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#include "node_platform.h"
#include "node_internals.h"
#include "env.h"
#include "env-inl.h"
#include "util.h"
#include <algorithm>
namespace node {
using v8::HandleScope;
using v8::Isolate;
using v8::Local;
using v8::Object;
using v8::Platform;
using v8::Task;
using v8::TracingController;
static void BackgroundRunner(void* data) {
TRACE_EVENT_METADATA1("__metadata", "thread_name", "name",
"BackgroundTaskRunner");
TaskQueue<Task> *background_tasks = static_cast<TaskQueue<Task> *>(data);
while (std::unique_ptr<Task> task = background_tasks->BlockingPop()) {
task->Run();
background_tasks->NotifyOfCompletion();
}
}
BackgroundTaskRunner::BackgroundTaskRunner(int thread_pool_size) {
for (int i = 0; i < thread_pool_size; i++) {
std::unique_ptr<uv_thread_t> t { new uv_thread_t() };
if (uv_thread_create(t.get(), BackgroundRunner, &background_tasks_) != 0)
break;
threads_.push_back(std::move(t));
}
}
void BackgroundTaskRunner::PostTask(std::unique_ptr<Task> task) {
background_tasks_.Push(std::move(task));
}
void BackgroundTaskRunner::PostIdleTask(std::unique_ptr<v8::IdleTask> task) {
UNREACHABLE();
}
void BackgroundTaskRunner::PostDelayedTask(std::unique_ptr<v8::Task> task,
double delay_in_seconds) {
UNREACHABLE();
}
void BackgroundTaskRunner::BlockingDrain() {
background_tasks_.BlockingDrain();
}
void BackgroundTaskRunner::Shutdown() {
background_tasks_.Stop();
for (size_t i = 0; i < threads_.size(); i++) {
CHECK_EQ(0, uv_thread_join(threads_[i].get()));
}
}
size_t BackgroundTaskRunner::NumberOfAvailableBackgroundThreads() const {
return threads_.size();
}
PerIsolatePlatformData::PerIsolatePlatformData(
v8::Isolate* isolate, uv_loop_t* loop)
: loop_(loop) {
flush_tasks_ = new uv_async_t();
CHECK_EQ(0, uv_async_init(loop, flush_tasks_, FlushTasks));
flush_tasks_->data = static_cast<void*>(this);
uv_unref(reinterpret_cast<uv_handle_t*>(flush_tasks_));
}
void PerIsolatePlatformData::FlushTasks(uv_async_t* handle) {
auto platform_data = static_cast<PerIsolatePlatformData*>(handle->data);
platform_data->FlushForegroundTasksInternal();
}
void PerIsolatePlatformData::PostIdleTask(std::unique_ptr<v8::IdleTask> task) {
UNREACHABLE();
}
void PerIsolatePlatformData::PostTask(std::unique_ptr<Task> task) {
CHECK_NE(flush_tasks_, nullptr);
foreground_tasks_.Push(std::move(task));
uv_async_send(flush_tasks_);
}
void PerIsolatePlatformData::PostDelayedTask(
std::unique_ptr<Task> task, double delay_in_seconds) {
CHECK_NE(flush_tasks_, nullptr);
std::unique_ptr<DelayedTask> delayed(new DelayedTask());
delayed->task = std::move(task);
delayed->platform_data = shared_from_this();
delayed->timeout = delay_in_seconds;
foreground_delayed_tasks_.Push(std::move(delayed));
uv_async_send(flush_tasks_);
}
PerIsolatePlatformData::~PerIsolatePlatformData() {
Shutdown();
}
void PerIsolatePlatformData::Shutdown() {
if (flush_tasks_ == nullptr)
return;
while (FlushForegroundTasksInternal()) {}
CancelPendingDelayedTasks();
uv_close(reinterpret_cast<uv_handle_t*>(flush_tasks_),
[](uv_handle_t* handle) {
delete reinterpret_cast<uv_async_t*>(handle);
});
flush_tasks_ = nullptr;
}
void PerIsolatePlatformData::ref() {
ref_count_++;
}
int PerIsolatePlatformData::unref() {
return --ref_count_;
}
NodePlatform::NodePlatform(int thread_pool_size,
TracingController* tracing_controller) {
if (tracing_controller) {
tracing_controller_.reset(tracing_controller);
} else {
TracingController* controller = new TracingController();
