1 /*
2 * Copyright (c) 2012, 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 // A ClassLoaderData identifies the full set of class types that a class
26 // loader's name resolution strategy produces for a given configuration of the
27 // class loader.
28 // Class types in the ClassLoaderData may be defined by from class file binaries
29 // provided by the class loader, or from other class loader it interacts with
30 // according to its name resolution strategy.
31 //
32 // Class loaders that implement a deterministic name resolution strategy
33 // (including with respect to their delegation behavior), such as the boot, the
34 // platform, and the system loaders of the JDK's built-in class loader
35 // hierarchy, always produce the same linkset for a given configuration.
36 //
37 // ClassLoaderData carries information related to a linkset (e.g.,
38 // metaspace holding its klass definitions).
39 // The System Dictionary and related data structures (e.g., placeholder table,
40 // loader constraints table) as well as the runtime representation of classes
41 // only reference ClassLoaderData.
42 //
43 // Instances of java.lang.ClassLoader holds a pointer to a ClassLoaderData that
44 // that represent the loader's "linking domain" in the JVM.
45 //
46 // The bootstrap loader (represented by NULL) also has a ClassLoaderData,
47 // the singleton class the_null_class_loader_data().
48
49 #include "precompiled.hpp"
50 #include "classfile/classLoaderData.hpp"
51 #include "classfile/classLoaderData.inline.hpp"
52 #include "classfile/javaClasses.hpp"
53 #include "classfile/metadataOnStackMark.hpp"
54 #include "classfile/moduleEntry.hpp"
55 #include "classfile/packageEntry.hpp"
56 #include "classfile/systemDictionary.hpp"
57 #include "code/codeCache.hpp"
58 #include "gc/shared/gcLocker.hpp"
59 #include "logging/log.hpp"
60 #include "memory/metadataFactory.hpp"
61 #include "memory/metaspaceShared.hpp"
62 #include "memory/oopFactory.hpp"
63 #include "memory/resourceArea.hpp"
64 #include "oops/objArrayOop.inline.hpp"
65 #include "oops/oop.inline.hpp"
66 #include "runtime/atomic.hpp"
67 #include "runtime/javaCalls.hpp"
68 #include "runtime/jniHandles.hpp"
69 #include "runtime/mutex.hpp"
70 #include "runtime/orderAccess.hpp"
71 #include "runtime/safepoint.hpp"
72 #include "runtime/synchronizer.hpp"
73 #include "utilities/growableArray.hpp"
74 #include "utilities/macros.hpp"
75 #include "utilities/ostream.hpp"
76 #if INCLUDE_TRACE
77 #include "trace/tracing.hpp"
78 #endif
79
80 // helper function to avoid in-line casts
81 template <typename T> static T* load_ptr_acquire(T* volatile *p) {
82 return static_cast<T*>(OrderAccess::load_ptr_acquire(p));
83 }
84
85 ClassLoaderData * ClassLoaderData::_the_null_class_loader_data = NULL;
86
87 ClassLoaderData::ClassLoaderData(Handle h_class_loader, bool is_anonymous, Dependencies dependencies) :
88 _class_loader(h_class_loader()),
89 _is_anonymous(is_anonymous),
90 // An anonymous class loader data doesn't have anything to keep
91 // it from being unloaded during parsing of the anonymous class.
92 // The null-class-loader should always be kept alive.
93 _keep_alive((is_anonymous || h_class_loader.is_null()) ? 1 : 0),
94 _metaspace(NULL), _unloading(false), _klasses(NULL),
95 _modules(NULL), _packages(NULL),
96 _claimed(0), _jmethod_ids(NULL), _handles(), _deallocate_list(NULL),
97 _next(NULL), _dependencies(dependencies),
98 _metaspace_lock(new Mutex(Monitor::leaf+1, "Metaspace allocation lock", true,
99 Monitor::_safepoint_check_never)) {
100
101 // A ClassLoaderData created solely for an anonymous class should never have a
102 // ModuleEntryTable or PackageEntryTable created for it. The defining package
103 // and module for an anonymous class will be found in its host class.
104 if (!is_anonymous) {
105 _packages = new PackageEntryTable(PackageEntryTable::_packagetable_entry_size);
106 if (h_class_loader.is_null()) {
107 // Create unnamed module for boot loader
108 _unnamed_module = ModuleEntry::create_boot_unnamed_module(this);
109 } else {
110 // Create unnamed module for all other loaders
111 _unnamed_module = ModuleEntry::create_unnamed_module(this);
112 }
113 } else {
114 _unnamed_module = NULL;
115 }
116 TRACE_INIT_ID(this);
117 }
118
119 void ClassLoaderData::init_dependencies(TRAPS) {
120 assert(!Universe::is_fully_initialized(), "should only be called when initializing");
121 assert(is_the_null_class_loader_data(), "should only call this for the null class loader");
122 _dependencies.init(CHECK);
123 }
124
125 void ClassLoaderData::Dependencies::init(TRAPS) {
126 // Create empty dependencies array to add to. CMS requires this to be
127 // an oop so that it can track additions via card marks. We think.
