8264644: Add PrintClassLoaderDataGraphAtExit to print the detailed CLD graph

Reviewed-by: coleenp, dholmes, shade

src/hotspot/share/classfile/classLoaderData.cpp

@@ -930,20 +930,57 @@ void ClassLoaderData::print_value_on(outputStream* out) const {
 void ClassLoaderData::print_value() const { print_value_on(tty); }
 
 #ifndef PRODUCT
-void ClassLoaderData::print_on(outputStream* out) const {
-  out->print("ClassLoaderData CLD: " PTR_FORMAT ", loader: " PTR_FORMAT ", loader_klass: %s {",
-              p2i(this), p2i(_class_loader.ptr_raw()), loader_name_and_id());
-  if (has_class_mirror_holder()) out->print(" has a class holder");
-  if (claimed()) out->print(" claimed");
-  if (is_unloading()) out->print(" unloading");
-  out->print(" metaspace: " INTPTR_FORMAT, p2i(metaspace_or_null()));
+class PrintKlassClosure: public KlassClosure {
+  outputStream* _out;
+public:
+  PrintKlassClosure(outputStream* out): _out(out) { }
 
-  if (_jmethod_ids != NULL) {
-    Method::print_jmethod_ids(this, out);
+  void do_klass(Klass* k) {
+    ResourceMark rm;
+    _out->print("%s,", k->external_name());
   }
-  out->print(" handles count %d", _handles.count());
-  out->print(" dependencies %d", _dependency_count);
-  out->print_cr("}");
+};
+
+void ClassLoaderData::print_on(outputStream* out) const {
+  ResourceMark rm;
+  out->print_cr("ClassLoaderData(" INTPTR_FORMAT ")", p2i(this));
+  out->print_cr(" - name                %s", loader_name_and_id());
+  if (!_holder.is_null()) {
+    out->print   (" - holder              ");
+    _holder.print_on(out);
+    out->print_cr("");
+  }
+  out->print_cr(" - class loader        " INTPTR_FORMAT, p2i(_class_loader.ptr_raw()));
+  out->print_cr(" - metaspace           " INTPTR_FORMAT, p2i(_metaspace));
+  out->print_cr(" - unloading           %s", _unloading ? "true" : "false");
+  out->print_cr(" - class mirror holder %s", _has_class_mirror_holder ? "true" : "false");
+  out->print_cr(" - modified oops       %s", _modified_oops ? "true" : "false");
+  out->print_cr(" - keep alive          %d", _keep_alive);
+  out->print   (" - claim               ");
+  switch(_claim) {
+    case _claim_none:       out->print_cr("none"); break;
+    case _claim_finalizable:out->print_cr("finalizable"); break;
+    case _claim_strong:     out->print_cr("strong"); break;
+    case _claim_other:      out->print_cr("other"); break;
+    default:                ShouldNotReachHere();
+  }
+  out->print_cr(" - handles             %d", _handles.count());
+  out->print_cr(" - dependency count    %d", _dependency_count);
+  out->print   (" - klasses             {");
+  PrintKlassClosure closure(out);
+  ((ClassLoaderData*)this)->classes_do(&closure);
+  out->print_cr(" }");
+  out->print_cr(" - packages            " INTPTR_FORMAT, p2i(_packages));
+  out->print_cr(" - module              " INTPTR_FORMAT, p2i(_modules));
+  out->print_cr(" - unnamed module      " INTPTR_FORMAT, p2i(_unnamed_module));
+  out->print_cr(" - dictionary          " INTPTR_FORMAT, p2i(_dictionary));
+  if (_jmethod_ids != NULL) {
+    out->print   (" - jmethod count       ");
+    Method::print_jmethod_ids_count(this, out);
+    out->print_cr("");
+  }
+  out->print_cr(" - deallocate list     " INTPTR_FORMAT, p2i(_deallocate_list));
+  out->print_cr(" - next CLD            " INTPTR_FORMAT, p2i(_next));
 }
 #endif // PRODUCT
 

src/hotspot/share/classfile/classLoaderDataGraph.cpp

@@ -673,6 +673,7 @@ void ClassLoaderDataGraph::verify() {
 // callable from debugger
 extern "C" int print_loader_data_graph() {
   ResourceMark rm;
+  MutexLocker ml(ClassLoaderDataGraph_lock);
   ClassLoaderDataGraph::print_on(tty);
   return 0;
 }

src/hotspot/share/oops/method.cpp

@@ -2255,8 +2255,8 @@ bool Method::is_valid_method(const Method* m) {
 }
 
 #ifndef PRODUCT
-void Method::print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) {
-  out->print(" jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
+void Method::print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) {
+  out->print("%d", loader_data->jmethod_ids()->count_methods());
 }
 #endif // PRODUCT
 

src/hotspot/share/oops/method.hpp

@@ -822,7 +822,7 @@ public:
 
   // Clear methods
   static void clear_jmethod_ids(ClassLoaderData* loader_data);
-  static void print_jmethod_ids(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
+  static void print_jmethod_ids_count(const ClassLoaderData* loader_data, outputStream* out) PRODUCT_RETURN;
 
   // Get this method's jmethodID -- allocate if it doesn't exist
   jmethodID jmethod_id();

src/hotspot/share/runtime/globals.hpp

@@ -686,6 +686,9 @@ const intx ObjectAlignmentInBytes = 8;
   notproduct(bool, PrintSystemDictionaryAtExit, false,                      \
           "Print the system dictionary at exit")                            \
                                                                             \
+  notproduct(bool, PrintClassLoaderDataGraphAtExit, false,                  \
+          "Print the class loader data graph at exit")                      \
+                                                                            \
   product(bool, DynamicallyResizeSystemDictionaries, true, DIAGNOSTIC,      \
           "Dynamically resize system dictionaries as needed")               \
                                                                             \

src/hotspot/share/runtime/java.cpp

@@ -325,6 +325,11 @@ void print_statistics() {
     ResourceMark rm;
     MutexLocker mcld(ClassLoaderDataGraph_lock);
     SystemDictionary::print();
+  }
+
+  if (PrintClassLoaderDataGraphAtExit) {
+    ResourceMark rm;
+    MutexLocker mcld(ClassLoaderDataGraph_lock);
     ClassLoaderDataGraph::print();
   }