1 /*
2 * Copyright (c) 2017, Google and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26
27 #include "gc/shared/collectedHeap.hpp"
28 #include "memory/universe.hpp"
29 #include "runtime/heapMonitoring.hpp"
30 #include "runtime/vframe.hpp"
31
32 static const int MaxStackDepth = 1024;
33
34 // Internal data structure representing traces.
35 struct StackTraceData : CHeapObj<mtInternal> {
36 jvmtiStackTrace *trace;
37 oop obj;
38 int references;
39
40 StackTraceData(jvmtiStackTrace *t, oop o) : trace(t), obj(o), references(0) {}
41
42 StackTraceData() : trace(NULL), obj(NULL), references(0) {}
43
44 // StackTraceDatas are shared around the board between various lists. So
45 // handle this by hand instead of having this in the destructor. There are
46 // cases where the struct is on the stack but holding heap data not to be
47 // freed.
48 static void free_data(StackTraceData *data) {
49 if (data->trace != NULL) {
50 FREE_C_HEAP_ARRAY(jvmtiFrameInfo, data->trace->frames);
51 FREE_C_HEAP_OBJ(data->trace);
52 }
53 delete data;
54 }
55 };
56
57 // Fixed size buffer for holding garbage traces.
58 class GarbageTracesBuffer : public CHeapObj<mtInternal> {
59 public:
60 GarbageTracesBuffer(uint32_t size) : _size(size) {
61 _garbage_traces = NEW_C_HEAP_ARRAY(StackTraceData*,
62 size,
63 mtInternal);
64 memset(_garbage_traces, 0, sizeof(StackTraceData*) * size);
65 }
66
67 virtual ~GarbageTracesBuffer() {
68 FREE_C_HEAP_ARRAY(StackTraceData*, _garbage_traces);
69 }
70
71 StackTraceData** get_traces() const {
72 return _garbage_traces;
73 }
74
75 bool store_trace(StackTraceData *trace) {
76 uint32_t index;
77 if (!select_replacement(&index)) {
78 return false;
79 }
80
81 StackTraceData *old_data = _garbage_traces[index];
82
83 if (old_data != NULL) {
84 old_data->references--;
85
86 if (old_data->references == 0) {
87 StackTraceData::free_data(old_data);
88 }
89 }
90
91 trace->references++;
92 _garbage_traces[index] = trace;
93 return true;
94 }
95
96 uint32_t size() const {
97 return _size;
98 }
99
100 protected:
101 // Subclasses select the trace to replace. Returns false if no replacement
102 // is to happen, otherwise stores the index of the trace to replace in
103 // *index.
104 virtual bool select_replacement(uint32_t *index) = 0;
105
106 const uint32_t _size;
107
108 private:
109 // The current garbage traces. A fixed-size ring buffer.
110 StackTraceData **_garbage_traces;
111 };
112
113 // Keep statistical sample of traces over the lifetime of the server.
114 // When the buffer is full, replace a random entry with probability
115 // 1/samples_seen. This strategy tends towards preserving the most frequently
116 // occuring traces over time.
117 class FrequentGarbageTraces : public GarbageTracesBuffer {
118 public:
119 FrequentGarbageTraces(int size)
120 : GarbageTracesBuffer(size),
121 _garbage_traces_pos(0),
122 _samples_seen(0) {
123 }
124
125 virtual ~FrequentGarbageTraces() {
126 }
127
128 virtual bool select_replacement(uint32_t* index) {
129 ++_samples_seen;
130
131 if (_garbage_traces_pos < _size) {
132 *index = _garbage_traces_pos++;
133 return true;
134 }
135
136 uint64_t random_uint64 =
137 (static_cast<uint64_t>(::random()) << 32) | ::random();
138
139 uint32_t random_index = random_uint64 % _samples_seen;
140 if (random_index < _size) {
141 *index = random_index;
142 return true;
143 }
144
145 return false;
146 }
147
148 private:
149 // The current position in the buffer as we initially fill it.
150 uint32_t _garbage_traces_pos;
151
152 uint64_t _samples_seen;
153 };
154
155 // Store most recent garbage traces.