128 _list_head = oopFactory::new_objectArray(2, CHECK);
129 }
130
131 ClassLoaderData::ChunkedHandleList::~ChunkedHandleList() {
132 Chunk* c = _head;
133 while (c != NULL) {
134 Chunk* next = c->_next;
135 delete c;
136 c = next;
137 }
138 }
139
140 oop* ClassLoaderData::ChunkedHandleList::add(oop o) {
141 if (_head == NULL || _head->_size == Chunk::CAPACITY) {
142 Chunk* next = new Chunk(_head);
143 OrderAccess::release_store_ptr(&_head, next);
144 }
145 oop* handle = &_head->_data[_head->_size];
146 *handle = o;
147 OrderAccess::release_store(&_head->_size, _head->_size + 1);
148 return handle;
149 }
150
151 inline void ClassLoaderData::ChunkedHandleList::oops_do_chunk(OopClosure* f, Chunk* c, const juint size) {
152 for (juint i = 0; i < size; i++) {
153 if (c->_data[i] != NULL) {
154 f->do_oop(&c->_data[i]);
155 }
156 }
157 }
158
159 void ClassLoaderData::ChunkedHandleList::oops_do(OopClosure* f) {
160 Chunk* head = (Chunk*) OrderAccess::load_ptr_acquire(&_head);
161 if (head != NULL) {
162 // Must be careful when reading size of head
163 oops_do_chunk(f, head, OrderAccess::load_acquire(&head->_size));
164 for (Chunk* c = head->_next; c != NULL; c = c->_next) {
165 oops_do_chunk(f, c, c->_size);
166 }
167 }
168 }
169
170 #ifdef ASSERT
171 class VerifyContainsOopClosure : public OopClosure {
172 oop* _target;
173 bool _found;
174
175 public:
176 VerifyContainsOopClosure(oop* target) : _target(target), _found(false) {}
177
178 void do_oop(oop* p) {
179 if (p == _target) {
180 _found = true;
181 }
182 }
183
184 void do_oop(narrowOop* p) {
185 // The ChunkedHandleList should not contain any narrowOop
186 ShouldNotReachHere();
187 }
188
189 bool found() const {
190 return _found;
191 }
192 };
193
194 bool ClassLoaderData::ChunkedHandleList::contains(oop* p) {
195 VerifyContainsOopClosure cl(p);
196 oops_do(&cl);
197 return cl.found();
198 }
199 #endif
200
201 bool ClassLoaderData::claim() {
202 if (_claimed == 1) {
203 return false;
204 }
205
206 return (int) Atomic::cmpxchg(1, &_claimed, 0) == 0;
207 }
208
209 // Anonymous classes have their own ClassLoaderData that is marked to keep alive
210 // while the class is being parsed, and if the class appears on the module fixup list.
211 // Due to the uniqueness that no other class shares the anonymous class' name or
212 // ClassLoaderData, no other non-GC thread has knowledge of the anonymous class while
213 // it is being defined, therefore _keep_alive is not volatile or atomic.
214 void ClassLoaderData::inc_keep_alive() {
215 if (is_anonymous()) {
216 assert(_keep_alive >= 0, "Invalid keep alive increment count");
217 _keep_alive++;
218 }
219 }
220
221 void ClassLoaderData::dec_keep_alive() {
222 if (is_anonymous()) {
223 assert(_keep_alive > 0, "Invalid keep alive decrement count");
224 _keep_alive--;
225 }
226 }
227
228 void ClassLoaderData::oops_do(OopClosure* f, KlassClosure* klass_closure, bool must_claim) {
229 if (must_claim && !claim()) {
230 return;
231 }
232
233 f->do_oop(&_class_loader);
234 _dependencies.oops_do(f);
235
236 _handles.oops_do(f);
237
238 if (klass_closure != NULL) {
239 classes_do(klass_closure);
240 }
241 }
242
243 void ClassLoaderData::Dependencies::oops_do(OopClosure* f) {
244 f->do_oop((oop*)&_list_head);
245 }
246
247 void ClassLoaderData::classes_do(KlassClosure* klass_closure) {
248 // Lock-free access requires load_ptr_acquire
249 for (Klass* k = load_ptr_acquire(&_klasses); k != NULL; k = k->next_link()) {
250 klass_closure->do_klass(k);
251 assert(k != k->next_link(), "no loops!");
252 }
253 }
254
255 void ClassLoaderData::classes_do(void f(Klass * const)) {
256 // Lock-free access requires load_ptr_acquire
257 for (Klass* k = load_ptr_acquire(&_klasses); k != NULL; k = k->next_link()) {
258 f(k);
259 assert(k != k->next_link(), "no loops!");
260 }
261 }
262
263 void ClassLoaderData::methods_do(void f(Method*)) {
264 // Lock-free access requires load_ptr_acquire
265 for (Klass* k = load_ptr_acquire(&_klasses); k != NULL; k = k->next_link()) {
266 if (k->is_instance_klass() && InstanceKlass::cast(k)->is_loaded()) {
267 InstanceKlass::cast(k)->methods_do(f);
268 }
269 }
270 }
271
272 void ClassLoaderData::loaded_classes_do(KlassClosure* klass_closure) {
273 // Lock to avoid classes being modified/added/removed during iteration
274 MutexLockerEx ml(metaspace_lock(), Mutex::_no_safepoint_check_flag);
275 for (Klass* k = _klasses; k != NULL; k = k->next_link()) {
276 // Do not filter ArrayKlass oops here...
277 if (k->is_array_klass() || (k->is_instance_klass() && InstanceKlass::cast(k)->is_loaded())) {
278 klass_closure->do_klass(k);
279 }
280 }
281 }
282
283 void ClassLoaderData::classes_do(void f(InstanceKlass*)) {
284 // Lock-free access requires load_ptr_acquire
285 for (Klass* k = load_ptr_acquire(&_klasses); k != NULL; k = k->next_link()) {
286 if (k->is_instance_klass()) {
287 f(InstanceKlass::cast(k));
288 }
289 assert(k != k->next_link(), "no loops!");
290 }
291 }
292
293 void ClassLoaderData::modules_do(void f(ModuleEntry*)) {
294 assert_locked_or_safepoint(Module_lock);
295 if (_unnamed_module != NULL) {
296 f(_unnamed_module);
297 }
298 if (_modules != NULL) {
299 for (int i = 0; i < _modules->table_size(); i++) {
300 for (ModuleEntry* entry = _modules->bucket(i);
301 entry != NULL;
302 entry = entry->next()) {
303 f(entry);
304 }
305 }
306 }
307 }
308
309 void ClassLoaderData::packages_do(void f(PackageEntry*)) {
310 assert_locked_or_safepoint(Module_lock);
311 if (_packages != NULL) {
312 for (int i = 0; i < _packages->table_size(); i++) {
313 for (PackageEntry* entry = _packages->bucket(i);
314 entry != NULL;
315 entry = entry->next()) {
316 f(entry);
317 }
318 }
319 }
320 }
321
322 void ClassLoaderData::record_dependency(const Klass* k, TRAPS) {
323 assert(k != NULL, "invariant");
324
325 ClassLoaderData * const from_cld = this;
326 ClassLoaderData * const to_cld = k->class_loader_data();
327
328 // Dependency to the null class loader data doesn't need to be recorded
329 // because the null class loader data never goes away.
