* SampleBuffer::At(intptr_t idx) const { |
| ASSERT(idx >= 0); |
| ASSERT(idx < capacity_); |
| intptr_t offset = idx * Sample::instance_size(); |
| uint8_t* samples = reinterpret_cast<uint8_t*>(samples_); |
| return reinterpret_cast<Sample*>(samples + offset); |
| } |
| |
| intptr_t SampleBuffer::ReserveSampleSlot() { |
| ASSERT(samples_ != NULL); |
| uintptr_t cursor = cursor_.fetch_add(1u); |
| // Map back into sample buffer range. |
| cursor = cursor % capacity_; |
| return cursor; |
| } |
| |
| Sample* SampleBuffer::ReserveSample() { |
| return At(ReserveSampleSlot()); |
| } |
| |
| Sample* SampleBuffer::ReserveSampleAndLink(Sample* previous) { |
| ASSERT(previous != NULL); |
| intptr_t next_index = ReserveSampleSlot(); |
| Sample* next = At(next_index); |
| next->Init(previous->port(), previous->timestamp(), previous->tid()); |
| next->set_head_sample(false); |
| // Mark that previous continues at next. |
| previous->SetContinuationIndex(next_index); |
| return next; |
| } |
| |
| void AllocationSampleBuffer::FreeAllocationSample(Sample* sample) { |
| MutexLocker ml(&mutex_); |
| while (sample != NULL) { |
| intptr_t continuation_index = -1; |
| if (sample->is_continuation_sample()) { |
| continuation_index = sample->continuation_index(); |
| } |
| sample->Clear(); |
| sample->set_next_free(free_sample_list_); |
| free_sample_list_ = sample; |
| |
| if (continuation_index != -1) { |
| sample = At(continuation_index); |
| } else { |
| sample = NULL; |
| } |
| } |
| } |
| |
| intptr_t AllocationSampleBuffer::ReserveSampleSlotLocked() { |
| if (free_sample_list_ != NULL) { |
| Sample* free_sample = free_sample_list_; |
| free_sample_list_ = free_sample->next_free(); |
| free_sample->set_next_free(NULL); |
| uint8_t* samples_array_ptr = reinterpret_cast<uint8_t*>(samples_); |
| uint8_t* free_sample_ptr = reinterpret_cast<uint8_t*>(free_sample); |
| return static_cast<intptr_t>((free_sample_ptr - samples_array_ptr) / |
| Sample::instance_size()); |
| } else if (cursor_ < static_cast<uintptr_t>(capacity_ - 1)) { |
| return cursor_ += 1; |
| } else { |
| return -1; |
| } |
| } |
| |
| Sample* AllocationSampleBuffer::ReserveSampleAndLink(Sample* previous) { |
| MutexLocker ml(&mutex_); |
| ASSERT(previous != NULL); |
| intptr_t next_index = ReserveSampleSlotLocked(); |
| if (next_index < 0) { |
| // Could not find a free sample. |
| return NULL; |
| } |
| Sample* next = At(next_index); |
| next->Init(previous->port(), previous->timestamp(), previous->tid()); |
| next->set_native_allocation_address(previous->native_allocation_address()); |
| next->set_native_allocation_size_bytes( |
| previous->native_allocation_size_bytes()); |
| next->set_head_sample(false); |
| // Mark that previous continues at next. |
| previous->SetContinuationIndex(next_index); |
| return next; |
| } |
| |
| Sample* AllocationSampleBuffer::ReserveSample() { |
| MutexLocker ml(&mutex_); |
| intptr_t index = ReserveSampleSlotLocked(); |
| if (index < 0) { |
| return NULL; |
| } |
| return At(index); |
| } |
| |
| // Attempts to find the true return address when a Dart frame is being setup |
| // or torn down. |
| // NOTE: Architecture specific implementations below. |
| class ReturnAddressLocator : public ValueObject { |
| public: |
| ReturnAddressLocator(Sample* sample, const Code& code) |
| : stack_buffer_(sample->GetStackBuffer()), |
| pc_(sample->pc()), |
| code_(Code::ZoneHandle(code.raw())) { |
| ASSERT(!code_.IsNull()); |
| ASSERT(code_.ContainsInstructionAt(pc())); |
| } |
| |
| ReturnAddressLocator(uword pc, uword* stack_buffer, const Code& code) |
| : stack_buffer_(stack_buffer), |
| pc_(pc), |
| code_(Code::ZoneHandle(code.raw())) { |
| ASSERT(!code_.IsNull()); |
| ASSERT(code_.ContainsInstructionAt(pc_)); |
| } |
| |
| uword pc() { return pc_; } |
| |
| // Returns false on failure. |
| bool LocateReturnAddress(uword* return_address); |
| |
| // Returns offset into code object. |
| intptr_t RelativePC() { |
| ASSERT(pc() >= code_.PayloadStart()); |
| return static_cast<intptr_t>(pc() - code_.PayloadStart()); |
| } |
| |
| uint8_t* CodePointer(intptr_t offset) { |
| const intptr_t size = code_.Size(); |
| ASSERT(offset < size); |
| uint8_t* code_pointer = reinterpret_cast<uint8_t*>(code_.PayloadStart()); |
| code_pointer += offset; |
| return code_pointer; |
| } |
| |
| uword StackAt(intptr_t i) { |
| ASSERT(i >= 0); |
| ASSERT(i < Sample::kStackBufferSizeInWords); |
| return stack_buffer_[i]; |
| } |
| |
| private: |
| uword* stack_buffer_; |
| uword pc_; |
| const Code& code_; |
| }; |
| |
| #if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64) |
| bool ReturnAddressLocator::LocateReturnAddress(uword* return_address) { |
| ASSERT(return_address != NULL); |
| const intptr_t offset = RelativePC(); |
| ASSERT(offset >= 0); |
| const intptr_t size = code_.Size(); |
| ASSERT(offset < size); |
| const intptr_t prologue_offset = code_.GetPrologueOffset(); |
| if (offset < prologue_offset) { |
| // Before the prologue, return address is at the top of the stack. |
| // TODO(johnmccutchan): Some intrinsics and stubs do not conform to the |
| // expected stack layout. Use a more robust solution for those code objects. |
| *return_address = StackAt(0); |
| return true; |
| } |
| // Detect if we are: |
| // push ebp <--- here |
| // mov ebp, esp |
| // on X64 the register names are different but the sequence is the same. |
| ProloguePattern pp(pc()); |
| if (pp.IsValid()) { |
| // Stack layout: |
| // 0 RETURN ADDRESS. |
| *return_address = StackAt(0); |
| return true; |
| } |
| // Detect if we are: |
| // push ebp |
| // mov ebp, esp <--- here |
| // on X64 the register names are different but the sequence is the same. |
| SetFramePointerPattern sfpp(pc()); |
| if (sfpp.IsValid()) { |
| // Stack layout: |
| // 0 CALLER FRAME POINTER |
| // 1 RETURN ADDRESS |
| *return_address = StackAt(1); |
| return true; |
| } |
| // Detect if we are: |
| // ret <--- here |
| ReturnPattern rp(pc()); |
| if (rp.IsValid()) { |
| // Stack layout: |
