8203219: VM.metaspace jcmd should optionally show loaded classes for loaders

Reviewed-by: zgu, coleenp

src/hotspot/share/memory/metaspace.cpp

@@ -601,11 +601,12 @@ void MetaspaceUtils::print_basic_report(outputStream* out, size_t scale) {
 void MetaspaceUtils::print_report(outputStream* out, size_t scale, int flags) {
 
   const bool print_loaders = (flags & rf_show_loaders) > 0;
+  const bool print_classes = (flags & rf_show_classes) > 0;
   const bool print_by_chunktype = (flags & rf_break_down_by_chunktype) > 0;
   const bool print_by_spacetype = (flags & rf_break_down_by_spacetype) > 0;
 
   // Some report options require walking the class loader data graph.
-  PrintCLDMetaspaceInfoClosure cl(out, scale, print_loaders, print_by_chunktype);
+  PrintCLDMetaspaceInfoClosure cl(out, scale, print_loaders, print_classes, print_by_chunktype);
   if (print_loaders) {
     out->cr();
     out->print_cr("Usage per loader:");

src/hotspot/share/memory/metaspace.hpp

@@ -389,7 +389,9 @@ public:
     // Print details about the underlying virtual spaces.
     rf_show_vslist                  = (1 << 3),
     // Print metaspace map.
-    rf_show_vsmap                   = (1 << 4)
+    rf_show_vsmap                   = (1 << 4),
+    // If show_loaders: show loaded classes for each loader.
+    rf_show_classes                 = (1 << 5)
   };
 
   // This will print out a basic metaspace usage report but

src/hotspot/share/memory/metaspace/metaspaceDCmd.cpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, SAP and/or its affiliates.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -34,6 +35,7 @@ MetaspaceDCmd::MetaspaceDCmd(outputStream* output, bool heap)
   : DCmdWithParser(output, heap)
   , _basic("basic", "Prints a basic summary (does not need a safepoint).", "BOOLEAN", false, "false")
   , _show_loaders("show-loaders", "Shows usage by class loader.", "BOOLEAN", false, "false")
+  , _show_classes("show-classes", "If show-loaders is set, shows loaded classes for each loader.", "BOOLEAN", false, "false")
   , _by_chunktype("by-chunktype", "Break down numbers by chunk type.", "BOOLEAN", false, "false")
   , _by_spacetype("by-spacetype", "Break down numbers by loader type.", "BOOLEAN", false, "false")
   , _show_vslist("vslist", "Shows details about the underlying virtual space.", "BOOLEAN", false, "false")
@@ -44,6 +46,7 @@ MetaspaceDCmd::MetaspaceDCmd(outputStream* output, bool heap)
 {
   _dcmdparser.add_dcmd_option(&_basic);
   _dcmdparser.add_dcmd_option(&_show_loaders);
+  _dcmdparser.add_dcmd_option(&_show_classes);
   _dcmdparser.add_dcmd_option(&_by_chunktype);
   _dcmdparser.add_dcmd_option(&_by_spacetype);
   _dcmdparser.add_dcmd_option(&_show_vslist);
@@ -87,6 +90,7 @@ void MetaspaceDCmd::execute(DCmdSource source, TRAPS) {
     // Full mode. Requires safepoint.
     int flags = 0;
     if (_show_loaders.value())         flags |= MetaspaceUtils::rf_show_loaders;
+    if (_show_classes.value())         flags |= MetaspaceUtils::rf_show_classes;
     if (_by_chunktype.value())         flags |= MetaspaceUtils::rf_break_down_by_chunktype;
     if (_by_spacetype.value())         flags |= MetaspaceUtils::rf_break_down_by_spacetype;
     if (_show_vslist.value())          flags |= MetaspaceUtils::rf_show_vslist;

