void SafepointSynchronize::update_statistics_on_spin_end() {

  {- -------------------------------------------
  (1) _safepoint_stats[_cur_stat_index] に入っている統計情報を更新する.
      ---------------------------------------- -}

      SafepointStats *spstat = &_safepoint_stats[_cur_stat_index];

      jlong cur_time = os::javaTimeNanos();

      spstat->_nof_threads_wait_to_block = _waiting_to_block;
      if (spstat->_nof_initial_running_threads != 0) {
        spstat->_time_to_spin = cur_time - spstat->_time_to_spin;
      }

      if (need_to_track_page_armed_status) {
        spstat->_page_armed = (PageArmed == 1);
      }

      // Records the start time of waiting for to block. Updated when block is done.
      if (_waiting_to_block != 0) {
        spstat->_time_to_wait_to_block = cur_time;
      } else {
        spstat->_time_to_wait_to_block = 0;
      }
    }