1 /*
2 * Copyright (c) 2015, 2023, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2020, 2021, Red Hat, Inc. and/or its affiliates.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "classfile/javaClasses.hpp"
28 #include "gc/shared/workerThread.hpp"
29 #include "gc/shenandoah/shenandoahClosures.inline.hpp"
30 #include "gc/shenandoah/shenandoahReferenceProcessor.hpp"
31 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
32 #include "gc/shenandoah/shenandoahUtils.hpp"
33 #include "runtime/atomic.hpp"
34 #include "logging/log.hpp"
35
36 static ReferenceType reference_type(oop reference) {
37 return InstanceKlass::cast(reference->klass())->reference_type();
38 }
39
40 static const char* reference_type_name(ReferenceType type) {
41 switch (type) {
42 case REF_SOFT:
43 return "Soft";
44
45 case REF_WEAK:
46 return "Weak";
47
48 case REF_FINAL:
49 return "Final";
50
51 case REF_PHANTOM:
52 return "Phantom";
53
54 default:
55 ShouldNotReachHere();
56 return nullptr;
57 }
58 }
59
60 template <typename T>
61 static void set_oop_field(T* field, oop value);
62
63 template <>
64 void set_oop_field<oop>(oop* field, oop value) {
65 *field = value;
66 }
67
68 template <>
69 void set_oop_field<narrowOop>(narrowOop* field, oop value) {
70 *field = CompressedOops::encode(value);
71 }
72
73 static oop lrb(oop obj) {
74 if (obj != nullptr && ShenandoahHeap::heap()->marking_context()->is_marked(obj)) {
75 return ShenandoahBarrierSet::barrier_set()->load_reference_barrier(obj);
76 } else {
77 return obj;
78 }
79 }
80
81 template <typename T>
82 static volatile T* reference_referent_addr(oop reference) {
83 return (volatile T*)java_lang_ref_Reference::referent_addr_raw(reference);
84 }
85
86 inline oop reference_coop_decode_raw(narrowOop v) {
87 return CompressedOops::is_null(v) ? nullptr : CompressedOops::decode_raw(v);
88 }
89
90 inline oop reference_coop_decode_raw(oop v) {
91 return v;
92 }
93
94 // Raw referent, it can be dead. You cannot treat it as oop without additional safety
95 // checks, this is why it is HeapWord*. The decoding uses a special-case inlined
96 // CompressedOops::decode method that bypasses normal oop-ness checks.
97 template <typename T>
98 static HeapWord* reference_referent_raw(oop reference) {
99 T raw_oop = Atomic::load(reference_referent_addr<T>(reference));
100 return cast_from_oop<HeapWord*>(reference_coop_decode_raw(raw_oop));
101 }
102
103 static void reference_clear_referent(oop reference) {
104 java_lang_ref_Reference::clear_referent_raw(reference);
105 }
106
107 template <typename T>
108 static T* reference_discovered_addr(oop reference) {
109 return reinterpret_cast<T*>(java_lang_ref_Reference::discovered_addr_raw(reference));
110 }
111
112 template <typename T>
113 static oop reference_discovered(oop reference) {
114 T heap_oop = *reference_discovered_addr<T>(reference);
115 return lrb(CompressedOops::decode(heap_oop));
116 }
117
118 template <typename T>
119 static void reference_set_discovered(oop reference, oop discovered);
120
121 template <>
122 void reference_set_discovered<oop>(oop reference, oop discovered) {
123 *reference_discovered_addr<oop>(reference) = discovered;
124 }
125
126 template <>
127 void reference_set_discovered<narrowOop>(oop reference, oop discovered) {
128 *reference_discovered_addr<narrowOop>(reference) = CompressedOops::encode(discovered);
129 }
130
131 template<typename T>
132 static bool reference_cas_discovered(oop reference, oop discovered) {
133 T* addr = reinterpret_cast<T *>(java_lang_ref_Reference::discovered_addr_raw(reference));
134 return ShenandoahHeap::atomic_update_oop_check(discovered, addr, nullptr);