156 class MostRecentGarbageTraces : public GarbageTracesBuffer {
157 public:
158 MostRecentGarbageTraces(int size)
159 : GarbageTracesBuffer(size),
160 _garbage_traces_pos(0) {
161 }
162
163 virtual ~MostRecentGarbageTraces() {
164 }
165
166 virtual bool select_replacement(uint32_t* index) {
167 *index = _garbage_traces_pos;
168
169 _garbage_traces_pos =
170 (_garbage_traces_pos + 1) % _size;
171
172 return true;
173 }
174
175 private:
176 // The current position in the buffer.
177 uint32_t _garbage_traces_pos;
178 };
179
180 // Each object that we profile is stored as trace with the thread_id.
181 class StackTraceStorage : public CHeapObj<mtInternal> {
182 public:
183 // The function that gets called to add a trace to the list of
184 // traces we are maintaining.
185 void add_trace(jvmtiStackTrace *trace, oop o);
186
187 // The function that gets called by the client to retrieve the list
188 // of stack traces. Passes a jvmtiStackTraces which will get mutated.
189 void get_all_stack_traces(jvmtiStackTraces *traces);
190
191 // The function that gets called by the client to retrieve the list
192 // of stack traces. Passes a jvmtiStackTraces which will get mutated.
193 void get_garbage_stack_traces(jvmtiStackTraces *traces);
194
195 // The function that gets called by the client to retrieve the list
196 // of stack traces. Passes a jvmtiStackTraces which will get mutated.
197 void get_frequent_garbage_stack_traces(jvmtiStackTraces *traces);
198
199 // Executes whenever weak references are traversed. is_alive tells
200 // you if the given oop is still reachable and live.
201 size_t weak_oops_do(BoolObjectClosure* is_alive, OopClosure *f);
202
203 ~StackTraceStorage();
204 StackTraceStorage();
205
206 static StackTraceStorage* storage() {
207 static StackTraceStorage internal_storage;
208 return &internal_storage;
209 }
210
211 void initialize(int max_storage) {
212 MutexLocker mu(HeapMonitor_lock);
213 free_storage();
214 allocate_storage(max_storage);
215 memset(&_stats, 0, sizeof(_stats));
216 }
217
218 const jvmtiHeapSamplingStats& get_heap_sampling_stats() const {
219 return _stats;
220 }
221
222 void accumulate_sample_rate(size_t rate) {
223 _stats.sample_rate_accumulation += rate;
224 _stats.sample_rate_count++;
225 }
226
227 bool initialized() { return _initialized; }
228 volatile bool *initialized_address() { return &_initialized; }
229
230 private:
231 // Protects the traces currently sampled (below).
232 volatile intptr_t _stack_storage_lock[1];
233
234 // The traces currently sampled.
235 GrowableArray<StackTraceData> *_allocated_traces;
236
237 // Recent garbage traces.
238 MostRecentGarbageTraces *_recent_garbage_traces;
239
240 // Frequent garbage traces.
241 FrequentGarbageTraces *_frequent_garbage_traces;
242
243 // Heap Sampling statistics.
244 jvmtiHeapSamplingStats _stats;
245
246 // Maximum amount of storage provided by the JVMTI call initialize_profiling.
247 int _max_gc_storage;
248
249 static StackTraceStorage* internal_storage;
250 volatile bool _initialized;
251
252 // Support functions and classes for copying data to the external
253 // world.
254 class StackTraceDataCopier {
255 public:
256 virtual int size() const = 0;
257 virtual const StackTraceData *get(uint32_t i) const = 0;
258 };
259
260 class LiveStackTraceDataCopier : public StackTraceDataCopier {
261 public:
262 LiveStackTraceDataCopier(GrowableArray<StackTraceData> *data) :
263 _data(data) {}
264 int size() const { return _data ? _data->length() : 0; }
265 const StackTraceData *get(uint32_t i) const { return _data->adr_at(i); }
266
267 private:
268 GrowableArray<StackTraceData> *_data;
269 };
270
271 class GarbageStackTraceDataCopier : public StackTraceDataCopier {
272 public:
273 GarbageStackTraceDataCopier(StackTraceData **data, int size) :
274 _data(data), _size(size) {}
275 int size() const { return _size; }
276 const StackTraceData *get(uint32_t i) const { return _data[i]; }
277
278 private:
279 StackTraceData **_data;
280 int _size;
281 };
282
283 // Copies from StackTraceData to jvmtiStackTrace.
