RFR: Fix TestUnifiedLoggingSwitchStress test failure

[Aleksey Shipilev]

On 06/01/2018 05:20 PM, Zhengyu Gu wrote:
> The test failed due to degenerated cycle, which takes over task queue from earlier cycle. Resetting
> task queue statistics under these circumstances, results assertion failures during print_statistics().
> 
> Webrev: http://cr.openjdk.java.net/~zgu/shenandoah/degen_tq_stats/webrev.00/

What is the assert? Maybe we should do what G1 is doing, namely:

  TASKQUEUE_STATS_ONLY(print_taskqueue_stats());
  TASKQUEUE_STATS_ONLY(reset_taskqueue_stats());

If we still need to do what you suggest, I think we are better off using the multiline-version:

#if TASKQUEUE_STATS
  // Do not reset task queue statistics if we are carrying over work
  // in the task queues
  if (!sh->is_degenerated_gc_in_progress()) {
    reset_taskqueue_stats();
  }
#endif

Thanks,
-Aleksey