--- old/src/hotspot/share/gc/z/zUnload.cpp	2019-11-11 21:19:23.602224584 +0100
+++ new/src/hotspot/share/gc/z/zUnload.cpp	2019-11-11 21:19:23.065206783 +0100
@@ -36,7 +36,8 @@
 #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:
@@ -126,6 +127,11 @@
 }
 
 void ZUnload::unlink() {
+  if (!ClassUnloading) {
+    return;
+  }
+
+  ZStatTimer timer(ZSubPhaseConcurrentClassesUnlink);
   SuspendibleThreadSetJoiner sts;
   bool unloading_occurred;
 
@@ -135,13 +141,17 @@
   }
 
   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);
@@ -151,29 +161,6 @@
   CodeCache::purge_exception_caches();
 }
 
-class ZUnloadRendezvousClosure : public ThreadClosure {
-public:
-  void do_thread(Thread* thread) {}
-};
-
-void ZUnload::unload() {
-  if (!ClassUnloading) {
-    return;
-  }
-
-  ZStatTimer timer(ZSubPhaseConcurrentClassesUnload);
-
-  // Unlink stale metadata and nmethods
-  unlink();
-
-  // Make sure stale metadata and nmethods are no longer observable
-  ZUnloadRendezvousClosure cl;
-  Handshake::execute(&cl);
-
-  // Purge stale metadata and nmethods that were unlinked
-  purge();
-}
-
 void ZUnload::finish() {
   // Resize and verify metaspace
   MetaspaceGC::compute_new_size();