Fri, 13 Sep 2013 12:48:50 -0700
8024346: ~CautiouslyPreserveExceptionMark - assert(!_thread->has_pending_exception()) failed: unexpected exception generated
Summary: Pending exceptions must be handled properly after a call to the JVMTI merge_cp_and_rewrite
Reviewed-by: coleenp, dholmes
Contributed-by: serguei.spitsyn@oracle.com
1 /*
2 * Copyright (c) 2003, 2013, 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 */
25 #include "precompiled.hpp"
26 #include "classfile/systemDictionary.hpp"
27 #include "jvmtifiles/jvmtiEnv.hpp"
28 #include "oops/objArrayKlass.hpp"
29 #include "oops/objArrayOop.hpp"
30 #include "prims/jvmtiEnvBase.hpp"
31 #include "prims/jvmtiEventController.inline.hpp"
32 #include "prims/jvmtiExtensions.hpp"
33 #include "prims/jvmtiImpl.hpp"
34 #include "prims/jvmtiManageCapabilities.hpp"
35 #include "prims/jvmtiTagMap.hpp"
36 #include "prims/jvmtiThreadState.inline.hpp"
37 #include "runtime/biasedLocking.hpp"
38 #include "runtime/deoptimization.hpp"
39 #include "runtime/interfaceSupport.hpp"
40 #include "runtime/jfieldIDWorkaround.hpp"
41 #include "runtime/objectMonitor.hpp"
42 #include "runtime/objectMonitor.inline.hpp"
43 #include "runtime/signature.hpp"
44 #include "runtime/vframe.hpp"
45 #include "runtime/vframe_hp.hpp"
46 #include "runtime/vmThread.hpp"
47 #include "runtime/vm_operations.hpp"
49 ///////////////////////////////////////////////////////////////
50 //
51 // JvmtiEnvBase
52 //
54 JvmtiEnvBase* JvmtiEnvBase::_head_environment = NULL;
56 bool JvmtiEnvBase::_globally_initialized = false;
57 volatile bool JvmtiEnvBase::_needs_clean_up = false;
59 jvmtiPhase JvmtiEnvBase::_phase = JVMTI_PHASE_PRIMORDIAL;
61 volatile int JvmtiEnvBase::_dying_thread_env_iteration_count = 0;
63 extern jvmtiInterface_1_ jvmti_Interface;
64 extern jvmtiInterface_1_ jvmtiTrace_Interface;
67 // perform initializations that must occur before any JVMTI environments
68 // are released but which should only be initialized once (no matter
69 // how many environments are created).
70 void
71 JvmtiEnvBase::globally_initialize() {
72 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
73 assert(_globally_initialized == false, "bad call");
75 JvmtiManageCapabilities::initialize();
77 // register extension functions and events
78 JvmtiExtensions::register_extensions();
80 #ifdef JVMTI_TRACE
81 JvmtiTrace::initialize();
82 #endif
84 _globally_initialized = true;
85 }
88 void
89 JvmtiEnvBase::initialize() {
90 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
92 // Add this environment to the end of the environment list (order is important)
93 {
94 // This block of code must not contain any safepoints, as list deallocation
95 // (which occurs at a safepoint) cannot occur simultaneously with this list
96 // addition. Note: No_Safepoint_Verifier cannot, currently, be used before
97 // threads exist.
98 JvmtiEnvIterator it;
99 JvmtiEnvBase *previous_env = NULL;
100 for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
101 previous_env = env;
102 }
103 if (previous_env == NULL) {
104 _head_environment = this;
105 } else {
106 previous_env->set_next_environment(this);
107 }
108 }
110 if (_globally_initialized == false) {
111 globally_initialize();
112 }
113 }
116 bool
117 JvmtiEnvBase::is_valid() {
118 jint value = 0;
120 // This object might not be a JvmtiEnvBase so we can't assume
121 // the _magic field is properly aligned. Get the value in a safe
122 // way and then check against JVMTI_MAGIC.
124 switch (sizeof(_magic)) {
125 case 2:
126 value = Bytes::get_native_u2((address)&_magic);
127 break;
129 case 4:
130 value = Bytes::get_native_u4((address)&_magic);
131 break;
133 case 8:
134 value = Bytes::get_native_u8((address)&_magic);
135 break;
137 default:
138 guarantee(false, "_magic field is an unexpected size");
139 }
141 return value == JVMTI_MAGIC;
142 }
145 bool
146 JvmtiEnvBase::use_version_1_0_semantics() {
147 int major, minor, micro;
149 JvmtiExport::decode_version_values(_version, &major, &minor, µ);
150 return major == 1 && minor == 0; // micro version doesn't matter here
151 }
154 bool
155 JvmtiEnvBase::use_version_1_1_semantics() {
156 int major, minor, micro;
158 JvmtiExport::decode_version_values(_version, &major, &minor, µ);
159 return major == 1 && minor == 1; // micro version doesn't matter here
160 }
162 bool
163 JvmtiEnvBase::use_version_1_2_semantics() {
164 int major, minor, micro;
166 JvmtiExport::decode_version_values(_version, &major, &minor, µ);
167 return major == 1 && minor == 2; // micro version doesn't matter here
168 }
171 JvmtiEnvBase::JvmtiEnvBase(jint version) : _env_event_enable() {
172 _version = version;
173 _env_local_storage = NULL;
174 _tag_map = NULL;
175 _native_method_prefix_count = 0;
176 _native_method_prefixes = NULL;
177 _next = NULL;
178 _class_file_load_hook_ever_enabled = false;
180 // Moot since ClassFileLoadHook not yet enabled.
181 // But "true" will give a more predictable ClassFileLoadHook behavior
182 // for environment creation during ClassFileLoadHook.
183 _is_retransformable = true;
185 // all callbacks initially NULL
186 memset(&_event_callbacks,0,sizeof(jvmtiEventCallbacks));
188 // all capabilities initially off
189 memset(&_current_capabilities, 0, sizeof(_current_capabilities));
191 // all prohibited capabilities initially off
192 memset(&_prohibited_capabilities, 0, sizeof(_prohibited_capabilities));
194 _magic = JVMTI_MAGIC;
196 JvmtiEventController::env_initialize((JvmtiEnv*)this);
198 #ifdef JVMTI_TRACE
199 _jvmti_external.functions = TraceJVMTI != NULL ? &jvmtiTrace_Interface : &jvmti_Interface;
200 #else
201 _jvmti_external.functions = &jvmti_Interface;
202 #endif
203 }
206 void
207 JvmtiEnvBase::dispose() {
209 #ifdef JVMTI_TRACE
210 JvmtiTrace::shutdown();
211 #endif
213 // Dispose of event info and let the event controller call us back
214 // in a locked state (env_dispose, below)
215 JvmtiEventController::env_dispose(this);
216 }
218 void
219 JvmtiEnvBase::env_dispose() {
220 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
222 // We have been entered with all events disabled on this environment.
