Allow Oilpan heap objects account for their external allocations.

Source/platform/heap/Heap.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 972 matching lines @@
     }
 
     static void increaseAllocatedObjectSize(size_t delta) { atomicAdd(&s_allocatedObjectSize, static_cast<long>(delta)); }
     static void decreaseAllocatedObjectSize(size_t delta) { atomicSubtract(&s_allocatedObjectSize, static_cast<long>(delta)); }
     static size_t allocatedObjectSize() { return acquireLoad(&s_allocatedObjectSize); }
     static void increaseMarkedObjectSize(size_t delta) { atomicAdd(&s_markedObjectSize, static_cast<long>(delta)); }
     static size_t markedObjectSize() { return acquireLoad(&s_markedObjectSize); }
     static void increaseAllocatedSpace(size_t delta) { atomicAdd(&s_allocatedSpace, static_cast<long>(delta)); }
     static void decreaseAllocatedSpace(size_t delta) { atomicSubtract(&s_allocatedSpace, static_cast<long>(delta)); }
     static size_t allocatedSpace() { return acquireLoad(&s_allocatedSpace); }
+
     static double estimatedMarkingTime();
 
+    // On object allocation, register the object's externally allocated memory.
+    static inline void increaseExternallyAllocatedBytes(size_t);
+    static size_t externallyAllocatedBytes() { return acquireLoad(&s_externallyAllocatedBytes); }
+
+    // On object tracing, register the object's externally allocated memory (as still live.)
+    static void increaseExternallyAllocatedBytesAlive(size_t delta)
+    {
+        ASSERT(ThreadState::current()->isInGC());
+        s_externallyAllocatedBytesAlive += delta;
+    }
+    static size_t externallyAllocatedBytesAlive() { return s_externallyAllocatedBytesAlive; }
+
+    static void requestUrgentGC();
+    static void clearUrgentGC() { releaseStore(&s_requestedUrgentGC, 0); }
+    static bool isUrgentGCRequested() { return acquireLoad(&s_requestedUrgentGC); }
+
 private:
     // A RegionTree is a simple binary search tree of PageMemoryRegions sorted
     // by base addresses.
     class RegionTree {
     public:
         explicit RegionTree(PageMemoryRegion* region) : m_region(region), m_left(nullptr), m_right(nullptr) { }
         ~RegionTree()
         {
             delete m_left;
             delete m_right;
         }
         PageMemoryRegion* lookup(Address);
         static void add(RegionTree*, RegionTree**);
         static void remove(PageMemoryRegion*, RegionTree**);
     private:
         PageMemoryRegion* m_region;
         RegionTree* m_left;
         RegionTree* m_right;
     };
 
-    static void resetAllocatedObjectSize() { ASSERT(ThreadState::current()->isInGC()); s_allocatedObjectSize = 0; }
-    static void resetMarkedObjectSize() { ASSERT(ThreadState::current()->isInGC()); s_markedObjectSize = 0; }
+    // Reset counters that track live and allocated-since-last-GC sizes.
+    static void resetHeapCounters();
 
     static Visitor* s_markingVisitor;
     static CallbackStack* s_markingStack;
     static CallbackStack* s_postMarkingCallbackStack;
     static CallbackStack* s_weakCallbackStack;
     static CallbackStack* s_ephemeronStack;
     static HeapDoesNotContainCache* s_heapDoesNotContainCache;
     static bool s_shutdownCalled;
     static bool s_lastGCWasConservative;
     static FreePagePool* s_freePagePool;
     static OrphanedPagePool* s_orphanedPagePool;
     static RegionTree* s_regionTree;
     static size_t s_allocatedSpace;
     static size_t s_allocatedObjectSize;
     static size_t s_markedObjectSize;
+    static size_t s_externallyAllocatedBytes;
+    static size_t s_externallyAllocatedBytesAlive;
+    static unsigned s_requestedUrgentGC;
+
     friend class ThreadState;
 };
 
 // Base class for objects allocated in the Blink garbage-collected heap.
 //
 // Defines a 'new' operator that allocates the memory in the heap.  'delete'
 // should not be called on objects that inherit from GarbageCollected.
 //
 // Instances of GarbageCollected will *NOT* get finalized.  Their destructor
 // will not be called.  Therefore, only classes that have trivial destructors
@@ skipping 379 matching lines @@
     // FIXME: We don't support reallocate() for finalizable objects.
     ASSERT(!Heap::gcInfo(previousHeader->gcInfoIndex())->hasFinalizer());
     ASSERT(previousHeader->gcInfoIndex() == GCInfoTrait<T>::index());
     size_t copySize = previousHeader->payloadSize();
     if (copySize > size)
         copySize = size;
     memcpy(address, previous, copySize);
     return address;
 }
 
+void Heap::increaseExternallyAllocatedBytes(size_t delta)
+{
+    size_t externalBytesAllocatedSinceLastGC = atomicAdd(&s_externallyAllocatedBytes, static_cast<long>(delta));
+
+    if (UNLIKELY(isUrgentGCRequested()))

[haraken, 2015/02/23 08:42:27]

Can we move this check down to line 1469? For performance it seems better to
check LIKELY(externalBytesAllocatedSinceLastGC < ...) first.

[sof, 2015/02/23 12:26:13]

Done.

+        return;
+
+    // Flag GC urgency on a 50% increase in external allocation
+    // since the last GC, but not for less than 100M.
+    //
+    // FIXME: consider other, 'better' policies (e.g., have the count of
+    // heap objects with external allocations be taken into
+    // account, ...) The overall goal here is to trigger a
+    // GC such that it considerably lessens memory pressure
+    // for a renderer process, when absolutely needed.
+    if (LIKELY(externalBytesAllocatedSinceLastGC < 100 * 1024 * 1024))
+        return;
+
+    size_t externalBytesAliveAtLastGC = externallyAllocatedBytesAlive();
+    if (UNLIKELY(externalBytesAllocatedSinceLastGC > externalBytesAliveAtLastGC / 2))
+        Heap::requestUrgentGC();
+}
+
 class HeapAllocatorQuantizer {
 public:
     template<typename T>
     static size_t quantizedSize(size_t count)
     {
         RELEASE_ASSERT(count <= kMaxUnquantizedAllocation / sizeof(T));
         return BaseHeap::roundedAllocationSize(count * sizeof(T));
     }
     static const size_t kMaxUnquantizedAllocation = maxHeapObjectSize;
 };
@@ skipping 1001 matching lines @@
 template<typename T, size_t inlineCapacity>
 struct GCInfoTrait<HeapVector<T, inlineCapacity>> : public GCInfoTrait<Vector<T, inlineCapacity, HeapAllocator>> { };
 template<typename T, size_t inlineCapacity>
 struct GCInfoTrait<HeapDeque<T, inlineCapacity>> : public GCInfoTrait<Deque<T, inlineCapacity, HeapAllocator>> { };
 template<typename T, typename U, typename V>
 struct GCInfoTrait<HeapHashCountedSet<T, U, V>> : public GCInfoTrait<HashCountedSet<T, U, V, HeapAllocator>> { };
 
 } // namespace blink
 
 #endif // Heap_h