src/hotspot/share/memory/metaspace/metaspaceDCmd.hpp

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, SAP and/or its affiliates.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -39,6 +40,7 @@ class MetaspaceDCmd : public DCmdWithParser {
   DCmdArgument<bool> _show_vslist;
   DCmdArgument<bool> _show_vsmap;
   DCmdArgument<char*> _scale;
+  DCmdArgument<bool> _show_classes;
 public:
   MetaspaceDCmd(outputStream* output, bool heap);
   static const char* name() {

src/hotspot/share/memory/metaspace/printCLDMetaspaceInfoClosure.cpp

@@ -25,6 +25,7 @@
 #include "classfile/classLoaderData.inline.hpp"
 #include "classfile/javaClasses.hpp"
 #include "memory/metaspace/printCLDMetaspaceInfoClosure.hpp"
+#include "memory/metaspace/printMetaspaceInfoKlassClosure.hpp"
 #include "memory/resourceArea.hpp"
 #include "runtime/safepoint.hpp"
 #include "utilities/globalDefinitions.hpp"
@@ -33,19 +34,31 @@
 
 namespace metaspace {
 
-PrintCLDMetaspaceInfoClosure::PrintCLDMetaspaceInfoClosure(outputStream* out, size_t scale, bool do_print, bool break_down_by_chunktype)
-: _out(out), _scale(scale), _do_print(do_print), _break_down_by_chunktype(break_down_by_chunktype)
-, _num_loaders(0)
+PrintCLDMetaspaceInfoClosure::PrintCLDMetaspaceInfoClosure(outputStream* out, size_t scale, bool do_print,
+    bool do_print_classes, bool break_down_by_chunktype)
+: _out(out), _scale(scale), _do_print(do_print), _do_print_classes(do_print_classes)
+, _break_down_by_chunktype(break_down_by_chunktype)
+, _num_loaders(0), _num_loaders_unloading(0), _num_loaders_without_metaspace(0)
 {
   memset(_num_loaders_by_spacetype, 0, sizeof(_num_loaders_by_spacetype));
 }
 
+static const char* classes_plural(uintx num) {
+  return num == 1 ? "" : "es";
+}
+
 void PrintCLDMetaspaceInfoClosure::do_cld(ClassLoaderData* cld) {
 
   assert(SafepointSynchronize::is_at_safepoint(), "Must be at a safepoint");
 
+  if (cld->is_unloading()) {
+    _num_loaders_unloading ++;
+    return;
+  }
+
   ClassLoaderMetaspace* msp = cld->metaspace_or_null();
   if (msp == NULL) {
+    _num_loaders_without_metaspace ++;
     return;
   }
 
@@ -99,6 +112,35 @@ void PrintCLDMetaspaceInfoClosure::do_cld(ClassLoaderData* cld) {
       _out->print(" instance of %s", class_name);
     }
 
+    if (_do_print_classes) {
+      streamIndentor sti(_out, 6);
+      _out->cr_indent();
+      _out->print("Loaded classes: ");
+      PrintMetaspaceInfoKlassClosure pkic(_out, true);
+      cld->classes_do(&pkic);
+      _out->cr_indent();
+      _out->print("-total-: ");
+      _out->print(UINTX_FORMAT " class%s", pkic._num_classes, classes_plural(pkic._num_classes));
+      if (pkic._num_instance_classes > 0 || pkic._num_array_classes > 0) {
+        _out->print(" (");
+        if (pkic._num_instance_classes > 0) {
+          _out->print(UINTX_FORMAT " instance class%s", pkic._num_instance_classes,
+              classes_plural(pkic._num_instance_classes));
+        }
+        if (pkic._num_array_classes > 0) {
+          if (pkic._num_instance_classes > 0) {
+            _out->print(", ");
+          }
+          _out->print(UINTX_FORMAT " array class%s", pkic._num_array_classes,
+              classes_plural(pkic._num_array_classes));
+        }
+        _out->print(").");
+      }
+    }
+
+    _out->cr();
+
+
     _out->cr();
 
