rev 47862 : imported patch 10.07.open.rebase_20171110.dcubed

   1 /*
   2  * Copyright (c) 2003, 2017, 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 "interpreter/oopMapCache.hpp"
  29 #include "jvmtifiles/jvmtiEnv.hpp"
  30 #include "logging/log.hpp"
  31 #include "logging/logStream.hpp"
  32 #include "memory/resourceArea.hpp"
  33 #include "oops/instanceKlass.hpp"
  34 #include "oops/oop.inline.hpp"
  35 #include "prims/jvmtiAgentThread.hpp"
  36 #include "prims/jvmtiEventController.inline.hpp"
  37 #include "prims/jvmtiImpl.hpp"
  38 #include "prims/jvmtiRedefineClasses.hpp"
  39 #include "runtime/atomic.hpp"
  40 #include "runtime/deoptimization.hpp"
  41 #include "runtime/handles.hpp"
  42 #include "runtime/handles.inline.hpp"
  43 #include "runtime/interfaceSupport.hpp"
  44 #include "runtime/javaCalls.hpp"
  45 #include "runtime/os.hpp"
  46 #include "runtime/serviceThread.hpp"
  47 #include "runtime/signature.hpp"
  48 #include "runtime/thread.inline.hpp"
  49 #include "runtime/threadSMR.hpp"
  50 #include "runtime/vframe.hpp"
  51 #include "runtime/vframe_hp.hpp"
  52 #include "runtime/vm_operations.hpp"
  53 #include "utilities/exceptions.hpp"
  54 
  55 //
  56 // class JvmtiAgentThread
  57 //
  58 // JavaThread used to wrap a thread started by an agent
  59 // using the JVMTI method RunAgentThread.
  60 //
  61 
  62 JvmtiAgentThread::JvmtiAgentThread(JvmtiEnv* env, jvmtiStartFunction start_fn, const void *start_arg)
  63     : JavaThread(start_function_wrapper) {
  64     _env = env;
  65     _start_fn = start_fn;
  66     _start_arg = start_arg;
  67 }
  68 
  69 void
  70 JvmtiAgentThread::start_function_wrapper(JavaThread *thread, TRAPS) {
  71     // It is expected that any Agent threads will be created as
  72     // Java Threads.  If this is the case, notification of the creation
  73     // of the thread is given in JavaThread::thread_main().
  74     assert(thread->is_Java_thread(), "debugger thread should be a Java Thread");
  75     assert(thread == JavaThread::current(), "sanity check");
  76 
  77     JvmtiAgentThread *dthread = (JvmtiAgentThread *)thread;
  78     dthread->call_start_function();
  79 }
  80 
  81 void
  82 JvmtiAgentThread::call_start_function() {
  83     ThreadToNativeFromVM transition(this);
  84     _start_fn(_env->jvmti_external(), jni_environment(), (void*)_start_arg);
  85 }
  86 
  87 
  88 //
  89 // class GrowableCache - private methods
  90 //
  91 
  92 void GrowableCache::recache() {
  93   int len = _elements->length();
  94 
  95   FREE_C_HEAP_ARRAY(address, _cache);
  96   _cache = NEW_C_HEAP_ARRAY(address,len+1, mtInternal);
  97 
  98   for (int i=0; i<len; i++) {
  99     _cache[i] = _elements->at(i)->getCacheValue();
 100     //
 101     // The cache entry has gone bad. Without a valid frame pointer
 102     // value, the entry is useless so we simply delete it in product
 103     // mode. The call to remove() will rebuild the cache again
 104     // without the bad entry.
