yuzu/src/common/thread_worker.h

115 lines
3.3 KiB
C++

// Copyright 2020 yuzu emulator team
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <atomic>
#include <functional>
#include <mutex>
#include <string>
#include <type_traits>
#include <vector>
#include <queue>
#include "common/thread.h"
#include "common/unique_function.h"
namespace Common {
template <class StateType = void>
class StatefulThreadWorker {
static constexpr bool with_state = !std::is_same_v<StateType, void>;
struct DummyCallable {
int operator()() const noexcept {
return 0;
}
};
using Task =
std::conditional_t<with_state, UniqueFunction<void, StateType*>, UniqueFunction<void>>;
using StateMaker = std::conditional_t<with_state, std::function<StateType()>, DummyCallable>;
public:
explicit StatefulThreadWorker(size_t num_workers, std::string name, StateMaker func = {})
: workers_queued{num_workers}, thread_name{std::move(name)} {
const auto lambda = [this, func] {
Common::SetCurrentThreadName(thread_name.c_str());
{
std::conditional_t<with_state, StateType, int> state{func()};
while (!stop) {
Task task;
{
std::unique_lock lock{queue_mutex};
if (requests.empty()) {
wait_condition.notify_all();
}
condition.wait(lock, [this] { return stop || !requests.empty(); });
if (stop) {
break;
}
task = std::move(requests.front());
requests.pop();
}
if constexpr (with_state) {
task(&state);
} else {
task();
}
++work_done;
}
}
++workers_stopped;
wait_condition.notify_all();
};
for (size_t i = 0; i < num_workers; ++i) {
threads.emplace_back(lambda);
}
}
~StatefulThreadWorker() {
{
std::unique_lock lock{queue_mutex};
stop = true;
}
condition.notify_all();
for (std::thread& thread : threads) {
thread.join();
}
}
void QueueWork(Task work) {
{
std::unique_lock lock{queue_mutex};
requests.emplace(std::move(work));
++work_scheduled;
}
condition.notify_one();
}
void WaitForRequests() {
std::unique_lock lock{queue_mutex};
wait_condition.wait(lock, [this] {
return workers_stopped >= workers_queued || work_done >= work_scheduled;
});
}
private:
std::vector<std::thread> threads;
std::queue<Task> requests;
std::mutex queue_mutex;
std::condition_variable condition;
std::condition_variable wait_condition;
std::atomic_bool stop{};
std::atomic<size_t> work_scheduled{};
std::atomic<size_t> work_done{};
std::atomic<size_t> workers_stopped{};
std::atomic<size_t> workers_queued{};
std::string thread_name;
};
using ThreadWorker = StatefulThreadWorker<>;
} // namespace Common