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 "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/atomic.hpp"
36 #include "runtime/deoptimization.hpp"
37 #include "runtime/handles.hpp"
38 #include "runtime/handles.inline.hpp"
39 #include "runtime/interfaceSupport.hpp"
40 #include "runtime/javaCalls.hpp"
41 #include "runtime/os.hpp"
42 #include "runtime/serviceThread.hpp"
43 #include "runtime/signature.hpp"
44 #include "runtime/thread.inline.hpp"
45 #include "runtime/vframe.hpp"
46 #include "runtime/vframe_hp.hpp"
47 #include "runtime/vm_operations.hpp"
48 #include "utilities/exceptions.hpp"
50 //
51 // class JvmtiAgentThread
52 //
53 // JavaThread used to wrap a thread started by an agent
54 // using the JVMTI method RunAgentThread.
55 //
57 JvmtiAgentThread::JvmtiAgentThread(JvmtiEnv* env, jvmtiStartFunction start_fn, const void *start_arg)
58 : JavaThread(start_function_wrapper) {
59 _env = env;
60 _start_fn = start_fn;
61 _start_arg = start_arg;
62 }
64 void
65 JvmtiAgentThread::start_function_wrapper(JavaThread *thread, TRAPS) {
66 // It is expected that any Agent threads will be created as
67 // Java Threads. If this is the case, notification of the creation
68 // of the thread is given in JavaThread::thread_main().
69 assert(thread->is_Java_thread(), "debugger thread should be a Java Thread");
70 assert(thread == JavaThread::current(), "sanity check");
72 JvmtiAgentThread *dthread = (JvmtiAgentThread *)thread;
73 dthread->call_start_function();
74 }
76 void
77 JvmtiAgentThread::call_start_function() {
78 ThreadToNativeFromVM transition(this);
79 _start_fn(_env->jvmti_external(), jni_environment(), (void*)_start_arg);
80 }
83 //
84 // class GrowableCache - private methods
85 //
87 void GrowableCache::recache() {
88 int len = _elements->length();
90 FREE_C_HEAP_ARRAY(address, _cache, mtInternal);
91 _cache = NEW_C_HEAP_ARRAY(address,len+1, mtInternal);
93 for (int i=0; i<len; i++) {
94 _cache[i] = _elements->at(i)->getCacheValue();
95 //
96 // The cache entry has gone bad. Without a valid frame pointer
97 // value, the entry is useless so we simply delete it in product
98 // mode. The call to remove() will rebuild the cache again
99 // without the bad entry.
100 //
101 if (_cache[i] == NULL) {
102 assert(false, "cannot recache NULL elements");
103 remove(i);
104 return;
105 }
106 }
107 _cache[len] = NULL;
109 _listener_fun(_this_obj,_cache);
110 }
112 bool GrowableCache::equals(void* v, GrowableElement *e2) {
113 GrowableElement *e1 = (GrowableElement *) v;
114 assert(e1 != NULL, "e1 != NULL");
115 assert(e2 != NULL, "e2 != NULL");
117 return e1->equals(e2);
118 }
120 //
121 // class GrowableCache - public methods
122 //
124 GrowableCache::GrowableCache() {
125 _this_obj = NULL;
126 _listener_fun = NULL;
127 _elements = NULL;
128 _cache = NULL;
129 }
131 GrowableCache::~GrowableCache() {
132 clear();
133 delete _elements;
134 FREE_C_HEAP_ARRAY(address, _cache, mtInternal);
135 }
137 void GrowableCache::initialize(void *this_obj, void listener_fun(void *, address*) ) {
138 _this_obj = this_obj;
139 _listener_fun = listener_fun;
140 _elements = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<GrowableElement*>(5,true);
141 recache();
142 }
144 // number of elements in the collection
145 int GrowableCache::length() {
146 return _elements->length();
147 }
149 // get the value of the index element in the collection
150 GrowableElement* GrowableCache::at(int index) {
151 GrowableElement *e = (GrowableElement *) _elements->at(index);
152 assert(e != NULL, "e != NULL");
153 return e;
154 }
156 int GrowableCache::find(GrowableElement* e) {
157 return _elements->find(e, GrowableCache::equals);
158 }
160 // append a copy of the element to the end of the collection
161 void GrowableCache::append(GrowableElement* e) {
162 GrowableElement *new_e = e->clone();
163 _elements->append(new_e);
164 recache();
165 }
167 // insert a copy of the element using lessthan()
168 void GrowableCache::insert(GrowableElement* e) {
169 GrowableElement *new_e = e->clone();
170 _elements->append(new_e);
172 int n = length()-2;
173 for (int i=n; i>=0; i--) {
174 GrowableElement *e1 = _elements->at(i);
175 GrowableElement *e2 = _elements->at(i+1);
176 if (e2->lessThan(e1)) {
177 _elements->at_put(i+1, e1);
178 _elements->at_put(i, e2);
179 }
180 }
182 recache();
183 }
185 // remove the element at index
186 void GrowableCache::remove (int index) {
187 GrowableElement *e = _elements->at(index);
188 assert(e != NULL, "e != NULL");
189 _elements->remove(e);
190 delete e;
191 recache();
192 }
194 // clear out all elements, release all heap space and
195 // let our listener know that things have changed.
