v8/test/unittests/heap/cppgc/marker-unittest.cc
Omer Katz 18ff56600c cppgc: Eliminate marking boilerplate
Starting marking required Creating a Marker and calling StartMarking.
StartMarking should always have been called immediately after creating
the marker.
Since markers are not persisted between GC (a marker exists only while
marking is in progress), it makes sense to start marking implicitly when
a marker is created.

Calling StartMarking in MarkerBase ctor is inadvisable since subclasses
might still to initialize fields.
Using MarkerFactory instead guarantees that StartMarking is always
called immediately after creating a Marker.

Bug: chromium:1056170
Change-Id: Icbf11afd848e1618c204ca6bf951600b3ae9fef2
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2375199
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69601}
2020-08-28 09:41:06 +00:00

385 lines
14 KiB
C++

// Copyright 2020 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/cppgc/marker.h"
#include "include/cppgc/allocation.h"
#include "include/cppgc/internal/pointer-policies.h"
#include "include/cppgc/member.h"
#include "include/cppgc/persistent.h"
#include "src/heap/cppgc/heap-object-header.h"
#include "src/heap/cppgc/marking-visitor.h"
#include "src/heap/cppgc/stats-collector.h"
#include "test/unittests/heap/cppgc/tests.h"
#include "testing/gtest/include/gtest/gtest.h"
namespace cppgc {
namespace internal {
namespace {
class MarkerTest : public testing::TestWithHeap {
public:
using MarkingConfig = Marker::MarkingConfig;
void DoMarking(MarkingConfig::StackState stack_state) {
const MarkingConfig config = {MarkingConfig::CollectionType::kMajor,
stack_state};
auto* heap = Heap::From(GetHeap());
InitializeMarker(*heap, GetPlatformHandle().get(), config);
marker_->FinishMarking(stack_state);
marker_->ProcessWeakness();
// Pretend do finish sweeping as StatsCollector verifies that Notify*
// methods are called in the right order.
heap->stats_collector()->NotifySweepingCompleted();
}
void InitializeMarker(HeapBase& heap, cppgc::Platform* platform,
MarkingConfig config) {
marker_ =
MarkerFactory::CreateAndStartMarking<Marker>(heap, platform, config);
}
Marker* marker() const { return marker_.get(); }
private:
std::unique_ptr<Marker> marker_;
};
class GCed : public GarbageCollected<GCed> {
public:
void SetChild(GCed* child) { child_ = child; }
void SetWeakChild(GCed* child) { weak_child_ = child; }
GCed* child() const { return child_.Get(); }
GCed* weak_child() const { return weak_child_.Get(); }
void Trace(cppgc::Visitor* visitor) const {
visitor->Trace(child_);
visitor->Trace(weak_child_);
}
private:
Member<GCed> child_;
WeakMember<GCed> weak_child_;
};
template <typename T>
V8_NOINLINE T access(volatile const T& t) {
return t;
}
} // namespace
TEST_F(MarkerTest, PersistentIsMarked) {
Persistent<GCed> object = MakeGarbageCollected<GCed>(GetAllocationHandle());
HeapObjectHeader& header = HeapObjectHeader::FromPayload(object);
EXPECT_FALSE(header.IsMarked());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(header.IsMarked());
}
TEST_F(MarkerTest, ReachableMemberIsMarked) {
Persistent<GCed> parent = MakeGarbageCollected<GCed>(GetAllocationHandle());
parent->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
HeapObjectHeader& header = HeapObjectHeader::FromPayload(parent->child());
EXPECT_FALSE(header.IsMarked());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(header.IsMarked());
}
TEST_F(MarkerTest, UnreachableMemberIsNotMarked) {
Member<GCed> object = MakeGarbageCollected<GCed>(GetAllocationHandle());
HeapObjectHeader& header = HeapObjectHeader::FromPayload(object);
EXPECT_FALSE(header.IsMarked());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_FALSE(header.IsMarked());
}
TEST_F(MarkerTest, ObjectReachableFromStackIsMarked) {
GCed* object = MakeGarbageCollected<GCed>(GetAllocationHandle());
EXPECT_FALSE(HeapObjectHeader::FromPayload(object).IsMarked());
DoMarking(MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(HeapObjectHeader::FromPayload(object).IsMarked());
access(object);
}
TEST_F(MarkerTest, ObjectReachableOnlyFromStackIsNotMarkedIfStackIsEmpty) {
GCed* object = MakeGarbageCollected<GCed>(GetAllocationHandle());
HeapObjectHeader& header = HeapObjectHeader::FromPayload(object);
EXPECT_FALSE(header.IsMarked());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_FALSE(header.IsMarked());
access(object);
}
TEST_F(MarkerTest, WeakReferenceToUnreachableObjectIsCleared) {
{
WeakPersistent<GCed> weak_object =
MakeGarbageCollected<GCed>(GetAllocationHandle());
EXPECT_TRUE(weak_object);
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_FALSE(weak_object);
}
{
