Mon, 07 Jul 2014 10:12:40 +0200
8049421: G1 Class Unloading after completing a concurrent mark cycle
Reviewed-by: tschatzl, ehelin, brutisso, coleenp, roland, iveresov
Contributed-by: stefan.karlsson@oracle.com, mikael.gerdin@oracle.com
1 /*
2 * Copyright (c) 2003, 2014, 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 */
25 #include "precompiled.hpp"
26 #include "classfile/dictionary.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "memory/iterator.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "prims/jvmtiRedefineClassesTrace.hpp"
31 #include "runtime/orderAccess.inline.hpp"
32 #include "utilities/hashtable.inline.hpp"
34 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
36 DictionaryEntry* Dictionary::_current_class_entry = NULL;
37 int Dictionary::_current_class_index = 0;
40 Dictionary::Dictionary(int table_size)
41 : TwoOopHashtable<Klass*, mtClass>(table_size, sizeof(DictionaryEntry)) {
42 _current_class_index = 0;
43 _current_class_entry = NULL;
44 _pd_cache_table = new ProtectionDomainCacheTable(defaultProtectionDomainCacheSize);
45 };
48 Dictionary::Dictionary(int table_size, HashtableBucket<mtClass>* t,
49 int number_of_entries)
50 : TwoOopHashtable<Klass*, mtClass>(table_size, sizeof(DictionaryEntry), t, number_of_entries) {
51 _current_class_index = 0;
52 _current_class_entry = NULL;
53 _pd_cache_table = new ProtectionDomainCacheTable(defaultProtectionDomainCacheSize);
54 };
56 ProtectionDomainCacheEntry* Dictionary::cache_get(oop protection_domain) {
57 return _pd_cache_table->get(protection_domain);
58 }
60 DictionaryEntry* Dictionary::new_entry(unsigned int hash, Klass* klass,
61 ClassLoaderData* loader_data) {
62 DictionaryEntry* entry = (DictionaryEntry*)Hashtable<Klass*, mtClass>::new_entry(hash, klass);
63 entry->set_loader_data(loader_data);
64 entry->set_pd_set(NULL);
65 assert(klass->oop_is_instance(), "Must be");
66 return entry;
67 }
70 void Dictionary::free_entry(DictionaryEntry* entry) {
71 // avoid recursion when deleting linked list
72 while (entry->pd_set() != NULL) {
73 ProtectionDomainEntry* to_delete = entry->pd_set();
74 entry->set_pd_set(to_delete->next());
75 delete to_delete;
76 }
77 Hashtable<Klass*, mtClass>::free_entry(entry);
78 }
81 bool DictionaryEntry::contains_protection_domain(oop protection_domain) const {
82 #ifdef ASSERT
83 if (protection_domain == InstanceKlass::cast(klass())->protection_domain()) {
84 // Ensure this doesn't show up in the pd_set (invariant)
85 bool in_pd_set = false;
86 for (ProtectionDomainEntry* current = _pd_set;
87 current != NULL;
88 current = current->next()) {
89 if (current->protection_domain() == protection_domain) {
90 in_pd_set = true;
91 break;
92 }
93 }
94 if (in_pd_set) {
95 assert(false, "A klass's protection domain should not show up "
96 "in its sys. dict. PD set");
97 }
98 }
99 #endif /* ASSERT */
101 if (protection_domain == InstanceKlass::cast(klass())->protection_domain()) {
102 // Succeeds trivially
103 return true;
104 }
106 for (ProtectionDomainEntry* current = _pd_set;
107 current != NULL;
108 current = current->next()) {
109 if (current->protection_domain() == protection_domain) return true;
110 }
111 return false;
112 }
115 void DictionaryEntry::add_protection_domain(Dictionary* dict, oop protection_domain) {
116 assert_locked_or_safepoint(SystemDictionary_lock);
117 if (!contains_protection_domain(protection_domain)) {
118 ProtectionDomainCacheEntry* entry = dict->cache_get(protection_domain);
119 ProtectionDomainEntry* new_head =
120 new ProtectionDomainEntry(entry, _pd_set);
121 // Warning: Preserve store ordering. The SystemDictionary is read
122 // without locks. The new ProtectionDomainEntry must be
123 // complete before other threads can be allowed to see it
124 // via a store to _pd_set.