330 if (to_cld->is_the_null_class_loader_data()) {
331 return;
332 }
333
334 oop to;
335 if (to_cld->is_anonymous()) {
336 // Anonymous class dependencies are through the mirror.
337 to = k->java_mirror();
338 } else {
339 to = to_cld->class_loader();
340
341 // If from_cld is anonymous, even if it's class_loader is a parent of 'to'
342 // we still have to add it. The class_loader won't keep from_cld alive.
343 if (!from_cld->is_anonymous()) {
344 // Check that this dependency isn't from the same or parent class_loader
345 oop from = from_cld->class_loader();
346
347 oop curr = from;
348 while (curr != NULL) {
349 if (curr == to) {
350 return; // this class loader is in the parent list, no need to add it.
351 }
352 curr = java_lang_ClassLoader::parent(curr);
353 }
354 }
355 }
356
357 // It's a dependency we won't find through GC, add it. This is relatively rare
358 // Must handle over GC point.
359 Handle dependency(THREAD, to);
360 from_cld->_dependencies.add(dependency, CHECK);
361 }
362
363
364 void ClassLoaderData::Dependencies::add(Handle dependency, TRAPS) {
365 // Check first if this dependency is already in the list.
366 // Save a pointer to the last to add to under the lock.
367 objArrayOop ok = _list_head;
368 objArrayOop last = NULL;
369 while (ok != NULL) {
370 last = ok;
371 if (ok->obj_at(0) == dependency()) {
372 // Don't need to add it
373 return;
374 }
375 ok = (objArrayOop)ok->obj_at(1);
376 }
377
378 // Must handle over GC points
379 assert (last != NULL, "dependencies should be initialized");
380 objArrayHandle last_handle(THREAD, last);
381
382 // Create a new dependency node with fields for (class_loader or mirror, next)
383 objArrayOop deps = oopFactory::new_objectArray(2, CHECK);
384 deps->obj_at_put(0, dependency());
385
386 // Must handle over GC points
387 objArrayHandle new_dependency(THREAD, deps);
388
389 // Add the dependency under lock
390 locked_add(last_handle, new_dependency, THREAD);
391 }
392
393 void ClassLoaderData::Dependencies::locked_add(objArrayHandle last_handle,
394 objArrayHandle new_dependency,
395 Thread* THREAD) {
396
397 // Have to lock and put the new dependency on the end of the dependency
398 // array so the card mark for CMS sees that this dependency is new.
399 // Can probably do this lock free with some effort.
400 ObjectLocker ol(Handle(THREAD, _list_head), THREAD);
401
402 oop loader_or_mirror = new_dependency->obj_at(0);
403
404 // Since the dependencies are only added, add to the end.
405 objArrayOop end = last_handle();
406 objArrayOop last = NULL;
407 while (end != NULL) {
408 last = end;
409 // check again if another thread added it to the end.
410 if (end->obj_at(0) == loader_or_mirror) {
411 // Don't need to add it
412 return;
413 }
414 end = (objArrayOop)end->obj_at(1);
415 }
416 assert (last != NULL, "dependencies should be initialized");
417 // fill in the first element with the oop in new_dependency.
418 if (last->obj_at(0) == NULL) {
419 last->obj_at_put(0, new_dependency->obj_at(0));
420 } else {
421 last->obj_at_put(1, new_dependency());
422 }
423 }
424
425 void ClassLoaderDataGraph::clear_claimed_marks() {
426 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
427 cld->clear_claimed();
428 }
429 }
430
431 void ClassLoaderData::add_class(Klass* k, bool publicize /* true */) {
432 {
433 MutexLockerEx ml(metaspace_lock(), Mutex::_no_safepoint_check_flag);
434 Klass* old_value = _klasses;
435 k->set_next_link(old_value);
436 // Link the new item into the list, making sure the linked class is stable
437 // since the list can be walked without a lock
438 OrderAccess::release_store_ptr(&_klasses, k);
439 }
440
441 if (publicize && k->class_loader_data() != NULL) {
442 ResourceMark rm;
443 log_trace(class, loader, data)("Adding k: " PTR_FORMAT " %s to CLD: "
444 PTR_FORMAT " loader: " PTR_FORMAT " %s",
445 p2i(k),
446 k->external_name(),
447 p2i(k->class_loader_data()),
448 p2i((void *)k->class_loader()),
449 loader_name());
450 }
451 }
452
453 // Remove a klass from the _klasses list for scratch_class during redefinition
454 // or parsed class in the case of an error.
455 void ClassLoaderData::remove_class(Klass* scratch_class) {
456 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
457 Klass* prev = NULL;
458 for (Klass* k = _klasses; k != NULL; k = k->next_link()) {
459 if (k == scratch_class) {
460 if (prev == NULL) {
461 _klasses = k->next_link();
462 } else {
463 Klass* next = k->next_link();
464 prev->set_next_link(next);
465 }
466 return;
467 }
468 prev = k;
469 assert(k != k->next_link(), "no loops!");
470 }
471 ShouldNotReachHere(); // should have found this class!!
472 }
473
474 void ClassLoaderData::unload() {
475 _unloading = true;
476
477 // Tell serviceability tools these classes are unloading
478 classes_do(InstanceKlass::notify_unload_class);
479
480 if (log_is_enabled(Debug, class, loader, data)) {
481 ResourceMark rm;
482 outputStream* log = Log(class, loader, data)::debug_stream();
483 log->print(": unload loader data " INTPTR_FORMAT, p2i(this));
484 log->print(" for instance " INTPTR_FORMAT " of %s", p2i((void *)class_loader()),
485 loader_name());
486 if (is_anonymous()) {
487 log->print(" for anonymous class " INTPTR_FORMAT " ", p2i(_klasses));
488 }
489 log->cr();
490 }
491
492 // In some rare cases items added to this list will not be freed elsewhere.
493 // To keep it simple, just free everything in it here.
494 free_deallocate_list();
495 }
496
497 ModuleEntryTable* ClassLoaderData::modules() {
498 // Lazily create the module entry table at first request.
