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#include "node_worker.h"
#include "debug_utils.h"
#include "node_errors.h"
#include "node_internals.h"
#include "node_buffer.h"
#include "node_perf.h"
#include "util.h"
#include "util-inl.h"
#include "async_wrap.h"
#include "async_wrap-inl.h"
#include <string>
using v8::ArrayBuffer;
using v8::Context;
using v8::Function;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::HandleScope;
using v8::Integer;
using v8::Isolate;
using v8::Local;
using v8::Locker;
using v8::Number;
using v8::Object;
using v8::SealHandleScope;
using v8::String;
using v8::Value;
namespace node {
namespace worker {
namespace {
uint64_t next_thread_id = 1;
Mutex next_thread_id_mutex;
} // anonymous namespace
Worker::Worker(Environment* env, Local<Object> wrap)
: AsyncWrap(env, wrap, AsyncWrap::PROVIDER_WORKER) {
// Generate a new thread id.
{
Mutex::ScopedLock next_thread_id_lock(next_thread_id_mutex);
thread_id_ = next_thread_id++;
}
Debug(this, "Creating worker with id %llu", thread_id_);
wrap->Set(env->context(),
env->thread_id_string(),
Number::New(env->isolate(),
static_cast<double>(thread_id_))).FromJust();
// Set up everything that needs to be set up in the parent environment.
parent_port_ = MessagePort::New(env, env->context());
if (parent_port_ == nullptr) {
// This can happen e.g. because execution is terminating.
return;
}
child_port_data_.reset(new MessagePortData(nullptr));
MessagePort::Entangle(parent_port_, child_port_data_.get());
object()->Set(env->context(),
env->message_port_string(),
parent_port_->object()).FromJust();
array_buffer_allocator_.reset(CreateArrayBufferAllocator());
CHECK_EQ(uv_loop_init(&loop_), 0);
isolate_ = NewIsolate(array_buffer_allocator_.get(), &loop_);
CHECK_NE(isolate_, nullptr);
thread_exit_async_.reset(new uv_async_t);
thread_exit_async_->data = this;
CHECK_EQ(uv_async_init(env->event_loop(),
thread_exit_async_.get(),
[](uv_async_t* handle) {
static_cast<Worker*>(handle->data)->OnThreadStopped();
}), 0);
{
// Enter an environment capable of executing code in the child Isolate
// (and only in it).
Locker locker(isolate_);
Isolate::Scope isolate_scope(isolate_);
HandleScope handle_scope(isolate_);
isolate_data_.reset(CreateIsolateData(isolate_,
&loop_,
env->isolate_data()->platform(),
array_buffer_allocator_.get()));
CHECK(isolate_data_);
Local<Context> context = NewContext(isolate_);
Context::Scope context_scope(context);
// TODO(addaleax): Use CreateEnvironment(), or generally another public API.
env_.reset(new Environment(isolate_data_.get(),
context,
nullptr));
CHECK_NE(env_, nullptr);
env_->set_abort_on_uncaught_exception(false);
env_->set_worker_context(this);
env_->set_thread_id(thread_id_);
env_->Start(std::vector<std::string>{},
std::vector<std::string>{},
env->profiler_idle_notifier_started());
}
// The new isolate won't be bothered on this thread again.
isolate_->DiscardThreadSpecificMetadata();
Debug(this, "Set up worker with id %llu", thread_id_);
}
bool Worker::is_stopped() const {
Mutex::ScopedLock stopped_lock(stopped_mutex_);
return stopped_;
}
void Worker::Run() {
std::string name = "WorkerThread ";
name += std::to_string(thread_id_);
TRACE_EVENT_METADATA1(
"__metadata", "thread_name", "name",
TRACE_STR_COPY(name.c_str()));
MultiIsolatePlatform* platform = isolate_data_->platform();
CHECK_NE(platform, nullptr);
Debug(this, "Starting worker with id %llu", thread_id_);
{
Locker locker(isolate_);
Isolate::Scope isolate_scope(isolate_);
SealHandleScope outer_seal(isolate_);
{
Context::Scope context_scope(env_->context());
HandleScope handle_scope(isolate_);
{
HandleScope handle_scope(isolate_);
Mutex::ScopedLock lock(mutex_);
// Set up the message channel for receiving messages in the child.
child_port_ = MessagePort::New(env_.get(),
env_->context(),
std::move(child_port_data_));
// MessagePort::New() may return nullptr if execution is terminated
// within it.
if (child_port_ != nullptr)
env_->set_message_port(child_port_->object(isolate_));
Debug(this, "Created message port for worker %llu", thread_id_);
}
if (!is_stopped()) {
HandleScope handle_scope(isolate_);
Environment::AsyncCallbackScope callback_scope(env_.get());
env_->async_hooks()->push_async_ids(1, 0);
// This loads the Node bootstrapping code.