223 // A race to re-enable events (by setting callbacks) is prevented by
224 // checking for a valid environment when setting callbacks (while
225 // holding the JvmtiThreadState_lock).
227 // Mark as invalid.
228 _magic = DISPOSED_MAGIC;
230 // Relinquish all capabilities.
231 jvmtiCapabilities *caps = get_capabilities();
232 JvmtiManageCapabilities::relinquish_capabilities(caps, caps, caps);
234 // Same situation as with events (see above)
235 set_native_method_prefixes(0, NULL);
237 JvmtiTagMap* tag_map_to_deallocate = _tag_map;
238 set_tag_map(NULL);
239 // A tag map can be big, deallocate it now
240 if (tag_map_to_deallocate != NULL) {
241 delete tag_map_to_deallocate;
242 }
244 _needs_clean_up = true;
245 }
248 JvmtiEnvBase::~JvmtiEnvBase() {
249 assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
251 // There is a small window of time during which the tag map of a
252 // disposed environment could have been reallocated.
253 // Make sure it is gone.
254 JvmtiTagMap* tag_map_to_deallocate = _tag_map;
255 set_tag_map(NULL);
256 // A tag map can be big, deallocate it now
257 if (tag_map_to_deallocate != NULL) {
258 delete tag_map_to_deallocate;
259 }
261 _magic = BAD_MAGIC;
262 }
265 void
266 JvmtiEnvBase::periodic_clean_up() {
267 assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
269 // JvmtiEnvBase reference is saved in JvmtiEnvThreadState. So
270 // clean up JvmtiThreadState before deleting JvmtiEnv pointer.
271 JvmtiThreadState::periodic_clean_up();
273 // Unlink all invalid environments from the list of environments
274 // and deallocate them
275 JvmtiEnvIterator it;
276 JvmtiEnvBase* previous_env = NULL;
277 JvmtiEnvBase* env = it.first();
278 while (env != NULL) {
279 if (env->is_valid()) {
280 previous_env = env;
281 env = it.next(env);
282 } else {
283 // This one isn't valid, remove it from the list and deallocate it
284 JvmtiEnvBase* defunct_env = env;
285 env = it.next(env);
286 if (previous_env == NULL) {
287 _head_environment = env;
288 } else {
289 previous_env->set_next_environment(env);
290 }
291 delete defunct_env;
292 }
293 }
295 }
298 void
299 JvmtiEnvBase::check_for_periodic_clean_up() {
300 assert(SafepointSynchronize::is_at_safepoint(), "sanity check");
302 class ThreadInsideIterationClosure: public ThreadClosure {
303 private:
304 bool _inside;
305 public:
306 ThreadInsideIterationClosure() : _inside(false) {};
308 void do_thread(Thread* thread) {
309 _inside |= thread->is_inside_jvmti_env_iteration();
310 }
312 bool is_inside_jvmti_env_iteration() {
313 return _inside;
314 }
315 };
317 if (_needs_clean_up) {
318 // Check if we are currently iterating environment,
319 // deallocation should not occur if we are
320 ThreadInsideIterationClosure tiic;
321 Threads::threads_do(&tiic);
322 if (!tiic.is_inside_jvmti_env_iteration() &&
323 !is_inside_dying_thread_env_iteration()) {
324 _needs_clean_up = false;
325 JvmtiEnvBase::periodic_clean_up();
326 }
327 }
328 }
331 void
332 JvmtiEnvBase::record_first_time_class_file_load_hook_enabled() {
333 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(),
334 "sanity check");
336 if (!_class_file_load_hook_ever_enabled) {
337 _class_file_load_hook_ever_enabled = true;
339 if (get_capabilities()->can_retransform_classes) {
340 _is_retransformable = true;
341 } else {
342 _is_retransformable = false;
344 // cannot add retransform capability after ClassFileLoadHook has been enabled
345 get_prohibited_capabilities()->can_retransform_classes = 1;
346 }
347 }
348 }
351 void
352 JvmtiEnvBase::record_class_file_load_hook_enabled() {
353 if (!_class_file_load_hook_ever_enabled) {
354 if (Threads::number_of_threads() == 0) {
355 record_first_time_class_file_load_hook_enabled();
356 } else {
357 MutexLocker mu(JvmtiThreadState_lock);
358 record_first_time_class_file_load_hook_enabled();
359 }
360 }
361 }
364 jvmtiError
365 JvmtiEnvBase::set_native_method_prefixes(jint prefix_count, char** prefixes) {
366 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(),
367 "sanity check");
369 int old_prefix_count = get_native_method_prefix_count();
370 char **old_prefixes = get_native_method_prefixes();
372 // allocate and install the new prefixex
373 if (prefix_count == 0 || !is_valid()) {
374 _native_method_prefix_count = 0;
375 _native_method_prefixes = NULL;
376 } else {
377 // there are prefixes, allocate an array to hold them, and fill it
378 char** new_prefixes = (char**)os::malloc((prefix_count) * sizeof(char*), mtInternal);
379 if (new_prefixes == NULL) {
380 return JVMTI_ERROR_OUT_OF_MEMORY;
381 }
382 for (int i = 0; i < prefix_count; i++) {
383 char* prefix = prefixes[i];
384 if (prefix == NULL) {
385 for (int j = 0; j < (i-1); j++) {
386 os::free(new_prefixes[j]);
387 }
388 os::free(new_prefixes);
389 return JVMTI_ERROR_NULL_POINTER;
390 }
391 prefix = os::strdup(prefixes[i]);
392 if (prefix == NULL) {
393 for (int j = 0; j < (i-1); j++) {
394 os::free(new_prefixes[j]);
395 }
396 os::free(new_prefixes);
397 return JVMTI_ERROR_OUT_OF_MEMORY;
398 }
399 new_prefixes[i] = prefix;
400 }
401 _native_method_prefix_count = prefix_count;
402 _native_method_prefixes = new_prefixes;
403 }
405 // now that we know the new prefixes have been successfully installed we can
406 // safely remove the old ones
407 if (old_prefix_count != 0) {
408 for (int i = 0; i < old_prefix_count; i++) {
409 os::free(old_prefixes[i]);
410 }
411 os::free(old_prefixes);
412 }
414 return JVMTI_ERROR_NONE;
415 }
418 // Collect all the prefixes which have been set in any JVM TI environments
419 // by the SetNativeMethodPrefix(es) functions. Be sure to maintain the
420 // order of environments and the order of prefixes within each environment.
421 // Return in a resource allocated array.
