| // Copyright 2012 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. |
| |
| #include "src/heap/incremental-marking.h" |
| |
| #include "src/code-stubs.h" |
| #include "src/compilation-cache.h" |
| #include "src/conversions.h" |
| #include "src/heap/gc-idle-time-handler.h" |
| #include "src/heap/gc-tracer.h" |
| #include "src/heap/mark-compact-inl.h" |
| #include "src/heap/objects-visiting.h" |
| #include "src/heap/objects-visiting-inl.h" |
| #include "src/tracing/trace-event.h" |
| #include "src/v8.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| IncrementalMarking::StepActions IncrementalMarking::IdleStepActions() { |
| return StepActions(IncrementalMarking::NO_GC_VIA_STACK_GUARD, |
| IncrementalMarking::FORCE_MARKING, |
| IncrementalMarking::DO_NOT_FORCE_COMPLETION); |
| } |
| |
| IncrementalMarking::IncrementalMarking(Heap* heap) |
| : heap_(heap), |
| observer_(*this, kAllocatedThreshold), |
| state_(STOPPED), |
| is_compacting_(false), |
| steps_count_(0), |
| old_generation_space_available_at_start_of_incremental_(0), |
| old_generation_space_used_at_start_of_incremental_(0), |
| bytes_rescanned_(0), |
| should_hurry_(false), |
| marking_speed_(0), |
| bytes_scanned_(0), |
| allocated_(0), |
| write_barriers_invoked_since_last_step_(0), |
| idle_marking_delay_counter_(0), |
| no_marking_scope_depth_(0), |
| unscanned_bytes_of_large_object_(0), |
| was_activated_(false), |
| finalize_marking_completed_(false), |
| incremental_marking_finalization_rounds_(0), |
| request_type_(COMPLETE_MARKING) {} |
| |
| bool IncrementalMarking::BaseRecordWrite(HeapObject* obj, Object* value) { |
| HeapObject* value_heap_obj = HeapObject::cast(value); |
| MarkBit value_bit = Marking::MarkBitFrom(value_heap_obj); |
| DCHECK(!Marking::IsImpossible(value_bit)); |
| |
| MarkBit obj_bit = Marking::MarkBitFrom(obj); |
| DCHECK(!Marking::IsImpossible(obj_bit)); |
| bool is_black = Marking::IsBlack(obj_bit); |
| |
| if (is_black && Marking::IsWhite(value_bit)) { |
| WhiteToGreyAndPush(value_heap_obj, value_bit); |
| RestartIfNotMarking(); |
| } |
| return is_compacting_ && is_black; |
| } |
| |
| |
| void IncrementalMarking::RecordWriteSlow(HeapObject* obj, Object** slot, |
| Object* value) { |
| if (BaseRecordWrite(obj, value) && slot != NULL) { |
| // Object is not going to be rescanned we need to record the slot. |
| heap_->mark_compact_collector()->RecordSlot(obj, slot, value); |
| } |
| } |
| |
| |
| void IncrementalMarking::RecordWriteFromCode(HeapObject* obj, Object** slot, |
| Isolate* isolate) { |
| DCHECK(obj->IsHeapObject()); |
| IncrementalMarking* marking = isolate->heap()->incremental_marking(); |
| |
| MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address()); |
| int counter = chunk->write_barrier_counter(); |
| if (counter < (MemoryChunk::kWriteBarrierCounterGranularity / 2)) { |
| marking->write_barriers_invoked_since_last_step_ += |
| MemoryChunk::kWriteBarrierCounterGranularity - |
| chunk->write_barrier_counter(); |
| chunk->set_write_barrier_counter( |
| MemoryChunk::kWriteBarrierCounterGranularity); |
| } |
| |
| marking->RecordWrite(obj, slot, *slot); |
| } |
| |
| // static |
| void IncrementalMarking::RecordWriteOfCodeEntryFromCode(JSFunction* host, |
| Object** slot, |
| Isolate* isolate) { |
| DCHECK(host->IsJSFunction()); |
| IncrementalMarking* marking = isolate->heap()->incremental_marking(); |
| Code* value = Code::cast( |
| Code::GetObjectFromEntryAddress(reinterpret_cast<Address>(slot))); |
| marking->RecordWriteOfCodeEntry(host, slot, value); |
| } |
| |
| void IncrementalMarking::RecordCodeTargetPatch(Code* host, Address pc, |
| HeapObject* value) { |
| if (IsMarking()) { |
| RelocInfo rinfo(heap_->isolate(), pc, RelocInfo::CODE_TARGET, 0, host); |
| RecordWriteIntoCode(host, &rinfo, value); |
| } |
| } |
| |
| |
| void IncrementalMarking::RecordCodeTargetPatch(Address pc, HeapObject* value) { |
| if (IsMarking()) { |
| Code* host = heap_->isolate() |
| ->inner_pointer_to_code_cache() |
| ->GcSafeFindCodeForInnerPointer(pc); |
| RelocInfo rinfo(heap_->isolate(), pc, RelocInfo::CODE_TARGET, 0, host); |
| RecordWriteIntoCode(host, &rinfo, value); |
| } |
| } |
| |
| |
| void IncrementalMarking::RecordWriteOfCodeEntrySlow(JSFunction* host, |
| Object** slot, |
| Code* value) { |
| if (BaseRecordWrite(host, value)) { |
| DCHECK(slot != NULL); |
| heap_->mark_compact_collector()->RecordCodeEntrySlot( |
| host, reinterpret_cast<Address>(slot), value); |
| } |
| } |
| |
| |
| void IncrementalMarking::RecordWriteIntoCodeSlow(HeapObject* obj, |
| RelocInfo* rinfo, |
| Object* value) { |
| if (BaseRecordWrite(obj, value)) { |
| // Object is not going to be rescanned. We need to record the slot. |
| heap_->mark_compact_collector()->RecordRelocSlot(rinfo, value); |
| } |
| } |
| |
| |
| void IncrementalMarking::RecordWrites(HeapObject* obj) { |
| if (IsMarking()) { |
| MarkBit obj_bit = Marking::MarkBitFrom(obj); |
| if (Marking::IsBlack(obj_bit)) { |
| MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address()); |
| if (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR)) { |
| chunk->set_progress_bar(0); |
| } |
| BlackToGreyAndUnshift(obj, obj_bit); |
| RestartIfNotMarking(); |
| } |
| } |
| } |
| |
| |
| void IncrementalMarking::BlackToGreyAndUnshift(HeapObject* obj, |
| MarkBit mark_bit) { |
| DCHECK(Marking::MarkBitFrom(obj) == mark_bit); |
