locks.hpp

// ***********************************************************************
//
//            Vite: A C++ library for distributed-memory graph clustering 
//                  using MPI+OpenMP
// 
//               Daniel Chavarria (daniel.chavarria@pnnl.gov)
//               Antonino Tumeo (antonino.tumeo@pnnl.gov)
//               Mahantesh Halappanavar (hala@pnnl.gov)
//               Pacific Northwest National Laboratory	
//
//               Hao Lu (luhowardmark@wsu.edu)
//               Sayan Ghosh (sayan.ghosh@wsu.edu)
//               Ananth Kalyanaraman (ananth@eecs.wsu.edu)
//               Washington State University
//
// ***********************************************************************
//
//       Copyright (2017) Battelle Memorial Institute
//                      All rights reserved.
//
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// ************************************************************************

#ifndef __LOCKS_H
#define __LOCKS_H

#ifdef USE_OPENMP_LOCK
#else
#ifdef USE_SPINLOCK 
#include <atomic>
std::atomic_flag lkd_ = ATOMIC_FLAG_INIT;
#else
#include <mutex>
std::mutex mtx_;
#endif
void lock() {
#ifdef USE_SPINLOCK 
    while (lkd_.test_and_set(std::memory_order_acquire)) { ; } 
#else
    mtx_.lock();
#endif
}
void unlock() { 
#ifdef USE_SPINLOCK 
    lkd_.clear(std::memory_order_release); 
#else
    mtx_.unlock();
#endif
}
#endif

#endif // __LOCKS_H