1 /*
2 * Copyright (c) 2003, 2010, 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/systemDictionary.hpp"
27 #include "interpreter/interpreter.hpp"
28 #include "jvmtifiles/jvmtiEnv.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "oops/instanceKlass.hpp"
31 #include "prims/jvmtiAgentThread.hpp"
32 #include "prims/jvmtiEventController.inline.hpp"
33 #include "prims/jvmtiImpl.hpp"
34 #include "prims/jvmtiRedefineClasses.hpp"
35 #include "runtime/handles.hpp"
36 #include "runtime/handles.inline.hpp"
37 #include "runtime/interfaceSupport.hpp"
38 #include "runtime/javaCalls.hpp"
39 #include "runtime/signature.hpp"
40 #include "runtime/vframe.hpp"
41 #include "runtime/vframe_hp.hpp"
42 #include "runtime/vm_operations.hpp"
43 #include "utilities/exceptions.hpp"
44 #ifdef TARGET_OS_FAMILY_linux
45 # include "thread_linux.inline.hpp"
46 #endif
47 #ifdef TARGET_OS_FAMILY_solaris
48 # include "thread_solaris.inline.hpp"
49 #endif
50 #ifdef TARGET_OS_FAMILY_windows
51 # include "thread_windows.inline.hpp"
52 #endif
53
54 GrowableArray<JvmtiRawMonitor*> *JvmtiPendingMonitors::_monitors = new (ResourceObj::C_HEAP) GrowableArray<JvmtiRawMonitor*>(1,true);
55
56 void JvmtiPendingMonitors::transition_raw_monitors() {
57 assert((Threads::number_of_threads()==1),
58 "Java thread has not created yet or more than one java thread \
59 is running. Raw monitor transition will not work");
60 JavaThread *current_java_thread = JavaThread::current();
61 assert(current_java_thread->thread_state() == _thread_in_vm, "Must be in vm");
62 {
63 ThreadBlockInVM __tbivm(current_java_thread);
64 for(int i=0; i< count(); i++) {
65 JvmtiRawMonitor *rmonitor = monitors()->at(i);
66 int r = rmonitor->raw_enter(current_java_thread);
67 assert(r == ObjectMonitor::OM_OK, "raw_enter should have worked");
68 }
69 }
70 // pending monitors are converted to real monitor so delete them all.
71 dispose();
72 }
73
74 //
75 // class JvmtiAgentThread
76 //
77 // JavaThread used to wrap a thread started by an agent
78 // using the JVMTI method RunAgentThread.
79 //
80
81 JvmtiAgentThread::JvmtiAgentThread(JvmtiEnv* env, jvmtiStartFunction start_fn, const void *start_arg)
82 : JavaThread(start_function_wrapper) {
83 _env = env;
84 _start_fn = start_fn;
85 _start_arg = start_arg;
86 }
87
88 void
89 JvmtiAgentThread::start_function_wrapper(JavaThread *thread, TRAPS) {
90 // It is expected that any Agent threads will be created as
91 // Java Threads. If this is the case, notification of the creation
92 // of the thread is given in JavaThread::thread_main().
93 assert(thread->is_Java_thread(), "debugger thread should be a Java Thread");
94 assert(thread == JavaThread::current(), "sanity check");
95
96 JvmtiAgentThread *dthread = (JvmtiAgentThread *)thread;
97 dthread->call_start_function();
98 }
99
100 void
101 JvmtiAgentThread::call_start_function() {
102 ThreadToNativeFromVM transition(this);
103 _start_fn(_env->jvmti_external(), jni_environment(), (void*)_start_arg);
104 }
105
106
107 //
108 // class GrowableCache - private methods
109 //
110
111 void GrowableCache::recache() {
112 int len = _elements->length();
113
114 FREE_C_HEAP_ARRAY(address, _cache);
115 _cache = NEW_C_HEAP_ARRAY(address,len+1);
116
117 for (int i=0; i<len; i++) {
118 _cache[i] = _elements->at(i)->getCacheValue();
119 //
120 // The cache entry has gone bad. Without a valid frame pointer
121 // value, the entry is useless so we simply delete it in product
122 // mode. The call to remove() will rebuild the cache again
123 // without the bad entry.
