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