thread_pool.h

#ifndef _UTILITY_THREAD_POOL_H_
#define _UTILITY_THREAD_POOL_H_
 
#include <pthread.h>
#include <vector>
 
namespace smaug {
 
class ThreadPool {
   public:
    ThreadPool(int nthreads);
    ~ThreadPool();
 
    typedef void* (*WorkerThreadFunc)(void*);
 
    int size() const { return workers.size(); }
 
    void initThreadPool();
 
    int dispatchThread(WorkerThreadFunc func, void* args);
 
    void joinThreadPool();
 
   protected:
    enum ThreadStatus { Uninitialized, Idle, Running };
 
    struct WorkerThread {
        WorkerThreadFunc func;
        void* args;
 
        pthread_t thread;
        pthread_mutex_t statusMutex;
        bool exit;
        bool valid;
        ThreadStatus status;
        pthread_cond_t wakeupCond;
        pthread_cond_t statusCond;
        int cpuid;
 
        WorkerThread() {
            func = NULL;
            args = NULL;
            exit = false;
            valid = false;
            status = Uninitialized;
            pthread_mutex_init(&statusMutex, NULL);
            pthread_cond_init(&wakeupCond, NULL);
            pthread_cond_init(&statusCond, NULL);
        }
    };
 
    struct ThreadInitArgs {
        WorkerThread* worker;
        pthread_mutex_t cpuidMutex;
        pthread_cond_t cpuidCond;
        int cpuid;
 
        ThreadInitArgs(WorkerThread* _worker) : worker(_worker) {
            pthread_mutex_init(&cpuidMutex, NULL);
            pthread_cond_init(&cpuidCond, NULL);
            cpuid = -1;
        }
    };
 
    static void* workerLoop(void* args);
 
    std::vector<WorkerThread> workers;
};
 
}  // namespace smaug
 
#endif