124 //
125 if (_cache[i] == NULL) {
126 assert(false, "cannot recache NULL elements");
127 remove(i);
128 return;
129 }
130 }
131 _cache[len] = NULL;
132
133 _listener_fun(_this_obj,_cache);
134 }
135
136 bool GrowableCache::equals(void* v, GrowableElement *e2) {
137 GrowableElement *e1 = (GrowableElement *) v;
138 assert(e1 != NULL, "e1 != NULL");
139 assert(e2 != NULL, "e2 != NULL");
140
141 return e1->equals(e2);
142 }
143
144 //
145 // class GrowableCache - public methods
146 //
147
148 GrowableCache::GrowableCache() {
149 _this_obj = NULL;
150 _listener_fun = NULL;
151 _elements = NULL;
152 _cache = NULL;
153 }
154
155 GrowableCache::~GrowableCache() {
156 clear();
157 delete _elements;
158 FREE_C_HEAP_ARRAY(address, _cache);
159 }
160
161 void GrowableCache::initialize(void *this_obj, void listener_fun(void *, address*) ) {
162 _this_obj = this_obj;
163 _listener_fun = listener_fun;
164 _elements = new (ResourceObj::C_HEAP) GrowableArray<GrowableElement*>(5,true);
165 recache();
166 }
167
168 // number of elements in the collection
169 int GrowableCache::length() {
170 return _elements->length();
171 }
172
173 // get the value of the index element in the collection
174 GrowableElement* GrowableCache::at(int index) {
175 GrowableElement *e = (GrowableElement *) _elements->at(index);
176 assert(e != NULL, "e != NULL");
177 return e;
178 }
179
180 int GrowableCache::find(GrowableElement* e) {
181 return _elements->find(e, GrowableCache::equals);
182 }
183
184 // append a copy of the element to the end of the collection
185 void GrowableCache::append(GrowableElement* e) {
186 GrowableElement *new_e = e->clone();
187 _elements->append(new_e);
188 recache();
189 }
190
191 // insert a copy of the element using lessthan()
192 void GrowableCache::insert(GrowableElement* e) {
193 GrowableElement *new_e = e->clone();
194 _elements->append(new_e);
195
196 int n = length()-2;
197 for (int i=n; i>=0; i--) {
198 GrowableElement *e1 = _elements->at(i);
199 GrowableElement *e2 = _elements->at(i+1);
200 if (e2->lessThan(e1)) {
201 _elements->at_put(i+1, e1);
202 _elements->at_put(i, e2);
203 }
204 }
205
206 recache();
207 }
208
209 // remove the element at index
210 void GrowableCache::remove (int index) {
211 GrowableElement *e = _elements->at(index);
212 assert(e != NULL, "e != NULL");
213 _elements->remove(e);
214 delete e;
215 recache();
216 }
217
218 // clear out all elements, release all heap space and
219 // let our listener know that things have changed.
220 void GrowableCache::clear() {
221 int len = _elements->length();
222 for (int i=0; i<len; i++) {
223 delete _elements->at(i);
224 }
225 _elements->clear();
226 recache();
227 }
228
229 void GrowableCache::oops_do(OopClosure* f) {
230 int len = _elements->length();
231 for (int i=0; i<len; i++) {
232 GrowableElement *e = _elements->at(i);
233 e->oops_do(f);
234 }
235 }
236
237 void GrowableCache::gc_epilogue() {
238 int len = _elements->length();
239 // recompute the new cache value after GC
240 for (int i=0; i<len; i++) {
241 _cache[i] = _elements->at(i)->getCacheValue();
242 }
243 }
244
245
246 //
247 // class JvmtiRawMonitor
248 //
249
250 JvmtiRawMonitor::JvmtiRawMonitor(const char *name) {
251 #ifdef ASSERT
252 _name = strcpy(NEW_C_HEAP_ARRAY(char, strlen(name) + 1), name);
253 #else
254 _name = NULL;
255 #endif
256 _magic = JVMTI_RM_MAGIC;
257 }
258
259 JvmtiRawMonitor::~JvmtiRawMonitor() {
260 #ifdef ASSERT
261 FreeHeap(_name);
262 #endif
263 _magic = 0;
264 }
265
266
267 bool
268 JvmtiRawMonitor::is_valid() {
269 int value = 0;
270
271 // This object might not be a JvmtiRawMonitor so we can't assume
272 // the _magic field is properly aligned. Get the value in a safe
273 // way and then check against JVMTI_RM_MAGIC.