196 void GrowableCache::clear() {
197 int len = _elements->length();
198 for (int i=0; i<len; i++) {
199 delete _elements->at(i);
200 }
201 _elements->clear();
202 recache();
203 }
205 void GrowableCache::oops_do(OopClosure* f) {
206 int len = _elements->length();
207 for (int i=0; i<len; i++) {
208 GrowableElement *e = _elements->at(i);
209 e->oops_do(f);
210 }
211 }
213 void GrowableCache::gc_epilogue() {
214 int len = _elements->length();
215 for (int i=0; i<len; i++) {
216 _cache[i] = _elements->at(i)->getCacheValue();
217 }
218 }
220 //
221 // class JvmtiBreakpoint
222 //
224 JvmtiBreakpoint::JvmtiBreakpoint() {
225 _method = NULL;
226 _bci = 0;
227 _class_loader = NULL;
228 #ifdef CHECK_UNHANDLED_OOPS
229 // This one is always allocated with new, but check it just in case.
230 Thread *thread = Thread::current();
231 if (thread->is_in_stack((address)&_method)) {
232 thread->allow_unhandled_oop((oop*)&_method);
233 }
234 #endif // CHECK_UNHANDLED_OOPS
235 }
237 JvmtiBreakpoint::JvmtiBreakpoint(Method* m_method, jlocation location) {
238 _method = m_method;
239 _class_loader = _method->method_holder()->class_loader_data()->class_loader();
240 assert(_method != NULL, "_method != NULL");
241 _bci = (int) location;
242 assert(_bci >= 0, "_bci >= 0");
243 }
245 void JvmtiBreakpoint::copy(JvmtiBreakpoint& bp) {
246 _method = bp._method;
247 _bci = bp._bci;
248 _class_loader = bp._class_loader;
249 }
251 bool JvmtiBreakpoint::lessThan(JvmtiBreakpoint& bp) {
252 Unimplemented();
253 return false;
254 }
256 bool JvmtiBreakpoint::equals(JvmtiBreakpoint& bp) {
257 return _method == bp._method
258 && _bci == bp._bci;
259 }
261 bool JvmtiBreakpoint::is_valid() {
262 // class loader can be NULL
263 return _method != NULL &&
264 _bci >= 0;
265 }
267 address JvmtiBreakpoint::getBcp() {
268 return _method->bcp_from(_bci);
269 }
271 void JvmtiBreakpoint::each_method_version_do(method_action meth_act) {
272 ((Method*)_method->*meth_act)(_bci);
274 // add/remove breakpoint to/from versions of the method that
275 // are EMCP. Directly or transitively obsolete methods are
276 // not saved in the PreviousVersionInfo.
277 Thread *thread = Thread::current();
278 instanceKlassHandle ikh = instanceKlassHandle(thread, _method->method_holder());
279 Symbol* m_name = _method->name();
280 Symbol* m_signature = _method->signature();
282 {
283 ResourceMark rm(thread);
284 // PreviousVersionInfo objects returned via PreviousVersionWalker
285 // contain a GrowableArray of handles. We have to clean up the
286 // GrowableArray _after_ the PreviousVersionWalker destructor
287 // has destroyed the handles.
288 {
289 // search previous versions if they exist
290 PreviousVersionWalker pvw((InstanceKlass *)ikh());
291 for (PreviousVersionInfo * pv_info = pvw.next_previous_version();
292 pv_info != NULL; pv_info = pvw.next_previous_version()) {
293 GrowableArray<methodHandle>* methods =
294 pv_info->prev_EMCP_method_handles();
296 if (methods == NULL) {
297 // We have run into a PreviousVersion generation where
298 // all methods were made obsolete during that generation's
299 // RedefineClasses() operation. At the time of that
300 // operation, all EMCP methods were flushed so we don't
301 // have to go back any further.
302 //
303 // A NULL methods array is different than an empty methods
304 // array. We cannot infer any optimizations about older
305 // generations from an empty methods array for the current
306 // generation.
307 break;
308 }
310 for (int i = methods->length() - 1; i >= 0; i--) {
311 methodHandle method = methods->at(i);
312 // obsolete methods that are running are not deleted from
313 // previous version array, but they are skipped here.
