1 /* 2 * Copyright (c) 2002, 2020, 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_MEMORY_HEAPINSPECTION_HPP 26 #define SHARE_MEMORY_HEAPINSPECTION_HPP 27 28 #include "memory/allocation.hpp" 29 #include "oops/objArrayOop.hpp" 30 #include "oops/oop.hpp" 31 #include "oops/annotations.hpp" 32 #include "utilities/macros.hpp" 33 #include "gc/shared/workgroup.hpp" 34 35 class ParallelObjectIterator; 36 37 #if INCLUDE_SERVICES 38 39 40 // HeapInspection 41 42 // KlassInfoTable is a bucket hash table that 43 // maps Klass*s to extra information: 44 // instance count and instance word size. 45 // 46 // A KlassInfoBucket is the head of a link list 47 // of KlassInfoEntry's 48 // 49 // KlassInfoHisto is a growable array of pointers 50 // to KlassInfoEntry's and is used to sort 51 // the entries. 52 53 class KlassInfoEntry: public CHeapObj<mtInternal> { 54 private: 55 KlassInfoEntry* _next; 56 Klass* _klass; 57 long _instance_count; 58 size_t _instance_words; 59 long _index; 60 bool _do_print; // True if we should print this class when printing the class hierarchy. 61 GrowableArray<KlassInfoEntry*>* _subclasses; 62 63 public: 64 KlassInfoEntry(Klass* k, KlassInfoEntry* next) : 65 _next(next), _klass(k), _instance_count(0), _instance_words(0), _index(-1), 66 _do_print(false), _subclasses(NULL) 67 {} 68 ~KlassInfoEntry(); 69 KlassInfoEntry* next() const { return _next; } 70 bool is_equal(const Klass* k) { return k == _klass; } 71 Klass* klass() const { return _klass; } 72 long count() const { return _instance_count; } 73 void set_count(long ct) { _instance_count = ct; } 74 size_t words() const { return _instance_words; } 75 void set_words(size_t wds) { _instance_words = wds; } 76 void set_index(long index) { _index = index; } 77 long index() const { return _index; } 78 GrowableArray<KlassInfoEntry*>* subclasses() const { return _subclasses; } 79 void add_subclass(KlassInfoEntry* cie); 80 void set_do_print(bool do_print) { _do_print = do_print; } 81 bool do_print() const { return _do_print; } 82 int compare(KlassInfoEntry* e1, KlassInfoEntry* e2); 83 void print_on(outputStream* st) const; 84 const char* name() const; 85 }; 86 87 class KlassInfoClosure : public StackObj { 88 public: 89 // Called for each KlassInfoEntry. 90 virtual void do_cinfo(KlassInfoEntry* cie) = 0; 91 }; 92 93 class KlassInfoBucket: public CHeapObj<mtInternal> { 94 private: 95 KlassInfoEntry* _list; 96 KlassInfoEntry* list() { return _list; } 97 void set_list(KlassInfoEntry* l) { _list = l; } 98 public: 99 KlassInfoEntry* lookup(Klass* k); 100 void initialize() { _list = NULL; } 101 void empty(); 102 void iterate(KlassInfoClosure* cic); 103 }; 104 105 class KlassInfoTable: public StackObj { 106 private: 107 static const int _num_buckets = 20011; 108 size_t _size_of_instances_in_words; 109 110 // An aligned reference address (typically the least 111 // address in the perm gen) used for hashing klass 112 // objects. 113 HeapWord* _ref; 114 115 KlassInfoBucket* _buckets; 116 uint hash(const Klass* p); 117 KlassInfoEntry* lookup(Klass* k); // allocates if not found! 