274
275 switch (sizeof(_magic)) {
276 case 2:
277 value = Bytes::get_native_u2((address)&_magic);
278 break;
279
280 case 4:
281 value = Bytes::get_native_u4((address)&_magic);
282 break;
283
284 case 8:
285 value = Bytes::get_native_u8((address)&_magic);
286 break;
287
288 default:
289 guarantee(false, "_magic field is an unexpected size");
290 }
291
292 return value == JVMTI_RM_MAGIC;
293 }
294
295
296 //
297 // class JvmtiBreakpoint
298 //
299
300 JvmtiBreakpoint::JvmtiBreakpoint() {
301 _method = NULL;
302 _bci = 0;
303 #ifdef CHECK_UNHANDLED_OOPS
304 // This one is always allocated with new, but check it just in case.
305 Thread *thread = Thread::current();
306 if (thread->is_in_stack((address)&_method)) {
307 thread->allow_unhandled_oop((oop*)&_method);
308 }
309 #endif // CHECK_UNHANDLED_OOPS
310 }
311
312 JvmtiBreakpoint::JvmtiBreakpoint(methodOop m_method, jlocation location) {
313 _method = m_method;
314 assert(_method != NULL, "_method != NULL");
315 _bci = (int) location;
316 #ifdef CHECK_UNHANDLED_OOPS
317 // Could be allocated with new and wouldn't be on the unhandled oop list.
318 Thread *thread = Thread::current();
319 if (thread->is_in_stack((address)&_method)) {
320 thread->allow_unhandled_oop(&_method);
321 }
322 #endif // CHECK_UNHANDLED_OOPS
323
324 assert(_bci >= 0, "_bci >= 0");
325 }
326
327 void JvmtiBreakpoint::copy(JvmtiBreakpoint& bp) {
328 _method = bp._method;
329 _bci = bp._bci;
330 }
331
332 bool JvmtiBreakpoint::lessThan(JvmtiBreakpoint& bp) {
333 Unimplemented();
334 return false;
335 }
336
337 bool JvmtiBreakpoint::equals(JvmtiBreakpoint& bp) {
338 return _method == bp._method
339 && _bci == bp._bci;
340 }
341
342 bool JvmtiBreakpoint::is_valid() {
343 return _method != NULL &&
344 _bci >= 0;
345 }
346
347 address JvmtiBreakpoint::getBcp() {
348 return _method->bcp_from(_bci);
349 }
350
351 void JvmtiBreakpoint::each_method_version_do(method_action meth_act) {
352 ((methodOopDesc*)_method->*meth_act)(_bci);
353
354 // add/remove breakpoint to/from versions of the method that
355 // are EMCP. Directly or transitively obsolete methods are
356 // not saved in the PreviousVersionInfo.
357 Thread *thread = Thread::current();
358 instanceKlassHandle ikh = instanceKlassHandle(thread, _method->method_holder());
359 symbolOop m_name = _method->name();
360 symbolOop m_signature = _method->signature();
361
362 {
363 ResourceMark rm(thread);
364 // PreviousVersionInfo objects returned via PreviousVersionWalker
365 // contain a GrowableArray of handles. We have to clean up the
366 // GrowableArray _after_ the PreviousVersionWalker destructor
367 // has destroyed the handles.
368 {
369 // search previous versions if they exist
370 PreviousVersionWalker pvw((instanceKlass *)ikh()->klass_part());
371 for (PreviousVersionInfo * pv_info = pvw.next_previous_version();
372 pv_info != NULL; pv_info = pvw.next_previous_version()) {
373 GrowableArray<methodHandle>* methods =
374 pv_info->prev_EMCP_method_handles();
375
376 if (methods == NULL) {
377 // We have run into a PreviousVersion generation where
378 // all methods were made obsolete during that generation's
379 // RedefineClasses() operation. At the time of that
380 // operation, all EMCP methods were flushed so we don't
381 // have to go back any further.
382 //
383 // A NULL methods array is different than an empty methods
384 // array. We cannot infer any optimizations about older
385 // generations from an empty methods array for the current
386 // generation.