 105     //
 106     if (_cache[i] == NULL) {
 107       assert(false, "cannot recache NULL elements");
 108       remove(i);
 109       return;
 110     }
 111   }
 112   _cache[len] = NULL;
 113 
 114   _listener_fun(_this_obj,_cache);
 115 }
 116 
 117 bool GrowableCache::equals(void* v, GrowableElement *e2) {
 118   GrowableElement *e1 = (GrowableElement *) v;
 119   assert(e1 != NULL, "e1 != NULL");
 120   assert(e2 != NULL, "e2 != NULL");
 121 
 122   return e1->equals(e2);
 123 }
 124 
 125 //
 126 // class GrowableCache - public methods
 127 //
 128 
 129 GrowableCache::GrowableCache() {
 130   _this_obj       = NULL;
 131   _listener_fun   = NULL;
 132   _elements       = NULL;
 133   _cache          = NULL;
 134 }
 135 
 136 GrowableCache::~GrowableCache() {
 137   clear();
 138   delete _elements;
 139   FREE_C_HEAP_ARRAY(address, _cache);
 140 }
 141 
 142 void GrowableCache::initialize(void *this_obj, void listener_fun(void *, address*) ) {
 143   _this_obj       = this_obj;
 144   _listener_fun   = listener_fun;
 145   _elements       = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<GrowableElement*>(5,true);
 146   recache();
 147 }
 148 
 149 // number of elements in the collection
 150 int GrowableCache::length() {
 151   return _elements->length();
 152 }
 153 
 154 // get the value of the index element in the collection
 155 GrowableElement* GrowableCache::at(int index) {
 156   GrowableElement *e = (GrowableElement *) _elements->at(index);
 157   assert(e != NULL, "e != NULL");
 158   return e;
 159 }
 160 
 161 int GrowableCache::find(GrowableElement* e) {
 162   return _elements->find(e, GrowableCache::equals);
 163 }
 164 
 165 // append a copy of the element to the end of the collection
 166 void GrowableCache::append(GrowableElement* e) {
 167   GrowableElement *new_e = e->clone();
 168   _elements->append(new_e);
 169   recache();
 170 }
 171 
 172 // insert a copy of the element using lessthan()
 173 void GrowableCache::insert(GrowableElement* e) {
 174   GrowableElement *new_e = e->clone();
 175   _elements->append(new_e);
 176 
 177   int n = length()-2;
 178   for (int i=n; i>=0; i--) {
 179     GrowableElement *e1 = _elements->at(i);
 180     GrowableElement *e2 = _elements->at(i+1);
 181     if (e2->lessThan(e1)) {
 182       _elements->at_put(i+1, e1);
 183       _elements->at_put(i,   e2);
 184     }
 185   }
 186 
 187   recache();
 188 }
 189 
 190 // remove the element at index
 191 void GrowableCache::remove (int index) {
 192   GrowableElement *e = _elements->at(index);
 193   assert(e != NULL, "e != NULL");
 194   _elements->remove(e);
 195   delete e;
 196   recache();
 197 }
 198 
 199 // clear out all elements, release all heap space and
 200 // let our listener know that things have changed.
 201 void GrowableCache::clear() {
 202   int len = _elements->length();
 203   for (int i=0; i<len; i++) {
 204     delete _elements->at(i);
 205   }
 206   _elements->clear();
 207   recache();
 208 }
 209 
 210 void GrowableCache::oops_do(OopClosure* f) {
 211   int len = _elements->length();
 212   for (int i=0; i<len; i++) {
 213     GrowableElement *e = _elements->at(i);
 214     e->oops_do(f);
 215   }
 216 }
 217 
 218 void GrowableCache::metadata_do(void f(Metadata*)) {
 219   int len = _elements->length();
 220   for (int i=0; i<len; i++) {
 221     GrowableElement *e = _elements->at(i);
 222     e->metadata_do(f);
 223   }
 224 }
 225 
 226 void GrowableCache::gc_epilogue() {
 227   int len = _elements->length();
 228   for (int i=0; i<len; i++) {
 229     _cache[i] = _elements->at(i)->getCacheValue();
 230   }
 231 }
 232 
 233 //
 234 // class JvmtiBreakpoint
 235 //
 236 
 237 JvmtiBreakpoint::JvmtiBreakpoint() {
 238   _method = NULL;
 239   _bci    = 0;
 240   _class_holder = NULL;
 241 }
 242 
 243 JvmtiBreakpoint::JvmtiBreakpoint(Method* m_method, jlocation location) {
 244   _method        = m_method;
 245   _class_holder  = _method->method_holder()->klass_holder();
 246 #ifdef CHECK_UNHANDLED_OOPS
 247   // _class_holder can't be wrapped in a Handle, because JvmtiBreakpoints are
 248   // sometimes allocated on the heap.
