content/shell/renderer/gc_controller.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/shell/renderer/gc_controller.h"
   6
   7 #include "gin/arguments.h"
   8 #include "gin/handle.h"
   9 #include "gin/object_template_builder.h"
  10 #include "third_party/WebKit/public/web/WebFrame.h"
  11 #include "third_party/WebKit/public/web/WebKit.h"
  12 #include "v8/include/v8.h"
  13
  14 namespace content {
  15
  16 gin::WrapperInfo GCController::kWrapperInfo = {gin::kEmbedderNativeGin};
  17
  18 // static
  19 void GCController::Install(blink::WebFrame* frame) {
  20   v8::Isolate* isolate = blink::mainThreadIsolate();
  21   v8::HandleScope handle_scope(isolate);
  22   v8::Handle<v8::Context> context = frame->mainWorldScriptContext();
  23   if (context.IsEmpty())
  24     return;
  25
  26   v8::Context::Scope context_scope(context);
  27
  28   gin::Handle<GCController> controller =
  29       gin::CreateHandle(isolate, new GCController());
  30   v8::Handle<v8::Object> global = context->Global();
  31   global->Set(gin::StringToV8(isolate, "GCController"), controller.ToV8());
  32 }
  33
  34 GCController::GCController() {}
  35
  36 GCController::~GCController() {}
  37
  38 gin::ObjectTemplateBuilder GCController::GetObjectTemplateBuilder(
  39     v8::Isolate* isolate) {
  40   return gin::Wrappable<GCController>::GetObjectTemplateBuilder(isolate)
  41       .SetMethod("collect", &GCController::Collect)
  42       .SetMethod("collectAll", &GCController::CollectAll)
  43       .SetMethod("minorCollect", &GCController::MinorCollect);
  44 }
  45
  46 void GCController::Collect(const gin::Arguments& args) {
  47   args.isolate()->RequestGarbageCollectionForTesting(
  48       v8::Isolate::kFullGarbageCollection);
  49 }
  50
  51 void GCController::CollectAll(const gin::Arguments& args) {
  52   // In order to collect a DOM wrapper, two GC cycles are needed.
  53   // In the first GC cycle, a weak callback of the DOM wrapper is called back
  54   // and the weak callback disposes a persistent handle to the DOM wrapper.
  55   // In the second GC cycle, the DOM wrapper is reclaimed.
  56   // Given that two GC cycles are needed to collect one DOM wrapper,
  57   // more than two GC cycles are needed to collect all DOM wrappers
  58   // that are chained. Seven GC cycles look enough in most tests.
  59   for (int i = 0; i < 7; i++) {
  60     args.isolate()->RequestGarbageCollectionForTesting(
  61         v8::Isolate::kFullGarbageCollection);
  62   }
  63 }
  64
  65 void GCController::MinorCollect(const gin::Arguments& args) {
  66   args.isolate()->RequestGarbageCollectionForTesting(
  67       v8::Isolate::kMinorGarbageCollection);
  68 }
  69
  70 }  // namespace content