blob: ccaa6b1befb85b47720edd00ba28d9977e9aedbe [file] [log] [blame]
// Copyright 2012 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 <atomic>
#include "src/execution/isolate.h"
namespace v8 {
namespace internal {
class RootVisitor;
class ThreadLocalTop;
class ThreadState {
// Returns nullptr after the last one.
ThreadState* Next();
enum List { FREE_LIST, IN_USE_LIST };
void LinkInto(List list);
void Unlink();
// Id of thread.
void set_id(ThreadId id) { id_ = id; }
ThreadId id() { return id_; }
// Get data area for archiving a thread.
char* data() { return data_; }
explicit ThreadState(ThreadManager* thread_manager);
void AllocateSpace();
ThreadId id_;
char* data_;
ThreadState* next_;
ThreadState* previous_;
ThreadManager* thread_manager_;
friend class ThreadManager;
class ThreadVisitor {
// ThreadLocalTop may be only available during this call.
virtual void VisitThread(Isolate* isolate, ThreadLocalTop* top) = 0;
virtual ~ThreadVisitor() = default;
class ThreadManager {
void Lock();
void Unlock();
void InitThread(const ExecutionAccess&);
void ArchiveThread();
bool RestoreThread();
void FreeThreadResources();
bool IsArchived();
void Iterate(RootVisitor* v);
void IterateArchivedThreads(ThreadVisitor* v);
bool IsLockedByCurrentThread() const {
return mutex_owner_.load(std::memory_order_relaxed) == ThreadId::Current();
bool IsLockedByThread(ThreadId id) const {
return mutex_owner_.load(std::memory_order_relaxed) == id;
ThreadId CurrentId();
// Iterate over in-use states.
ThreadState* FirstThreadStateInUse();
ThreadState* GetFreeThreadState();
explicit ThreadManager(Isolate* isolate);
void DeleteThreadStateList(ThreadState* anchor);
void EagerlyArchiveThread();
base::Mutex mutex_;
// {ThreadId} must be trivially copyable to be stored in {std::atomic}.
std::atomic<ThreadId> mutex_owner_;
ThreadId lazily_archived_thread_;
ThreadState* lazily_archived_thread_state_;
// In the following two lists there is always at least one object on the list.
// The first object is a flying anchor that is only there to simplify linking
// and unlinking.
// Head of linked list of free states.
ThreadState* free_anchor_;
// Head of linked list of states in use.
ThreadState* in_use_anchor_;
Isolate* isolate_;
friend class Isolate;
friend class ThreadState;
} // namespace internal
} // namespace v8