 249   //
 250   // The code handling JvmtiBreakpoints allocated on the stack can't be
 251   // interrupted by a GC until _class_holder is reachable by the GC via the
 252   // oops_do method.
 253   Thread::current()->allow_unhandled_oop(&_class_holder);
 254 #endif // CHECK_UNHANDLED_OOPS
 255   assert(_method != NULL, "_method != NULL");
 256   _bci           = (int) location;
 257   assert(_bci >= 0, "_bci >= 0");
 258 }
 259 
 260 void JvmtiBreakpoint::copy(JvmtiBreakpoint& bp) {
 261   _method   = bp._method;
 262   _bci      = bp._bci;
 263   _class_holder = bp._class_holder;
 264 }
 265 
 266 bool JvmtiBreakpoint::lessThan(JvmtiBreakpoint& bp) {
 267   Unimplemented();
 268   return false;
 269 }
 270 
 271 bool JvmtiBreakpoint::equals(JvmtiBreakpoint& bp) {
 272   return _method   == bp._method
 273     &&   _bci      == bp._bci;
 274 }
 275 
 276 bool JvmtiBreakpoint::is_valid() {
 277   // class loader can be NULL
 278   return _method != NULL &&
 279          _bci >= 0;
 280 }
 281 
 282 address JvmtiBreakpoint::getBcp() const {
 283   return _method->bcp_from(_bci);
 284 }
 285 
 286 void JvmtiBreakpoint::each_method_version_do(method_action meth_act) {
 287   ((Method*)_method->*meth_act)(_bci);
 288 
 289   // add/remove breakpoint to/from versions of the method that are EMCP.
 290   Thread *thread = Thread::current();
 291   InstanceKlass* ik = _method->method_holder();
 292   Symbol* m_name = _method->name();
 293   Symbol* m_signature = _method->signature();
 294 
 295   // search previous versions if they exist
 296   for (InstanceKlass* pv_node = ik->previous_versions();
 297        pv_node != NULL;
 298        pv_node = pv_node->previous_versions()) {
 299     Array<Method*>* methods = pv_node->methods();
 300 
 301     for (int i = methods->length() - 1; i >= 0; i--) {
 302       Method* method = methods->at(i);
 303       // Only set breakpoints in running EMCP methods.
 304       if (method->is_running_emcp() &&
 305           method->name() == m_name &&
 306           method->signature() == m_signature) {
 307         ResourceMark rm;
 308         log_debug(redefine, class, breakpoint)
 309           ("%sing breakpoint in %s(%s)", meth_act == &Method::set_breakpoint ? "sett" : "clear",
 310            method->name()->as_C_string(), method->signature()->as_C_string());
 311         (method->*meth_act)(_bci);
 312         break;
 313       }
 314     }
 315   }
 316 }
 317 
 318 void JvmtiBreakpoint::set() {
 319   each_method_version_do(&Method::set_breakpoint);
 320 }
 321 
 322 void JvmtiBreakpoint::clear() {
 323   each_method_version_do(&Method::clear_breakpoint);
 324 }
 325 
 326 void JvmtiBreakpoint::print_on(outputStream* out) const {
 327 #ifndef PRODUCT
 328   ResourceMark rm;
 329   const char *class_name  = (_method == NULL) ? "NULL" : _method->klass_name()->as_C_string();
 330   const char *method_name = (_method == NULL) ? "NULL" : _method->name()->as_C_string();
 331   out->print("Breakpoint(%s,%s,%d,%p)", class_name, method_name, _bci, getBcp());
 332 #endif
 333 }
 334 
 335 
 336 //
 337 // class VM_ChangeBreakpoints
 338 //
 339 // Modify the Breakpoints data structure at a safepoint
 340 //
 341 
 342 void VM_ChangeBreakpoints::doit() {
 343   switch (_operation) {
 344   case SET_BREAKPOINT:
 345     _breakpoints->set_at_safepoint(*_bp);
 346     break;
 347   case CLEAR_BREAKPOINT:
 348     _breakpoints->clear_at_safepoint(*_bp);
 349     break;
 350   default:
 351     assert(false, "Unknown operation");
 352   }
 353 }
 354 
 355 void VM_ChangeBreakpoints::oops_do(OopClosure* f) {
 356   // The JvmtiBreakpoints in _breakpoints will be visited via
 357   // JvmtiExport::oops_do.