422 char**
423 JvmtiEnvBase::get_all_native_method_prefixes(int* count_ptr) {
424 assert(Threads::number_of_threads() == 0 ||
425 SafepointSynchronize::is_at_safepoint() ||
426 JvmtiThreadState_lock->is_locked(),
427 "sanity check");
429 int total_count = 0;
430 GrowableArray<char*>* prefix_array =new GrowableArray<char*>(5);
432 JvmtiEnvIterator it;
433 for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
434 int prefix_count = env->get_native_method_prefix_count();
435 char** prefixes = env->get_native_method_prefixes();
436 for (int j = 0; j < prefix_count; j++) {
437 // retrieve a prefix and so that it is safe against asynchronous changes
438 // copy it into the resource area
439 char* prefix = prefixes[j];
440 char* prefix_copy = NEW_RESOURCE_ARRAY(char, strlen(prefix)+1);
441 strcpy(prefix_copy, prefix);
442 prefix_array->at_put_grow(total_count++, prefix_copy);
443 }
444 }
446 char** all_prefixes = NEW_RESOURCE_ARRAY(char*, total_count);
447 char** p = all_prefixes;
448 for (int i = 0; i < total_count; ++i) {
449 *p++ = prefix_array->at(i);
450 }
451 *count_ptr = total_count;
452 return all_prefixes;
453 }
455 void
456 JvmtiEnvBase::set_event_callbacks(const jvmtiEventCallbacks* callbacks,
457 jint size_of_callbacks) {
458 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
460 size_t byte_cnt = sizeof(jvmtiEventCallbacks);
462 // clear in either case to be sure we got any gap between sizes
463 memset(&_event_callbacks, 0, byte_cnt);
465 // Now that JvmtiThreadState_lock is held, prevent a possible race condition where events
466 // are re-enabled by a call to set event callbacks where the DisposeEnvironment
467 // occurs after the boiler-plate environment check and before the lock is acquired.
468 if (callbacks != NULL && is_valid()) {
469 if (size_of_callbacks < (jint)byte_cnt) {
470 byte_cnt = size_of_callbacks;
471 }
472 memcpy(&_event_callbacks, callbacks, byte_cnt);
473 }
474 }
476 // Called from JVMTI entry points which perform stack walking. If the
477 // associated JavaThread is the current thread, then wait_for_suspend
478 // is not used. Otherwise, it determines if we should wait for the
479 // "other" thread to complete external suspension. (NOTE: in future
480 // releases the suspension mechanism should be reimplemented so this
481 // is not necessary.)
482 //
483 bool
484 JvmtiEnvBase::is_thread_fully_suspended(JavaThread* thr, bool wait_for_suspend, uint32_t *bits) {
485 // "other" threads require special handling
486 if (thr != JavaThread::current()) {
487 if (wait_for_suspend) {
488 // We are allowed to wait for the external suspend to complete
489 // so give the other thread a chance to get suspended.
490 if (!thr->wait_for_ext_suspend_completion(SuspendRetryCount,
491 SuspendRetryDelay, bits)) {
492 // didn't make it so let the caller know
493 return false;
494 }
495 }
496 // We aren't allowed to wait for the external suspend to complete
497 // so if the other thread isn't externally suspended we need to
498 // let the caller know.
499 else if (!thr->is_ext_suspend_completed_with_lock(bits)) {
500 return false;
501 }
502 }
504 return true;
505 }
508 // In the fullness of time, all users of the method should instead
509 // directly use allocate, besides being cleaner and faster, this will
510 // mean much better out of memory handling
511 unsigned char *
512 JvmtiEnvBase::jvmtiMalloc(jlong size) {
513 unsigned char* mem;
514 jvmtiError result = allocate(size, &mem);
515 assert(result == JVMTI_ERROR_NONE, "Allocate failed");
516 return mem;
517 }
520 //
521 // Threads
522 //
524 jobject *
525 JvmtiEnvBase::new_jobjectArray(int length, Handle *handles) {
526 if (length == 0) {
527 return NULL;
528 }
530 jobject *objArray = (jobject *) jvmtiMalloc(sizeof(jobject) * length);
531 NULL_CHECK(objArray, NULL);
533 for (int i=0; i<length; i++) {
534 objArray[i] = jni_reference(handles[i]);
535 }
536 return objArray;
537 }
539 jthread *
540 JvmtiEnvBase::new_jthreadArray(int length, Handle *handles) {
541 return (jthread *) new_jobjectArray(length,handles);
542 }
544 jthreadGroup *
545 JvmtiEnvBase::new_jthreadGroupArray(int length, Handle *handles) {
546 return (jthreadGroup *) new_jobjectArray(length,handles);
547 }
550 JavaThread *
551 JvmtiEnvBase::get_JavaThread(jthread jni_thread) {
552 oop t = JNIHandles::resolve_external_guard(jni_thread);
553 if (t == NULL || !t->is_a(SystemDictionary::Thread_klass())) {
554 return NULL;
555 }
556 // The following returns NULL if the thread has not yet run or is in
557 // process of exiting
558 return java_lang_Thread::thread(t);
559 }
562 // return the vframe on the specified thread and depth, NULL if no such frame
563 vframe*
564 JvmtiEnvBase::vframeFor(JavaThread* java_thread, jint depth) {
565 if (!java_thread->has_last_Java_frame()) {
566 return NULL;
567 }
568 RegisterMap reg_map(java_thread);
569 vframe *vf = java_thread->last_java_vframe(®_map);
570 int d = 0;
571 while ((vf != NULL) && (d < depth)) {
572 vf = vf->java_sender();
573 d++;
574 }
575 return vf;
576 }
579 //
580 // utilities: JNI objects
581 //
584 jclass
585 JvmtiEnvBase::get_jni_class_non_null(Klass* k) {
586 assert(k != NULL, "k != NULL");
587 return (jclass)jni_reference(k->java_mirror());
588 }
590 //
591 // Field Information
592 //
594 bool
595 JvmtiEnvBase::get_field_descriptor(Klass* k, jfieldID field, fieldDescriptor* fd) {
596 if (!jfieldIDWorkaround::is_valid_jfieldID(k, field)) {
597 return false;
598 }
599 bool found = false;
600 if (jfieldIDWorkaround::is_static_jfieldID(field)) {
601 JNIid* id = jfieldIDWorkaround::from_static_jfieldID(field);
602 found = id->find_local_field(fd);
603 } else {
604 // Non-static field. The fieldID is really the offset of the field within the object.
605 int offset = jfieldIDWorkaround::from_instance_jfieldID(k, field);
606 found = InstanceKlass::cast(k)->find_field_from_offset(offset, false, fd);
607 }
608 return found;
609 }
611 //
612 // Object Monitor Information
613 //
615 //
616 // Count the number of objects for a lightweight monitor. The hobj
617 // parameter is object that owns the monitor so this routine will
618 // count the number of times the same object was locked by frames
619 // in java_thread.
