1 /*
  2  * Copyright (c) 2014, 2025, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #include "classfile/classLoaderData.inline.hpp"
 26 #include "classfile/classLoaderDataGraph.hpp"
 27 #include "classfile/classLoaderStats.hpp"
 28 #include "memory/classLoaderMetaspace.hpp"
 29 #include "oops/objArrayKlass.hpp"
 30 #include "oops/oop.inline.hpp"
 31 #include "utilities/globalDefinitions.hpp"
 32 
 33 
 34 class ClassStatsClosure : public KlassClosure {







 35 public:
 36   int _num_classes;
 37 
 38   ClassStatsClosure() :
 39     _num_classes(0) {
 40   }
 41 
 42   virtual void do_klass(Klass* k) {
 43     _num_classes++;


 44   }

 45 };
 46 
 47 void ClassLoaderStatsClosure::do_cld(ClassLoaderData* cld) {
 48   // Class loaders are not kept alive so this closure must only be
 49   // used during a safepoint.
 50   assert_at_safepoint();
 51   oop cl = cld->class_loader_no_keepalive();
 52 
 53   // The hashtable key is the ClassLoader oop since we want to account
 54   // for "real" classes and hidden classes together
 55   bool added = false;
 56   ClassLoaderStats* cls = _stats->put_if_absent(cl, &added);
 57   if (added) {
 58     cls->_class_loader = cl;
 59     _total_loaders++;
 60   }
 61   assert(cls->_class_loader == cl, "Sanity");
 62 
 63   if (!cld->has_class_mirror_holder()) {
 64     cls->_cld = cld;
 65   }
 66 
 67   if (cl != nullptr) {
 68     cls->_parent = java_lang_ClassLoader::parent_no_keepalive(cl);
 69     addEmptyParents(cls->_parent);
 70   }
 71 
 72   ClassStatsClosure csc;
 73   cld->classes_do(&csc);
 74   bool is_hidden = false;
 75   if(cld->has_class_mirror_holder()) {
 76     // If cld has a class holder then it must be hidden.
 77     // Either way, count it as a hidden class.
 78     cls->_hidden_classes_count += csc._num_classes;
 79   } else {
 80     cls->_classes_count = csc._num_classes;
 81   }
 82   _total_classes += csc._num_classes;
 83 
 84   ClassLoaderMetaspace* ms = cld->metaspace_or_null();
 85   if (ms != nullptr) {
 86     size_t used_words, capacity_words;
 87     ms->usage_numbers(&used_words, nullptr, &capacity_words);
 88     size_t used_bytes = used_words * BytesPerWord;
 89     size_t capacity_bytes = capacity_words * BytesPerWord;
 90     if(cld->has_class_mirror_holder()) {
 91       cls->_hidden_chunk_sz += capacity_bytes;
 92       cls->_hidden_block_sz += used_bytes;
 93     } else {
 94       cls->_chunk_sz = capacity_bytes;
 95       cls->_block_sz = used_bytes;
 96     }
 97     _total_chunk_sz += capacity_bytes;
 98     _total_block_sz += used_bytes;
 99   }
100 }
101 
102 // Handles the difference in pointer width on 32 and 64 bit platforms
103 #ifdef _LP64
104   #define SPACE "%8s"
105 #else
106   #define SPACE "%s"
107 #endif
108 
109 
110 bool ClassLoaderStatsClosure::do_entry(oop const& key, ClassLoaderStats const& cls) {
111   Klass* class_loader_klass = (cls._class_loader == nullptr ? nullptr : cls._class_loader->klass());
112   Klass* parent_klass = (cls._parent == nullptr ? nullptr : cls._parent->klass());
113 
114   _out->print(INTPTR_FORMAT "  " INTPTR_FORMAT "  " INTPTR_FORMAT "  %6zu  %8zu  %8zu  ",
115       p2i(class_loader_klass), p2i(parent_klass), p2i(cls._cld),
116       cls._classes_count,
117       cls._chunk_sz, cls._block_sz);
118   if (class_loader_klass != nullptr) {
119     _out->print("%s", class_loader_klass->external_name());
120   } else {
121     _out->print("<boot class loader>");
122   }
123   _out->cr();
124   if (cls._hidden_classes_count > 0) {
125     _out->print_cr(SPACE SPACE SPACE "                                    %6zu  %8zu  %8zu   + hidden classes",
126         "", "", "",
127         cls._hidden_classes_count,
128         cls._hidden_chunk_sz, cls._hidden_block_sz);
129   }
130   return true;
131 }
132 
133 
134 void ClassLoaderStatsClosure::print() {
135   _out->print_cr("ClassLoader" SPACE " Parent" SPACE "      CLD*" SPACE "       Classes   ChunkSz   BlockSz  Type", "", "", "");
136   _stats->iterate(this);
137   _out->print("Total = %-6zu", _total_loaders);
138   _out->print(SPACE SPACE SPACE "                      ", "", "", "");
139   _out->print_cr("%6zu  %8zu  %8zu  ",
140       _total_classes,
141       _total_chunk_sz,
142       _total_block_sz);
143   _out->print_cr("ChunkSz: Total size of all allocated metaspace chunks");
144   _out->print_cr("BlockSz: Total size of all allocated metaspace blocks (each chunk has several blocks)");
145 }
146 
147 
148 void ClassLoaderStatsClosure::addEmptyParents(oop cl) {
149   while (cl != nullptr && java_lang_ClassLoader::loader_data_acquire(cl) == nullptr) {
150     // This classloader has not loaded any classes
151     bool added = false;
152     ClassLoaderStats* cls = _stats->put_if_absent(cl, &added);
153     if (added) {
154       cls->_class_loader = cl;
155       cls->_parent = java_lang_ClassLoader::parent_no_keepalive(cl);
156       _total_loaders++;
157     }
158     assert(cls->_class_loader == cl, "Sanity");
159 
160     cl = java_lang_ClassLoader::parent_no_keepalive(cl);
161   }
162 }
163 
164 
165 void ClassLoaderStatsVMOperation::doit() {
166   ClassLoaderStatsClosure clsc (_out);
167   ClassLoaderDataGraph::loaded_cld_do(&clsc);
168   clsc.print();
169 }
170 
171 
172 void ClassLoaderStatsDCmd::execute(DCmdSource source, TRAPS) {
173   ClassLoaderStatsVMOperation op(output());
174   VMThread::execute(&op);
175 }
--- EOF ---