284 bool deep_copy(jvmtiStackTrace *to, const StackTraceData *from);
285
286 // Creates a deep copy of the list of StackTraceData.
287 void copy_stack_traces(const StackTraceDataCopier &copier,
288 jvmtiStackTraces *traces);
289
290 void store_garbage_trace(const StackTraceData &trace);
291
292 void free_garbage();
293 void free_storage();
294 void allocate_storage(int max_gc_storage);
295 };
296
297 StackTraceStorage* StackTraceStorage::internal_storage;
298
299 // Statics for Sampler
300 double HeapMonitoring::_log_table[1 << FastLogNumBits];
301 bool HeapMonitoring::_enabled;
302 AlwaysTrueClosure HeapMonitoring::_always_true;
303 jint HeapMonitoring::_monitoring_rate;
304
305 // Cheap random number generator
306 uint64_t HeapMonitoring::_rnd;
307
308 StackTraceStorage::StackTraceStorage() :
309 _allocated_traces(NULL),
310 _recent_garbage_traces(NULL),
311 _frequent_garbage_traces(NULL),
312 _max_gc_storage(0),
313 _initialized(false) {
314 _stack_storage_lock[0] = 0;
315 }
316
317 void StackTraceStorage::free_garbage() {
318 StackTraceData **recent_garbage = NULL;
319 uint32_t recent_size = 0;
320
321 StackTraceData **frequent_garbage = NULL;
322 uint32_t frequent_size = 0;
323
324 if (_recent_garbage_traces != NULL) {
325 recent_garbage = _recent_garbage_traces->get_traces();
326 recent_size = _recent_garbage_traces->size();
327 }
328
329 if (_frequent_garbage_traces != NULL) {
330 frequent_garbage = _frequent_garbage_traces->get_traces();
331 frequent_size = _frequent_garbage_traces->size();
332 }
333
334 // Simple solution since this happens at exit.
335 // Go through the recent and remove any that only are referenced there.
336 for (uint32_t i = 0; i < recent_size; i++) {
337 StackTraceData *trace = recent_garbage[i];
338 if (trace != NULL) {
339 trace->references--;
340
341 if (trace->references == 0) {
342 StackTraceData::free_data(trace);
343 }
344 }
345 }
346
347 // Then go through the frequent and remove those that are now only there.
348 for (uint32_t i = 0; i < frequent_size; i++) {
349 StackTraceData *trace = frequent_garbage[i];
350 if (trace != NULL) {
351 trace->references--;
352
353 if (trace->references == 0) {
354 StackTraceData::free_data(trace);
355 }
356 }
357 }
358 }
359
360 void StackTraceStorage::free_storage() {
361 delete _allocated_traces;
362
363 free_garbage();
364 delete _recent_garbage_traces;
365 delete _frequent_garbage_traces;
366 _initialized = false;
367 }
368
369 StackTraceStorage::~StackTraceStorage() {
370 free_storage();
371 }
372
373 void StackTraceStorage::allocate_storage(int max_gc_storage) {
374 // In case multiple threads got locked and then 1 by 1 got through.
375 if (_initialized) {
376 return;
377 }
378
379 _allocated_traces = new (ResourceObj::C_HEAP, mtInternal)
380 GrowableArray<StackTraceData>(128, true);
381
382 _recent_garbage_traces = new MostRecentGarbageTraces(max_gc_storage);
383 _frequent_garbage_traces = new FrequentGarbageTraces(max_gc_storage);
384
385 _max_gc_storage = max_gc_storage;
386 _initialized = true;
387 }
388
389 void StackTraceStorage::add_trace(jvmtiStackTrace *trace, oop o) {
390 MutexLocker mu(HeapMonitor_lock);
391 StackTraceData new_data(trace, o);
392 _stats.sample_count++;
393 _stats.stack_depth_accumulation += trace->frame_count;
394 _allocated_traces->append(new_data);
395 }
396
397 size_t StackTraceStorage::weak_oops_do(BoolObjectClosure *is_alive,
398 OopClosure *f) {
399 MutexLocker mu(HeapMonitor_lock);
400 size_t count = 0;
401 if (initialized()) {
402 int len = _allocated_traces->length();
403
404 // Compact the oop traces. Moves the live oops to the beginning of the
405 // growable array, potentially overwriting the dead ones.