| // 0 RETURN ADDRESS. |
| *return_address = StackAt(0); |
| return true; |
| } |
| return false; |
| } |
| #elif defined(TARGET_ARCH_ARM) |
| bool ReturnAddressLocator::LocateReturnAddress(uword* return_address) { |
| ASSERT(return_address != NULL); |
| return false; |
| } |
| #elif defined(TARGET_ARCH_ARM64) |
| bool ReturnAddressLocator::LocateReturnAddress(uword* return_address) { |
| ASSERT(return_address != NULL); |
| return false; |
| } |
| #else |
| #error ReturnAddressLocator implementation missing for this architecture. |
| #endif |
| |
| bool SampleFilter::TimeFilterSample(Sample* sample) { |
| if ((time_origin_micros_ == -1) || (time_extent_micros_ == -1)) { |
| // No time filter passed in, always pass. |
| return true; |
| } |
| const int64_t timestamp = sample->timestamp(); |
| int64_t delta = timestamp - time_origin_micros_; |
| return (delta >= 0) && (delta <= time_extent_micros_); |
| } |
| |
| bool SampleFilter::TaskFilterSample(Sample* sample) { |
| const intptr_t task = static_cast<intptr_t>(sample->thread_task()); |
| if (thread_task_mask_ == kNoTaskFilter) { |
| return true; |
| } |
| return (task & thread_task_mask_) != 0; |
| } |
| |
| ClearProfileVisitor::ClearProfileVisitor(Isolate* isolate) |
| : SampleVisitor(isolate->main_port()) {} |
| |
| void ClearProfileVisitor::VisitSample(Sample* sample) { |
| sample->Clear(); |
| } |
| |
| static void DumpStackFrame(intptr_t frame_index, uword pc, uword fp) { |
| uword start = 0; |
| if (auto const name = NativeSymbolResolver::LookupSymbolName(pc, &start)) { |
| uword offset = pc - start; |
| OS::PrintErr(" pc 0x%" Pp " fp 0x%" Pp " %s+0x%" Px "\n", pc, fp, name, |
| offset); |
| NativeSymbolResolver::FreeSymbolName(name); |
| return; |
| } |
| |
| char* dso_name; |
| uword dso_base; |
| if (NativeSymbolResolver::LookupSharedObject(pc, &dso_base, &dso_name)) { |
| uword dso_offset = pc - dso_base; |
| OS::PrintErr(" pc 0x%" Pp " fp 0x%" Pp " %s+0x%" Px "\n", pc, fp, dso_name, |
| dso_offset); |
| NativeSymbolResolver::FreeSymbolName(dso_name); |
| return; |
| } |
| |
| OS::PrintErr(" pc 0x%" Pp " fp 0x%" Pp " Unknown symbol\n", pc, fp); |
| } |
| |
| class ProfilerStackWalker : public ValueObject { |
| public: |
| ProfilerStackWalker(Dart_Port port_id, |
| Sample* head_sample, |
| SampleBuffer* sample_buffer, |
| intptr_t skip_count = 0) |
| : port_id_(port_id), |
| sample_(head_sample), |
| sample_buffer_(sample_buffer), |
| skip_count_(skip_count), |
| frames_skipped_(0), |
| frame_index_(0), |
| total_frames_(0) { |
| if (sample_ == NULL) { |
| ASSERT(sample_buffer_ == NULL); |
| } else { |
| ASSERT(sample_buffer_ != NULL); |
| ASSERT(sample_->head_sample()); |
| } |
| } |
| |
| bool Append(uword pc, uword fp) { |
| if (frames_skipped_ < skip_count_) { |
| frames_skipped_++; |
| return true; |
| } |
| |
| if (sample_ == NULL) { |
| DumpStackFrame(frame_index_, pc, fp); |
| frame_index_++; |
| total_frames_++; |
| return true; |
| } |
| if (total_frames_ >= FLAG_max_profile_depth) { |
| sample_->set_truncated_trace(true); |
| return false; |
| } |
| ASSERT(sample_ != NULL); |
| if (frame_index_ == kSampleSize) { |
| Sample* new_sample = sample_buffer_->ReserveSampleAndLink(sample_); |
| if (new_sample == NULL) { |
| // Could not reserve new sample- mark this as truncated. |
| sample_->set_truncated_trace(true); |
| return false; |
| } |
| frame_index_ = 0; |
| sample_ = new_sample; |
| } |
| ASSERT(frame_index_ < kSampleSize); |
| sample_->SetAt(frame_index_, pc); |
| frame_index_++; |
| total_frames_++; |
| return true; |
| } |
| |
| protected: |
| Dart_Port port_id_; |
| Sample* sample_; |
| SampleBuffer* sample_buffer_; |
| intptr_t skip_count_; |
| intptr_t frames_skipped_; |
| intptr_t frame_index_; |
| intptr_t total_frames_; |
| }; |
| |
| // Executing Dart code, walk the stack. |
| class ProfilerDartStackWalker : public ProfilerStackWalker { |
| public: |
| ProfilerDartStackWalker(Thread* thread, |
| Sample* sample, |
| SampleBuffer* sample_buffer, |
| uword pc, |
| uword fp, |
| bool allocation_sample, |
| intptr_t skip_count = 0) |
| : ProfilerStackWalker((thread->isolate() != NULL) |
| ? thread->isolate()->main_port() |
| : ILLEGAL_PORT, |
| sample, |
| sample_buffer, |
| skip_count), |
| thread_(thread), |
| pc_(reinterpret_cast<uword*>(pc)), |
| fp_(reinterpret_cast<uword*>(fp)) {} |
| |
| bool IsInterpretedFrame(uword* fp) { |
| #if defined(DART_PRECOMPILED_RUNTIME) |
| return false; |
| #else |
| Interpreter* interpreter = thread_->interpreter(); |
| if (interpreter == nullptr) return false; |
| return interpreter->HasFrame(reinterpret_cast<uword>(fp)); |
| #endif |
| } |
| |
| void walk() { |
| RELEASE_ASSERT(StubCode::HasBeenInitialized()); |
| if (thread_->isolate()->IsDeoptimizing()) { |
| sample_->set_ignore_sample(true); |
| return; |
| } |
| |
| uword* exit_fp = reinterpret_cast<uword*>(thread_->top_exit_frame_info()); |
| bool in_interpreted_frame; |
| bool has_exit_frame = exit_fp != 0; |
| if (has_exit_frame) { |
| if (IsInterpretedFrame(exit_fp)) { |
| // Exited from interpreter. |
| pc_ = 0; |
| fp_ = exit_fp; |
| in_interpreted_frame = true; |
| RELEASE_ASSERT(IsInterpretedFrame(fp_)); |
| } else { |
| // Exited from compiled code. |
| pc_ = 0; |
| fp_ = exit_fp; |
| in_interpreted_frame = false; |
| } |
| |
| // Skip exit frame. |
| pc_ = CallerPC(in_interpreted_frame); |
| fp_ = CallerFP(in_interpreted_frame); |
| |
| // Can only move between interpreted and compiled frames after an exit |
| // frame. |
| RELEASE_ASSERT(IsInterpretedFrame(fp_) == in_interpreted_frame); |
| } else { |
| if (thread_->vm_tag() == VMTag::kDartCompiledTagId) { |
| // Running compiled code. |
| // Use the FP and PC from the thread interrupt or simulator; already set |
| // in the constructor. |
| in_interpreted_frame = false; |
| } else if (thread_->vm_tag() == VMTag::kDartInterpretedTagId) { |
| // Running interpreter. |
| #if defined(DART_PRECOMPILED_RUNTIME) |
| UNREACHABLE(); |
| #else |
| pc_ = reinterpret_cast<uword*>(thread_->interpreter()->get_pc()); |
