1 /*
2 * Copyright (c) 2003, 2020, 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 #include "precompiled.hpp"
26 #include "classfile/classLoaderDataGraph.hpp"
27 #include "classfile/moduleEntry.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "jvmtifiles/jvmtiEnv.hpp"
30 #include "memory/iterator.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "oops/objArrayKlass.hpp"
33 #include "oops/objArrayOop.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "oops/oopHandle.inline.hpp"
36 #include "prims/jvmtiEnvBase.hpp"
37 #include "prims/jvmtiEventController.inline.hpp"
38 #include "prims/jvmtiExtensions.hpp"
39 #include "prims/jvmtiImpl.hpp"
40 #include "prims/jvmtiManageCapabilities.hpp"
41 #include "prims/jvmtiTagMap.hpp"
42 #include "prims/jvmtiThreadState.inline.hpp"
43 #include "runtime/biasedLocking.hpp"
44 #include "runtime/deoptimization.hpp"
45 #include "runtime/frame.inline.hpp"
46 #include "runtime/handles.inline.hpp"
47 #include "runtime/interfaceSupport.inline.hpp"
48 #include "runtime/jfieldIDWorkaround.hpp"
49 #include "runtime/jniHandles.inline.hpp"
50 #include "runtime/objectMonitor.hpp"
51 #include "runtime/objectMonitor.inline.hpp"
52 #include "runtime/signature.hpp"
53 #include "runtime/thread.inline.hpp"
54 #include "runtime/threadSMR.hpp"
55 #include "runtime/vframe.hpp"
56 #include "runtime/vframe_hp.hpp"
57 #include "runtime/vmThread.hpp"
58 #include "runtime/vmOperations.hpp"
59
60 ///////////////////////////////////////////////////////////////
61 //
62 // JvmtiEnvBase
63 //
64
65 JvmtiEnvBase* JvmtiEnvBase::_head_environment = NULL;
66
67 bool JvmtiEnvBase::_globally_initialized = false;
68 volatile bool JvmtiEnvBase::_needs_clean_up = false;
69
70 jvmtiPhase JvmtiEnvBase::_phase = JVMTI_PHASE_PRIMORDIAL;
71
72 volatile int JvmtiEnvBase::_dying_thread_env_iteration_count = 0;
73
74 extern jvmtiInterface_1_ jvmti_Interface;
75 extern jvmtiInterface_1_ jvmtiTrace_Interface;
76
77
78 // perform initializations that must occur before any JVMTI environments
79 // are released but which should only be initialized once (no matter
80 // how many environments are created).
81 void
82 JvmtiEnvBase::globally_initialize() {
83 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
84 assert(_globally_initialized == false, "bad call");
85
86 JvmtiManageCapabilities::initialize();
87
88 // register extension functions and events
89 JvmtiExtensions::register_extensions();
90
91 #ifdef JVMTI_TRACE
92 JvmtiTrace::initialize();
93 #endif
94
95 _globally_initialized = true;
96 }
97
98
99 void
100 JvmtiEnvBase::initialize() {
101 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
102
103 // Add this environment to the end of the environment list (order is important)
104 {
105 // This block of code must not contain any safepoints, as list deallocation
106 // (which occurs at a safepoint) cannot occur simultaneously with this list
107 // addition. Note: NoSafepointVerifier cannot, currently, be used before
108 // threads exist.
109 JvmtiEnvIterator it;
110 JvmtiEnvBase *previous_env = NULL;
111 for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
112 previous_env = env;
113 }
114 if (previous_env == NULL) {
115 _head_environment = this;
116 } else {
117 previous_env->set_next_environment(this);
118 }
119 }
120
121 if (_globally_initialized == false) {
122 globally_initialize();
123 }
124 }
125
126 jvmtiPhase
127 JvmtiEnvBase::phase() {
128 // For the JVMTI environments possessed the can_generate_early_vmstart:
129 // replace JVMTI_PHASE_PRIMORDIAL with JVMTI_PHASE_START
130 if (_phase == JVMTI_PHASE_PRIMORDIAL &&
131 JvmtiExport::early_vmstart_recorded() &&
132 early_vmstart_env()) {
133 return JVMTI_PHASE_START;
134 }
135 return _phase; // Normal case
136 }
137
138 bool
139 JvmtiEnvBase::is_valid() {
140 jint value = 0;
141
142 // This object might not be a JvmtiEnvBase so we can't assume
143 // the _magic field is properly aligned. Get the value in a safe
144 // way and then check against JVMTI_MAGIC.
145
146 switch (sizeof(_magic)) {
147 case 2:
148 value = Bytes::get_native_u2((address)&_magic);
149 break;
150
151 case 4:
152 value = Bytes::get_native_u4((address)&_magic);
153 break;
154
155 case 8:
156 value = Bytes::get_native_u8((address)&_magic);
157 break;
158
159 default:
160 guarantee(false, "_magic field is an unexpected size");
161 }
162
163 return value == JVMTI_MAGIC;
164 }
165
166
167 bool
168 JvmtiEnvBase::use_version_1_0_semantics() {
169 int major, minor, micro;
170
171 JvmtiExport::decode_version_values(_version, &major, &minor, µ);
172 return major == 1 && minor == 0; // micro version doesn't matter here
173 }
174
175
176 bool
177 JvmtiEnvBase::use_version_1_1_semantics() {
178 int major, minor, micro;
179
180 JvmtiExport::decode_version_values(_version, &major, &minor, µ);
181 return major == 1 && minor == 1; // micro version doesn't matter here
182 }
183
184 bool
185 JvmtiEnvBase::use_version_1_2_semantics() {
186 int major, minor, micro;
187
188 JvmtiExport::decode_version_values(_version, &major, &minor, µ);
189 return major == 1 && minor == 2; // micro version doesn't matter here
190 }
191
192
193 JvmtiEnvBase::JvmtiEnvBase(jint version) : _env_event_enable() {
194 _version = version;
195 _env_local_storage = NULL;
196 _tag_map = NULL;
197 _native_method_prefix_count = 0;
198 _native_method_prefixes = NULL;
199 _next = NULL;
200 _class_file_load_hook_ever_enabled = false;
201
202 // Moot since ClassFileLoadHook not yet enabled.
203 // But "true" will give a more predictable ClassFileLoadHook behavior
204 // for environment creation during ClassFileLoadHook.
205 _is_retransformable = true;
206
207 // all callbacks initially NULL
208 memset(&_event_callbacks,0,sizeof(jvmtiEventCallbacks));
209
210 // all capabilities initially off
211 memset(&_current_capabilities, 0, sizeof(_current_capabilities));
212
213 // all prohibited capabilities initially off
214 memset(&_prohibited_capabilities, 0, sizeof(_prohibited_capabilities));
215
216 _magic = JVMTI_MAGIC;
217
218 JvmtiEventController::env_initialize((JvmtiEnv*)this);
219
220 #ifdef JVMTI_TRACE
221 _jvmti_external.functions = TraceJVMTI != NULL ? &jvmtiTrace_Interface : &jvmti_Interface;
222 #else
223 _jvmti_external.functions = &jvmti_Interface;
224 #endif
225 }
226
227
228 void
229 JvmtiEnvBase::dispose() {
230
231 #ifdef JVMTI_TRACE
232 JvmtiTrace::shutdown();
233 #endif
234
235 // Dispose of event info and let the event controller call us back
236 // in a locked state (env_dispose, below)
237 JvmtiEventController::env_dispose(this);
238 }
239
240 void
241 JvmtiEnvBase::env_dispose() {
242 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
243
244 // We have been entered with all events disabled on this environment.