499 // Lock-free access requires load_ptr_acquire.
500 ModuleEntryTable* modules = load_ptr_acquire(&_modules);
501 if (modules == NULL) {
502 MutexLocker m1(Module_lock);
503 // Check if _modules got allocated while we were waiting for this lock.
504 if ((modules = _modules) == NULL) {
505 modules = new ModuleEntryTable(ModuleEntryTable::_moduletable_entry_size);
506
507 {
508 MutexLockerEx m1(metaspace_lock(), Mutex::_no_safepoint_check_flag);
509 // Ensure _modules is stable, since it is examined without a lock
510 OrderAccess::release_store_ptr(&_modules, modules);
511 }
512 }
513 }
514 return modules;
515 }
516
517 oop ClassLoaderData::keep_alive_object() const {
518 assert_locked_or_safepoint(_metaspace_lock);
519 assert(!keep_alive(), "Don't use with CLDs that are artificially kept alive");
520 return is_anonymous() ? _klasses->java_mirror() : class_loader();
521 }
522
523 bool ClassLoaderData::is_alive(BoolObjectClosure* is_alive_closure) const {
524 bool alive = keep_alive() // null class loader and incomplete anonymous klasses.
525 || is_alive_closure->do_object_b(keep_alive_object());
526
527 return alive;
528 }
529
530 ClassLoaderData::~ClassLoaderData() {
531 // Release C heap structures for all the classes.
532 classes_do(InstanceKlass::release_C_heap_structures);
533
534 // Release C heap allocated hashtable for all the packages.
535 if (_packages != NULL) {
536 // Destroy the table itself
537 delete _packages;
538 _packages = NULL;
539 }
540
541 // Release C heap allocated hashtable for all the modules.
542 if (_modules != NULL) {
543 // Destroy the table itself
544 delete _modules;
545 _modules = NULL;
546 }
547
548 if (_unnamed_module != NULL) {
549 _unnamed_module->delete_unnamed_module();
550 _unnamed_module = NULL;
551 }
552
553 // release the metaspace
554 Metaspace *m = _metaspace;
555 if (m != NULL) {
556 _metaspace = NULL;
557 delete m;
558 }
559 // Clear all the JNI handles for methods
560 // These aren't deallocated and are going to look like a leak, but that's
561 // needed because we can't really get rid of jmethodIDs because we don't
562 // know when native code is going to stop using them. The spec says that
563 // they're "invalid" but existing programs likely rely on their being
564 // NULL after class unloading.
565 if (_jmethod_ids != NULL) {
566 Method::clear_jmethod_ids(this);
567 }
568 // Delete lock
569 delete _metaspace_lock;
570
571 // Delete free list
572 if (_deallocate_list != NULL) {
573 delete _deallocate_list;
574 }
575 }
576
577 // Returns true if this class loader data is for the system class loader.
578 bool ClassLoaderData::is_system_class_loader_data() const {
579 return SystemDictionary::is_system_class_loader(class_loader());
580 }
581
582 // Returns true if this class loader data is for the platform class loader.
583 bool ClassLoaderData::is_platform_class_loader_data() const {
584 return SystemDictionary::is_platform_class_loader(class_loader());
585 }
586
587 // Returns true if this class loader data is one of the 3 builtin
588 // (boot, application/system or platform) class loaders. Note, the
589 // builtin loaders are not freed by a GC.
590 bool ClassLoaderData::is_builtin_class_loader_data() const {
591 return (is_the_null_class_loader_data() ||
592 SystemDictionary::is_system_class_loader(class_loader()) ||
593 SystemDictionary::is_platform_class_loader(class_loader()));
594 }
595
596 Metaspace* ClassLoaderData::metaspace_non_null() {
597 assert(!DumpSharedSpaces, "wrong metaspace!");
598 // If the metaspace has not been allocated, create a new one. Might want
599 // to create smaller arena for Reflection class loaders also.
600 // The reason for the delayed allocation is because some class loaders are
601 // simply for delegating with no metadata of their own.
602 // Lock-free access requires load_ptr_acquire.
603 Metaspace* metaspace = load_ptr_acquire(&_metaspace);
604 if (metaspace == NULL) {
605 MutexLockerEx ml(_metaspace_lock, Mutex::_no_safepoint_check_flag);
606 // Check if _metaspace got allocated while we were waiting for this lock.
607 if ((metaspace = _metaspace) == NULL) {
608 if (this == the_null_class_loader_data()) {
609 assert (class_loader() == NULL, "Must be");
610 metaspace = new Metaspace(_metaspace_lock, Metaspace::BootMetaspaceType);
611 } else if (is_anonymous()) {
612 if (class_loader() != NULL) {
613 log_trace(class, loader, data)("is_anonymous: %s", class_loader()->klass()->internal_name());
614 }
615 metaspace = new Metaspace(_metaspace_lock, Metaspace::AnonymousMetaspaceType);
616 } else if (class_loader()->is_a(SystemDictionary::reflect_DelegatingClassLoader_klass())) {
617 if (class_loader() != NULL) {
618 log_trace(class, loader, data)("is_reflection: %s", class_loader()->klass()->internal_name());
619 }
620 metaspace = new Metaspace(_metaspace_lock, Metaspace::ReflectionMetaspaceType);
621 } else {
622 metaspace = new Metaspace(_metaspace_lock, Metaspace::StandardMetaspaceType);
623 }
624 // Ensure _metaspace is stable, since it is examined without a lock
625 OrderAccess::release_store_ptr(&_metaspace, metaspace);
626 }
627 }
628 return metaspace;
629 }
630
631 jobject ClassLoaderData::add_handle(Handle h) {
632 MutexLockerEx ml(metaspace_lock(), Mutex::_no_safepoint_check_flag);
633 return (jobject) _handles.add(h());
634 }
635
636 void ClassLoaderData::remove_handle_unsafe(jobject h) {
637 assert(_handles.contains((oop*) h), "Got unexpected handle " PTR_FORMAT, p2i((oop*) h));
638 *((oop*) h) = NULL;
639 }
640
641 // Add this metadata pointer to be freed when it's safe. This is only during
642 // class unloading because Handles might point to this metadata field.
