--- a/agent/src/share/classes/sun/jvm/hotspot/gc_implementation/g1/G1HeapRegionTable.java	Tue Dec 03 13:56:10 2013 -0800
+++ b/agent/src/share/classes/sun/jvm/hotspot/gc_implementation/g1/G1HeapRegionTable.java	Thu Dec 05 17:49:55 2013 +0100
@@ -103,14 +103,14 @@
         @Override
         public void remove()     { /* not supported */    }
 
-        HeapRegionIterator(Address addr) {
+        HeapRegionIterator(long committedLength) {
             index = 0;
-            length = length();
+            length = committedLength;
         }
     }
 
-    public Iterator<HeapRegion> heapRegionIterator() {
-        return new HeapRegionIterator(addr);
+    public Iterator<HeapRegion> heapRegionIterator(long committedLength) {
+        return new HeapRegionIterator(committedLength);
     }
 
     public G1HeapRegionTable(Address addr) {

--- a/agent/src/share/classes/sun/jvm/hotspot/gc_implementation/g1/HeapRegionSeq.java	Tue Dec 03 13:56:10 2013 -0800
+++ b/agent/src/share/classes/sun/jvm/hotspot/gc_implementation/g1/HeapRegionSeq.java	Thu Dec 05 17:49:55 2013 +0100
@@ -42,6 +42,8 @@
 public class HeapRegionSeq extends VMObject {
     // G1HeapRegionTable _regions
     static private long regionsFieldOffset;
+    // uint _committed_length
+    static private CIntegerField committedLengthField;
 
     static {
         VM.registerVMInitializedObserver(new Observer() {
@@ -55,6 +57,7 @@
         Type type = db.lookupType("HeapRegionSeq");
 
         regionsFieldOffset = type.getField("_regions").getOffset();
+        committedLengthField = type.getCIntegerField("_committed_length");
     }
 
     private G1HeapRegionTable regions() {
@@ -67,8 +70,12 @@
         return regions().length();
     }
 
+    public long committedLength() {
+        return committedLengthField.getValue(addr);
+    }
+
     public Iterator<HeapRegion> heapRegionIterator() {
-        return regions().heapRegionIterator();
+        return regions().heapRegionIterator(committedLength());
     }
 
     public HeapRegionSeq(Address addr) {

--- a/src/share/vm/gc_implementation/shared/markSweep.cpp	Tue Dec 03 13:56:10 2013 -0800
+++ b/src/share/vm/gc_implementation/shared/markSweep.cpp	Thu Dec 05 17:49:55 2013 +0100
@@ -66,29 +66,10 @@
   klass->oops_do(&MarkSweep::adjust_pointer_closure);
 }
 
-void MarkSweep::follow_klass(Klass* klass) {
-  ClassLoaderData* cld = klass->class_loader_data();
-  // The actual processing of the klass is done when we
-  // traverse the list of Klasses in the class loader data.
-  MarkSweep::follow_class_loader(cld);
-}
-
-void MarkSweep::adjust_klass(Klass* klass) {
-  ClassLoaderData* cld = klass->class_loader_data();
-  // The actual processing of the klass is done when we
-  // traverse the list of Klasses in the class loader data.
-  MarkSweep::adjust_class_loader(cld);
-}
-
 void MarkSweep::follow_class_loader(ClassLoaderData* cld) {
   cld->oops_do(&MarkSweep::mark_and_push_closure, &MarkSweep::follow_klass_closure, true);
 }
 
-void MarkSweep::adjust_class_loader(ClassLoaderData* cld) {
-  cld->oops_do(&MarkSweep::adjust_pointer_closure, &MarkSweep::adjust_klass_closure, true);
-}
-
-
 void MarkSweep::follow_stack() {
   do {
     while (!_marking_stack.is_empty()) {

--- a/src/share/vm/gc_implementation/shared/markSweep.hpp	Tue Dec 03 13:56:10 2013 -0800
+++ b/src/share/vm/gc_implementation/shared/markSweep.hpp	Thu Dec 05 17:49:55 2013 +0100
@@ -172,10 +172,8 @@
   static void follow_stack();   // Empty marking stack.
 