245 // A race to re-enable events (by setting callbacks) is prevented by
246 // checking for a valid environment when setting callbacks (while
247 // holding the JvmtiThreadState_lock).
248
249 // Mark as invalid.
250 _magic = DISPOSED_MAGIC;
251
252 // Relinquish all capabilities.
253 jvmtiCapabilities *caps = get_capabilities();
254 JvmtiManageCapabilities::relinquish_capabilities(caps, caps, caps);
255
256 // Same situation as with events (see above)
257 set_native_method_prefixes(0, NULL);
258
259 JvmtiTagMap* tag_map_to_deallocate = _tag_map;
260 set_tag_map(NULL);
261 // A tag map can be big, deallocate it now
262 if (tag_map_to_deallocate != NULL) {
263 delete tag_map_to_deallocate;
264 }
265
266 _needs_clean_up = true;
267 }
268
269
270 JvmtiEnvBase::~JvmtiEnvBase() {
271 assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
272
273 // There is a small window of time during which the tag map of a
274 // disposed environment could have been reallocated.
275 // Make sure it is gone.
276 JvmtiTagMap* tag_map_to_deallocate = _tag_map;
277 set_tag_map(NULL);
278 // A tag map can be big, deallocate it now
279 if (tag_map_to_deallocate != NULL) {
280 delete tag_map_to_deallocate;
281 }
282
283 _magic = BAD_MAGIC;
284 }
285
286
287 void
288 JvmtiEnvBase::periodic_clean_up() {
289 assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
290
291 // JvmtiEnvBase reference is saved in JvmtiEnvThreadState. So
292 // clean up JvmtiThreadState before deleting JvmtiEnv pointer.
293 JvmtiThreadState::periodic_clean_up();
294
295 // Unlink all invalid environments from the list of environments
296 // and deallocate them
297 JvmtiEnvIterator it;
298 JvmtiEnvBase* previous_env = NULL;
299 JvmtiEnvBase* env = it.first();
300 while (env != NULL) {
301 if (env->is_valid()) {
302 previous_env = env;
303 env = it.next(env);
304 } else {
305 // This one isn't valid, remove it from the list and deallocate it
306 JvmtiEnvBase* defunct_env = env;
307 env = it.next(env);
308 if (previous_env == NULL) {
309 _head_environment = env;
310 } else {
311 previous_env->set_next_environment(env);
312 }
313 delete defunct_env;
314 }
315 }
316
317 }
318
319
320 void
321 JvmtiEnvBase::check_for_periodic_clean_up() {
322 assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
323
324 class ThreadInsideIterationClosure: public ThreadClosure {
325 private:
326 bool _inside;
327 public:
328 ThreadInsideIterationClosure() : _inside(false) {};
329
330 void do_thread(Thread* thread) {
331 _inside |= thread->is_inside_jvmti_env_iteration();
332 }
333
334 bool is_inside_jvmti_env_iteration() {
335 return _inside;
336 }
337 };
338
339 if (_needs_clean_up) {
340 // Check if we are currently iterating environment,
341 // deallocation should not occur if we are
342 ThreadInsideIterationClosure tiic;
343 Threads::threads_do(&tiic);
344 if (!tiic.is_inside_jvmti_env_iteration() &&
345 !is_inside_dying_thread_env_iteration()) {
346 _needs_clean_up = false;
347 JvmtiEnvBase::periodic_clean_up();
348 }
349 }
350 }
351
352
353 void
354 JvmtiEnvBase::record_first_time_class_file_load_hook_enabled() {
355 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(),
356 "sanity check");
357
358 if (!_class_file_load_hook_ever_enabled) {
359 _class_file_load_hook_ever_enabled = true;
360
361 if (get_capabilities()->can_retransform_classes) {
362 _is_retransformable = true;
363 } else {
364 _is_retransformable = false;
365
366 // cannot add retransform capability after ClassFileLoadHook has been enabled
367 get_prohibited_capabilities()->can_retransform_classes = 1;
368 }
369 }
370 }
371
372
373 void
374 JvmtiEnvBase::record_class_file_load_hook_enabled() {
375 if (!_class_file_load_hook_ever_enabled) {
376 if (Threads::number_of_threads() == 0) {
377 record_first_time_class_file_load_hook_enabled();
378 } else {
379 MutexLocker mu(JvmtiThreadState_lock);
380 record_first_time_class_file_load_hook_enabled();
381 }
382 }
383 }
384
385
386 jvmtiError
387 JvmtiEnvBase::set_native_method_prefixes(jint prefix_count, char** prefixes) {
388 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(),
389 "sanity check");
390
391 int old_prefix_count = get_native_method_prefix_count();
392 char **old_prefixes = get_native_method_prefixes();
393
394 // allocate and install the new prefixex
395 if (prefix_count == 0 || !is_valid()) {
396 _native_method_prefix_count = 0;
397 _native_method_prefixes = NULL;
398 } else {
399 // there are prefixes, allocate an array to hold them, and fill it
400 char** new_prefixes = (char**)os::malloc((prefix_count) * sizeof(char*), mtInternal);
401 if (new_prefixes == NULL) {
402 return JVMTI_ERROR_OUT_OF_MEMORY;
403 }
404 for (int i = 0; i < prefix_count; i++) {
405 char* prefix = prefixes[i];
406 if (prefix == NULL) {
407 for (int j = 0; j < (i-1); j++) {
408 os::free(new_prefixes[j]);
409 }
410 os::free(new_prefixes);
411 return JVMTI_ERROR_NULL_POINTER;
412 }
413 prefix = os::strdup(prefixes[i]);
414 if (prefix == NULL) {
415 for (int j = 0; j < (i-1); j++) {
416 os::free(new_prefixes[j]);
417 }
418 os::free(new_prefixes);
419 return JVMTI_ERROR_OUT_OF_MEMORY;
420 }
421 new_prefixes[i] = prefix;
422 }
423 _native_method_prefix_count = prefix_count;
424 _native_method_prefixes = new_prefixes;
425 }
426
427 // now that we know the new prefixes have been successfully installed we can
428 // safely remove the old ones
429 if (old_prefix_count != 0) {
430 for (int i = 0; i < old_prefix_count; i++) {
431 os::free(old_prefixes[i]);
432 }
433 os::free(old_prefixes);
434 }
435
436 return JVMTI_ERROR_NONE;
437 }
438
439
440 // Collect all the prefixes which have been set in any JVM TI environments
441 // by the SetNativeMethodPrefix(es) functions. Be sure to maintain the
442 // order of environments and the order of prefixes within each environment.
443 // Return in a resource allocated array.