| fp_ = reinterpret_cast<uword*>(thread_->interpreter()->get_fp()); |
| #endif |
| in_interpreted_frame = true; |
| RELEASE_ASSERT(IsInterpretedFrame(fp_)); |
| } else { |
| // No Dart on the stack; caller shouldn't use this walker. |
| UNREACHABLE(); |
| } |
| } |
| |
| sample_->set_exit_frame_sample(has_exit_frame); |
| |
| if (!has_exit_frame && !in_interpreted_frame && |
| (CallerPC(in_interpreted_frame) == EntryMarker(in_interpreted_frame))) { |
| // During the prologue of a function, CallerPC will return the caller's |
| // caller. For most frames, the missing PC will be added during profile |
| // processing. However, during this stack walk, it can cause us to fail |
| // to identify the entry frame and lead the stack walk into the weeds. |
| // Do not continue the stalk walk since this might be a false positive |
| // from a Smi or unboxed value. |
| RELEASE_ASSERT(!has_exit_frame); |
| sample_->set_ignore_sample(true); |
| return; |
| } |
| |
| for (;;) { |
| // Skip entry frame. |
| if (StubCode::InInvocationStub(reinterpret_cast<uword>(pc_), |
| in_interpreted_frame)) { |
| pc_ = 0; |
| fp_ = ExitLink(in_interpreted_frame); |
| if (fp_ == 0) { |
| break; // End of Dart stack. |
| } |
| in_interpreted_frame = IsInterpretedFrame(fp_); |
| |
| // Skip exit frame. |
| pc_ = CallerPC(in_interpreted_frame); |
| fp_ = CallerFP(in_interpreted_frame); |
| |
| // At least one frame between exit and next entry frame. |
| RELEASE_ASSERT(!StubCode::InInvocationStub(reinterpret_cast<uword>(pc_), |
| in_interpreted_frame)); |
| } |
| |
| if (!Append(reinterpret_cast<uword>(pc_), reinterpret_cast<uword>(fp_))) { |
| break; // Sample is full. |
| } |
| |
| pc_ = CallerPC(in_interpreted_frame); |
| fp_ = CallerFP(in_interpreted_frame); |
| |
| // Can only move between interpreted and compiled frames after an exit |
| // frame. |
| RELEASE_ASSERT(IsInterpretedFrame(fp_) == in_interpreted_frame); |
| } |
| } |
| |
| private: |
| uword* CallerPC(bool interp) const { |
| ASSERT(fp_ != NULL); |
| uword* caller_pc_ptr = |
| fp_ + (interp ? kKBCSavedCallerPcSlotFromFp : kSavedCallerPcSlotFromFp); |
| // MSan/ASan are unaware of frames initialized by generated code. |
| MSAN_UNPOISON(caller_pc_ptr, kWordSize); |
| ASAN_UNPOISON(caller_pc_ptr, kWordSize); |
| return reinterpret_cast<uword*>(*caller_pc_ptr); |
| } |
| |
| uword* CallerFP(bool interp) const { |
| ASSERT(fp_ != NULL); |
| uword* caller_fp_ptr = |
| fp_ + (interp ? kKBCSavedCallerFpSlotFromFp : kSavedCallerFpSlotFromFp); |
| // MSan/ASan are unaware of frames initialized by generated code. |
| MSAN_UNPOISON(caller_fp_ptr, kWordSize); |
| ASAN_UNPOISON(caller_fp_ptr, kWordSize); |
| return reinterpret_cast<uword*>(*caller_fp_ptr); |
| } |
| |
| uword* ExitLink(bool interp) const { |
| ASSERT(fp_ != NULL); |
| uword* exit_link_ptr = |
| fp_ + (interp ? kKBCExitLinkSlotFromEntryFp : kExitLinkSlotFromEntryFp); |
| // MSan/ASan are unaware of frames initialized by generated code. |
| MSAN_UNPOISON(exit_link_ptr, kWordSize); |
| ASAN_UNPOISON(exit_link_ptr, kWordSize); |
| return reinterpret_cast<uword*>(*exit_link_ptr); |
| } |
| |
| // Note because of stack guards, it is important that this marker lives |
| // above FP. |
| uword* EntryMarker(bool interp) const { |
| ASSERT(!interp); |
| ASSERT(fp_ != NULL); |
| uword* entry_marker_ptr = fp_ + kSavedCallerPcSlotFromFp + 1; |
| // MSan/ASan are unaware of frames initialized by generated code. |
| MSAN_UNPOISON(entry_marker_ptr, kWordSize); |
| ASAN_UNPOISON(entry_marker_ptr, kWordSize); |
| return reinterpret_cast<uword*>(*entry_marker_ptr); |
| } |
| |
| Thread* const thread_; |
| uword* pc_; |
| uword* fp_; |
| }; |
| |
| // If the VM is compiled without frame pointers (which is the default on |
| // recent GCC versions with optimizing enabled) the stack walking code may |
| // fail. |
| // |
| class ProfilerNativeStackWalker : public ProfilerStackWalker { |
| public: |
| ProfilerNativeStackWalker(ProfilerCounters* counters, |
| Dart_Port port_id, |
| Sample* sample, |
| SampleBuffer* sample_buffer, |
| uword stack_lower, |
| uword stack_upper, |
| uword pc, |
| uword fp, |
| uword sp, |
| intptr_t skip_count = 0) |
| : ProfilerStackWalker(port_id, sample, sample_buffer, skip_count), |
| counters_(counters), |
| stack_upper_(stack_upper), |
| original_pc_(pc), |
| original_fp_(fp), |
| original_sp_(sp), |
| lower_bound_(stack_lower) {} |
| |
| void walk() { |
| const uword kMaxStep = VirtualMemory::PageSize(); |
| |
| Append(original_pc_, original_fp_); |
| |
| uword* pc = reinterpret_cast<uword*>(original_pc_); |
| uword* fp = reinterpret_cast<uword*>(original_fp_); |
| uword* previous_fp = fp; |
| |
| uword gap = original_fp_ - original_sp_; |
| if (gap >= kMaxStep) { |
| // Gap between frame pointer and stack pointer is |
| // too large. |
| counters_->incomplete_sample_fp_step.fetch_add(1); |
| return; |
| } |
| |
| if (!ValidFramePointer(fp)) { |
| counters_->incomplete_sample_fp_bounds.fetch_add(1); |
| return; |
| } |
| |
| while (true) { |
| pc = CallerPC(fp); |
| previous_fp = fp; |
| fp = CallerFP(fp); |
| |
| if (fp == NULL) { |
| return; |
| } |
| |
| if (fp <= previous_fp) { |
| // Frame pointer did not move to a higher address. |
| counters_->incomplete_sample_fp_step.fetch_add(1); |
| return; |
| } |
| |
| gap = fp - previous_fp; |
| if (gap >= kMaxStep) { |
| // Frame pointer step is too large. |
| counters_->incomplete_sample_fp_step.fetch_add(1); |
| return; |
| } |
| |
| if (!ValidFramePointer(fp)) { |
| // Frame pointer is outside of isolate stack boundary. |
| counters_->incomplete_sample_fp_bounds.fetch_add(1); |
| return; |
| } |
| |
| const uword pc_value = reinterpret_cast<uword>(pc); |
| if ((pc_value + 1) < pc_value) { |
| // It is not uncommon to encounter an invalid pc as we |
| // traverse a stack frame. Most of these we can tolerate. If |
| // the pc is so large that adding one to it will cause an |
| // overflow it is invalid and it will cause headaches later |
