1 /*
2 * Copyright (c) 2003, 2019, 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/symbolTable.hpp"
27 #include "classfile/systemDictionary.hpp"
28 #include "code/nmethod.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "interpreter/oopMapCache.hpp"
31 #include "jvmtifiles/jvmtiEnv.hpp"
32 #include "logging/log.hpp"
33 #include "logging/logStream.hpp"
34 #include "memory/allocation.inline.hpp"
35 #include "memory/resourceArea.hpp"
36 #include "oops/instanceKlass.hpp"
37 #include "oops/oop.inline.hpp"
38 #include "prims/jvmtiAgentThread.hpp"
39 #include "prims/jvmtiEventController.inline.hpp"
40 #include "prims/jvmtiImpl.hpp"
41 #include "prims/jvmtiRedefineClasses.hpp"
42 #include "runtime/deoptimization.hpp"
43 #include "runtime/frame.inline.hpp"
44 #include "runtime/handles.inline.hpp"
45 #include "runtime/interfaceSupport.inline.hpp"
46 #include "runtime/javaCalls.hpp"
47 #include "runtime/os.hpp"
48 #include "runtime/serviceThread.hpp"
49 #include "runtime/signature.hpp"
50 #include "runtime/thread.inline.hpp"
51 #include "runtime/threadSMR.hpp"
52 #include "runtime/vframe.hpp"
53 #include "runtime/vframe_hp.hpp"
54 #include "runtime/vmOperations.hpp"
55 #include "utilities/exceptions.hpp"
56
57 //
58 // class JvmtiAgentThread
59 //
60 // JavaThread used to wrap a thread started by an agent
61 // using the JVMTI method RunAgentThread.
62 //
63
JvmtiAgentThread(JvmtiEnv * env,jvmtiStartFunction start_fn,const void * start_arg)64 JvmtiAgentThread::JvmtiAgentThread(JvmtiEnv* env, jvmtiStartFunction start_fn, const void *start_arg)
65 : JavaThread(start_function_wrapper) {
66 _env = env;
67 _start_fn = start_fn;
68 _start_arg = start_arg;
69 }
70
71 void
start_function_wrapper(JavaThread * thread,TRAPS)72 JvmtiAgentThread::start_function_wrapper(JavaThread *thread, TRAPS) {
73 // It is expected that any Agent threads will be created as
74 // Java Threads. If this is the case, notification of the creation
75 // of the thread is given in JavaThread::thread_main().
76 assert(thread->is_Java_thread(), "debugger thread should be a Java Thread");
77 assert(thread == JavaThread::current(), "sanity check");
78
79 JvmtiAgentThread *dthread = (JvmtiAgentThread *)thread;
80 dthread->call_start_function();
81 }
82
83 void
call_start_function()84 JvmtiAgentThread::call_start_function() {
85 ThreadToNativeFromVM transition(this);
86 _start_fn(_env->jvmti_external(), jni_environment(), (void*)_start_arg);
87 }
88
89
90 //
91 // class GrowableCache - private methods
92 //
93
recache()94 void GrowableCache::recache() {
95 int len = _elements->length();
96
97 FREE_C_HEAP_ARRAY(address, _cache);
98 _cache = NEW_C_HEAP_ARRAY(address,len+1, mtInternal);
99
100 for (int i=0; i<len; i++) {
101 _cache[i] = _elements->at(i)->getCacheValue();
102 //
103 // The cache entry has gone bad. Without a valid frame pointer
104 // value, the entry is useless so we simply delete it in product
105 // mode. The call to remove() will rebuild the cache again
106 // without the bad entry.
107 //
108 if (_cache[i] == NULL) {
109 assert(false, "cannot recache NULL elements");
110 remove(i);
111 return;
112 }
113 }
114 _cache[len] = NULL;
115
116 _listener_fun(_this_obj,_cache);
117 }
118
equals(void * v,GrowableElement * e2)119 bool GrowableCache::equals(void* v, GrowableElement *e2) {
120 GrowableElement *e1 = (GrowableElement *) v;
121 assert(e1 != NULL, "e1 != NULL");
122 assert(e2 != NULL, "e2 != NULL");
123
124 return e1->equals(e2);
125 }
126
127 //
128 // class GrowableCache - public methods
129 //
130
GrowableCache()131 GrowableCache::GrowableCache() {
132 _this_obj = NULL;
133 _listener_fun = NULL;
134 _elements = NULL;
135 _cache = NULL;
136 }
137
~GrowableCache()138 GrowableCache::~GrowableCache() {
139 clear();
140 delete _elements;
141 FREE_C_HEAP_ARRAY(address, _cache);
142 }
143
initialize(void * this_obj,void listener_fun (void *,address *))144 void GrowableCache::initialize(void *this_obj, void listener_fun(void *, address*) ) {
145 _this_obj = this_obj;
146 _listener_fun = listener_fun;
147 _elements = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<GrowableElement*>(5,true);
148 recache();
149 }
150
151 // number of elements in the collection
length()152 int GrowableCache::length() {
153 return _elements->length();
154 }
155
156 // get the value of the index element in the collection
at(int index)157 GrowableElement* GrowableCache::at(int index) {
158 GrowableElement *e = (GrowableElement *) _elements->at(index);
159 assert(e != NULL, "e != NULL");
160 return e;
161 }
162
find(GrowableElement * e)163 int GrowableCache::find(GrowableElement* e) {
164 return _elements->find(e, GrowableCache::equals);
165 }
166
167 // append a copy of the element to the end of the collection
append(GrowableElement * e)168 void GrowableCache::append(GrowableElement* e) {
169 GrowableElement *new_e = e->clone();
170 _elements->append(new_e);
171 recache();
172 }
173
174 // insert a copy of the element using lessthan()
insert(GrowableElement * e)175 void GrowableCache::insert(GrowableElement* e) {
176 GrowableElement *new_e = e->clone();
177 _elements->append(new_e);
178
179 int n = length()-2;
180 for (int i=n; i>=0; i--) {
181 GrowableElement *e1 = _elements->at(i);
182 GrowableElement *e2 = _elements->at(i+1);
183 if (e2->lessThan(e1)) {
184 _elements->at_put(i+1, e1);
185 _elements->at_put(i, e2);
186 }
187 }
188
189 recache();
190 }
191
192 // remove the element at index
remove(int index)193 void GrowableCache::remove (int index) {
194 GrowableElement *e = _elements->at(index);
195 assert(e != NULL, "e != NULL");
196 _elements->remove(e);
197 delete e;
198 recache();
199 }
200
201 // clear out all elements, release all heap space and
202 // let our listener know that things have changed.
