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// Copyright 2015 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/execution/isolate.h"
#include "src/heap/factory.h"
#include "src/heap/heap-inl.h"
#include "src/heap/mark-compact.h"
#include "src/heap/memory-chunk.h"
#include "src/heap/remembered-set-inl.h"
#include "src/objects/objects-inl.h"
#include "test/cctest/cctest.h"
#include "test/cctest/heap/heap-tester.h"
#include "test/cctest/heap/heap-utils.h"
namespace v8 {
namespace internal {
namespace heap {
namespace {
void CheckInvariantsOfAbortedPage(Page* page) {
// Check invariants:
// 1) Markbits are cleared
// 2) The page is not marked as evacuation candidate anymore
// 3) The page is not marked as aborted compaction anymore.
CHECK(page->heap()
->mark_compact_collector()
->non_atomic_marking_state()
->bitmap(page)
->IsClean());
CHECK(!page->IsEvacuationCandidate());
CHECK(!page->IsFlagSet(Page::COMPACTION_WAS_ABORTED));
}
void CheckAllObjectsOnPage(const std::vector<Handle<FixedArray>>& handles,
Page* page) {
for (Handle<FixedArray> fixed_array : handles) {
CHECK(Page::FromHeapObject(*fixed_array) == page);
}
}
} // namespace
HEAP_TEST(CompactionFullAbortedPage) {
if (FLAG_never_compact) return;
// Test the scenario where we reach OOM during compaction and the whole page
// is aborted.
// Disable concurrent sweeping to ensure memory is in an expected state, i.e.,
// we can reach the state of a half aborted page.
ManualGCScope manual_gc_scope;
FLAG_manual_evacuation_candidates_selection = true;
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
Heap* heap = isolate->heap();
{
HandleScope scope1(isolate);
heap::SealCurrentObjects(heap);
{
HandleScope scope2(isolate);
CHECK(heap->old_space()->Expand());
auto compaction_page_handles = heap::CreatePadding(
heap,
static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()),
AllocationType::kOld);
Page* to_be_aborted_page =
Page::FromHeapObject(*compaction_page_handles.front());
to_be_aborted_page->SetFlag(
MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
CheckAllObjectsOnPage(compaction_page_handles, to_be_aborted_page);
heap->set_force_oom(true);
CcTest::CollectAllGarbage();
heap->mark_compact_collector()->EnsureSweepingCompleted();
// Check that all handles still point to the same page, i.e., compaction
// has been aborted on the page.
for (Handle<FixedArray> object : compaction_page_handles) {
CHECK_EQ(to_be_aborted_page, Page::FromHeapObject(*object));
}
CheckInvariantsOfAbortedPage(to_be_aborted_page);
}
}
}
namespace {
int GetObjectSize(int objects_per_page) {
int allocatable =
static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage());
// Make sure that object_size is a multiple of kTaggedSize.
int object_size =
((allocatable / kTaggedSize) / objects_per_page) * kTaggedSize;
return Min(kMaxRegularHeapObjectSize, object_size);
}
} // namespace
HEAP_TEST(CompactionPartiallyAbortedPage) {
if (FLAG_never_compact) return;
// Test the scenario where we reach OOM during compaction and parts of the
// page have already been migrated to a new one.
// Disable concurrent sweeping to ensure memory is in an expected state, i.e.,
// we can reach the state of a half aborted page.
ManualGCScope manual_gc_scope;
FLAG_manual_evacuation_candidates_selection = true;
const int objects_per_page = 10;
const int object_size = GetObjectSize(objects_per_page);
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
Heap* heap = isolate->heap();
{
HandleScope scope1(isolate);
heap::SealCurrentObjects(heap);
{
HandleScope scope2(isolate);
// Fill another page with objects of size {object_size} (last one is
// properly adjusted).
CHECK(heap->old_space()->Expand());
auto compaction_page_handles = heap::CreatePadding(
heap,
static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()),
AllocationType::kOld, object_size);
Page* to_be_aborted_page =
Page::FromHeapObject(*compaction_page_handles.front());
to_be_aborted_page->SetFlag(
MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
CheckAllObjectsOnPage(compaction_page_handles, to_be_aborted_page);
{
// Add another page that is filled with {num_objects} objects of size
// {object_size}.