     // Print statistics

src/hotspot/share/memory/metaspace/printCLDMetaspaceInfoClosure.hpp

@@ -39,17 +39,21 @@ private:
   outputStream* const _out;
   const size_t        _scale;
   const bool          _do_print;
+  const bool          _do_print_classes;
   const bool          _break_down_by_chunktype;
 
 public:
 
   uintx                           _num_loaders;
+  uintx                           _num_loaders_without_metaspace;
+  uintx                           _num_loaders_unloading;
   ClassLoaderMetaspaceStatistics  _stats_total;
 
   uintx                           _num_loaders_by_spacetype [Metaspace::MetaspaceTypeCount];
   ClassLoaderMetaspaceStatistics  _stats_by_spacetype [Metaspace::MetaspaceTypeCount];
 
-  PrintCLDMetaspaceInfoClosure(outputStream* out, size_t scale, bool do_print, bool break_down_by_chunktype);
+  PrintCLDMetaspaceInfoClosure(outputStream* out, size_t scale, bool do_print,
+      bool do_print_classes, bool break_down_by_chunktype);
   void do_cld(ClassLoaderData* cld);
 
 };

src/hotspot/share/memory/metaspace/printMetaspaceInfoKlassClosure.cpp

@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, SAP and/or its affiliates.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+#include "precompiled.hpp"
+
+#include "classfile/systemDictionary.hpp"
+#include "memory/metaspace/printMetaspaceInfoKlassClosure.hpp"
+#include "memory/resourceArea.hpp"
+#include "oops/constantPool.inline.hpp"
+#include "oops/instanceKlass.hpp"
+#include "oops/klass.hpp"
+#include "utilities/constantTag.hpp"
+#include "utilities/globalDefinitions.hpp"
+#include "utilities/ostream.hpp"
+
+
+namespace metaspace {
+
+PrintMetaspaceInfoKlassClosure::PrintMetaspaceInfoKlassClosure(outputStream* out, bool do_print)
+: _out(out), _do_print(do_print)
+, _num_classes(0), _num_instance_classes(0), _num_array_classes(0) {
+}
+
+void PrintMetaspaceInfoKlassClosure::do_klass(Klass* k) {
+  _num_classes ++;
+  if (k->is_instance_klass()) {
+    _num_instance_classes ++;
+  } else if (k->is_array_klass()) {
+    _num_array_classes ++;
+  }
+  if (_do_print) {
+    _out->cr_indent();
+    _out->print(UINTX_FORMAT_W(4) ": ", _num_classes);
+    ResourceMark rm;
+    _out->print("%s", k->external_name());
+  }
+}
+
+} // namespace metaspace

src/hotspot/share/memory/metaspace/printMetaspaceInfoKlassClosure.hpp

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, SAP and/or its affiliates.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_MEMORY_METASPACE_PRINTMETASPACEINFOKLASSCLOSURE_HPP_
+#define SHARE_MEMORY_METASPACE_PRINTMETASPACEINFOKLASSCLOSURE_HPP_
+
+#include "memory/iterator.hpp"
+#include "utilities/globalDefinitions.hpp"
+
+class outputStream;
+class InstanceKlass;
+
+namespace metaspace {
+
+// Helper class for MetaspaceUtils::print_report()
+class PrintMetaspaceInfoKlassClosure : public KlassClosure {
+private:
+  outputStream* const _out;
+  const bool          _do_print;
+
+public:
+  uintx _num_classes;
+  uintx _num_instance_classes;
+  uintx _num_array_classes;
+
+  PrintMetaspaceInfoKlassClosure(outputStream* out, bool do_print);
+  void do_klass(Klass* k);
+
+}; // end: PrintKlassInfoClosure
+
+} // namespace metaspace
+
+#endif /* SHARE_MEMORY_METASPACE_PRINTMETASPACEINFOKLASSCLOSURE_HPP_ */