| DCHECK(obj->Size() >= 2 * kPointerSize); |
| DCHECK(IsMarking()); |
| Marking::BlackToGrey(mark_bit); |
| int obj_size = obj->Size(); |
| MemoryChunk::IncrementLiveBytesFromGC(obj, -obj_size); |
| bytes_scanned_ -= obj_size; |
| int64_t old_bytes_rescanned = bytes_rescanned_; |
| bytes_rescanned_ = old_bytes_rescanned + obj_size; |
| if ((bytes_rescanned_ >> 20) != (old_bytes_rescanned >> 20)) { |
| if (bytes_rescanned_ > 2 * heap_->PromotedSpaceSizeOfObjects()) { |
| // If we have queued twice the heap size for rescanning then we are |
| // going around in circles, scanning the same objects again and again |
| // as the program mutates the heap faster than we can incrementally |
| // trace it. In this case we switch to non-incremental marking in |
| // order to finish off this marking phase. |
| if (FLAG_trace_incremental_marking) { |
| PrintIsolate( |
| heap()->isolate(), |
| "Hurrying incremental marking because of lack of progress\n"); |
| } |
| marking_speed_ = kMaxMarkingSpeed; |
| } |
| } |
| |
| heap_->mark_compact_collector()->marking_deque()->Unshift(obj); |
| } |
| |
| |
| void IncrementalMarking::WhiteToGreyAndPush(HeapObject* obj, MarkBit mark_bit) { |
| Marking::WhiteToGrey(mark_bit); |
| heap_->mark_compact_collector()->marking_deque()->Push(obj); |
| } |
| |
| |
| static void MarkObjectGreyDoNotEnqueue(Object* obj) { |
| if (obj->IsHeapObject()) { |
| HeapObject* heap_obj = HeapObject::cast(obj); |
| MarkBit mark_bit = Marking::MarkBitFrom(HeapObject::cast(obj)); |
| if (Marking::IsBlack(mark_bit)) { |
| MemoryChunk::IncrementLiveBytesFromGC(heap_obj, -heap_obj->Size()); |
| } |
| Marking::AnyToGrey(mark_bit); |
| } |
| } |
| |
| |
| static inline void MarkBlackOrKeepBlack(HeapObject* heap_object, |
| MarkBit mark_bit, int size) { |
| DCHECK(!Marking::IsImpossible(mark_bit)); |
| if (Marking::IsBlack(mark_bit)) return; |
| Marking::MarkBlack(mark_bit); |
| MemoryChunk::IncrementLiveBytesFromGC(heap_object, size); |
| } |
| |
| |
| class IncrementalMarkingMarkingVisitor |
| : public StaticMarkingVisitor<IncrementalMarkingMarkingVisitor> { |
| public: |
| static void Initialize() { |
| StaticMarkingVisitor<IncrementalMarkingMarkingVisitor>::Initialize(); |
| table_.Register(kVisitFixedArray, &VisitFixedArrayIncremental); |
| table_.Register(kVisitNativeContext, &VisitNativeContextIncremental); |
| table_.Register(kVisitJSRegExp, &VisitJSRegExp); |
| } |
| |
| static const int kProgressBarScanningChunk = 32 * 1024; |
| |
| static void VisitFixedArrayIncremental(Map* map, HeapObject* object) { |
| MemoryChunk* chunk = MemoryChunk::FromAddress(object->address()); |
| // TODO(mstarzinger): Move setting of the flag to the allocation site of |
| // the array. The visitor should just check the flag. |
| if (FLAG_use_marking_progress_bar && |
| chunk->owner()->identity() == LO_SPACE) { |
| chunk->SetFlag(MemoryChunk::HAS_PROGRESS_BAR); |
| } |
| if (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR)) { |
| Heap* heap = map->GetHeap(); |
| // When using a progress bar for large fixed arrays, scan only a chunk of |
| // the array and try to push it onto the marking deque again until it is |
| // fully scanned. Fall back to scanning it through to the end in case this |
| // fails because of a full deque. |
| int object_size = FixedArray::BodyDescriptor::SizeOf(map, object); |
| int start_offset = |
| Max(FixedArray::BodyDescriptor::kStartOffset, chunk->progress_bar()); |
| int end_offset = |
| Min(object_size, start_offset + kProgressBarScanningChunk); |
| int already_scanned_offset = start_offset; |
| bool scan_until_end = false; |
| do { |
| VisitPointers(heap, object, HeapObject::RawField(object, start_offset), |
| HeapObject::RawField(object, end_offset)); |
| start_offset = end_offset; |
| end_offset = Min(object_size, end_offset + kProgressBarScanningChunk); |
| scan_until_end = |
| heap->mark_compact_collector()->marking_deque()->IsFull(); |
| } while (scan_until_end && start_offset < object_size); |
| chunk->set_progress_bar(start_offset); |
| if (start_offset < object_size) { |
| if (Marking::IsGrey(Marking::MarkBitFrom(object))) { |
| heap->mark_compact_collector()->marking_deque()->Unshift(object); |
| } else { |
| DCHECK(Marking::IsBlack(Marking::MarkBitFrom(object))); |
| heap->mark_compact_collector()->UnshiftBlack(object); |
| } |
| heap->incremental_marking()->NotifyIncompleteScanOfObject( |
| object_size - (start_offset - already_scanned_offset)); |
| } |
| } else { |
| FixedArrayVisitor::Visit(map, object); |
| } |
| } |
| |
| static void VisitNativeContextIncremental(Map* map, HeapObject* object) { |
| Context* context = Context::cast(object); |
| |
| // We will mark cache black with a separate pass when we finish marking. |
| // Note that GC can happen when the context is not fully initialized, |
| // so the cache can be undefined. |
| Object* cache = context->get(Context::NORMALIZED_MAP_CACHE_INDEX); |
| if (!cache->IsUndefined()) { |
| MarkObjectGreyDoNotEnqueue(cache); |
| } |
| VisitNativeContext(map, context); |
| } |
| |
| INLINE(static void VisitPointer(Heap* heap, HeapObject* object, Object** p)) { |
| Object* target = *p; |
| if (target->IsHeapObject()) { |
| heap->mark_compact_collector()->RecordSlot(object, p, target); |
| MarkObject(heap, target); |
| } |
| } |
| |
| INLINE(static void VisitPointers(Heap* heap, HeapObject* object, |
| Object** start, Object** end)) { |