| // while we are building the profile. Discard it. |
| counters_->incomplete_sample_bad_pc.fetch_add(1); |
| return; |
| } |
| |
| // Move the lower bound up. |
| lower_bound_ = reinterpret_cast<uword>(fp); |
| |
| if (!Append(pc_value, reinterpret_cast<uword>(fp))) { |
| return; |
| } |
| } |
| } |
| |
| private: |
| uword* CallerPC(uword* fp) const { |
| ASSERT(fp != NULL); |
| uword* caller_pc_ptr = fp + kSavedCallerPcSlotFromFp; |
| // This may actually be uninitialized, by design (see class comment above). |
| MSAN_UNPOISON(caller_pc_ptr, kWordSize); |
| ASAN_UNPOISON(caller_pc_ptr, kWordSize); |
| return reinterpret_cast<uword*>(*caller_pc_ptr); |
| } |
| |
| uword* CallerFP(uword* fp) const { |
| ASSERT(fp != NULL); |
| uword* caller_fp_ptr = fp + kSavedCallerFpSlotFromFp; |
| // This may actually be uninitialized, by design (see class comment above). |
| MSAN_UNPOISON(caller_fp_ptr, kWordSize); |
| ASAN_UNPOISON(caller_fp_ptr, kWordSize); |
| return reinterpret_cast<uword*>(*caller_fp_ptr); |
| } |
| |
| bool ValidFramePointer(uword* fp) const { |
| if (fp == NULL) { |
| return false; |
| } |
| uword cursor = reinterpret_cast<uword>(fp); |
| cursor += sizeof(fp); |
| bool r = (cursor >= lower_bound_) && (cursor < stack_upper_); |
| return r; |
| } |
| |
| ProfilerCounters* const counters_; |
| const uword stack_upper_; |
| const uword original_pc_; |
| const uword original_fp_; |
| const uword original_sp_; |
| uword lower_bound_; |
| }; |
| |
| static void CopyStackBuffer(Sample* sample, uword sp_addr) { |
| ASSERT(sample != NULL); |
| uword* sp = reinterpret_cast<uword*>(sp_addr); |
| uword* buffer = sample->GetStackBuffer(); |
| if (sp != NULL) { |
| for (intptr_t i = 0; i < Sample::kStackBufferSizeInWords; i++) { |
| MSAN_UNPOISON(sp, kWordSize); |
| ASAN_UNPOISON(sp, kWordSize); |
| buffer[i] = *sp; |
| sp++; |
| } |
| } |
| } |
| |
| #if defined(HOST_OS_WINDOWS) |
| // On Windows this code is synchronously executed from the thread interrupter |
| // thread. This means we can safely have a static fault_address. |
| static uword fault_address = 0; |
| static LONG GuardPageExceptionFilter(EXCEPTION_POINTERS* ep) { |
| fault_address = 0; |
| if (ep->ExceptionRecord->ExceptionCode != STATUS_GUARD_PAGE_VIOLATION) { |
| return EXCEPTION_CONTINUE_SEARCH; |
| } |
| // https://goo.gl/p5Fe10 |
| fault_address = ep->ExceptionRecord->ExceptionInformation[1]; |
| // Read access. |
| ASSERT(ep->ExceptionRecord->ExceptionInformation[0] == 0); |
| return EXCEPTION_EXECUTE_HANDLER; |
| } |
| #endif |
| |
| // All memory access done to collect the sample is performed in CollectSample. |
| static void CollectSample(Isolate* isolate, |
| bool exited_dart_code, |
| bool in_dart_code, |
| Sample* sample, |
| ProfilerNativeStackWalker* native_stack_walker, |
| ProfilerDartStackWalker* dart_stack_walker, |
| uword pc, |
| uword fp, |
| uword sp, |
| ProfilerCounters* counters) { |
| ASSERT(counters != NULL); |
| #if defined(HOST_OS_WINDOWS) |
| // Use structured exception handling to trap guard page access on Windows. |
| __try { |
| #endif |
| |
| if (in_dart_code) { |
| // We can only trust the stack pointer if we are executing Dart code. |
| // See http://dartbug.com/20421 for details. |
| CopyStackBuffer(sample, sp); |
| } |
| |
| if (FLAG_profile_vm) { |
| // Always walk the native stack collecting both native and Dart frames. |
| counters->stack_walker_native.fetch_add(1); |
| native_stack_walker->walk(); |
| } else if (StubCode::HasBeenInitialized() && exited_dart_code) { |
| counters->stack_walker_dart_exit.fetch_add(1); |
| // We have a valid exit frame info, use the Dart stack walker. |
| dart_stack_walker->walk(); |
| } else if (StubCode::HasBeenInitialized() && in_dart_code) { |
| counters->stack_walker_dart.fetch_add(1); |
| // We are executing Dart code. We have frame pointers. |
| dart_stack_walker->walk(); |
| } else { |
| counters->stack_walker_none.fetch_add(1); |
| sample->SetAt(0, pc); |
| } |
| |
| #if defined(HOST_OS_WINDOWS) |
| // Use structured exception handling to trap guard page access. |
| } __except (GuardPageExceptionFilter(GetExceptionInformation())) { // NOLINT |
| // Sample collection triggered a guard page fault: |
| // 1) discard entire sample. |
| sample->set_ignore_sample(true); |
| |
| // 2) Reenable guard bit on page that triggered the fault. |
| // https://goo.gl/5mCsXW |
| DWORD new_protect = PAGE_READWRITE | PAGE_GUARD; |
| DWORD old_protect = 0; |
| BOOL success = |
| VirtualProtect(reinterpret_cast<void*>(fault_address), |
| sizeof(fault_address), new_protect, &old_protect); |
| USE(success); |
| ASSERT(success); |
| ASSERT(old_protect == PAGE_READWRITE); |
| } |
| #endif |
| } |
| |
| static bool ValidateThreadStackBounds(uintptr_t fp, |
| uintptr_t sp, |
| uword stack_lower, |
| uword stack_upper) { |
| if (stack_lower >= stack_upper) { |
| // Stack boundary is invalid. |
| return false; |
| } |
| |
| if ((sp < stack_lower) || (sp >= stack_upper)) { |
| // Stack pointer is outside thread's stack boundary. |
| return false; |
| } |
| |
| if ((fp < stack_lower) || (fp >= stack_upper)) { |
| // Frame pointer is outside threads's stack boundary. |
| return false; |
| } |
| |
| return true; |
| } |
| |
| // Get |thread|'s stack boundary and verify that |sp| and |fp| are within |
| // it. Return |false| if anything looks suspicious. |
| static bool GetAndValidateThreadStackBounds(OSThread* os_thread, |
| Thread* thread, |
| uintptr_t fp, |
| uintptr_t sp, |
| uword* stack_lower, |
| uword* stack_upper) { |
| ASSERT(os_thread != NULL); |
| ASSERT(stack_lower != NULL); |
| ASSERT(stack_upper != NULL); |
| |
| #if defined(USING_SIMULATOR) |
| const bool use_simulator_stack_bounds = |
| thread != NULL && thread->IsExecutingDartCode(); |
| if (use_simulator_stack_bounds) { |
| Isolate* isolate = thread->isolate(); |
| ASSERT(isolate != NULL); |
| Simulator* simulator = isolate->simulator(); |
| *stack_lower = simulator->stack_limit(); |
| *stack_upper = simulator->stack_base(); |