125 OrderAccess::release_store_ptr(&_pd_set, new_head);
126 }
127 if (TraceProtectionDomainVerification && WizardMode) {
128 print();
129 }
130 }
133 bool Dictionary::do_unloading() {
134 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
135 bool class_was_unloaded = false;
136 int index = 0; // Defined here for portability! Do not move
138 // Remove unloadable entries and classes from system dictionary
139 // The placeholder array has been handled in always_strong_oops_do.
140 DictionaryEntry* probe = NULL;
141 for (index = 0; index < table_size(); index++) {
142 for (DictionaryEntry** p = bucket_addr(index); *p != NULL; ) {
143 probe = *p;
144 Klass* e = probe->klass();
145 ClassLoaderData* loader_data = probe->loader_data();
147 InstanceKlass* ik = InstanceKlass::cast(e);
149 // Non-unloadable classes were handled in always_strong_oops_do
150 if (!is_strongly_reachable(loader_data, e)) {
151 // Entry was not visited in phase1 (negated test from phase1)
152 assert(!loader_data->is_the_null_class_loader_data(), "unloading entry with null class loader");
153 ClassLoaderData* k_def_class_loader_data = ik->class_loader_data();
155 // Do we need to delete this system dictionary entry?
156 bool purge_entry = false;
158 // Do we need to delete this system dictionary entry?
159 if (loader_data->is_unloading()) {
160 // If the loader is not live this entry should always be
161 // removed (will never be looked up again). Note that this is
162 // not the same as unloading the referred class.
163 if (k_def_class_loader_data == loader_data) {
164 // This is the defining entry, so the referred class is about
165 // to be unloaded.
166 class_was_unloaded = true;
167 }
168 // Also remove this system dictionary entry.
169 purge_entry = true;
171 } else {
172 // The loader in this entry is alive. If the klass is dead,
173 // (determined by checking the defining class loader)
174 // the loader must be an initiating loader (rather than the
175 // defining loader). Remove this entry.
176 if (k_def_class_loader_data->is_unloading()) {
177 // If we get here, the class_loader_data must not be the defining
178 // loader, it must be an initiating one.
179 assert(k_def_class_loader_data != loader_data,
180 "cannot have live defining loader and unreachable klass");
181 // Loader is live, but class and its defining loader are dead.
182 // Remove the entry. The class is going away.
183 purge_entry = true;
184 }
185 }
187 if (purge_entry) {
188 *p = probe->next();
189 if (probe == _current_class_entry) {
190 _current_class_entry = NULL;
191 }
192 free_entry(probe);
193 continue;
194 }
195 }
196 p = probe->next_addr();
197 }
198 }
199 return class_was_unloaded;
200 }
202 void Dictionary::roots_oops_do(OopClosure* strong, OopClosure* weak) {
203 // Skip the strong roots probe marking if the closures are the same.
204 if (strong == weak) {
205 oops_do(strong);
206 return;
207 }
209 for (int index = 0; index < table_size(); index++) {
210 for (DictionaryEntry *probe = bucket(index);
211 probe != NULL;
212 probe = probe->next()) {
213 Klass* e = probe->klass();
214 ClassLoaderData* loader_data = probe->loader_data();
215 if (is_strongly_reachable(loader_data, e)) {
216 probe->set_strongly_reachable();
217 }
218 }
219 }
220 _pd_cache_table->roots_oops_do(strong, weak);
221 }
223 void Dictionary::always_strong_oops_do(OopClosure* blk) {
224 // Follow all system classes and temporary placeholders in dictionary; only
225 // protection domain oops contain references into the heap. In a first
226 // pass over the system dictionary determine which need to be treated as
227 // strongly reachable and mark them as such.
228 for (int index = 0; index < table_size(); index++) {
229 for (DictionaryEntry *probe = bucket(index);
230 probe != NULL;
231 probe = probe->next()) {
232 Klass* e = probe->klass();
233 ClassLoaderData* loader_data = probe->loader_data();
234 if (is_strongly_reachable(loader_data, e)) {
235 probe->set_strongly_reachable();
236 }
237 }
238 }
239 // Then iterate over the protection domain cache to apply the closure on the
240 // previously marked ones.
