1 /* 2 * Copyright (c) 2003, 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 #include "precompiled.hpp" 26 #include "classfile/classLoaderData.inline.hpp" 27 #include "classfile/sharedClassUtil.hpp" 28 #include "classfile/dictionary.hpp" 29 #include "classfile/systemDictionary.hpp" 30 #include "classfile/systemDictionaryShared.hpp" 31 #include "memory/iterator.hpp" 32 #include "memory/resourceArea.hpp" 33 #include "oops/oop.inline.hpp" 34 #include "runtime/orderAccess.inline.hpp" 35 #include "utilities/hashtable.inline.hpp" 36 37 DictionaryEntry* Dictionary::_current_class_entry = NULL; 38 int Dictionary::_current_class_index = 0; 39 40 size_t Dictionary::entry_size() { 41 if (DumpSharedSpaces) { 42 return SystemDictionaryShared::dictionary_entry_size(); 43 } else { 44 return sizeof(DictionaryEntry); 45 } 46 } 47 48 Dictionary::Dictionary(int table_size) 49 : TwoOopHashtable<InstanceKlass*, mtClass>(table_size, (int)entry_size()) { 50 _current_class_index = 0; 51 _current_class_entry = NULL; 52 _pd_cache_table = new ProtectionDomainCacheTable(defaultProtectionDomainCacheSize); 53 }; 54 55 56 Dictionary::Dictionary(int table_size, HashtableBucket<mtClass>* t, 57 int number_of_entries) 58 : TwoOopHashtable<InstanceKlass*, mtClass>(table_size, (int)entry_size(), t, number_of_entries) { 59 _current_class_index = 0; 60 _current_class_entry = NULL; 61 _pd_cache_table = new ProtectionDomainCacheTable(defaultProtectionDomainCacheSize); 62 }; 63 64 ProtectionDomainCacheEntry* Dictionary::cache_get(Handle protection_domain) { 65 return _pd_cache_table->get(protection_domain); 66 } 67 68 DictionaryEntry* Dictionary::new_entry(unsigned int hash, InstanceKlass* klass, 69 ClassLoaderData* loader_data) { 70 DictionaryEntry* entry = (DictionaryEntry*)Hashtable<InstanceKlass*, mtClass>::new_entry(hash, klass); 71 entry->set_loader_data(loader_data); 72 entry->set_pd_set(NULL); 73 assert(klass->is_instance_klass(), "Must be"); 74 if (DumpSharedSpaces) { 75 SystemDictionaryShared::init_shared_dictionary_entry(klass, entry); 76 } 77 return entry; 78 } 79 80 81 void Dictionary::free_entry(DictionaryEntry* entry) { 82 // avoid recursion when deleting linked list 83 while (entry->pd_set() != NULL) { 84 ProtectionDomainEntry* to_delete = entry->pd_set(); 85 entry->set_pd_set(to_delete->next()); 86 delete to_delete; 87 } 88 Hashtable<InstanceKlass*, mtClass>::free_entry(entry); 89 } 90 91 92 bool DictionaryEntry::contains_protection_domain(oop protection_domain) const { 93 #ifdef ASSERT 94 if (protection_domain == klass()->protection_domain()) { 95 // Ensure this doesn't show up in the pd_set (invariant) 96 bool in_pd_set = false; 97 for (ProtectionDomainEntry* current = _pd_set; 98 current != NULL; 99 current = current->next()) { 100 if (current->protection_domain() == protection_domain) { 101 in_pd_set = true; 102 break; 103 } 104 } 105 if (in_pd_set) { 106 assert(false, "A klass's protection domain should not show up " 107 "in its sys. dict. PD set"); 108 } 109 } 110 #endif /* ASSERT */ 111 112 if (protection_domain == klass()->protection_domain()) { 113 // Succeeds trivially 114 return true; 115 } 116 117 for (ProtectionDomainEntry* current = _pd_set; 118 current != NULL; 119 current = current->next()) { 120 if (current->protection_domain() == protection_domain) return true; 121 } 122 return false; 123 } 124 125 126 void DictionaryEntry::add_protection_domain(Dictionary* dict, Handle protection_domain) { 127 assert_locked_or_safepoint(SystemDictionary_lock); 128 if (!contains_protection_domain(protection_domain())) { 129 ProtectionDomainCacheEntry* entry = dict->cache_get(protection_domain); 130 ProtectionDomainEntry* new_head = 131 new ProtectionDomainEntry(entry, _pd_set); 132 // Warning: Preserve store ordering. The SystemDictionary is read 133 // without locks. The