| } |
| #else |
| const bool use_simulator_stack_bounds = false; |
| #endif // defined(USING_SIMULATOR) |
| |
| if (!use_simulator_stack_bounds) { |
| *stack_lower = os_thread->stack_limit(); |
| *stack_upper = os_thread->stack_base(); |
| } |
| |
| if ((*stack_lower == 0) || (*stack_upper == 0)) { |
| return false; |
| } |
| |
| if (!use_simulator_stack_bounds && (sp > *stack_lower)) { |
| // The stack pointer gives us a tighter lower bound. |
| *stack_lower = sp; |
| } |
| |
| return ValidateThreadStackBounds(fp, sp, *stack_lower, *stack_upper); |
| } |
| |
| // Some simple sanity checking of |pc|, |fp|, and |sp|. |
| static bool InitialRegisterCheck(uintptr_t pc, uintptr_t fp, uintptr_t sp) { |
| if ((sp == 0) || (fp == 0) || (pc == 0)) { |
| // None of these registers should be zero. |
| return false; |
| } |
| |
| if (sp > fp) { |
| // Assuming the stack grows down, we should never have a stack pointer above |
| // the frame pointer. |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static Sample* SetupSample(Thread* thread, |
| SampleBuffer* sample_buffer, |
| ThreadId tid) { |
| ASSERT(thread != NULL); |
| Isolate* isolate = thread->isolate(); |
| ASSERT(sample_buffer != NULL); |
| Sample* sample = sample_buffer->ReserveSample(); |
| sample->Init(isolate->main_port(), OS::GetCurrentMonotonicMicros(), tid); |
| uword vm_tag = thread->vm_tag(); |
| #if defined(USING_SIMULATOR) |
| // When running in the simulator, the runtime entry function address |
| // (stored as the vm tag) is the address of a redirect function. |
| // Attempt to find the real runtime entry function address and use that. |
| uword redirect_vm_tag = Simulator::FunctionForRedirect(vm_tag); |
| if (redirect_vm_tag != 0) { |
| vm_tag = redirect_vm_tag; |
| } |
| #endif |
| sample->set_vm_tag(vm_tag); |
| sample->set_user_tag(isolate->user_tag()); |
| sample->set_thread_task(thread->task_kind()); |
| return sample; |
| } |
| |
| static Sample* SetupSampleNative(SampleBuffer* sample_buffer, ThreadId tid) { |
| Sample* sample = sample_buffer->ReserveSample(); |
| if (sample == NULL) { |
| return NULL; |
| } |
| sample->Init(ILLEGAL_PORT, OS::GetCurrentMonotonicMicros(), tid); |
| Thread* thread = Thread::Current(); |
| |
| // Note: setting thread task in order to be consistent with other samples. The |
| // task kind is not used by NativeAllocationSampleFilter for filtering |
| // purposes as some samples may be collected when no thread exists. |
| if (thread != NULL) { |
| sample->set_thread_task(thread->task_kind()); |
| sample->set_vm_tag(thread->vm_tag()); |
| } else { |
| sample->set_vm_tag(VMTag::kEmbedderTagId); |
| } |
| return sample; |
| } |
| |
| static bool CheckIsolate(Isolate* isolate) { |
| if ((isolate == NULL) || (Dart::vm_isolate() == NULL)) { |
| // No isolate. |
| return false; |
| } |
| return isolate != Dart::vm_isolate(); |
| } |
| |
| void Profiler::DumpStackTrace(void* context) { |
| if (context == NULL) { |
| DumpStackTrace(/*for_crash=*/true); |
| return; |
| } |
| #if defined(HOST_OS_LINUX) || defined(HOST_OS_MACOS) || defined(HOST_OS_ANDROID) |
| ucontext_t* ucontext = reinterpret_cast<ucontext_t*>(context); |
| mcontext_t mcontext = ucontext->uc_mcontext; |
| uword pc = SignalHandler::GetProgramCounter(mcontext); |
| uword fp = SignalHandler::GetFramePointer(mcontext); |
| uword sp = SignalHandler::GetCStackPointer(mcontext); |
| DumpStackTrace(sp, fp, pc, /*for_crash=*/true); |
| #elif defined(HOST_OS_WINDOWS) |
| CONTEXT* ctx = reinterpret_cast<CONTEXT*>(context); |
| #if defined(HOST_ARCH_IA32) |
| uword pc = static_cast<uword>(ctx->Eip); |
| uword fp = static_cast<uword>(ctx->Ebp); |
| uword sp = static_cast<uword>(ctx->Esp); |
| #elif defined(HOST_ARCH_X64) |
| uword pc = static_cast<uword>(ctx->Rip); |
| uword fp = static_cast<uword>(ctx->Rbp); |
| uword sp = static_cast<uword>(ctx->Rsp); |
| #else |
| #error Unsupported architecture. |
| #endif |
| DumpStackTrace(sp, fp, pc, /*for_crash=*/true); |
| #else |
| // TODO(fschneider): Add support for more platforms. |
| // Do nothing on unsupported platforms. |
| #endif |
| } |
| |
| void Profiler::DumpStackTrace(bool for_crash) { |
| uintptr_t sp = OSThread::GetCurrentStackPointer(); |
| uintptr_t fp = 0; |
| uintptr_t pc = OS::GetProgramCounter(); |
| |
| COPY_FP_REGISTER(fp); |
| |
| DumpStackTrace(sp, fp, pc, for_crash); |
| } |
| |
| void Profiler::DumpStackTrace(uword sp, uword fp, uword pc, bool for_crash) { |
| if (for_crash) { |
| // Allow only one stack trace to prevent recursively printing stack traces |
| // if we hit an assert while printing the stack. |
| static RelaxedAtomic<uintptr_t> started_dump = 0; |
| if (started_dump.fetch_add(1u) != 0) { |
| OS::PrintErr("Aborting re-entrant request for stack trace.\n"); |
| return; |
| } |
| } |
| |
| auto os_thread = OSThread::Current(); |
| ASSERT(os_thread != nullptr); |
| auto thread = Thread::Current(); // NULL if no current isolate. |
| auto isolate = thread == nullptr ? nullptr : thread->isolate(); |
| auto isolate_group = thread == nullptr ? nullptr : thread->isolate_group(); |
| auto source = isolate_group == nullptr ? nullptr : isolate_group->source(); |
| auto vm_source = |
| Dart::vm_isolate() == nullptr ? nullptr : Dart::vm_isolate()->source(); |
| const char* isolate_group_name = |
| isolate_group == nullptr ? "(nil)" : isolate_group->source()->name; |
| const char* isolate_name = isolate == nullptr ? "(nil)" : isolate->name(); |
| |
| OS::PrintErr("version=%s\n", Version::String()); |
| OS::PrintErr("pid=%" Pd ", thread=%" Pd |
| ", isolate_group=%s(%p), isolate=%s(%p)\n", |
| static_cast<intptr_t>(OS::ProcessId()), |
| OSThread::ThreadIdToIntPtr(os_thread->trace_id()), |
| isolate_group_name, isolate_group, isolate_name, isolate); |
| OS::PrintErr("isolate_instructions=%" Px ", vm_instructions=%" Px "\n", |
| source == nullptr |
| ? 0 |
| : reinterpret_cast<uword>(source->snapshot_instructions), |
| vm_source == nullptr |
| ? 0 |
| : reinterpret_cast<uword>(vm_source->snapshot_instructions)); |