LoadEnvironment(env_.get());
env_->async_hooks()->pop_async_id(1);
Debug(this, "Loaded environment for worker %llu", thread_id_);
}
{
SealHandleScope seal(isolate_);
bool more;
env_->performance_state()->Mark(
node::performance::NODE_PERFORMANCE_MILESTONE_LOOP_START);
do {
if (is_stopped()) break;
uv_run(&loop_, UV_RUN_DEFAULT);
if (is_stopped()) break;
platform->DrainTasks(isolate_);
more = uv_loop_alive(&loop_);
if (more && !is_stopped())
continue;
EmitBeforeExit(env_.get());
// Emit `beforeExit` if the loop became alive either after emitting
// event, or after running some callbacks.
more = uv_loop_alive(&loop_);
} while (more == true);
env_->performance_state()->Mark(
node::performance::NODE_PERFORMANCE_MILESTONE_LOOP_EXIT);
}
}
{
int exit_code;
bool stopped = is_stopped();
if (!stopped)
exit_code = EmitExit(env_.get());
Mutex::ScopedLock lock(mutex_);
if (exit_code_ == 0 && !stopped)
exit_code_ = exit_code;
Debug(this, "Exiting thread for worker %llu with exit code %d",
thread_id_, exit_code_);
}
env_->set_can_call_into_js(false);
Isolate::DisallowJavascriptExecutionScope disallow_js(isolate_,
Isolate::DisallowJavascriptExecutionScope::THROW_ON_FAILURE);
// Grab the parent-to-child channel and render is unusable.
MessagePort* child_port;
{
Mutex::ScopedLock lock(mutex_);
child_port = child_port_;
child_port_ = nullptr;
}
{
Context::Scope context_scope(env_->context());
child_port->Close();
env_->stop_sub_worker_contexts();
env_->RunCleanup();
RunAtExit(env_.get());
{
Mutex::ScopedLock stopped_lock(stopped_mutex_);
stopped_ = true;
}
env_->RunCleanup();
// This call needs to be made while the `Environment` is still alive
// because we assume that it is available for async tracking in the
// NodePlatform implementation.
platform->DrainTasks(isolate_);
}
env_.reset();
}
DisposeIsolate();
// Need to run the loop one more time to close the platform's uv_async_t
uv_run(&loop_, UV_RUN_ONCE);
{
Mutex::ScopedLock lock(mutex_);
CHECK(thread_exit_async_);
scheduled_on_thread_stopped_ = true;
uv_async_send(thread_exit_async_.get());
}
Debug(this, "Worker %llu thread stops", thread_id_);
}
void Worker::DisposeIsolate() {
if (isolate_ == nullptr)
return;
Debug(this, "Worker %llu dispose isolate", thread_id_);
CHECK(isolate_data_);
MultiIsolatePlatform* platform = isolate_data_->platform();
platform->CancelPendingDelayedTasks(isolate_);
isolate_data_.reset();
platform->UnregisterIsolate(isolate_);
isolate_->Dispose();
isolate_ = nullptr;
}
void Worker::JoinThread() {
if (thread_joined_)
return;
CHECK_EQ(uv_thread_join(&tid_), 0);
thread_joined_ = true;
env()->remove_sub_worker_context(this);
if (thread_exit_async_) {
env()->CloseHandle(thread_exit_async_.release(), [](uv_async_t* async) {
delete async;
});
if (scheduled_on_thread_stopped_)
OnThreadStopped();
}
}
void Worker::OnThreadStopped() {
{
Mutex::ScopedLock lock(mutex_);
scheduled_on_thread_stopped_ = false;
Debug(this, "Worker %llu thread stopped", thread_id_);
{
Mutex::ScopedLock stopped_lock(stopped_mutex_);
CHECK(stopped_);
}
CHECK_EQ(child_port_, nullptr);
parent_port_ = nullptr;
}
JoinThread();
{
HandleScope handle_scope(env()->isolate());
Context::Scope context_scope(env()->context());
// Reset the parent port as we're closing it now anyway.
object()->Set(env()->context(),
env()->message_port_string(),
Undefined(env()->isolate())).FromJust();
Local<Value> code = Integer::New(env()->isolate(), exit_code_);
MakeCallback(env()->onexit_string(), 1, &code);
}
// JoinThread() cleared all libuv handles bound to this Worker,
// the C++ object is no longer needed for anything now.