314 if (!method->is_obsolete() &&
315 method->name() == m_name &&
316 method->signature() == m_signature) {
317 RC_TRACE(0x00000800, ("%sing breakpoint in %s(%s)",
318 meth_act == &Method::set_breakpoint ? "sett" : "clear",
319 method->name()->as_C_string(),
320 method->signature()->as_C_string()));
322 ((Method*)method()->*meth_act)(_bci);
323 break;
324 }
325 }
326 }
327 } // pvw is cleaned up
328 } // rm is cleaned up
329 }
331 void JvmtiBreakpoint::set() {
332 each_method_version_do(&Method::set_breakpoint);
333 }
335 void JvmtiBreakpoint::clear() {
336 each_method_version_do(&Method::clear_breakpoint);
337 }
339 void JvmtiBreakpoint::print() {
340 #ifndef PRODUCT
341 const char *class_name = (_method == NULL) ? "NULL" : _method->klass_name()->as_C_string();
342 const char *method_name = (_method == NULL) ? "NULL" : _method->name()->as_C_string();
344 tty->print("Breakpoint(%s,%s,%d,%p)",class_name, method_name, _bci, getBcp());
345 #endif
346 }
349 //
350 // class VM_ChangeBreakpoints
351 //
352 // Modify the Breakpoints data structure at a safepoint
353 //
355 void VM_ChangeBreakpoints::doit() {
356 switch (_operation) {
357 case SET_BREAKPOINT:
358 _breakpoints->set_at_safepoint(*_bp);
359 break;
360 case CLEAR_BREAKPOINT:
361 _breakpoints->clear_at_safepoint(*_bp);
362 break;
363 default:
364 assert(false, "Unknown operation");
365 }
366 }
368 void VM_ChangeBreakpoints::oops_do(OopClosure* f) {
369 // The JvmtiBreakpoints in _breakpoints will be visited via
370 // JvmtiExport::oops_do.
371 if (_bp != NULL) {
372 _bp->oops_do(f);
373 }
374 }
376 //
377 // class JvmtiBreakpoints
378 //
379 // a JVMTI internal collection of JvmtiBreakpoint
380 //
382 JvmtiBreakpoints::JvmtiBreakpoints(void listener_fun(void *,address *)) {
383 _bps.initialize(this,listener_fun);
384 }
386 JvmtiBreakpoints:: ~JvmtiBreakpoints() {}
388 void JvmtiBreakpoints::oops_do(OopClosure* f) {
389 _bps.oops_do(f);
390 }
392 void JvmtiBreakpoints::gc_epilogue() {
393 _bps.gc_epilogue();
394 }
396 void JvmtiBreakpoints::print() {
397 #ifndef PRODUCT
398 ResourceMark rm;
400 int n = _bps.length();
401 for (int i=0; i<n; i++) {
402 JvmtiBreakpoint& bp = _bps.at(i);
403 tty->print("%d: ", i);
404 bp.print();
405 tty->print_cr("");
406 }
407 #endif
408 }
411 void JvmtiBreakpoints::set_at_safepoint(JvmtiBreakpoint& bp) {
412 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
414 int i = _bps.find(bp);
415 if (i == -1) {
416 _bps.append(bp);
417 bp.set();
418 }
419 }
421 void JvmtiBreakpoints::clear_at_safepoint(JvmtiBreakpoint& bp) {
422 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
424 int i = _bps.find(bp);
425 if (i != -1) {
426 _bps.remove(i);
427 bp.clear();
428 }
429 }
431 int JvmtiBreakpoints::length() { return _bps.length(); }
433 int JvmtiBreakpoints::set(JvmtiBreakpoint& bp) {
434 if ( _bps.find(bp) != -1) {
435 return JVMTI_ERROR_DUPLICATE;
436 }
437 VM_ChangeBreakpoints set_breakpoint(VM_ChangeBreakpoints::SET_BREAKPOINT, &bp);
438 VMThread::execute(&set_breakpoint);
439 return JVMTI_ERROR_NONE;
440 }
442 int JvmtiBreakpoints::clear(JvmtiBreakpoint& bp) {
443 if ( _bps.find(bp) == -1) {
444 return JVMTI_ERROR_NOT_FOUND;
445 }
447 VM_ChangeBreakpoints clear_breakpoint(VM_ChangeBreakpoints::CLEAR_BREAKPOINT, &bp);
448 VMThread::execute(&clear_breakpoint);
449 return JVMTI_ERROR_NONE;
450 }
452 void JvmtiBreakpoints::clearall_in_class_at_safepoint(Klass* klass) {
453 bool changed = true;
454 // We are going to run thru the list of bkpts
455 // and delete some. This deletion probably alters
456 // the list in some implementation defined way such
457 // that when we delete entry i, the next entry might
458 // no longer be at i+1. To be safe, each time we delete
459 // an entry, we'll just start again from the beginning.
