75 lines
2.0 KiB
C++
75 lines
2.0 KiB
C++
#ifndef ROMKATV_GITSTATUS_THREAD_POOL_H_
|
|
#define ROMKATV_GITSTATUS_THREAD_POOL_H_
|
|
|
|
#include <condition_variable>
|
|
#include <cstddef>
|
|
#include <cstdint>
|
|
#include <functional>
|
|
#include <mutex>
|
|
#include <queue>
|
|
#include <thread>
|
|
#include <tuple>
|
|
#include <utility>
|
|
|
|
#include "time.h"
|
|
|
|
namespace gitstatus {
|
|
|
|
class ThreadPool {
|
|
public:
|
|
explicit ThreadPool(size_t num_threads);
|
|
ThreadPool(ThreadPool&&) = delete;
|
|
|
|
// Waits for the currently running functions to finish.
|
|
// Does NOT wait for the queue of functions to drain.
|
|
// If you want the latter, call Wait() manually.
|
|
~ThreadPool();
|
|
|
|
// Runs `f` on one of the threads at or after time `t`. Can be called
|
|
// from any thread. Can be called concurrently.
|
|
//
|
|
// Does not block.
|
|
void Schedule(Time t, std::function<void()> f);
|
|
|
|
void Schedule(std::function<void()> f) { Schedule(Clock::now(), std::move(f)); }
|
|
|
|
// Blocks until the work queue is empty and there are no currently
|
|
// running functions.
|
|
void Wait();
|
|
|
|
size_t num_threads() const { return threads_.size(); }
|
|
|
|
private:
|
|
struct Work {
|
|
bool operator<(const Work& w) const { return std::tie(w.t, w.idx) < std::tie(t, idx); }
|
|
Time t;
|
|
int64_t idx;
|
|
mutable std::function<void()> f;
|
|
};
|
|
|
|
void Loop(size_t tid);
|
|
|
|
int64_t last_idx_ = 0;
|
|
int64_t num_inflight_;
|
|
bool exit_ = false;
|
|
// Do we have a thread waiting on sleeper_cv_?
|
|
bool have_sleeper_ = false;
|
|
std::mutex mutex_;
|
|
// Any number of threads can wait on this condvar. Always without a timeout.
|
|
std::condition_variable cv_;
|
|
// At most one thread can wait on this condvar at a time. Always with a timeout.
|
|
std::condition_variable sleeper_cv_;
|
|
// Signalled when the work queue is empty and there is nothing inflight.
|
|
std::condition_variable idle_cv_;
|
|
std::priority_queue<Work> work_;
|
|
std::vector<std::thread> threads_;
|
|
};
|
|
|
|
void InitGlobalThreadPool(size_t num_threads);
|
|
|
|
ThreadPool* GlobalThreadPool();
|
|
|
|
} // namespace gitstatus
|
|
|
|
#endif // ROMKATV_GITSTATUS_THREAD_POOL_H_
|