444 char**
445 JvmtiEnvBase::get_all_native_method_prefixes(int* count_ptr) {
446 assert(Threads::number_of_threads() == 0 ||
447 SafepointSynchronize::is_at_safepoint() ||
448 JvmtiThreadState_lock->is_locked(),
449 "sanity check");
450
451 int total_count = 0;
452 GrowableArray<char*>* prefix_array =new GrowableArray<char*>(5);
453
454 JvmtiEnvIterator it;
455 for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
456 int prefix_count = env->get_native_method_prefix_count();
457 char** prefixes = env->get_native_method_prefixes();
458 for (int j = 0; j < prefix_count; j++) {
459 // retrieve a prefix and so that it is safe against asynchronous changes
460 // copy it into the resource area
461 char* prefix = prefixes[j];
462 char* prefix_copy = NEW_RESOURCE_ARRAY(char, strlen(prefix)+1);
463 strcpy(prefix_copy, prefix);
464 prefix_array->at_put_grow(total_count++, prefix_copy);
465 }
466 }
467
468 char** all_prefixes = NEW_RESOURCE_ARRAY(char*, total_count);
469 char** p = all_prefixes;
470 for (int i = 0; i < total_count; ++i) {
471 *p++ = prefix_array->at(i);
472 }
473 *count_ptr = total_count;
474 return all_prefixes;
475 }
476
477 void
478 JvmtiEnvBase::set_event_callbacks(const jvmtiEventCallbacks* callbacks,
479 jint size_of_callbacks) {
480 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
481
482 size_t byte_cnt = sizeof(jvmtiEventCallbacks);
483
484 // clear in either case to be sure we got any gap between sizes
485 memset(&_event_callbacks, 0, byte_cnt);
486
487 // Now that JvmtiThreadState_lock is held, prevent a possible race condition where events
488 // are re-enabled by a call to set event callbacks where the DisposeEnvironment
489 // occurs after the boiler-plate environment check and before the lock is acquired.
490 if (callbacks != NULL && is_valid()) {
491 if (size_of_callbacks < (jint)byte_cnt) {
492 byte_cnt = size_of_callbacks;
493 }
494 memcpy(&_event_callbacks, callbacks, byte_cnt);
495 }
496 }
497
498
499 // In the fullness of time, all users of the method should instead
500 // directly use allocate, besides being cleaner and faster, this will
501 // mean much better out of memory handling
502 unsigned char *
503 JvmtiEnvBase::jvmtiMalloc(jlong size) {
504 unsigned char* mem = NULL;
505 jvmtiError result = allocate(size, &mem);
506 assert(result == JVMTI_ERROR_NONE, "Allocate failed");
507 return mem;
508 }
509
510
511 // Handle management
512
513 jobject JvmtiEnvBase::jni_reference(Handle hndl) {
514 return JNIHandles::make_local(hndl());
515 }
516
517 jobject JvmtiEnvBase::jni_reference(JavaThread *thread, Handle hndl) {
518 return JNIHandles::make_local(thread, hndl());
519 }
520
521 void JvmtiEnvBase::destroy_jni_reference(jobject jobj) {
522 JNIHandles::destroy_local(jobj);
523 }
524
525 void JvmtiEnvBase::destroy_jni_reference(JavaThread *thread, jobject jobj) {
526 JNIHandles::destroy_local(jobj); // thread is unused.
527 }
528
529 //
530 // Threads
531 //
532
533 jobject *
534 JvmtiEnvBase::new_jobjectArray(int length, Handle *handles) {
535 if (length == 0) {
536 return NULL;
537 }
538
539 jobject *objArray = (jobject *) jvmtiMalloc(sizeof(jobject) * length);
540 NULL_CHECK(objArray, NULL);
541
542 for (int i=0; i<length; i++) {
543 objArray[i] = jni_reference(handles[i]);
544 }
545 return objArray;
546 }
547
548 jthread *
549 JvmtiEnvBase::new_jthreadArray(int length, Handle *handles) {
550 return (jthread *) new_jobjectArray(length,handles);
551 }
552
553 jthreadGroup *
554 JvmtiEnvBase::new_jthreadGroupArray(int length, Handle *handles) {
555 return (jthreadGroup *) new_jobjectArray(length,handles);
556 }
557
558 // return the vframe on the specified thread and depth, NULL if no such frame
559 vframe*
560 JvmtiEnvBase::vframeFor(JavaThread* java_thread, jint depth) {
561 if (!java_thread->has_last_Java_frame()) {
562 return NULL;
563 }
564 RegisterMap reg_map(java_thread);
565 vframe *vf = java_thread->last_java_vframe(®_map);
566 int d = 0;
567 while ((vf != NULL) && (d < depth)) {
568 vf = vf->java_sender();
569 d++;
570 }
571 return vf;
572 }
573
574
575 //
576 // utilities: JNI objects
577 //
578
579
580 jclass
581 JvmtiEnvBase::get_jni_class_non_null(Klass* k) {
582 assert(k != NULL, "k != NULL");
583 Thread *thread = Thread::current();
584 return (jclass)jni_reference(Handle(thread, k->java_mirror()));
585 }
586
587 //
588 // Field Information
589 //
590
591 bool
592 JvmtiEnvBase::get_field_descriptor(Klass* k, jfieldID field, fieldDescriptor* fd) {
593 if (!jfieldIDWorkaround::is_valid_jfieldID(k, field)) {
594 return false;
595 }
596 bool found = false;
597 if (jfieldIDWorkaround::is_static_jfieldID(field)) {
598 JNIid* id = jfieldIDWorkaround::from_static_jfieldID(field);
599 found = id->find_local_field(fd);
600 } else {
601 // Non-static field. The fieldID is really the offset of the field within the object.
602 int offset = jfieldIDWorkaround::from_instance_jfieldID(k, field);
603 found = InstanceKlass::cast(k)->find_field_from_offset(offset, false, fd);
604 }
605 return found;
606 }
607
608 //
609 // Object Monitor Information
610 //
611
612 //
613 // Count the number of objects for a lightweight monitor. The hobj
614 // parameter is object that owns the monitor so this routine will
615 // count the number of times the same object was locked by frames
616 // in java_thread.
617 //
618 jint
619 JvmtiEnvBase::count_locked_objects(JavaThread *java_thread, Handle hobj) {
620 jint ret = 0;
621 if (!java_thread->has_last_Java_frame()) {
622 return ret; // no Java frames so no monitors
623 }
624
625 Thread* current_thread = Thread::current();
626 ResourceMark rm(current_thread);
627 HandleMark hm(current_thread);
628 RegisterMap reg_map(java_thread);
629
630 for(javaVFrame *jvf=java_thread->last_java_vframe(®_map); jvf != NULL;
631 jvf = jvf->java_sender()) {
632 GrowableArray<MonitorInfo*>* mons = jvf->monitors();
633 if (!mons->is_empty()) {
634 for (int i = 0; i < mons->length(); i++) {
635 MonitorInfo *mi = mons->at(i);
636 if (mi->owner_is_scalar_replaced()) continue;
637
638 // see if owner of the monitor is our object
639 if (mi->owner() != NULL && mi->owner() == hobj()) {
640 ret++;
641 }
642 }
643 }
644 }
645 return ret;
646 }
647
648
649
650 jvmtiError
651 JvmtiEnvBase::get_current_contended_monitor(JavaThread *calling_thread, JavaThread *java_thread, jobject *monitor_ptr) {
652 JavaThread *current_jt = JavaThread::current();
653 assert(current_jt == java_thread ||
654 current_jt == java_thread->active_handshaker(),
655 "call by myself or at direct handshake");
656 oop obj = NULL;
657 // The ObjectMonitor* can't be async deflated since we are either
658 // at a safepoint or the calling thread is operating on itself so
659 // it cannot leave the underlying wait()/enter() call.
660 ObjectMonitor *mon = java_thread->current_waiting_monitor();
661 if (mon == NULL) {
662 // thread is not doing an Object.wait() call
663 mon = java_thread->current_pending_monitor();
664 if (mon != NULL) {
665 // The thread is trying to enter() an ObjectMonitor.