406 int curr_pos = 0;
407 for (int i = 0; i < len; i++) {
408 StackTraceData &trace = _allocated_traces->at(i);
409 oop value = trace.obj;
410 if (Universe::heap()->is_in_reserved(value)
411 && is_alive->do_object_b(value)) {
412 // Update the oop to point to the new object if it is still alive.
413 f->do_oop(&(trace.obj));
414
415 // Copy the old trace, if it is still live.
416 _allocated_traces->at_put(curr_pos++, trace);
417
418 count++;
419 } else {
420 // If the old trace is no longer live, add it to the list of
421 // recently collected garbage.
422 store_garbage_trace(trace);
423 }
424 }
425
426 // Zero out remaining array elements. Even though the call to trunc_to
427 // below truncates these values, zeroing them out is good practice.
428 StackTraceData zero_trace;
429 for (int i = curr_pos; i < len; i++) {
430 _allocated_traces->at_put(i, zero_trace);
431 }
432
433 // Set the array's length to the number of live elements.
434 _allocated_traces->trunc_to(curr_pos);
435 }
436
437 return count;
438 }
439
440 bool StackTraceStorage::deep_copy(jvmtiStackTrace *to,
441 const StackTraceData *from) {
442 const jvmtiStackTrace *src = from->trace;
443 *to = *src;
444
445 to->frames =
446 NEW_C_HEAP_ARRAY(jvmtiFrameInfo, src->frame_count, mtInternal);
447
448 if (to->frames == NULL) {
449 return false;
450 }
451
452 memcpy(to->frames,
453 src->frames,
454 sizeof(jvmtiFrameInfo) * src->frame_count);
455 return true;
456 }
457
458 // Called by the outside world; returns a copy of the stack traces
459 // (because we could be replacing them as the user handles them).
460 // The array is secretly null-terminated (to make it easier to reclaim).
461 void StackTraceStorage::get_all_stack_traces(jvmtiStackTraces *traces) {
462 LiveStackTraceDataCopier copier(_allocated_traces);
463 copy_stack_traces(copier, traces);
464 }
465
466 // See comment on get_all_stack_traces
467 void StackTraceStorage::get_garbage_stack_traces(jvmtiStackTraces *traces) {
468 GarbageStackTraceDataCopier copier(_recent_garbage_traces->get_traces(),
469 _recent_garbage_traces->size());
470 copy_stack_traces(copier, traces);
471 }
472
473 // See comment on get_all_stack_traces
474 void StackTraceStorage::get_frequent_garbage_stack_traces(
475 jvmtiStackTraces *traces) {
476 GarbageStackTraceDataCopier copier(_frequent_garbage_traces->get_traces(),
477 _frequent_garbage_traces->size());
478 copy_stack_traces(copier, traces);
479 }
480
481
482 void StackTraceStorage::copy_stack_traces(const StackTraceDataCopier &copier,
483 jvmtiStackTraces *traces) {
484 MutexLocker mu(HeapMonitor_lock);
485 int len = copier.size();
486
487 // Create a new array to store the StackTraceData objects.
488 // + 1 for a NULL at the end.
489 jvmtiStackTrace *t =
490 NEW_C_HEAP_ARRAY(jvmtiStackTrace, len + 1, mtInternal);
491 if (t == NULL) {
492 traces->stack_traces = NULL;
493 traces->trace_count = 0;
494 return;
495 }
496 // +1 to have a NULL at the end of the array.
497 memset(t, 0, (len + 1) * sizeof(*t));
498
499 // Copy the StackTraceData objects into the new array.