387 break;
388 }
389
390 for (int i = methods->length() - 1; i >= 0; i--) {
391 methodHandle method = methods->at(i);
392 if (method->name() == m_name && method->signature() == m_signature) {
393 RC_TRACE(0x00000800, ("%sing breakpoint in %s(%s)",
394 meth_act == &methodOopDesc::set_breakpoint ? "sett" : "clear",
395 method->name()->as_C_string(),
396 method->signature()->as_C_string()));
397 assert(!method->is_obsolete(), "only EMCP methods here");
398
399 ((methodOopDesc*)method()->*meth_act)(_bci);
400 break;
401 }
402 }
403 }
404 } // pvw is cleaned up
405 } // rm is cleaned up
406 }
407
408 void JvmtiBreakpoint::set() {
409 each_method_version_do(&methodOopDesc::set_breakpoint);
410 }
411
412 void JvmtiBreakpoint::clear() {
413 each_method_version_do(&methodOopDesc::clear_breakpoint);
414 }
415
416 void JvmtiBreakpoint::print() {
417 #ifndef PRODUCT
418 const char *class_name = (_method == NULL) ? "NULL" : _method->klass_name()->as_C_string();
419 const char *method_name = (_method == NULL) ? "NULL" : _method->name()->as_C_string();
420
421 tty->print("Breakpoint(%s,%s,%d,%p)",class_name, method_name, _bci, getBcp());
422 #endif
423 }
424
425
426 //
427 // class VM_ChangeBreakpoints
428 //
429 // Modify the Breakpoints data structure at a safepoint
430 //
431
432 void VM_ChangeBreakpoints::doit() {
433 switch (_operation) {
434 case SET_BREAKPOINT:
435 _breakpoints->set_at_safepoint(*_bp);
436 break;
437 case CLEAR_BREAKPOINT:
438 _breakpoints->clear_at_safepoint(*_bp);
439 break;
440 case CLEAR_ALL_BREAKPOINT:
441 _breakpoints->clearall_at_safepoint();
442 break;
443 default:
444 assert(false, "Unknown operation");
445 }
446 }
447
448 void VM_ChangeBreakpoints::oops_do(OopClosure* f) {
449 // This operation keeps breakpoints alive
450 if (_breakpoints != NULL) {
451 _breakpoints->oops_do(f);
452 }
453 if (_bp != NULL) {
454 _bp->oops_do(f);
455 }
456 }
457
458 //
459 // class JvmtiBreakpoints
460 //
461 // a JVMTI internal collection of JvmtiBreakpoint
462 //
463
464 JvmtiBreakpoints::JvmtiBreakpoints(void listener_fun(void *,address *)) {
465 _bps.initialize(this,listener_fun);
466 }
467
468 JvmtiBreakpoints:: ~JvmtiBreakpoints() {}
469
470 void JvmtiBreakpoints::oops_do(OopClosure* f) {
471 _bps.oops_do(f);
472 }
473
474 void JvmtiBreakpoints::gc_epilogue() {
475 _bps.gc_epilogue();
476 }
477
478 void JvmtiBreakpoints::print() {
479 #ifndef PRODUCT
480 ResourceMark rm;
481
482 int n = _bps.length();
483 for (int i=0; i<n; i++) {
484 JvmtiBreakpoint& bp = _bps.at(i);
485 tty->print("%d: ", i);
486 bp.print();
487 tty->print_cr("");
488 }
489 #endif
490 }
491
492
493 void JvmtiBreakpoints::set_at_safepoint(JvmtiBreakpoint& bp) {
494 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
495
496 int i = _bps.find(bp);
497 if (i == -1) {
498 _bps.append(bp);
499 bp.set();
500 }
501 }
502
503 void JvmtiBreakpoints::clear_at_safepoint(JvmtiBreakpoint& bp) {
504 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
505
506 int i = _bps.find(bp);
507 if (i != -1) {
508 _bps.remove(i);
509 bp.clear();
510 }
511 }
512
513 void JvmtiBreakpoints::clearall_at_safepoint() {
514 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
515
516 int len = _bps.length();
517 for (int i=0; i<len; i++) {
518 _bps.at(i).clear();
519 }
520 _bps.clear();
521 }
522
523 int JvmtiBreakpoints::length() { return _bps.length(); }
524