clear()203 void GrowableCache::clear() {
204 int len = _elements->length();
205 for (int i=0; i<len; i++) {
206 delete _elements->at(i);
207 }
208 _elements->clear();
209 recache();
210 }
211
oops_do(OopClosure * f)212 void GrowableCache::oops_do(OopClosure* f) {
213 int len = _elements->length();
214 for (int i=0; i<len; i++) {
215 GrowableElement *e = _elements->at(i);
216 e->oops_do(f);
217 }
218 }
219
metadata_do(void f (Metadata *))220 void GrowableCache::metadata_do(void f(Metadata*)) {
221 int len = _elements->length();
222 for (int i=0; i<len; i++) {
223 GrowableElement *e = _elements->at(i);
224 e->metadata_do(f);
225 }
226 }
227
228 //
229 // class JvmtiBreakpoint
230 //
231
JvmtiBreakpoint()232 JvmtiBreakpoint::JvmtiBreakpoint() {
233 _method = NULL;
234 _bci = 0;
235 _class_holder = NULL;
236 }
237
JvmtiBreakpoint(Method * m_method,jlocation location)238 JvmtiBreakpoint::JvmtiBreakpoint(Method* m_method, jlocation location) {
239 _method = m_method;
240 _class_holder = _method->method_holder()->klass_holder();
241 #ifdef CHECK_UNHANDLED_OOPS
242 // _class_holder can't be wrapped in a Handle, because JvmtiBreakpoints are
243 // sometimes allocated on the heap.
244 //
245 // The code handling JvmtiBreakpoints allocated on the stack can't be
246 // interrupted by a GC until _class_holder is reachable by the GC via the
247 // oops_do method.
248 Thread::current()->allow_unhandled_oop(&_class_holder);
249 #endif // CHECK_UNHANDLED_OOPS
250 assert(_method != NULL, "_method != NULL");
251 _bci = (int) location;
252 assert(_bci >= 0, "_bci >= 0");
253 }
254
copy(JvmtiBreakpoint & bp)255 void JvmtiBreakpoint::copy(JvmtiBreakpoint& bp) {
256 _method = bp._method;
257 _bci = bp._bci;
258 _class_holder = bp._class_holder;
259 }
260
lessThan(JvmtiBreakpoint & bp)261 bool JvmtiBreakpoint::lessThan(JvmtiBreakpoint& bp) {
262 Unimplemented();
263 return false;
264 }
265
equals(JvmtiBreakpoint & bp)266 bool JvmtiBreakpoint::equals(JvmtiBreakpoint& bp) {
267 return _method == bp._method
268 && _bci == bp._bci;
269 }
270
is_valid()271 bool JvmtiBreakpoint::is_valid() {
272 // class loader can be NULL
273 return _method != NULL &&
274 _bci >= 0;
275 }
276
getBcp() const277 address JvmtiBreakpoint::getBcp() const {
278 return _method->bcp_from(_bci);
279 }
280
each_method_version_do(method_action meth_act)281 void JvmtiBreakpoint::each_method_version_do(method_action meth_act) {
282 ((Method*)_method->*meth_act)(_bci);
283
284 // add/remove breakpoint to/from versions of the method that are EMCP.
285 Thread *thread = Thread::current();
286 InstanceKlass* ik = _method->method_holder();
287 Symbol* m_name = _method->name();
288 Symbol* m_signature = _method->signature();
289
290 // search previous versions if they exist
291 for (InstanceKlass* pv_node = ik->previous_versions();
292 pv_node != NULL;
293 pv_node = pv_node->previous_versions()) {
294 Array<Method*>* methods = pv_node->methods();
295
296 for (int i = methods->length() - 1; i >= 0; i--) {
297 Method* method = methods->at(i);
298 // Only set breakpoints in running EMCP methods.
