blob: e18cf04248a4ede9bf3bf8f347be3e38fc188a20 [file] [log] [blame]
/*
* Copyright (C) 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "transaction.h"
#include "base/stl_util.h"
#include "base/logging.h"
#include "gc/accounting/card_table-inl.h"
#include "intern_table.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include <list>
namespace art {
// TODO: remove (only used for debugging purpose).
static constexpr bool kEnableTransactionStats = false;
Transaction::Transaction() : log_lock_("transaction log lock", kTransactionLogLock) {
CHECK(Runtime::Current()->IsCompiler());
}
Transaction::~Transaction() {
if (kEnableTransactionStats) {
MutexLock mu(Thread::Current(), log_lock_);
size_t objects_count = object_logs_.size();
size_t field_values_count = 0;
for (auto it : object_logs_) {
field_values_count += it.second.Size();
}
size_t array_count = array_logs_.size();
size_t array_values_count = 0;
for (auto it : array_logs_) {
array_values_count += it.second.Size();
}
size_t string_count = intern_string_logs_.size();
LOG(INFO) << "Transaction::~Transaction"
<< ": objects_count=" << objects_count
<< ", field_values_count=" << field_values_count
<< ", array_count=" << array_count
<< ", array_values_count=" << array_values_count
<< ", string_count=" << string_count;
}
}
void Transaction::RecordWriteField32(mirror::Object* obj, MemberOffset field_offset, uint32_t value,
bool is_volatile) {
DCHECK(obj != nullptr);
MutexLock mu(Thread::Current(), log_lock_);
ObjectLog& object_log = object_logs_[obj];
object_log.Log32BitsValue(field_offset, value, is_volatile);
}
void Transaction::RecordWriteField64(mirror::Object* obj, MemberOffset field_offset, uint64_t value,
bool is_volatile) {
DCHECK(obj != nullptr);
MutexLock mu(Thread::Current(), log_lock_);
ObjectLog& object_log = object_logs_[obj];
object_log.Log64BitsValue(field_offset, value, is_volatile);
}
void Transaction::RecordWriteFieldReference(mirror::Object* obj, MemberOffset field_offset,
mirror::Object* value, bool is_volatile) {
DCHECK(obj != nullptr);
MutexLock mu(Thread::Current(), log_lock_);
ObjectLog& object_log = object_logs_[obj];
object_log.LogReferenceValue(field_offset, value, is_volatile);
}
void Transaction::RecordWriteArray(mirror::Array* array, size_t index, uint64_t value) {
DCHECK(array != nullptr);
DCHECK(array->IsArrayInstance());
DCHECK(!array->IsObjectArray());
MutexLock mu(Thread::Current(), log_lock_);
ArrayLog& array_log = array_logs_[array];
array_log.LogValue(index, value);
}
void Transaction::RecordStrongStringInsertion(mirror::String* s, uint32_t hash_code) {
InternStringLog log(s, hash_code, InternStringLog::kStrongString, InternStringLog::kInsert);
LogInternedString(log);
}
void Transaction::RecordWeakStringInsertion(mirror::String* s, uint32_t hash_code) {
InternStringLog log(s, hash_code, InternStringLog::kWeakString, InternStringLog::kInsert);
LogInternedString(log);
}
void Transaction::RecordStrongStringRemoval(mirror::String* s, uint32_t hash_code) {
InternStringLog log(s, hash_code, InternStringLog::kStrongString, InternStringLog::kRemove);
LogInternedString(log);
}
void Transaction::RecordWeakStringRemoval(mirror::String* s, uint32_t hash_code) {
InternStringLog log(s, hash_code, InternStringLog::kWeakString, InternStringLog::kRemove);
LogInternedString(log);
}
void Transaction::LogInternedString(InternStringLog& log) {
Locks::intern_table_lock_->AssertExclusiveHeld(Thread::Current());
MutexLock mu(Thread::Current(), log_lock_);
intern_string_logs_.push_front(log);
}
void Transaction::Abort() {
CHECK(!Runtime::Current()->IsActiveTransaction());
Thread* self = Thread::Current();
self->AssertNoPendingException();
MutexLock mu1(self, *Locks::intern_table_lock_);
MutexLock mu2(self, log_lock_);
UndoObjectModifications();
UndoArrayModifications();
UndoInternStringTableModifications();
}
void Transaction::UndoObjectModifications() {
// TODO we may not need to restore objects allocated during this transaction. Or we could directly
// remove them from the heap.
for (auto it : object_logs_) {
it.second.Undo(it.first);
}
object_logs_.clear();
}
void Transaction::UndoArrayModifications() {
// TODO we may not need to restore array allocated during this transaction. Or we could directly
// remove them from the heap.
