src/hotspot/share/gc/z/zUnload.cpp

@@ -34,11 +34,12 @@
 #include "gc/z/zOopClosures.hpp"
 #include "gc/z/zStat.hpp"
 #include "gc/z/zUnload.hpp"
 #include "oops/access.inline.hpp"
 
-static const ZStatSubPhase ZSubPhaseConcurrentClassesUnload("Concurrent Classes Unload");
+static const ZStatSubPhase ZSubPhaseConcurrentClassesUnlink("Concurrent Classes Unlink");
+static const ZStatSubPhase ZSubPhaseConcurrentClassesPurge("Concurrent Classes Purge");
 
 class ZIsUnloadingOopClosure : public OopClosure {
 private:
   ZPhantomIsAliveObjectClosure _is_alive;
   bool                         _is_unloading;

@@ -124,61 +125,44 @@
   CodeCache::increment_unloading_cycle();
   DependencyContext::cleaning_start();
 }
 
 void ZUnload::unlink() {
+  if (!ClassUnloading) {
+    return;
+  }
+
+  ZStatTimer timer(ZSubPhaseConcurrentClassesUnlink);
   SuspendibleThreadSetJoiner sts;
   bool unloading_occurred;
 
   {
     MutexLocker ml(ClassLoaderDataGraph_lock);
     unloading_occurred = SystemDictionary::do_unloading(ZStatPhase::timer());
   }
 
   Klass::clean_weak_klass_links(unloading_occurred);
-
   ZNMethod::unlink(_workers, unloading_occurred);
-
   DependencyContext::cleaning_end();
 }
 
 void ZUnload::purge() {
+  if (!ClassUnloading) {
+    return;
+  }
+
+  ZStatTimer timer(ZSubPhaseConcurrentClassesPurge);
+
   {
     SuspendibleThreadSetJoiner sts;
     ZNMethod::purge(_workers);
   }
 
   ClassLoaderDataGraph::purge();
   CodeCache::purge_exception_caches();
 }
 
-class ZUnloadRendezvousClosure : public ThreadClosure {
-public:
-  void do_thread(Thread* thread) {}
-};
-
-void ZUnload::unload() {
-  ZUnloadRendezvousClosure cl;
-  if (!ClassUnloading) {
-    // Even when we don't use class unloading, we want a handshake to
-    // close the resurrection block window.
-    Handshake::execute(&cl);
-    return;
-  }
-
-  ZStatTimer timer(ZSubPhaseConcurrentClassesUnload);
-
-  // Unlink stale metadata and nmethods
-  unlink();
-
-  // Make sure stale metadata and nmethods are no longer observable
-  Handshake::execute(&cl);
-
-  // Purge stale metadata and nmethods that were unlinked
-  purge();
-}
-
 void ZUnload::finish() {
   // Resize and verify metaspace
   MetaspaceGC::compute_new_size();
   MetaspaceUtils::verify_metrics();
 }