v8/test/cctest/test-global-handles.cc
ulan a6da98d86f Introduce a new phantom weakness type without finalization callback.
Handles of this type are automatically reset by the garbage collector
when their objects are not longer reachable.

The motivation is to reduce pause time of external.weak_global_handles
phase of the garbage collector by not maintaing the list of pending
callbacks and not calling the callbacks.

Local testing on discourse page of the v8.inifinite_scroll benchmark
shows 7x improvement for this GC phase.

Before:
external.weak_global_handles
 len: 21
 min: 0.0
 max: 4.5
 avg: 0.757142857143

After:
external.weak_global_handles
 len: 21
 min: 0.0
 max: 0.5
 avg: 0.109523809524

A follow-up patch will enable the new phantom handles in Chromium.

BUG=chromium:608333
LOG=NO

Review-Url: https://codereview.chromium.org/1950963002
Cr-Commit-Position: refs/heads/master@{#36095}
2016-05-09 07:18:00 +00:00

472 lines
16 KiB
C++

// Copyright 2013 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
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "src/global-handles.h"
#include "test/cctest/cctest.h"
using namespace v8::internal;
using v8::UniqueId;
static List<Object*> skippable_objects;
static List<Object*> can_skip_called_objects;
static bool CanSkipCallback(Heap* heap, Object** pointer) {
can_skip_called_objects.Add(*pointer);
return skippable_objects.Contains(*pointer);
}
static void ResetCanSkipData() {
skippable_objects.Clear();
can_skip_called_objects.Clear();
}
class TestRetainedObjectInfo : public v8::RetainedObjectInfo {
public:
TestRetainedObjectInfo() : has_been_disposed_(false) {}
bool has_been_disposed() { return has_been_disposed_; }
virtual void Dispose() {
CHECK(!has_been_disposed_);
has_been_disposed_ = true;
}
virtual bool IsEquivalent(v8::RetainedObjectInfo* other) {
return other == this;
}
virtual intptr_t GetHash() { return 0; }
virtual const char* GetLabel() { return "whatever"; }
private:
bool has_been_disposed_;
};
class TestObjectVisitor : public ObjectVisitor {
public:
void VisitPointers(Object** start, Object** end) override {
for (Object** o = start; o != end; ++o)
visited.Add(*o);
}
List<Object*> visited;
};
TEST(IterateObjectGroupsOldApi) {
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
GlobalHandles* global_handles = isolate->global_handles();
v8::HandleScope handle_scope(CcTest::isolate());
Handle<Object> g1s1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g1s2 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2s1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2s2 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
TestRetainedObjectInfo info1;
TestRetainedObjectInfo info2;
{
Object** g1_objects[] = { g1s1.location(), g1s2.location() };
Object** g2_objects[] = { g2s1.location(), g2s2.location() };
global_handles->AddObjectGroup(g1_objects, 2, &info1);
global_handles->AddObjectGroup(g2_objects, 2, &info2);
}
// Iterate the object groups. First skip all.
{
ResetCanSkipData();
skippable_objects.Add(*g1s1.location());
skippable_objects.Add(*g1s2.location());
skippable_objects.Add(*g2s1.location());
skippable_objects.Add(*g2s2.location());
TestObjectVisitor visitor;
global_handles->IterateObjectGroups(&visitor, &CanSkipCallback);
// CanSkipCallback was called for all objects.
CHECK(can_skip_called_objects.length() == 4);
CHECK(can_skip_called_objects.Contains(*g1s1.location()));
CHECK(can_skip_called_objects.Contains(*g1s2.location()));
CHECK(can_skip_called_objects.Contains(*g2s1.location()));