| |
| if (!InitialRegisterCheck(pc, fp, sp)) { |
| OS::PrintErr("Stack dump aborted because InitialRegisterCheck failed.\n"); |
| return; |
| } |
| |
| uword stack_lower = 0; |
| uword stack_upper = 0; |
| if (!GetAndValidateThreadStackBounds(os_thread, thread, fp, sp, &stack_lower, |
| &stack_upper)) { |
| OS::PrintErr( |
| "Stack dump aborted because GetAndValidateThreadStackBounds failed.\n"); |
| return; |
| } |
| |
| ProfilerNativeStackWalker native_stack_walker(&counters_, ILLEGAL_PORT, NULL, |
| NULL, stack_lower, stack_upper, |
| pc, fp, sp, |
| /*skip_count=*/0); |
| native_stack_walker.walk(); |
| OS::PrintErr("-- End of DumpStackTrace\n"); |
| |
| if (thread != nullptr) { |
| if (thread->execution_state() == Thread::kThreadInNative) { |
| TransitionNativeToVM transition(thread); |
| StackFrame::DumpCurrentTrace(); |
| } else if (thread->execution_state() == Thread::kThreadInVM) { |
| StackFrame::DumpCurrentTrace(); |
| } |
| } |
| } |
| |
| void Profiler::SampleAllocation(Thread* thread, intptr_t cid) { |
| ASSERT(thread != NULL); |
| OSThread* os_thread = thread->os_thread(); |
| ASSERT(os_thread != NULL); |
| Isolate* isolate = thread->isolate(); |
| if (!CheckIsolate(isolate)) { |
| return; |
| } |
| |
| const bool exited_dart_code = thread->HasExitedDartCode(); |
| |
| SampleBuffer* sample_buffer = Profiler::sample_buffer(); |
| if (sample_buffer == NULL) { |
| // Profiler not initialized. |
| return; |
| } |
| |
| uintptr_t sp = OSThread::GetCurrentStackPointer(); |
| uintptr_t fp = 0; |
| uintptr_t pc = OS::GetProgramCounter(); |
| |
| COPY_FP_REGISTER(fp); |
| |
| uword stack_lower = 0; |
| uword stack_upper = 0; |
| |
| if (!InitialRegisterCheck(pc, fp, sp)) { |
| return; |
| } |
| |
| if (!GetAndValidateThreadStackBounds(os_thread, thread, fp, sp, &stack_lower, |
| &stack_upper)) { |
| // Could not get stack boundary. |
| return; |
| } |
| |
| Sample* sample = SetupSample(thread, sample_buffer, os_thread->trace_id()); |
| sample->SetAllocationCid(cid); |
| |
| if (FLAG_profile_vm_allocation) { |
| ProfilerNativeStackWalker native_stack_walker( |
| &counters_, (isolate != NULL) ? isolate->main_port() : ILLEGAL_PORT, |
| sample, sample_buffer, stack_lower, stack_upper, pc, fp, sp); |
| native_stack_walker.walk(); |
| } else if (exited_dart_code) { |
| ProfilerDartStackWalker dart_exit_stack_walker( |
| thread, sample, sample_buffer, pc, fp, /* allocation_sample*/ true); |
| dart_exit_stack_walker.walk(); |
| } else { |
| // Fall back. |
| uintptr_t pc = OS::GetProgramCounter(); |
| Sample* sample = SetupSample(thread, sample_buffer, os_thread->trace_id()); |
| sample->SetAllocationCid(cid); |
| sample->SetAt(0, pc); |
| } |
| } |
| |
| Sample* Profiler::SampleNativeAllocation(intptr_t skip_count, |
| uword address, |
| uintptr_t allocation_size) { |
| AllocationSampleBuffer* sample_buffer = Profiler::allocation_sample_buffer(); |
| if (sample_buffer == NULL) { |
| return NULL; |
| } |
| |
| uintptr_t sp = OSThread::GetCurrentStackPointer(); |
| uintptr_t fp = 0; |
| uintptr_t pc = OS::GetProgramCounter(); |
| |
| COPY_FP_REGISTER(fp); |
| |
| uword stack_lower = 0; |
| uword stack_upper = 0; |
| if (!InitialRegisterCheck(pc, fp, sp)) { |
| counters_.failure_native_allocation_sample.fetch_add(1); |
| return NULL; |
| } |
| |
| if (!(OSThread::GetCurrentStackBounds(&stack_lower, &stack_upper) && |
| ValidateThreadStackBounds(fp, sp, stack_lower, stack_upper))) { |
| // Could not get stack boundary. |
| counters_.failure_native_allocation_sample.fetch_add(1); |
| return NULL; |
| } |
| |
| OSThread* os_thread = OSThread::Current(); |
| Sample* sample = SetupSampleNative(sample_buffer, os_thread->trace_id()); |
| if (sample == NULL) { |
| OS::PrintErr( |
| "Native memory profile sample buffer is full because there are more " |
| "than %" Pd |
| " outstanding allocations. Not recording allocation " |
| "0x%" Px " with size: %" Pu " bytes.\n", |
| sample_buffer->capacity(), address, allocation_size); |
| return NULL; |
| } |
| |
| sample->set_native_allocation_address(address); |
| sample->set_native_allocation_size_bytes(allocation_size); |
| |
| ProfilerNativeStackWalker native_stack_walker( |
| &counters_, ILLEGAL_PORT, sample, sample_buffer, stack_lower, stack_upper, |
| pc, fp, sp, skip_count); |
| |
| native_stack_walker.walk(); |
| |
| return sample; |
| } |
| |
| void Profiler::SampleThreadSingleFrame(Thread* thread, uintptr_t pc) { |
| ASSERT(thread != NULL); |
| OSThread* os_thread = thread->os_thread(); |
| ASSERT(os_thread != NULL); |
| Isolate* isolate = thread->isolate(); |
| |
| SampleBuffer* sample_buffer = Profiler::sample_buffer(); |
| if (sample_buffer == NULL) { |
| // Profiler not initialized. |
| return; |
| } |
| |
| // Setup sample. |
| Sample* sample = SetupSample(thread, sample_buffer, os_thread->trace_id()); |
| // Increment counter for vm tag. |
| VMTagCounters* counters = isolate->vm_tag_counters(); |
| ASSERT(counters != NULL); |
| if (thread->IsMutatorThread()) { |
| counters->Increment(sample->vm_tag()); |
| } |
| |
| // Write the single pc value. |
| sample->SetAt(0, pc); |
| } |
| |
| void Profiler::SampleThread(Thread* thread, |
| const InterruptedThreadState& state) { |
| ASSERT(thread != NULL); |
| OSThread* os_thread = thread->os_thread(); |
| ASSERT(os_thread != NULL); |
| Isolate* isolate = thread->isolate(); |
| |
| // Thread is not doing VM work. |
| if (thread->task_kind() == Thread::kUnknownTask) { |
| counters_.bail_out_unknown_task.fetch_add(1); |
| return; |
| } |
| |
| if (StubCode::HasBeenInitialized() && StubCode::InJumpToFrameStub(state.pc)) { |
| // The JumpToFrame stub manually adjusts the stack pointer, frame |
| // pointer, and some isolate state. It is not safe to walk the |
| // stack when executing this stub. |
| counters_.bail_out_jump_to_exception_handler.fetch_add(1); |
| return; |
| } |
| |
| const bool in_dart_code = thread->IsExecutingDartCode(); |
| |
| uintptr_t sp = 0; |
| uintptr_t fp = state.fp; |