135 }
136
137 template <typename T>
138 static T* reference_next_addr(oop reference) {
139 return reinterpret_cast<T*>(java_lang_ref_Reference::next_addr_raw(reference));
140 }
141
142 template <typename T>
143 static oop reference_next(oop reference) {
144 T heap_oop = RawAccess<>::oop_load(reference_next_addr<T>(reference));
145 return lrb(CompressedOops::decode(heap_oop));
146 }
147
148 static void reference_set_next(oop reference, oop next) {
149 java_lang_ref_Reference::set_next_raw(reference, next);
150 }
151
152 static void soft_reference_update_clock() {
153 const jlong now = os::javaTimeNanos() / NANOSECS_PER_MILLISEC;
154 java_lang_ref_SoftReference::set_clock(now);
155 }
156
157 ShenandoahRefProcThreadLocal::ShenandoahRefProcThreadLocal() :
158 _discovered_list(nullptr),
159 _encountered_count(),
160 _discovered_count(),
161 _enqueued_count() {
162 }
163
164 void ShenandoahRefProcThreadLocal::reset() {
165 _discovered_list = nullptr;
166 _mark_closure = nullptr;
167 for (uint i = 0; i < reference_type_count; i++) {
168 _encountered_count[i] = 0;
169 _discovered_count[i] = 0;
170 _enqueued_count[i] = 0;
171 }
172 }
173
174 template <typename T>
175 T* ShenandoahRefProcThreadLocal::discovered_list_addr() {
176 return reinterpret_cast<T*>(&_discovered_list);
177 }
178
179 template <>
180 oop ShenandoahRefProcThreadLocal::discovered_list_head<oop>() const {
181 return *reinterpret_cast<const oop*>(&_discovered_list);
182 }
183
184 template <>
185 oop ShenandoahRefProcThreadLocal::discovered_list_head<narrowOop>() const {
186 return CompressedOops::decode(*reinterpret_cast<const narrowOop*>(&_discovered_list));
187 }
188
189 template <>
190 void ShenandoahRefProcThreadLocal::set_discovered_list_head<narrowOop>(oop head) {
191 *discovered_list_addr<narrowOop>() = CompressedOops::encode(head);
192 }
193
194 template <>
195 void ShenandoahRefProcThreadLocal::set_discovered_list_head<oop>(oop head) {
196 *discovered_list_addr<oop>() = head;
197 }
198
199 ShenandoahReferenceProcessor::ShenandoahReferenceProcessor(uint max_workers) :
200 _soft_reference_policy(nullptr),
201 _ref_proc_thread_locals(NEW_C_HEAP_ARRAY(ShenandoahRefProcThreadLocal, max_workers, mtGC)),
202 _pending_list(nullptr),
203 _pending_list_tail(&_pending_list),
204 _iterate_discovered_list_id(0U),
205 _stats() {
206 for (size_t i = 0; i < max_workers; i++) {
207 _ref_proc_thread_locals[i].reset();
208 }
209 }
210
211 void ShenandoahReferenceProcessor::reset_thread_locals() {
212 uint max_workers = ShenandoahHeap::heap()->max_workers();
213 for (uint i = 0; i < max_workers; i++) {
214 _ref_proc_thread_locals[i].reset();
215 }
216 }
217
218 void ShenandoahReferenceProcessor::set_mark_closure(uint worker_id, ShenandoahMarkRefsSuperClosure* mark_closure) {
219 _ref_proc_thread_locals[worker_id].set_mark_closure(mark_closure);
220 }
221
222 void ShenandoahReferenceProcessor::set_soft_reference_policy(bool clear) {
223 static AlwaysClearPolicy always_clear_policy;
224 static LRUMaxHeapPolicy lru_max_heap_policy;
225
226 if (clear) {
227 log_info(gc, ref)("Clearing All SoftReferences");
228 _soft_reference_policy = &always_clear_policy;
229 } else {
230 _soft_reference_policy = &lru_max_heap_policy;
231 }
232
233 _soft_reference_policy->setup();
234 }
235
236 template <typename T>
237 bool ShenandoahReferenceProcessor::is_inactive(oop reference, oop referent, ReferenceType type) const {
238 if (type == REF_FINAL) {
239 // A FinalReference is inactive if its next field is non-null. An application can't
240 // call enqueue() or clear() on a FinalReference.