| for (Object** p = start; p < end; p++) { |
| Object* target = *p; |
| if (target->IsHeapObject()) { |
| heap->mark_compact_collector()->RecordSlot(object, p, target); |
| MarkObject(heap, target); |
| } |
| } |
| } |
| |
| // Marks the object grey and pushes it on the marking stack. |
| INLINE(static void MarkObject(Heap* heap, Object* obj)) { |
| IncrementalMarking::MarkObject(heap, HeapObject::cast(obj)); |
| } |
| |
| // Marks the object black without pushing it on the marking stack. |
| // Returns true if object needed marking and false otherwise. |
| INLINE(static bool MarkObjectWithoutPush(Heap* heap, Object* obj)) { |
| HeapObject* heap_object = HeapObject::cast(obj); |
| MarkBit mark_bit = Marking::MarkBitFrom(heap_object); |
| if (Marking::IsWhite(mark_bit)) { |
| Marking::MarkBlack(mark_bit); |
| MemoryChunk::IncrementLiveBytesFromGC(heap_object, heap_object->Size()); |
| return true; |
| } |
| return false; |
| } |
| }; |
| |
| |
| class IncrementalMarkingRootMarkingVisitor : public ObjectVisitor { |
| public: |
| explicit IncrementalMarkingRootMarkingVisitor( |
| IncrementalMarking* incremental_marking) |
| : heap_(incremental_marking->heap()) {} |
| |
| void VisitPointer(Object** p) override { MarkObjectByPointer(p); } |
| |
| void VisitPointers(Object** start, Object** end) override { |
| for (Object** p = start; p < end; p++) MarkObjectByPointer(p); |
| } |
| |
| private: |
| void MarkObjectByPointer(Object** p) { |
| Object* obj = *p; |
| if (!obj->IsHeapObject()) return; |
| |
| IncrementalMarking::MarkObject(heap_, HeapObject::cast(obj)); |
| } |
| |
| Heap* heap_; |
| }; |
| |
| |
| void IncrementalMarking::Initialize() { |
| IncrementalMarkingMarkingVisitor::Initialize(); |
| } |
| |
| |
| void IncrementalMarking::SetOldSpacePageFlags(MemoryChunk* chunk, |
| bool is_marking, |
| bool is_compacting) { |
| if (is_marking) { |
| chunk->SetFlag(MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING); |
| chunk->SetFlag(MemoryChunk::POINTERS_FROM_HERE_ARE_INTERESTING); |
| } else { |
| chunk->ClearFlag(MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING); |
| chunk->SetFlag(MemoryChunk::POINTERS_FROM_HERE_ARE_INTERESTING); |
| } |
| } |
| |
| |
| void IncrementalMarking::SetNewSpacePageFlags(MemoryChunk* chunk, |
| bool is_marking) { |
| chunk->SetFlag(MemoryChunk::POINTERS_TO_HERE_ARE_INTERESTING); |
| if (is_marking) { |
| chunk->SetFlag(MemoryChunk::POINTERS_FROM_HERE_ARE_INTERESTING); |
| } else { |
| chunk->ClearFlag(MemoryChunk::POINTERS_FROM_HERE_ARE_INTERESTING); |
| } |
| } |
| |
| |
| void IncrementalMarking::DeactivateIncrementalWriteBarrierForSpace( |
| PagedSpace* space) { |
| PageIterator it(space); |
| while (it.has_next()) { |
| Page* p = it.next(); |
| SetOldSpacePageFlags(p, false, false); |
| } |
| } |
| |
| |
| void IncrementalMarking::DeactivateIncrementalWriteBarrierForSpace( |
| NewSpace* space) { |
| NewSpacePageIterator it(space); |
| while (it.has_next()) { |
| NewSpacePage* p = it.next(); |
| SetNewSpacePageFlags(p, false); |
| } |
| } |
| |
| |
| void IncrementalMarking::DeactivateIncrementalWriteBarrier() { |
| DeactivateIncrementalWriteBarrierForSpace(heap_->old_space()); |
| DeactivateIncrementalWriteBarrierForSpace(heap_->map_space()); |
| DeactivateIncrementalWriteBarrierForSpace(heap_->code_space()); |
| DeactivateIncrementalWriteBarrierForSpace(heap_->new_space()); |
| |
| LargePage* lop = heap_->lo_space()->first_page(); |
| while (lop->is_valid()) { |
| SetOldSpacePageFlags(lop, false, false); |
| lop = lop->next_page(); |
| } |
| } |
| |
| |
| void IncrementalMarking::ActivateIncrementalWriteBarrier(PagedSpace* space) { |
| PageIterator it(space); |
| while (it.has_next()) { |
| Page* p = it.next(); |
| SetOldSpacePageFlags(p, true, is_compacting_); |
| } |
| } |
| |
| |
| void IncrementalMarking::ActivateIncrementalWriteBarrier(NewSpace* space) { |
| NewSpacePageIterator it(space->ToSpaceStart(), space->ToSpaceEnd()); |
| while (it.has_next()) { |
| NewSpacePage* p = it.next(); |
| SetNewSpacePageFlags(p, true); |
| } |
| } |
| |
| |
| void IncrementalMarking::ActivateIncrementalWriteBarrier() { |
| ActivateIncrementalWriteBarrier(heap_->old_space()); |
| ActivateIncrementalWriteBarrier(heap_->map_space()); |
| ActivateIncrementalWriteBarrier(heap_->code_space()); |
| ActivateIncrementalWriteBarrier(heap_->new_space()); |
| |
| LargePage* lop = heap_->lo_space()->first_page(); |
| while (lop->is_valid()) { |
| SetOldSpacePageFlags(lop, true, is_compacting_); |
| lop = lop->next_page(); |
| } |
| } |
| |
| |
| bool IncrementalMarking::ShouldActivateEvenWithoutIdleNotification() { |
| #ifndef DEBUG |
| static const intptr_t kActivationThreshold = 8 * MB; |
| #else |
| // TODO(gc) consider setting this to some low level so that some |
| // debug tests run with incremental marking and some without. |
| static const intptr_t kActivationThreshold = 0; |
| #endif |
| // Don't switch on for very small heaps. |
| return CanBeActivated() && |
| heap_->PromotedSpaceSizeOfObjects() > kActivationThreshold && |
| heap_->HeapIsFullEnoughToStartIncrementalMarking( |
| heap_->old_generation_allocation_limit()); |
| } |
| |
| |
| bool IncrementalMarking::WasActivated() { return was_activated_; } |
| |
| |
| bool IncrementalMarking::CanBeActivated() { |
| // Only start incremental marking in a safe state: 1) when incremental |