tracing_controller_.reset(controller);
}
background_task_runner_ =
std::make_shared<BackgroundTaskRunner>(thread_pool_size);
}
void NodePlatform::RegisterIsolate(IsolateData* isolate_data, uv_loop_t* loop) {
Isolate* isolate = isolate_data->isolate();
Mutex::ScopedLock lock(per_isolate_mutex_);
std::shared_ptr<PerIsolatePlatformData> existing = per_isolate_[isolate];
if (existing) {
existing->ref();
} else {
per_isolate_[isolate] =
std::make_shared<PerIsolatePlatformData>(isolate, loop);
}
}
void NodePlatform::UnregisterIsolate(IsolateData* isolate_data) {
Isolate* isolate = isolate_data->isolate();
Mutex::ScopedLock lock(per_isolate_mutex_);
std::shared_ptr<PerIsolatePlatformData> existing = per_isolate_[isolate];
CHECK(existing);
if (existing->unref() == 0) {
existing->Shutdown();
per_isolate_.erase(isolate);
}
}
void NodePlatform::Shutdown() {
background_task_runner_->Shutdown();
{
Mutex::ScopedLock lock(per_isolate_mutex_);
per_isolate_.clear();
}
}
size_t NodePlatform::NumberOfAvailableBackgroundThreads() {
return background_task_runner_->NumberOfAvailableBackgroundThreads();
}
void PerIsolatePlatformData::RunForegroundTask(std::unique_ptr<Task> task) {
Isolate* isolate = Isolate::GetCurrent();
HandleScope scope(isolate);
Environment* env = Environment::GetCurrent(isolate);
InternalCallbackScope cb_scope(env, Local<Object>(), { 0, 0 },
InternalCallbackScope::kAllowEmptyResource);
task->Run();
}
void PerIsolatePlatformData::DeleteFromScheduledTasks(DelayedTask* task) {
auto it = std::find_if(scheduled_delayed_tasks_.begin(),
scheduled_delayed_tasks_.end(),
[task](const DelayedTaskPointer& delayed) -> bool {
return delayed.get() == task;
});
CHECK_NE(it, scheduled_delayed_tasks_.end());
scheduled_delayed_tasks_.erase(it);
}
void PerIsolatePlatformData::RunForegroundTask(uv_timer_t* handle) {
DelayedTask* delayed = static_cast<DelayedTask*>(handle->data);
RunForegroundTask(std::move(delayed->task));
delayed->platform_data->DeleteFromScheduledTasks(delayed);
}
void PerIsolatePlatformData::CancelPendingDelayedTasks() {
scheduled_delayed_tasks_.clear();
}
void NodePlatform::DrainBackgroundTasks(Isolate* isolate) {
std::shared_ptr<PerIsolatePlatformData> per_isolate = ForIsolate(isolate);
do {
// Right now, there is no way to drain only background tasks associated
// with a specific isolate, so this sometimes does more work than
// necessary. In the long run, that functionality is probably going to
// be available anyway, though.
background_task_runner_->BlockingDrain();
} while (per_isolate->FlushForegroundTasksInternal());
}
bool PerIsolatePlatformData::FlushForegroundTasksInternal() {
bool did_work = false;
while (std::unique_ptr<DelayedTask> delayed =
foreground_delayed_tasks_.Pop()) {
did_work = true;
uint64_t delay_millis =
static_cast<uint64_t>(delayed->timeout + 0.5) * 1000;
delayed->timer.data = static_cast<void*>(delayed.get());
uv_timer_init(loop_, &delayed->timer);
// Timers may not guarantee queue ordering of events with the same delay if
// the delay is non-zero. This should not be a problem in practice.
uv_timer_start(&delayed->timer, RunForegroundTask, delay_millis, 0);
uv_unref(reinterpret_cast<uv_handle_t*>(&delayed->timer));
scheduled_delayed_tasks_.emplace_back(delayed.release(),
[](DelayedTask* delayed) {
uv_close(reinterpret_cast<uv_handle_t*>(&delayed->timer),
[](uv_handle_t* handle) {
delete static_cast<DelayedTask*>(handle->data);
});
});
}
// Move all foreground tasks into a separate queue and flush that queue.