460 // We'll stop when we make a pass thru the whole list without
461 // deleting anything.
462 while (changed) {
463 int len = _bps.length();
464 changed = false;
465 for (int i = 0; i < len; i++) {
466 JvmtiBreakpoint& bp = _bps.at(i);
467 if (bp.method()->method_holder() == klass) {
468 bp.clear();
469 _bps.remove(i);
470 // This changed 'i' so we have to start over.
471 changed = true;
472 break;
473 }
474 }
475 }
476 }
478 //
479 // class JvmtiCurrentBreakpoints
480 //
482 JvmtiBreakpoints *JvmtiCurrentBreakpoints::_jvmti_breakpoints = NULL;
483 address * JvmtiCurrentBreakpoints::_breakpoint_list = NULL;
486 JvmtiBreakpoints& JvmtiCurrentBreakpoints::get_jvmti_breakpoints() {
487 if (_jvmti_breakpoints != NULL) return (*_jvmti_breakpoints);
488 _jvmti_breakpoints = new JvmtiBreakpoints(listener_fun);
489 assert(_jvmti_breakpoints != NULL, "_jvmti_breakpoints != NULL");
490 return (*_jvmti_breakpoints);
491 }
493 void JvmtiCurrentBreakpoints::listener_fun(void *this_obj, address *cache) {
494 JvmtiBreakpoints *this_jvmti = (JvmtiBreakpoints *) this_obj;
495 assert(this_jvmti != NULL, "this_jvmti != NULL");
497 debug_only(int n = this_jvmti->length(););
498 assert(cache[n] == NULL, "cache must be NULL terminated");
500 set_breakpoint_list(cache);
501 }
504 void JvmtiCurrentBreakpoints::oops_do(OopClosure* f) {
505 if (_jvmti_breakpoints != NULL) {
506 _jvmti_breakpoints->oops_do(f);
507 }
508 }
510 void JvmtiCurrentBreakpoints::gc_epilogue() {
511 if (_jvmti_breakpoints != NULL) {
512 _jvmti_breakpoints->gc_epilogue();
513 }
514 }
516 ///////////////////////////////////////////////////////////////
517 //
518 // class VM_GetOrSetLocal
519 //
521 // Constructor for non-object getter
522 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, int index, BasicType type)
523 : _thread(thread)
524 , _calling_thread(NULL)
525 , _depth(depth)
526 , _index(index)
527 , _type(type)
528 , _set(false)
529 , _jvf(NULL)
530 , _result(JVMTI_ERROR_NONE)
531 {
532 }
534 // Constructor for object or non-object setter
535 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, int index, BasicType type, jvalue value)
536 : _thread(thread)
537 , _calling_thread(NULL)
538 , _depth(depth)
539 , _index(index)
540 , _type(type)
541 , _value(value)
542 , _set(true)
543 , _jvf(NULL)
544 , _result(JVMTI_ERROR_NONE)
545 {
546 }
548 // Constructor for object getter
549 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, JavaThread* calling_thread, jint depth, int index)
550 : _thread(thread)
551 , _calling_thread(calling_thread)
552 , _depth(depth)
553 , _index(index)
554 , _type(T_OBJECT)
555 , _set(false)
556 , _jvf(NULL)
557 , _result(JVMTI_ERROR_NONE)
558 {
559 }
561 vframe *VM_GetOrSetLocal::get_vframe() {
562 if (!_thread->has_last_Java_frame()) {
563 return NULL;
564 }
565 RegisterMap reg_map(_thread);
566 vframe *vf = _thread->last_java_vframe(®_map);
567 int d = 0;
568 while ((vf != NULL) && (d < _depth)) {
569 vf = vf->java_sender();
570 d++;
571 }
572 return vf;
573 }
575 javaVFrame *VM_GetOrSetLocal::get_java_vframe() {
576 vframe* vf = get_vframe();
577 if (vf == NULL) {
578 _result = JVMTI_ERROR_NO_MORE_FRAMES;
579 return NULL;
580 }
581 javaVFrame *jvf = (javaVFrame*)vf;
583 if (!vf->is_java_frame()) {
584 _result = JVMTI_ERROR_OPAQUE_FRAME;
585 return NULL;
586 }
587 return jvf;
588 }
590 // Check that the klass is assignable to a type with the given signature.
591 // Another solution could be to use the function Klass::is_subtype_of(type).
592 // But the type class can be forced to load/initialize eagerly in such a case.
593 // This may cause unexpected consequences like CFLH or class-init JVMTI events.