new ProtectionDomainEntry must be 134 // complete before other threads can be allowed to see it 135 // via a store to _pd_set. 136 OrderAccess::release_store_ptr(&_pd_set, new_head); 137 } 138 if (log_is_enabled(Trace, protectiondomain)) { 139 ResourceMark rm; 140 outputStream* log = Log(protectiondomain)::trace_stream(); 141 print_count(log); 142 } 143 } 144 145 146 void Dictionary::do_unloading() { 147 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint"); 148 149 // Remove unloadable entries and classes from system dictionary 150 // The placeholder array has been handled in always_strong_oops_do. 151 DictionaryEntry* probe = NULL; 152 for (int index = 0; index < table_size(); index++) { 153 for (DictionaryEntry** p = bucket_addr(index); *p != NULL; ) { 154 probe = *p; 155 Klass* e = probe->klass(); 156 ClassLoaderData* loader_data = probe->loader_data(); 157 158 InstanceKlass* ik = InstanceKlass::cast(e); 159 160 // Non-unloadable classes were handled in always_strong_oops_do 161 if (!is_strongly_reachable(loader_data, e)) { 162 // Entry was not visited in phase1 (negated test from phase1) 163 assert(!loader_data->is_the_null_class_loader_data(), "unloading entry with null class loader"); 164 ClassLoaderData* k_def_class_loader_data = ik->class_loader_data(); 165 166 // Do we need to delete this system dictionary entry? 167 bool purge_entry = false; 168 169 // Do we need to delete this system dictionary entry? 170 if (loader_data->is_unloading()) { 171 // If the loader is not live this entry should always be 172 // removed (will never be looked up again). 173 purge_entry = true; 174 } else { 175 // The loader in this entry is alive. If the klass is dead, 176 // (determined by checking the defining class loader) 177 // the loader must be an initiating loader (rather than the 178 // defining loader). Remove this entry. 179 if (k_def_class_loader_data->is_unloading()) { 180 // If we get here, the class_loader_data must not be the defining 181 // loader, it must be an initiating one. 182 assert(k_def_class_loader_data != loader_data, 183 "cannot have live defining loader and unreachable klass"); 184 // Loader is live, but class and its defining loader are dead. 185 // Remove the entry. The class is going away. 186 purge_entry = true; 187 } 188 } 189 190 if (purge_entry) { 191 *p = probe->next(); 192 if (probe == _current_class_entry) { 193 _current_class_entry = NULL; 194 } 195 free_entry(probe); 196 continue; 197 } 198 } 199 p = probe->next_addr(); 200 } 201 } 202 } 203 204 void Dictionary::roots_oops_do(OopClosure* strong, OopClosure* weak) { 205 // Do strong roots marking if the closures are the same. 206 if (strong == weak || !ClassUnloading) { 207 // Only the protection domain oops contain references into the heap. Iterate 208 // over all of them. 209 _pd_cache_table->oops_do(strong); 210 } else { 211 if (weak != NULL) { 212 _pd_cache_table->oops_do(weak); 213 } 214 } 215 } 216 217 void Dictionary::remove_classes_in_error_state() { 218 assert(DumpSharedSpaces, "supported only when dumping"); 219 DictionaryEntry* probe = NULL; 220 for (int index = 0; index < table_size(); index++) { 221 for (DictionaryEntry** p = bucket_addr(index); *p != NULL; ) { 222 probe = *p; 223 InstanceKlass* ik = InstanceKlass::cast(probe->klass()); 224 if (ik->is_in_error_state()) { // purge this entry 225 *p = probe->next(); 226 if (probe == _current_class_entry) { 227 _current_class_entry = NULL; 228 } 229 free_entry(probe); 230 ResourceMark rm; 231 tty->print_cr("Preload Warning: Removed error class: %s", ik->external_name()); 232 continue; 233 } 234 235 p = probe->next_addr(); 236 } 237 } 238 } 239 240 void Dictionary::always_strong_oops_do(OopClosure* blk) { 241 // Then iterate over the protection domain cache to apply the closure on the 242 // previously marked