// This way tasks that are posted while flushing the queue will be run on the
// next call of FlushForegroundTasksInternal.
std::queue<std::unique_ptr<Task>> tasks = foreground_tasks_.PopAll();
while (!tasks.empty()) {
std::unique_ptr<Task> task = std::move(tasks.front());
tasks.pop();
did_work = true;
RunForegroundTask(std::move(task));
}
return did_work;
}
void NodePlatform::CallOnBackgroundThread(Task* task,
ExpectedRuntime expected_runtime) {
background_task_runner_->PostTask(std::unique_ptr<Task>(task));
}
std::shared_ptr<PerIsolatePlatformData>
NodePlatform::ForIsolate(Isolate* isolate) {
Mutex::ScopedLock lock(per_isolate_mutex_);
std::shared_ptr<PerIsolatePlatformData> data = per_isolate_[isolate];
CHECK(data);
return data;
}
void NodePlatform::CallOnForegroundThread(Isolate* isolate, Task* task) {
ForIsolate(isolate)->PostTask(std::unique_ptr<Task>(task));
}
void NodePlatform::CallDelayedOnForegroundThread(Isolate* isolate,
Task* task,
double delay_in_seconds) {
ForIsolate(isolate)->PostDelayedTask(
std::unique_ptr<Task>(task), delay_in_seconds);
}
bool NodePlatform::FlushForegroundTasks(v8::Isolate* isolate) {
return ForIsolate(isolate)->FlushForegroundTasksInternal();
}
void NodePlatform::CancelPendingDelayedTasks(v8::Isolate* isolate) {
ForIsolate(isolate)->CancelPendingDelayedTasks();
}
bool NodePlatform::IdleTasksEnabled(Isolate* isolate) { return false; }
std::shared_ptr<v8::TaskRunner>
NodePlatform::GetBackgroundTaskRunner(Isolate* isolate) {
return background_task_runner_;
}
std::shared_ptr<v8::TaskRunner>
NodePlatform::GetForegroundTaskRunner(Isolate* isolate) {
return ForIsolate(isolate);
}
double NodePlatform::MonotonicallyIncreasingTime() {
// Convert nanos to seconds.
return uv_hrtime() / 1e9;
}
double NodePlatform::CurrentClockTimeMillis() {
return SystemClockTimeMillis();
}
TracingController* NodePlatform::GetTracingController() {
return tracing_controller_.get();
}
template <class T>
TaskQueue<T>::TaskQueue()
: lock_(), tasks_available_(), tasks_drained_(),
outstanding_tasks_(0), stopped_(false), task_queue_() { }
template <class T>
void TaskQueue<T>::Push(std::unique_ptr<T> task) {
Mutex::ScopedLock scoped_lock(lock_);
outstanding_tasks_++;
task_queue_.push(std::move(task));
tasks_available_.Signal(scoped_lock);
}
template <class T>
std::unique_ptr<T> TaskQueue<T>::Pop() {
Mutex::ScopedLock scoped_lock(lock_);
if (task_queue_.empty()) {
return std::unique_ptr<T>(nullptr);
}
std::unique_ptr<T> result = std::move(task_queue_.front());
task_queue_.pop();
return result;
}
template <class T>
std::unique_ptr<T> TaskQueue<T>::BlockingPop() {
Mutex::ScopedLock scoped_lock(lock_);
while (task_queue_.empty() && !stopped_) {
tasks_available_.Wait(scoped_lock);
}
if (stopped_) {
return std::unique_ptr<T>(nullptr);
}
std::unique_ptr<T> result = std::move(task_queue_.front());
task_queue_.pop();
return result;
}
template <class T>
void TaskQueue<T>::NotifyOfCompletion() {
Mutex::ScopedLock scoped_lock(lock_);
if (--outstanding_tasks_ == 0) {
tasks_drained_.Broadcast(scoped_lock);
}
}
template <class T>
void TaskQueue<T>::BlockingDrain() {
Mutex::ScopedLock scoped_lock(lock_);
while (outstanding_tasks_ > 0) {
tasks_drained_.Wait(scoped_lock);
}
}
template <class T>
void TaskQueue<T>::Stop() {
Mutex::ScopedLock scoped_lock(lock_);
stopped_ = true;
tasks_available_.Broadcast(scoped_lock);
}
template <class T>
std::queue<std::unique_ptr<T>> TaskQueue<T>::PopAll() {
Mutex::ScopedLock scoped_lock(lock_);
std::queue<std::unique_ptr<T>> result;
result.swap(task_queue_);
return result;
}
} // namespace node
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