HandleScope scope3(isolate);
CHECK(heap->old_space()->Expand());
const int num_objects = 3;
std::vector<Handle<FixedArray>> page_to_fill_handles =
heap::CreatePadding(heap, object_size * num_objects,
AllocationType::kOld, object_size);
Page* page_to_fill =
Page::FromAddress(page_to_fill_handles.front()->address());
heap->set_force_oom(true);
CcTest::CollectAllGarbage();
heap->mark_compact_collector()->EnsureSweepingCompleted();
bool migration_aborted = false;
for (Handle<FixedArray> object : compaction_page_handles) {
// Once compaction has been aborted, all following objects still have
// to be on the initial page.
CHECK(!migration_aborted ||
(Page::FromHeapObject(*object) == to_be_aborted_page));
if (Page::FromHeapObject(*object) == to_be_aborted_page) {
// This object has not been migrated.
migration_aborted = true;
} else {
CHECK_EQ(Page::FromHeapObject(*object), page_to_fill);
}
}
// Check that we actually created a scenario with a partially aborted
// page.
CHECK(migration_aborted);
CheckInvariantsOfAbortedPage(to_be_aborted_page);
}
}
}
}
HEAP_TEST(CompactionPartiallyAbortedPageWithInvalidatedSlots) {
if (FLAG_never_compact) return;
// Test evacuating a page partially when it contains recorded
// slots and invalidated objects.
// Disable concurrent sweeping to ensure memory is in an expected state, i.e.,
// we can reach the state of a half aborted page.
ManualGCScope manual_gc_scope;
FLAG_manual_evacuation_candidates_selection = true;
const int objects_per_page = 10;
const int object_size = GetObjectSize(objects_per_page);
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
Heap* heap = isolate->heap();
{
HandleScope scope1(isolate);
heap::SealCurrentObjects(heap);
{
HandleScope scope2(isolate);
// Fill another page with objects of size {object_size} (last one is
// properly adjusted).
CHECK(heap->old_space()->Expand());
auto compaction_page_handles = heap::CreatePadding(
heap,
static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()),
AllocationType::kOld, object_size);
Page* to_be_aborted_page =
Page::FromHeapObject(*compaction_page_handles.front());
for (Handle<FixedArray> object : compaction_page_handles) {
CHECK_EQ(Page::FromHeapObject(*object), to_be_aborted_page);
for (int i = 0; i < object->length(); i++) {
RememberedSet<OLD_TO_NEW>::Insert<AccessMode::ATOMIC>(
to_be_aborted_page, object->RawFieldOfElementAt(i).address());
}
}
// First object is going to be evacuated.
to_be_aborted_page->RegisterObjectWithInvalidatedSlots<OLD_TO_NEW>(
*compaction_page_handles.front());
// Last object is NOT going to be evacuated.
// This happens since not all objects fit on the only other page in the
// old space, the GC isn't allowed to allocate another page.
to_be_aborted_page->RegisterObjectWithInvalidatedSlots<OLD_TO_NEW>(
*compaction_page_handles.back());
to_be_aborted_page->SetFlag(
MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
{
// Add another page that is filled with {num_objects} objects of size
// {object_size}.
HandleScope scope3(isolate);
CHECK(heap->old_space()->Expand());
const int num_objects = 3;
std::vector<Handle<FixedArray>> page_to_fill_handles =
heap::CreatePadding(heap, object_size * num_objects,
AllocationType::kOld, object_size);
Page* page_to_fill =
Page::FromAddress(page_to_fill_handles.front()->address());
heap->set_force_oom(true);
CcTest::CollectAllGarbage();
heap->mark_compact_collector()->EnsureSweepingCompleted();
CHECK_EQ(Page::FromHeapObject(*compaction_page_handles.front()),
page_to_fill);
CHECK_EQ(Page::FromHeapObject(*compaction_page_handles.back()),
to_be_aborted_page);
}
}
}
}
HEAP_TEST(CompactionPartiallyAbortedPageIntraAbortedPointers) {
if (FLAG_never_compact) return;
// Test the scenario where we reach OOM during compaction and parts of the
// page have already been migrated to a new one. Objects on the aborted page
// are linked together. This test makes sure that intra-aborted page pointers
// get properly updated.