CHECK(can_skip_called_objects.Contains(*g2s2.location()));
// Nothing was visited.
CHECK(visitor.visited.length() == 0);
CHECK(!info1.has_been_disposed());
CHECK(!info2.has_been_disposed());
}
// Iterate again, now only skip the second object group.
{
ResetCanSkipData();
// The first grough should still be visited, since only one object is
// skipped.
skippable_objects.Add(*g1s1.location());
skippable_objects.Add(*g2s1.location());
skippable_objects.Add(*g2s2.location());
TestObjectVisitor visitor;
global_handles->IterateObjectGroups(&visitor, &CanSkipCallback);
// CanSkipCallback was called for all objects.
CHECK(can_skip_called_objects.length() == 3 ||
can_skip_called_objects.length() == 4);
CHECK(can_skip_called_objects.Contains(*g1s2.location()));
CHECK(can_skip_called_objects.Contains(*g2s1.location()));
CHECK(can_skip_called_objects.Contains(*g2s2.location()));
// The first group was visited.
CHECK(visitor.visited.length() == 2);
CHECK(visitor.visited.Contains(*g1s1.location()));
CHECK(visitor.visited.Contains(*g1s2.location()));
CHECK(info1.has_been_disposed());
CHECK(!info2.has_been_disposed());
}
// Iterate again, don't skip anything.
{
ResetCanSkipData();
TestObjectVisitor visitor;
global_handles->IterateObjectGroups(&visitor, &CanSkipCallback);
// CanSkipCallback was called for all objects.
CHECK(can_skip_called_objects.length() == 1);
CHECK(can_skip_called_objects.Contains(*g2s1.location()) ||
can_skip_called_objects.Contains(*g2s2.location()));
// The second group was visited.
CHECK(visitor.visited.length() == 2);
CHECK(visitor.visited.Contains(*g2s1.location()));
CHECK(visitor.visited.Contains(*g2s2.location()));
CHECK(info2.has_been_disposed());
}
}
TEST(IterateObjectGroups) {
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
GlobalHandles* global_handles = isolate->global_handles();
v8::HandleScope handle_scope(CcTest::isolate());
Handle<Object> g1s1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g1s2 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2s1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2s2 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
TestRetainedObjectInfo info1;
TestRetainedObjectInfo info2;
global_handles->SetObjectGroupId(g2s1.location(), UniqueId(2));
global_handles->SetObjectGroupId(g2s2.location(), UniqueId(2));
global_handles->SetRetainedObjectInfo(UniqueId(2), &info2);
global_handles->SetObjectGroupId(g1s1.location(), UniqueId(1));
global_handles->SetObjectGroupId(g1s2.location(), UniqueId(1));
global_handles->SetRetainedObjectInfo(UniqueId(1), &info1);
// Iterate the object groups. First skip all.
{
ResetCanSkipData();
skippable_objects.Add(*g1s1.location());
skippable_objects.Add(*g1s2.location());
skippable_objects.Add(*g2s1.location());
skippable_objects.Add(*g2s2.location());
TestObjectVisitor visitor;
global_handles->IterateObjectGroups(&visitor, &CanSkipCallback);
// CanSkipCallback was called for all objects.
CHECK(can_skip_called_objects.length() == 4);
CHECK(can_skip_called_objects.Contains(*g1s1.location()));
CHECK(can_skip_called_objects.Contains(*g1s2.location()));
CHECK(can_skip_called_objects.Contains(*g2s1.location()));
CHECK(can_skip_called_objects.Contains(*g2s2.location()));
// Nothing was visited.
CHECK(visitor.visited.length() == 0);
CHECK(!info1.has_been_disposed());
CHECK(!info2.has_been_disposed());
}
// Iterate again, now only skip the second object group.
{
ResetCanSkipData();
// The first grough should still be visited, since only one object is
// skipped.
skippable_objects.Add(*g1s1.location());