ones. 243 _pd_cache_table->oops_do(blk); 244 } 245 246 void Dictionary::oops_do(OopClosure* f) { 247 _pd_cache_table->oops_do(f); 248 } 249 250 void Dictionary::always_strong_classes_do(KlassClosure* closure) { 251 // Follow all system classes and temporary placeholders in dictionary 252 for (int index = 0; index < table_size(); index++) { 253 for (DictionaryEntry* probe = bucket(index); 254 probe != NULL; 255 probe = probe->next()) { 256 Klass* e = probe->klass(); 257 ClassLoaderData* loader_data = probe->loader_data(); 258 if (is_strongly_reachable(loader_data, e)) { 259 closure->do_klass(e); 260 } 261 } 262 } 263 } 264 265 266 // Just the classes from defining class loaders 267 void Dictionary::classes_do(void f(Klass*)) { 268 for (int index = 0; index < table_size(); index++) { 269 for (DictionaryEntry* probe = bucket(index); 270 probe != NULL; 271 probe = probe->next()) { 272 Klass* k = probe->klass(); 273 if (probe->loader_data() == k->class_loader_data()) { 274 f(k); 275 } 276 } 277 } 278 } 279 280 // Added for initialize_itable_for_klass to handle exceptions 281 // Just the classes from defining class loaders 282 void Dictionary::classes_do(void f(Klass*, TRAPS), TRAPS) { 283 for (int index = 0; index < table_size(); index++) { 284 for (DictionaryEntry* probe = bucket(index); 285 probe != NULL; 286 probe = probe->next()) { 287 Klass* k = probe->klass(); 288 if (probe->loader_data() == k->class_loader_data()) { 289 f(k, CHECK); 290 } 291 } 292 } 293 } 294 295 // All classes, and their class loaders 296 // Don't iterate over placeholders 297 void Dictionary::classes_do(void f(Klass*, ClassLoaderData*)) { 298 for (int index = 0; index < table_size(); index++) { 299 for (DictionaryEntry* probe = bucket(index); 300 probe != NULL; 301 probe = probe->next()) { 302 Klass* k = probe->klass(); 303 f(k, probe->loader_data()); 304 } 305 } 306 } 307 308 void Dictionary::methods_do(void f(Method*)) { 309 for (int index = 0; index < table_size(); index++) { 310 for (DictionaryEntry* probe = bucket(index); 311 probe != NULL; 312 probe = probe->next()) { 313 Klass* k = probe->klass(); 314 if (probe->loader_data() == k->class_loader_data()) { 315 // only take klass is we have the entry with the defining class loader 316 InstanceKlass::cast(k)->methods_do(f); 317 } 318 } 319 } 320 } 321 322 void Dictionary::unlink(BoolObjectClosure* is_alive) { 323 // Only the protection domain cache table may contain references to the heap 324 // that need to be unlinked. 325 _pd_cache_table->unlink(is_alive); 326 } 327 328 InstanceKlass* Dictionary::try_get_next_class() { 329 while (true) { 330 if (_current_class_entry != NULL) { 331 InstanceKlass* k = _current_class_entry->klass(); 332 _current_class_entry = _current_class_entry->next(); 333 return k; 334 } 335 _current_class_index = (_current_class_index + 1) % table_size(); 336 _current_class_entry = bucket(_current_class_index); 337 } 338 // never reached 339 } 340 341 // Add a loaded class to the system dictionary. 342 // Readers of the SystemDictionary aren't always locked, so _buckets 343 // is volatile. The store of the next field in the constructor is 344 // also cast to volatile; we do this to ensure store order is maintained 345 // by the compilers. 346 347 void Dictionary::add_klass(Symbol* class_name, ClassLoaderData* loader_data, 348 InstanceKlass* obj) { 349 assert_locked_or_safepoint(SystemDictionary_lock); 350 assert(obj != NULL, "adding NULL obj"); 351 assert(obj->name() == class_name, "sanity check on name"); 352 assert(loader_data != NULL, "Must be non-NULL"); 353 354 unsigned int hash = compute_hash(class_name, loader_data); 355 int index = hash_to_index(hash); 356 DictionaryEntry* entry = new_entry(hash, obj, loader_data); 357 add_entry(index, entry); 358 } 359 360 361 // This routine does not lock the system dictionary. 