| uintptr_t pc = state.pc; |
| #if defined(USING_SIMULATOR) |
| Simulator* simulator = NULL; |
| #endif |
| |
| if (in_dart_code) { |
| // If we're in Dart code, use the Dart stack pointer. |
| #if defined(USING_SIMULATOR) |
| simulator = isolate->simulator(); |
| sp = simulator->get_register(SPREG); |
| fp = simulator->get_register(FPREG); |
| pc = simulator->get_pc(); |
| #else |
| sp = state.dsp; |
| #endif |
| } else { |
| // If we're in runtime code, use the C stack pointer. |
| sp = state.csp; |
| } |
| |
| if (!CheckIsolate(isolate)) { |
| counters_.bail_out_check_isolate.fetch_add(1); |
| return; |
| } |
| |
| if (thread->IsMutatorThread()) { |
| if (isolate->IsDeoptimizing()) { |
| counters_.single_frame_sample_deoptimizing.fetch_add(1); |
| SampleThreadSingleFrame(thread, pc); |
| return; |
| } |
| if (isolate->group()->compaction_in_progress()) { |
| // The Dart stack isn't fully walkable. |
| SampleThreadSingleFrame(thread, pc); |
| return; |
| } |
| } |
| |
| if (!InitialRegisterCheck(pc, fp, sp)) { |
| counters_.single_frame_sample_register_check.fetch_add(1); |
| SampleThreadSingleFrame(thread, pc); |
| return; |
| } |
| |
| uword stack_lower = 0; |
| uword stack_upper = 0; |
| if (!GetAndValidateThreadStackBounds(os_thread, thread, fp, sp, &stack_lower, |
| &stack_upper)) { |
| counters_.single_frame_sample_get_and_validate_stack_bounds.fetch_add(1); |
| // Could not get stack boundary. |
| SampleThreadSingleFrame(thread, pc); |
| return; |
| } |
| |
| // At this point we have a valid stack boundary for this isolate and |
| // know that our initial stack and frame pointers are within the boundary. |
| SampleBuffer* sample_buffer = Profiler::sample_buffer(); |
| if (sample_buffer == NULL) { |
| // Profiler not initialized. |
| return; |
| } |
| |
| // Setup sample. |
| Sample* sample = SetupSample(thread, sample_buffer, os_thread->trace_id()); |
| // Increment counter for vm tag. |
| VMTagCounters* counters = isolate->vm_tag_counters(); |
| ASSERT(counters != NULL); |
| if (thread->IsMutatorThread()) { |
| counters->Increment(sample->vm_tag()); |
| } |
| |
| ProfilerNativeStackWalker native_stack_walker( |
| &counters_, (isolate != NULL) ? isolate->main_port() : ILLEGAL_PORT, |
| sample, sample_buffer, stack_lower, stack_upper, pc, fp, sp); |
| const bool exited_dart_code = thread->HasExitedDartCode(); |
| ProfilerDartStackWalker dart_stack_walker(thread, sample, sample_buffer, pc, |
| fp, /* allocation_sample*/ false); |
| |
| // All memory access is done inside CollectSample. |
| CollectSample(isolate, exited_dart_code, in_dart_code, sample, |
| &native_stack_walker, &dart_stack_walker, pc, fp, sp, |
| &counters_); |
| } |
| |
| CodeDescriptor::CodeDescriptor(const AbstractCode code) : code_(code) {} |
| |
| uword CodeDescriptor::Start() const { |
| return code_.PayloadStart(); |
| } |
| |
| uword CodeDescriptor::Size() const { |
| return code_.Size(); |
| } |
| |
| int64_t CodeDescriptor::CompileTimestamp() const { |
| return code_.compile_timestamp(); |
| } |
| |
| CodeLookupTable::CodeLookupTable(Thread* thread) { |
| Build(thread); |
| } |
| |
| class CodeLookupTableBuilder : public ObjectVisitor { |
| public: |
| explicit CodeLookupTableBuilder(CodeLookupTable* table) : table_(table) { |
| ASSERT(table_ != NULL); |
| } |
| |
| ~CodeLookupTableBuilder() {} |
| |
| void VisitObject(ObjectPtr raw_obj) { |
| if (raw_obj->IsCode()) { |
| table_->Add(Code::Handle(Code::RawCast(raw_obj))); |
| } else if (raw_obj->IsBytecode()) { |
| table_->Add(Bytecode::Handle(Bytecode::RawCast(raw_obj))); |
| } |
| } |
| |
| private: |
| CodeLookupTable* table_; |
| }; |
| |
| void CodeLookupTable::Build(Thread* thread) { |
| ASSERT(thread != NULL); |
| Isolate* isolate = thread->isolate(); |
| ASSERT(isolate != NULL); |
| Isolate* vm_isolate = Dart::vm_isolate(); |
| ASSERT(vm_isolate != NULL); |
| |
| // Clear. |
| code_objects_.Clear(); |
| |
| // Add all found Code objects. |
| { |
| HeapIterationScope iteration(thread); |
| CodeLookupTableBuilder cltb(this); |
| iteration.IterateVMIsolateObjects(&cltb); |
| iteration.IterateOldObjects(&cltb); |
| } |
| |
| // Sort by entry. |
| code_objects_.Sort(CodeDescriptor::Compare); |
| |
| #if defined(DEBUG) |
| if (length() <= 1) { |
| return; |
| } |
| ASSERT(FindCode(0) == NULL); |
| ASSERT(FindCode(~0) == NULL); |
| // Sanity check that we don't have duplicate entries and that the entries |
| // are sorted. |
| for (intptr_t i = 0; i < length() - 1; i++) { |
| const CodeDescriptor* a = At(i); |
| const CodeDescriptor* b = At(i + 1); |
| ASSERT(a->Start() < b->Start()); |
| ASSERT(FindCode(a->Start()) == a); |
| ASSERT(FindCode(b->Start()) == b); |
| ASSERT(FindCode(a->Start() + a->Size() - 1) == a); |
| ASSERT(FindCode(b->Start() + b->Size() - 1) == b); |
| } |
| #endif |
| } |
| |
| void CodeLookupTable::Add(const Object& code) { |
| ASSERT(!code.IsNull()); |
| ASSERT(code.IsCode() || code.IsBytecode()); |
| CodeDescriptor* cd = new CodeDescriptor(AbstractCode(code.raw())); |
| code_objects_.Add(cd); |
| } |
| |
| const CodeDescriptor* CodeLookupTable::FindCode(uword pc) const { |
| intptr_t first = 0; |
| intptr_t count = length(); |
| while (count > 0) { |
| intptr_t current = first; |
| intptr_t step = count / 2; |
| current += step; |
| const CodeDescriptor* cd = At(current); |
| if (pc >= cd->Start()) { |
| first = ++current; |
| count -= step + 1; |
| } else { |
| count = step; |
| } |
| } |
| // First points to the first code object whose entry is greater than PC. |
| // That means the code object we need to check is first - 1. |
| if (first == 0) { |
| return NULL; |
| } |
| first--; |
| ASSERT(first >= 0); |
| ASSERT(first < length()); |
| const CodeDescriptor* cd = At(first); |
| if (cd->Contains(pc)) { |
| return cd; |
| } |
| return NULL; |
| } |
| |
| ProcessedSampleBuffer* SampleBuffer::BuildProcessedSampleBuffer( |
| SampleFilter* filter) { |
| ASSERT(filter != NULL); |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| |
