src/share/vm/gc_implementation/concurrentMarkSweep/concurrentMarkSweepGeneration.cpp

*** 3014,3031 ****
        uint n_workers = workers->active_workers();
  
        StrongRootsScope srs(n_workers);
  
        CMSParInitialMarkTask tsk(this, &srs, n_workers);
-       gch->set_par_threads(n_workers);
        initialize_sequential_subtasks_for_young_gen_rescan(n_workers);
        if (n_workers > 1) {
          workers->run_task(&tsk);
        } else {
          tsk.work(0);
        }
-       gch->set_par_threads(0);
      } else {
        // The serial version.
        CLDToOopClosure cld_closure(&notOlder, true);
        gch->rem_set()->prepare_for_younger_refs_iterate(false); // Not parallel.
  
--- 3014,3029 ----
*** 5085,5096 ****
  
    StrongRootsScope srs(n_workers);
  
    CMSParRemarkTask tsk(this, cms_space, n_workers, workers, task_queues(), &srs);
  
-   // Set up for parallel process_roots work.
-   gch->set_par_threads(n_workers);
    // We won't be iterating over the cards in the card table updating
    // the younger_gen cards, so we shouldn't call the following else
    // the verification code as well as subsequent younger_refs_iterate
    // code would get confused. XXX
    // gch->rem_set()->prepare_for_younger_refs_iterate(true); // parallel
--- 5083,5092 ----
*** 5124,5134 ****
    } else {
      ReferenceProcessorMTDiscoveryMutator mt(ref_processor(), false);
      tsk.work(0);
    }
  
-   gch->set_par_threads(0);  // 0 ==> non-parallel.
    // restore, single-threaded for now, any preserved marks
    // as a result of work_q overflow
    restore_preserved_marks_if_any();
  }
  
--- 5120,5129 ----