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// 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/local-heap.h"
#include <memory>
#include "src/base/platform/mutex.h"
#include "src/common/globals.h"
#include "src/handles/local-handles.h"
#include "src/heap/heap-inl.h"
#include "src/heap/heap-write-barrier.h"
#include "src/heap/local-heap-inl.h"
#include "src/heap/marking-barrier.h"
#include "src/heap/safepoint.h"
namespace v8 {
namespace internal {
namespace {
thread_local LocalHeap* current_local_heap = nullptr;
} // namespace
LocalHeap* LocalHeap::Current() { return current_local_heap; }
LocalHeap::LocalHeap(Heap* heap,
std::unique_ptr<PersistentHandles> persistent_handles)
: heap_(heap),
state_(ThreadState::Running),
safepoint_requested_(false),
allocation_failed_(false),
prev_(nullptr),
next_(nullptr),
handles_(new LocalHandles),
persistent_handles_(std::move(persistent_handles)),
marking_barrier_(new MarkingBarrier(this)),
old_space_allocator_(this, heap->old_space()) {
heap_->safepoint()->AddLocalHeap(this);
if (persistent_handles_) {
persistent_handles_->Attach(this);
}
DCHECK_NULL(current_local_heap);
current_local_heap = this;
// TODO(ulan): Ensure that LocalHeap cannot be created without --local-heaps.
if (FLAG_local_heaps) {
WriteBarrier::SetForThread(marking_barrier_.get());
if (heap_->incremental_marking()->IsMarking()) {
marking_barrier_->Activate(heap_->incremental_marking()->IsCompacting());
}
}
}
LocalHeap::~LocalHeap() {
// TODO(ulan): Ensure that LocalHeap cannot be created without --local-heaps.
if (FLAG_local_heaps) {
marking_barrier_->Publish();
WriteBarrier::ClearForThread(marking_barrier_.get());
}
// Give up LAB before parking thread
old_space_allocator_.FreeLinearAllocationArea();
// Park thread since removing the local heap could block.
EnsureParkedBeforeDestruction();
heap_->safepoint()->RemoveLocalHeap(this);
DCHECK_EQ(current_local_heap, this);
current_local_heap = nullptr;
}
void LocalHeap::EnsurePersistentHandles() {
if (!persistent_handles_) {
persistent_handles_.reset(
heap_->isolate()->NewPersistentHandles().release());
persistent_handles_->Attach(this);
}
}
std::unique_ptr<PersistentHandles> LocalHeap::DetachPersistentHandles() {
if (persistent_handles_) persistent_handles_->Detach();
return std::move(persistent_handles_);
}
#ifdef DEBUG
bool LocalHeap::ContainsPersistentHandle(Address* location) {
return persistent_handles_ ? persistent_handles_->Contains(location) : false;
}
bool LocalHeap::ContainsLocalHandle(Address* location) {
return handles_ ? handles_->Contains(location) : false;
}
bool LocalHeap::IsHandleDereferenceAllowed() {
DCHECK_EQ(LocalHeap::Current(), this);
return state_ == ThreadState::Running;
}
#endif
bool LocalHeap::IsParked() {
DCHECK_EQ(LocalHeap::Current(), this);
return state_ == ThreadState::Parked;
}
void LocalHeap::Park() {
base::MutexGuard guard(&state_mutex_);
CHECK(state_ == ThreadState::Running);
state_ = ThreadState::Parked;
state_change_.NotifyAll();
}
void LocalHeap::Unpark() {
base::MutexGuard guard(&state_mutex_);
CHECK(state_ == ThreadState::Parked);
state_ = ThreadState::Running;
}
void LocalHeap::EnsureParkedBeforeDestruction() {
base::MutexGuard guard(&state_mutex_);
state_ = ThreadState::Parked;
state_change_.NotifyAll();
}
void LocalHeap::RequestSafepoint() {
safepoint_requested_.store(true, std::memory_order_relaxed);
}
void LocalHeap::ClearSafepointRequested() {
safepoint_requested_.store(false, std::memory_order_relaxed);
}
void LocalHeap::EnterSafepoint() {
DCHECK_EQ(LocalHeap::Current(), this);
if (state_ == ThreadState::Running) heap_->safepoint()->EnterFromThread(this);
}
void LocalHeap::FreeLinearAllocationArea() {
old_space_allocator_.FreeLinearAllocationArea();
}
void LocalHeap::MakeLinearAllocationAreaIterable() {
old_space_allocator_.MakeLinearAllocationAreaIterable();
}
void LocalHeap::MarkLinearAllocationAreaBlack() {
old_space_allocator_.MarkLinearAllocationAreaBlack();
}
void LocalHeap::UnmarkLinearAllocationArea() {
old_space_allocator_.UnmarkLinearAllocationArea();
}
Address LocalHeap::PerformCollectionAndAllocateAgain(
int object_size, AllocationType type, AllocationOrigin origin,
AllocationAlignment alignment) {
allocation_failed_ = true;
static const int kMaxNumberOfRetries = 3;
for (int i = 0; i < kMaxNumberOfRetries; i++) {
{
ParkedScope scope(this);
heap_->RequestAndWaitForCollection();
}
AllocationResult result = AllocateRaw(object_size, type, origin, alignment);
if (!result.IsRetry()) {
allocation_failed_ = false;
return result.ToObjectChecked().address();
}
}
heap_->FatalProcessOutOfMemory("LocalHeap: allocation failed");
}
} // namespace internal
} // namespace v8
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