299 if (method->is_running_emcp() &&
300 method->name() == m_name &&
301 method->signature() == m_signature) {
302 ResourceMark rm;
303 log_debug(redefine, class, breakpoint)
304 ("%sing breakpoint in %s(%s)", meth_act == &Method::set_breakpoint ? "sett" : "clear",
305 method->name()->as_C_string(), method->signature()->as_C_string());
306 (method->*meth_act)(_bci);
307 break;
308 }
309 }
310 }
311 }
312
set()313 void JvmtiBreakpoint::set() {
314 each_method_version_do(&Method::set_breakpoint);
315 }
316
clear()317 void JvmtiBreakpoint::clear() {
318 each_method_version_do(&Method::clear_breakpoint);
319 }
320
print_on(outputStream * out) const321 void JvmtiBreakpoint::print_on(outputStream* out) const {
322 #ifndef PRODUCT
323 ResourceMark rm;
324 const char *class_name = (_method == NULL) ? "NULL" : _method->klass_name()->as_C_string();
325 const char *method_name = (_method == NULL) ? "NULL" : _method->name()->as_C_string();
326 out->print("Breakpoint(%s,%s,%d,%p)", class_name, method_name, _bci, getBcp());
327 #endif
328 }
329
330
331 //
332 // class VM_ChangeBreakpoints
333 //
334 // Modify the Breakpoints data structure at a safepoint
335 //
336
doit()337 void VM_ChangeBreakpoints::doit() {
338 switch (_operation) {
339 case SET_BREAKPOINT:
340 _breakpoints->set_at_safepoint(*_bp);
341 break;
342 case CLEAR_BREAKPOINT:
343 _breakpoints->clear_at_safepoint(*_bp);
344 break;
345 default:
346 assert(false, "Unknown operation");
347 }
348 }
349
oops_do(OopClosure * f)350 void VM_ChangeBreakpoints::oops_do(OopClosure* f) {
351 // The JvmtiBreakpoints in _breakpoints will be visited via
352 // JvmtiExport::oops_do.
353 if (_bp != NULL) {
354 _bp->oops_do(f);
355 }
356 }
357
metadata_do(void f (Metadata *))358 void VM_ChangeBreakpoints::metadata_do(void f(Metadata*)) {
359 // Walk metadata in breakpoints to keep from being deallocated with RedefineClasses
360 if (_bp != NULL) {
361 _bp->metadata_do(f);
362 }
363 }
364
365 //
366 // class JvmtiBreakpoints
367 //
368 // a JVMTI internal collection of JvmtiBreakpoint
369 //
370
JvmtiBreakpoints(void listener_fun (void *,address *))371 JvmtiBreakpoints::JvmtiBreakpoints(void listener_fun(void *,address *)) {
372 _bps.initialize(this,listener_fun);
373 }
374
~JvmtiBreakpoints()375 JvmtiBreakpoints:: ~JvmtiBreakpoints() {}
376
oops_do(OopClosure * f)377 void JvmtiBreakpoints::oops_do(OopClosure* f) {
378 _bps.oops_do(f);
379 }
380
metadata_do(void f (Metadata *))381 void JvmtiBreakpoints::metadata_do(void f(Metadata*)) {
382 _bps.metadata_do(f);
383 }
384
print()385 void JvmtiBreakpoints::print() {
386 #ifndef PRODUCT
387 LogTarget(Trace, jvmti) log;
388 LogStream log_stream(log);
389
390 int n = _bps.length();
391 for (int i=0; i<n; i++) {
392 JvmtiBreakpoint& bp = _bps.at(i);
393 log_stream.print("%d: ", i);
394 bp.print_on(&log_stream);
395 log_stream.cr();
396 }
397 #endif
398 }
399
400
set_at_safepoint(JvmtiBreakpoint & bp)401 void JvmtiBreakpoints::set_at_safepoint(JvmtiBreakpoint& bp) {
402 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
403
404 int i = _bps.find(bp);
405 if (i == -1) {
406 _bps.append(bp);
407 bp.set();
408 }
409 }
410
clear_at_safepoint(JvmtiBreakpoint & bp)411 void JvmtiBreakpoints::clear_at_safepoint(JvmtiBreakpoint& bp) {
412 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
413
414 int i = _bps.find(bp);
415 if (i != -1) {
416 _bps.remove(i);
417 bp.clear();
418 }
419 }
420
length()421 int JvmtiBreakpoints::length() { return _bps.length(); }
422
set(JvmtiBreakpoint & bp)423 int JvmtiBreakpoints::set(JvmtiBreakpoint& bp) {
424 if ( _bps.find(bp) != -1) {
425 return JVMTI_ERROR_DUPLICATE;
426 }
427 VM_ChangeBreakpoints set_breakpoint(VM_ChangeBreakpoints::SET_BREAKPOINT, &bp);
428 VMThread::execute(&set_breakpoint);
429 return JVMTI_ERROR_NONE;
430 }
431
clear(JvmtiBreakpoint & bp)432 int JvmtiBreakpoints::clear(JvmtiBreakpoint& bp) {
433 if ( _bps.find(bp) == -1) {
434 return JVMTI_ERROR_NOT_FOUND;
435 }
436
437 VM_ChangeBreakpoints clear_breakpoint(VM_ChangeBreakpoints::CLEAR_BREAKPOINT, &bp);
438 VMThread::execute(&clear_breakpoint);
439 return JVMTI_ERROR_NONE;
440 }
441
clearall_in_class_at_safepoint(Klass * klass)442 void JvmtiBreakpoints::clearall_in_class_at_safepoint(Klass* klass) {
443 bool changed = true;
444 // We are going to run thru the list of bkpts
445 // and delete some. This deletion probably alters
446 // the list in some implementation defined way such
447 // that when we delete entry i, the next entry might
448 // no longer be at i+1. To be safe, each time we delete
449 // an entry, we'll just start again from the beginning.