241 return reference_next<T>(reference) != nullptr;
242 } else {
243 // A non-FinalReference is inactive if the referent is null. The referent can only
244 // be null if the application called Reference.enqueue() or Reference.clear().
245 return referent == nullptr;
246 }
247 }
248
249 bool ShenandoahReferenceProcessor::is_strongly_live(oop referent) const {
250 return ShenandoahHeap::heap()->marking_context()->is_marked_strong(referent);
251 }
252
253 bool ShenandoahReferenceProcessor::is_softly_live(oop reference, ReferenceType type) const {
254 if (type != REF_SOFT) {
255 // Not a SoftReference
256 return false;
257 }
258
259 // Ask SoftReference policy
260 const jlong clock = java_lang_ref_SoftReference::clock();
261 assert(clock != 0, "Clock not initialized");
262 assert(_soft_reference_policy != nullptr, "Policy not initialized");
263 return !_soft_reference_policy->should_clear_reference(reference, clock);
264 }
265
266 template <typename T>
267 bool ShenandoahReferenceProcessor::should_discover(oop reference, ReferenceType type) const {
268 T* referent_addr = (T*) java_lang_ref_Reference::referent_addr_raw(reference);
269 T heap_oop = RawAccess<>::oop_load(referent_addr);
270 oop referent = CompressedOops::decode(heap_oop);
271
272 if (is_inactive<T>(reference, referent, type)) {
273 log_trace(gc,ref)("Reference inactive: " PTR_FORMAT, p2i(reference));
274 return false;
275 }
276
277 if (is_strongly_live(referent)) {
278 log_trace(gc,ref)("Reference strongly live: " PTR_FORMAT, p2i(reference));
279 return false;
280 }
281
282 if (is_softly_live(reference, type)) {
283 log_trace(gc,ref)("Reference softly live: " PTR_FORMAT, p2i(reference));
284 return false;
285 }
286
287 return true;
288 }
289
290 template <typename T>
291 bool ShenandoahReferenceProcessor::should_drop(oop reference, ReferenceType type) const {
292 HeapWord* raw_referent = reference_referent_raw<T>(reference);
293 if (raw_referent == nullptr) {
294 // Reference has been cleared, by a call to Reference.enqueue()
295 // or Reference.clear() from the application, which means we
296 // should drop the reference.
297 return true;
298 }
299
300 // Check if the referent is still alive, in which case we should
301 // drop the reference.
302 if (type == REF_PHANTOM) {
303 return ShenandoahHeap::heap()->complete_marking_context()->is_marked(raw_referent);
304 } else {
305 return ShenandoahHeap::heap()->complete_marking_context()->is_marked_strong(raw_referent);
306 }
307 }
308
309 template <typename T>
310 void ShenandoahReferenceProcessor::make_inactive(oop reference, ReferenceType type) const {
311 if (type == REF_FINAL) {
312 // Don't clear referent. It is needed by the Finalizer thread to make the call
313 // to finalize(). A FinalReference is instead made inactive by self-looping the
314 // next field. An application can't call FinalReference.enqueue(), so there is
315 // no race to worry about when setting the next field.
316 assert(reference_next<T>(reference) == nullptr, "Already inactive");
317 assert(ShenandoahHeap::heap()->marking_context()->is_marked(reference_referent_raw<T>(reference)), "only make inactive final refs with alive referents");
318 reference_set_next(reference, reference);
319 } else {
320 // Clear referent
321 reference_clear_referent(reference);
322 }
323 }
324
325 template <typename T>
326 bool ShenandoahReferenceProcessor::discover(oop reference, ReferenceType type, uint worker_id) {
327 if (!should_discover<T>(reference, type)) {
328 // Not discovered
329 return false;
330 }
331
332 if (reference_discovered<T>(reference) != nullptr) {
333 // Already discovered. This can happen if the reference is marked finalizable first, and then strong,
334 // in which case it will be seen 2x by marking.