525 int JvmtiBreakpoints::set(JvmtiBreakpoint& bp) {
526 if ( _bps.find(bp) != -1) {
527 return JVMTI_ERROR_DUPLICATE;
528 }
529 VM_ChangeBreakpoints set_breakpoint(this,VM_ChangeBreakpoints::SET_BREAKPOINT, &bp);
530 VMThread::execute(&set_breakpoint);
531 return JVMTI_ERROR_NONE;
532 }
533
534 int JvmtiBreakpoints::clear(JvmtiBreakpoint& bp) {
535 if ( _bps.find(bp) == -1) {
536 return JVMTI_ERROR_NOT_FOUND;
537 }
538
539 VM_ChangeBreakpoints clear_breakpoint(this,VM_ChangeBreakpoints::CLEAR_BREAKPOINT, &bp);
540 VMThread::execute(&clear_breakpoint);
541 return JVMTI_ERROR_NONE;
542 }
543
544 void JvmtiBreakpoints::clearall_in_class_at_safepoint(klassOop klass) {
545 bool changed = true;
546 // We are going to run thru the list of bkpts
547 // and delete some. This deletion probably alters
548 // the list in some implementation defined way such
549 // that when we delete entry i, the next entry might
550 // no longer be at i+1. To be safe, each time we delete
551 // an entry, we'll just start again from the beginning.
552 // We'll stop when we make a pass thru the whole list without
553 // deleting anything.
554 while (changed) {
555 int len = _bps.length();
556 changed = false;
557 for (int i = 0; i < len; i++) {
558 JvmtiBreakpoint& bp = _bps.at(i);
559 if (bp.method()->method_holder() == klass) {
560 bp.clear();
561 _bps.remove(i);
562 // This changed 'i' so we have to start over.
563 changed = true;
564 break;
565 }
566 }
567 }
568 }
569
570 void JvmtiBreakpoints::clearall() {
571 VM_ChangeBreakpoints clearall_breakpoint(this,VM_ChangeBreakpoints::CLEAR_ALL_BREAKPOINT);
572 VMThread::execute(&clearall_breakpoint);
573 }
574
575 //
576 // class JvmtiCurrentBreakpoints
577 //
578
579 JvmtiBreakpoints *JvmtiCurrentBreakpoints::_jvmti_breakpoints = NULL;
580 address * JvmtiCurrentBreakpoints::_breakpoint_list = NULL;
581
582
583 JvmtiBreakpoints& JvmtiCurrentBreakpoints::get_jvmti_breakpoints() {
584 if (_jvmti_breakpoints != NULL) return (*_jvmti_breakpoints);
585 _jvmti_breakpoints = new JvmtiBreakpoints(listener_fun);
586 assert(_jvmti_breakpoints != NULL, "_jvmti_breakpoints != NULL");
587 return (*_jvmti_breakpoints);
588 }
589
590 void JvmtiCurrentBreakpoints::listener_fun(void *this_obj, address *cache) {
591 JvmtiBreakpoints *this_jvmti = (JvmtiBreakpoints *) this_obj;
592 assert(this_jvmti != NULL, "this_jvmti != NULL");
593
594 debug_only(int n = this_jvmti->length(););
595 assert(cache[n] == NULL, "cache must be NULL terminated");
596
597 set_breakpoint_list(cache);
598 }
599
600
601 void JvmtiCurrentBreakpoints::oops_do(OopClosure* f) {
602 if (_jvmti_breakpoints != NULL) {
603 _jvmti_breakpoints->oops_do(f);
604 }
605 }
606
607 void JvmtiCurrentBreakpoints::gc_epilogue() {
608 if (_jvmti_breakpoints != NULL) {
609 _jvmti_breakpoints->gc_epilogue();
610 }
611 }
612
613
614 ///////////////////////////////////////////////////////////////
615 //
616 // class VM_GetOrSetLocal
617 //
618
619 // Constructor for non-object getter
620 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, int index, BasicType type)
621 : _thread(thread)
622 , _calling_thread(NULL)
623 , _depth(depth)
624 , _index(index)
625 , _type(type)
626 , _set(false)
627 , _jvf(NULL)
628 , _result(JVMTI_ERROR_NONE)
629 {
630 }
631
632 // Constructor for object or non-object setter
633 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, int index, BasicType type, jvalue value)