   static void follow_klass(Klass* klass);
-  static void adjust_klass(Klass* klass);
 
   static void follow_class_loader(ClassLoaderData* cld);
-  static void adjust_class_loader(ClassLoaderData* cld);
 
   static void preserve_mark(oop p, markOop mark);
                                 // Save the mark word so it can be restored later

--- a/src/share/vm/gc_implementation/shared/markSweep.inline.hpp	Tue Dec 03 13:56:10 2013 -0800
+++ b/src/share/vm/gc_implementation/shared/markSweep.inline.hpp	Thu Dec 05 17:49:55 2013 +0100
@@ -44,6 +44,11 @@
   }
 }
 
+inline void MarkSweep::follow_klass(Klass* klass) {
+  oop op = klass->klass_holder();
+  MarkSweep::mark_and_push(&op);
+}
+
 template <class T> inline void MarkSweep::follow_root(T* p) {
   assert(!Universe::heap()->is_in_reserved(p),
          "roots shouldn't be things within the heap");

--- a/src/share/vm/oops/instanceKlass.cpp	Tue Dec 03 13:56:10 2013 -0800
+++ b/src/share/vm/oops/instanceKlass.cpp	Thu Dec 05 17:49:55 2013 +0100
@@ -2180,7 +2180,6 @@
     obj, \
     MarkSweep::adjust_pointer(p), \
     assert_is_in)
-  MarkSweep::adjust_klass(obj->klass());
   return size;
 }
 

--- a/src/share/vm/oops/instanceMirrorKlass.cpp	Tue Dec 03 13:56:10 2013 -0800
+++ b/src/share/vm/oops/instanceMirrorKlass.cpp	Thu Dec 05 17:49:55 2013 +0100
@@ -155,7 +155,13 @@
   // Follow the klass field in the mirror.
   Klass* klass = java_lang_Class::as_Klass(obj);
   if (klass != NULL) {
-    MarkSweep::follow_klass(klass);
+    // For anonymous classes we need to handle the class loader data,
+    // otherwise it won't be claimed and can be unloaded.
+    if (klass->oop_is_instance() && InstanceKlass::cast(klass)->is_anonymous()) {
+      MarkSweep::follow_class_loader(klass->class_loader_data());
+    } else {
+      MarkSweep::follow_klass(klass);
+    }
   } else {
     // If klass is NULL then this a mirror for a primitive type.
     // We don't have to follow them, since they are handled as strong
@@ -196,17 +202,6 @@
   int size = oop_size(obj);
   InstanceKlass::oop_adjust_pointers(obj);
 
-  // Follow the klass field in the mirror.
-  Klass* klass = java_lang_Class::as_Klass(obj);
-  if (klass != NULL) {
-    MarkSweep::adjust_klass(klass);
-  } else {
-    // If klass is NULL then this a mirror for a primitive type.
-    // We don't have to follow them, since they are handled as strong
-    // roots in Universe::oops_do.
-    assert(java_lang_Class::is_primitive(obj), "Sanity check");
-  }
-
   InstanceMirrorKlass_OOP_ITERATE(                                                    \
     start_of_static_fields(obj), java_lang_Class::static_oop_field_count(obj),        \
     MarkSweep::adjust_pointer(p),                                                     \

--- a/src/share/vm/oops/objArrayKlass.cpp	Tue Dec 03 13:56:10 2013 -0800
+++ b/src/share/vm/oops/objArrayKlass.cpp	Thu Dec 05 17:49:55 2013 +0100
@@ -569,7 +569,6 @@
   // Get size before changing pointers.
   // Don't call size() or oop_size() since that is a virtual call.
   int size = a->object_size();
-  MarkSweep::adjust_klass(a->klass());
   ObjArrayKlass_OOP_ITERATE(a, p, MarkSweep::adjust_pointer(p))
   return size;
 }