241 _pd_cache_table->always_strong_oops_do(blk);
242 }
245 void Dictionary::always_strong_classes_do(KlassClosure* closure) {
246 // Follow all system classes and temporary placeholders in dictionary
247 for (int index = 0; index < table_size(); index++) {
248 for (DictionaryEntry* probe = bucket(index);
249 probe != NULL;
250 probe = probe->next()) {
251 Klass* e = probe->klass();
252 ClassLoaderData* loader_data = probe->loader_data();
253 if (is_strongly_reachable(loader_data, e)) {
254 closure->do_klass(e);
255 }
256 }
257 }
258 }
261 // Just the classes from defining class loaders
262 void Dictionary::classes_do(void f(Klass*)) {
263 for (int index = 0; index < table_size(); index++) {
264 for (DictionaryEntry* probe = bucket(index);
265 probe != NULL;
266 probe = probe->next()) {
267 Klass* k = probe->klass();
268 if (probe->loader_data() == InstanceKlass::cast(k)->class_loader_data()) {
269 f(k);
270 }
271 }
272 }
273 }
275 // Added for initialize_itable_for_klass to handle exceptions
276 // Just the classes from defining class loaders
277 void Dictionary::classes_do(void f(Klass*, TRAPS), TRAPS) {
278 for (int index = 0; index < table_size(); index++) {
279 for (DictionaryEntry* probe = bucket(index);
280 probe != NULL;
281 probe = probe->next()) {
282 Klass* k = probe->klass();
283 if (probe->loader_data() == InstanceKlass::cast(k)->class_loader_data()) {
284 f(k, CHECK);
285 }
286 }
287 }
288 }
290 // All classes, and their class loaders
291 // Don't iterate over placeholders
292 void Dictionary::classes_do(void f(Klass*, ClassLoaderData*)) {
293 for (int index = 0; index < table_size(); index++) {
294 for (DictionaryEntry* probe = bucket(index);
295 probe != NULL;
296 probe = probe->next()) {
297 Klass* k = probe->klass();
298 f(k, probe->loader_data());
299 }
300 }
301 }
303 void Dictionary::oops_do(OopClosure* f) {
304 // Only the protection domain oops contain references into the heap. Iterate
305 // over all of them.
306 _pd_cache_table->oops_do(f);
307 }
309 void Dictionary::methods_do(void f(Method*)) {
310 for (int index = 0; index < table_size(); index++) {
311 for (DictionaryEntry* probe = bucket(index);
312 probe != NULL;
313 probe = probe->next()) {
314 Klass* k = probe->klass();
315 if (probe->loader_data() == InstanceKlass::cast(k)->class_loader_data()) {
316 // only take klass is we have the entry with the defining class loader
317 InstanceKlass::cast(k)->methods_do(f);
318 }
319 }
320 }
321 }
323 void Dictionary::unlink(BoolObjectClosure* is_alive) {
324 // Only the protection domain cache table may contain references to the heap
325 // that need to be unlinked.
326 _pd_cache_table->unlink(is_alive);
327 }
329 Klass* Dictionary::try_get_next_class() {
330 while (true) {
331 if (_current_class_entry != NULL) {
332 Klass* k = _current_class_entry->klass();
333 _current_class_entry = _current_class_entry->next();
334 return k;
335 }
336 _current_class_index = (_current_class_index + 1) % table_size();
337 _current_class_entry = bucket(_current_class_index);
338 }
339 // never reached
340 }
342 // Add a loaded class to the system dictionary.
343 // Readers of the SystemDictionary aren't always locked, so _buckets
344 // is volatile. The store of the next field in the constructor is
345 // also cast to volatile; we do this to ensure store order is maintained
346 // by the compilers.
348 void Dictionary::add_klass(Symbol* class_name, ClassLoaderData* loader_data,
349 KlassHandle obj) {
350 assert_locked_or_safepoint(SystemDictionary_lock);
351 assert(obj() != NULL, "adding NULL obj");
352 assert(obj()->name() == class_name, "sanity check on name");
353 assert(loader_data != NULL, "Must be non-NULL");
355 unsigned int hash = compute_hash(class_name, loader_data);
356 int index = hash_to_index(hash);
357 DictionaryEntry* entry = new_entry(hash, obj(), loader_data);
358 add_entry(index, entry);
359 }
362 // This routine does not lock the system dictionary.