643 void ClassLoaderData::add_to_deallocate_list(Metadata* m) {
644 // Metadata in shared region isn't deleted.
645 if (!m->is_shared()) {
646 MutexLockerEx ml(metaspace_lock(), Mutex::_no_safepoint_check_flag);
647 if (_deallocate_list == NULL) {
648 _deallocate_list = new (ResourceObj::C_HEAP, mtClass) GrowableArray<Metadata*>(100, true);
649 }
650 _deallocate_list->append_if_missing(m);
651 }
652 }
653
654 // Deallocate free metadata on the free list. How useful the PermGen was!
655 void ClassLoaderData::free_deallocate_list() {
656 // Don't need lock, at safepoint
657 assert(SafepointSynchronize::is_at_safepoint(), "only called at safepoint");
658 if (_deallocate_list == NULL) {
659 return;
660 }
661 // Go backwards because this removes entries that are freed.
662 for (int i = _deallocate_list->length() - 1; i >= 0; i--) {
663 Metadata* m = _deallocate_list->at(i);
664 if (!m->on_stack()) {
665 _deallocate_list->remove_at(i);
666 // There are only three types of metadata that we deallocate directly.
667 // Cast them so they can be used by the template function.
668 if (m->is_method()) {
669 MetadataFactory::free_metadata(this, (Method*)m);
670 } else if (m->is_constantPool()) {
671 MetadataFactory::free_metadata(this, (ConstantPool*)m);
672 } else if (m->is_klass()) {
673 MetadataFactory::free_metadata(this, (InstanceKlass*)m);
674 } else {
675 ShouldNotReachHere();
676 }
677 } else {
678 // Metadata is alive.
679 // If scratch_class is on stack then it shouldn't be on this list!
680 assert(!m->is_klass() || !((InstanceKlass*)m)->is_scratch_class(),
681 "scratch classes on this list should be dead");
682 // Also should assert that other metadata on the list was found in handles.
683 }
684 }
685 }
686
687 // These anonymous class loaders are to contain classes used for JSR292
688 ClassLoaderData* ClassLoaderData::anonymous_class_loader_data(oop loader, TRAPS) {
689 // Add a new class loader data to the graph.
690 Handle lh(THREAD, loader);
691 return ClassLoaderDataGraph::add(lh, true, THREAD);
692 }
693
694 const char* ClassLoaderData::loader_name() {
695 // Handles null class loader
696 return SystemDictionary::loader_name(class_loader());
697 }
698
699 #ifndef PRODUCT
700 // Define to dump klasses
701 #undef CLD_DUMP_KLASSES
702
703 void ClassLoaderData::dump(outputStream * const out) {
704 out->print("ClassLoaderData CLD: " PTR_FORMAT ", loader: " PTR_FORMAT ", loader_klass: " PTR_FORMAT " %s {",
705 p2i(this), p2i((void *)class_loader()),
706 p2i(class_loader() != NULL ? class_loader()->klass() : NULL), loader_name());
707 if (claimed()) out->print(" claimed ");
708 if (is_unloading()) out->print(" unloading ");
709 out->cr();
710 if (metaspace_or_null() != NULL) {
711 out->print_cr("metaspace: " INTPTR_FORMAT, p2i(metaspace_or_null()));
712 metaspace_or_null()->dump(out);
713 } else {
714 out->print_cr("metaspace: NULL");
715 }
716
717 #ifdef CLD_DUMP_KLASSES
718 if (Verbose) {
719 Klass* k = _klasses;
720 while (k != NULL) {
721 out->print_cr("klass " PTR_FORMAT ", %s, CT: %d, MUT: %d", k, k->name()->as_C_string(),
722 k->has_modified_oops(), k->has_accumulated_modified_oops());
723 assert(k != k->next_link(), "no loops!");
724 k = k->next_link();
725 }
726 }
727 #endif // CLD_DUMP_KLASSES
728 #undef CLD_DUMP_KLASSES
729 if (_jmethod_ids != NULL) {
730 Method::print_jmethod_ids(this, out);
731 }
732 out->print_cr("}");
733 }
734 #endif // PRODUCT
735
736 void ClassLoaderData::verify() {
737 assert_locked_or_safepoint(_metaspace_lock);
738 oop cl = class_loader();
739
740 guarantee(this == class_loader_data(cl) || is_anonymous(), "Must be the same");
741 guarantee(cl != NULL || this == ClassLoaderData::the_null_class_loader_data() || is_anonymous(), "must be");
742
743 // Verify the integrity of the allocated space.
744 if (metaspace_or_null() != NULL) {
745 metaspace_or_null()->verify();
746 }
747
748 for (Klass* k = _klasses; k != NULL; k = k->next_link()) {
749 guarantee(k->class_loader_data() == this, "Must be the same");
750 k->verify();
751 assert(k != k->next_link(), "no loops!");
752 }
753 }
754
755 bool ClassLoaderData::contains_klass(Klass* klass) {
756 // Lock-free access requires load_ptr_acquire
757 for (Klass* k = load_ptr_acquire(&_klasses); k != NULL; k = k->next_link()) {
758 if (k == klass) return true;
759 }
760 return false;
761 }
762
763
764 // GC root of class loader data created.
765 ClassLoaderData* ClassLoaderDataGraph::_head = NULL;
766 ClassLoaderData* ClassLoaderDataGraph::_unloading = NULL;
767 ClassLoaderData* ClassLoaderDataGraph::_saved_unloading = NULL;
768 ClassLoaderData* ClassLoaderDataGraph::_saved_head = NULL;
769
770 bool ClassLoaderDataGraph::_should_purge = false;
771 bool ClassLoaderDataGraph::_metaspace_oom = false;
772
773 // Add a new class loader data node to the list. Assign the newly created
774 // ClassLoaderData into the java/lang/ClassLoader object as a hidden field
775 ClassLoaderData* ClassLoaderDataGraph::add(Handle loader, bool is_anonymous, TRAPS) {
776 // We need to allocate all the oops for the ClassLoaderData before allocating the
777 // actual ClassLoaderData object.