// Disable concurrent sweeping to ensure memory is in an expected state, i.e.,
// we can reach the state of a half aborted page.
ManualGCScope manual_gc_scope;
FLAG_manual_evacuation_candidates_selection = true;
const int objects_per_page = 10;
const int object_size = GetObjectSize(objects_per_page);
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
Heap* heap = isolate->heap();
{
HandleScope scope1(isolate);
Handle<FixedArray> root_array =
isolate->factory()->NewFixedArray(10, AllocationType::kOld);
heap::SealCurrentObjects(heap);
Page* to_be_aborted_page = nullptr;
{
HandleScope temporary_scope(isolate);
// Fill a fresh page with objects of size {object_size} (last one is
// properly adjusted).
CHECK(heap->old_space()->Expand());
std::vector<Handle<FixedArray>> compaction_page_handles =
heap::CreatePadding(
heap,
static_cast<int>(
MemoryChunkLayout::AllocatableMemoryInDataPage()),
AllocationType::kOld, object_size);
to_be_aborted_page =
Page::FromHeapObject(*compaction_page_handles.front());
to_be_aborted_page->SetFlag(
MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
for (size_t i = compaction_page_handles.size() - 1; i > 0; i--) {
compaction_page_handles[i]->set(0, *compaction_page_handles[i - 1]);
}
root_array->set(0, *compaction_page_handles.back());
CheckAllObjectsOnPage(compaction_page_handles, to_be_aborted_page);
}
{
// Add another page that is filled with {num_objects} objects of size
// {object_size}.
HandleScope scope3(isolate);
CHECK(heap->old_space()->Expand());
const int num_objects = 2;
int used_memory = object_size * num_objects;
std::vector<Handle<FixedArray>> page_to_fill_handles =
heap::CreatePadding(heap, used_memory, AllocationType::kOld,
object_size);
Page* page_to_fill = Page::FromHeapObject(*page_to_fill_handles.front());
heap->set_force_oom(true);
CcTest::CollectAllGarbage();
heap->mark_compact_collector()->EnsureSweepingCompleted();
// The following check makes sure that we compacted "some" objects, while
// leaving others in place.
bool in_place = true;
Handle<FixedArray> current = root_array;
while (current->get(0) != ReadOnlyRoots(heap).undefined_value()) {
current =
Handle<FixedArray>(FixedArray::cast(current->get(0)), isolate);
CHECK(current->IsFixedArray());
if (Page::FromHeapObject(*current) != to_be_aborted_page) {
in_place = false;
}
bool on_aborted_page =
Page::FromHeapObject(*current) == to_be_aborted_page;
bool on_fill_page = Page::FromHeapObject(*current) == page_to_fill;
CHECK((in_place && on_aborted_page) || (!in_place && on_fill_page));
}
// Check that we at least migrated one object, as otherwise the test would
// not trigger.
CHECK(!in_place);
CheckInvariantsOfAbortedPage(to_be_aborted_page);
}
}
}
HEAP_TEST(CompactionPartiallyAbortedPageWithRememberedSetEntries) {
if (FLAG_never_compact || FLAG_always_promote_young_mc) return;
// Test the scenario where we reach OOM during compaction and parts of the
// page have already been migrated to a new one. Objects on the aborted page
// are linked together and the very first object on the aborted page points
// into new space. The test verifies that the remembered set entries are
// properly cleared and rebuilt after aborting a page. Failing to do so can
// result in other objects being allocated in the free space where their
// payload looks like a valid new space pointer.
// Disable concurrent sweeping to ensure memory is in an expected state, i.e.,
// we can reach the state of a half aborted page.
ManualGCScope manual_gc_scope;
FLAG_manual_evacuation_candidates_selection = true;
const int objects_per_page = 10;
const int object_size = GetObjectSize(objects_per_page);
CcTest::InitializeVM();
Isolate* isolate = CcTest::i_isolate();
Heap* heap = isolate->heap();
{
HandleScope scope1(isolate);
Handle<FixedArray> root_array =
isolate->factory()->NewFixedArray(10, AllocationType::kOld);
heap::SealCurrentObjects(heap);
Page* to_be_aborted_page = nullptr;
{
HandleScope temporary_scope(isolate);
// Fill another page with objects of size {object_size} (last one is
// properly adjusted).
