The time spent in GCPrologue callbacks and GCEpilogue callbacks should be measured as EXTERNAL time

src/heap.cc

 // Copyright 2012 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 851 matching lines @@
 
   if (collector == MARK_COMPACTOR && global_gc_prologue_callback_) {
     ASSERT(!allocation_allowed_);
     GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
     global_gc_prologue_callback_();
   }
 
   GCType gc_type =
       collector == MARK_COMPACTOR ? kGCTypeMarkSweepCompact : kGCTypeScavenge;
 
-  for (int i = 0; i < gc_prologue_callbacks_.length(); ++i) {
-    if (gc_type & gc_prologue_callbacks_[i].gc_type) {
-      gc_prologue_callbacks_[i].callback(gc_type, kNoGCCallbackFlags);
+  {
+    GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
+    for (int i = 0; i < gc_prologue_callbacks_.length(); ++i) {
+      if (gc_type & gc_prologue_callbacks_[i].gc_type) {
+        gc_prologue_callbacks_[i].callback(gc_type, kNoGCCallbackFlags);
+      }
     }
   }
 
   EnsureFromSpaceIsCommitted();
 
   int start_new_space_size = Heap::new_space()->SizeAsInt();
 
   if (IsHighSurvivalRate()) {
     // We speed up the incremental marker if it is running so that it
     // does not fall behind the rate of promotion, which would cause a
@@ skipping 87 matching lines @@
 
   // Update relocatables.
   Relocatable::PostGarbageCollectionProcessing();
 
   if (collector == MARK_COMPACTOR) {
     // Register the amount of external allocated memory.
     amount_of_external_allocated_memory_at_last_global_gc_ =
         amount_of_external_allocated_memory_;
   }
 
-  GCCallbackFlags callback_flags = kNoGCCallbackFlags;
-  for (int i = 0; i < gc_epilogue_callbacks_.length(); ++i) {
-    if (gc_type & gc_epilogue_callbacks_[i].gc_type) {
-      gc_epilogue_callbacks_[i].callback(gc_type, callback_flags);
+  {
+    GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
+    GCCallbackFlags callback_flags = kNoGCCallbackFlags;
+    for (int i = 0; i < gc_epilogue_callbacks_.length(); ++i) {
+      if (gc_type & gc_epilogue_callbacks_[i].gc_type) {
+        gc_epilogue_callbacks_[i].callback(gc_type, callback_flags);
+      }
     }
   }
 
   if (collector == MARK_COMPACTOR && global_gc_epilogue_callback_) {
     ASSERT(!allocation_allowed_);
     GCTracer::Scope scope(tracer, GCTracer::Scope::EXTERNAL);
     global_gc_epilogue_callback_();
   }
 
 #ifdef VERIFY_HEAP
@@ skipping 6360 matching lines @@
       static_cast<int>(object_sizes_last_time_[index]));
   FIXED_ARRAY_SUB_INSTANCE_TYPE_LIST(ADJUST_LAST_TIME_OBJECT_COUNT)
 #undef ADJUST_LAST_TIME_OBJECT_COUNT
 
   memcpy(object_counts_last_time_, object_counts_, sizeof(object_counts_));
   memcpy(object_sizes_last_time_, object_sizes_, sizeof(object_sizes_));
   ClearObjectStats();
 }
 
 } }  // namespace v8::internal