[heap] Pause black allocation during GCs

src/heap/incremental-marking.h

 // 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.
 
 #ifndef V8_HEAP_INCREMENTAL_MARKING_H_
 #define V8_HEAP_INCREMENTAL_MARKING_H_
 
 #include "src/cancelable-task.h"
 #include "src/execution.h"
 #include "src/heap/heap.h"
@@ skipping 14 matching lines @@
 class V8_EXPORT_PRIVATE IncrementalMarking {
  public:
   enum State { STOPPED, SWEEPING, MARKING, COMPLETE };
 
   enum CompletionAction { GC_VIA_STACK_GUARD, NO_GC_VIA_STACK_GUARD };
 
   enum ForceCompletionAction { FORCE_COMPLETION, DO_NOT_FORCE_COMPLETION };
 
   enum GCRequestType { NONE, COMPLETE_MARKING, FINALIZATION };
 
+  class PauseBlackAllocationScope {
+   public:
+    explicit PauseBlackAllocationScope(IncrementalMarking* marking)
+        : marking_(marking), paused_(false) {
+      if (marking_->black_allocation()) {
+        paused_ = true;
+        marking_->PauseBlackAllocation();
+      }
+    }
+
+    ~PauseBlackAllocationScope() {
+      if (paused_) {
+        marking_->StartBlackAllocation();
+      }
+    }
+
+   private:
+    IncrementalMarking* marking_;
+    bool paused_;
+  };
+
   static void Initialize();
 
   explicit IncrementalMarking(Heap* heap);
 
   MarkingState marking_state(HeapObject* object) const {
     return MarkingState::Internal(object);
   }
 
   MarkingState marking_state(MemoryChunk* chunk) const {
     return MarkingState::Internal(chunk);
@@ skipping 202 matching lines @@
 
    private:
     IncrementalMarking& incremental_marking_;
   };
 
   int64_t SpaceLeftInOldSpace();
 
   void StartMarking();
 
   void StartBlackAllocation();
+  void PauseBlackAllocation();
   void FinishBlackAllocation();
 
   void MarkRoots();
   void ProcessWeakCells();
   // Retain dying maps for <FLAG_retain_maps_for_n_gc> garbage collections to
   // increase chances of reusing of map transition tree in future.
   void RetainMaps();
 
   void ActivateIncrementalWriteBarrier(PagedSpace* space);
   static void ActivateIncrementalWriteBarrier(NewSpace* space);
@@ skipping 50 matching lines @@
 
   Observer new_generation_observer_;
   Observer old_generation_observer_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(IncrementalMarking);
 };
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_INCREMENTAL_MARKING_H_