| // marking is turned on, 2) when we are currently not in a GC, and |
| // 3) when we are currently not serializing or deserializing the heap. |
| return FLAG_incremental_marking && heap_->gc_state() == Heap::NOT_IN_GC && |
| heap_->deserialization_complete() && |
| !heap_->isolate()->serializer_enabled(); |
| } |
| |
| |
| void IncrementalMarking::ActivateGeneratedStub(Code* stub) { |
| DCHECK(RecordWriteStub::GetMode(stub) == RecordWriteStub::STORE_BUFFER_ONLY); |
| |
| if (!IsMarking()) { |
| // Initially stub is generated in STORE_BUFFER_ONLY mode thus |
| // we don't need to do anything if incremental marking is |
| // not active. |
| } else if (IsCompacting()) { |
| RecordWriteStub::Patch(stub, RecordWriteStub::INCREMENTAL_COMPACTION); |
| } else { |
| RecordWriteStub::Patch(stub, RecordWriteStub::INCREMENTAL); |
| } |
| } |
| |
| |
| void IncrementalMarking::NotifyOfHighPromotionRate() { |
| if (IsMarking()) { |
| if (marking_speed_ < kFastMarking) { |
| if (FLAG_trace_gc) { |
| PrintIsolate(heap()->isolate(), |
| "Increasing marking speed to %d " |
| "due to high promotion rate\n", |
| static_cast<int>(kFastMarking)); |
| } |
| marking_speed_ = kFastMarking; |
| } |
| } |
| } |
| |
| |
| static void PatchIncrementalMarkingRecordWriteStubs( |
| Heap* heap, RecordWriteStub::Mode mode) { |
| UnseededNumberDictionary* stubs = heap->code_stubs(); |
| |
| int capacity = stubs->Capacity(); |
| for (int i = 0; i < capacity; i++) { |
| Object* k = stubs->KeyAt(i); |
| if (stubs->IsKey(k)) { |
| uint32_t key = NumberToUint32(k); |
| |
| if (CodeStub::MajorKeyFromKey(key) == CodeStub::RecordWrite) { |
| Object* e = stubs->ValueAt(i); |
| if (e->IsCode()) { |
| RecordWriteStub::Patch(Code::cast(e), mode); |
| } |
| } |
| } |
| } |
| } |
| |
| |
| void IncrementalMarking::Start(const char* reason) { |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Start (%s)\n", |
| (reason == nullptr) ? "unknown reason" : reason); |
| } |
| DCHECK(FLAG_incremental_marking); |
| DCHECK(state_ == STOPPED); |
| DCHECK(heap_->gc_state() == Heap::NOT_IN_GC); |
| DCHECK(!heap_->isolate()->serializer_enabled()); |
| |
| HistogramTimerScope incremental_marking_scope( |
| heap_->isolate()->counters()->gc_incremental_marking_start()); |
| TRACE_EVENT0("v8", "V8.GCIncrementalMarkingStart"); |
| ResetStepCounters(); |
| |
| was_activated_ = true; |
| |
| if (!heap_->mark_compact_collector()->sweeping_in_progress()) { |
| StartMarking(); |
| } else { |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Start sweeping.\n"); |
| } |
| state_ = SWEEPING; |
| } |
| |
| heap_->new_space()->AddAllocationObserver(&observer_); |
| |
| incremental_marking_job()->Start(heap_); |
| } |
| |
| |
| void IncrementalMarking::StartMarking() { |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Start marking\n"); |
| } |
| |
| is_compacting_ = !FLAG_never_compact && |
| heap_->mark_compact_collector()->StartCompaction( |
| MarkCompactCollector::INCREMENTAL_COMPACTION); |
| |
| state_ = MARKING; |
| |
| RecordWriteStub::Mode mode = is_compacting_ |
| ? RecordWriteStub::INCREMENTAL_COMPACTION |
| : RecordWriteStub::INCREMENTAL; |
| |
| PatchIncrementalMarkingRecordWriteStubs(heap_, mode); |
| |
| heap_->mark_compact_collector()->EnsureMarkingDequeIsCommittedAndInitialize( |
| MarkCompactCollector::kMaxMarkingDequeSize); |
| |
| ActivateIncrementalWriteBarrier(); |
| |
| // Marking bits are cleared by the sweeper. |
| #ifdef VERIFY_HEAP |
| if (FLAG_verify_heap) { |
| heap_->mark_compact_collector()->VerifyMarkbitsAreClean(); |
| } |
| #endif |
| |
| heap_->CompletelyClearInstanceofCache(); |
| heap_->isolate()->compilation_cache()->MarkCompactPrologue(); |
| |
| if (FLAG_cleanup_code_caches_at_gc) { |
| // We will mark cache black with a separate pass |
| // when we finish marking. |
| MarkObjectGreyDoNotEnqueue(heap_->polymorphic_code_cache()); |
| } |
| |
| // Mark strong roots grey. |
| IncrementalMarkingRootMarkingVisitor visitor(this); |
| heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG); |
| |
| // Ready to start incremental marking. |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Running\n"); |
| } |
| } |
| |
| |
| void IncrementalMarking::MarkRoots() { |
| DCHECK(!finalize_marking_completed_); |
| DCHECK(IsMarking()); |
| |
| IncrementalMarkingRootMarkingVisitor visitor(this); |
| heap_->IterateStrongRoots(&visitor, VISIT_ONLY_STRONG); |
| } |
| |
| |
| void IncrementalMarking::MarkObjectGroups() { |
| DCHECK(!finalize_marking_completed_); |
| DCHECK(IsMarking()); |
| |
| IncrementalMarkingRootMarkingVisitor visitor(this); |
| heap_->mark_compact_collector()->MarkImplicitRefGroups(&MarkObject); |
| heap_->isolate()->global_handles()->IterateObjectGroups( |
| &visitor, &MarkCompactCollector::IsUnmarkedHeapObjectWithHeap); |
| heap_->isolate()->global_handles()->RemoveImplicitRefGroups(); |
| heap_->isolate()->global_handles()->RemoveObjectGroups(); |
| } |
| |
| |
| void IncrementalMarking::ProcessWeakCells() { |
| DCHECK(!finalize_marking_completed_); |
| DCHECK(IsMarking()); |
| |
| Object* the_hole_value = heap()->the_hole_value(); |
| Object* weak_cell_obj = heap()->encountered_weak_cells(); |
| Object* weak_cell_head = Smi::FromInt(0); |
| WeakCell* prev_weak_cell_obj = NULL; |
| while (weak_cell_obj != Smi::FromInt(0)) { |
| WeakCell* weak_cell = reinterpret_cast<WeakCell*>(weak_cell_obj); |