for (auto it : array_logs_) {
it.second.Undo(it.first);
}
array_logs_.clear();
}
void Transaction::UndoInternStringTableModifications() {
InternTable* const intern_table = Runtime::Current()->GetInternTable();
// We want to undo each operation from the most recent to the oldest. List has been filled so the
// most recent operation is at list begin so just have to iterate over it.
for (InternStringLog& string_log : intern_string_logs_) {
string_log.Undo(intern_table);
}
intern_string_logs_.clear();
}
void Transaction::VisitRoots(RootCallback* callback, void* arg) {
MutexLock mu(Thread::Current(), log_lock_);
VisitObjectLogs(callback, arg);
VisitArrayLogs(callback, arg);
VisitStringLogs(callback, arg);
}
void Transaction::VisitObjectLogs(RootCallback* callback, void* arg) {
// List of moving roots.
typedef std::pair<mirror::Object*, mirror::Object*> ObjectPair;
std::list<ObjectPair> moving_roots;
// Visit roots.
for (auto it : object_logs_) {
it.second.VisitRoots(callback, arg);
mirror::Object* old_root = it.first;
mirror::Object* new_root = old_root;
callback(&new_root, arg, 0, kRootUnknown);
if (new_root != old_root) {
moving_roots.push_back(std::make_pair(old_root, new_root));
}
}
// Update object logs with moving roots.
for (const ObjectPair& pair : moving_roots) {
mirror::Object* old_root = pair.first;
mirror::Object* new_root = pair.second;
auto old_root_it = object_logs_.find(old_root);
CHECK(old_root_it != object_logs_.end());
CHECK(object_logs_.find(new_root) == object_logs_.end());
object_logs_.insert(std::make_pair(new_root, old_root_it->second));
object_logs_.erase(old_root_it);
}
}
void Transaction::VisitArrayLogs(RootCallback* callback, void* arg) {
// List of moving roots.
typedef std::pair<mirror::Array*, mirror::Array*> ArrayPair;
std::list<ArrayPair> moving_roots;
for (auto it : array_logs_) {
mirror::Array* old_root = it.first;
CHECK(!old_root->IsObjectArray());
mirror::Array* new_root = old_root;
callback(reinterpret_cast<mirror::Object**>(&new_root), arg, 0, kRootUnknown);
if (new_root != old_root) {
moving_roots.push_back(std::make_pair(old_root, new_root));
}
}
// Update array logs with moving roots.
for (const ArrayPair& pair : moving_roots) {
mirror::Array* old_root = pair.first;
mirror::Array* new_root = pair.second;
auto old_root_it = array_logs_.find(old_root);
CHECK(old_root_it != array_logs_.end());
CHECK(array_logs_.find(new_root) == array_logs_.end());
array_logs_.insert(std::make_pair(new_root, old_root_it->second));
array_logs_.erase(old_root_it);
}
}
void Transaction::VisitStringLogs(RootCallback* callback, void* arg) {
for (InternStringLog& log : intern_string_logs_) {
log.VisitRoots(callback, arg);
}
}
void Transaction::ObjectLog::Log32BitsValue(MemberOffset offset, uint32_t value, bool is_volatile) {
auto it = field_values_.find(offset.Uint32Value());
if (it == field_values_.end()) {
ObjectLog::FieldValue field_value;
field_value.value = value;
field_value.is_volatile = is_volatile;
field_value.kind = ObjectLog::k32Bits;
field_values_.insert(std::make_pair(offset.Uint32Value(), field_value));
}
}
void Transaction::ObjectLog::Log64BitsValue(MemberOffset offset, uint64_t value, bool is_volatile) {
auto it = field_values_.find(offset.Uint32Value());
if (it == field_values_.end()) {
ObjectLog::FieldValue field_value;
field_value.value = value;
field_value.is_volatile = is_volatile;
field_value.kind = ObjectLog::k64Bits;
field_values_.insert(std::make_pair(offset.Uint32Value(), field_value));
}
}
void Transaction::ObjectLog::LogReferenceValue(MemberOffset offset, mirror::Object* obj, bool is_volatile) {
auto it = field_values_.find(offset.Uint32Value());
if (it == field_values_.end()) {
ObjectLog::FieldValue field_value;
field_value.value = reinterpret_cast<uintptr_t>(obj);
field_value.is_volatile = is_volatile;
field_value.kind = ObjectLog::kReference;
field_values_.insert(std::make_pair(offset.Uint32Value(), field_value));
}
}
void Transaction::ObjectLog::Undo(mirror::Object* obj) {
for (auto& it : field_values_) {
// Garbage collector needs to access object's class and array's length. So we don't rollback
// these values.