Persistent<GCed> parent = MakeGarbageCollected<GCed>(GetAllocationHandle());
parent->SetWeakChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
EXPECT_TRUE(parent->weak_child());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_FALSE(parent->weak_child());
}
}
TEST_F(MarkerTest, WeakReferenceToReachableObjectIsNotCleared) {
// Reachable from Persistent
{
Persistent<GCed> object = MakeGarbageCollected<GCed>(GetAllocationHandle());
WeakPersistent<GCed> weak_object(object);
EXPECT_TRUE(weak_object);
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(weak_object);
}
{
Persistent<GCed> object = MakeGarbageCollected<GCed>(GetAllocationHandle());
Persistent<GCed> parent = MakeGarbageCollected<GCed>(GetAllocationHandle());
parent->SetWeakChild(object);
EXPECT_TRUE(parent->weak_child());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(parent->weak_child());
}
// Reachable from Member
{
Persistent<GCed> parent = MakeGarbageCollected<GCed>(GetAllocationHandle());
WeakPersistent<GCed> weak_object(
MakeGarbageCollected<GCed>(GetAllocationHandle()));
parent->SetChild(weak_object);
EXPECT_TRUE(weak_object);
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(weak_object);
}
{
Persistent<GCed> parent = MakeGarbageCollected<GCed>(GetAllocationHandle());
parent->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
parent->SetWeakChild(parent->child());
EXPECT_TRUE(parent->weak_child());
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(parent->weak_child());
}
// Reachable from stack
{
GCed* object = MakeGarbageCollected<GCed>(GetAllocationHandle());
WeakPersistent<GCed> weak_object(object);
EXPECT_TRUE(weak_object);
DoMarking(MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(weak_object);
access(object);
}
{
GCed* object = MakeGarbageCollected<GCed>(GetAllocationHandle());
Persistent<GCed> parent = MakeGarbageCollected<GCed>(GetAllocationHandle());
parent->SetWeakChild(object);
EXPECT_TRUE(parent->weak_child());
DoMarking(MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(parent->weak_child());
access(object);
}
}
TEST_F(MarkerTest, DeepHierarchyIsMarked) {
static constexpr int kHierarchyDepth = 10;
Persistent<GCed> root = MakeGarbageCollected<GCed>(GetAllocationHandle());
GCed* parent = root;
for (int i = 0; i < kHierarchyDepth; ++i) {
parent->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
parent->SetWeakChild(parent->child());
parent = parent->child();
}
DoMarking(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(HeapObjectHeader::FromPayload(root).IsMarked());
parent = root;
for (int i = 0; i < kHierarchyDepth; ++i) {
EXPECT_TRUE(HeapObjectHeader::FromPayload(parent->child()).IsMarked());
EXPECT_TRUE(parent->weak_child());
parent = parent->child();
}
}
TEST_F(MarkerTest, NestedObjectsOnStackAreMarked) {
GCed* root = MakeGarbageCollected<GCed>(GetAllocationHandle());
root->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
root->child()->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
DoMarking(MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(HeapObjectHeader::FromPayload(root).IsMarked());
EXPECT_TRUE(HeapObjectHeader::FromPayload(root->child()).IsMarked());
EXPECT_TRUE(HeapObjectHeader::FromPayload(root->child()->child()).IsMarked());
}
namespace {
class GCedWithCallback : public GarbageCollected<GCedWithCallback> {
public:
template <typename Callback>
explicit GCedWithCallback(Callback callback) {
callback(this);
}
void Trace(Visitor*) const {}
};
} // namespace
TEST_F(MarkerTest, InConstructionObjectIsEventuallyMarkedEmptyStack) {
static const Marker::MarkingConfig config = {
MarkingConfig::CollectionType::kMajor,
MarkingConfig::StackState::kMayContainHeapPointers};
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(), config);
GCedWithCallback* object = MakeGarbageCollected<GCedWithCallback>(
GetAllocationHandle(), [marker = marker()](GCedWithCallback* obj) {
Member<GCedWithCallback> member(obj);
marker->VisitorForTesting().Trace(member);
});
EXPECT_TRUE(HeapObjectHeader::FromPayload(object).IsMarked());
marker()->FinishMarking(MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(HeapObjectHeader::FromPayload(object).IsMarked());
}
TEST_F(MarkerTest, InConstructionObjectIsEventuallyMarkedNonEmptyStack) {
static const Marker::MarkingConfig config = {
MarkingConfig::CollectionType::kMajor,
MarkingConfig::StackState::kMayContainHeapPointers};
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(), config);
MakeGarbageCollected<GCedWithCallback>(
GetAllocationHandle(), [marker = marker()](GCedWithCallback* obj) {
Member<GCedWithCallback> member(obj);
marker->VisitorForTesting().Trace(member);
EXPECT_TRUE(HeapObjectHeader::FromPayload(obj).IsMarked());
marker->FinishMarking(
MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(HeapObjectHeader::FromPayload(obj).IsMarked());
});
}
TEST_F(MarkerTest, SentinelNotClearedOnWeakPersistentHandling) {
static const Marker::MarkingConfig config = {
MarkingConfig::CollectionType::kMajor,
MarkingConfig::StackState::kNoHeapPointers};
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(), config);
Persistent<GCed> root = MakeGarbageCollected<GCed>(GetAllocationHandle());
auto* tmp = MakeGarbageCollected<GCed>(GetAllocationHandle());
root->SetWeakChild(tmp);
marker()->FinishMarking(MarkingConfig::StackState::kNoHeapPointers);
root->SetWeakChild(kSentinelPointer);
marker()->ProcessWeakness();
EXPECT_EQ(kSentinelPointer, root->weak_child());
}
// Incremental Marking
class IncrementalMarkingTest : public testing::TestWithHeap {
public:
using MarkingConfig = Marker::MarkingConfig;
static constexpr MarkingConfig IncrementalPreciseMarkingConfig = {
MarkingConfig::CollectionType::kMajor,
MarkingConfig::StackState::kNoHeapPointers,
MarkingConfig::MarkingType::kIncremental};
static constexpr MarkingConfig IncrementalConservativeMarkingConfig = {
MarkingConfig::CollectionType::kMajor,
MarkingConfig::StackState::kMayContainHeapPointers,
MarkingConfig::MarkingType::kIncremental};
void FinishSteps(MarkingConfig::StackState stack_state) {
SingleStep(stack_state, std::numeric_limits<size_t>::max());
}
void FinishMarking() {
marker_->FinishMarking(MarkingConfig::StackState::kMayContainHeapPointers);
marker_->ProcessWeakness();
// Pretend do finish sweeping as StatsCollector verifies that Notify*
// methods are called in the right order.
Heap::From(GetHeap())->stats_collector()->NotifySweepingCompleted();
}
void InitializeMarker(HeapBase& heap, cppgc::Platform* platform,
MarkingConfig config) {
marker_ =
MarkerFactory::CreateAndStartMarking<Marker>(heap, platform, config);
}
Marker* marker() const { return marker_.get(); }
private:
bool SingleStep(MarkingConfig::StackState stack_state, size_t bytes_to_mark) {
return marker_->IncrementalMarkingStepForTesting(stack_state,
bytes_to_mark);
}
std::unique_ptr<Marker> marker_;
};
constexpr IncrementalMarkingTest::MarkingConfig
IncrementalMarkingTest::IncrementalPreciseMarkingConfig;
constexpr IncrementalMarkingTest::MarkingConfig
IncrementalMarkingTest::IncrementalConservativeMarkingConfig;
TEST_F(IncrementalMarkingTest, RootIsMarkedAfterMarkingStarted) {
Persistent<GCed> root = MakeGarbageCollected<GCed>(GetAllocationHandle());
EXPECT_FALSE(HeapObjectHeader::FromPayload(root).IsMarked());
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(),
IncrementalPreciseMarkingConfig);
EXPECT_TRUE(HeapObjectHeader::FromPayload(root).IsMarked());
FinishMarking();
}
TEST_F(IncrementalMarkingTest, MemberIsMarkedAfterMarkingSteps) {
Persistent<GCed> root = MakeGarbageCollected<GCed>(GetAllocationHandle());
root->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
HeapObjectHeader& header = HeapObjectHeader::FromPayload(root->child());
EXPECT_FALSE(header.IsMarked());
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(),
IncrementalPreciseMarkingConfig);
FinishSteps(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(header.IsMarked());
FinishMarking();
}
TEST_F(IncrementalMarkingTest,
MemberWithWriteBarrierIsMarkedAfterMarkingSteps) {
Persistent<GCed> root = MakeGarbageCollected<GCed>(GetAllocationHandle());
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(),
IncrementalPreciseMarkingConfig);
root->SetChild(MakeGarbageCollected<GCed>(GetAllocationHandle()));
HeapObjectHeader& header = HeapObjectHeader::FromPayload(root->child());
EXPECT_FALSE(header.IsMarked());
FinishSteps(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(header.IsMarked());
FinishMarking();
}
namespace {
class Holder : public GarbageCollected<Holder> {
public:
void Trace(Visitor* visitor) const { visitor->Trace(member_); }
Member<GCedWithCallback> member_;
};
} // namespace
TEST_F(IncrementalMarkingTest, IncrementalStepDuringAllocation) {
Persistent<Holder> holder =
MakeGarbageCollected<Holder>(GetAllocationHandle());
InitializeMarker(*Heap::From(GetHeap()), GetPlatformHandle().get(),
IncrementalPreciseMarkingConfig);
const HeapObjectHeader* header;
MakeGarbageCollected<GCedWithCallback>(
GetAllocationHandle(), [this, &holder, &header](GCedWithCallback* obj) {
header = &HeapObjectHeader::FromPayload(obj);
holder->member_ = obj;
EXPECT_FALSE(header->IsMarked());
FinishSteps(MarkingConfig::StackState::kMayContainHeapPointers);
EXPECT_TRUE(header->IsMarked());
});
FinishSteps(MarkingConfig::StackState::kNoHeapPointers);
EXPECT_TRUE(header->IsMarked());
FinishMarking();
}
} // namespace internal
} // namespace cppgc