363 //
364 // Since readers don't hold a lock, we must make sure that system
365 // dictionary entries are only removed at a safepoint (when only one
366 // thread is running), and are added to in a safe way (all links must
367 // be updated in an MT-safe manner).
368 //
369 // Callers should be aware that an entry could be added just after
370 // _buckets[index] is read here, so the caller will not see the new entry.
371 DictionaryEntry* Dictionary::get_entry(int index, unsigned int hash,
372 Symbol* class_name,
373 ClassLoaderData* loader_data) {
374 debug_only(_lookup_count++);
375 for (DictionaryEntry* entry = bucket(index);
376 entry != NULL;
377 entry = entry->next()) {
378 if (entry->hash() == hash && entry->equals(class_name, loader_data)) {
379 return entry;
380 }
381 debug_only(_lookup_length++);
382 }
383 return NULL;
384 }
387 Klass* 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 }
398 Klass* 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?");
403 DictionaryEntry* entry = get_entry(index, hash, name, loader_data);
404 return (entry != NULL) ? entry->klass() : (Klass*)NULL;
405 }
408 // Variant of find_class for shared classes. No locking required, as
409 // that table is static.
411 Klass* Dictionary::find_shared_class(int index, unsigned int hash,
412 Symbol* name) {
413 assert (index == index_for(name, NULL), "incorrect index?");
415 DictionaryEntry* entry = get_entry(index, hash, name, NULL);
416 return (entry != NULL) ? entry->klass() : (Klass*)NULL;
417 }
420 void Dictionary::add_protection_domain(int index, unsigned int hash,
421 instanceKlassHandle 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);
427 assert(entry != NULL,"entry must be present, we just created it");
428 assert(protection_domain() != NULL,
429 "real protection domain should be present");
431 entry->add_protection_domain(this, protection_domain());
433 assert(entry->contains_protection_domain(protection_domain()),
434 "now protection domain should be present");
435 }
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 }
447 void Dictionary::reorder_dictionary() {
449 // Copy all the dictionary entries into a single master list.
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 }
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 = InstanceKlass::cast((Klass*)(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 }
481 ProtectionDomainCacheTable::ProtectionDomainCacheTable(int table_size)
482 : Hashtable<oop, mtClass>(table_size, sizeof(ProtectionDomainCacheEntry))
483 {
484 }
486 void ProtectionDomainCacheTable::unlink(BoolObjectClosure* is_alive) {
487 assert(SafepointSynchronize::is_at_safepoint(), "must be");
488 for (int i = 0; i < table_size(); ++i) {
489 ProtectionDomainCacheEntry** p = bucket_addr(i);
490 ProtectionDomainCacheEntry* entry = bucket(i);
491 while (entry != NULL) {
492 if (is_alive->do_object_b(entry->literal())) {
493 p = entry->next_addr();
494 } else {
495 *p = entry->next();
496 free_entry(entry);
497 }
498 entry = *p;
499 }
500 }
501 }
503 void ProtectionDomainCacheTable::oops_do(OopClosure* f) {
504 for (int index = 0; index < table_size(); index++) {
505 for (ProtectionDomainCacheEntry* probe = bucket(index);
506 probe != NULL;
507 probe = probe->next()) {
508 probe->oops_do(f);
509 }
510 }
511 }
513 void ProtectionDomainCacheTable::roots_oops_do(OopClosure* strong, OopClosure* weak) {
514 for (int index = 0; index < table_size(); index++) {
515 for (ProtectionDomainCacheEntry* probe = bucket(index);
516 probe != NULL;
517 probe = probe->next()) {
518 if (probe->is_strongly_reachable()) {
519 probe->reset_strongly_reachable();
520 probe->oops_do(strong);
521 } else {
522 if (weak != NULL) {