620 //
621 jint
622 JvmtiEnvBase::count_locked_objects(JavaThread *java_thread, Handle hobj) {
623 jint ret = 0;
624 if (!java_thread->has_last_Java_frame()) {
625 return ret; // no Java frames so no monitors
626 }
628 ResourceMark rm;
629 HandleMark hm;
630 RegisterMap reg_map(java_thread);
632 for(javaVFrame *jvf=java_thread->last_java_vframe(®_map); jvf != NULL;
633 jvf = jvf->java_sender()) {
634 GrowableArray<MonitorInfo*>* mons = jvf->monitors();
635 if (!mons->is_empty()) {
636 for (int i = 0; i < mons->length(); i++) {
637 MonitorInfo *mi = mons->at(i);
638 if (mi->owner_is_scalar_replaced()) continue;
640 // see if owner of the monitor is our object
641 if (mi->owner() != NULL && mi->owner() == hobj()) {
642 ret++;
643 }
644 }
645 }
646 }
647 return ret;
648 }
652 jvmtiError
653 JvmtiEnvBase::get_current_contended_monitor(JavaThread *calling_thread, JavaThread *java_thread, jobject *monitor_ptr) {
654 #ifdef ASSERT
655 uint32_t debug_bits = 0;
656 #endif
657 assert((SafepointSynchronize::is_at_safepoint() ||
658 is_thread_fully_suspended(java_thread, false, &debug_bits)),
659 "at safepoint or target thread is suspended");
660 oop obj = NULL;
661 ObjectMonitor *mon = java_thread->current_waiting_monitor();
662 if (mon == NULL) {
663 // thread is not doing an Object.wait() call
664 mon = java_thread->current_pending_monitor();
665 if (mon != NULL) {
666 // The thread is trying to enter() or raw_enter() an ObjectMonitor.
667 obj = (oop)mon->object();
668 // If obj == NULL, then ObjectMonitor is raw which doesn't count
669 // as contended for this API
670 }
671 // implied else: no contended ObjectMonitor
672 } else {
673 // thread is doing an Object.wait() call
674 obj = (oop)mon->object();
675 assert(obj != NULL, "Object.wait() should have an object");
676 }
678 if (obj == NULL) {
679 *monitor_ptr = NULL;
680 } else {
681 HandleMark hm;
682 Handle hobj(obj);
683 *monitor_ptr = jni_reference(calling_thread, hobj);
684 }
685 return JVMTI_ERROR_NONE;
686 }
689 jvmtiError
690 JvmtiEnvBase::get_owned_monitors(JavaThread *calling_thread, JavaThread* java_thread,
691 GrowableArray<jvmtiMonitorStackDepthInfo*> *owned_monitors_list) {
692 jvmtiError err = JVMTI_ERROR_NONE;
693 #ifdef ASSERT
694 uint32_t debug_bits = 0;
695 #endif
696 assert((SafepointSynchronize::is_at_safepoint() ||
697 is_thread_fully_suspended(java_thread, false, &debug_bits)),
698 "at safepoint or target thread is suspended");
700 if (java_thread->has_last_Java_frame()) {
701 ResourceMark rm;
702 HandleMark hm;
703 RegisterMap reg_map(java_thread);
705 int depth = 0;
706 for (javaVFrame *jvf = java_thread->last_java_vframe(®_map); jvf != NULL;
707 jvf = jvf->java_sender()) {
708 if (depth++ < MaxJavaStackTraceDepth) { // check for stack too deep
709 // add locked objects for this frame into list
710 err = get_locked_objects_in_frame(calling_thread, java_thread, jvf, owned_monitors_list, depth-1);
711 if (err != JVMTI_ERROR_NONE) {
712 return err;
713 }
714 }
715 }
716 }
718 // Get off stack monitors. (e.g. acquired via jni MonitorEnter).
719 JvmtiMonitorClosure jmc(java_thread, calling_thread, owned_monitors_list, this);
720 ObjectSynchronizer::monitors_iterate(&jmc);
721 err = jmc.error();
723 return err;
724 }
726 // Save JNI local handles for any objects that this frame owns.
727 jvmtiError
728 JvmtiEnvBase::get_locked_objects_in_frame(JavaThread* calling_thread, JavaThread* java_thread,
729 javaVFrame *jvf, GrowableArray<jvmtiMonitorStackDepthInfo*>* owned_monitors_list, int stack_depth) {
730 jvmtiError err = JVMTI_ERROR_NONE;
731 ResourceMark rm;
733 GrowableArray<MonitorInfo*>* mons = jvf->monitors();
734 if (mons->is_empty()) {
735 return err; // this javaVFrame holds no monitors
736 }
738 HandleMark hm;
739 oop wait_obj = NULL;
740 {
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 // save object of current enter() call (if any) for later comparison
750 ObjectMonitor *mon = java_thread->current_pending_monitor();
751 if (mon != NULL) {
752 pending_obj = (oop)mon->object();
753 }
754 }
756 for (int i = 0; i < mons->length(); i++) {
757 MonitorInfo *mi = mons->at(i);
759 if (mi->owner_is_scalar_replaced()) continue;
761 oop obj = mi->owner();
762 if (obj == NULL) {
763 // this monitor doesn't have an owning object so skip it
764 continue;
765 }
767 if (wait_obj == obj) {
768 // the thread is waiting on this monitor so it isn't really owned
769 continue;
770 }
772 if (pending_obj == obj) {
773 // the thread is pending on this monitor so it isn't really owned
774 continue;
775 }
777 if (owned_monitors_list->length() > 0) {
778 // Our list has at least one object on it so we have to check
779 // for recursive object locking
780 bool found = false;
781 for (int j = 0; j < owned_monitors_list->length(); j++) {
782 jobject jobj = ((jvmtiMonitorStackDepthInfo*)owned_monitors_list->at(j))->monitor;
783 oop check = JNIHandles::resolve(jobj);
784 if (check == obj) {
785 found = true; // we found the object
786 break;
787 }
788 }
790 if (found) {
791 // already have this object so don't include it
792 continue;
793 }
794 }
796 // add the owning object to our list
797 jvmtiMonitorStackDepthInfo *jmsdi;
798 err = allocate(sizeof(jvmtiMonitorStackDepthInfo), (unsigned char **)&jmsdi);
799 if (err != JVMTI_ERROR_NONE) {
800 return err;
801 }
802 Handle hobj(obj);
803 jmsdi->monitor = jni_reference(calling_thread, hobj);
804 jmsdi->stack_depth = stack_depth;
805 owned_monitors_list->append(jmsdi);
806 }
808 return err;
809 }
811 jvmtiError
812 JvmtiEnvBase::get_stack_trace(JavaThread *java_thread,
813 jint start_depth, jint max_count,
814 jvmtiFrameInfo* frame_buffer, jint* count_ptr) {
815 #ifdef ASSERT
816 uint32_t debug_bits = 0;
817 #endif
818 assert((SafepointSynchronize::is_at_safepoint() ||
819 is_thread_fully_suspended(java_thread, false, &debug_bits)),
820 "at safepoint or target thread is suspended");
821 int count = 0;
822 if (java_thread->has_last_Java_frame()) {
823 RegisterMap reg_map(java_thread);
824 Thread* current_thread = Thread::current();
825 ResourceMark rm(current_thread);
826 javaVFrame *jvf = java_thread->last_java_vframe(®_map);
827 HandleMark hm(current_thread);
828 if (start_depth != 0) {
829 if (start_depth > 0) {
830 for (int j = 0; j < start_depth && jvf != NULL; j++) {
831 jvf = jvf->java_sender();
832 }
833 if (jvf == NULL) {
834 // start_depth is deeper than the stack depth
835 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
836 }
837 } else { // start_depth < 0
838 // we are referencing the starting depth based on the oldest
839 // part of the stack.
