[api] Add an API function to set the GetExternallyAllocatedMemoryInBytesCallback.

src/heap/heap.cc

 // 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/heap.h"
 
 #include <unordered_map>
 #include <unordered_set>
 
 #include "src/accessors.h"
@@ skipping 363 matching lines @@
                lo_space_->CommittedMemory() / KB);
   PrintIsolate(isolate_, "All spaces,         used: %6" PRIuS
                          " KB"
                          ", available: %6" PRIuS
                          " KB"
                          ", committed: %6" PRIuS "KB\n",
                this->SizeOfObjects() / KB, this->Available() / KB,
                this->CommittedMemory() / KB);
   PrintIsolate(isolate_, "External memory reported: %6" PRId64 " KB\n",
                external_memory_ / KB);
+  PrintIsolate(isolate_, "External memory global %zu KB\n",
+               external_memory_callback_() / KB);
   PrintIsolate(isolate_, "Total time spent in GC  : %.1f ms\n",
                total_gc_time_ms_);
 }
 
 // TODO(1238405): Combine the infrastructure for --heap-stats and
 // --log-gc to avoid the complicated preprocessor and flag testing.
 void Heap::ReportStatisticsAfterGC() {
 // Similar to the before GC, we use some complicated logic to ensure that
 // NewSpace statistics are logged exactly once when --log-gc is turned on.
 #if defined(DEBUG)
@@ skipping 563 matching lines @@
     DCHECK_GE(1, pressure);
     const double kMaxStepSizeOnExternalLimit = 25;
     const double deadline = MonotonicallyIncreasingTimeInMs() +
                             pressure * kMaxStepSizeOnExternalLimit;
     incremental_marking()->AdvanceIncrementalMarking(
         deadline, IncrementalMarking::GC_VIA_STACK_GUARD,
         IncrementalMarking::FORCE_COMPLETION, StepOrigin::kV8);
   }
 }
 
-
 void Heap::EnsureFillerObjectAtTop() {
   // There may be an allocation memento behind objects in new space. Upon
   // evacuation of a non-full new space (or if we are on the last page) there
   // may be uninitialized memory behind top. We fill the remainder of the page
   // with a filler.
   Address to_top = new_space_->top();
   Page* page = Page::FromAddress(to_top - kPointerSize);
   if (page->Contains(to_top)) {
     int remaining_in_page = static_cast<int>(page->area_end() - to_top);
     CreateFillerObjectAt(to_top, remaining_in_page, ClearRecordedSlots::kNo);
@@ skipping 4754 matching lines @@
 
   mark_compact_collector()->SetUp();
   if (minor_mark_compact_collector() != nullptr) {
     minor_mark_compact_collector()->SetUp();
   }
 
   idle_scavenge_observer_ = new IdleScavengeObserver(
       *this, ScavengeJob::kBytesAllocatedBeforeNextIdleTask);
   new_space()->AddAllocationObserver(idle_scavenge_observer_);
 
+  SetGetExternallyAllocatedMemoryInBytesCallback(
+      DefaultGetExternallyAllocatedMemoryInBytesCallback);
+
   return true;
 }
 
 
 bool Heap::CreateHeapObjects() {
   // Create initial maps.
   if (!CreateInitialMaps()) return false;
   if (!CreateApiObjects()) return false;
 
   // Create initial objects
@@ skipping 852 matching lines @@
     case LO_SPACE:
       return "LO_SPACE";
     default:
       UNREACHABLE();
   }
   return NULL;
 }
 
 }  // namespace internal
 }  // namespace v8