362 // 363 // Since readers don't hold a lock, we must make sure that system 364 // dictionary entries are only removed at a safepoint (when only one 365 // thread is running), and are added to in a safe way (all links must 366 // be updated in an MT-safe manner). 367 // 368 // Callers should be aware that an entry could be added just after 369 // _buckets[index] is read here, so the caller will not see the new entry. 370 DictionaryEntry* Dictionary::get_entry(int index, unsigned int hash, 371 Symbol* class_name, 372 ClassLoaderData* loader_data) { 373 DEBUG_ONLY(_lookup_count++); 374 for (DictionaryEntry* entry = bucket(index); 375 entry != NULL; 376 entry = entry->next()) { 377 if (entry->hash() == hash && entry->equals(class_name, loader_data)) { 378 DEBUG_ONLY(bucket_count_hit(index)); 379 return entry; 380 } 381 DEBUG_ONLY(_lookup_length++); 382 } 383 return NULL; 384 } 385 386 387 InstanceKlass* Dictionary::find(int index, unsigned int hash, Symbol* name, 388 ClassLoaderData* loader_data, Handle protection_domain, TRAPS) { 389 DictionaryEntry* entry = get_entry(index, hash, name, loader_data); 390 if (entry != NULL && entry->is_valid_protection_domain(protection_domain)) { 391 return entry->klass(); 392 } else { 393 return NULL; 394 } 395 } 396 397 398 InstanceKlass* Dictionary::find_class(int index, unsigned int hash, 399 Symbol* name, ClassLoaderData* loader_data) { 400 assert_locked_or_safepoint(SystemDictionary_lock); 401 assert (index == index_for(name, loader_data), "incorrect index?"); 402 403 DictionaryEntry* entry = get_entry(index, hash, name, loader_data); 404 return (entry != NULL) ? entry->klass() : NULL; 405 } 406 407 408 // Variant of find_class for shared classes. No locking required, as 409 // that table is static. 410 411 InstanceKlass* Dictionary::find_shared_class(int index, unsigned int hash, 412 Symbol* name) { 413 assert (index == index_for(name, NULL), "incorrect index?"); 414 415 DictionaryEntry* entry = get_entry(index, hash, name, NULL); 416 return (entry != NULL) ? entry->klass() : NULL; 417 } 418 419 420 void Dictionary::add_protection_domain(int index, unsigned int hash, 421 InstanceKlass* klass, 422 ClassLoaderData* loader_data, Handle protection_domain, 423 TRAPS) { 424 Symbol* klass_name = klass->name(); 425 DictionaryEntry* entry = get_entry(index, hash, klass_name, loader_data); 426 427 assert(entry != NULL,"entry must be present, we just created it"); 428 assert(protection_domain() != NULL, 429 "real protection domain should be present"); 430 431 entry->add_protection_domain(this, protection_domain); 432 433 assert(entry->contains_protection_domain(protection_domain()), 434 "now protection domain should be present"); 435 } 436 437 438 bool Dictionary::is_valid_protection_domain(int index, unsigned int hash, 439 Symbol* name, 440 ClassLoaderData* loader_data, 441 Handle protection_domain) { 442 DictionaryEntry* entry = get_entry(index, hash, name, loader_data); 443 return entry->is_valid_protection_domain(protection_domain); 444 } 445 446 447 void Dictionary::reorder_dictionary() { 448 449 // Copy all the dictionary entries into a single master list. 450 451 DictionaryEntry* master_list = NULL; 452 for (int i = 0; i < table_size(); ++i) { 453 DictionaryEntry* p = bucket(i); 454 while (p != NULL) { 455 DictionaryEntry* tmp; 456 tmp = p->next(); 457 p->set_next(master_list); 458 master_list = p; 459 p = tmp; 460 } 461 set_entry(i, NULL); 462 } 463 464 // Add the dictionary entries back to the list in the correct buckets. 