840 // optimize to limit the number of times that java_sender() is called
841 javaVFrame *jvf_cursor = jvf;
842 javaVFrame *jvf_prev = NULL;
843 javaVFrame *jvf_prev_prev;
844 int j = 0;
845 while (jvf_cursor != NULL) {
846 jvf_prev_prev = jvf_prev;
847 jvf_prev = jvf_cursor;
848 for (j = 0; j > start_depth && jvf_cursor != NULL; j--) {
849 jvf_cursor = jvf_cursor->java_sender();
850 }
851 }
852 if (j == start_depth) {
853 // previous pointer is exactly where we want to start
854 jvf = jvf_prev;
855 } else {
856 // we need to back up further to get to the right place
857 if (jvf_prev_prev == NULL) {
858 // the -start_depth is greater than the stack depth
859 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
860 }
861 // j now is the number of frames on the stack starting with
862 // jvf_prev, we start from jvf_prev_prev and move older on
863 // the stack that many, the result is -start_depth frames
864 // remaining.
865 jvf = jvf_prev_prev;
866 for (; j < 0; j++) {
867 jvf = jvf->java_sender();
868 }
869 }
870 }
871 }
872 for (; count < max_count && jvf != NULL; count++) {
873 frame_buffer[count].method = jvf->method()->jmethod_id();
874 frame_buffer[count].location = (jvf->method()->is_native() ? -1 : jvf->bci());
875 jvf = jvf->java_sender();
876 }
877 } else {
878 if (start_depth != 0) {
879 // no frames and there is a starting depth
880 return JVMTI_ERROR_ILLEGAL_ARGUMENT;
881 }
882 }
883 *count_ptr = count;
884 return JVMTI_ERROR_NONE;
885 }
887 jvmtiError
888 JvmtiEnvBase::get_frame_count(JvmtiThreadState *state, jint *count_ptr) {
889 assert((state != NULL),
890 "JavaThread should create JvmtiThreadState before calling this method");
891 *count_ptr = state->count_frames();
892 return JVMTI_ERROR_NONE;
893 }
895 jvmtiError
896 JvmtiEnvBase::get_frame_location(JavaThread *java_thread, jint depth,
897 jmethodID* method_ptr, jlocation* location_ptr) {
898 #ifdef ASSERT
899 uint32_t debug_bits = 0;
900 #endif
901 assert((SafepointSynchronize::is_at_safepoint() ||
902 is_thread_fully_suspended(java_thread, false, &debug_bits)),
903 "at safepoint or target thread is suspended");
904 Thread* current_thread = Thread::current();
905 ResourceMark rm(current_thread);
907 vframe *vf = vframeFor(java_thread, depth);
908 if (vf == NULL) {
909 return JVMTI_ERROR_NO_MORE_FRAMES;
910 }
912 // vframeFor should return a java frame. If it doesn't
913 // it means we've got an internal error and we return the
914 // error in product mode. In debug mode we will instead
915 // attempt to cast the vframe to a javaVFrame and will
916 // cause an assertion/crash to allow further diagnosis.
917 #ifdef PRODUCT
918 if (!vf->is_java_frame()) {
919 return JVMTI_ERROR_INTERNAL;
920 }
921 #endif
923 HandleMark hm(current_thread);
924 javaVFrame *jvf = javaVFrame::cast(vf);
925 Method* method = jvf->method();
926 if (method->is_native()) {
927 *location_ptr = -1;
928 } else {
929 *location_ptr = jvf->bci();
930 }
931 *method_ptr = method->jmethod_id();
933 return JVMTI_ERROR_NONE;
934 }
937 jvmtiError
938 JvmtiEnvBase::get_object_monitor_usage(JavaThread* calling_thread, jobject object, jvmtiMonitorUsage* info_ptr) {
939 HandleMark hm;
940 Handle hobj;
942 bool at_safepoint = SafepointSynchronize::is_at_safepoint();
944 // Check arguments
945 {
946 oop mirror = JNIHandles::resolve_external_guard(object);
947 NULL_CHECK(mirror, JVMTI_ERROR_INVALID_OBJECT);
948 NULL_CHECK(info_ptr, JVMTI_ERROR_NULL_POINTER);
950 hobj = Handle(mirror);
951 }
953 JavaThread *owning_thread = NULL;
954 ObjectMonitor *mon = NULL;
955 jvmtiMonitorUsage ret = {
956 NULL, 0, 0, NULL, 0, NULL
957 };
959 uint32_t debug_bits = 0;
960 // first derive the object's owner and entry_count (if any)
961 {
962 // Revoke any biases before querying the mark word
963 if (SafepointSynchronize::is_at_safepoint()) {
964 BiasedLocking::revoke_at_safepoint(hobj);
965 } else {
966 BiasedLocking::revoke_and_rebias(hobj, false, calling_thread);
967 }
969 address owner = NULL;
970 {
971 markOop mark = hobj()->mark();
973 if (!mark->has_monitor()) {
974 // this object has a lightweight monitor
976 if (mark->has_locker()) {
977 owner = (address)mark->locker(); // save the address of the Lock word
978 }
979 // implied else: no owner
980 } else {
981 // this object has a heavyweight monitor
982 mon = mark->monitor();
984 // The owner field of a heavyweight monitor may be NULL for no
985 // owner, a JavaThread * or it may still be the address of the
986 // Lock word in a JavaThread's stack. A monitor can be inflated
987 // by a non-owning JavaThread, but only the owning JavaThread
988 // can change the owner field from the Lock word to the
989 // JavaThread * and it may not have done that yet.
990 owner = (address)mon->owner();
991 }
992 }
994 if (owner != NULL) {
995 // This monitor is owned so we have to find the owning JavaThread.
996 // Since owning_thread_from_monitor_owner() grabs a lock, GC can
997 // move our object at this point. However, our owner value is safe
998 // since it is either the Lock word on a stack or a JavaThread *.
999 owning_thread = Threads::owning_thread_from_monitor_owner(owner, !at_safepoint);
1000 // Cannot assume (owning_thread != NULL) here because this function
1001 // may not have been called at a safepoint and the owning_thread
1002 // might not be suspended.