778 ClassLoaderData::Dependencies dependencies(CHECK_NULL);
779
780 NoSafepointVerifier no_safepoints; // we mustn't GC until we've installed the
781 // ClassLoaderData in the graph since the CLD
782 // contains unhandled oops
783
784 ClassLoaderData* cld = new ClassLoaderData(loader, is_anonymous, dependencies);
785
786
787 if (!is_anonymous) {
788 ClassLoaderData** cld_addr = java_lang_ClassLoader::loader_data_addr(loader());
789 // First, Atomically set it
790 ClassLoaderData* old = (ClassLoaderData*) Atomic::cmpxchg_ptr(cld, cld_addr, NULL);
791 if (old != NULL) {
792 delete cld;
793 // Returns the data.
794 return old;
795 }
796 }
797
798 // We won the race, and therefore the task of adding the data to the list of
799 // class loader data
800 ClassLoaderData** list_head = &_head;
801 ClassLoaderData* next = _head;
802
803 do {
804 cld->set_next(next);
805 ClassLoaderData* exchanged = (ClassLoaderData*)Atomic::cmpxchg_ptr(cld, list_head, next);
806 if (exchanged == next) {
807 if (log_is_enabled(Debug, class, loader, data)) {
808 PauseNoSafepointVerifier pnsv(&no_safepoints); // Need safe points for JavaCalls::call_virtual
809 log_creation(loader, cld, CHECK_NULL);
810 }
811 return cld;
812 }
813 next = exchanged;
814 } while (true);
815 }
816
817 void ClassLoaderDataGraph::log_creation(Handle loader, ClassLoaderData* cld, TRAPS) {
818 Handle string;
819 if (loader.not_null()) {
820 // Include the result of loader.toString() in the output. This allows
821 // the user of the log to identify the class loader instance.
822 JavaValue result(T_OBJECT);
823 Klass* spec_klass = SystemDictionary::ClassLoader_klass();
824 JavaCalls::call_virtual(&result,
825 loader,
826 spec_klass,
827 vmSymbols::toString_name(),
828 vmSymbols::void_string_signature(),
829 CHECK);
830 assert(result.get_type() == T_OBJECT, "just checking");
831 string = Handle(THREAD, (oop)result.get_jobject());
832 }
833
834 ResourceMark rm;
835 outputStream* log = Log(class, loader, data)::debug_stream();
836 log->print("create class loader data " INTPTR_FORMAT, p2i(cld));
837 log->print(" for instance " INTPTR_FORMAT " of %s", p2i((void *)cld->class_loader()),
838 cld->loader_name());
839
840 if (string.not_null()) {
841 log->print(": ");
842 java_lang_String::print(string(), log);
843 }
844 log->cr();
845 }
846
847
848 void ClassLoaderDataGraph::oops_do(OopClosure* f, KlassClosure* klass_closure, bool must_claim) {
849 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
850 cld->oops_do(f, klass_closure, must_claim);
851 }
852 }
853
854 void ClassLoaderDataGraph::keep_alive_oops_do(OopClosure* f, KlassClosure* klass_closure, bool must_claim) {
855 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
856 if (cld->keep_alive()) {
857 cld->oops_do(f, klass_closure, must_claim);
858 }
859 }
860 }
861
862 void ClassLoaderDataGraph::always_strong_oops_do(OopClosure* f, KlassClosure* klass_closure, bool must_claim) {
863 if (ClassUnloading) {
864 keep_alive_oops_do(f, klass_closure, must_claim);
865 } else {
866 oops_do(f, klass_closure, must_claim);
867 }
868 }
869
870 void ClassLoaderDataGraph::cld_do(CLDClosure* cl) {
871 for (ClassLoaderData* cld = _head; cl != NULL && cld != NULL; cld = cld->next()) {
872 cl->do_cld(cld);
873 }
874 }
875
876 void ClassLoaderDataGraph::cld_unloading_do(CLDClosure* cl) {
877 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
878 // Only walk the head until any clds not purged from prior unloading
879 // (CMS doesn't purge right away).
880 for (ClassLoaderData* cld = _unloading; cld != _saved_unloading; cld = cld->next()) {
881 assert(cld->is_unloading(), "invariant");
882 cl->do_cld(cld);
883 }
884 }
885
886 void ClassLoaderDataGraph::roots_cld_do(CLDClosure* strong, CLDClosure* weak) {
887 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->_next) {
888 CLDClosure* closure = cld->keep_alive() ? strong : weak;
889 if (closure != NULL) {
890 closure->do_cld(cld);
891 }
892 }
893 }
894
895 void ClassLoaderDataGraph::keep_alive_cld_do(CLDClosure* cl) {
896 roots_cld_do(cl, NULL);
897 }
898
899 void ClassLoaderDataGraph::always_strong_cld_do(CLDClosure* cl) {
900 if (ClassUnloading) {
901 keep_alive_cld_do(cl);
902 } else {
903 cld_do(cl);
904 }
905 }
906
907 void ClassLoaderDataGraph::classes_do(KlassClosure* klass_closure) {
908 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
909 cld->classes_do(klass_closure);
910 }
911 }
912
913 void ClassLoaderDataGraph::classes_do(void f(Klass* const)) {
914 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
915 cld->classes_do(f);
916 }
917 }
918
919 void ClassLoaderDataGraph::methods_do(void f(Method*)) {
920 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
921 cld->methods_do(f);
922 }
923 }
924
925 void ClassLoaderDataGraph::modules_do(void f(ModuleEntry*)) {
926 assert_locked_or_safepoint(Module_lock);
927 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
928 cld->modules_do(f);
929 }
930 }
931
932 void ClassLoaderDataGraph::modules_unloading_do(void f(ModuleEntry*)) {
933 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
934 // Only walk the head until any clds not purged from prior unloading
935 // (CMS doesn't purge right away).
936 for (ClassLoaderData* cld = _unloading; cld != _saved_unloading; cld = cld->next()) {
937 assert(cld->is_unloading(), "invariant");
938 cld->modules_do(f);
939 }
940 }
941
942 void ClassLoaderDataGraph::packages_do(void f(PackageEntry*)) {
943 assert_locked_or_safepoint(Module_lock);
944 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
945 cld->packages_do(f);
946 }
947 }
948
949 void ClassLoaderDataGraph::packages_unloading_do(void f(PackageEntry*)) {
950 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
951 // Only walk the head until any clds not purged from prior unloading
952 // (CMS doesn't purge right away).