118 119 class AllClassesFinder; 120 121 public: 122 KlassInfoTable(bool add_all_classes); 123 ~KlassInfoTable(); 124 bool record_instance(const oop obj); 125 void iterate(KlassInfoClosure* cic); 126 bool allocation_failed() { return _buckets == NULL; } 127 size_t size_of_instances_in_words() const; 128 bool merge(KlassInfoTable* table); 129 bool merge_entry(const KlassInfoEntry* cie); 130 131 friend class KlassInfoHisto; 132 friend class KlassHierarchy; 133 }; 134 135 class KlassHierarchy : AllStatic { 136 public: 137 static void print_class_hierarchy(outputStream* st, bool print_interfaces, bool print_subclasses, 138 char* classname); 139 140 private: 141 static void set_do_print_for_class_hierarchy(KlassInfoEntry* cie, KlassInfoTable* cit, 142 bool print_subclasse); 143 static void print_class(outputStream* st, KlassInfoEntry* cie, bool print_subclasses); 144 }; 145 146 class KlassInfoHisto : public StackObj { 147 private: 148 static const int _histo_initial_size = 1000; 149 KlassInfoTable *_cit; 150 GrowableArray<KlassInfoEntry*>* _elements; 151 GrowableArray<KlassInfoEntry*>* elements() const { return _elements; } 152 static int sort_helper(KlassInfoEntry** e1, KlassInfoEntry** e2); 153 void print_elements(outputStream* st) const; 154 bool is_selected(const char *col_name); 155 156 template <class T> static int count_bytes(T* x) { 157 return (HeapWordSize * ((x) ? (x)->size() : 0)); 158 } 159 160 template <class T> static int count_bytes_array(T* x) { 161 if (x == NULL) { 162 return 0; 163 } 164 if (x->length() == 0) { 165 // This is a shared array, e.g., Universe::the_empty_int_array(). Don't 166 // count it to avoid double-counting. 167 return 0; 168 } 169 return HeapWordSize * x->size(); 170 } 171 172 static void print_julong(outputStream* st, int width, julong n) { 173 int num_spaces = width - julong_width(n); 174 if (num_spaces > 0) { 175 st->print("%*s", num_spaces, ""); 176 } 177 st->print(JULONG_FORMAT, n); 178 } 179 180 static int julong_width(julong n) { 181 if (n == 0) { 182 return 1; 183 } 184 int w = 0; 185 while (n > 0) { 186 n /= 10; 187 w += 1; 188 } 189 return w; 190 } 191 192 static int col_width(julong n, const char *name) { 193 int w = julong_width(n); 194 int min = (int)(strlen(name)); 195 if (w < min) { 196 w = min; 197 } 198 // add a leading space for separation. 199 return w + 1; 200 } 201 202 public: 203 KlassInfoHisto(KlassInfoTable* cit); 204 ~KlassInfoHisto(); 205 void add(KlassInfoEntry* cie); 206 void print_histo_on(outputStream* st); 207 void sort(); 208 }; 209 210 #endif // INCLUDE_SERVICES 211 212 // These declarations are needed since the declaration of KlassInfoTable and 213 // KlassInfoClosure are guarded by #if INLCUDE_SERVICES 214 class KlassInfoTable; 215 class KlassInfoClosure; 216 217 class HeapInspection : public StackObj { 218 public: 219 void heap_inspection(outputStream* st, size_t parallel_thread_num = 1) NOT_SERVICES_RETURN; 220 size_t populate_table(KlassInfoTable* cit, BoolObjectClosure* filter = NULL, size_t parallel_thread_num = 1) NOT_SERVICES_RETURN_(0); 221 static void find_instances_at_safepoint(Klass* k, GrowableArray<oop>* result) NOT_SERVICES_RETURN; 222 private: 223 void iterate_over_heap(KlassInfoTable* cit, BoolObjectClosure* filter = NULL); 224 }; 225 226 class ParHeapInspectTask : public AbstractGangTask { 227 private: 228 ParallelObjectIterator* _poi; 229 KlassInfoTable* _shared_cit; 230 BoolObjectClosure* _filter; 231 size_t _shared_missed_count; 232 bool _success; 233 Mutex _mutex; 234 235 public: 236 ParHeapInspectTask(ParallelObjectIterator* poi, 237 KlassInfoTable* shared_cit, 238 BoolObjectClosure* filter) : 239 AbstractGangTask("Iterating heap"), 240 _poi(poi), 241 _shared_cit(shared_cit), 242 _filter(filter), 243 _shared_missed_count(0), 244 _success(true), 245 _mutex(Mutex::leaf, "Parallel heap iteration data merge lock") {} 246 247 uint missed_count() const { 248 return _shared_missed_count; 249 } 250 251 virtual void work(uint worker_id); 252 }; 253 254 #endif // SHARE_MEMORY_HEAPINSPECTION_HPP