450 // We'll stop when we make a pass thru the whole list without
451 // deleting anything.
452 while (changed) {
453 int len = _bps.length();
454 changed = false;
455 for (int i = 0; i < len; i++) {
456 JvmtiBreakpoint& bp = _bps.at(i);
457 if (bp.method()->method_holder() == klass) {
458 bp.clear();
459 _bps.remove(i);
460 // This changed 'i' so we have to start over.
461 changed = true;
462 break;
463 }
464 }
465 }
466 }
467
468 //
469 // class JvmtiCurrentBreakpoints
470 //
471
472 JvmtiBreakpoints *JvmtiCurrentBreakpoints::_jvmti_breakpoints = NULL;
473 address * JvmtiCurrentBreakpoints::_breakpoint_list = NULL;
474
475
get_jvmti_breakpoints()476 JvmtiBreakpoints& JvmtiCurrentBreakpoints::get_jvmti_breakpoints() {
477 if (_jvmti_breakpoints != NULL) return (*_jvmti_breakpoints);
478 _jvmti_breakpoints = new JvmtiBreakpoints(listener_fun);
479 assert(_jvmti_breakpoints != NULL, "_jvmti_breakpoints != NULL");
480 return (*_jvmti_breakpoints);
481 }
482
listener_fun(void * this_obj,address * cache)483 void JvmtiCurrentBreakpoints::listener_fun(void *this_obj, address *cache) {
484 JvmtiBreakpoints *this_jvmti = (JvmtiBreakpoints *) this_obj;
485 assert(this_jvmti != NULL, "this_jvmti != NULL");
486
487 debug_only(int n = this_jvmti->length(););
488 assert(cache[n] == NULL, "cache must be NULL terminated");
489
490 set_breakpoint_list(cache);
491 }
492
493
oops_do(OopClosure * f)494 void JvmtiCurrentBreakpoints::oops_do(OopClosure* f) {
495 if (_jvmti_breakpoints != NULL) {
496 _jvmti_breakpoints->oops_do(f);
497 }
498 }
499
metadata_do(void f (Metadata *))500 void JvmtiCurrentBreakpoints::metadata_do(void f(Metadata*)) {
501 if (_jvmti_breakpoints != NULL) {
502 _jvmti_breakpoints->metadata_do(f);
503 }
504 }
505
506 ///////////////////////////////////////////////////////////////
507 //
508 // class VM_GetOrSetLocal
509 //
510
511 // Constructor for non-object getter
VM_GetOrSetLocal(JavaThread * thread,jint depth,jint index,BasicType type)512 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, jint index, BasicType type)
513 : _thread(thread)
514 , _calling_thread(NULL)
515 , _depth(depth)
516 , _index(index)
517 , _type(type)
518 , _jvf(NULL)
519 , _set(false)
520 , _result(JVMTI_ERROR_NONE)
521 {
522 }
523
524 // Constructor for object or non-object setter
VM_GetOrSetLocal(JavaThread * thread,jint depth,jint index,BasicType type,jvalue value)525 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, jint index, BasicType type, jvalue value)
526 : _thread(thread)
527 , _calling_thread(NULL)
528 , _depth(depth)
529 , _index(index)
530 , _type(type)
531 , _value(value)
532 , _jvf(NULL)
533 , _set(true)
534 , _result(JVMTI_ERROR_NONE)
535 {
536 }
537
538 // Constructor for object getter
VM_GetOrSetLocal(JavaThread * thread,JavaThread * calling_thread,jint depth,int index)539 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, JavaThread* calling_thread, jint depth, int index)
540 : _thread(thread)
541 , _calling_thread(calling_thread)
542 , _depth(depth)
543 , _index(index)
544 , _type(T_OBJECT)
545 , _jvf(NULL)
546 , _set(false)
547 , _result(JVMTI_ERROR_NONE)
548 {
549 }
550
get_vframe()551 vframe *VM_GetOrSetLocal::get_vframe() {
552 if (!_thread->has_last_Java_frame()) {
553 return NULL;
554 }
555 RegisterMap reg_map(_thread);
556 vframe *vf = _thread->last_java_vframe(®_map);
557 int d = 0;
558 while ((vf != NULL) && (d < _depth)) {
559 vf = vf->java_sender();
560 d++;
561 }
562 return vf;
563 }
564
get_java_vframe()565 javaVFrame *VM_GetOrSetLocal::get_java_vframe() {
566 vframe* vf = get_vframe();
567 if (vf == NULL) {
568 _result = JVMTI_ERROR_NO_MORE_FRAMES;
569 return NULL;
570 }
571 javaVFrame *jvf = (javaVFrame*)vf;
572
573 if (!vf->is_java_frame()) {
574 _result = JVMTI_ERROR_OPAQUE_FRAME;
575 return NULL;
576 }
577 return jvf;
578 }
579
580 // Check that the klass is assignable to a type with the given signature.
581 // Another solution could be to use the function Klass::is_subtype_of(type).
582 // But the type class can be forced to load/initialize eagerly in such a case.
583 // This may cause unexpected consequences like CFLH or class-init JVMTI events.
