Mutex implementation with no spinlocks

mutex_nowait.py

def wait():
  condmut.acquire()
  sleepQueue.enqueue(P)
  condmut.release()
  sleep(P)

def signal():
  condmut.acquire()
  P = sleepQueue.dequeue(NoWait)
  if not P:
    return -1
  signal(P)
  condmut.release()

def wait():
  mutex.acquire()
  if deactivate:
    mutex.release()
    perform()
  else:
    in_count += 1
    mutex.release()
    x.wait()
    auxmut.acquire()
    out_count += 1
    auxmut.release()
    if deactivate:
      perform()

def abort():
  mutex.acquire()
  deactivate = true
  while out_count < in_count:
    x.signal()
  mutex.release()