666 obj = (oop)mon->object();
667 assert(obj != NULL, "ObjectMonitor should have a valid object!");
668 }
669 // implied else: no contended ObjectMonitor
670 } else {
671 // thread is doing an Object.wait() call
672 obj = (oop)mon->object();
673 assert(obj != NULL, "Object.wait() should have an object");
674 }
675
676 if (obj == NULL) {
677 *monitor_ptr = NULL;
678 } else {
679 HandleMark hm(current_jt);
680 Handle hobj(current_jt, obj);
681 *monitor_ptr = jni_reference(calling_thread, hobj);
682 }
683 return JVMTI_ERROR_NONE;
684 }
685
686
687 jvmtiError
688 JvmtiEnvBase::get_owned_monitors(JavaThread *calling_thread, JavaThread* java_thread,
689 GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list) {
690 jvmtiError err = JVMTI_ERROR_NONE;
691 JavaThread *current_jt = JavaThread::current();
692 assert(current_jt == java_thread ||
693 current_jt == java_thread->active_handshaker(),
694 "call by myself or at direct handshake");
695
696 if (java_thread->has_last_Java_frame()) {
697 ResourceMark rm(current_jt);
698 HandleMark hm(current_jt);
699 RegisterMap reg_map(java_thread);
700
701 int depth = 0;
702 for (javaVFrame *jvf = java_thread->last_java_vframe(®_map); jvf != NULL;
703 jvf = jvf->java_sender()) {
704 if (MaxJavaStackTraceDepth == 0 || depth++ < MaxJavaStackTraceDepth) { // check for stack too deep
705 // add locked objects for this frame into list
706 err = get_locked_objects_in_frame(calling_thread, java_thread, jvf, owned_monitors_list, depth-1);
707 if (err != JVMTI_ERROR_NONE) {
708 return err;
709 }
710 }
711 }
712 }
713
714 // Get off stack monitors. (e.g. acquired via jni MonitorEnter).
715 JvmtiMonitorClosure jmc(java_thread, calling_thread, owned_monitors_list, this);
716 ObjectSynchronizer::monitors_iterate(&jmc);
717 err = jmc.error();
718
719 return err;
720 }
721
722 // Save JNI local handles for any objects that this frame owns.
723 jvmtiError
724 JvmtiEnvBase::get_locked_objects_in_frame(JavaThread* calling_thread, JavaThread* java_thread,
725 javaVFrame *jvf, GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitors_list, jint stack_depth) {
726 jvmtiError err = JVMTI_ERROR_NONE;
727 Thread* current_thread = Thread::current();
728 ResourceMark rm(current_thread);
729 HandleMark hm(current_thread);
730
731 GrowableArray<MonitorInfo*>* mons = jvf->monitors();
732 if (mons->is_empty()) {
733 return err; // this javaVFrame holds no monitors
734 }
735
736 oop wait_obj = NULL;
737 {
738 // The ObjectMonitor* can't be async deflated since we are either
739 // at a safepoint or the calling thread is operating on itself so
740 // it cannot leave the underlying wait() call.
741 // Save object of current wait() call (if any) for later comparison.
742 ObjectMonitor *mon = java_thread->current_waiting_monitor();
743 if (mon != NULL) {
744 wait_obj = (oop)mon->object();
745 }
746 }
747 oop pending_obj = NULL;
748 {
749 // The ObjectMonitor* can't be async deflated since we are either
750 // at a safepoint or the calling thread is operating on itself so
751 // it cannot leave the underlying enter() call.
752 // Save object of current enter() call (if any) for later comparison.
753 ObjectMonitor *mon = java_thread->current_pending_monitor();
754 if (mon != NULL) {
755 pending_obj = (oop)mon->object();
756 }
757 }
758
759 for (int i = 0; i < mons->length(); i++) {
760 MonitorInfo *mi = mons->at(i);
761
762 if (mi->owner_is_scalar_replaced()) continue;
763
764 oop obj = mi->owner();
765 if (obj == NULL) {
766 // this monitor doesn't have an owning object so skip it
767 continue;
768 }
769
770 if (wait_obj == obj) {
771 // the thread is waiting on this monitor so it isn't really owned
772 continue;
773 }
774
775 if (pending_obj == obj) {
776 // the thread is pending on this monitor so it isn't really owned
777 continue;
778 }
779
780 if (owned_monitors_list->length() > 0) {
781 // Our list has at least one object on it so we have to check
782 // for recursive object locking
783 bool found = false;
784 for (int j = 0; j < owned_monitors_list->length(); j++) {
785 jobject jobj = ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(j))->monitor;
786 oop check = JNIHandles::resolve(jobj);
787 if (check == obj) {
788 found = true; // we found the object
789 break;
790 }
791 }
792
793 if (found) {
794 // already have this object so don't include it
795 continue;
796 }
797 }
798
799 // add the owning object to our list
800 jvmtiMonitorStackDepthInfo *jmsdi;
801 err = allocate(sizeof(jvmtiMonitorStackDepthInfo), (unsigned char **)&jmsdi);
802 if (err != JVMTI_ERROR_NONE) {
803 return err;
804 }
805 Handle hobj(Thread::current(), obj);
806 jmsdi->monitor = jni_reference(calling_thread, hobj);
807 jmsdi->stack_depth = stack_depth;
808 owned_monitors_list->append(jmsdi);
809 }
810
811 return err;
812 }
813
814 jvmtiError
815 JvmtiEnvBase::get_stack_trace(JavaThread *java_thread,
816 jint start_depth, jint max_count,
817 jvmtiFrameInfo* frame_buffer, jint* count_ptr) {
818 #ifdef ASSERT
819 uint32_t debug_bits = 0;
820 #endif
821 Thread *current_thread = Thread::current();
822 assert(current_thread == java_thread ||
823 SafepointSynchronize::is_at_safepoint() ||
824 current_thread == java_thread->active_handshaker(),
825 "call by myself / at safepoint / at handshake");
826 int count = 0;
827 if (java_thread->has_last_Java_frame()) {
828 RegisterMap reg_map(java_thread);
829 ResourceMark rm(current_thread);
830 javaVFrame *jvf = java_thread->last_java_vframe(®_map);
831 HandleMark hm(current_thread);
832 if (start_depth != 0) {
833 if (start_depth > 0) {
834 for (int j = 0; j < start_depth && jvf != NULL; j++) {
835 jvf = jvf->java_sender();
836 }
837 if (jvf == NULL) {
838 // start_depth is deeper than the stack depth
839 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
840 }
841 } else { // start_depth < 0
842 // we are referencing the starting depth based on the oldest
843 // part of the stack.
844 // optimize to limit the number of times that java_sender() is called
845 javaVFrame *jvf_cursor = jvf;
846 javaVFrame *jvf_prev = NULL;
847 javaVFrame *jvf_prev_prev = NULL;
848 int j = 0;
849 while (jvf_cursor != NULL) {
850 jvf_prev_prev = jvf_prev;
851 jvf_prev = jvf_cursor;
852 for (j = 0; j > start_depth && jvf_cursor != NULL; j--) {
853 jvf_cursor = jvf_cursor->java_sender();
854 }
855 }
856 if (j == start_depth) {
857 // previous pointer is exactly where we want to start
858 jvf = jvf_prev;
859 } else {
860 // we need to back up further to get to the right place
861 if (jvf_prev_prev == NULL) {
862 // the -start_depth is greater than the stack depth
863 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
864 }
865 // j now is the number of frames on the stack starting with
866 // jvf_prev, we start from jvf_prev_prev and move older on
867 // the stack that many, the result is -start_depth frames
868 // remaining.