594 // It is better to avoid such a behavior.
595 bool VM_GetOrSetLocal::is_assignable(const char* ty_sign, Klass* klass, Thread* thread) {
596 assert(ty_sign != NULL, "type signature must not be NULL");
597 assert(thread != NULL, "thread must not be NULL");
598 assert(klass != NULL, "klass must not be NULL");
600 int len = (int) strlen(ty_sign);
601 if (ty_sign[0] == 'L' && ty_sign[len-1] == ';') { // Need pure class/interface name
602 ty_sign++;
603 len -= 2;
604 }
605 TempNewSymbol ty_sym = SymbolTable::new_symbol(ty_sign, len, thread);
606 if (klass->name() == ty_sym) {
607 return true;
608 }
609 // Compare primary supers
610 int super_depth = klass->super_depth();
611 int idx;
612 for (idx = 0; idx < super_depth; idx++) {
613 if (klass->primary_super_of_depth(idx)->name() == ty_sym) {
614 return true;
615 }
616 }
617 // Compare secondary supers
618 Array<Klass*>* sec_supers = klass->secondary_supers();
619 for (idx = 0; idx < sec_supers->length(); idx++) {
620 if (((Klass*) sec_supers->at(idx))->name() == ty_sym) {
621 return true;
622 }
623 }
624 return false;
625 }
627 // Checks error conditions:
628 // JVMTI_ERROR_INVALID_SLOT
629 // JVMTI_ERROR_TYPE_MISMATCH
630 // Returns: 'true' - everything is Ok, 'false' - error code
632 bool VM_GetOrSetLocal::check_slot_type(javaVFrame* jvf) {
633 Method* method_oop = jvf->method();
634 if (!method_oop->has_localvariable_table()) {
635 // Just to check index boundaries
636 jint extra_slot = (_type == T_LONG || _type == T_DOUBLE) ? 1 : 0;
637 if (_index < 0 || _index + extra_slot >= method_oop->max_locals()) {
638 _result = JVMTI_ERROR_INVALID_SLOT;
639 return false;
640 }
641 return true;
642 }
644 jint num_entries = method_oop->localvariable_table_length();
645 if (num_entries == 0) {
646 _result = JVMTI_ERROR_INVALID_SLOT;
647 return false; // There are no slots
648 }
649 int signature_idx = -1;
650 int vf_bci = jvf->bci();
651 LocalVariableTableElement* table = method_oop->localvariable_table_start();
652 for (int i = 0; i < num_entries; i++) {
653 int start_bci = table[i].start_bci;
654 int end_bci = start_bci + table[i].length;
656 // Here we assume that locations of LVT entries
657 // with the same slot number cannot be overlapped
658 if (_index == (jint) table[i].slot && start_bci <= vf_bci && vf_bci <= end_bci) {
659 signature_idx = (int) table[i].descriptor_cp_index;
660 break;
661 }
662 }
663 if (signature_idx == -1) {
664 _result = JVMTI_ERROR_INVALID_SLOT;
665 return false; // Incorrect slot index
666 }
667 Symbol* sign_sym = method_oop->constants()->symbol_at(signature_idx);
668 const char* signature = (const char *) sign_sym->as_utf8();
669 BasicType slot_type = char2type(signature[0]);
671 switch (slot_type) {
672 case T_BYTE:
673 case T_SHORT:
674 case T_CHAR:
675 case T_BOOLEAN:
676 slot_type = T_INT;
677 break;
678 case T_ARRAY:
679 slot_type = T_OBJECT;
680 break;
681 };
682 if (_type != slot_type) {
683 _result = JVMTI_ERROR_TYPE_MISMATCH;
684 return false;
685 }
687 jobject jobj = _value.l;
688 if (_set && slot_type == T_OBJECT && jobj != NULL) { // NULL reference is allowed
689 // Check that the jobject class matches the return type signature.
690 JavaThread* cur_thread = JavaThread::current();
691 HandleMark hm(cur_thread);
693 Handle obj = Handle(cur_thread, JNIHandles::resolve_external_guard(jobj));
694 NULL_CHECK(obj, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
695 KlassHandle ob_kh = KlassHandle(cur_thread, obj->klass());
696 NULL_CHECK(ob_kh, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
698 if (!is_assignable(signature, ob_kh(), cur_thread)) {
699 _result = JVMTI_ERROR_TYPE_MISMATCH;
700 return false;
701 }
702 }
703 return true;
704 }
706 static bool can_be_deoptimized(vframe* vf) {
707 return (vf->is_compiled_frame() && vf->fr().can_be_deoptimized());
708 }
710 bool VM_GetOrSetLocal::doit_prologue() {
711 _jvf = get_java_vframe();
712 NULL_CHECK(_jvf, false);
714 if (_jvf->method()->is_native()) {
715 if (getting_receiver() && !_jvf->method()->is_static()) {
716 return true;
717 } else {
718 _result = JVMTI_ERROR_OPAQUE_FRAME;
719 return false;
720 }
721 }
723 if (!check_slot_type(_jvf)) {
724 return false;
725 }
726 return true;
727 }
729 void VM_GetOrSetLocal::doit() {
730 if (_set) {
731 // Force deoptimization of frame if compiled because it's
732 // possible the compiler emitted some locals as constant values,
733 // meaning they are not mutable.
