8027146: Class loading verification failure if GC occurs in Universe::flush_dependents_on

Summary: Remove search in system dictionary and hacks, replace with verifying in CLD::_klasses list.
Reviewed-by: dcubed, acorn

hotspot/src/share/vm/classfile/classLoaderData.cpp

 /*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -520,6 +520,13 @@ void ClassLoaderData::verify() {
   }
 }
 
+bool ClassLoaderData::contains_klass(Klass* klass) {
+  for (Klass* k = _klasses; k != NULL; k = k->next_link()) {
+    if (k == klass) return true;
+  }
+  return false;
+}
+
 
 // GC root of class loader data created.
 ClassLoaderData* ClassLoaderDataGraph::_head = NULL;

hotspot/src/share/vm/classfile/classLoaderData.hpp

 /*
- * Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -260,6 +260,7 @@ class ClassLoaderData : public CHeapObj<mtClass> {
   jobject add_handle(Handle h);
   void add_class(Klass* k);
   void remove_class(Klass* k);
+  bool contains_klass(Klass* k);
   void record_dependency(Klass* to, TRAPS);
   void init_dependencies(TRAPS);
 

hotspot/src/share/vm/classfile/dictionary.cpp

 /*
- * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -707,7 +707,7 @@ void Dictionary::verify() {
                 loader_data->class_loader() == NULL ||
                 loader_data->class_loader()->is_instance(),
                 "checking type of class_loader");
-      e->verify(/*check_dictionary*/false);
+      e->verify();
       probe->verify_protection_domain_set();
       element_count++;
     }

hotspot/src/share/vm/classfile/systemDictionary.cpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -2650,23 +2650,6 @@ void SystemDictionary::verify() {
   constraints()->verify(dictionary(), placeholders());
 }
 
-
-void SystemDictionary::verify_obj_klass_present(Symbol* class_name,
-                                                ClassLoaderData* loader_data) {
-  GCMutexLocker mu(SystemDictionary_lock);
-  Symbol* name;
-
-  Klass* probe = find_class(class_name, loader_data);
-  if (probe == NULL) {
-    probe = SystemDictionary::find_shared_class(class_name);
-    if (probe == NULL) {
-      name = find_placeholder(class_name, loader_data);
-    }
-  }
-  guarantee(probe != NULL || name != NULL,
-            "Loaded klasses should be in SystemDictionary");
-}
-
 // utility function for class load event
 void SystemDictionary::post_class_load_event(const Ticks& start_time,
                                              instanceKlassHandle k,

hotspot/src/share/vm/classfile/systemDictionary.hpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -375,10 +375,6 @@ public:
   static bool is_internal_format(Symbol* class_name);
 #endif
 
-  // Verify class is in dictionary
-  static void verify_obj_klass_present(Symbol* class_name,
-                                       ClassLoaderData* loader_data);
-
   // Initialization
   static void initialize(TRAPS);
 

hotspot/src/share/vm/oops/arrayKlass.cpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -214,8 +214,8 @@ void ArrayKlass::oop_print_on(oop obj, outputStream* st) {
 
 // Verification
 
-void ArrayKlass::verify_on(outputStream* st, bool check_dictionary) {
-  Klass::verify_on(st, check_dictionary);
+void ArrayKlass::verify_on(outputStream* st) {
+  Klass::verify_on(st);
 
   if (component_mirror() != NULL) {
     guarantee(component_mirror()->klass() != NULL, "should have a class");

hotspot/src/share/vm/oops/arrayKlass.hpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -146,7 +146,7 @@ class ArrayKlass: public Klass {
   void oop_print_on(oop obj, outputStream* st);
 
   // Verification
-  void verify_on(outputStream* st, bool check_dictionary);
+  void verify_on(outputStream* st);
 
   void oop_verify_on(oop obj, outputStream* st);
 };

hotspot/src/share/vm/oops/instanceKlass.cpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -3180,7 +3180,7 @@ class VerifyFieldClosure: public OopClosure {
   virtual void do_oop(narrowOop* p) { VerifyFieldClosure::do_oop_work(p); }
 };
 
-void InstanceKlass::verify_on(outputStream* st, bool check_dictionary) {
+void InstanceKlass::verify_on(outputStream* st) {
 #ifndef PRODUCT
   // Avoid redundant verifies, this really should be in product.
   if (_verify_count == Universe::verify_count()) return;
@@ -3188,14 +3188,11 @@ void InstanceKlass::verify_on(outputStream* st, bool check_dictionary) {
 #endif
 
   // Verify Klass
-  Klass::verify_on(st, check_dictionary);
+  Klass::verify_on(st);
 
-  // Verify that klass is present in SystemDictionary if not already
-  // verifying the SystemDictionary.
-  if (is_loaded() && !is_anonymous() && check_dictionary) {
-    Symbol* h_name = name();
-    SystemDictionary::verify_obj_klass_present(h_name, class_loader_data());
-  }
+  // Verify that klass is present in ClassLoaderData
+  guarantee(class_loader_data()->contains_klass(this),
+            "this class isn't found in class loader data");
 
   // Verify vtables
   if (is_linked()) {

hotspot/src/share/vm/oops/instanceKlass.hpp

@@ -1087,7 +1087,7 @@ public:
   const char* internal_name() const;
 
   // Verification
-  void verify_on(outputStream* st, bool check_dictionary);
+  void verify_on(outputStream* st);
 
   void oop_verify_on(oop obj, outputStream* st);
 };

hotspot/src/share/vm/oops/klass.cpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -638,7 +638,7 @@ void Klass::collect_statistics(KlassSizeStats *sz) const {
 
 // Verification
 
-void Klass::verify_on(outputStream* st, bool check_dictionary) {
+void Klass::verify_on(outputStream* st) {
 
   // This can be expensive, but it is worth checking that this klass is actually
   // in the CLD graph but not in production.

hotspot/src/share/vm/oops/klass.hpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -695,8 +695,8 @@ class Klass : public Metadata {
   virtual const char* internal_name() const = 0;
 
   // Verification
-  virtual void verify_on(outputStream* st, bool check_dictionary);
-  void verify(bool check_dictionary = true) { verify_on(tty, check_dictionary); }
+  virtual void verify_on(outputStream* st);
+  void verify() { verify_on(tty); }
 
 #ifndef PRODUCT
   bool verify_vtable_index(int index);

hotspot/src/share/vm/oops/objArrayKlass.cpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -674,8 +674,8 @@ const char* ObjArrayKlass::internal_name() const {
 
 // Verification
 
-void ObjArrayKlass::verify_on(outputStream* st, bool check_dictionary) {
-  ArrayKlass::verify_on(st, check_dictionary);
+void ObjArrayKlass::verify_on(outputStream* st) {
+  ArrayKlass::verify_on(st);
   guarantee(element_klass()->is_klass(), "should be klass");
   guarantee(bottom_klass()->is_klass(), "should be klass");
   Klass* bk = bottom_klass();

hotspot/src/share/vm/oops/objArrayKlass.hpp

 /*
- * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -151,7 +151,7 @@ class ObjArrayKlass : public ArrayKlass {
   const char* internal_name() const;
 
   // Verification
-  void verify_on(outputStream* st, bool check_dictionary);
+  void verify_on(outputStream* st);
 
   void oop_verify_on(oop obj, outputStream* st);
 };