953 for (ClassLoaderData* cld = _unloading; cld != _saved_unloading; cld = cld->next()) {
954 assert(cld->is_unloading(), "invariant");
955 cld->packages_do(f);
956 }
957 }
958
959 void ClassLoaderDataGraph::loaded_classes_do(KlassClosure* klass_closure) {
960 for (ClassLoaderData* cld = _head; cld != NULL; cld = cld->next()) {
961 cld->loaded_classes_do(klass_closure);
962 }
963 }
964
965 void ClassLoaderDataGraph::classes_unloading_do(void f(Klass* const)) {
966 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
967 // Only walk the head until any clds not purged from prior unloading
968 // (CMS doesn't purge right away).
969 for (ClassLoaderData* cld = _unloading; cld != _saved_unloading; cld = cld->next()) {
970 assert(cld->is_unloading(), "invariant");
971 cld->classes_do(f);
972 }
973 }
974
975 GrowableArray<ClassLoaderData*>* ClassLoaderDataGraph::new_clds() {
976 assert(_head == NULL || _saved_head != NULL, "remember_new_clds(true) not called?");
977
978 GrowableArray<ClassLoaderData*>* array = new GrowableArray<ClassLoaderData*>();
979
980 // The CLDs in [_head, _saved_head] were all added during last call to remember_new_clds(true);
981 ClassLoaderData* curr = _head;
982 while (curr != _saved_head) {
983 if (!curr->claimed()) {
984 array->push(curr);
985
986 if (log_is_enabled(Debug, class, loader, data)) {
987 outputStream* log = Log(class, loader, data)::debug_stream();
988 log->print("found new CLD: ");
989 curr->print_value_on(log);
990 log->cr();
991 }
992 }
993
994 curr = curr->_next;
995 }
996
997 return array;
998 }
999
1000 bool ClassLoaderDataGraph::unload_list_contains(const void* x) {
1001 assert(SafepointSynchronize::is_at_safepoint(), "only safe to call at safepoint");
1002 for (ClassLoaderData* cld = _unloading; cld != NULL; cld = cld->next()) {
1003 if (cld->metaspace_or_null() != NULL && cld->metaspace_or_null()->contains(x)) {
1004 return true;
1005 }
1006 }
1007 return false;
1008 }
1009
1010 #ifndef PRODUCT
1011 bool ClassLoaderDataGraph::contains_loader_data(ClassLoaderData* loader_data) {
1012 for (ClassLoaderData* data = _head; data != NULL; data = data->next()) {
1013 if (loader_data == data) {
1014 return true;
1015 }
1016 }
1017
1018 return false;
1019 }
1020 #endif // PRODUCT
1021
1022
1023 // Move class loader data from main list to the unloaded list for unloading
1024 // and deallocation later.
1025 bool ClassLoaderDataGraph::do_unloading(BoolObjectClosure* is_alive_closure,
1026 bool clean_previous_versions) {
1027
1028 ClassLoaderData* data = _head;
1029 ClassLoaderData* prev = NULL;
1030 bool seen_dead_loader = false;
1031
1032 // Mark metadata seen on the stack only so we can delete unneeded entries.
1033 // Only walk all metadata, including the expensive code cache walk, for Full GC
1034 // and only if class redefinition and if there's previous versions of
1035 // Klasses to delete.
1036 bool walk_all_metadata = clean_previous_versions &&
1037 JvmtiExport::has_redefined_a_class() &&
1038 InstanceKlass::has_previous_versions_and_reset();
1039 MetadataOnStackMark md_on_stack(walk_all_metadata);
1040
1041 // Save previous _unloading pointer for CMS which may add to unloading list before
1042 // purging and we don't want to rewalk the previously unloaded class loader data.
1043 _saved_unloading = _unloading;
1044
1045 data = _head;
1046 while (data != NULL) {
1047 if (data->is_alive(is_alive_closure)) {
1048 // clean metaspace
1049 if (walk_all_metadata) {
1050 data->classes_do(InstanceKlass::purge_previous_versions);
1051 }
1052 data->free_deallocate_list();
1053 prev = data;
1054 data = data->next();
1055 continue;
1056 }
1057 seen_dead_loader = true;
1058 ClassLoaderData* dead = data;
1059 dead->unload();
1060 data = data->next();
1061 // Remove from loader list.
1062 // This class loader data will no longer be found
1063 // in the ClassLoaderDataGraph.
1064 if (prev != NULL) {
1065 prev->set_next(data);
1066 } else {
1067 assert(dead == _head, "sanity check");
1068 _head = data;
1069 }
1070 dead->set_next(_unloading);
1071 _unloading = dead;
1072 }
1073
1074 if (seen_dead_loader) {
1075 // Walk a ModuleEntry's reads and a PackageEntry's exports lists
1076 // to determine if there are modules on those lists that are now
1077 // dead and should be removed. A module's life cycle is equivalent
1078 // to its defining class loader's life cycle. Since a module is
1079 // considered dead if its class loader is dead, these walks must
1080 // occur after each class loader's aliveness is determined.
1081 data = _head;
1082 while (data != NULL) {
1083 if (data->packages() != NULL) {
1084 data->packages()->purge_all_package_exports();
1085 }
1086 if (data->modules_defined()) {
1087 data->modules()->purge_all_module_reads();
1088 }
1089 data = data->next();
1090 }
1091
1092 post_class_unload_events();
1093 }
1094
1095 return seen_dead_loader;
1096 }
1097
1098 void ClassLoaderDataGraph::purge() {
1099 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
1100 ClassLoaderData* list = _unloading;
1101 _unloading = NULL;
1102 ClassLoaderData* next = list;
1103 bool classes_unloaded = false;
1104 while (next != NULL) {
1105 ClassLoaderData* purge_me = next;
1106 next = purge_me->next();
1107 delete purge_me;
1108 classes_unloaded = true;
1109 }
1110 if (classes_unloaded) {
1111 Metaspace::purge();
1112 set_metaspace_oom(false);
1113 }
1114 }
1115
1116 void ClassLoaderDataGraph::post_class_unload_events() {
1117 #if INCLUDE_TRACE
1118 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint!");
1119 if (Tracing::enabled()) {
1120 if (Tracing::is_event_enabled(TraceClassUnloadEvent)) {
1121 assert(_unloading != NULL, "need class loader data unload list!");
1122 _class_unload_time = Ticks::now();
1123 classes_unloading_do(&class_unload_event);
1124 }
1125 Tracing::on_unloading_classes();
1126 }
1127 #endif
1128 }
1129
1130 // CDS support
1131
1132 // Global metaspaces for writing information to the shared archive. When
1133 // application CDS is supported, we may need one per metaspace, so this
1134 // sort of looks like it.