335 log_trace(gc,ref)("Reference already discovered: " PTR_FORMAT, p2i(reference));
336 return true;
337 }
338
339 if (type == REF_FINAL) {
340 ShenandoahMarkRefsSuperClosure* cl = _ref_proc_thread_locals[worker_id].mark_closure();
341 bool weak = cl->is_weak();
342 cl->set_weak(true);
343 if (UseCompressedOops) {
344 cl->do_oop(reinterpret_cast<narrowOop*>(java_lang_ref_Reference::referent_addr_raw(reference)));
345 } else {
346 cl->do_oop(reinterpret_cast<oop*>(java_lang_ref_Reference::referent_addr_raw(reference)));
347 }
348 cl->set_weak(weak);
349 }
350
351 // Add reference to discovered list
352 ShenandoahRefProcThreadLocal& refproc_data = _ref_proc_thread_locals[worker_id];
353 oop discovered_head = refproc_data.discovered_list_head<T>();
354 if (discovered_head == nullptr) {
355 // Self-loop tail of list. We distinguish discovered from not-discovered references by looking at their
356 // discovered field: if it is null, then it is not-yet discovered, otherwise it is discovered
357 discovered_head = reference;
358 }
359 if (reference_cas_discovered<T>(reference, discovered_head)) {
360 refproc_data.set_discovered_list_head<T>(reference);
361 assert(refproc_data.discovered_list_head<T>() == reference, "reference must be new discovered head");
362 log_trace(gc, ref)("Discovered Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
363 _ref_proc_thread_locals[worker_id].inc_discovered(type);
364 }
365 return true;
366 }
367
368 bool ShenandoahReferenceProcessor::discover_reference(oop reference, ReferenceType type) {
369 if (!RegisterReferences) {
370 // Reference processing disabled
371 return false;
372 }
373
374 log_trace(gc, ref)("Encountered Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
375 uint worker_id = WorkerThread::worker_id();
376 _ref_proc_thread_locals[worker_id].inc_encountered(type);
377
378 if (UseCompressedOops) {
379 return discover<narrowOop>(reference, type, worker_id);
380 } else {
381 return discover<oop>(reference, type, worker_id);
382 }
383 }
384
385 template <typename T>
386 oop ShenandoahReferenceProcessor::drop(oop reference, ReferenceType type) {
387 log_trace(gc, ref)("Dropped Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
388
389 #ifdef ASSERT
390 HeapWord* raw_referent = reference_referent_raw<T>(reference);
391 assert(raw_referent == nullptr || ShenandoahHeap::heap()->marking_context()->is_marked(raw_referent),
392 "only drop references with alive referents");
393 #endif
394
395 // Unlink and return next in list
396 oop next = reference_discovered<T>(reference);
397 reference_set_discovered<T>(reference, nullptr);
398 return next;
399 }
400
401 template <typename T>
402 T* ShenandoahReferenceProcessor::keep(oop reference, ReferenceType type, uint worker_id) {
403 log_trace(gc, ref)("Enqueued Reference: " PTR_FORMAT " (%s)", p2i(reference), reference_type_name(type));
404
405 // Update statistics
406 _ref_proc_thread_locals[worker_id].inc_enqueued(type);
407
408 // Make reference inactive
409 make_inactive<T>(reference, type);
410
411 // Return next in list
412 return reference_discovered_addr<T>(reference);
413 }
414
415 template <typename T>
416 void ShenandoahReferenceProcessor::process_references(ShenandoahRefProcThreadLocal& refproc_data, uint worker_id) {
417 log_trace(gc, ref)("Processing discovered list #%u : " PTR_FORMAT, worker_id, p2i(refproc_data.discovered_list_head<T>()));
418 T* list = refproc_data.discovered_list_addr<T>();
419 // The list head is basically a GC root, we need to resolve and update it,
420 // otherwise we will later swap a from-space ref into Universe::pending_list().
