--- old/src/share/vm/classfile/classLoaderData.cpp	2016-12-21 08:13:50.567595694 -0500
+++ new/src/share/vm/classfile/classLoaderData.cpp	2016-12-21 08:13:49.512884288 -0500
@@ -205,12 +205,13 @@
 }
 
 void ClassLoaderData::modules_do(void f(ModuleEntry*)) {
-  assert_locked_or_safepoint(Module_lock);
-  if (_modules != NULL) {
-    for (int i = 0; i < _modules->table_size(); i++) {
-      for (ModuleEntry* entry = _modules->bucket(i);
-                              entry != NULL;
-                              entry = entry->next()) {
+  // Lock-free access requires load_ptr_acquire
+  ModuleEntryTable* modules = load_ptr_acquire(&_modules);
+  if (modules != NULL) {
+    for (int i = 0; i < modules->table_size(); i++) {
+      for (ModuleEntry* entry = modules->bucket(i);
+           entry != NULL;
+           entry = entry->next()) {
         f(entry);
       }
     }
@@ -223,8 +224,8 @@
   if (packages != NULL) {
     for (int i = 0; i < packages->table_size(); i++) {
       for (PackageEntry* entry = packages->bucket(i);
-                              entry != NULL;
-                              entry = entry->next()) {
+           entry != NULL;
+           entry = entry->next()) {
         f(entry);
       }
     }
--- old/src/share/vm/classfile/moduleEntry.cpp	2016-12-21 08:13:53.924498638 -0500
+++ new/src/share/vm/classfile/moduleEntry.cpp	2016-12-21 08:13:52.882463414 -0500
@@ -167,7 +167,6 @@
 }
 
 bool ModuleEntry::has_reads() const {
-  assert_locked_or_safepoint(Module_lock);
   return ((_reads != NULL) && !_reads->is_empty());
 }
 
@@ -202,9 +201,7 @@
 }
 
 void ModuleEntry::module_reads_do(ModuleClosure* const f) {
-  assert_locked_or_safepoint(Module_lock);
   assert(f != NULL, "invariant");
-
   if (has_reads()) {
     int reads_len = _reads->length();
     for (int i = 0; i < reads_len; ++i) {
@@ -225,7 +222,7 @@
 }
 
 ModuleEntryTable::~ModuleEntryTable() {
-  assert_locked_or_safepoint(Module_lock);
+  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 
   // Walk through all buckets and all entries in each bucket,
   // freeing each entry.
--- old/src/share/vm/classfile/packageEntry.cpp	2016-12-21 08:13:57.283947713 -0500
+++ new/src/share/vm/classfile/packageEntry.cpp	2016-12-21 08:13:56.229596439 -0500
@@ -98,17 +98,9 @@
   }
 
   if (m == NULL) {
-    // NULL indicates the package is being unqualifiedly exported
-    if (has_qual_exports_list()) {
-      // Legit to transition a package from being qualifiedly exported
-      // to unqualified.  Clean up the qualified lists at the next
-      // safepoint.
-      _exported_pending_delete = _qualified_exports;
-    }
-
-    // Mark package as unqualifiedly exported
+    // NULL indicates the package is being unqualifiedly exported.  Clean up
+    // the qualified list at the next safepoint.
     set_unqual_exported();
-
   } else {
     // Add the exported module
     add_qexport(m);
@@ -160,18 +152,9 @@
 
 void PackageEntry::delete_qualified_exports() {
   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
-  if (_exported_pending_delete != NULL) {
-    // If a transition occurred from qualified to unqualified, the _qualified_exports
-    // field should have been NULL'ed out.
-    assert(_qualified_exports == NULL, "Package's exported pending delete, exported list should not be active");
-    delete _exported_pending_delete;
-  }
-
   if (_qualified_exports != NULL) {
     delete _qualified_exports;
   }
-
-  _exported_pending_delete = NULL;
   _qualified_exports = NULL;
 }
 
@@ -181,7 +164,7 @@
 }
 
 PackageEntryTable::~PackageEntryTable() {
-  assert_locked_or_safepoint(Module_lock);
+  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 
   // Walk through all buckets and all entries in each bucket,
   // freeing each entry.
@@ -302,12 +285,9 @@
 
 // iteration of qualified exports
 void PackageEntry::package_exports_do(ModuleClosure* const f) {
-  assert_locked_or_safepoint(Module_lock);
   assert(f != NULL, "invariant");
-
   if (has_qual_exports_list()) {
     int qe_len = _qualified_exports->length();
-
     for (int i = 0; i < qe_len; ++i) {
       f->do_module(_qualified_exports->at(i));
     }
--- old/src/share/vm/classfile/packageEntry.hpp	2016-12-21 08:14:00.565631527 -0500
+++ new/src/share/vm/classfile/packageEntry.hpp	2016-12-21 08:13:59.522757025 -0500
@@ -70,7 +70,6 @@
   bool _is_exported_unqualified;
   bool _is_exported_allUnnamed;
   bool _must_walk_exports;
-  GrowableArray<ModuleEntry*>* _exported_pending_delete; // transitioned from qualified to unqualified, delete at safepoint
   GrowableArray<ModuleEntry*>* _qualified_exports;
   TRACE_DEFINE_TRACE_ID_FIELD;
 
@@ -84,7 +83,6 @@
     _is_exported_unqualified = false;
     _is_exported_allUnnamed = false;
     _must_walk_exports = false;
-    _exported_pending_delete = NULL;
     _qualified_exports = NULL;
   }
 
@@ -106,29 +104,20 @@
   }
   // Returns true if there are any explicit qualified exports
   bool has_qual_exports_list() const {
-    assert(!(_qualified_exports != NULL && _is_exported_unqualified),
-           "_qualified_exports set at same time as _is_exported_unqualified");
-    return (_qualified_exports != NULL);
+    return (!is_unqual_exported() && _qualified_exports != NULL);
   }
   bool is_exported_allUnnamed() const {
-    assert(!(_is_exported_allUnnamed && _is_exported_unqualified),
-           "_is_exported_allUnnamed set at same time as _is_exported_unqualified");
-    return _is_exported_allUnnamed;
+    return (!is_unqual_exported() && _is_exported_allUnnamed);
   }
   bool is_unqual_exported() const {
-    assert(!(_qualified_exports != NULL && _is_exported_unqualified),
-           "_qualified_exports set at same time as _is_exported_unqualified");
-    assert(!(_is_exported_allUnnamed && _is_exported_unqualified),
-           "_is_exported_allUnnamed set at same time as _is_exported_unqualified");
     return _is_exported_unqualified;
   }
   void set_unqual_exported() {
     assert(Module_lock->owned_by_self(), "should have the Module_lock");
     _is_exported_unqualified = true;
     _is_exported_allUnnamed = false;
-    _qualified_exports = NULL;
   }
-  bool exported_pending_delete() const     { return (_exported_pending_delete != NULL); }
+  bool exported_pending_delete() const { return (is_unqual_exported() && _qualified_exports != NULL); }
 
   void set_exported(ModuleEntry* m);