| // Copyright 2016 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef V8_HEAP_EMBEDDER_TRACING_H_ |
| #define V8_HEAP_EMBEDDER_TRACING_H_ |
| |
| #include "include/v8.h" |
| #include "src/flags.h" |
| #include "src/globals.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| class Heap; |
| class JSObject; |
| |
| class V8_EXPORT_PRIVATE LocalEmbedderHeapTracer final { |
| public: |
| typedef std::pair<void*, void*> WrapperInfo; |
| typedef std::vector<WrapperInfo> WrapperCache; |
| |
| class V8_EXPORT_PRIVATE ProcessingScope { |
| public: |
| explicit ProcessingScope(LocalEmbedderHeapTracer* tracer); |
| ~ProcessingScope(); |
| |
| void TracePossibleWrapper(JSObject js_object); |
| |
| void AddWrapperInfoForTesting(WrapperInfo info); |
| |
| private: |
| static constexpr size_t kWrapperCacheSize = 1000; |
| |
| void FlushWrapperCacheIfFull(); |
| |
| LocalEmbedderHeapTracer* const tracer_; |
| WrapperCache wrapper_cache_; |
| }; |
| |
| explicit LocalEmbedderHeapTracer(Isolate* isolate) : isolate_(isolate) {} |
| |
| ~LocalEmbedderHeapTracer() { |
| if (remote_tracer_) remote_tracer_->isolate_ = nullptr; |
| } |
| |
| bool InUse() const { return remote_tracer_ != nullptr; } |
| EmbedderHeapTracer* remote_tracer() const { return remote_tracer_; } |
| |
| void SetRemoteTracer(EmbedderHeapTracer* tracer); |
| void TracePrologue(); |
| void TraceEpilogue(); |
| void EnterFinalPause(); |
| bool Trace(double deadline); |
| bool IsRemoteTracingDone(); |
| |
| void NotifyV8MarkingWorklistWasEmpty() { |
| num_v8_marking_worklist_was_empty_++; |
| } |
| |
| bool ShouldFinalizeIncrementalMarking() { |
| static const size_t kMaxIncrementalFixpointRounds = 3; |
| return !FLAG_incremental_marking_wrappers || !InUse() || |
| (IsRemoteTracingDone() && embedder_worklist_empty_) || |
| num_v8_marking_worklist_was_empty_ > kMaxIncrementalFixpointRounds; |
| } |
| |
| void SetEmbedderStackStateForNextFinalization( |
| EmbedderHeapTracer::EmbedderStackState stack_state); |
| |
| void SetEmbedderWorklistEmpty(bool is_empty) { |
| embedder_worklist_empty_ = is_empty; |
| } |
| |
| private: |
| Isolate* const isolate_; |
| EmbedderHeapTracer* remote_tracer_ = nullptr; |
| |
| size_t num_v8_marking_worklist_was_empty_ = 0; |
| EmbedderHeapTracer::EmbedderStackState embedder_stack_state_ = |
| EmbedderHeapTracer::kUnknown; |
| // Indicates whether the embedder worklist was observed empty on the main |
| // thread. This is opportunistic as concurrent marking tasks may hold local |
| // segments of potential embedder fields to move to the main thread. |
| bool embedder_worklist_empty_ = false; |
| |
| friend class EmbedderStackStateScope; |
| }; |
| |
| class V8_EXPORT_PRIVATE EmbedderStackStateScope final { |
| public: |
| EmbedderStackStateScope(LocalEmbedderHeapTracer* local_tracer, |
| EmbedderHeapTracer::EmbedderStackState stack_state) |
| : local_tracer_(local_tracer), |
| old_stack_state_(local_tracer_->embedder_stack_state_) { |
| local_tracer_->embedder_stack_state_ = stack_state; |
| } |
| |
| ~EmbedderStackStateScope() { |
| local_tracer_->embedder_stack_state_ = old_stack_state_; |
| } |
| |
| private: |
| LocalEmbedderHeapTracer* const local_tracer_; |
| const EmbedderHeapTracer::EmbedderStackState old_stack_state_; |
| }; |
| |
| } // namespace internal |
| } // namespace v8 |
| |
| #endif // V8_HEAP_EMBEDDER_TRACING_H_ |