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

rev 59240 : 8244759: Shenandoah: print verbose class unloading counters
Reviewed-by: XXX

*** 35,44 ****
--- 35,45 ----
  #include "gc/shenandoah/shenandoahCodeRoots.hpp"
  #include "gc/shenandoah/shenandoahConcurrentRoots.hpp"
  #include "gc/shenandoah/shenandoahHeap.inline.hpp"
  #include "gc/shenandoah/shenandoahNMethod.inline.hpp"
  #include "gc/shenandoah/shenandoahLock.hpp"
+ #include "gc/shenandoah/shenandoahPhaseTimings.hpp"
  #include "gc/shenandoah/shenandoahRootProcessor.hpp"
  #include "gc/shenandoah/shenandoahUnload.hpp"
  #include "gc/shenandoah/shenandoahVerifier.hpp"
  #include "memory/iterator.hpp"
  #include "memory/resourceArea.hpp"
*** 133,187 ****
    assert(ShenandoahConcurrentRoots::can_do_concurrent_class_unloading(), "Sanity");
    CodeCache::increment_unloading_cycle();
    DependencyContext::cleaning_start();
  }
  
- void ShenandoahUnload::unlink() {
-   SuspendibleThreadSetJoiner sts;
-   bool unloading_occurred;
-   ShenandoahHeap* const heap = ShenandoahHeap::heap();
-   {
-     MutexLocker cldg_ml(ClassLoaderDataGraph_lock);
-     unloading_occurred = SystemDictionary::do_unloading(heap->gc_timer());
-   }
- 
-   Klass::clean_weak_klass_links(unloading_occurred);
-   ShenandoahCodeRoots::unlink(ShenandoahHeap::heap()->workers(), unloading_occurred);
-   DependencyContext::cleaning_end();
- }
- 
- void ShenandoahUnload::purge() {
-   {
-     SuspendibleThreadSetJoiner sts;
-     ShenandoahCodeRoots::purge(ShenandoahHeap::heap()->workers());
-   }
- 
-   ClassLoaderDataGraph::purge();
-   CodeCache::purge_exception_caches();
- }
- 
  class ShenandoahUnloadRendezvousClosure : public HandshakeClosure {
  public:
    ShenandoahUnloadRendezvousClosure() : HandshakeClosure("ShenandoahUnloadRendezvous") {}
    void do_thread(Thread* thread) {}
  };
  
  void ShenandoahUnload::unload() {
    assert(ShenandoahConcurrentRoots::can_do_concurrent_class_unloading(), "Why we here?");
!   if (!ShenandoahHeap::heap()->is_concurrent_weak_root_in_progress()) {
      return;
    }
  
    // Unlink stale metadata and nmethods
!   unlink();
  
    // Make sure stale metadata and nmethods are no longer observable
!   ShenandoahUnloadRendezvousClosure cl;
!   Handshake::execute(&cl);
  
    // Purge stale metadata and nmethods that were unlinked
!   purge();
  }
  
  void ShenandoahUnload::finish() {
    MetaspaceGC::compute_new_size();
    MetaspaceUtils::verify_metrics();
--- 134,210 ----
    assert(ShenandoahConcurrentRoots::can_do_concurrent_class_unloading(), "Sanity");
    CodeCache::increment_unloading_cycle();
    DependencyContext::cleaning_start();
  }
  
  class ShenandoahUnloadRendezvousClosure : public HandshakeClosure {
  public:
    ShenandoahUnloadRendezvousClosure() : HandshakeClosure("ShenandoahUnloadRendezvous") {}
    void do_thread(Thread* thread) {}
  };
  
  void ShenandoahUnload::unload() {
    assert(ShenandoahConcurrentRoots::can_do_concurrent_class_unloading(), "Why we here?");
! 
!   ShenandoahHeap* heap = ShenandoahHeap::heap();
! 
!   if (!heap->is_concurrent_weak_root_in_progress()) {
      return;
    }
  
    // Unlink stale metadata and nmethods
!   {
!     ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_unlink);
! 
!     SuspendibleThreadSetJoiner sts;
!     bool unloadingOccurred;
!     {
!       ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_unlink_sd);
!       MutexLocker cldgMl(ClassLoaderDataGraph_lock);
!       unloadingOccurred = SystemDictionary::do_unloading(heap->gc_timer());
!     }
! 
!     {
!       ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_unlink_weak_klass);
!       Klass::clean_weak_klass_links(unloadingOccurred);
!     }
! 
!     {
!       ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_unlink_code_roots);
!       ShenandoahCodeRoots::unlink(heap->workers(), unloadingOccurred);
!     }
! 
!     DependencyContext::cleaning_end();
!   }
  
    // Make sure stale metadata and nmethods are no longer observable
!   {
!     ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_rendezvous);
!     ShenandoahUnloadRendezvousClosure cl;
!     Handshake::execute(&cl);
!   }
  
    // Purge stale metadata and nmethods that were unlinked
!   {
!     ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_purge);
! 
!     {
!       ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_purge_coderoots);
!       SuspendibleThreadSetJoiner sts;
!       ShenandoahCodeRoots::purge(heap->workers());
!     }
! 
!     {
!       ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_purge_cldg);
!       ClassLoaderDataGraph::purge();
!     }
! 
!     {
!       ShenandoahTimingsTracker t(ShenandoahPhaseTimings::conc_class_unload_purge_ec);
!       CodeCache::purge_exception_caches();
!     }
!   }
  }
  
  void ShenandoahUnload::finish() {
    MetaspaceGC::compute_new_size();
    MetaspaceUtils::verify_metrics();