src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp

rev 57380 : 8234974: Shenandoah: Do concurrent roots even when no evacuation is necessary

*** 540,549 ****
--- 540,550 ----
    if (is_update_refs_in_progress())          st->print("updating refs, ");
    if (is_concurrent_traversal_in_progress()) st->print("traversal, ");
    if (is_degenerated_gc_in_progress())       st->print("degenerated gc, ");
    if (is_full_gc_in_progress())              st->print("full gc, ");
    if (is_full_gc_move_in_progress())         st->print("full gc move, ");
+   if (is_concurrent_root_in_progress())      st->print("concurrent roots, ");
  
    if (cancelled_gc()) {
      st->print("cancelled");
    } else {
      st->print("not cancelled");
*** 1538,1547 ****
--- 1539,1553 ----
        heuristics()->choose_collection_set(_collection_set);
  
        _free_set->rebuild();
      }
  
+     if (!is_degenerated_gc_in_progress()) {
+       prepare_concurrent_roots();
+       prepare_concurrent_unloading();
+     }
+ 
      // If collection set has candidates, start evacuation.
      // Otherwise, bypass the rest of the cycle.
      if (!collection_set()->is_empty()) {
        ShenandoahGCPhase init_evac(ShenandoahPhaseTimings::init_evac);
  
*** 1552,1563 ****
        set_evacuation_in_progress(true);
        // From here on, we need to update references.
        set_has_forwarded_objects(true);
  
        if (!is_degenerated_gc_in_progress()) {
!         prepare_concurrent_roots();
!         prepare_concurrent_unloading();
          evacuate_and_update_roots();
        }
  
        if (ShenandoahPacing) {
          pacer()->setup_for_evac();
--- 1558,1570 ----
        set_evacuation_in_progress(true);
        // From here on, we need to update references.
        set_has_forwarded_objects(true);
  
        if (!is_degenerated_gc_in_progress()) {
!         if (ShenandoahConcurrentRoots::should_do_concurrent_class_unloading()) {
!           ShenandoahCodeRoots::arm_nmethods();
!         }
          evacuate_and_update_roots();
        }
  
        if (ShenandoahPacing) {
          pacer()->setup_for_evac();
*** 1667,1677 ****
      }
    }
  };
  
  void ShenandoahHeap::op_roots() {
!   if (is_evacuation_in_progress()) {
      if (ShenandoahConcurrentRoots::should_do_concurrent_class_unloading()) {
        _unloader.unload();
      }
  
      if (ShenandoahConcurrentRoots::should_do_concurrent_roots()) {
--- 1674,1684 ----
      }
    }
  };
  
  void ShenandoahHeap::op_roots() {
!   if (is_concurrent_root_in_progress()) {
      if (ShenandoahConcurrentRoots::should_do_concurrent_class_unloading()) {
        _unloader.unload();
      }
  
      if (ShenandoahConcurrentRoots::should_do_concurrent_roots()) {
*** 2233,2243 ****
  }
  
  void ShenandoahHeap::prepare_concurrent_unloading() {
    assert(SafepointSynchronize::is_at_safepoint(), "Must be at a safepoint");
    if (ShenandoahConcurrentRoots::should_do_concurrent_class_unloading()) {
-     ShenandoahCodeRoots::prepare_concurrent_unloading();
      _unloader.prepare();
    }
  }
  
  void ShenandoahHeap::finish_concurrent_unloading() {
--- 2240,2249 ----