| // We do not insert cleared weak cells into the list, so the value |
| // cannot be a Smi here. |
| HeapObject* value = HeapObject::cast(weak_cell->value()); |
| // Remove weak cells with live objects from the list, they do not need |
| // clearing. |
| if (MarkCompactCollector::IsMarked(value)) { |
| // Record slot, if value is pointing to an evacuation candidate. |
| Object** slot = HeapObject::RawField(weak_cell, WeakCell::kValueOffset); |
| heap_->mark_compact_collector()->RecordSlot(weak_cell, slot, *slot); |
| // Remove entry somewhere after top. |
| if (prev_weak_cell_obj != NULL) { |
| prev_weak_cell_obj->set_next(weak_cell->next()); |
| } |
| weak_cell_obj = weak_cell->next(); |
| weak_cell->clear_next(the_hole_value); |
| } else { |
| if (weak_cell_head == Smi::FromInt(0)) { |
| weak_cell_head = weak_cell; |
| } |
| prev_weak_cell_obj = weak_cell; |
| weak_cell_obj = weak_cell->next(); |
| } |
| } |
| // Top may have changed. |
| heap()->set_encountered_weak_cells(weak_cell_head); |
| } |
| |
| |
| bool ShouldRetainMap(Map* map, int age) { |
| if (age == 0) { |
| // The map has aged. Do not retain this map. |
| return false; |
| } |
| Object* constructor = map->GetConstructor(); |
| if (!constructor->IsHeapObject() || |
| Marking::IsWhite(Marking::MarkBitFrom(HeapObject::cast(constructor)))) { |
| // The constructor is dead, no new objects with this map can |
| // be created. Do not retain this map. |
| return false; |
| } |
| return true; |
| } |
| |
| |
| void IncrementalMarking::RetainMaps() { |
| // Do not retain dead maps if flag disables it or there is |
| // - memory pressure (reduce_memory_footprint_), |
| // - GC is requested by tests or dev-tools (abort_incremental_marking_). |
| bool map_retaining_is_disabled = heap()->ShouldReduceMemory() || |
| heap()->ShouldAbortIncrementalMarking() || |
| FLAG_retain_maps_for_n_gc == 0; |
| ArrayList* retained_maps = heap()->retained_maps(); |
| int length = retained_maps->Length(); |
| // The number_of_disposed_maps separates maps in the retained_maps |
| // array that were created before and after context disposal. |
| // We do not age and retain disposed maps to avoid memory leaks. |
| int number_of_disposed_maps = heap()->number_of_disposed_maps_; |
| for (int i = 0; i < length; i += 2) { |
| DCHECK(retained_maps->Get(i)->IsWeakCell()); |
| WeakCell* cell = WeakCell::cast(retained_maps->Get(i)); |
| if (cell->cleared()) continue; |
| int age = Smi::cast(retained_maps->Get(i + 1))->value(); |
| int new_age; |
| Map* map = Map::cast(cell->value()); |
| MarkBit map_mark = Marking::MarkBitFrom(map); |
| if (i >= number_of_disposed_maps && !map_retaining_is_disabled && |
| Marking::IsWhite(map_mark)) { |
| if (ShouldRetainMap(map, age)) { |
| MarkObject(heap(), map); |
| } |
| Object* prototype = map->prototype(); |
| if (age > 0 && prototype->IsHeapObject() && |
| Marking::IsWhite(Marking::MarkBitFrom(HeapObject::cast(prototype)))) { |
| // The prototype is not marked, age the map. |
| new_age = age - 1; |
| } else { |
| // The prototype and the constructor are marked, this map keeps only |
| // transition tree alive, not JSObjects. Do not age the map. |
| new_age = age; |
| } |
| } else { |
| new_age = FLAG_retain_maps_for_n_gc; |
| } |
| // Compact the array and update the age. |
| if (new_age != age) { |
| retained_maps->Set(i + 1, Smi::FromInt(new_age)); |
| } |
| } |
| } |
| |
| |
| void IncrementalMarking::FinalizeIncrementally() { |
| DCHECK(!finalize_marking_completed_); |
| DCHECK(IsMarking()); |
| |
| double start = heap_->MonotonicallyIncreasingTimeInMs(); |
| |
| int old_marking_deque_top = |
| heap_->mark_compact_collector()->marking_deque()->top(); |
| |
| // After finishing incremental marking, we try to discover all unmarked |
| // objects to reduce the marking load in the final pause. |
| // 1) We scan and mark the roots again to find all changes to the root set. |
| // 2) We mark the object groups. |
| // 3) Age and retain maps embedded in optimized code. |
| // 4) Remove weak cell with live values from the list of weak cells, they |
| // do not need processing during GC. |
| MarkRoots(); |
| MarkObjectGroups(); |
| if (incremental_marking_finalization_rounds_ == 0) { |
| // Map retaining is needed for perfromance, not correctness, |
| // so we can do it only once at the beginning of the finalization. |
| RetainMaps(); |
| } |
| ProcessWeakCells(); |
| |
| int marking_progress = |
| abs(old_marking_deque_top - |
| heap_->mark_compact_collector()->marking_deque()->top()); |
| |
| double end = heap_->MonotonicallyIncreasingTimeInMs(); |
| double delta = end - start; |
| heap_->tracer()->AddMarkingTime(delta); |
| heap_->tracer()->AddIncrementalMarkingFinalizationStep(delta); |
| if (FLAG_trace_incremental_marking) { |
| PrintF( |
| "[IncrementalMarking] Finalize incrementally round %d, " |
| "spent %d ms, marking progress %d.\n", |
| static_cast<int>(delta), incremental_marking_finalization_rounds_, |
| marking_progress); |
| } |
| |
| ++incremental_marking_finalization_rounds_; |
| if ((incremental_marking_finalization_rounds_ >= |
| FLAG_max_incremental_marking_finalization_rounds) || |
| (marking_progress < |
| FLAG_min_progress_during_incremental_marking_finalization)) { |
| finalize_marking_completed_ = true; |
| } |
| } |
| |
| |
| void IncrementalMarking::UpdateMarkingDequeAfterScavenge() { |
| if (!IsMarking()) return; |