421 if (!CompressedOops::is_null(*list)) {
422 oop first_resolved = lrb(CompressedOops::decode_not_null(*list));
423 set_oop_field(list, first_resolved);
424 }
425 T* p = list;
426 while (true) {
427 const oop reference = lrb(CompressedOops::decode(*p));
428 if (reference == nullptr) {
429 break;
430 }
431 log_trace(gc, ref)("Processing reference: " PTR_FORMAT, p2i(reference));
432 const ReferenceType type = reference_type(reference);
433
434 if (should_drop<T>(reference, type)) {
435 set_oop_field(p, drop<T>(reference, type));
436 } else {
437 p = keep<T>(reference, type, worker_id);
438 }
439
440 const oop discovered = lrb(reference_discovered<T>(reference));
441 if (reference == discovered) {
442 // Reset terminating self-loop to null
443 reference_set_discovered<T>(reference, oop(nullptr));
444 break;
445 }
446 }
447
448 // Prepend discovered references to internal pending list
449 if (!CompressedOops::is_null(*list)) {
450 oop head = lrb(CompressedOops::decode_not_null(*list));
451 shenandoah_assert_not_in_cset_except(&head, head, ShenandoahHeap::heap()->cancelled_gc() || !ShenandoahLoadRefBarrier);
452 oop prev = Atomic::xchg(&_pending_list, head);
453 RawAccess<>::oop_store(p, prev);
454 if (prev == nullptr) {
455 // First to prepend to list, record tail
456 _pending_list_tail = reinterpret_cast<void*>(p);
457 }
458
459 // Clear discovered list
460 set_oop_field(list, oop(nullptr));
461 }
462 }
463
464 void ShenandoahReferenceProcessor::work() {
465 // Process discovered references
466 uint max_workers = ShenandoahHeap::heap()->max_workers();
467 uint worker_id = Atomic::add(&_iterate_discovered_list_id, 1U, memory_order_relaxed) - 1;
468 while (worker_id < max_workers) {
469 if (UseCompressedOops) {
470 process_references<narrowOop>(_ref_proc_thread_locals[worker_id], worker_id);
471 } else {
472 process_references<oop>(_ref_proc_thread_locals[worker_id], worker_id);
473 }
474 worker_id = Atomic::add(&_iterate_discovered_list_id, 1U, memory_order_relaxed) - 1;
475 }
476 }
477
478 class ShenandoahReferenceProcessorTask : public WorkerTask {
479 private:
480 bool const _concurrent;
481 ShenandoahPhaseTimings::Phase const _phase;
482 ShenandoahReferenceProcessor* const _reference_processor;
483
484 public:
485 ShenandoahReferenceProcessorTask(ShenandoahPhaseTimings::Phase phase, bool concurrent, ShenandoahReferenceProcessor* reference_processor) :
486 WorkerTask("ShenandoahReferenceProcessorTask"),
487 _concurrent(concurrent),
488 _phase(phase),
489 _reference_processor(reference_processor) {
490 }
491
492 virtual void work(uint worker_id) {
493 if (_concurrent) {
494 ShenandoahConcurrentWorkerSession worker_session(worker_id);
495 ShenandoahWorkerTimingsTracker x(_phase, ShenandoahPhaseTimings::WeakRefProc, worker_id);
496 _reference_processor->work();
497 } else {
498 ShenandoahParallelWorkerSession worker_session(worker_id);
499 ShenandoahWorkerTimingsTracker x(_phase, ShenandoahPhaseTimings::WeakRefProc, worker_id);
500 _reference_processor->work();
501 }
502 }
503 };
504
505 void ShenandoahReferenceProcessor::process_references(ShenandoahPhaseTimings::Phase phase, WorkerThreads* workers, bool concurrent) {
506
507 Atomic::release_store_fence(&_iterate_discovered_list_id, 0U);
508
509 // Process discovered lists
510 ShenandoahReferenceProcessorTask task(phase, concurrent, this);
511 workers->run_task(&task);
512
513 // Update SoftReference clock
514 soft_reference_update_clock();
515
516 // Collect, log and trace statistics
517 collect_statistics();
518
519 enqueue_references(concurrent);
520 }
521
522 void ShenandoahReferenceProcessor::enqueue_references_locked() {
523 // Prepend internal pending list to external pending list