584 // It is better to avoid such a behavior.
is_assignable(const char * ty_sign,Klass * klass,Thread * thread)585 bool VM_GetOrSetLocal::is_assignable(const char* ty_sign, Klass* klass, Thread* thread) {
586 assert(ty_sign != NULL, "type signature must not be NULL");
587 assert(thread != NULL, "thread must not be NULL");
588 assert(klass != NULL, "klass must not be NULL");
589
590 int len = (int) strlen(ty_sign);
591 if (ty_sign[0] == JVM_SIGNATURE_CLASS &&
592 ty_sign[len-1] == JVM_SIGNATURE_ENDCLASS) { // Need pure class/interface name
593 ty_sign++;
594 len -= 2;
595 }
596 TempNewSymbol ty_sym = SymbolTable::new_symbol(ty_sign, len);
597 if (klass->name() == ty_sym) {
598 return true;
599 }
600 // Compare primary supers
601 int super_depth = klass->super_depth();
602 int idx;
603 for (idx = 0; idx < super_depth; idx++) {
604 if (klass->primary_super_of_depth(idx)->name() == ty_sym) {
605 return true;
606 }
607 }
608 // Compare secondary supers
609 const Array<Klass*>* sec_supers = klass->secondary_supers();
610 for (idx = 0; idx < sec_supers->length(); idx++) {
611 if (((Klass*) sec_supers->at(idx))->name() == ty_sym) {
612 return true;
613 }
614 }
615 return false;
616 }
617
618 // Checks error conditions:
619 // JVMTI_ERROR_INVALID_SLOT
620 // JVMTI_ERROR_TYPE_MISMATCH
621 // Returns: 'true' - everything is Ok, 'false' - error code
622
check_slot_type_lvt(javaVFrame * jvf)623 bool VM_GetOrSetLocal::check_slot_type_lvt(javaVFrame* jvf) {
624 Method* method_oop = jvf->method();
625 jint num_entries = method_oop->localvariable_table_length();
626 if (num_entries == 0) {
627 _result = JVMTI_ERROR_INVALID_SLOT;
628 return false; // There are no slots
629 }
630 int signature_idx = -1;
631 int vf_bci = jvf->bci();
632 LocalVariableTableElement* table = method_oop->localvariable_table_start();
633 for (int i = 0; i < num_entries; i++) {
634 int start_bci = table[i].start_bci;
635 int end_bci = start_bci + table[i].length;
636
637 // Here we assume that locations of LVT entries
638 // with the same slot number cannot be overlapped
639 if (_index == (jint) table[i].slot && start_bci <= vf_bci && vf_bci <= end_bci) {
640 signature_idx = (int) table[i].descriptor_cp_index;
641 break;
642 }
643 }
644 if (signature_idx == -1) {
645 _result = JVMTI_ERROR_INVALID_SLOT;
646 return false; // Incorrect slot index
647 }
648 Symbol* sign_sym = method_oop->constants()->symbol_at(signature_idx);
649 const char* signature = (const char *) sign_sym->as_utf8();
650 BasicType slot_type = char2type(signature[0]);
651
652 switch (slot_type) {
653 case T_BYTE:
654 case T_SHORT:
655 case T_CHAR:
656 case T_BOOLEAN:
657 slot_type = T_INT;
658 break;
659 case T_ARRAY:
660 slot_type = T_OBJECT;
661 break;
662 default:
663 break;
664 };
665 if (_type != slot_type) {
666 _result = JVMTI_ERROR_TYPE_MISMATCH;
667 return false;
668 }
669
670 jobject jobj = _value.l;
671 if (_set && slot_type == T_OBJECT && jobj != NULL) { // NULL reference is allowed
672 // Check that the jobject class matches the return type signature.
673 JavaThread* cur_thread = JavaThread::current();
674 HandleMark hm(cur_thread);
675
676 Handle obj(cur_thread, JNIHandles::resolve_external_guard(jobj));
677 NULL_CHECK(obj, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
678 Klass* ob_k = obj->klass();
679 NULL_CHECK(ob_k, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
680
681 if (!is_assignable(signature, ob_k, cur_thread)) {
682 _result = JVMTI_ERROR_TYPE_MISMATCH;
683 return false;
684 }
685 }
686 return true;
687 }
688
check_slot_type_no_lvt(javaVFrame * jvf)689 bool VM_GetOrSetLocal::check_slot_type_no_lvt(javaVFrame* jvf) {
690 Method* method_oop = jvf->method();
691 jint extra_slot = (_type == T_LONG || _type == T_DOUBLE) ? 1 : 0;
692
693 if (_index < 0 || _index + extra_slot >= method_oop->max_locals()) {
694 _result = JVMTI_ERROR_INVALID_SLOT;
695 return false;
696 }
697 StackValueCollection *locals = _jvf->locals();
698 BasicType slot_type = locals->at(_index)->type();
699
700 if (slot_type == T_CONFLICT) {
701 _result = JVMTI_ERROR_INVALID_SLOT;
702 return false;
703 }
704 if (extra_slot) {
705 BasicType extra_slot_type = locals->at(_index + 1)->type();
706 if (extra_slot_type != T_INT) {
707 _result = JVMTI_ERROR_INVALID_SLOT;
708 return false;
709 }
710 }
711 if (_type != slot_type && (_type == T_OBJECT || slot_type != T_INT)) {
712 _result = JVMTI_ERROR_TYPE_MISMATCH;
713 return false;
714 }
715 return true;
716 }
717
can_be_deoptimized(vframe * vf)718 static bool can_be_deoptimized(vframe* vf) {
719 return (vf->is_compiled_frame() && vf->fr().can_be_deoptimized());
720 }
721
doit_prologue()722 bool VM_GetOrSetLocal::doit_prologue() {
723 _jvf = get_java_vframe();
724 NULL_CHECK(_jvf, false);
725
726 Method* method_oop = _jvf->method();
727 if (getting_receiver()) {
728 if (method_oop->is_static()) {
729 _result = JVMTI_ERROR_INVALID_SLOT;
730 return false;
731 }
732 return true;
733 }
734
735 if (method_oop->is_native()) {
736 _result = JVMTI_ERROR_OPAQUE_FRAME;
737 return false;
738 }
739
740 if (!check_slot_type_no_lvt(_jvf)) {
741 return false;
742 }
743 if (method_oop->has_localvariable_table()) {
744 return check_slot_type_lvt(_jvf);
745 }
746 return true;
747 }
748
doit()749 void VM_GetOrSetLocal::doit() {
750 InterpreterOopMap oop_mask;
751 _jvf->method()->mask_for(_jvf->bci(), &oop_mask);
752 if (oop_mask.is_dead(_index)) {
753 // The local can be invalid and uninitialized in the scope of current bci
754 _result = JVMTI_ERROR_INVALID_SLOT;
755 return;
756 }
757 if (_set) {
758 // Force deoptimization of frame if compiled because it's
759 // possible the compiler emitted some locals as constant values,
760 // meaning they are not mutable.