MemberOffset field_offset(it.first);
if (field_offset.Uint32Value() == mirror::Class::ClassOffset().Uint32Value()) {
// Skip Object::class field.
continue;
}
if (obj->IsArrayInstance() &&
field_offset.Uint32Value() == mirror::Array::LengthOffset().Uint32Value()) {
// Skip Array::length field.
continue;
}
FieldValue& field_value = it.second;
UndoFieldWrite(obj, field_offset, field_value);
}
}
void Transaction::ObjectLog::UndoFieldWrite(mirror::Object* obj, MemberOffset field_offset,
const FieldValue& field_value) {
// TODO We may want to abort a transaction while still being in transaction mode. In this case,
// we'd need to disable the check.
constexpr bool kCheckTransaction = true;
switch (field_value.kind) {
case k32Bits:
obj->SetField32<false, kCheckTransaction>(field_offset, static_cast<uint32_t>(field_value.value),
field_value.is_volatile);
break;
case k64Bits:
obj->SetField64<false, kCheckTransaction>(field_offset, field_value.value,
field_value.is_volatile);
break;
case kReference:
obj->SetFieldObject<false, kCheckTransaction>(field_offset,
reinterpret_cast<mirror::Object*>(field_value.value),
field_value.is_volatile);
break;
default:
LOG(FATAL) << "Unknown value kind " << field_value.kind;
break;
}
}
void Transaction::ObjectLog::VisitRoots(RootCallback* callback, void* arg) {
for (auto it : field_values_) {
FieldValue& field_value = it.second;
if (field_value.kind == ObjectLog::kReference) {
mirror::Object* obj =
reinterpret_cast<mirror::Object*>(static_cast<uintptr_t>(field_value.value));
if (obj != nullptr) {
callback(&obj, arg, 0, kRootUnknown);
field_value.value = reinterpret_cast<uintptr_t>(obj);
}
}
}
}
void Transaction::InternStringLog::Undo(InternTable* intern_table) {
DCHECK(intern_table != nullptr);
switch (string_op_) {
case InternStringLog::kInsert: {
switch (string_kind_) {
case InternStringLog::kStrongString:
intern_table->RemoveStrongFromTransaction(str_, hash_code_);
break;
case InternStringLog::kWeakString:
intern_table->RemoveWeakFromTransaction(str_, hash_code_);
break;
default:
LOG(FATAL) << "Unknown interned string kind";
break;
}
break;
}
case InternStringLog::kRemove: {
switch (string_kind_) {
case InternStringLog::kStrongString:
intern_table->InsertStrongFromTransaction(str_, hash_code_);
break;
case InternStringLog::kWeakString:
intern_table->InsertWeakFromTransaction(str_, hash_code_);
break;
default:
LOG(FATAL) << "Unknown interned string kind";
break;
}
break;
}
default:
LOG(FATAL) << "Unknown interned string op";
break;
}
}
void Transaction::InternStringLog::VisitRoots(RootCallback* callback, void* arg) {
callback(reinterpret_cast<mirror::Object**>(&str_), arg, 0, kRootInternedString);
}
void Transaction::ArrayLog::LogValue(size_t index, uint64_t value) {
auto it = array_values_.find(index);
if (it == array_values_.end()) {
array_values_.insert(std::make_pair(index, value));
}
}
void Transaction::ArrayLog::Undo(mirror::Array* array) {
DCHECK(array != nullptr);
DCHECK(array->IsArrayInstance());
Primitive::Type type = array->GetClass()->GetComponentType()->GetPrimitiveType();
for (auto it : array_values_) {
UndoArrayWrite(array, type, it.first, it.second);
}
}
void Transaction::ArrayLog::UndoArrayWrite(mirror::Array* array, Primitive::Type array_type,
size_t index, uint64_t value) {
// TODO We may want to abort a transaction while still being in transaction mode. In this case,
// we'd need to disable the check.
switch (array_type) {
case Primitive::kPrimBoolean:
array->AsBooleanArray()->SetWithoutChecks<false>(index, static_cast<uint8_t>(value));
break;
case Primitive::kPrimByte:
array->AsByteArray()->SetWithoutChecks<false>(index, static_cast<int8_t>(value));
break;
case Primitive::kPrimChar:
array->AsCharArray()->SetWithoutChecks<false>(index, static_cast<uint16_t>(value));
break;
case Primitive::kPrimShort:
array->AsShortArray()->SetWithoutChecks<false>(index, static_cast<int16_t>(value));
break;
case Primitive::kPrimInt:
array->AsIntArray()->SetWithoutChecks<false>(index, static_cast<int32_t>(value));
break;
case Primitive::kPrimFloat:
array->AsFloatArray()->SetWithoutChecks<false>(index, static_cast<float>(value));
break;
case Primitive::kPrimLong:
array->AsLongArray()->SetWithoutChecks<false>(index, static_cast<int64_t>(value));
break;
case Primitive::kPrimDouble:
array->AsDoubleArray()->SetWithoutChecks<false>(index, static_cast<double>(value));
break;
case Primitive::kPrimNot:
LOG(FATAL) << "ObjectArray should be treated as Object";
break;
default:
LOG(FATAL) << "Unsupported type " << array_type;
}
}
} // namespace art