1003 if (owning_thread != NULL) {
1004 // The monitor's owner either has to be the current thread, at safepoint
1005 // or it has to be suspended. Any of these conditions will prevent both
1006 // contending and waiting threads from modifying the state of
1007 // the monitor.
1008 if (!at_safepoint && !JvmtiEnv::is_thread_fully_suspended(owning_thread, true, &debug_bits)) {
1009 // Don't worry! This return of JVMTI_ERROR_THREAD_NOT_SUSPENDED
1010 // will not make it back to the JVM/TI agent. The error code will
1011 // get intercepted in JvmtiEnv::GetObjectMonitorUsage() which
1012 // will retry the call via a VM_GetObjectMonitorUsage VM op.
1013 return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
1014 }
1015 HandleMark hm;
1016 Handle th(owning_thread->threadObj());
1017 ret.owner = (jthread)jni_reference(calling_thread, th);
1018 }
1019 // implied else: no owner
1020 }
1022 if (owning_thread != NULL) { // monitor is owned
1023 if ((address)owning_thread == owner) {
1024 // the owner field is the JavaThread *
1025 assert(mon != NULL,
1026 "must have heavyweight monitor with JavaThread * owner");
1027 ret.entry_count = mon->recursions() + 1;
1028 } else {
1029 // The owner field is the Lock word on the JavaThread's stack
1030 // so the recursions field is not valid. We have to count the
1031 // number of recursive monitor entries the hard way. We pass
1032 // a handle to survive any GCs along the way.
1033 ResourceMark rm;
1034 ret.entry_count = count_locked_objects(owning_thread, hobj);
1035 }
1036 }
1037 // implied else: entry_count == 0
1038 }
1040 int nWant,nWait;
1041 if (mon != NULL) {
1042 // this object has a heavyweight monitor
1043 nWant = mon->contentions(); // # of threads contending for monitor
1044 nWait = mon->waiters(); // # of threads in Object.wait()
1045 ret.waiter_count = nWant + nWait;
1046 ret.notify_waiter_count = nWait;
1047 } else {
1048 // this object has a lightweight monitor
1049 ret.waiter_count = 0;
1050 ret.notify_waiter_count = 0;
1051 }
1053 // Allocate memory for heavyweight and lightweight monitor.
1054 jvmtiError err;
1055 err = allocate(ret.waiter_count * sizeof(jthread *), (unsigned char**)&ret.waiters);
1056 if (err != JVMTI_ERROR_NONE) {
1057 return err;
1058 }
1059 err = allocate(ret.notify_waiter_count * sizeof(jthread *),
1060 (unsigned char**)&ret.notify_waiters);
1061 if (err != JVMTI_ERROR_NONE) {
1062 deallocate((unsigned char*)ret.waiters);
1063 return err;
1064 }
1066 // now derive the rest of the fields
1067 if (mon != NULL) {
1068 // this object has a heavyweight monitor
1070 // Number of waiters may actually be less than the waiter count.
1071 // So NULL out memory so that unused memory will be NULL.
1072 memset(ret.waiters, 0, ret.waiter_count * sizeof(jthread *));
1073 memset(ret.notify_waiters, 0, ret.notify_waiter_count * sizeof(jthread *));
1075 if (ret.waiter_count > 0) {
1076 // we have contending and/or waiting threads
1077 HandleMark hm;
1078 if (nWant > 0) {
1079 // we have contending threads
1080 ResourceMark rm;
1081 // get_pending_threads returns only java thread so we do not need to
1082 // check for non java threads.
1083 GrowableArray<JavaThread*>* wantList = Threads::get_pending_threads(
1084 nWant, (address)mon, !at_safepoint);
1085 if (wantList->length() < nWant) {
1086 // robustness: the pending list has gotten smaller
1087 nWant = wantList->length();
1088 }
1089 for (int i = 0; i < nWant; i++) {
1090 JavaThread *pending_thread = wantList->at(i);
1091 // If the monitor has no owner, then a non-suspended contending
1092 // thread could potentially change the state of the monitor by
1093 // entering it. The JVM/TI spec doesn't allow this.
1094 if (owning_thread == NULL && !at_safepoint &
1095 !JvmtiEnv::is_thread_fully_suspended(pending_thread, true, &debug_bits)) {
1096 if (ret.owner != NULL) {
1097 destroy_jni_reference(calling_thread, ret.owner);
1098 }
1099 for (int j = 0; j < i; j++) {
1100 destroy_jni_reference(calling_thread, ret.waiters[j]);
1101 }
1102 deallocate((unsigned char*)ret.waiters);
1103 deallocate((unsigned char*)ret.notify_waiters);
1104 return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
1105 }
1106 Handle th(pending_thread->threadObj());
1107 ret.waiters[i] = (jthread)jni_reference(calling_thread, th);
1108 }
1109 }
1110 if (nWait > 0) {
1111 // we have threads in Object.wait()
1112 int offset = nWant; // add after any contending threads
1113 ObjectWaiter *waiter = mon->first_waiter();
1114 for (int i = 0, j = 0; i < nWait; i++) {
1115 if (waiter == NULL) {
1116 // robustness: the waiting list has gotten smaller
1117 nWait = j;
1118 break;
1119 }
1120 Thread *t = mon->thread_of_waiter(waiter);
1121 if (t != NULL && t->is_Java_thread()) {
1122 JavaThread *wjava_thread = (JavaThread *)t;
1123 // If the thread was found on the ObjectWaiter list, then
1124 // it has not been notified. This thread can't change the
1125 // state of the monitor so it doesn't need to be suspended.
1126 Handle th(wjava_thread->threadObj());
1127 ret.waiters[offset + j] = (jthread)jni_reference(calling_thread, th);
1128 ret.notify_waiters[j++] = (jthread)jni_reference(calling_thread, th);
1129 }
1130 waiter = mon->next_waiter(waiter);
1131 }
1132 }
1133 }
1135 // Adjust count. nWant and nWait count values may be less than original.
1136 ret.waiter_count = nWant + nWait;
1137 ret.notify_waiter_count = nWait;
1138 } else {
1139 // this object has a lightweight monitor and we have nothing more
1140 // to do here because the defaults are just fine.