500 int trace_count = 0;
501 for (int i = 0; i < len; i++) {
502 const StackTraceData *stack_trace = copier.get(i);
503 if (stack_trace != NULL) {
504 jvmtiStackTrace *to = &t[trace_count];
505 if (!deep_copy(to, stack_trace)) {
506 continue;
507 }
508 trace_count++;
509 }
510 }
511
512 traces->stack_traces = t;
513 traces->trace_count = trace_count;
514 }
515
516 void StackTraceStorage::store_garbage_trace(const StackTraceData &trace) {
517 StackTraceData *new_trace = new StackTraceData();
518 *new_trace = trace;
519
520 bool accepted = _recent_garbage_traces->store_trace(new_trace);
521
522 // Accepted is on the right of the boolean to force the store_trace to happen.
523 accepted = _frequent_garbage_traces->store_trace(new_trace) || accepted;
524
525 if (!accepted) {
526 // No one wanted to use it.
527 delete new_trace;
528 }
529
530 _stats.garbage_collected_samples++;
531 }
532
533 // Delegate the initialization question to the underlying storage system.
534 bool HeapMonitoring::initialized() {
535 return StackTraceStorage::storage()->initialized();
536 }
537
538 // Delegate the initialization question to the underlying storage system.
539 bool *HeapMonitoring::initialized_address() {
540 return
541 const_cast<bool*>(StackTraceStorage::storage()->initialized_address());
542 }
543
544 void HeapMonitoring::get_live_traces(jvmtiStackTraces *traces) {
545 StackTraceStorage::storage()->get_all_stack_traces(traces);
546 }
547
548 void HeapMonitoring::get_sampling_statistics(jvmtiHeapSamplingStats *stats) {
549 const jvmtiHeapSamplingStats& internal_stats =
550 StackTraceStorage::storage()->get_heap_sampling_stats();
551 *stats = internal_stats;
552 }
553
554 void HeapMonitoring::get_frequent_garbage_traces(jvmtiStackTraces *traces) {
555 StackTraceStorage::storage()->get_frequent_garbage_stack_traces(traces);
556 }
557
558 void HeapMonitoring::get_garbage_traces(jvmtiStackTraces *traces) {
559 StackTraceStorage::storage()->get_garbage_stack_traces(traces);
560 }
561
562 void HeapMonitoring::release_traces(jvmtiStackTraces *traces) {
563 jint trace_count = traces->trace_count;
564 jvmtiStackTrace *stack_traces = traces->stack_traces;
565
566 for (jint i = 0; i < trace_count; i++) {
567 jvmtiStackTrace *current_trace = stack_traces + i;
568 FREE_C_HEAP_ARRAY(jvmtiFrameInfo, current_trace->frames);
569 }
570
571 FREE_C_HEAP_ARRAY(jvmtiStackTrace, traces->stack_traces);
572 traces->trace_count = 0;
573 traces->stack_traces = NULL;
574 }
575
576 // Invoked by the GC to clean up old stack traces and remove old arrays
577 // of instrumentation that are still lying around.
578 size_t HeapMonitoring::weak_oops_do(BoolObjectClosure* is_alive,
579 OopClosure *f) {
580 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
581 return StackTraceStorage::storage()->weak_oops_do(is_alive, f);
582 }
583
584 void HeapMonitoring::initialize_profiling(jint monitoring_rate,
585 jint max_gc_storage) {
586 // Ignore if already enabled.
587 if (_enabled) {
588 return;
589 }
590
591 _monitoring_rate = monitoring_rate;
592
593 // Populate the lookup table for fast_log2.
594 // This approximates the log2 curve with a step function.
595 // Steps have height equal to log2 of the mid-point of the step.
596 for (int i = 0; i < (1 << FastLogNumBits); i++) {
597 double half_way = static_cast<double>(i + 0.5);
598 _log_table[i] = (log(1.0 + half_way / (1 << FastLogNumBits)) / log(2.0));
599 }
600
601 JavaThread *t = static_cast<JavaThread *>(Thread::current());
602 _rnd = static_cast<uint32_t>(reinterpret_cast<uintptr_t>(t));
603 if (_rnd == 0) {
604 _rnd = 1;
605 }
606
607 StackTraceStorage::storage()->initialize(max_gc_storage);
608 _enabled = true;
609 }
610
611 void HeapMonitoring::stop_profiling() {
612 _enabled = false;
613 }
614
615 // Generates a geometric variable with the specified mean (512K by default).