| ProcessedSampleBuffer* buffer = new (zone) ProcessedSampleBuffer(); |
| |
| const intptr_t length = capacity(); |
| for (intptr_t i = 0; i < length; i++) { |
| Sample* sample = At(i); |
| if (sample->ignore_sample()) { |
| // Bad sample. |
| continue; |
| } |
| if (!sample->head_sample()) { |
| // An inner sample in a chain of samples. |
| continue; |
| } |
| // If we're requesting all the native allocation samples, we don't care |
| // whether or not we're in the same isolate as the sample. |
| if (sample->port() != filter->port()) { |
| // Another isolate. |
| continue; |
| } |
| if (sample->timestamp() == 0) { |
| // Empty. |
| continue; |
| } |
| if (sample->At(0) == 0) { |
| // No frames. |
| continue; |
| } |
| if (!filter->TimeFilterSample(sample)) { |
| // Did not pass time filter. |
| continue; |
| } |
| if (!filter->TaskFilterSample(sample)) { |
| // Did not pass task filter. |
| continue; |
| } |
| if (!filter->FilterSample(sample)) { |
| // Did not pass filter. |
| continue; |
| } |
| buffer->Add(BuildProcessedSample(sample, buffer->code_lookup_table())); |
| } |
| return buffer; |
| } |
| |
| ProcessedSample* SampleBuffer::BuildProcessedSample( |
| Sample* sample, |
| const CodeLookupTable& clt) { |
| Thread* thread = Thread::Current(); |
| Zone* zone = thread->zone(); |
| |
| ProcessedSample* processed_sample = new (zone) ProcessedSample(); |
| |
| // Copy state bits from sample. |
| processed_sample->set_native_allocation_size_bytes( |
| sample->native_allocation_size_bytes()); |
| processed_sample->set_timestamp(sample->timestamp()); |
| processed_sample->set_tid(sample->tid()); |
| processed_sample->set_vm_tag(sample->vm_tag()); |
| processed_sample->set_user_tag(sample->user_tag()); |
| if (sample->is_allocation_sample()) { |
| processed_sample->set_allocation_cid(sample->allocation_cid()); |
| } |
| processed_sample->set_first_frame_executing(!sample->exit_frame_sample()); |
| |
| // Copy stack trace from sample(s). |
| bool truncated = false; |
| Sample* current = sample; |
| while (current != NULL) { |
| for (intptr_t i = 0; i < kSampleSize; i++) { |
| if (current->At(i) == 0) { |
| break; |
| } |
| processed_sample->Add(current->At(i)); |
| } |
| |
| truncated = truncated || current->truncated_trace(); |
| current = Next(current); |
| } |
| |
| if (!sample->exit_frame_sample()) { |
| processed_sample->FixupCaller(clt, sample->pc_marker(), |
| sample->GetStackBuffer()); |
| } |
| |
| processed_sample->set_truncated(truncated); |
| return processed_sample; |
| } |
| |
| Sample* SampleBuffer::Next(Sample* sample) { |
| if (!sample->is_continuation_sample()) return NULL; |
| Sample* next_sample = At(sample->continuation_index()); |
| // Sanity check. |
| ASSERT(sample != next_sample); |
| // Detect invalid chaining. |
| if (sample->port() != next_sample->port()) { |
| return NULL; |
| } |
| if (sample->timestamp() != next_sample->timestamp()) { |
| return NULL; |
| } |
| if (sample->tid() != next_sample->tid()) { |
| return NULL; |
| } |
| return next_sample; |
| } |
| |
| ProcessedSample::ProcessedSample() |
| : pcs_(kSampleSize), |
| timestamp_(0), |
| vm_tag_(0), |
| user_tag_(0), |
| allocation_cid_(-1), |
| truncated_(false), |
| timeline_code_trie_(nullptr), |
| timeline_function_trie_(nullptr) {} |
| |
| void ProcessedSample::FixupCaller(const CodeLookupTable& clt, |
| uword pc_marker, |
| uword* stack_buffer) { |
| const CodeDescriptor* cd = clt.FindCode(At(0)); |
| if (cd == NULL) { |
| // No Dart code. |
| return; |
| } |
| if (cd->CompileTimestamp() > timestamp()) { |
| // Code compiled after sample. Ignore. |
| return; |
| } |
| CheckForMissingDartFrame(clt, cd, pc_marker, stack_buffer); |
| } |
| |
| void ProcessedSample::CheckForMissingDartFrame(const CodeLookupTable& clt, |
| const CodeDescriptor* cd, |
| uword pc_marker, |
| uword* stack_buffer) { |
| ASSERT(cd != NULL); |
| if (cd->code().IsBytecode()) { |
| // Bytecode frame build is atomic from the profiler's perspective: no |
| // missing frame. |
| return; |
| } |
| const Code& code = Code::Handle(Code::RawCast(cd->code().raw())); |
| ASSERT(!code.IsNull()); |
| // Some stubs (and intrinsics) do not push a frame onto the stack leaving |
| // the frame pointer in the caller. |
| // |
| // PC -> STUB |
| // FP -> DART3 <-+ |
| // DART2 <-| <- TOP FRAME RETURN ADDRESS. |
| // DART1 <-| |
| // ..... |
| // |
| // In this case, traversing the linked stack frames will not collect a PC |
| // inside DART3. The stack will incorrectly be: STUB, DART2, DART1. |
| // In Dart code, after pushing the FP onto the stack, an IP in the current |
| // function is pushed onto the stack as well. This stack slot is called |
| // the PC marker. We can use the PC marker to insert DART3 into the stack |
| // so that it will correctly be: STUB, DART3, DART2, DART1. Note the |
| // inserted PC may not accurately reflect the true return address into DART3. |
| |
| // The pc marker is our current best guess of a return address. |
| uword return_address = pc_marker; |
| |
| // Attempt to find a better return address. |
| ReturnAddressLocator ral(At(0), stack_buffer, code); |
| |
| if (!ral.LocateReturnAddress(&return_address)) { |
| ASSERT(return_address == pc_marker); |
| if (code.GetPrologueOffset() == 0) { |
| // Code has the prologue at offset 0. The frame is already setup and |
| // can be trusted. |
| return; |
| } |
| // Could not find a better return address than the pc_marker. |
| if (code.ContainsInstructionAt(return_address)) { |
| // PC marker is in the same code as pc, no missing frame. |
| return; |
| } |
| } |
| |
| if (clt.FindCode(return_address) == NULL) { |
| // Return address is not from a Dart code object. Do not insert. |
| return; |
| } |
| |
| if (return_address != 0) { |
| InsertAt(1, return_address); |
| } |
| } |
| |
| ProcessedSampleBuffer::ProcessedSampleBuffer() |
| : code_lookup_table_(new CodeLookupTable(Thread::Current())) { |
| ASSERT(code_lookup_table_ != NULL); |
| } |
| |
| #endif // !PRODUCT |
| |
| } // namespace dart |