1141 }
1143 // we don't update return parameter unless everything worked
1144 *info_ptr = ret;
1146 return JVMTI_ERROR_NONE;
1147 }
1149 ResourceTracker::ResourceTracker(JvmtiEnv* env) {
1150 _env = env;
1151 _allocations = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<unsigned char*>(20, true);
1152 _failed = false;
1153 }
1154 ResourceTracker::~ResourceTracker() {
1155 if (_failed) {
1156 for (int i=0; i<_allocations->length(); i++) {
1157 _env->deallocate(_allocations->at(i));
1158 }
1159 }
1160 delete _allocations;
1161 }
1163 jvmtiError ResourceTracker::allocate(jlong size, unsigned char** mem_ptr) {
1164 unsigned char *ptr;
1165 jvmtiError err = _env->allocate(size, &ptr);
1166 if (err == JVMTI_ERROR_NONE) {
1167 _allocations->append(ptr);
1168 *mem_ptr = ptr;
1169 } else {
1170 *mem_ptr = NULL;
1171 _failed = true;
1172 }
1173 return err;
1174 }
1176 unsigned char* ResourceTracker::allocate(jlong size) {
1177 unsigned char* ptr;
1178 allocate(size, &ptr);
1179 return ptr;
1180 }
1182 char* ResourceTracker::strdup(const char* str) {
1183 char *dup_str = (char*)allocate(strlen(str)+1);
1184 if (dup_str != NULL) {
1185 strcpy(dup_str, str);
1186 }
1187 return dup_str;
1188 }
1190 struct StackInfoNode {
1191 struct StackInfoNode *next;
1192 jvmtiStackInfo info;
1193 };
1195 // Create a jvmtiStackInfo inside a linked list node and create a
1196 // buffer for the frame information, both allocated as resource objects.
1197 // Fill in both the jvmtiStackInfo and the jvmtiFrameInfo.
1198 // Note that either or both of thr and thread_oop
1199 // may be null if the thread is new or has exited.
1200 void
1201 VM_GetMultipleStackTraces::fill_frames(jthread jt, JavaThread *thr, oop thread_oop) {
1202 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1204 jint state = 0;
1205 struct StackInfoNode *node = NEW_RESOURCE_OBJ(struct StackInfoNode);
1206 jvmtiStackInfo *infop = &(node->info);
1207 node->next = head();
1208 set_head(node);
1209 infop->frame_count = 0;
1210 infop->thread = jt;
1212 if (thread_oop != NULL) {
1213 // get most state bits
1214 state = (jint)java_lang_Thread::get_thread_status(thread_oop);
1215 }
1217 if (thr != NULL) { // add more state bits if there is a JavaThead to query
1218 // same as is_being_ext_suspended() but without locking
1219 if (thr->is_ext_suspended() || thr->is_external_suspend()) {
1220 state |= JVMTI_THREAD_STATE_SUSPENDED;
1221 }
1222 JavaThreadState jts = thr->thread_state();
1223 if (jts == _thread_in_native) {
1224 state |= JVMTI_THREAD_STATE_IN_NATIVE;
1225 }
1226 OSThread* osThread = thr->osthread();
1227 if (osThread != NULL && osThread->interrupted()) {
1228 state |= JVMTI_THREAD_STATE_INTERRUPTED;
1229 }
1230 }
1231 infop->state = state;
1233 if (thr != NULL || (state & JVMTI_THREAD_STATE_ALIVE) != 0) {
1234 infop->frame_buffer = NEW_RESOURCE_ARRAY(jvmtiFrameInfo, max_frame_count());
1235 env()->get_stack_trace(thr, 0, max_frame_count(),
1236 infop->frame_buffer, &(infop->frame_count));
1237 } else {
1238 infop->frame_buffer = NULL;
1239 infop->frame_count = 0;
1240 }
1241 _frame_count_total += infop->frame_count;
1242 }
1244 // Based on the stack information in the linked list, allocate memory
1245 // block to return and fill it from the info in the linked list.
1246 void
1247 VM_GetMultipleStackTraces::allocate_and_fill_stacks(jint thread_count) {
1248 // do I need to worry about alignment issues?
1249 jlong alloc_size = thread_count * sizeof(jvmtiStackInfo)
1250 + _frame_count_total * sizeof(jvmtiFrameInfo);
1251 env()->allocate(alloc_size, (unsigned char **)&_stack_info);
1253 // pointers to move through the newly allocated space as it is filled in
1254 jvmtiStackInfo *si = _stack_info + thread_count; // bottom of stack info
1255 jvmtiFrameInfo *fi = (jvmtiFrameInfo *)si; // is the top of frame info
1257 // copy information in resource area into allocated buffer
1258 // insert stack info backwards since linked list is backwards
1259 // insert frame info forwards
1260 // walk the StackInfoNodes
1261 for (struct StackInfoNode *sin = head(); sin != NULL; sin = sin->next) {
1262 jint frame_count = sin->info.frame_count;
1263 size_t frames_size = frame_count * sizeof(jvmtiFrameInfo);
1264 --si;
1265 memcpy(si, &(sin->info), sizeof(jvmtiStackInfo));
1266 if (frames_size == 0) {
1267 si->frame_buffer = NULL;
1268 } else {
1269 memcpy(fi, sin->info.frame_buffer, frames_size);
1270 si->frame_buffer = fi; // point to the new allocated copy of the frames
1271 fi += frame_count;
1272 }
1273 }
1274 assert(si == _stack_info, "the last copied stack info must be the first record");
1275 assert((unsigned char *)fi == ((unsigned char *)_stack_info) + alloc_size,
1276 "the last copied frame info must be the last record");
1277 }
1280 void
1281 VM_GetThreadListStackTraces::doit() {
1282 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1284 ResourceMark rm;
1285 for (int i = 0; i < _thread_count; ++i) {
1286 jthread jt = _thread_list[i];
1287 oop thread_oop = JNIHandles::resolve_external_guard(jt);
1288 if (thread_oop == NULL || !thread_oop->is_a(SystemDictionary::Thread_klass())) {
1289 set_result(JVMTI_ERROR_INVALID_THREAD);
1290 return;
1291 }
1292 fill_frames(jt, java_lang_Thread::thread(thread_oop), thread_oop);
1293 }
1294 allocate_and_fill_stacks(_thread_count);
1295 }
1297 void
1298 VM_GetAllStackTraces::doit() {
1299 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
1301 ResourceMark rm;
1302 _final_thread_count = 0;
1303 for (JavaThread *jt = Threads::first(); jt != NULL; jt = jt->next()) {
1304 oop thread_oop = jt->threadObj();
1305 if (thread_oop != NULL &&
1306 !jt->is_exiting() &&
1307 java_lang_Thread::is_alive(thread_oop) &&
1308 !jt->is_hidden_from_external_view()) {
1309 ++_final_thread_count;
1310 // Handle block of the calling thread is used to create local refs.
1311 fill_frames((jthread)JNIHandles::make_local(_calling_thread, thread_oop),
1312 jt, thread_oop);
1313 }
1314 }
1315 allocate_and_fill_stacks(_final_thread_count);
1316 }
1318 // Verifies that the top frame is a java frame in an expected state.
1319 // Deoptimizes frame if needed.
1320 // Checks that the frame method signature matches the return type (tos).
1321 // HandleMark must be defined in the caller only.
1322 // It is to keep a ret_ob_h handle alive after return to the caller.