869 jvf = jvf_prev_prev;
870 for (; j < 0; j++) {
871 jvf = jvf->java_sender();
872 }
873 }
874 }
875 }
876 for (; count < max_count && jvf != NULL; count++) {
877 frame_buffer[count].method = jvf->method()->jmethod_id();
878 frame_buffer[count].location = (jvf->method()->is_native() ? -1 : jvf->bci());
879 jvf = jvf->java_sender();
880 }
881 } else {
882 if (start_depth != 0) {
883 // no frames and there is a starting depth
884 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
885 }
886 }
887 *count_ptr = count;
888 return JVMTI_ERROR_NONE;
889 }
890
891 jvmtiError
892 JvmtiEnvBase::get_frame_count(JvmtiThreadState *state, jint *count_ptr) {
893 assert((state != NULL),
894 "JavaThread should create JvmtiThreadState before calling this method");
895 *count_ptr = state->count_frames();
896 return JVMTI_ERROR_NONE;
897 }
898
899 jvmtiError
900 JvmtiEnvBase::get_frame_location(JavaThread *java_thread, jint depth,
901 jmethodID* method_ptr, jlocation* location_ptr) {
902 #ifdef ASSERT
903 uint32_t debug_bits = 0;
904 #endif
905 Thread* current_thread = Thread::current();
906 assert(current_thread == java_thread ||
907 current_thread == java_thread->active_handshaker(),
908 "call by myself or at direct handshake");
909 ResourceMark rm(current_thread);
910
911 vframe *vf = vframeFor(java_thread, depth);
912 if (vf == NULL) {
913 return JVMTI_ERROR_NO_MORE_FRAMES;
914 }
915
916 // vframeFor should return a java frame. If it doesn't
917 // it means we've got an internal error and we return the
918 // error in product mode. In debug mode we will instead
919 // attempt to cast the vframe to a javaVFrame and will
920 // cause an assertion/crash to allow further diagnosis.
921 #ifdef PRODUCT
922 if (!vf->is_java_frame()) {
923 return JVMTI_ERROR_INTERNAL;
924 }
925 #endif
926
927 HandleMark hm(current_thread);
928 javaVFrame *jvf = javaVFrame::cast(vf);
929 Method* method = jvf->method();
930 if (method->is_native()) {
931 *location_ptr = -1;
932 } else {
933 *location_ptr = jvf->bci();
934 }
935 *method_ptr = method->jmethod_id();
936
937 return JVMTI_ERROR_NONE;
938 }
939
940
941 jvmtiError
942 JvmtiEnvBase::get_object_monitor_usage(JavaThread* calling_thread, jobject object, jvmtiMonitorUsage* info_ptr) {
943 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
944 Thread* current_thread = VMThread::vm_thread();
945 assert(current_thread == Thread::current(), "must be");
946
947 HandleMark hm(current_thread);
948 Handle hobj;
949
950 // Check arguments
951 {
952 oop mirror = JNIHandles::resolve_external_guard(object);
953 NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
954 NULL_CHECK(info_ptr, JVMTI_ERROR_NULL_POINTER);
955
956 hobj = Handle(current_thread, mirror);
957 }
958
959 ThreadsListHandle tlh(current_thread);
960 JavaThread *owning_thread = NULL;
961 ObjectMonitor *mon = NULL;
962 jvmtiMonitorUsage ret = {
963 NULL, 0, 0, NULL, 0, NULL
964 };
965
966 uint32_t debug_bits = 0;
967 // first derive the object's owner and entry_count (if any)
968 {
969 // Revoke any biases before querying the mark word
970 BiasedLocking::revoke_at_safepoint(hobj);
971
972 address owner = NULL;
973 {
974 markWord mark = hobj()->mark();
975
976 if (!mark.has_monitor()) {
977 // this object has a lightweight monitor
978
979 if (mark.has_locker()) {
980 owner = (address)mark.locker(); // save the address of the Lock word
981 }
982 // implied else: no owner
983 } else {
984 // this object has a heavyweight monitor
985 mon = mark.monitor();
986
987 // The owner field of a heavyweight monitor may be NULL for no
988 // owner, a JavaThread * or it may still be the address of the
989 // Lock word in a JavaThread's stack. A monitor can be inflated
990 // by a non-owning JavaThread, but only the owning JavaThread
991 // can change the owner field from the Lock word to the
992 // JavaThread * and it may not have done that yet.
993 owner = (address)mon->owner();
994 }
995 }
996
997 if (owner != NULL) {
998 // This monitor is owned so we have to find the owning JavaThread.
999 owning_thread = Threads::owning_thread_from_monitor_owner(tlh.list(), owner);
1000 assert(owning_thread != NULL, "owning JavaThread must not be NULL");
1001 Handle th(current_thread, owning_thread->threadObj());
1002 ret.owner = (jthread)jni_reference(calling_thread, th);
1003 }
1004
1005 if (owning_thread != NULL) { // monitor is owned
1006 // The recursions field of a monitor does not reflect recursions
1007 // as lightweight locks before inflating the monitor are not included.
1008 // We have to count the number of recursive monitor entries the hard way.
1009 // We pass a handle to survive any GCs along the way.
1010 ret.entry_count = count_locked_objects(owning_thread, hobj);
1011 }
1012 // implied else: entry_count == 0
1013 }
1014
1015 jint nWant = 0, nWait = 0;
1016 if (mon != NULL) {
1017 // this object has a heavyweight monitor
1018 nWant = mon->contentions(); // # of threads contending for monitor
1019 nWait = mon->waiters(); // # of threads in Object.wait()
1020 ret.waiter_count = nWant + nWait;
1021 ret.notify_waiter_count = nWait;
1022 } else {
1023 // this object has a lightweight monitor
1024 ret.waiter_count = 0;
1025 ret.notify_waiter_count = 0;
1026 }
1027
1028 // Allocate memory for heavyweight and lightweight monitor.
1029 jvmtiError err;
1030 err = allocate(ret.waiter_count * sizeof(jthread *), (unsigned char**)&ret.waiters);
1031 if (err != JVMTI_ERROR_NONE) {
1032 return err;
1033 }
1034 err = allocate(ret.notify_waiter_count * sizeof(jthread *),
1035 (unsigned char**)&ret.notify_waiters);
1036 if (err != JVMTI_ERROR_NONE) {
1037 deallocate((unsigned char*)ret.waiters);
1038 return err;
1039 }
1040
1041 // now derive the rest of the fields
1042 if (mon != NULL) {
1043 // this object has a heavyweight monitor
1044
1045 // Number of waiters may actually be less than the waiter count.
1046 // So NULL out memory so that unused memory will be NULL.
1047 memset(ret.waiters, 0, ret.waiter_count * sizeof(jthread *));
1048 memset(ret.notify_waiters, 0, ret.notify_waiter_count * sizeof(jthread *));
1049
1050 if (ret.waiter_count > 0) {
1051 // we have contending and/or waiting threads
1052 if (nWant > 0) {
1053 // we have contending threads
1054 ResourceMark rm(current_thread);
1055 // get_pending_threads returns only java thread so we do not need to
1056 // check for non java threads.