734 if (can_be_deoptimized(_jvf)) {
736 // Schedule deoptimization so that eventually the local
737 // update will be written to an interpreter frame.
738 Deoptimization::deoptimize_frame(_jvf->thread(), _jvf->fr().id());
740 // Now store a new value for the local which will be applied
741 // once deoptimization occurs. Note however that while this
742 // write is deferred until deoptimization actually happens
743 // can vframe created after this point will have its locals
744 // reflecting this update so as far as anyone can see the
745 // write has already taken place.
747 // If we are updating an oop then get the oop from the handle
748 // since the handle will be long gone by the time the deopt
749 // happens. The oop stored in the deferred local will be
750 // gc'd on its own.
751 if (_type == T_OBJECT) {
752 _value.l = (jobject) (JNIHandles::resolve_external_guard(_value.l));
753 }
754 // Re-read the vframe so we can see that it is deoptimized
755 // [ Only need because of assert in update_local() ]
756 _jvf = get_java_vframe();
757 ((compiledVFrame*)_jvf)->update_local(_type, _index, _value);
758 return;
759 }
760 StackValueCollection *locals = _jvf->locals();
761 HandleMark hm;
763 switch (_type) {
764 case T_INT: locals->set_int_at (_index, _value.i); break;
765 case T_LONG: locals->set_long_at (_index, _value.j); break;
766 case T_FLOAT: locals->set_float_at (_index, _value.f); break;
767 case T_DOUBLE: locals->set_double_at(_index, _value.d); break;
768 case T_OBJECT: {
769 Handle ob_h(JNIHandles::resolve_external_guard(_value.l));
770 locals->set_obj_at (_index, ob_h);
771 break;
772 }
773 default: ShouldNotReachHere();
774 }
775 _jvf->set_locals(locals);
776 } else {
777 if (_jvf->method()->is_native() && _jvf->is_compiled_frame()) {
778 assert(getting_receiver(), "Can only get here when getting receiver");
779 oop receiver = _jvf->fr().get_native_receiver();
780 _value.l = JNIHandles::make_local(_calling_thread, receiver);
781 } else {
782 StackValueCollection *locals = _jvf->locals();
784 if (locals->at(_index)->type() == T_CONFLICT) {
785 memset(&_value, 0, sizeof(_value));
786 _value.l = NULL;
787 return;
788 }
790 switch (_type) {
791 case T_INT: _value.i = locals->int_at (_index); break;
792 case T_LONG: _value.j = locals->long_at (_index); break;
793 case T_FLOAT: _value.f = locals->float_at (_index); break;
794 case T_DOUBLE: _value.d = locals->double_at(_index); break;
795 case T_OBJECT: {
796 // Wrap the oop to be returned in a local JNI handle since
797 // oops_do() no longer applies after doit() is finished.
798 oop obj = locals->obj_at(_index)();
799 _value.l = JNIHandles::make_local(_calling_thread, obj);
800 break;
801 }
802 default: ShouldNotReachHere();
803 }
804 }
805 }
806 }
809 bool VM_GetOrSetLocal::allow_nested_vm_operations() const {
810 return true; // May need to deoptimize
811 }
814 VM_GetReceiver::VM_GetReceiver(
815 JavaThread* thread, JavaThread* caller_thread, jint depth)
816 : VM_GetOrSetLocal(thread, caller_thread, depth, 0) {}
818 /////////////////////////////////////////////////////////////////////////////////////////
820 //
821 // class JvmtiSuspendControl - see comments in jvmtiImpl.hpp
822 //
824 bool JvmtiSuspendControl::suspend(JavaThread *java_thread) {
825 // external suspend should have caught suspending a thread twice
827 // Immediate suspension required for JPDA back-end so JVMTI agent threads do
828 // not deadlock due to later suspension on transitions while holding
829 // raw monitors. Passing true causes the immediate suspension.
830 // java_suspend() will catch threads in the process of exiting
831 // and will ignore them.
832 java_thread->java_suspend();
834 // It would be nice to have the following assertion in all the time,
835 // but it is possible for a racing resume request to have resumed
836 // this thread right after we suspended it. Temporarily enable this
837 // assertion if you are chasing a different kind of bug.