523 probe->oops_do(weak);
524 }
525 }
526 }
527 }
528 }
530 uint ProtectionDomainCacheTable::bucket_size() {
531 return sizeof(ProtectionDomainCacheEntry);
532 }
534 #ifndef PRODUCT
535 void ProtectionDomainCacheTable::print() {
536 tty->print_cr("Protection domain cache table (table_size=%d, classes=%d)",
537 table_size(), number_of_entries());
538 for (int index = 0; index < table_size(); index++) {
539 for (ProtectionDomainCacheEntry* probe = bucket(index);
540 probe != NULL;
541 probe = probe->next()) {
542 probe->print();
543 }
544 }
545 }
547 void ProtectionDomainCacheEntry::print() {
548 tty->print_cr("entry "PTR_FORMAT" value "PTR_FORMAT" strongly_reachable %d next "PTR_FORMAT,
549 this, (void*)literal(), _strongly_reachable, next());
550 }
551 #endif
553 void ProtectionDomainCacheTable::verify() {
554 int element_count = 0;
555 for (int index = 0; index < table_size(); index++) {
556 for (ProtectionDomainCacheEntry* probe = bucket(index);
557 probe != NULL;
558 probe = probe->next()) {
559 probe->verify();
560 element_count++;
561 }
562 }
563 guarantee(number_of_entries() == element_count,
564 "Verify of protection domain cache table failed");
565 debug_only(verify_lookup_length((double)number_of_entries() / table_size()));
566 }
568 void ProtectionDomainCacheEntry::verify() {
569 guarantee(literal()->is_oop(), "must be an oop");
570 }
572 void ProtectionDomainCacheTable::always_strong_oops_do(OopClosure* f) {
573 // the caller marked the protection domain cache entries that we need to apply
574 // the closure on. Only process them.
575 for (int index = 0; index < table_size(); index++) {
576 for (ProtectionDomainCacheEntry* probe = bucket(index);
577 probe != NULL;
578 probe = probe->next()) {
579 if (probe->is_strongly_reachable()) {
580 probe->reset_strongly_reachable();
581 probe->oops_do(f);
582 }
583 }
584 }
585 }
587 ProtectionDomainCacheEntry* ProtectionDomainCacheTable::get(oop protection_domain) {
588 unsigned int hash = compute_hash(protection_domain);
589 int index = hash_to_index(hash);
591 ProtectionDomainCacheEntry* entry = find_entry(index, protection_domain);
592 if (entry == NULL) {
593 entry = add_entry(index, hash, protection_domain);
594 }
595 return entry;
596 }
598 ProtectionDomainCacheEntry* ProtectionDomainCacheTable::find_entry(int index, oop protection_domain) {
599 for (ProtectionDomainCacheEntry* e = bucket(index); e != NULL; e = e->next()) {
600 if (e->protection_domain() == protection_domain) {
601 return e;
602 }
603 }
605 return NULL;
606 }
608 ProtectionDomainCacheEntry* ProtectionDomainCacheTable::add_entry(int index, unsigned int hash, oop protection_domain) {
609 assert_locked_or_safepoint(SystemDictionary_lock);
610 assert(index == index_for(protection_domain), "incorrect index?");
611 assert(find_entry(index, protection_domain) == NULL, "no double entry");
613 ProtectionDomainCacheEntry* p = new_entry(hash, protection_domain);
614 Hashtable<oop, mtClass>::add_entry(index, p);
615 return p;
616 }
618 void ProtectionDomainCacheTable::free(ProtectionDomainCacheEntry* to_delete) {
619 unsigned int hash = compute_hash(to_delete->protection_domain());
620 int index = hash_to_index(hash);
622 ProtectionDomainCacheEntry** p = bucket_addr(index);
623 ProtectionDomainCacheEntry* entry = bucket(index);
624 while (true) {
625 assert(entry != NULL, "sanity");
627 if (entry == to_delete) {
628 *p = entry->next();
629 Hashtable<oop, mtClass>::free_entry(entry);
630 break;
631 } else {
632 p = entry->next_addr();
633 entry = *p;
634 }
635 }
636 }
638 SymbolPropertyTable::SymbolPropertyTable(int table_size)
639 : Hashtable<Symbol*, mtSymbol>(table_size, sizeof(SymbolPropertyEntry))
640 {
641 }