1057 GrowableArray<JavaThread*>* wantList = Threads::get_pending_threads(tlh.list(), nWant, (address)mon);
1058 if (wantList->length() < nWant) {
1059 // robustness: the pending list has gotten smaller
1060 nWant = wantList->length();
1061 }
1062 for (int i = 0; i < nWant; i++) {
1063 JavaThread *pending_thread = wantList->at(i);
1064 Handle th(current_thread, pending_thread->threadObj());
1065 ret.waiters[i] = (jthread)jni_reference(calling_thread, th);
1066 }
1067 }
1068 if (nWait > 0) {
1069 // we have threads in Object.wait()
1070 int offset = nWant; // add after any contending threads
1071 ObjectWaiter *waiter = mon->first_waiter();
1072 for (int i = 0, j = 0; i < nWait; i++) {
1073 if (waiter == NULL) {
1074 // robustness: the waiting list has gotten smaller
1075 nWait = j;
1076 break;
1077 }
1078 Thread *t = mon->thread_of_waiter(waiter);
1079 if (t != NULL && t->is_Java_thread()) {
1080 JavaThread *wjava_thread = (JavaThread *)t;
1081 // If the thread was found on the ObjectWaiter list, then
1082 // it has not been notified. This thread can't change the
1083 // state of the monitor so it doesn't need to be suspended.
1084 Handle th(current_thread, wjava_thread->threadObj());
1085 ret.waiters[offset + j] = (jthread)jni_reference(calling_thread, th);
1086 ret.notify_waiters[j++] = (jthread)jni_reference(calling_thread, th);
1087 }
1088 waiter = mon->next_waiter(waiter);
1089 }
1090 }
1091 } // ThreadsListHandle is destroyed here.
1092
1093 // Adjust count. nWant and nWait count values may be less than original.
1094 ret.waiter_count = nWant + nWait;
1095 ret.notify_waiter_count = nWait;
1096 } else {
1097 // this object has a lightweight monitor and we have nothing more
1098 // to do here because the defaults are just fine.
1099 }
1100
1101 // we don't update return parameter unless everything worked
1102 *info_ptr = ret;
1103
1104 return JVMTI_ERROR_NONE;
1105 }
1106
1107 ResourceTracker::ResourceTracker(JvmtiEnv* env) {
1108 _env = env;
1109 _allocations = new (ResourceObj::C_HEAP, mtServiceability) GrowableArray<unsigned char*>(20, mtServiceability);
1110 _failed = false;
1111 }
1112 ResourceTracker::~ResourceTracker() {
1113 if (_failed) {
1114 for (int i=0; i<_allocations->length(); i++) {
1115 _env->deallocate(_allocations->at(i));
1116 }
1117 }
1118 delete _allocations;
1119 }
1120
1121 jvmtiError ResourceTracker::allocate(jlong size, unsigned char** mem_ptr) {
1122 unsigned char *ptr;
1123 jvmtiError err = _env->allocate(size, &ptr);
1124 if (err == JVMTI_ERROR_NONE) {
1125 _allocations->append(ptr);
1126 *mem_ptr = ptr;
1127 } else {
1128 *mem_ptr = NULL;
1129 _failed = true;
1130 }
1131 return err;
1132 }
1133
1134 unsigned char* ResourceTracker::allocate(jlong size) {
1135 unsigned char* ptr;
1136 allocate(size, &ptr);
1137 return ptr;
1138 }
1139
1140 char* ResourceTracker::strdup(const char* str) {
1141 char *dup_str = (char*)allocate(strlen(str)+1);
1142 if (dup_str != NULL) {
1143 strcpy(dup_str, str);
1144 }
1145 return dup_str;
1146 }
1147
1148 struct StackInfoNode {
1149 struct StackInfoNode *next;
1150 jvmtiStackInfo info;
1151 };
1152
1153 // Create a jvmtiStackInfo inside a linked list node and create a
1154 // buffer for the frame information, both allocated as resource objects.
1155 // Fill in both the jvmtiStackInfo and the jvmtiFrameInfo.
1156 // Note that either or both of thr and thread_oop
1157 // may be null if the thread is new or has exited.
1158 void
1159 MultipleStackTracesCollector::fill_frames(jthread jt, JavaThread *thr, oop thread_oop) {
1160 #ifdef ASSERT
1161 Thread *current_thread = Thread::current();
1162 assert(current_thread == thr ||
1163 SafepointSynchronize::is_at_safepoint() ||
1164 current_thread == thr->active_handshaker(),
1165 "call by myself / at safepoint / at handshake");
1166 #endif
1167
1168 jint state = 0;
1169 struct StackInfoNode *node = NEW_RESOURCE_OBJ(struct StackInfoNode);
1170 jvmtiStackInfo *infop = &(node->info);
1171 node->next = head();
1172 set_head(node);
1173 infop->frame_count = 0;
1174 infop->thread = jt;
1175
1176 if (thread_oop != NULL) {
1177 // get most state bits
1178 state = (jint)java_lang_Thread::get_thread_status(thread_oop);
1179 }
1180
1181 if (thr != NULL) { // add more state bits if there is a JavaThead to query
1182 // same as is_being_ext_suspended() but without locking
1183 if (thr->is_ext_suspended() || thr->is_external_suspend()) {
1184 state |= JVMTI_THREAD_STATE_SUSPENDED;
1185 }
1186 JavaThreadState jts = thr->thread_state();
1187 if (jts == _thread_in_native) {
1188 state |= JVMTI_THREAD_STATE_IN_NATIVE;
1189 }
1190 if (thr->is_interrupted(false)) {
1191 state |= JVMTI_THREAD_STATE_INTERRUPTED;
1192 }
1193 }
1194 infop->state = state;
1195
1196 if (thr != NULL && (state & JVMTI_THREAD_STATE_ALIVE) != 0) {
1197 infop->frame_buffer = NEW_RESOURCE_ARRAY(jvmtiFrameInfo, max_frame_count());
1198 env()->get_stack_trace(thr, 0, max_frame_count(),
1199 infop->frame_buffer, &(infop->frame_count));
1200 } else {
1201 infop->frame_buffer = NULL;
1202 infop->frame_count = 0;
1203 }
1204 _frame_count_total += infop->frame_count;
1205 }
1206
1207 // Based on the stack information in the linked list, allocate memory
1208 // block to return and fill it from the info in the linked list.
1209 void
1210 MultipleStackTracesCollector::allocate_and_fill_stacks(jint thread_count) {
1211 // do I need to worry about alignment issues?
1212 jlong alloc_size = thread_count * sizeof(jvmtiStackInfo)
1213 + _frame_count_total * sizeof(jvmtiFrameInfo);
1214 env()->allocate(alloc_size, (unsigned char **)&_stack_info);
1215
1216 // pointers to move through the newly allocated space as it is filled in
1217 jvmtiStackInfo *si = _stack_info + thread_count; // bottom of stack info
1218 jvmtiFrameInfo *fi = (jvmtiFrameInfo *)si; // is the top of frame info
1219
1220 // copy information in resource area into allocated buffer
1221 // insert stack info backwards since linked list is backwards
1222 // insert frame info forwards
1223 // walk the StackInfoNodes
1224 for (struct StackInfoNode *sin = head(); sin != NULL; sin = sin->next) {
1225 jint frame_count = sin->info.frame_count;
1226 size_t frames_size = frame_count * sizeof(jvmtiFrameInfo);
1227 --si;
1228 memcpy(si, &(sin->info), sizeof(jvmtiStackInfo));
1229 if (frames_size == 0) {
1230 si->frame_buffer = NULL;
1231 } else {
1232 memcpy(fi, sin->info.frame_buffer, frames_size);
1233 si->frame_buffer = fi; // point to the new allocated copy of the frames
1234 fi += frame_count;
1235 }
1236 }
1237 assert(si == _stack_info, "the last copied stack info must be the first record");
1238 assert((unsigned char *)fi == ((unsigned char *)_stack_info) + alloc_size,
1239 "the last copied frame info must be the last record");
1240 }
1241
1242
1243 void
1244 VM_GetThreadListStackTraces::doit() {
1245 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1246
1247 ResourceMark rm;
1248 ThreadsListHandle tlh;
1249 for (int i = 0; i < _thread_count; ++i) {
1250 jthread jt = _thread_list[i];
1251 JavaThread* java_thread = NULL;
1252 oop thread_oop = NULL;
1253 jvmtiError err = JvmtiExport::cv_external_thread_to_JavaThread(tlh.list(), jt, &java_thread, &thread_oop);
1254 if (err != JVMTI_ERROR_NONE) {
1255 // We got an error code so we don't have a JavaThread *, but
1256 // only return an error from here if we didn't get a valid
1257 // thread_oop.