1323 jvmtiError
1324 JvmtiEnvBase::check_top_frame(JavaThread* current_thread, JavaThread* java_thread,
1325 jvalue value, TosState tos, Handle* ret_ob_h) {
1326 ResourceMark rm(current_thread);
1328 vframe *vf = vframeFor(java_thread, 0);
1329 NULL_CHECK(vf, JVMTI_ERROR_NO_MORE_FRAMES);
1331 javaVFrame *jvf = (javaVFrame*) vf;
1332 if (!vf->is_java_frame() || jvf->method()->is_native()) {
1333 return JVMTI_ERROR_OPAQUE_FRAME;
1334 }
1336 // If the frame is a compiled one, need to deoptimize it.
1337 if (vf->is_compiled_frame()) {
1338 if (!vf->fr().can_be_deoptimized()) {
1339 return JVMTI_ERROR_OPAQUE_FRAME;
1340 }
1341 Deoptimization::deoptimize_frame(java_thread, jvf->fr().id());
1342 }
1344 // Get information about method return type
1345 Symbol* signature = jvf->method()->signature();
1347 ResultTypeFinder rtf(signature);
1348 TosState fr_tos = as_TosState(rtf.type());
1349 if (fr_tos != tos) {
1350 if (tos != itos || (fr_tos != btos && fr_tos != ctos && fr_tos != stos)) {
1351 return JVMTI_ERROR_TYPE_MISMATCH;
1352 }
1353 }
1355 // Check that the jobject class matches the return type signature.
1356 jobject jobj = value.l;
1357 if (tos == atos && jobj != NULL) { // NULL reference is allowed
1358 Handle ob_h = Handle(current_thread, JNIHandles::resolve_external_guard(jobj));
1359 NULL_CHECK(ob_h, JVMTI_ERROR_INVALID_OBJECT);
1360 KlassHandle ob_kh = KlassHandle(current_thread, ob_h()->klass());
1361 NULL_CHECK(ob_kh, JVMTI_ERROR_INVALID_OBJECT);
1363 // Method return type signature.
1364 char* ty_sign = 1 + strchr(signature->as_C_string(), ')');
1366 if (!VM_GetOrSetLocal::is_assignable(ty_sign, ob_kh(), current_thread)) {
1367 return JVMTI_ERROR_TYPE_MISMATCH;
1368 }
1369 *ret_ob_h = ob_h;
1370 }
1371 return JVMTI_ERROR_NONE;
1372 } /* end check_top_frame */
1375 // ForceEarlyReturn<type> follows the PopFrame approach in many aspects.
1376 // Main difference is on the last stage in the interpreter.
1377 // The PopFrame stops method execution to continue execution
1378 // from the same method call instruction.
1379 // The ForceEarlyReturn forces return from method so the execution
1380 // continues at the bytecode following the method call.
1382 // Threads_lock NOT held, java_thread not protected by lock
1383 // java_thread - pre-checked
1385 jvmtiError
1386 JvmtiEnvBase::force_early_return(JavaThread* java_thread, jvalue value, TosState tos) {
1387 JavaThread* current_thread = JavaThread::current();
1388 HandleMark hm(current_thread);
1389 uint32_t debug_bits = 0;
1391 // retrieve or create the state
1392 JvmtiThreadState* state = JvmtiThreadState::state_for(java_thread);
1393 if (state == NULL) {
1394 return JVMTI_ERROR_THREAD_NOT_ALIVE;
1395 }
1397 // Check if java_thread is fully suspended
1398 if (!is_thread_fully_suspended(java_thread,
1399 true /* wait for suspend completion */,
1400 &debug_bits)) {
1401 return JVMTI_ERROR_THREAD_NOT_SUSPENDED;
1402 }
1404 // Check to see if a ForceEarlyReturn was already in progress
1405 if (state->is_earlyret_pending()) {
1406 // Probably possible for JVMTI clients to trigger this, but the
1407 // JPDA backend shouldn't allow this to happen
1408 return JVMTI_ERROR_INTERNAL;
1409 }
1410 {
1411 // The same as for PopFrame. Workaround bug:
1412 // 4812902: popFrame hangs if the method is waiting at a synchronize
1413 // Catch this condition and return an error to avoid hanging.
1414 // Now JVMTI spec allows an implementation to bail out with an opaque
1415 // frame error.
1416 OSThread* osThread = java_thread->osthread();
1417 if (osThread->get_state() == MONITOR_WAIT) {
1418 return JVMTI_ERROR_OPAQUE_FRAME;
1419 }
1420 }
1421 Handle ret_ob_h = Handle();
1422 jvmtiError err = check_top_frame(current_thread, java_thread, value, tos, &ret_ob_h);
1423 if (err != JVMTI_ERROR_NONE) {
1424 return err;
1425 }
1426 assert(tos != atos || value.l == NULL || ret_ob_h() != NULL,
1427 "return object oop must not be NULL if jobject is not NULL");
1429 // Update the thread state to reflect that the top frame must be
1430 // forced to return.
1431 // The current frame will be returned later when the suspended
1432 // thread is resumed and right before returning from VM to Java.
1433 // (see call_VM_base() in assembler_<cpu>.cpp).
1435 state->set_earlyret_pending();
1436 state->set_earlyret_oop(ret_ob_h());
1437 state->set_earlyret_value(value, tos);
1439 // Set pending step flag for this early return.
1440 // It is cleared when next step event is posted.
1441 state->set_pending_step_for_earlyret();
1443 return JVMTI_ERROR_NONE;
1444 } /* end force_early_return */
1446 void
1447 JvmtiMonitorClosure::do_monitor(ObjectMonitor* mon) {
1448 if ( _error != JVMTI_ERROR_NONE) {
1449 // Error occurred in previous iteration so no need to add
1450 // to the list.
1451 return;
1452 }
1453 if (mon->owner() == _java_thread ) {
1454 // Filter out on stack monitors collected during stack walk.
1455 oop obj = (oop)mon->object();
1456 bool found = false;
1457 for (int j = 0; j < _owned_monitors_list->length(); j++) {
1458 jobject jobj = ((jvmtiMonitorStackDepthInfo*)_owned_monitors_list->at(j))->monitor;
1459 oop check = JNIHandles::resolve(jobj);
1460 if (check == obj) {
1461 // On stack monitor already collected during the stack walk.
1462 found = true;
1463 break;
1464 }
1465 }
1466 if (found == false) {
1467 // This is off stack monitor (e.g. acquired via jni MonitorEnter).
1468 jvmtiError err;
1469 jvmtiMonitorStackDepthInfo *jmsdi;
1470 err = _env->allocate(sizeof(jvmtiMonitorStackDepthInfo), (unsigned char **)&jmsdi);
1471 if (err != JVMTI_ERROR_NONE) {
1472 _error = err;
1473 return;
1474 }
1475 Handle hobj(obj);
1476 jmsdi->monitor = _env->jni_reference(_calling_thread, hobj);
1477 // stack depth is unknown for this monitor.
1478 jmsdi->stack_depth = -1;
1479 _owned_monitors_list->append(jmsdi);
1480 }
1481 }
1482 }