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
14namespace content {
15
16gin::WrapperInfo GCController::kWrapperInfo = {gin::kEmbedderNativeGin};
17
18// static
19void 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  if (controller.IsEmpty())
31    return;
32  v8::Handle<v8::Object> global = context->Global();
33  global->Set(gin::StringToV8(isolate, "GCController"), controller.ToV8());
34}
35
36GCController::GCController() {}
37
38GCController::~GCController() {}
39
40gin::ObjectTemplateBuilder GCController::GetObjectTemplateBuilder(
41    v8::Isolate* isolate) {
42  return gin::Wrappable<GCController>::GetObjectTemplateBuilder(isolate)
43      .SetMethod("collect", &GCController::Collect)
44      .SetMethod("collectAll", &GCController::CollectAll)
45      .SetMethod("minorCollect", &GCController::MinorCollect);
46}
47
48void GCController::Collect(const gin::Arguments& args) {
49  args.isolate()->RequestGarbageCollectionForTesting(
50      v8::Isolate::kFullGarbageCollection);
51}
52
53void GCController::CollectAll(const gin::Arguments& args) {
54  // In order to collect a DOM wrapper, two GC cycles are needed.
55  // In the first GC cycle, a weak callback of the DOM wrapper is called back
56  // and the weak callback disposes a persistent handle to the DOM wrapper.
57  // In the second GC cycle, the DOM wrapper is reclaimed.
58  // Given that two GC cycles are needed to collect one DOM wrapper,
59  // more than two GC cycles are needed to collect all DOM wrappers
60  // that are chained. Seven GC cycles look enough in most tests.
61  for (int i = 0; i < 7; i++) {
62    args.isolate()->RequestGarbageCollectionForTesting(
63        v8::Isolate::kFullGarbageCollection);
64  }
65}
66
67void GCController::MinorCollect(const gin::Arguments& args) {
68  args.isolate()->RequestGarbageCollectionForTesting(
69      v8::Isolate::kMinorGarbageCollection);
70}
71
72}  // namespace content
73