mp.java

  while (true) {
    // consumer receives next cursor
    // if cursor is >= 0 - thread can use it as ring queue index
    // if cursor == -1 - ring queue is full, thread has a choice to do something else
    // if cursor == -2 - there was CAS failure and thread can retry more eagerly
    // for purpose of this test we busy loop regardless
    long cursor = sequence.next();
    if (cursor < 0) {
      continue;
    }
    int v = queue.get(cursor).value;
    sequence.done(cursor);
  }