MakeWeak();
}
Worker::~Worker() {
Mutex::ScopedLock lock(mutex_);
JoinThread();
CHECK(stopped_);
CHECK(thread_joined_);
CHECK_EQ(child_port_, nullptr);
CheckedUvLoopClose(&loop_);
// This has most likely already happened within the worker thread -- this
// is just in case Worker creation failed early.
DisposeIsolate();
Debug(this, "Worker %llu destroyed", thread_id_);
}
void Worker::New(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args.IsConstructCall());
if (env->isolate_data()->platform() == nullptr) {
THROW_ERR_MISSING_PLATFORM_FOR_WORKER(env);
return;
}
new Worker(env, args.This());
}
void Worker::StartThread(const FunctionCallbackInfo<Value>& args) {
Worker* w;
ASSIGN_OR_RETURN_UNWRAP(&w, args.This());
Mutex::ScopedLock lock(w->mutex_);
w->env()->add_sub_worker_context(w);
w->stopped_ = false;
CHECK_EQ(uv_thread_create(&w->tid_, [](void* arg) {
static_cast<Worker*>(arg)->Run();
}, static_cast<void*>(w)), 0);
w->thread_joined_ = false;
}
void Worker::StopThread(const FunctionCallbackInfo<Value>& args) {
Worker* w;
ASSIGN_OR_RETURN_UNWRAP(&w, args.This());
Debug(w, "Worker %llu is getting stopped by parent", w->thread_id_);
w->Exit(1);
w->JoinThread();
}
void Worker::Ref(const FunctionCallbackInfo<Value>& args) {
Worker* w;
ASSIGN_OR_RETURN_UNWRAP(&w, args.This());
if (w->thread_exit_async_)
uv_ref(reinterpret_cast<uv_handle_t*>(w->thread_exit_async_.get()));
}
void Worker::Unref(const FunctionCallbackInfo<Value>& args) {
Worker* w;
ASSIGN_OR_RETURN_UNWRAP(&w, args.This());
if (w->thread_exit_async_)
uv_unref(reinterpret_cast<uv_handle_t*>(w->thread_exit_async_.get()));
}
void Worker::Exit(int code) {
Mutex::ScopedLock lock(mutex_);
Mutex::ScopedLock stopped_lock(stopped_mutex_);
Debug(this, "Worker %llu called Exit(%d)", thread_id_, code);
if (!stopped_) {
CHECK_NE(env_, nullptr);
stopped_ = true;
exit_code_ = code;
if (child_port_ != nullptr)
child_port_->StopEventLoop();
isolate_->TerminateExecution();
}
}
namespace {
// Return the MessagePort that is global for this Environment and communicates
// with the internal [kPort] port of the JS Worker class in the parent thread.
void GetEnvMessagePort(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
Local<Object> port = env->message_port();
if (!port.IsEmpty()) {
CHECK_EQ(port->CreationContext()->GetIsolate(), args.GetIsolate());
args.GetReturnValue().Set(port);
}
}
void InitWorker(Local<Object> target,
Local<Value> unused,
Local<Context> context,
void* priv) {
Environment* env = Environment::GetCurrent(context);
{
Local<FunctionTemplate> w = env->NewFunctionTemplate(Worker::New);
w->InstanceTemplate()->SetInternalFieldCount(1);
AsyncWrap::AddWrapMethods(env, w);
env->SetProtoMethod(w, "startThread", Worker::StartThread);
env->SetProtoMethod(w, "stopThread", Worker::StopThread);
env->SetProtoMethod(w, "ref", Worker::Ref);
env->SetProtoMethod(w, "unref", Worker::Unref);
Local<String> workerString =
FIXED_ONE_BYTE_STRING(env->isolate(), "Worker");
w->SetClassName(workerString);
target->Set(workerString, w->GetFunction());
}
env->SetMethod(target, "getEnvMessagePort", GetEnvMessagePort);
auto thread_id_string = FIXED_ONE_BYTE_STRING(env->isolate(), "threadId");
target->Set(env->context(),
thread_id_string,
Number::New(env->isolate(),
static_cast<double>(env->thread_id()))).FromJust();
}
} // anonymous namespace
} // namespace worker
} // namespace node
NODE_MODULE_CONTEXT_AWARE_INTERNAL(worker, node::worker::InitWorker)
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