838 //
839 // assert(java_lang_Thread::thread(java_thread->threadObj()) == NULL ||
840 // java_thread->is_being_ext_suspended(), "thread is not suspended");
842 if (java_lang_Thread::thread(java_thread->threadObj()) == NULL) {
843 // check again because we can get delayed in java_suspend():
844 // the thread is in process of exiting.
845 return false;
846 }
848 return true;
849 }
851 bool JvmtiSuspendControl::resume(JavaThread *java_thread) {
852 // external suspend should have caught resuming a thread twice
853 assert(java_thread->is_being_ext_suspended(), "thread should be suspended");
855 // resume thread
856 {
857 // must always grab Threads_lock, see JVM_SuspendThread
858 MutexLocker ml(Threads_lock);
859 java_thread->java_resume();
860 }
862 return true;
863 }
866 void JvmtiSuspendControl::print() {
867 #ifndef PRODUCT
868 MutexLocker mu(Threads_lock);
869 ResourceMark rm;
871 tty->print("Suspended Threads: [");
872 for (JavaThread *thread = Threads::first(); thread != NULL; thread = thread->next()) {
873 #ifdef JVMTI_TRACE
874 const char *name = JvmtiTrace::safe_get_thread_name(thread);
875 #else
876 const char *name = "";
877 #endif /*JVMTI_TRACE */
878 tty->print("%s(%c ", name, thread->is_being_ext_suspended() ? 'S' : '_');
879 if (!thread->has_last_Java_frame()) {
880 tty->print("no stack");
881 }
882 tty->print(") ");
883 }
884 tty->print_cr("]");
885 #endif
886 }
888 JvmtiDeferredEvent JvmtiDeferredEvent::compiled_method_load_event(
889 nmethod* nm) {
890 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_COMPILED_METHOD_LOAD);
891 event._event_data.compiled_method_load = nm;
892 // Keep the nmethod alive until the ServiceThread can process
893 // this deferred event.
894 nmethodLocker::lock_nmethod(nm);
895 return event;
896 }
898 JvmtiDeferredEvent JvmtiDeferredEvent::compiled_method_unload_event(
899 nmethod* nm, jmethodID id, const void* code) {
900 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_COMPILED_METHOD_UNLOAD);
901 event._event_data.compiled_method_unload.nm = nm;
902 event._event_data.compiled_method_unload.method_id = id;
903 event._event_data.compiled_method_unload.code_begin = code;
904 // Keep the nmethod alive until the ServiceThread can process
905 // this deferred event. This will keep the memory for the
906 // generated code from being reused too early. We pass
907 // zombie_ok == true here so that our nmethod that was just
908 // made into a zombie can be locked.
909 nmethodLocker::lock_nmethod(nm, true /* zombie_ok */);
910 return event;
911 }
913 JvmtiDeferredEvent JvmtiDeferredEvent::dynamic_code_generated_event(
914 const char* name, const void* code_begin, const void* code_end) {
915 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_DYNAMIC_CODE_GENERATED);
916 // Need to make a copy of the name since we don't know how long
917 // the event poster will keep it around after we enqueue the
918 // deferred event and return. strdup() failure is handled in
919 // the post() routine below.
920 event._event_data.dynamic_code_generated.name = os::strdup(name);
921 event._event_data.dynamic_code_generated.code_begin = code_begin;
922 event._event_data.dynamic_code_generated.code_end = code_end;
923 return event;
924 }
926 void JvmtiDeferredEvent::post() {
927 assert(ServiceThread::is_service_thread(Thread::current()),
928 "Service thread must post enqueued events");
929 switch(_type) {
930 case TYPE_COMPILED_METHOD_LOAD: {
931 nmethod* nm = _event_data.compiled_method_load;
932 JvmtiExport::post_compiled_method_load(nm);
933 // done with the deferred event so unlock the nmethod
934 nmethodLocker::unlock_nmethod(nm);
935 break;
936 }
937 case TYPE_COMPILED_METHOD_UNLOAD: {
938 nmethod* nm = _event_data.compiled_method_unload.nm;
939 JvmtiExport::post_compiled_method_unload(
940 _event_data.compiled_method_unload.method_id,
941 _event_data.compiled_method_unload.code_begin);
942 // done with the deferred event so unlock the nmethod
943 nmethodLocker::unlock_nmethod(nm);
944 break;
945 }
946 case TYPE_DYNAMIC_CODE_GENERATED: {
947 JvmtiExport::post_dynamic_code_generated_internal(
948 // if strdup failed give the event a default name
949 (_event_data.dynamic_code_generated.name == NULL)
950 ? "unknown_code" : _event_data.dynamic_code_generated.name,
951 _event_data.dynamic_code_generated.code_begin,
952 _event_data.dynamic_code_generated.code_end);
953 if (_event_data.dynamic_code_generated.name != NULL) {
954 // release our copy
955 os::free((void *)_event_data.dynamic_code_generated.name);
956 }
957 break;
958 }
959 default:
960 ShouldNotReachHere();
961 }
962 }
964 JvmtiDeferredEventQueue::QueueNode* JvmtiDeferredEventQueue::_queue_tail = NULL;
965 JvmtiDeferredEventQueue::QueueNode* JvmtiDeferredEventQueue::_queue_head = NULL;
967 volatile JvmtiDeferredEventQueue::QueueNode*
968 JvmtiDeferredEventQueue::_pending_list = NULL;
970 bool JvmtiDeferredEventQueue::has_events() {
971 assert(Service_lock->owned_by_self(), "Must own Service_lock");
972 return _queue_head != NULL || _pending_list != NULL;
973 }
975 void JvmtiDeferredEventQueue::enqueue(const JvmtiDeferredEvent& event) {
976 assert(Service_lock->owned_by_self(), "Must own Service_lock");
978 process_pending_events();
980 // Events get added to the end of the queue (and are pulled off the front).