634 : _thread(thread)
635 , _calling_thread(NULL)
636 , _depth(depth)
637 , _index(index)
638 , _type(type)
639 , _value(value)
640 , _set(true)
641 , _jvf(NULL)
642 , _result(JVMTI_ERROR_NONE)
643 {
644 }
645
646 // Constructor for object getter
647 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, JavaThread* calling_thread, jint depth, int index)
648 : _thread(thread)
649 , _calling_thread(calling_thread)
650 , _depth(depth)
651 , _index(index)
652 , _type(T_OBJECT)
653 , _set(false)
654 , _jvf(NULL)
655 , _result(JVMTI_ERROR_NONE)
656 {
657 }
658
659
660 vframe *VM_GetOrSetLocal::get_vframe() {
661 if (!_thread->has_last_Java_frame()) {
662 return NULL;
663 }
664 RegisterMap reg_map(_thread);
665 vframe *vf = _thread->last_java_vframe(®_map);
666 int d = 0;
667 while ((vf != NULL) && (d < _depth)) {
668 vf = vf->java_sender();
669 d++;
670 }
671 return vf;
672 }
673
674 javaVFrame *VM_GetOrSetLocal::get_java_vframe() {
675 vframe* vf = get_vframe();
676 if (vf == NULL) {
677 _result = JVMTI_ERROR_NO_MORE_FRAMES;
678 return NULL;
679 }
680 javaVFrame *jvf = (javaVFrame*)vf;
681
682 if (!vf->is_java_frame() || jvf->method()->is_native()) {
683 _result = JVMTI_ERROR_OPAQUE_FRAME;
684 return NULL;
685 }
686 return jvf;
687 }
688
689 // Check that the klass is assignable to a type with the given signature.
690 // Another solution could be to use the function Klass::is_subtype_of(type).
691 // But the type class can be forced to load/initialize eagerly in such a case.
692 // This may cause unexpected consequences like CFLH or class-init JVMTI events.
693 // It is better to avoid such a behavior.
694 bool VM_GetOrSetLocal::is_assignable(const char* ty_sign, Klass* klass, Thread* thread) {
695 assert(ty_sign != NULL, "type signature must not be NULL");
696 assert(thread != NULL, "thread must not be NULL");
697 assert(klass != NULL, "klass must not be NULL");
698
699 int len = (int) strlen(ty_sign);
700 if (ty_sign[0] == 'L' && ty_sign[len-1] == ';') { // Need pure class/interface name
701 ty_sign++;
702 len -= 2;
703 }
704 symbolHandle ty_sym = oopFactory::new_symbol_handle(ty_sign, len, thread);
705 if (klass->name() == ty_sym()) {
706 return true;
707 }
708 // Compare primary supers
709 int super_depth = klass->super_depth();
710 int idx;
711 for (idx = 0; idx < super_depth; idx++) {
712 if (Klass::cast(klass->primary_super_of_depth(idx))->name() == ty_sym()) {
713 return true;
714 }
715 }
716 // Compare secondary supers
717 objArrayOop sec_supers = klass->secondary_supers();
718 for (idx = 0; idx < sec_supers->length(); idx++) {
719 if (Klass::cast((klassOop) sec_supers->obj_at(idx))->name() == ty_sym()) {
720 return true;
721 }
722 }
723 return false;
724 }
725
726 // Checks error conditions:
727 // JVMTI_ERROR_INVALID_SLOT
728 // JVMTI_ERROR_TYPE_MISMATCH
729 // Returns: 'true' - everything is Ok, 'false' - error code
730
731 bool VM_GetOrSetLocal::check_slot_type(javaVFrame* jvf) {
732 methodOop method_oop = jvf->method();
733 if (!method_oop->has_localvariable_table()) {
734 // Just to check index boundaries
735 jint extra_slot = (_type == T_LONG || _type == T_DOUBLE) ? 1 : 0;
736 if (_index < 0 || _index + extra_slot >= method_oop->max_locals()) {
737 _result = JVMTI_ERROR_INVALID_SLOT;
738 return false;
739 }
740 return true;
741 }
742
743 jint num_entries = method_oop->localvariable_table_length();