465 while (master_list != NULL) { 466 DictionaryEntry* p = master_list; 467 master_list = master_list->next(); 468 p->set_next(NULL); 469 Symbol* class_name = p->klass()->name(); 470 // Since the null class loader data isn't copied to the CDS archive, 471 // compute the hash with NULL for loader data. 472 unsigned int hash = compute_hash(class_name, NULL); 473 int index = hash_to_index(hash); 474 p->set_hash(hash); 475 p->set_loader_data(NULL); // loader_data isn't copied to CDS 476 p->set_next(bucket(index)); 477 set_entry(index, p); 478 } 479 } 480 481 482 unsigned int ProtectionDomainCacheTable::compute_hash(Handle protection_domain) { 483 // Identity hash can safepoint, so keep protection domain in a Handle. 484 return (unsigned int)(protection_domain->identity_hash()); 485 } 486 487 int ProtectionDomainCacheTable::index_for(Handle protection_domain) { 488 return hash_to_index(compute_hash(protection_domain)); 489 } 490 491 ProtectionDomainCacheTable::ProtectionDomainCacheTable(int table_size) 492 : Hashtable<oop, mtClass>(table_size, sizeof(ProtectionDomainCacheEntry)) 493 { 494 } 495 496 void ProtectionDomainCacheTable::unlink(BoolObjectClosure* is_alive) { 497 assert(SafepointSynchronize::is_at_safepoint(), "must be"); 498 for (int i = 0; i < table_size(); ++i) { 499 ProtectionDomainCacheEntry** p = bucket_addr(i); 500 ProtectionDomainCacheEntry* entry = bucket(i); 501 while (entry != NULL) { 502 if (is_alive->do_object_b(entry->literal())) { 503 p = entry->next_addr(); 504 } else { 505 *p = entry->next(); 506 free_entry(entry); 507 } 508 entry = *p; 509 } 510 } 511 } 512 513 void ProtectionDomainCacheTable::oops_do(OopClosure* f) { 514 for (int index = 0; index < table_size(); index++) { 515 for (ProtectionDomainCacheEntry* probe = bucket(index); 516 probe != NULL; 517 probe = probe->next()) { 518 probe->oops_do(f); 519 } 520 } 521 } 522 523 524 uint ProtectionDomainCacheTable::bucket_size() { 525 return sizeof(ProtectionDomainCacheEntry); 526 } 527 528 #ifndef PRODUCT 529 void ProtectionDomainCacheTable::print() { 530 tty->print_cr("Protection domain cache table (table_size=%d, classes=%d)", 531 table_size(), number_of_entries()); 532 for (int index = 0; index < table_size(); index++) { 533 for (ProtectionDomainCacheEntry* probe = bucket(index); 534 probe != NULL; 535 probe = probe->next()) { 536 probe->print(); 537 } 538 } 539 } 540 541 void ProtectionDomainCacheEntry::print() { 542 tty->print_cr("entry " PTR_FORMAT " value " PTR_FORMAT " next " PTR_FORMAT, 543 p2i(this), p2i(literal()), p2i(next())); 544 } 545 #endif 546 547 void ProtectionDomainCacheTable::verify() { 548 int element_count = 0; 549 for (int index = 0; index < table_size(); index++) { 550 for (ProtectionDomainCacheEntry* probe = bucket(index); 551 probe != NULL; 552 probe = probe->next()) { 553 probe->verify(); 554 element_count++; 555 } 556 } 557 guarantee(number_of_entries() == element_count, 558 "Verify of protection domain cache table failed"); 559 DEBUG_ONLY(verify_lookup_length((double)number_of_entries() / table_size(), "Domain Cache Table")); 560 } 561 562 void ProtectionDomainCacheEntry::verify() { 563 guarantee(literal()->is_oop(), "must be an oop"); 564 } 565 566 ProtectionDomainCacheEntry* ProtectionDomainCacheTable::get(Handle protection_domain) { 567 unsigned int hash = compute_hash(protection_domain); 568 int index = hash_to_index(hash); 569 570 ProtectionDomainCacheEntry* entry = find_entry(index, protection_domain); 571 if (entry == NULL) { 572 entry = add_entry(index, hash, protection_domain); 573 } 574 return entry; 575 } 576 577 ProtectionDomainCacheEntry* ProtectionDomainCacheTable::find_entry(int index, Handle protection_domain) { 578 for (ProtectionDomainCacheEntry* e = bucket(index); e != NULL; e = e->next()) { 579 if (e->protection_domain() == protection_domain()) { 580 return e; 581 } 582 } 583 584 return NULL; 585 } 586 587 ProtectionDomainCacheEntry* ProtectionDomainCacheTable::add_entry(int index, unsigned int hash, Handle protection_domain) { 588 assert_locked_or_safepoint(SystemDictionary_lock); 589 assert(index == index_for(protection_domain), "incorrect index?"); 590 assert(find_entry(index, protection_domain) == NULL, "no double entry"); 591 592 ProtectionDomainCacheEntry* p = new_entry(hash, protection_domain); 593 Hashtable<oop, mtClass>::add_entry(index, p); 594 return p; 595 } 596 597 void ProtectionDomainCacheTable::free(ProtectionDomainCacheEntry* to_delete) { 598 unsigned int hash = compute_hash(Handle(Thread::current(), to_delete->protection_domain())); 599 int index = hash_to_index(hash); 600 601 ProtectionDomainCacheEntry** p = bucket_addr(index); 602 ProtectionDomainCacheEntry* entry = bucket(index); 603 while (true) { 604 assert(entry != NULL, "sanity"); 605 606 if (entry == to_delete) { 607 *p = entry->next(); 608 Hashtable<oop, mtClass>::free_entry(entry); 609 break; 610 } else { 611 p = entry->next_addr(); 612 entry = *p; 613 } 614 } 615 } 616 617 SymbolPropertyTable::SymbolPropertyTable(int table_size) 618 : Hashtable<Symbol*, mtSymbol>(table_size, sizeof(SymbolPropertyEntry)) 619 { 620 } 621 SymbolPropertyTable::SymbolPropertyTable(int table_size, HashtableBucket<mtSymbol>* t, 622 int number_of_entries) 623 : Hashtable<Symbol*, mtSymbol>(table_size, sizeof(SymbolPropertyEntry), t, number_of_entries) 624 { 625 } 626 627 628 SymbolPropertyEntry* SymbolPropertyTable::find_entry(int index, unsigned int hash, 629 Symbol* sym, 630 intptr_t sym_mode) { 631 assert(index == index_for(sym, sym_mode), "incorrect index?"); 632 for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) { 633 if (p->hash() == hash && p->symbol() == sym && p->symbol_mode() == sym_mode) { 634 return p; 635 } 636 } 637 return NULL; 638 } 639 640 641 SymbolPropertyEntry* SymbolPropertyTable::add_entry(int index, unsigned int hash, 642 Symbol* sym, intptr_t sym_mode) { 643 assert_locked_or_safepoint(SystemDictionary_lock); 644 assert(index == index_for(sym, sym_mode), "incorrect index?"); 645 assert(find_entry(index, hash, sym, sym_mode) == NULL, "no double entry"); 646 647 SymbolPropertyEntry* p = new_entry(hash, sym, sym_mode); 648 Hashtable<Symbol*, mtSymbol>::add_entry(index, p); 649 return p; 650 } 651 652 void SymbolPropertyTable::oops_do(OopClosure* f) { 653 for (int index = 0; index < table_size(); index++) { 654 for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) { 655 if (p->method_type() != NULL) { 656 f->do_oop(p->method_type_addr()); 657 } 658 } 659 } 660 } 661 662 void SymbolPropertyTable::methods_do(void f(Method*)) { 663 for (int index = 0; index < table_size(); index++) { 664 for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) { 665 Method* prop = p->method(); 666 if (prop != NULL) { 667 f((Method*)prop); 668 } 669 } 670 } 671 } 672 673 674 // ---------------------------------------------------------------------------- 675 676 void Dictionary::print(bool details) { 677 ResourceMark rm; 678 679 if (details) { 680 tty->print_cr("Java system dictionary (table_size=%d, classes=%d)", 681 table_size(), number_of_entries()); 682 tty->print_cr("^ indicates that initiating loader is different from " 683 "defining loader"); 684 } 685 686 for (int index = 0; index < table_size(); index++) { 687 for (DictionaryEntry* probe = bucket(index); 688 probe != NULL; 689 probe = probe->next()) { 690 Klass* e = probe->klass(); 691 ClassLoaderData* loader_data = probe->loader_data(); 692 bool is_defining_class = 693 (loader_data == e->class_loader_data()); 694 if (details) { 695 tty->print("%4d: ", index); 696 } 697 tty->print("%s%s", ((!details) || is_defining_class) ? " " : "^", 698 e->external_name()); 699 700 if (details) { 701 tty->print(", loader "); 702 if (loader_data != NULL) { 703 loader_data->print_value(); 704 } else { 705 tty->print("NULL"); 706 } 707 } 708 tty->cr(); 709 } 710 } 711 712 if (details) { 713 tty->cr(); 714 _pd_cache_table->print(); 715 } 716 tty->cr(); 