static void lockOrFail(Lock lock, long timeout) ctex {
  ping();
  vmBus_send locking(lock, thread := currentThread());
  if (!lock.tryLock(timeout, TimeUnit.MILLISECONDS)) {
    S s = "Couldn't acquire lock after " + timeout + " ms.";
    if (lock instanceof ReentrantLock) {
      ReentrantLock l = cast lock;
      s += " Hold count: " + l.getHoldCount() + ", owner: " + call(l, "getOwner");
    }
    fail(s);
  }
  vmBus_send locked(lock, thread := currentThread());
  ping();
}