| |
| MarkingDeque* marking_deque = |
| heap_->mark_compact_collector()->marking_deque(); |
| int current = marking_deque->bottom(); |
| int mask = marking_deque->mask(); |
| int limit = marking_deque->top(); |
| HeapObject** array = marking_deque->array(); |
| int new_top = current; |
| |
| Map* filler_map = heap_->one_pointer_filler_map(); |
| |
| while (current != limit) { |
| HeapObject* obj = array[current]; |
| DCHECK(obj->IsHeapObject()); |
| current = ((current + 1) & mask); |
| // Only pointers to from space have to be updated. |
| if (heap_->InFromSpace(obj)) { |
| MapWord map_word = obj->map_word(); |
| // There may be objects on the marking deque that do not exist anymore, |
| // e.g. left trimmed objects or objects from the root set (frames). |
| // If these object are dead at scavenging time, their marking deque |
| // entries will not point to forwarding addresses. Hence, we can discard |
| // them. |
| if (map_word.IsForwardingAddress()) { |
| HeapObject* dest = map_word.ToForwardingAddress(); |
| array[new_top] = dest; |
| new_top = ((new_top + 1) & mask); |
| DCHECK(new_top != marking_deque->bottom()); |
| #ifdef DEBUG |
| MarkBit mark_bit = Marking::MarkBitFrom(obj); |
| DCHECK(Marking::IsGrey(mark_bit) || |
| (obj->IsFiller() && Marking::IsWhite(mark_bit))); |
| #endif |
| } |
| } else if (obj->map() != filler_map) { |
| // Skip one word filler objects that appear on the |
| // stack when we perform in place array shift. |
| array[new_top] = obj; |
| new_top = ((new_top + 1) & mask); |
| DCHECK(new_top != marking_deque->bottom()); |
| #ifdef DEBUG |
| MarkBit mark_bit = Marking::MarkBitFrom(obj); |
| MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address()); |
| DCHECK(Marking::IsGrey(mark_bit) || |
| (obj->IsFiller() && Marking::IsWhite(mark_bit)) || |
| (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR) && |
| Marking::IsBlack(mark_bit))); |
| #endif |
| } |
| } |
| marking_deque->set_top(new_top); |
| } |
| |
| |
| void IncrementalMarking::VisitObject(Map* map, HeapObject* obj, int size) { |
| MarkObject(heap_, map); |
| |
| IncrementalMarkingMarkingVisitor::IterateBody(map, obj); |
| |
| MarkBit mark_bit = Marking::MarkBitFrom(obj); |
| #if ENABLE_SLOW_DCHECKS |
| MemoryChunk* chunk = MemoryChunk::FromAddress(obj->address()); |
| SLOW_DCHECK(Marking::IsGrey(mark_bit) || |
| (obj->IsFiller() && Marking::IsWhite(mark_bit)) || |
| (chunk->IsFlagSet(MemoryChunk::HAS_PROGRESS_BAR) && |
| Marking::IsBlack(mark_bit))); |
| #endif |
| MarkBlackOrKeepBlack(obj, mark_bit, size); |
| } |
| |
| |
| void IncrementalMarking::MarkObject(Heap* heap, HeapObject* obj) { |
| MarkBit mark_bit = Marking::MarkBitFrom(obj); |
| if (Marking::IsWhite(mark_bit)) { |
| heap->incremental_marking()->WhiteToGreyAndPush(obj, mark_bit); |
| } |
| } |
| |
| |
| intptr_t IncrementalMarking::ProcessMarkingDeque(intptr_t bytes_to_process) { |
| intptr_t bytes_processed = 0; |
| Map* one_pointer_filler_map = heap_->one_pointer_filler_map(); |
| Map* two_pointer_filler_map = heap_->two_pointer_filler_map(); |
| MarkingDeque* marking_deque = |
| heap_->mark_compact_collector()->marking_deque(); |
| while (!marking_deque->IsEmpty() && bytes_processed < bytes_to_process) { |
| HeapObject* obj = marking_deque->Pop(); |
| |
| // Explicitly skip one and two word fillers. Incremental markbit patterns |
| // are correct only for objects that occupy at least two words. |
| // Moreover, slots filtering for left-trimmed arrays works only when |
| // the distance between the old array start and the new array start |
| // is greater than two if both starts are marked. |
| Map* map = obj->map(); |
| if (map == one_pointer_filler_map || map == two_pointer_filler_map) |
| continue; |
| |
| int size = obj->SizeFromMap(map); |
| unscanned_bytes_of_large_object_ = 0; |
| VisitObject(map, obj, size); |
| bytes_processed += size - unscanned_bytes_of_large_object_; |
| } |
| return bytes_processed; |
| } |
| |
| |
| void IncrementalMarking::ProcessMarkingDeque() { |
| Map* filler_map = heap_->one_pointer_filler_map(); |
| MarkingDeque* marking_deque = |
| heap_->mark_compact_collector()->marking_deque(); |
| while (!marking_deque->IsEmpty()) { |
| HeapObject* obj = marking_deque->Pop(); |
| |
| // Explicitly skip one word fillers. Incremental markbit patterns are |
| // correct only for objects that occupy at least two words. |
| Map* map = obj->map(); |
| if (map == filler_map) continue; |
| |
| VisitObject(map, obj, obj->SizeFromMap(map)); |
| } |
| } |
| |
| |
| void IncrementalMarking::Hurry() { |
| if (state() == MARKING) { |
| double start = 0.0; |
| if (FLAG_trace_incremental_marking || FLAG_print_cumulative_gc_stat) { |
| start = heap_->MonotonicallyIncreasingTimeInMs(); |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Hurry\n"); |
| } |
| } |
| // TODO(gc) hurry can mark objects it encounters black as mutator |
| // was stopped. |
| ProcessMarkingDeque(); |
| state_ = COMPLETE; |
| if (FLAG_trace_incremental_marking || FLAG_print_cumulative_gc_stat) { |
| double end = heap_->MonotonicallyIncreasingTimeInMs(); |
| double delta = end - start; |
| heap_->tracer()->AddMarkingTime(delta); |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Complete (hurry), spent %d ms.\n", |
| static_cast<int>(delta)); |
| } |
| } |
| } |
| |
| if (FLAG_cleanup_code_caches_at_gc) { |