skippable_objects.Add(*g2s1.location());
skippable_objects.Add(*g2s2.location());
TestObjectVisitor visitor;
global_handles->IterateObjectGroups(&visitor, &CanSkipCallback);
// CanSkipCallback was called for all objects.
CHECK(can_skip_called_objects.length() == 3 ||
can_skip_called_objects.length() == 4);
CHECK(can_skip_called_objects.Contains(*g1s2.location()));
CHECK(can_skip_called_objects.Contains(*g2s1.location()));
CHECK(can_skip_called_objects.Contains(*g2s2.location()));
// The first group was visited.
CHECK(visitor.visited.length() == 2);
CHECK(visitor.visited.Contains(*g1s1.location()));
CHECK(visitor.visited.Contains(*g1s2.location()));
CHECK(info1.has_been_disposed());
CHECK(!info2.has_been_disposed());
}
// Iterate again, don't skip anything.
{
ResetCanSkipData();
TestObjectVisitor visitor;
global_handles->IterateObjectGroups(&visitor, &CanSkipCallback);
// CanSkipCallback was called for all objects.
CHECK(can_skip_called_objects.length() == 1);
CHECK(can_skip_called_objects.Contains(*g2s1.location()) ||
can_skip_called_objects.Contains(*g2s2.location()));
// The second group was visited.
CHECK(visitor.visited.length() == 2);
CHECK(visitor.visited.Contains(*g2s1.location()));
CHECK(visitor.visited.Contains(*g2s2.location()));
CHECK(info2.has_been_disposed());
}
}
TEST(ImplicitReferences) {
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
GlobalHandles* global_handles = isolate->global_handles();
v8::HandleScope handle_scope(CcTest::isolate());
Handle<Object> g1s1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g1c1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g1c2 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2s1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2s2 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
Handle<Object> g2c1 =
global_handles->Create(*isolate->factory()->NewFixedArray(1));
global_handles->SetObjectGroupId(g1s1.location(), UniqueId(1));
global_handles->SetObjectGroupId(g2s1.location(), UniqueId(2));
global_handles->SetObjectGroupId(g2s2.location(), UniqueId(2));
global_handles->SetReferenceFromGroup(UniqueId(1), g1c1.location());
global_handles->SetReferenceFromGroup(UniqueId(1), g1c2.location());
global_handles->SetReferenceFromGroup(UniqueId(2), g2c1.location());
List<ImplicitRefGroup*>* implicit_refs =
global_handles->implicit_ref_groups();
USE(implicit_refs);
CHECK(implicit_refs->length() == 2);
CHECK(implicit_refs->at(0)->parent ==
reinterpret_cast<HeapObject**>(g1s1.location()));
CHECK(implicit_refs->at(0)->length == 2);
CHECK(implicit_refs->at(0)->children[0] == g1c1.location());
CHECK(implicit_refs->at(0)->children[1] == g1c2.location());
CHECK(implicit_refs->at(1)->parent ==
reinterpret_cast<HeapObject**>(g2s1.location()));
CHECK(implicit_refs->at(1)->length == 1);
CHECK(implicit_refs->at(1)->children[0] == g2c1.location());
global_handles->RemoveObjectGroups();
global_handles->RemoveImplicitRefGroups();
}
TEST(EternalHandles) {
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
v8::Isolate* v8_isolate = reinterpret_cast<v8::Isolate*>(isolate);
EternalHandles* eternal_handles = isolate->eternal_handles();
// Create a number of handles that will not be on a block boundary
const int kArrayLength = 2048-1;
int indices[kArrayLength];
v8::Eternal<v8::Value> eternals[kArrayLength];
CHECK_EQ(0, eternal_handles->NumberOfHandles());
for (int i = 0; i < kArrayLength; i++) {
indices[i] = -1;
HandleScope scope(isolate);
v8::Local<v8::Object> object = v8::Object::New(v8_isolate);
object->Set(v8_isolate->GetCurrentContext(), i,
