1 /*
   2  * Copyright (c) 2014, 2017, 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 #ifndef SHARE_VM_CLASSFILE_CLASSLOADERSTATS_HPP
  26 #define SHARE_VM_CLASSFILE_CLASSLOADERSTATS_HPP
  27 
  28 
  29 #include "classfile/classLoaderData.hpp"
  30 #include "oops/klass.hpp"

  31 #include "oops/oopsHierarchy.hpp"
  32 #include "runtime/vm_operations.hpp"
  33 #include "services/diagnosticCommand.hpp"
  34 #include "utilities/resourceHash.hpp"
  35 
  36 
  37 class ClassLoaderStatsDCmd : public DCmd {
  38 public:
  39   ClassLoaderStatsDCmd(outputStream* output, bool heap) :
  40     DCmd(output, heap) {
  41   }
  42 
  43   static const char* name() {
  44     return "VM.classloader_stats";
  45   }
  46 
  47   static const char* description() {
  48     return "Print statistics about all ClassLoaders.";
  49   }
  50 
  51   static const char* impact() {
  52     return "Low";
  53   }
  54 
  55   virtual void execute(DCmdSource source, TRAPS);
  56 
  57   static int num_arguments() {
  58     return 0;
  59   }
  60 
  61   static const JavaPermission permission() {
  62     JavaPermission p = {"java.lang.management.ManagementPermission",
  63                         "monitor", NULL};
  64     return p;
  65   }
  66 };
  67 
  68 
  69 class ClassLoaderStats : public ResourceObj {
  70 public:
  71   ClassLoaderData*  _cld;
  72   oop               _class_loader;
  73   oop               _parent;
  74 
  75   size_t            _chunk_sz;
  76   size_t            _block_sz;
  77   uintx             _classes_count;
  78 
  79   size_t            _anon_chunk_sz;
  80   size_t            _anon_block_sz;
  81   uintx             _anon_classes_count;
  82 
  83   ClassLoaderStats() :
  84     _cld(0),
  85     _class_loader(0),
  86     _parent(0),
  87     _chunk_sz(0),
  88     _block_sz(0),
  89     _classes_count(0),
  90     _anon_block_sz(0),
  91     _anon_chunk_sz(0),
  92     _anon_classes_count(0) {
  93   }
  94 };
  95 
  96 
  97 class ClassLoaderStatsClosure : public CLDClosure {
  98 protected:
  99   static bool oop_equals(oop const& s1, oop const& s2) {
 100     return s1 == s2;
 101   }
 102 
 103   static unsigned oop_hash(oop const& s1) {
 104     // Robert Jenkins 1996 & Thomas Wang 1997
 105     // http://web.archive.org/web/20071223173210/http://www.concentric.net/~Ttwang/tech/inthash.htm
 106     uintptr_t tmp = cast_from_oop<uintptr_t>(s1);
 107     unsigned hash = (unsigned)tmp;
 108     hash = ~hash + (hash << 15);
 109     hash = hash ^ (hash >> 12);
 110     hash = hash + (hash << 2);
 111     hash = hash ^ (hash >> 4);
 112     hash = hash * 2057;
 113     hash = hash ^ (hash >> 16);
 114     return hash;
 115   }
 116 
 117   typedef ResourceHashtable<oop, ClassLoaderStats*,
 118       ClassLoaderStatsClosure::oop_hash, ClassLoaderStatsClosure::oop_equals> StatsTable;
 119 
 120   outputStream* _out;
 121   StatsTable* _stats;
 122   uintx   _total_loaders;
 123   uintx   _total_classes;
 124   size_t  _total_chunk_sz;
 125   size_t  _total_block_sz;
 126 
 127 public:
 128   ClassLoaderStatsClosure(outputStream* out) :
 129     _out(out),
 130     _total_loaders(0),
 131     _total_block_sz(0),
 132     _total_chunk_sz(0),
 133     _total_classes(0),
 134     _stats(new StatsTable()) {
 135   }
 136 
 137   virtual void do_cld(ClassLoaderData* cld);
 138   virtual bool do_entry(oop const& key, ClassLoaderStats* const& cls);
 139   void print();
 140 
 141 private:
 142   void addEmptyParents(oop cl);
 143 };
 144 
 145 
 146 class ClassLoaderStatsVMOperation : public VM_Operation {
 147   outputStream* _out;
 148 
 149 public:
 150   ClassLoaderStatsVMOperation(outputStream* out) :
 151     _out(out) {
 152   }
 153 
 154   VMOp_Type type() const {
 155     return VMOp_ClassLoaderStatsOperation;
 156   }
 157 
 158   void doit();
 159 };
 160 
 161 #endif // SHARE_VM_CLASSFILE_CLASSLOADERSTATS_HPP
--- EOF ---