| PolymorphicCodeCache* poly_cache = heap_->polymorphic_code_cache(); |
| Marking::GreyToBlack(Marking::MarkBitFrom(poly_cache)); |
| MemoryChunk::IncrementLiveBytesFromGC(poly_cache, |
| PolymorphicCodeCache::kSize); |
| } |
| |
| Object* context = heap_->native_contexts_list(); |
| while (!context->IsUndefined()) { |
| // GC can happen when the context is not fully initialized, |
| // so the cache can be undefined. |
| HeapObject* cache = HeapObject::cast( |
| Context::cast(context)->get(Context::NORMALIZED_MAP_CACHE_INDEX)); |
| if (!cache->IsUndefined()) { |
| MarkBit mark_bit = Marking::MarkBitFrom(cache); |
| if (Marking::IsGrey(mark_bit)) { |
| Marking::GreyToBlack(mark_bit); |
| MemoryChunk::IncrementLiveBytesFromGC(cache, cache->Size()); |
| } |
| } |
| context = Context::cast(context)->get(Context::NEXT_CONTEXT_LINK); |
| } |
| } |
| |
| |
| void IncrementalMarking::Stop() { |
| if (IsStopped()) return; |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Stopping.\n"); |
| } |
| |
| heap_->new_space()->RemoveAllocationObserver(&observer_); |
| IncrementalMarking::set_should_hurry(false); |
| ResetStepCounters(); |
| if (IsMarking()) { |
| PatchIncrementalMarkingRecordWriteStubs(heap_, |
| RecordWriteStub::STORE_BUFFER_ONLY); |
| DeactivateIncrementalWriteBarrier(); |
| } |
| heap_->isolate()->stack_guard()->ClearGC(); |
| state_ = STOPPED; |
| is_compacting_ = false; |
| } |
| |
| |
| void IncrementalMarking::Finalize() { |
| Hurry(); |
| Stop(); |
| } |
| |
| |
| void IncrementalMarking::FinalizeMarking(CompletionAction action) { |
| DCHECK(!finalize_marking_completed_); |
| if (FLAG_trace_incremental_marking) { |
| PrintF( |
| "[IncrementalMarking] requesting finalization of incremental " |
| "marking.\n"); |
| } |
| request_type_ = FINALIZATION; |
| if (action == GC_VIA_STACK_GUARD) { |
| heap_->isolate()->stack_guard()->RequestGC(); |
| } |
| } |
| |
| |
| void IncrementalMarking::MarkingComplete(CompletionAction action) { |
| state_ = COMPLETE; |
| // We will set the stack guard to request a GC now. This will mean the rest |
| // of the GC gets performed as soon as possible (we can't do a GC here in a |
| // record-write context). If a few things get allocated between now and then |
| // that shouldn't make us do a scavenge and keep being incremental, so we set |
| // the should-hurry flag to indicate that there can't be much work left to do. |
| set_should_hurry(true); |
| if (FLAG_trace_incremental_marking) { |
| PrintF("[IncrementalMarking] Complete (normal).\n"); |
| } |
| request_type_ = COMPLETE_MARKING; |
| if (action == GC_VIA_STACK_GUARD) { |
| heap_->isolate()->stack_guard()->RequestGC(); |
| } |
| } |
| |
| |
| void IncrementalMarking::Epilogue() { |
| was_activated_ = false; |
| finalize_marking_completed_ = false; |
| incremental_marking_finalization_rounds_ = 0; |
| } |
| |
| |
| double IncrementalMarking::AdvanceIncrementalMarking( |
| intptr_t step_size_in_bytes, double deadline_in_ms, |
| IncrementalMarking::StepActions step_actions) { |
| DCHECK(!IsStopped()); |
| |
| if (step_size_in_bytes == 0) { |
| step_size_in_bytes = GCIdleTimeHandler::EstimateMarkingStepSize( |
| static_cast<size_t>(GCIdleTimeHandler::kIncrementalMarkingStepTimeInMs), |
| static_cast<size_t>( |
| heap() |
| ->tracer() |
| ->FinalIncrementalMarkCompactSpeedInBytesPerMillisecond())); |
| } |
| |
| double remaining_time_in_ms = 0.0; |
| do { |
| Step(step_size_in_bytes, step_actions.completion_action, |
| step_actions.force_marking, step_actions.force_completion); |
| remaining_time_in_ms = |
| deadline_in_ms - heap()->MonotonicallyIncreasingTimeInMs(); |
| } while (remaining_time_in_ms >= |
| 2.0 * GCIdleTimeHandler::kIncrementalMarkingStepTimeInMs && |
| !IsComplete() && |
| !heap()->mark_compact_collector()->marking_deque()->IsEmpty()); |
| return remaining_time_in_ms; |
| } |
| |
| |
| void IncrementalMarking::OldSpaceStep(intptr_t allocated) { |
| if (IsStopped() && ShouldActivateEvenWithoutIdleNotification()) { |
| heap()->StartIncrementalMarking(Heap::kNoGCFlags, kNoGCCallbackFlags, |
| "old space step"); |
| } else { |
| Step(allocated * kFastMarking / kInitialMarkingSpeed, GC_VIA_STACK_GUARD); |
| } |
| } |
| |
| |
| void IncrementalMarking::SpeedUp() { |
| bool speed_up = false; |
| |
| if ((steps_count_ % kMarkingSpeedAccellerationInterval) == 0) { |
| if (FLAG_trace_incremental_marking) { |
| PrintIsolate(heap()->isolate(), "Speed up marking after %d steps\n", |
| static_cast<int>(kMarkingSpeedAccellerationInterval)); |
| } |
| speed_up = true; |
| } |
| |
| bool space_left_is_very_small = |
| (old_generation_space_available_at_start_of_incremental_ < 10 * MB); |
| |
| bool only_1_nth_of_space_that_was_available_still_left = |
| (SpaceLeftInOldSpace() * (marking_speed_ + 1) < |
| old_generation_space_available_at_start_of_incremental_); |
| |
| if (space_left_is_very_small || |
| only_1_nth_of_space_that_was_available_still_left) { |
| if (FLAG_trace_incremental_marking) |
| PrintIsolate(heap()->isolate(), |
| "Speed up marking because of low space left\n"); |
| speed_up = true; |
| } |
| |
| bool size_of_old_space_multiplied_by_n_during_marking = |
| (heap_->PromotedTotalSize() > |
| (marking_speed_ + 1) * |
| old_generation_space_used_at_start_of_incremental_); |
| if (size_of_old_space_multiplied_by_n_during_marking) { |
| speed_up = true; |
| if (FLAG_trace_incremental_marking) { |
