--- old/src/hotspot/share/classfile/classLoaderData.cpp	2018-08-23 18:48:18.121025125 -0400
+++ new/src/hotspot/share/classfile/classLoaderData.cpp	2018-08-23 18:48:17.684725156 -0400
@@ -76,11 +76,6 @@
 #include "utilities/growableArray.hpp"
 #include "utilities/macros.hpp"
 #include "utilities/ostream.hpp"
-#include "utilities/ticks.hpp"
-#if INCLUDE_JFR
-#include "jfr/jfr.hpp"
-#include "jfr/jfrEvents.hpp"
-#endif
 
 volatile size_t ClassLoaderDataGraph::_num_array_classes = 0;
 volatile size_t ClassLoaderDataGraph::_num_instance_classes = 0;
@@ -1325,29 +1320,6 @@
 }
 #endif // PRODUCT
 
-#if INCLUDE_JFR
-static Ticks class_unload_time;
-static void post_class_unload_event(Klass* const k) {
-  assert(k != NULL, "invariant");
-  EventClassUnload event(UNTIMED);
-  event.set_endtime(class_unload_time);
-  event.set_unloadedClass(k);
-  event.set_definingClassLoader(k->class_loader_data());
-  event.commit();
-}
-
-static void post_class_unload_events() {
-  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
-  if (Jfr::is_enabled()) {
-    if (EventClassUnload::is_enabled()) {
-      class_unload_time = Ticks::now();
-      ClassLoaderDataGraph::classes_unloading_do(&post_class_unload_event);
-    }
-    Jfr::on_unloading_classes();
-  }
-}
-#endif // INCLUDE_JFR
-
 // Move class loader data from main list to the unloaded list for unloading
 // and deallocation later.
 bool ClassLoaderDataGraph::do_unloading(bool do_cleaning) {
@@ -1391,10 +1363,6 @@
     _unloading = dead;
   }
 
-  if (seen_dead_loader) {
-    JFR_ONLY(post_class_unload_events();)
-  }
-
   log_debug(class, loader, data)("do_unloading: loaders processed %u, loaders removed %u", loaders_processed, loaders_removed);
 
   return seen_dead_loader;
--- old/src/hotspot/share/classfile/systemDictionary.cpp	2018-08-23 18:48:19.532188787 -0400
+++ new/src/hotspot/share/classfile/systemDictionary.cpp	2018-08-23 18:48:19.101707767 -0400
@@ -47,6 +47,7 @@
 #include "gc/shared/oopStorage.inline.hpp"
 #include "interpreter/bytecodeStream.hpp"
 #include "interpreter/interpreter.hpp"
+#include "jfr/jfr.hpp"
 #include "jfr/jfrEvents.hpp"
 #include "logging/log.hpp"
 #include "logging/logStream.hpp"
@@ -83,6 +84,7 @@
 #include "services/diagnosticCommand.hpp"
 #include "services/threadService.hpp"
 #include "utilities/macros.hpp"
+#include "utilities/ticks.hpp"
 #if INCLUDE_CDS
 #include "classfile/systemDictionaryShared.hpp"
 #endif
@@ -1851,10 +1853,22 @@
   {
     GCTraceTime(Debug, gc, phases) t("ClassLoaderData", gc_timer);
 
+#if INCLUDE_JFR
+    // If unloading occurs, make sure time stamp is consistent.
+    if (Jfr::is_enabled()) {
+      InstanceKlass::set_class_unload_time(Ticks::now());
+    }
+#endif
+
     // First, mark for unload all ClassLoaderData referencing a dead class loader.
     unloading_occurred = ClassLoaderDataGraph::do_unloading(do_cleaning);
     if (unloading_occurred) {
       ClassLoaderDataGraph::clean_module_and_package_info();
+#if INCLUDE_JFR
+      if (Jfr::is_enabled()) {
+        Jfr::on_unloading_classes();
+      }
+#endif
     }
   }
 
--- old/src/hotspot/share/oops/instanceKlass.cpp	2018-08-23 18:48:20.979965069 -0400
+++ new/src/hotspot/share/oops/instanceKlass.cpp	2018-08-23 18:48:20.549286093 -0400
@@ -80,6 +80,13 @@
 #ifdef COMPILER1
 #include "c1/c1_Compiler.hpp"
 #endif
+#if INCLUDE_JFR
+#include "utilities/ticks.hpp"
+#include "jfr/jfr.hpp"
+#include "jfr/jfrEvents.hpp"
+Ticks InstanceKlass::_class_unload_time;
+#endif
+
 
 #ifdef DTRACE_ENABLED
 
@@ -2423,6 +2430,18 @@
 
   // notify ClassLoadingService of class unload
   ClassLoadingService::notify_class_unloaded(ik);
+
+#if INCLUDE_JFR
+  if (Jfr::is_enabled()) {
+    assert(ik != NULL, "invariant");
+    EventClassUnload event(UNTIMED);
+    event.set_endtime(class_unload_time());
+    event.set_unloadedClass(ik);
+    event.set_definingClassLoader(ik->class_loader_data());
+    event.commit();
+  }
+#endif
+
 }
 
 void InstanceKlass::release_C_heap_structures(InstanceKlass* ik) {
--- old/src/hotspot/share/oops/instanceKlass.hpp	2018-08-23 18:48:22.447358608 -0400
+++ new/src/hotspot/share/oops/instanceKlass.hpp	2018-08-23 18:48:22.018898651 -0400
@@ -41,6 +41,7 @@
 #include "utilities/align.hpp"
 #include "utilities/macros.hpp"
 #if INCLUDE_JFR
+#include "utilities/ticks.hpp"
 #include "jfr/support/jfrKlassExtension.hpp"
 #endif
 
@@ -142,6 +143,11 @@
  private:
   static InstanceKlass* allocate_instance_klass(const ClassFileParser& parser, TRAPS);
 
+#if INCLUDE_JFR
+  // JFR Class unloading timestamp
+  static Ticks _class_unload_time;
+#endif
+
  protected:
   // If you add a new field that points to any metaspace object, you
   // must add this field to InstanceKlass::metaspace_pointers_do().
@@ -426,6 +432,11 @@
     _transitive_interfaces = a;
   }
 
+#if INCLUDE_JFR
+  static void set_class_unload_time(Ticks ticks) { _class_unload_time = ticks; }
+  static Ticks class_unload_time() { return _class_unload_time; }
+#endif
+
  private:
   friend class fieldDescriptor;
   FieldInfo* field(int index) const { return FieldInfo::from_field_array(_fields, index); }