616 // This is done by generating a random number between 0 and 1 and applying
617 // the inverse cumulative distribution function for an exponential.
618 // Specifically: Let m be the inverse of the sample rate, then
619 // the probability distribution function is m*exp(-mx) so the CDF is
620 // p = 1 - exp(-mx), so
621 // q = 1 - p = exp(-mx)
622 // log_e(q) = -mx
623 // -log_e(q)/m = x
624 // log_2(q) * (-log_e(2) * 1/m) = x
625 // In the code, q is actually in the range 1 to 2**26, hence the -26 below
626 void HeapMonitoring::pick_next_sample(size_t *ptr) {
627 _rnd = next_random(_rnd);
628 // Take the top 26 bits as the random number
629 // (This plus a 1<<58 sampling bound gives a max possible step of
630 // 5194297183973780480 bytes. In this case,
631 // for sample_parameter = 1<<19, max possible step is
632 // 9448372 bytes (24 bits).
633 const uint64_t prng_mod_power = 48; // Number of bits in prng
634 // The uint32_t cast is to prevent a (hard-to-reproduce) NAN
635 // under piii debug for some binaries.
636 double q = static_cast<uint32_t>(_rnd >> (prng_mod_power - 26)) + 1.0;
637 // Put the computed p-value through the CDF of a geometric.
638 // For faster performance (save ~1/20th exec time), replace
639 // min(0.0, FastLog2(q) - 26) by (Fastlog2(q) - 26.000705)
640 // The value 26.000705 is used rather than 26 to compensate
641 // for inaccuracies in FastLog2 which otherwise result in a
642 // negative answer.
643 double log_val = (fast_log2(q) - 26);
644 size_t rate = static_cast<size_t>(
645 (0.0 < log_val ? 0.0 : log_val) * (-log(2.0) * (_monitoring_rate)) + 1);
646 *ptr = rate;
647
648 StackTraceStorage::storage()->accumulate_sample_rate(rate);
649 }
650
651 void HeapMonitoring::object_alloc_do_sample(Thread *t, oopDesc *o, intx byte_size) {
652 #if defined(X86) || defined(PPC)
653 JavaThread *thread = static_cast<JavaThread *>(t);
654 if (StackTraceStorage::storage()->initialized()) {
655 assert(t->is_Java_thread(), "non-Java thread passed to do_sample");
656 JavaThread *thread = static_cast<JavaThread *>(t);
657
658 jvmtiStackTrace *trace = NEW_C_HEAP_OBJ(jvmtiStackTrace, mtInternal);
659 if (trace == NULL) {
660 return;
661 }
662
663 jvmtiFrameInfo *frames =
664 NEW_C_HEAP_ARRAY(jvmtiFrameInfo, MaxStackDepth, mtInternal);
665
666 if (frames == NULL) {
667 FREE_C_HEAP_OBJ(trace);
668 return;
669 }
670
671 trace->frames = frames;
672 trace->thread_id = SharedRuntime::get_java_tid(thread);
673 trace->size = byte_size;
674 trace->frame_count = 0;
675
676 if (thread->has_last_Java_frame()) { // just to be safe
677 vframeStream vfst(thread, true);
678 int count = 0;
679 while (!vfst.at_end() && count < MaxStackDepth) {
680 Method* m = vfst.method();
681 frames[count].location = vfst.bci();
682 frames[count].method = m->jmethod_id();
683 count++;
684
685 vfst.next();
686 }
687 trace->frame_count = count;
688 }
689
690 if (trace->frame_count> 0) {
691 // Success!
692 StackTraceStorage::storage()->add_trace(trace, o);
693 return;
694 }
695
696 // Failure!
697 FREE_C_HEAP_ARRAY(jvmtiFrameInfo, trace->frames);
698 FREE_C_HEAP_OBJ(trace);
699 }
700 #else
701 Unimplemented();
702 #endif
703 }