| PrintIsolate(heap()->isolate(), |
| "Speed up marking because of heap size increase\n"); |
| } |
| } |
| |
| int64_t promoted_during_marking = |
| heap_->PromotedTotalSize() - |
| old_generation_space_used_at_start_of_incremental_; |
| intptr_t delay = marking_speed_ * MB; |
| intptr_t scavenge_slack = heap_->MaxSemiSpaceSize(); |
| |
| // We try to scan at at least twice the speed that we are allocating. |
| if (promoted_during_marking > bytes_scanned_ / 2 + scavenge_slack + delay) { |
| if (FLAG_trace_incremental_marking) { |
| PrintIsolate(heap()->isolate(), |
| "Speed up marking because marker was not keeping up\n"); |
| } |
| speed_up = true; |
| } |
| |
| if (speed_up) { |
| if (state_ != MARKING) { |
| if (FLAG_trace_incremental_marking) { |
| PrintIsolate(heap()->isolate(), |
| "Postponing speeding up marking until marking starts\n"); |
| } |
| } else { |
| marking_speed_ += kMarkingSpeedAccelleration; |
| marking_speed_ = static_cast<int>( |
| Min(kMaxMarkingSpeed, static_cast<intptr_t>(marking_speed_ * 1.3))); |
| if (FLAG_trace_incremental_marking) { |
| PrintIsolate(heap()->isolate(), "Marking speed increased to %d\n", |
| marking_speed_); |
| } |
| } |
| } |
| } |
| |
| |
| intptr_t IncrementalMarking::Step(intptr_t allocated_bytes, |
| CompletionAction action, |
| ForceMarkingAction marking, |
| ForceCompletionAction completion) { |
| DCHECK(allocated_bytes >= 0); |
| |
| if (heap_->gc_state() != Heap::NOT_IN_GC || !FLAG_incremental_marking || |
| (state_ != SWEEPING && state_ != MARKING)) { |
| return 0; |
| } |
| |
| allocated_ += allocated_bytes; |
| |
| if (marking == DO_NOT_FORCE_MARKING && allocated_ < kAllocatedThreshold && |
| write_barriers_invoked_since_last_step_ < |
| kWriteBarriersInvokedThreshold) { |
| return 0; |
| } |
| |
| // If an idle notification happened recently, we delay marking steps. |
| if (marking == DO_NOT_FORCE_MARKING && |
| heap_->RecentIdleNotificationHappened()) { |
| return 0; |
| } |
| |
| if (state_ == MARKING && no_marking_scope_depth_ > 0) return 0; |
| |
| intptr_t bytes_processed = 0; |
| { |
| HistogramTimerScope incremental_marking_scope( |
| heap_->isolate()->counters()->gc_incremental_marking()); |
| TRACE_EVENT0("v8", "V8.GCIncrementalMarking"); |
| double start = heap_->MonotonicallyIncreasingTimeInMs(); |
| |
| // The marking speed is driven either by the allocation rate or by the rate |
| // at which we are having to check the color of objects in the write |
| // barrier. |
| // It is possible for a tight non-allocating loop to run a lot of write |
| // barriers before we get here and check them (marking can only take place |
| // on |
| // allocation), so to reduce the lumpiness we don't use the write barriers |
| // invoked since last step directly to determine the amount of work to do. |
| intptr_t bytes_to_process = |
| marking_speed_ * |
| Max(allocated_, write_barriers_invoked_since_last_step_); |
| allocated_ = 0; |
| write_barriers_invoked_since_last_step_ = 0; |
| |
| bytes_scanned_ += bytes_to_process; |
| |
| if (state_ == SWEEPING) { |
| if (heap_->mark_compact_collector()->sweeping_in_progress() && |
| (heap_->mark_compact_collector()->IsSweepingCompleted() || |
| !FLAG_concurrent_sweeping)) { |
| heap_->mark_compact_collector()->EnsureSweepingCompleted(); |
| } |
| if (!heap_->mark_compact_collector()->sweeping_in_progress()) { |
| bytes_scanned_ = 0; |
| StartMarking(); |
| } |
| } else if (state_ == MARKING) { |
| bytes_processed = ProcessMarkingDeque(bytes_to_process); |
| if (heap_->mark_compact_collector()->marking_deque()->IsEmpty()) { |
| if (completion == FORCE_COMPLETION || |
| IsIdleMarkingDelayCounterLimitReached()) { |
| if (!finalize_marking_completed_) { |
| FinalizeMarking(action); |
| } else { |
| MarkingComplete(action); |
| } |
| } else { |
| IncrementIdleMarkingDelayCounter(); |
| } |
| } |
| } |
| |
| steps_count_++; |
| |
| // Speed up marking if we are marking too slow or if we are almost done |
| // with marking. |
| SpeedUp(); |
| |
| double end = heap_->MonotonicallyIncreasingTimeInMs(); |
| double duration = (end - start); |
| // Note that we report zero bytes here when sweeping was in progress or |
| // when we just started incremental marking. In these cases we did not |
| // process the marking deque. |
| heap_->tracer()->AddIncrementalMarkingStep(duration, bytes_processed); |
| } |
| return bytes_processed; |
| } |
| |
| |
| void IncrementalMarking::ResetStepCounters() { |
| steps_count_ = 0; |
| old_generation_space_available_at_start_of_incremental_ = |
| SpaceLeftInOldSpace(); |
| old_generation_space_used_at_start_of_incremental_ = |
| heap_->PromotedTotalSize(); |
| bytes_rescanned_ = 0; |
| marking_speed_ = kInitialMarkingSpeed; |
| bytes_scanned_ = 0; |
| write_barriers_invoked_since_last_step_ = 0; |
| } |
| |
| |
| int64_t IncrementalMarking::SpaceLeftInOldSpace() { |
| return heap_->MaxOldGenerationSize() - heap_->PromotedSpaceSizeOfObjects(); |
| } |
| |
| |
| bool IncrementalMarking::IsIdleMarkingDelayCounterLimitReached() { |
| return idle_marking_delay_counter_ > kMaxIdleMarkingDelayCounter; |
| } |
| |
| |
| void IncrementalMarking::IncrementIdleMarkingDelayCounter() { |
| idle_marking_delay_counter_++; |
| } |
| |
| |
| void IncrementalMarking::ClearIdleMarkingDelayCounter() { |
| idle_marking_delay_counter_ = 0; |
| } |
| } // namespace internal |
| } // namespace v8 |