717 } 718 719 #ifdef ASSERT 720 void Dictionary::printPerformanceInfoDetails() { 721 if (log_is_enabled(Info, hashtables)) { 722 ResourceMark rm; 723 724 log_info(hashtables)(" "); 725 log_info(hashtables)("Java system dictionary (table_size=%d, classes=%d)", 726 table_size(), number_of_entries()); 727 log_info(hashtables)("1st number: the bucket index"); 728 log_info(hashtables)("2nd number: the hit percentage for this bucket"); 729 log_info(hashtables)("3rd number: the entry's index within this bucket"); 730 log_info(hashtables)("4th number: the hash index of this entry"); 731 log_info(hashtables)(" "); 732 733 // find top buckets with highest lookup count 734 #define TOP_COUNT 16 735 int topItemsIndicies[TOP_COUNT]; 736 for (int i = 0; i < TOP_COUNT; i++) { 737 topItemsIndicies[i] = i; 738 } 739 double total = 0.0; 740 for (int i = 0; i < table_size(); i++) { 741 // find the total count number, so later on we can 742 // express bucket lookup count as a percentage of all lookups 743 unsigned value = bucket_hits(i); 744 total += value; 745 746 // find the top entry with min value 747 int min_index = 0; 748 unsigned min_value = bucket_hits(topItemsIndicies[min_index]); 749 for (int j = 1; j < TOP_COUNT; j++) { 750 unsigned top_value = bucket_hits(topItemsIndicies[j]); 751 if (top_value < min_value) { 752 min_value = top_value; 753 min_index = j; 754 } 755 } 756 // if the bucket loookup value is bigger than the top buckets min 757 // move that bucket index into the top list 758 if (value > min_value) { 759 topItemsIndicies[min_index] = i; 760 } 761 } 762 763 for (int index = 0; index < table_size(); index++) { 764 double percentage = 100.0 * (double)bucket_hits(index)/total; 765 int chain = 0; 766 for (DictionaryEntry* probe = bucket(index); 767 probe != NULL; 768 probe = probe->next()) { 769 Klass* e = probe->klass(); 770 ClassLoaderData* loader_data = probe->loader_data(); 771 bool is_defining_class = 772 (loader_data == e->class_loader_data()); 773 log_info(hashtables)("%4d: %5.2f%%: %3d: %10u: %s, loader %s", 774 index, percentage, chain, probe->hash(), e->external_name(), 775 (loader_data != NULL) ? loader_data->loader_name() : "NULL"); 776 777 chain++; 778 } 779 if (chain == 0) { 780 log_info(hashtables)("%4d:", index+1); 781 } 782 } 783 log_info(hashtables)(" "); 784 785 // print out the TOP_COUNT of buckets with highest lookup count (unsorted) 786 log_info(hashtables)("Top %d buckets:", TOP_COUNT); 787 for (int i = 0; i < TOP_COUNT; i++) { 788 log_info(hashtables)("%4d: hits %5.2f%%", 789 topItemsIndicies[i], 790 100.0*(double)bucket_hits(topItemsIndicies[i])/total); 791 } 792 } 793 } 794 #endif // ASSERT 795 796 void Dictionary::verify() { 797 guarantee(number_of_entries() >= 0, "Verify of system dictionary failed"); 798 799 int element_count = 0; 800 for (int index = 0; index < table_size(); index++) { 801 for (DictionaryEntry* probe = bucket(index); 802 probe != NULL; 803 probe = probe->next()) { 804 Klass* e = probe->klass(); 805 ClassLoaderData* loader_data = probe->loader_data(); 806 guarantee(e->is_instance_klass(), 807 "Verify of system dictionary failed"); 808 // class loader must be present; a null class loader is the 809 // boostrap loader 810 guarantee(loader_data != NULL || DumpSharedSpaces || 811 loader_data->class_loader() == NULL || 812 loader_data->class_loader()->is_instance(), 813 "checking type of class_loader"); 814 e->verify(); 815 probe->verify_protection_domain_set(); 816 element_count++; 817 } 818 } 819 guarantee(number_of_entries() == element_count, 820 "Verify of system dictionary failed"); 821 #ifdef ASSERT 822 if (!verify_lookup_length((double)number_of_entries() / table_size(), "System Dictionary")) { 823 this->printPerformanceInfoDetails(); 824 } 825 #endif // ASSERT 826 827 _pd_cache_table->verify(); 828 } 829