761 if (can_be_deoptimized(_jvf)) {
762
763 // Schedule deoptimization so that eventually the local
764 // update will be written to an interpreter frame.
765 Deoptimization::deoptimize_frame(_jvf->thread(), _jvf->fr().id());
766
767 // Now store a new value for the local which will be applied
768 // once deoptimization occurs. Note however that while this
769 // write is deferred until deoptimization actually happens
770 // can vframe created after this point will have its locals
771 // reflecting this update so as far as anyone can see the
772 // write has already taken place.
773
774 // If we are updating an oop then get the oop from the handle
775 // since the handle will be long gone by the time the deopt
776 // happens. The oop stored in the deferred local will be
777 // gc'd on its own.
778 if (_type == T_OBJECT) {
779 _value.l = (jobject) (JNIHandles::resolve_external_guard(_value.l));
780 }
781 // Re-read the vframe so we can see that it is deoptimized
782 // [ Only need because of assert in update_local() ]
783 _jvf = get_java_vframe();
784 ((compiledVFrame*)_jvf)->update_local(_type, _index, _value);
785 return;
786 }
787 StackValueCollection *locals = _jvf->locals();
788 HandleMark hm;
789
790 switch (_type) {
791 case T_INT: locals->set_int_at (_index, _value.i); break;
792 case T_LONG: locals->set_long_at (_index, _value.j); break;
793 case T_FLOAT: locals->set_float_at (_index, _value.f); break;
794 case T_DOUBLE: locals->set_double_at(_index, _value.d); break;
795 case T_OBJECT: {
796 Handle ob_h(Thread::current(), JNIHandles::resolve_external_guard(_value.l));
797 locals->set_obj_at (_index, ob_h);
798 break;
799 }
800 default: ShouldNotReachHere();
801 }
802 _jvf->set_locals(locals);
803 } else {
804 if (_jvf->method()->is_native() && _jvf->is_compiled_frame()) {
805 assert(getting_receiver(), "Can only get here when getting receiver");
806 oop receiver = _jvf->fr().get_native_receiver();
807 _value.l = JNIHandles::make_local(_calling_thread, receiver);
808 } else {
809 StackValueCollection *locals = _jvf->locals();
810
811 switch (_type) {
812 case T_INT: _value.i = locals->int_at (_index); break;
813 case T_LONG: _value.j = locals->long_at (_index); break;
814 case T_FLOAT: _value.f = locals->float_at (_index); break;
815 case T_DOUBLE: _value.d = locals->double_at(_index); break;
816 case T_OBJECT: {
817 // Wrap the oop to be returned in a local JNI handle since
818 // oops_do() no longer applies after doit() is finished.
819 oop obj = locals->obj_at(_index)();
820 _value.l = JNIHandles::make_local(_calling_thread, obj);
821 break;
822 }
823 default: ShouldNotReachHere();
824 }
825 }
826 }
827 }
828
829
allow_nested_vm_operations() const830 bool VM_GetOrSetLocal::allow_nested_vm_operations() const {
831 return true; // May need to deoptimize
832 }
833
834
VM_GetReceiver(JavaThread * thread,JavaThread * caller_thread,jint depth)835 VM_GetReceiver::VM_GetReceiver(
836 JavaThread* thread, JavaThread* caller_thread, jint depth)
837 : VM_GetOrSetLocal(thread, caller_thread, depth, 0) {}
838
839 /////////////////////////////////////////////////////////////////////////////////////////
840
841 //
842 // class JvmtiSuspendControl - see comments in jvmtiImpl.hpp
843 //
844
suspend(JavaThread * java_thread)845 bool JvmtiSuspendControl::suspend(JavaThread *java_thread) {
846 // external suspend should have caught suspending a thread twice
847
848 // Immediate suspension required for JPDA back-end so JVMTI agent threads do
849 // not deadlock due to later suspension on transitions while holding
850 // raw monitors. Passing true causes the immediate suspension.