981 QueueNode* node = new QueueNode(event);
982 if (_queue_tail == NULL) {
983 _queue_tail = _queue_head = node;
984 } else {
985 assert(_queue_tail->next() == NULL, "Must be the last element in the list");
986 _queue_tail->set_next(node);
987 _queue_tail = node;
988 }
990 Service_lock->notify_all();
991 assert((_queue_head == NULL) == (_queue_tail == NULL),
992 "Inconsistent queue markers");
993 }
995 JvmtiDeferredEvent JvmtiDeferredEventQueue::dequeue() {
996 assert(Service_lock->owned_by_self(), "Must own Service_lock");
998 process_pending_events();
1000 assert(_queue_head != NULL, "Nothing to dequeue");
1002 if (_queue_head == NULL) {
1003 // Just in case this happens in product; it shouldn't but let's not crash
1004 return JvmtiDeferredEvent();
1005 }
1007 QueueNode* node = _queue_head;
1008 _queue_head = _queue_head->next();
1009 if (_queue_head == NULL) {
1010 _queue_tail = NULL;
1011 }
1013 assert((_queue_head == NULL) == (_queue_tail == NULL),
1014 "Inconsistent queue markers");
1016 JvmtiDeferredEvent event = node->event();
1017 delete node;
1018 return event;
1019 }
1021 void JvmtiDeferredEventQueue::add_pending_event(
1022 const JvmtiDeferredEvent& event) {
1024 QueueNode* node = new QueueNode(event);
1026 bool success = false;
1027 QueueNode* prev_value = (QueueNode*)_pending_list;
1028 do {
1029 node->set_next(prev_value);
1030 prev_value = (QueueNode*)Atomic::cmpxchg_ptr(
1031 (void*)node, (volatile void*)&_pending_list, (void*)node->next());
1032 } while (prev_value != node->next());
1033 }
1035 // This method transfers any events that were added by someone NOT holding
1036 // the lock into the mainline queue.
1037 void JvmtiDeferredEventQueue::process_pending_events() {
1038 assert(Service_lock->owned_by_self(), "Must own Service_lock");
1040 if (_pending_list != NULL) {
1041 QueueNode* head =
1042 (QueueNode*)Atomic::xchg_ptr(NULL, (volatile void*)&_pending_list);
1044 assert((_queue_head == NULL) == (_queue_tail == NULL),
1045 "Inconsistent queue markers");
1047 if (head != NULL) {
1048 // Since we've treated the pending list as a stack (with newer
1049 // events at the beginning), we need to join the bottom of the stack
1050 // with the 'tail' of the queue in order to get the events in the
1051 // right order. We do this by reversing the pending list and appending
1052 // it to the queue.
1054 QueueNode* new_tail = head;
1055 QueueNode* new_head = NULL;
1057 // This reverses the list
1058 QueueNode* prev = new_tail;
1059 QueueNode* node = new_tail->next();
1060 new_tail->set_next(NULL);
1061 while (node != NULL) {
1062 QueueNode* next = node->next();
1063 node->set_next(prev);
1064 prev = node;
1065 node = next;
1066 }
1067 new_head = prev;
1069 // Now append the new list to the queue
1070 if (_queue_tail != NULL) {
1071 _queue_tail->set_next(new_head);
1072 } else { // _queue_head == NULL
1073 _queue_head = new_head;
1074 }
1075 _queue_tail = new_tail;
1076 }
1077 }
1078 }