1258 if (thread_oop == NULL) {
1259 _collector.set_result(err);
1260 return;
1261 }
1262 // We have a valid thread_oop.
1263 }
1264 _collector.fill_frames(jt, java_thread, thread_oop);
1265 }
1266 _collector.allocate_and_fill_stacks(_thread_count);
1267 }
1268
1269 void
1270 GetSingleStackTraceClosure::do_thread(Thread *target) {
1271 assert(target->is_Java_thread(), "just checking");
1272 JavaThread *jt = (JavaThread *)target;
1273 oop thread_oop = jt->threadObj();
1274
1275 if (!jt->is_exiting() && thread_oop != NULL) {
1276 ResourceMark rm;
1277 _collector.fill_frames(_jthread, jt, thread_oop);
1278 _collector.allocate_and_fill_stacks(1);
1279 }
1280 }
1281
1282 void
1283 VM_GetAllStackTraces::doit() {
1284 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1285
1286 ResourceMark rm;
1287 _final_thread_count = 0;
1288 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *jt = jtiwh.next(); ) {
1289 oop thread_oop = jt->threadObj();
1290 if (thread_oop != NULL &&
1291 !jt->is_exiting() &&
1292 java_lang_Thread::is_alive(thread_oop) &&
1293 !jt->is_hidden_from_external_view()) {
1294 ++_final_thread_count;
1295 // Handle block of the calling thread is used to create local refs.
1296 _collector.fill_frames((jthread)JNIHandles::make_local(_calling_thread, thread_oop),
1297 jt, thread_oop);
1298 }
1299 }
1300 _collector.allocate_and_fill_stacks(_final_thread_count);
1301 }
1302
1303 // Verifies that the top frame is a java frame in an expected state.
1304 // Deoptimizes frame if needed.
1305 // Checks that the frame method signature matches the return type (tos).
1306 // HandleMark must be defined in the caller only.
1307 // It is to keep a ret_ob_h handle alive after return to the caller.
1308 jvmtiError
1309 JvmtiEnvBase::check_top_frame(JavaThread* current_thread, JavaThread* java_thread,
1310 jvalue value, TosState tos, Handle* ret_ob_h) {
1311 ResourceMark rm(current_thread);
1312
1313 vframe *vf = vframeFor(java_thread, 0);
1314 NULL_CHECK(vf, JVMTI_ERROR_NO_MORE_FRAMES);
1315
1316 javaVFrame *jvf = (javaVFrame*) vf;
1317 if (!vf->is_java_frame() || jvf->method()->is_native()) {
1318 return JVMTI_ERROR_OPAQUE_FRAME;
1319 }
1320
1321 // If the frame is a compiled one, need to deoptimize it.
1322 if (vf->is_compiled_frame()) {
1323 if (!vf->fr().can_be_deoptimized()) {
1324 return JVMTI_ERROR_OPAQUE_FRAME;
1325 }
1326 Deoptimization::deoptimize_frame(java_thread, jvf->fr().id());
1327 }
1328
1329 // Get information about method return type
1330 Symbol* signature = jvf->method()->signature();
1331
1332 ResultTypeFinder rtf(signature);
1333 TosState fr_tos = as_TosState(rtf.type());
1334 if (fr_tos != tos) {
1335 if (tos != itos || (fr_tos != btos && fr_tos != ztos && fr_tos != ctos && fr_tos != stos)) {
1336 return JVMTI_ERROR_TYPE_MISMATCH;
1337 }
1338 }
1339
1340 // Check that the jobject class matches the return type signature.
1341 jobject jobj = value.l;
1342 if (tos == atos && jobj != NULL) { // NULL reference is allowed
1343 Handle ob_h(current_thread, JNIHandles::resolve_external_guard(jobj));
1344 NULL_CHECK(ob_h, JVMTI_ERROR_INVALID_OBJECT);
1345 Klass* ob_k = ob_h()->klass();
1346 NULL_CHECK(ob_k, JVMTI_ERROR_INVALID_OBJECT);
1347
1348 // Method return type signature.
1349 char* ty_sign = 1 + strchr(signature->as_C_string(), JVM_SIGNATURE_ENDFUNC);
1350
1351 if (!VM_GetOrSetLocal::is_assignable(ty_sign, ob_k, current_thread)) {
1352 return JVMTI_ERROR_TYPE_MISMATCH;
1353 }
1354 *ret_ob_h = ob_h;
1355 }
1356 return JVMTI_ERROR_NONE;
1357 } /* end check_top_frame */
1358
1359
1360 // ForceEarlyReturn<type> follows the PopFrame approach in many aspects.
1361 // Main difference is on the last stage in the interpreter.
1362 // The PopFrame stops method execution to continue execution
1363 // from the same method call instruction.
1364 // The ForceEarlyReturn forces return from method so the execution
1365 // continues at the bytecode following the method call.
1366
1367 // Threads_lock NOT held, java_thread not protected by lock
1368 // java_thread - pre-checked
1369
1370 jvmtiError
1371 JvmtiEnvBase::force_early_return(JavaThread* java_thread, jvalue value, TosState tos) {
1372 JavaThread* current_thread = JavaThread::current();
1373 HandleMark hm(current_thread);
1374 uint32_t debug_bits = 0;
1375
1376 // retrieve or create the state
1377 JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread);
1378 if (state == NULL) {
1379 return JVMTI_ERROR_THREAD_NOT_ALIVE;
1380 }
1381
1382 // Check if java_thread is fully suspended
1383 if (!java_thread->is_thread_fully_suspended(true /* wait for suspend completion */, &debug_bits)) {
1384 return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
1385 }
1386
1387 // Check to see if a ForceEarlyReturn was already in progress
1388 if (state->is_earlyret_pending()) {
1389 // Probably possible for JVMTI clients to trigger this, but the
1390 // JPDA backend shouldn't allow this to happen
1391 return JVMTI_ERROR_INTERNAL;
1392 }
1393 {
1394 // The same as for PopFrame. Workaround bug:
1395 // 4812902: popFrame hangs if the method is waiting at a synchronize
1396 // Catch this condition and return an error to avoid hanging.
1397 // Now JVMTI spec allows an implementation to bail out with an opaque
1398 // frame error.
