bool DirtyCardQueueSet::mut_process_buffer(void** buf) {

  {- -------------------------------------------
  (1) 
      ---------------------------------------- -}

      // Used to determine if we had already claimed a par_id
      // before entering this method.
      bool already_claimed = false;

      // We grab the current JavaThread.
      JavaThread* thread = JavaThread::current();

      // We get the the number of any par_id that this thread
      // might have already claimed.
      int worker_i = thread->get_claimed_par_id();

      // If worker_i is not -1 then the thread has already claimed
      // a par_id. We make note of it using the already_claimed value
      if (worker_i != -1) {
        already_claimed = true;
      } else {

        // Otherwise we need to claim a par id
        worker_i = _free_ids->claim_par_id();

        // And store the par_id value in the thread
        thread->set_claimed_par_id(worker_i);
      }

      bool b = false;
      if (worker_i != -1) {
        b = DirtyCardQueue::apply_closure_to_buffer(_closure, buf, 0,
                                                    _sz, true, worker_i);
        if (b) Atomic::inc(&_processed_buffers_mut);

        // If we had not claimed an id before entering the method
        // then we must release the id.
        if (!already_claimed) {

          // we release the id
          _free_ids->release_par_id(worker_i);

          // and set the claimed_id in the thread to -1
          thread->set_claimed_par_id(-1);
        }
      }
      return b;
    }