744 if (num_entries == 0) {
745 _result = JVMTI_ERROR_INVALID_SLOT;
746 return false; // There are no slots
747 }
748 int signature_idx = -1;
749 int vf_bci = jvf->bci();
750 LocalVariableTableElement* table = method_oop->localvariable_table_start();
751 for (int i = 0; i < num_entries; i++) {
752 int start_bci = table[i].start_bci;
753 int end_bci = start_bci + table[i].length;
754
755 // Here we assume that locations of LVT entries
756 // with the same slot number cannot be overlapped
757 if (_index == (jint) table[i].slot && start_bci <= vf_bci && vf_bci <= end_bci) {
758 signature_idx = (int) table[i].descriptor_cp_index;
759 break;
760 }
761 }
762 if (signature_idx == -1) {
763 _result = JVMTI_ERROR_INVALID_SLOT;
764 return false; // Incorrect slot index
765 }
766 symbolOop sign_sym = method_oop->constants()->symbol_at(signature_idx);
767 const char* signature = (const char *) sign_sym->as_utf8();
768 BasicType slot_type = char2type(signature[0]);
769
770 switch (slot_type) {
771 case T_BYTE:
772 case T_SHORT:
773 case T_CHAR:
774 case T_BOOLEAN:
775 slot_type = T_INT;
776 break;
777 case T_ARRAY:
778 slot_type = T_OBJECT;
779 break;
780 };
781 if (_type != slot_type) {
782 _result = JVMTI_ERROR_TYPE_MISMATCH;
783 return false;
784 }
785
786 jobject jobj = _value.l;
787 if (_set && slot_type == T_OBJECT && jobj != NULL) { // NULL reference is allowed
788 // Check that the jobject class matches the return type signature.
789 JavaThread* cur_thread = JavaThread::current();
790 HandleMark hm(cur_thread);
791
792 Handle obj = Handle(cur_thread, JNIHandles::resolve_external_guard(jobj));
793 NULL_CHECK(obj, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
794 KlassHandle ob_kh = KlassHandle(cur_thread, obj->klass());
795 NULL_CHECK(ob_kh, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
796
797 if (!is_assignable(signature, Klass::cast(ob_kh()), cur_thread)) {
798 _result = JVMTI_ERROR_TYPE_MISMATCH;
799 return false;
800 }
801 }
802 return true;
803 }
804
805 static bool can_be_deoptimized(vframe* vf) {
806 return (vf->is_compiled_frame() && vf->fr().can_be_deoptimized());
807 }
808
809 bool VM_GetOrSetLocal::doit_prologue() {
810 _jvf = get_java_vframe();
811 NULL_CHECK(_jvf, false);
812
813 if (!check_slot_type(_jvf)) {
814 return false;
815 }
816 return true;
817 }
818
819 void VM_GetOrSetLocal::doit() {
820 if (_set) {
821 // Force deoptimization of frame if compiled because it's
822 // possible the compiler emitted some locals as constant values,
823 // meaning they are not mutable.
824 if (can_be_deoptimized(_jvf)) {
825
826 // Schedule deoptimization so that eventually the local
827 // update will be written to an interpreter frame.
828 VM_DeoptimizeFrame deopt(_jvf->thread(), _jvf->fr().id());
829 VMThread::execute(&deopt);
830
831 // Now store a new value for the local which will be applied
832 // once deoptimization occurs. Note however that while this
833 // write is deferred until deoptimization actually happens
834 // can vframe created after this point will have its locals
835 // reflecting this update so as far as anyone can see the
836 // write has already taken place.
837
838 // If we are updating an oop then get the oop from the handle
839 // since the handle will be long gone by the time the deopt
840 // happens. The oop stored in the deferred local will be
841 // gc'd on its own.