1399 OSThread* osThread = java_thread->osthread();
1400 if (osThread->get_state() == MONITOR_WAIT) {
1401 return JVMTI_ERROR_OPAQUE_FRAME;
1402 }
1403 }
1404 Handle ret_ob_h;
1405 jvmtiError err = check_top_frame(current_thread, java_thread, value, tos, &ret_ob_h);
1406 if (err != JVMTI_ERROR_NONE) {
1407 return err;
1408 }
1409 assert(tos != atos || value.l == NULL || ret_ob_h() != NULL,
1410 "return object oop must not be NULL if jobject is not NULL");
1411
1412 // Update the thread state to reflect that the top frame must be
1413 // forced to return.
1414 // The current frame will be returned later when the suspended
1415 // thread is resumed and right before returning from VM to Java.
1416 // (see call_VM_base() in assembler_<cpu>.cpp).
1417
1418 state->set_earlyret_pending();
1419 state->set_earlyret_oop(ret_ob_h());
1420 state->set_earlyret_value(value, tos);
1421
1422 // Set pending step flag for this early return.
1423 // It is cleared when next step event is posted.
1424 state->set_pending_step_for_earlyret();
1425
1426 return JVMTI_ERROR_NONE;
1427 } /* end force_early_return */
1428
1429 void
1430 JvmtiMonitorClosure::do_monitor(ObjectMonitor* mon) {
1431 if ( _error != JVMTI_ERROR_NONE) {
1432 // Error occurred in previous iteration so no need to add
1433 // to the list.
1434 return;
1435 }
1436 if (mon->owner() == _java_thread ) {
1437 // Filter out on stack monitors collected during stack walk.
1438 oop obj = (oop)mon->object();
1439 bool found = false;
1440 for (int j = 0; j < _owned_monitors_list->length(); j++) {
1441 jobject jobj = ((jvmtiMonitorStackDepthInfo*)_owned_monitors_list->at(j))->monitor;
1442 oop check = JNIHandles::resolve(jobj);
1443 if (check == obj) {
1444 // On stack monitor already collected during the stack walk.
1445 found = true;
1446 break;
1447 }
1448 }
1449 if (found == false) {
1450 // This is off stack monitor (e.g. acquired via jni MonitorEnter).
1451 jvmtiError err;
1452 jvmtiMonitorStackDepthInfo *jmsdi;
1453 err = _env->allocate(sizeof(jvmtiMonitorStackDepthInfo), (unsigned char **)&jmsdi);
1454 if (err != JVMTI_ERROR_NONE) {
1455 _error = err;
1456 return;
1457 }
1458 Handle hobj(Thread::current(), obj);
1459 jmsdi->monitor = _env->jni_reference(_calling_thread, hobj);
1460 // stack depth is unknown for this monitor.
1461 jmsdi->stack_depth = -1;
1462 _owned_monitors_list->append(jmsdi);
1463 }
1464 }
1465 }
1466
1467 GrowableArray<OopHandle>* JvmtiModuleClosure::_tbl = NULL;
1468
1469 void JvmtiModuleClosure::do_module(ModuleEntry* entry) {
1470 assert_locked_or_safepoint(Module_lock);
1471 OopHandle module = entry->module_handle();
1472 guarantee(module.resolve() != NULL, "module object is NULL");
1473 _tbl->push(module);
1474 }
1475
1476 jvmtiError
1477 JvmtiModuleClosure::get_all_modules(JvmtiEnv* env, jint* module_count_ptr, jobject** modules_ptr) {
1478 ResourceMark rm;
1479 MutexLocker mcld(ClassLoaderDataGraph_lock);
1480 MutexLocker ml(Module_lock);
1481
1482 _tbl = new GrowableArray<OopHandle>(77);
1483 if (_tbl == NULL) {
1484 return JVMTI_ERROR_OUT_OF_MEMORY;
1485 }
1486
1487 // Iterate over all the modules loaded to the system.
1488 ClassLoaderDataGraph::modules_do(&do_module);
1489
1490 jint len = _tbl->length();
1491 guarantee(len > 0, "at least one module must be present");
1492
1493 jobject* array = (jobject*)env->jvmtiMalloc((jlong)(len * sizeof(jobject)));
1494 if (array == NULL) {
1495 return JVMTI_ERROR_OUT_OF_MEMORY;
1496 }
1497 for (jint idx = 0; idx < len; idx++) {
1498 array[idx] = JNIHandles::make_local(Thread::current(), _tbl->at(idx).resolve());
1499 }
1500 _tbl = NULL;
1501 *modules_ptr = array;
1502 *module_count_ptr = len;
1503 return JVMTI_ERROR_NONE;
1504 }
1505
1506 void
1507 UpdateForPopTopFrameClosure::do_thread(Thread *target) {
1508 JavaThread* jt = _state->get_thread();
1509 assert(jt == target, "just checking");
1510 if (!jt->is_exiting() && jt->threadObj() != NULL) {
1511 _state->update_for_pop_top_frame();
1512 _result = JVMTI_ERROR_NONE;
1513 }
1514 }
1515
1516 void
1517 SetFramePopClosure::do_thread(Thread *target) {
1518 JavaThread* jt = _state->get_thread();
1519 assert(jt == target, "just checking");
1520 if (!jt->is_exiting() && jt->threadObj() != NULL) {
1521 int frame_number = _state->count_frames() - _depth;
1522 _state->env_thread_state((JvmtiEnvBase*)_env)->set_frame_pop(frame_number);
1523 _result = JVMTI_ERROR_NONE;
1524 }
1525 }
1526
1527 void
1528 GetOwnedMonitorInfoClosure::do_thread(Thread *target) {
1529 assert(target->is_Java_thread(), "just checking");
1530 JavaThread *jt = (JavaThread *)target;
1531 if (!jt->is_exiting() && (jt->threadObj() != NULL)) {
1532 _result = ((JvmtiEnvBase *)_env)->get_owned_monitors(_calling_thread,
1533 jt,
1534 _owned_monitors_list);
1535 }
1536 }
1537
1538 void
1539 GetCurrentContendedMonitorClosure::do_thread(Thread *target) {
1540 assert(target->is_Java_thread(), "just checking");
1541 JavaThread *jt = (JavaThread *)target;
1542 if (!jt->is_exiting() && (jt->threadObj() != NULL)) {
1543 _result = ((JvmtiEnvBase *)_env)->get_current_contended_monitor(_calling_thread,
1544 jt,
1545 _owned_monitor_ptr);
1546 }
1547 }
1548
1549 void
1550 GetStackTraceClosure::do_thread(Thread *target) {
1551 assert(target->is_Java_thread(), "just checking");
1552 JavaThread *jt = (JavaThread *)target;
1553 if (!jt->is_exiting() && jt->threadObj() != NULL) {
1554 _result = ((JvmtiEnvBase *)_env)->get_stack_trace(jt,
1555 _start_depth, _max_count,
1556 _frame_buffer, _count_ptr);
1557 }
1558 }
1559
1560 void
1561 GetFrameCountClosure::do_thread(Thread *target) {
1562 JavaThread* jt = _state->get_thread();
1563 assert(target == jt, "just checking");
1564 if (!jt->is_exiting() && jt->threadObj() != NULL) {
1565 _result = ((JvmtiEnvBase*)_env)->get_frame_count(_state, _count_ptr);
1566 }
1567 }
1568
1569 void
1570 GetFrameLocationClosure::do_thread(Thread *target) {
1571 assert(target->is_Java_thread(), "just checking");
1572 JavaThread *jt = (JavaThread *)target;
1573 if (!jt->is_exiting() && jt->threadObj() != NULL) {
1574 _result = ((JvmtiEnvBase*)_env)->get_frame_location(jt, _depth,
1575 _method_ptr, _location_ptr);
1576 }
1577 }