851 // java_suspend() will catch threads in the process of exiting
852 // and will ignore them.
853 java_thread->java_suspend();
854
855 // It would be nice to have the following assertion in all the time,
856 // but it is possible for a racing resume request to have resumed
857 // this thread right after we suspended it. Temporarily enable this
858 // assertion if you are chasing a different kind of bug.
859 //
860 // assert(java_lang_Thread::thread(java_thread->threadObj()) == NULL ||
861 // java_thread->is_being_ext_suspended(), "thread is not suspended");
862
863 if (java_lang_Thread::thread(java_thread->threadObj()) == NULL) {
864 // check again because we can get delayed in java_suspend():
865 // the thread is in process of exiting.
866 return false;
867 }
868
869 return true;
870 }
871
resume(JavaThread * java_thread)872 bool JvmtiSuspendControl::resume(JavaThread *java_thread) {
873 // external suspend should have caught resuming a thread twice
874 assert(java_thread->is_being_ext_suspended(), "thread should be suspended");
875
876 // resume thread
877 {
878 // must always grab Threads_lock, see JVM_SuspendThread
879 MutexLocker ml(Threads_lock);
880 java_thread->java_resume();
881 }
882
883 return true;
884 }
885
886
print()887 void JvmtiSuspendControl::print() {
888 #ifndef PRODUCT
889 ResourceMark rm;
890 LogStreamHandle(Trace, jvmti) log_stream;
891 log_stream.print("Suspended Threads: [");
892 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
893 #ifdef JVMTI_TRACE
894 const char *name = JvmtiTrace::safe_get_thread_name(thread);
895 #else
896 const char *name = "";
897 #endif /*JVMTI_TRACE */
898 log_stream.print("%s(%c ", name, thread->is_being_ext_suspended() ? 'S' : '_');
899 if (!thread->has_last_Java_frame()) {
900 log_stream.print("no stack");
901 }
902 log_stream.print(") ");
903 }
904 log_stream.print_cr("]");
905 #endif
906 }
907
compiled_method_load_event(nmethod * nm)908 JvmtiDeferredEvent JvmtiDeferredEvent::compiled_method_load_event(
909 nmethod* nm) {
910 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_COMPILED_METHOD_LOAD);
911 event._event_data.compiled_method_load = nm;
912 return event;
913 }
914
compiled_method_unload_event(jmethodID id,const void * code)915 JvmtiDeferredEvent JvmtiDeferredEvent::compiled_method_unload_event(
916 jmethodID id, const void* code) {
917 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_COMPILED_METHOD_UNLOAD);
918 event._event_data.compiled_method_unload.method_id = id;
919 event._event_data.compiled_method_unload.code_begin = code;
920 return event;
921 }
922
dynamic_code_generated_event(const char * name,const void * code_begin,const void * code_end)923 JvmtiDeferredEvent JvmtiDeferredEvent::dynamic_code_generated_event(
924 const char* name, const void* code_begin, const void* code_end) {
925 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_DYNAMIC_CODE_GENERATED);
926 // Need to make a copy of the name since we don't know how long
927 // the event poster will keep it around after we enqueue the
928 // deferred event and return. strdup() failure is handled in
929 // the post() routine below.
930 event._event_data.dynamic_code_generated.name = os::strdup(name);
931 event._event_data.dynamic_code_generated.code_begin = code_begin;
932 event._event_data.dynamic_code_generated.code_end = code_end;
933 return event;
934 }
935
class_unload_event(const char * name)936 JvmtiDeferredEvent JvmtiDeferredEvent::class_unload_event(const char* name) {
937 JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_CLASS_UNLOAD);
938 // Need to make a copy of the name since we don't know how long
939 // the event poster will keep it around after we enqueue the
940 // deferred event and return. strdup() failure is handled in
941 // the post() routine below.
942 event._event_data.class_unload.name = os::strdup(name);
943 return event;
944 }
945
post()946 void JvmtiDeferredEvent::post() {
947 assert(Thread::current()->is_service_thread(),
948 "Service thread must post enqueued events");
949 switch(_type) {
950 case TYPE_COMPILED_METHOD_LOAD: {
951 nmethod* nm = _event_data.compiled_method_load;
952 JvmtiExport::post_compiled_method_load(nm);
953 break;
954 }
955 case TYPE_COMPILED_METHOD_UNLOAD: {
956 JvmtiExport::post_compiled_method_unload(
957 _event_data.compiled_method_unload.method_id,
958 _event_data.compiled_method_unload.code_begin);
959 break;
960 }
961 case TYPE_DYNAMIC_CODE_GENERATED: {
962 JvmtiExport::post_dynamic_code_generated_internal(
963 // if strdup failed give the event a default name
964 (_event_data.dynamic_code_generated.name == NULL)
965 ? "unknown_code" : _event_data.dynamic_code_generated.name,
966 _event_data.dynamic_code_generated.code_begin,
967 _event_data.dynamic_code_generated.code_end);
968 if (_event_data.dynamic_code_generated.name != NULL) {
969 // release our copy
970 os::free((void *)_event_data.dynamic_code_generated.name);
971 }
972 break;
973 }
974 case TYPE_CLASS_UNLOAD: {
975 JvmtiExport::post_class_unload_internal(
976 // if strdup failed give the event a default name
977 (_event_data.class_unload.name == NULL)
978 ? "unknown_class" : _event_data.class_unload.name);
979 if (_event_data.class_unload.name != NULL) {
980 // release our copy
981 os::free((void *)_event_data.class_unload.name);
982 }
983 break;
984 }
985 default:
986 ShouldNotReachHere();
987 }
988 }
989
post_compiled_method_load_event(JvmtiEnv * env)990 void JvmtiDeferredEvent::post_compiled_method_load_event(JvmtiEnv* env) {
991 assert(_type == TYPE_COMPILED_METHOD_LOAD, "only user of this method");
992 nmethod* nm = _event_data.compiled_method_load;
993 JvmtiExport::post_compiled_method_load(env, nm);
994 }
995
run_nmethod_entry_barriers()996 void JvmtiDeferredEvent::run_nmethod_entry_barriers() {
997 if (_type == TYPE_COMPILED_METHOD_LOAD) {
998 _event_data.compiled_method_load->run_nmethod_entry_barrier();
999 }
1000 }
1001
1002
1003 // Keep the nmethod for compiled_method_load from being unloaded.