524 shenandoah_assert_not_in_cset_except(&_pending_list, _pending_list, ShenandoahHeap::heap()->cancelled_gc() || !ShenandoahLoadRefBarrier);
525 if (UseCompressedOops) {
526 *reinterpret_cast<narrowOop*>(_pending_list_tail) = CompressedOops::encode(Universe::swap_reference_pending_list(_pending_list));
527 } else {
528 *reinterpret_cast<oop*>(_pending_list_tail) = Universe::swap_reference_pending_list(_pending_list);
529 }
530 }
531
532 void ShenandoahReferenceProcessor::enqueue_references(bool concurrent) {
533 if (_pending_list == nullptr) {
534 // Nothing to enqueue
535 return;
536 }
537
538 if (!concurrent) {
539 // When called from mark-compact or degen-GC, the locking is done by the VMOperation,
540 enqueue_references_locked();
541 } else {
542 // Heap_lock protects external pending list
543 MonitorLocker ml(Heap_lock);
544
545 enqueue_references_locked();
546
547 // Notify ReferenceHandler thread
548 ml.notify_all();
549 }
550
551 // Reset internal pending list
552 _pending_list = nullptr;
553 _pending_list_tail = &_pending_list;
554 }
555
556 template<typename T>
557 void ShenandoahReferenceProcessor::clean_discovered_list(T* list) {
558 T discovered = *list;
559 while (!CompressedOops::is_null(discovered)) {
560 oop discovered_ref = CompressedOops::decode_not_null(discovered);
561 set_oop_field<T>(list, oop(nullptr));
562 list = reference_discovered_addr<T>(discovered_ref);
563 discovered = *list;
564 }
565 }
566
567 void ShenandoahReferenceProcessor::abandon_partial_discovery() {
568 uint max_workers = ShenandoahHeap::heap()->max_workers();
569 for (uint index = 0; index < max_workers; index++) {
570 if (UseCompressedOops) {
571 clean_discovered_list<narrowOop>(_ref_proc_thread_locals[index].discovered_list_addr<narrowOop>());
572 } else {
573 clean_discovered_list<oop>(_ref_proc_thread_locals[index].discovered_list_addr<oop>());
574 }
575 }
576 if (_pending_list != nullptr) {
577 oop pending = _pending_list;
578 _pending_list = nullptr;
579 if (UseCompressedOops) {
580 narrowOop* list = reference_discovered_addr<narrowOop>(pending);
581 clean_discovered_list<narrowOop>(list);
582 } else {
583 oop* list = reference_discovered_addr<oop>(pending);
584 clean_discovered_list<oop>(list);
585 }
586 }
587 _pending_list_tail = &_pending_list;
588 }
589
590 void ShenandoahReferenceProcessor::collect_statistics() {
591 Counters encountered = {};
592 Counters discovered = {};
593 Counters enqueued = {};
594 uint max_workers = ShenandoahHeap::heap()->max_workers();
595 for (uint i = 0; i < max_workers; i++) {
596 for (size_t type = 0; type < reference_type_count; type++) {
597 encountered[type] += _ref_proc_thread_locals[i].encountered((ReferenceType)type);
598 discovered[type] += _ref_proc_thread_locals[i].discovered((ReferenceType)type);
599 enqueued[type] += _ref_proc_thread_locals[i].enqueued((ReferenceType)type);
600 }
601 }
602
603 _stats = ReferenceProcessorStats(discovered[REF_SOFT],
604 discovered[REF_WEAK],
605 discovered[REF_FINAL],
606 discovered[REF_PHANTOM]);
607
608 log_info(gc,ref)("Encountered references: Soft: " SIZE_FORMAT ", Weak: " SIZE_FORMAT ", Final: " SIZE_FORMAT ", Phantom: " SIZE_FORMAT,
609 encountered[REF_SOFT], encountered[REF_WEAK], encountered[REF_FINAL], encountered[REF_PHANTOM]);
610 log_info(gc,ref)("Discovered references: Soft: " SIZE_FORMAT ", Weak: " SIZE_FORMAT ", Final: " SIZE_FORMAT ", Phantom: " SIZE_FORMAT,
611 discovered[REF_SOFT], discovered[REF_WEAK], discovered[REF_FINAL], discovered[REF_PHANTOM]);
612 log_info(gc,ref)("Enqueued references: Soft: " SIZE_FORMAT ", Weak: " SIZE_FORMAT ", Final: " SIZE_FORMAT ", Phantom: " SIZE_FORMAT,
613 enqueued[REF_SOFT], enqueued[REF_WEAK], enqueued[REF_FINAL], enqueued[REF_PHANTOM]);
614 }