CHECK(heap->old_space()->Expand());
auto compaction_page_handles = heap::CreatePadding(
heap,
static_cast<int>(MemoryChunkLayout::AllocatableMemoryInDataPage()),
AllocationType::kOld, object_size);
// Sanity check that we have enough space for linking up arrays.
CHECK_GE(compaction_page_handles.front()->length(), 2);
to_be_aborted_page =
Page::FromHeapObject(*compaction_page_handles.front());
to_be_aborted_page->SetFlag(
MemoryChunk::FORCE_EVACUATION_CANDIDATE_FOR_TESTING);
for (size_t i = compaction_page_handles.size() - 1; i > 0; i--) {
compaction_page_handles[i]->set(0, *compaction_page_handles[i - 1]);
}
root_array->set(0, *compaction_page_handles.back());
Handle<FixedArray> new_space_array =
isolate->factory()->NewFixedArray(1, AllocationType::kYoung);
CHECK(Heap::InYoungGeneration(*new_space_array));
compaction_page_handles.front()->set(1, *new_space_array);
CheckAllObjectsOnPage(compaction_page_handles, to_be_aborted_page);
}
{
// Add another page that is filled with {num_objects} objects of size
// {object_size}.
HandleScope scope3(isolate);
CHECK(heap->old_space()->Expand());
const int num_objects = 2;
int used_memory = object_size * num_objects;
std::vector<Handle<FixedArray>> page_to_fill_handles =
heap::CreatePadding(heap, used_memory, AllocationType::kOld,
object_size);
Page* page_to_fill = Page::FromHeapObject(*page_to_fill_handles.front());
heap->set_force_oom(true);
CcTest::CollectAllGarbage();
heap->mark_compact_collector()->EnsureSweepingCompleted();
// The following check makes sure that we compacted "some" objects, while
// leaving others in place.
bool in_place = true;
Handle<FixedArray> current = root_array;
while (current->get(0) != ReadOnlyRoots(heap).undefined_value()) {
current =
Handle<FixedArray>(FixedArray::cast(current->get(0)), isolate);
CHECK(!Heap::InYoungGeneration(*current));
CHECK(current->IsFixedArray());
if (Page::FromHeapObject(*current) != to_be_aborted_page) {
in_place = false;
}
bool on_aborted_page =
Page::FromHeapObject(*current) == to_be_aborted_page;
bool on_fill_page = Page::FromHeapObject(*current) == page_to_fill;
CHECK((in_place && on_aborted_page) || (!in_place && on_fill_page));
}
// Check that we at least migrated one object, as otherwise the test would
// not trigger.
CHECK(!in_place);
CheckInvariantsOfAbortedPage(to_be_aborted_page);
// Allocate a new object in new space.
Handle<FixedArray> holder =
isolate->factory()->NewFixedArray(10, AllocationType::kYoung);
// Create a broken address that looks like a tagged pointer to a new space
// object.
Address broken_address = holder->address() + 2 * kTaggedSize + 1;
// Convert it to a vector to create a string from it.
Vector<const uint8_t> string_to_broken_addresss(
reinterpret_cast<const uint8_t*>(&broken_address), kTaggedSize);
Handle<String> string;
do {
// We know that the interesting slot will be on the aborted page and
// hence we allocate until we get our string on the aborted page.
// We used slot 1 in the fixed size array which corresponds to the
// the first word in the string. Since the first object definitely
// migrated we can just allocate until we hit the aborted page.
string = isolate->factory()
->NewStringFromOneByte(string_to_broken_addresss,
AllocationType::kOld)
.ToHandleChecked();
} while (Page::FromHeapObject(*string) != to_be_aborted_page);
// If remembered set entries are not properly filtered/reset for aborted
// pages we have now a broken address at an object slot in old space and
// the following scavenge will crash.
CcTest::CollectGarbage(NEW_SPACE);
}
}
}
} // namespace heap
} // namespace internal
} // namespace v8
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