oops_do(OopClosure * f,CodeBlobClosure * cf)1004 void JvmtiDeferredEvent::oops_do(OopClosure* f, CodeBlobClosure* cf) {
1005 if (cf != NULL && _type == TYPE_COMPILED_METHOD_LOAD) {
1006 cf->do_code_blob(_event_data.compiled_method_load);
1007 }
1008 }
1009
1010 // The sweeper calls this and marks the nmethods here on the stack so that
1011 // they cannot be turned into zombies while in the queue.
nmethods_do(CodeBlobClosure * cf)1012 void JvmtiDeferredEvent::nmethods_do(CodeBlobClosure* cf) {
1013 if (cf != NULL && _type == TYPE_COMPILED_METHOD_LOAD) {
1014 cf->do_code_blob(_event_data.compiled_method_load);
1015 }
1016 }
1017
1018
has_events()1019 bool JvmtiDeferredEventQueue::has_events() {
1020 // We save the queued events before the live phase and post them when it starts.
1021 // This code could skip saving the events on the queue before the live
1022 // phase and ignore them, but this would change how we do things now.
1023 // Starting the service thread earlier causes this to be called before the live phase begins.
1024 // The events on the queue should all be posted after the live phase so this is an
1025 // ok check. Before the live phase, DynamicCodeGenerated events are posted directly.
1026 // If we add other types of events to the deferred queue, this could get ugly.
1027 return JvmtiEnvBase::get_phase() == JVMTI_PHASE_LIVE && _queue_head != NULL;
1028 }
1029
enqueue(JvmtiDeferredEvent event)1030 void JvmtiDeferredEventQueue::enqueue(JvmtiDeferredEvent event) {
1031 // Events get added to the end of the queue (and are pulled off the front).
1032 QueueNode* node = new QueueNode(event);
1033 if (_queue_tail == NULL) {
1034 _queue_tail = _queue_head = node;
1035 } else {
1036 assert(_queue_tail->next() == NULL, "Must be the last element in the list");
1037 _queue_tail->set_next(node);
1038 _queue_tail = node;
1039 }
1040
1041 assert((_queue_head == NULL) == (_queue_tail == NULL),
1042 "Inconsistent queue markers");
1043 }
1044
dequeue()1045 JvmtiDeferredEvent JvmtiDeferredEventQueue::dequeue() {
1046 assert(_queue_head != NULL, "Nothing to dequeue");
1047
1048 if (_queue_head == NULL) {
1049 // Just in case this happens in product; it shouldn't but let's not crash
1050 return JvmtiDeferredEvent();
1051 }
1052
1053 QueueNode* node = _queue_head;
1054 _queue_head = _queue_head->next();
1055 if (_queue_head == NULL) {
1056 _queue_tail = NULL;
1057 }
1058
1059 assert((_queue_head == NULL) == (_queue_tail == NULL),
1060 "Inconsistent queue markers");
1061
1062 JvmtiDeferredEvent event = node->event();
1063 delete node;
1064 return event;
1065 }
1066
post(JvmtiEnv * env)1067 void JvmtiDeferredEventQueue::post(JvmtiEnv* env) {
1068 // Post and destroy queue nodes
1069 while (_queue_head != NULL) {
1070 JvmtiDeferredEvent event = dequeue();
1071 event.post_compiled_method_load_event(env);
1072 }
1073 }
1074
run_nmethod_entry_barriers()1075 void JvmtiDeferredEventQueue::run_nmethod_entry_barriers() {
1076 for(QueueNode* node = _queue_head; node != NULL; node = node->next()) {
1077 node->event().run_nmethod_entry_barriers();
1078 }
1079 }
1080
1081
oops_do(OopClosure * f,CodeBlobClosure * cf)1082 void JvmtiDeferredEventQueue::oops_do(OopClosure* f, CodeBlobClosure* cf) {
1083 for(QueueNode* node = _queue_head; node != NULL; node = node->next()) {
1084 node->event().oops_do(f, cf);
1085 }
1086 }
1087
nmethods_do(CodeBlobClosure * cf)1088 void JvmtiDeferredEventQueue::nmethods_do(CodeBlobClosure* cf) {
1089 for(QueueNode* node = _queue_head; node != NULL; node = node->next()) {
1090 node->event().nmethods_do(cf);
1091 }
1092 }
1093