1135 Metaspace* ClassLoaderData::_ro_metaspace = NULL;
1136 Metaspace* ClassLoaderData::_rw_metaspace = NULL;
1137 static bool _shared_metaspaces_initialized = false;
1138
1139 // Initialize shared metaspaces (change to call from somewhere not lazily)
1140 void ClassLoaderData::initialize_shared_metaspaces() {
1141 assert(DumpSharedSpaces, "only use this for dumping shared spaces");
1142 assert(this == ClassLoaderData::the_null_class_loader_data(),
1143 "only supported for null loader data for now");
1144 assert (!_shared_metaspaces_initialized, "only initialize once");
1145 MutexLockerEx ml(metaspace_lock(), Mutex::_no_safepoint_check_flag);
1146 _ro_metaspace = new Metaspace(_metaspace_lock, Metaspace::ROMetaspaceType);
1147 _rw_metaspace = new Metaspace(_metaspace_lock, Metaspace::ReadWriteMetaspaceType);
1148 _shared_metaspaces_initialized = true;
1149 }
1150
1151 Metaspace* ClassLoaderData::ro_metaspace() {
1152 assert(_ro_metaspace != NULL, "should already be initialized");
1153 return _ro_metaspace;
1154 }
1155
1156 Metaspace* ClassLoaderData::rw_metaspace() {
1157 assert(_rw_metaspace != NULL, "should already be initialized");
1158 return _rw_metaspace;
1159 }
1160
1161 ClassLoaderDataGraphKlassIteratorAtomic::ClassLoaderDataGraphKlassIteratorAtomic()
1162 : _next_klass(NULL) {
1163 ClassLoaderData* cld = ClassLoaderDataGraph::_head;
1164 Klass* klass = NULL;
1165
1166 // Find the first klass in the CLDG.
1167 while (cld != NULL) {
1168 assert_locked_or_safepoint(cld->metaspace_lock());
1169 klass = cld->_klasses;
1170 if (klass != NULL) {
1171 _next_klass = klass;
1172 return;
1173 }
1174 cld = cld->next();
1175 }
1176 }
1177
1178 Klass* ClassLoaderDataGraphKlassIteratorAtomic::next_klass_in_cldg(Klass* klass) {
1179 Klass* next = klass->next_link();
1180 if (next != NULL) {
1181 return next;
1182 }
1183
1184 // No more klasses in the current CLD. Time to find a new CLD.
1185 ClassLoaderData* cld = klass->class_loader_data();
1186 assert_locked_or_safepoint(cld->metaspace_lock());
1187 while (next == NULL) {
1188 cld = cld->next();
1189 if (cld == NULL) {
1190 break;
1191 }
1192 next = cld->_klasses;
1193 }
1194
1195 return next;
1196 }
1197
1198 Klass* ClassLoaderDataGraphKlassIteratorAtomic::next_klass() {
1199 Klass* head = _next_klass;
1200
1201 while (head != NULL) {
1202 Klass* next = next_klass_in_cldg(head);
1203
1204 Klass* old_head = (Klass*)Atomic::cmpxchg_ptr(next, &_next_klass, head);
1205
1206 if (old_head == head) {
1207 return head; // Won the CAS.
1208 }
1209
1210 head = old_head;
1211 }
1212
1213 // Nothing more for the iterator to hand out.
1214 assert(head == NULL, "head is " PTR_FORMAT ", expected not null:", p2i(head));
1215 return NULL;
1216 }
1217
1218 ClassLoaderDataGraphMetaspaceIterator::ClassLoaderDataGraphMetaspaceIterator() {
1219 _data = ClassLoaderDataGraph::_head;
1220 }
1221
1222 ClassLoaderDataGraphMetaspaceIterator::~ClassLoaderDataGraphMetaspaceIterator() {}
1223
1224 #ifndef PRODUCT
1225 // callable from debugger
1226 extern "C" int print_loader_data_graph() {
1227 ClassLoaderDataGraph::dump_on(tty);
1228 return 0;
1229 }
1230
1231 void ClassLoaderDataGraph::verify() {
1232 for (ClassLoaderData* data = _head; data != NULL; data = data->next()) {
1233 data->verify();
1234 }
1235 }
1236
1237 void ClassLoaderDataGraph::dump_on(outputStream * const out) {
1238 for (ClassLoaderData* data = _head; data != NULL; data = data->next()) {
1239 data->dump(out);
1240 }
1241 MetaspaceAux::dump(out);
1242 }
1243 #endif // PRODUCT
1244
1245 void ClassLoaderData::print_value_on(outputStream* out) const {
1246 if (class_loader() == NULL) {
1247 out->print("NULL class_loader");
1248 } else {
1249 out->print("class loader " INTPTR_FORMAT " ", p2i(this));
1250 class_loader()->print_value_on(out);
1251 }
1252 }
1253
1254 #if INCLUDE_TRACE
1255
1256 Ticks ClassLoaderDataGraph::_class_unload_time;
1257
1258 void ClassLoaderDataGraph::class_unload_event(Klass* const k) {
1259 assert(k != NULL, "invariant");
1260
1261 // post class unload event
1262 EventClassUnload event(UNTIMED);
1263 event.set_endtime(_class_unload_time);
1264 event.set_unloadedClass(k);
1265 event.set_definingClassLoader(k->class_loader_data());
1266 event.commit();
1267 }
1268
1269 #endif // INCLUDE_TRACE