v8::Integer::New(v8_isolate, i))
.FromJust();
// Create with internal api
eternal_handles->Create(
isolate, *v8::Utils::OpenHandle(*object), &indices[i]);
// Create with external api
CHECK(eternals[i].IsEmpty());
eternals[i].Set(v8_isolate, object);
CHECK(!eternals[i].IsEmpty());
}
isolate->heap()->CollectAllAvailableGarbage();
for (int i = 0; i < kArrayLength; i++) {
for (int j = 0; j < 2; j++) {
HandleScope scope(isolate);
v8::Local<v8::Value> local;
if (j == 0) {
// Test internal api
local = v8::Utils::ToLocal(eternal_handles->Get(indices[i]));
} else {
// Test external api
local = eternals[i].Get(v8_isolate);
}
v8::Local<v8::Object> object = v8::Local<v8::Object>::Cast(local);
v8::Local<v8::Value> value =
object->Get(v8_isolate->GetCurrentContext(), i).ToLocalChecked();
CHECK(value->IsInt32());
CHECK_EQ(i,
value->Int32Value(v8_isolate->GetCurrentContext()).FromJust());
}
}
CHECK_EQ(2*kArrayLength, eternal_handles->NumberOfHandles());
// Create an eternal via the constructor
{
HandleScope scope(isolate);
v8::Local<v8::Object> object = v8::Object::New(v8_isolate);
v8::Eternal<v8::Object> eternal(v8_isolate, object);
CHECK(!eternal.IsEmpty());
CHECK(object == eternal.Get(v8_isolate));
}
CHECK_EQ(2*kArrayLength + 1, eternal_handles->NumberOfHandles());
}
TEST(PersistentBaseGetLocal) {
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
v8::Local<v8::Object> o = v8::Object::New(isolate);
CHECK(!o.IsEmpty());
v8::Persistent<v8::Object> p(isolate, o);
CHECK(o == p.Get(isolate));
CHECK(v8::Local<v8::Object>::New(isolate, p) == p.Get(isolate));
v8::Global<v8::Object> g(isolate, o);
CHECK(o == g.Get(isolate));
CHECK(v8::Local<v8::Object>::New(isolate, g) == g.Get(isolate));
}
void WeakCallback(const v8::WeakCallbackInfo<void>& data) {}
TEST(WeakPersistentSmi) {
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::HandleScope scope(isolate);
v8::Local<v8::Number> n = v8::Number::New(isolate, 0);
v8::Global<v8::Number> g(isolate, n);
// Should not crash.
g.SetWeak<void>(nullptr, &WeakCallback, v8::WeakCallbackType::kParameter);
}
void finalizer(const v8::WeakCallbackInfo<v8::Global<v8::Object>>& data) {
data.GetParameter()->ClearWeak();
v8::Local<v8::Object> o =
v8::Local<v8::Object>::New(data.GetIsolate(), *data.GetParameter());
o->Set(data.GetIsolate()->GetCurrentContext(), v8_str("finalizer"),
v8_str("was here"))
.FromJust();
}
TEST(FinalizerWeakness) {
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::Global<v8::Object> g;
int identity;
{
v8::HandleScope scope(isolate);
v8::Local<v8::Object> o = v8::Object::New(isolate);
identity = o->GetIdentityHash();
g.Reset(isolate, o);
g.SetWeak(&g, finalizer, v8::WeakCallbackType::kFinalizer);
}
CcTest::i_isolate()->heap()->CollectAllAvailableGarbage();
CHECK(!g.IsEmpty());
v8::HandleScope scope(isolate);
v8::Local<v8::Object> o = v8::Local<v8::Object>::New(isolate, g);
CHECK_EQ(identity, o->GetIdentityHash());
CHECK(o->Has(isolate->GetCurrentContext(), v8_str("finalizer")).FromJust());
}
TEST(PhatomHandlesWithoutCallbacks) {
CcTest::InitializeVM();
v8::Isolate* isolate = CcTest::isolate();
v8::Global<v8::Object> g1, g2;
{
v8::HandleScope scope(isolate);
g1.Reset(isolate, v8::Object::New(isolate));
g1.SetWeak();
g2.Reset(isolate, v8::Object::New(isolate));
g2.SetWeak();
}
CHECK_EQ(0, isolate->NumberOfPhantomHandleResetsSinceLastCall());
CcTest::i_isolate()->heap()->CollectAllAvailableGarbage();
CHECK_EQ(2, isolate->NumberOfPhantomHandleResetsSinceLastCall());
CHECK_EQ(0, isolate->NumberOfPhantomHandleResetsSinceLastCall());
}