642 SymbolPropertyTable::SymbolPropertyTable(int table_size, HashtableBucket<mtSymbol>* t,
643 int number_of_entries)
644 : Hashtable<Symbol*, mtSymbol>(table_size, sizeof(SymbolPropertyEntry), t, number_of_entries)
645 {
646 }
649 SymbolPropertyEntry* SymbolPropertyTable::find_entry(int index, unsigned int hash,
650 Symbol* sym,
651 intptr_t sym_mode) {
652 assert(index == index_for(sym, sym_mode), "incorrect index?");
653 for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) {
654 if (p->hash() == hash && p->symbol() == sym && p->symbol_mode() == sym_mode) {
655 return p;
656 }
657 }
658 return NULL;
659 }
662 SymbolPropertyEntry* SymbolPropertyTable::add_entry(int index, unsigned int hash,
663 Symbol* sym, intptr_t sym_mode) {
664 assert_locked_or_safepoint(SystemDictionary_lock);
665 assert(index == index_for(sym, sym_mode), "incorrect index?");
666 assert(find_entry(index, hash, sym, sym_mode) == NULL, "no double entry");
668 SymbolPropertyEntry* p = new_entry(hash, sym, sym_mode);
669 Hashtable<Symbol*, mtSymbol>::add_entry(index, p);
670 return p;
671 }
673 void SymbolPropertyTable::oops_do(OopClosure* f) {
674 for (int index = 0; index < table_size(); index++) {
675 for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) {
676 if (p->method_type() != NULL) {
677 f->do_oop(p->method_type_addr());
678 }
679 }
680 }
681 }
683 void SymbolPropertyTable::methods_do(void f(Method*)) {
684 for (int index = 0; index < table_size(); index++) {
685 for (SymbolPropertyEntry* p = bucket(index); p != NULL; p = p->next()) {
686 Method* prop = p->method();
687 if (prop != NULL) {
688 f((Method*)prop);
689 }
690 }
691 }
692 }
695 // ----------------------------------------------------------------------------
696 #ifndef PRODUCT
698 void Dictionary::print() {
699 ResourceMark rm;
700 HandleMark hm;
702 tty->print_cr("Java system dictionary (table_size=%d, classes=%d)",
703 table_size(), number_of_entries());
704 tty->print_cr("^ indicates that initiating loader is different from "
705 "defining loader");
707 for (int index = 0; index < table_size(); index++) {
708 for (DictionaryEntry* probe = bucket(index);
709 probe != NULL;
710 probe = probe->next()) {
711 if (Verbose) tty->print("%4d: ", index);
712 Klass* e = probe->klass();
713 ClassLoaderData* loader_data = probe->loader_data();
714 bool is_defining_class =
715 (loader_data == InstanceKlass::cast(e)->class_loader_data());
716 tty->print("%s%s", is_defining_class ? " " : "^",
717 e->external_name());
719 tty->print(", loader ");
720 loader_data->print_value();
721 tty->cr();
722 }
723 }
724 tty->cr();
725 _pd_cache_table->print();
726 tty->cr();
727 }
729 #endif
731 void Dictionary::verify() {
732 guarantee(number_of_entries() >= 0, "Verify of system dictionary failed");
734 int element_count = 0;
735 for (int index = 0; index < table_size(); index++) {
736 for (DictionaryEntry* probe = bucket(index);
737 probe != NULL;
738 probe = probe->next()) {
739 Klass* e = probe->klass();
740 ClassLoaderData* loader_data = probe->loader_data();
741 guarantee(e->oop_is_instance(),
742 "Verify of system dictionary failed");
743 // class loader must be present; a null class loader is the
744 // boostrap loader
745 guarantee(loader_data != NULL || DumpSharedSpaces ||
746 loader_data->class_loader() == NULL ||
747 loader_data->class_loader()->is_instance(),
748 "checking type of class_loader");
749 e->verify();
750 probe->verify_protection_domain_set();
751 element_count++;
752 }
753 }
754 guarantee(number_of_entries() == element_count,
755 "Verify of system dictionary failed");
756 debug_only(verify_lookup_length((double)number_of_entries() / table_size()));
758 _pd_cache_table->verify();
759 }