842 if (_type == T_OBJECT) {
843 _value.l = (jobject) (JNIHandles::resolve_external_guard(_value.l));
844 }
845 // Re-read the vframe so we can see that it is deoptimized
846 // [ Only need because of assert in update_local() ]
847 _jvf = get_java_vframe();
848 ((compiledVFrame*)_jvf)->update_local(_type, _index, _value);
849 return;
850 }
851 StackValueCollection *locals = _jvf->locals();
852 HandleMark hm;
853
854 switch (_type) {
855 case T_INT: locals->set_int_at (_index, _value.i); break;
856 case T_LONG: locals->set_long_at (_index, _value.j); break;
857 case T_FLOAT: locals->set_float_at (_index, _value.f); break;
858 case T_DOUBLE: locals->set_double_at(_index, _value.d); break;
859 case T_OBJECT: {
860 Handle ob_h(JNIHandles::resolve_external_guard(_value.l));
861 locals->set_obj_at (_index, ob_h);
862 break;
863 }
864 default: ShouldNotReachHere();
865 }
866 _jvf->set_locals(locals);
867 } else {
868 StackValueCollection *locals = _jvf->locals();
869
870 if (locals->at(_index)->type() == T_CONFLICT) {
871 memset(&_value, 0, sizeof(_value));
872 _value.l = NULL;
873 return;
874 }
875
876 switch (_type) {
877 case T_INT: _value.i = locals->int_at (_index); break;
878 case T_LONG: _value.j = locals->long_at (_index); break;
879 case T_FLOAT: _value.f = locals->float_at (_index); break;
880 case T_DOUBLE: _value.d = locals->double_at(_index); break;
881 case T_OBJECT: {
882 // Wrap the oop to be returned in a local JNI handle since
883 // oops_do() no longer applies after doit() is finished.
884 oop obj = locals->obj_at(_index)();
885 _value.l = JNIHandles::make_local(_calling_thread, obj);
886 break;
887 }
888 default: ShouldNotReachHere();
889 }
890 }
891 }
892
893
894 bool VM_GetOrSetLocal::allow_nested_vm_operations() const {
895 return true; // May need to deoptimize
896 }
897
898
899 /////////////////////////////////////////////////////////////////////////////////////////
900
901 //
902 // class JvmtiSuspendControl - see comments in jvmtiImpl.hpp
903 //
904
905 bool JvmtiSuspendControl::suspend(JavaThread *java_thread) {
906 // external suspend should have caught suspending a thread twice
907
908 // Immediate suspension required for JPDA back-end so JVMTI agent threads do
909 // not deadlock due to later suspension on transitions while holding
910 // raw monitors. Passing true causes the immediate suspension.
911 // java_suspend() will catch threads in the process of exiting
912 // and will ignore them.
913 java_thread->java_suspend();
914
915 // It would be nice to have the following assertion in all the time,
916 // but it is possible for a racing resume request to have resumed
917 // this thread right after we suspended it. Temporarily enable this
918 // assertion if you are chasing a different kind of bug.
919 //
920 // assert(java_lang_Thread::thread(java_thread->threadObj()) == NULL ||
921 // java_thread->is_being_ext_suspended(), "thread is not suspended");
922
923 if (java_lang_Thread::thread(java_thread->threadObj()) == NULL) {
924 // check again because we can get delayed in java_suspend():
925 // the thread is in process of exiting.
926 return false;
927 }
928
929 return true;
930 }
931
932 bool JvmtiSuspendControl::resume(JavaThread *java_thread) {
933 // external suspend should have caught resuming a thread twice
934 assert(java_thread->is_being_ext_suspended(), "thread should be suspended");
935
936 // resume thread
937 {
938 // must always grab Threads_lock, see JVM_SuspendThread
939 MutexLocker ml(Threads_lock);
940 java_thread->java_resume();
941 }
942
943 return true;
944 }
945
946
947 void JvmtiSuspendControl::print() {
948 #ifndef PRODUCT
949 MutexLocker mu(Threads_lock);
950 ResourceMark rm;
951
952 tty->print("Suspended Threads: [");
953 for (JavaThread *thread = Threads::first(); thread != NULL; thread = thread->next()) {
954 #if JVMTI_TRACE
955 const char *name = JvmtiTrace::safe_get_thread_name(thread);
956 #else
957 const char *name = "";
958 #endif /*JVMTI_TRACE */
959 tty->print("%s(%c ", name, thread->is_being_ext_suspended() ? 'S' : '_');
960 if (!thread->has_last_Java_frame()) {
961 tty->print("no stack");
962 }
963 tty->print(") ");
964 }
965 tty->print_cr("]");
966 #endif
967 }