 358   if (_bp != NULL) {
 359     _bp->oops_do(f);
 360   }
 361 }
 362 
 363 void VM_ChangeBreakpoints::metadata_do(void f(Metadata*)) {
 364   // Walk metadata in breakpoints to keep from being deallocated with RedefineClasses
 365   if (_bp != NULL) {
 366     _bp->metadata_do(f);
 367   }
 368 }
 369 
 370 //
 371 // class JvmtiBreakpoints
 372 //
 373 // a JVMTI internal collection of JvmtiBreakpoint
 374 //
 375 
 376 JvmtiBreakpoints::JvmtiBreakpoints(void listener_fun(void *,address *)) {
 377   _bps.initialize(this,listener_fun);
 378 }
 379 
 380 JvmtiBreakpoints:: ~JvmtiBreakpoints() {}
 381 
 382 void  JvmtiBreakpoints::oops_do(OopClosure* f) {
 383   _bps.oops_do(f);
 384 }
 385 
 386 void  JvmtiBreakpoints::metadata_do(void f(Metadata*)) {
 387   _bps.metadata_do(f);
 388 }
 389 
 390 void JvmtiBreakpoints::gc_epilogue() {
 391   _bps.gc_epilogue();
 392 }
 393 
 394 void JvmtiBreakpoints::print() {
 395 #ifndef PRODUCT
 396   LogTarget(Trace, jvmti) log;
 397   LogStream log_stream(log);
 398 
 399   int n = _bps.length();
 400   for (int i=0; i<n; i++) {
 401     JvmtiBreakpoint& bp = _bps.at(i);
 402     log_stream.print("%d: ", i);
 403     bp.print_on(&log_stream);
 404     log_stream.cr();
 405   }
 406 #endif
 407 }
 408 
 409 
 410 void JvmtiBreakpoints::set_at_safepoint(JvmtiBreakpoint& bp) {
 411   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 412 
 413   int i = _bps.find(bp);
 414   if (i == -1) {
 415     _bps.append(bp);
 416     bp.set();
 417   }
 418 }
 419 
 420 void JvmtiBreakpoints::clear_at_safepoint(JvmtiBreakpoint& bp) {
 421   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint");
 422 
 423   int i = _bps.find(bp);
 424   if (i != -1) {
 425     _bps.remove(i);
 426     bp.clear();
 427   }
 428 }
 429 
 430 int JvmtiBreakpoints::length() { return _bps.length(); }
 431 
 432 int JvmtiBreakpoints::set(JvmtiBreakpoint& bp) {
 433   if ( _bps.find(bp) != -1) {
 434      return JVMTI_ERROR_DUPLICATE;
 435   }
 436   VM_ChangeBreakpoints set_breakpoint(VM_ChangeBreakpoints::SET_BREAKPOINT, &bp);
 437   VMThread::execute(&set_breakpoint);
 438   return JVMTI_ERROR_NONE;
 439 }
 440 
 441 int JvmtiBreakpoints::clear(JvmtiBreakpoint& bp) {
 442   if ( _bps.find(bp) == -1) {
 443      return JVMTI_ERROR_NOT_FOUND;
 444   }
 445 
 446   VM_ChangeBreakpoints clear_breakpoint(VM_ChangeBreakpoints::CLEAR_BREAKPOINT, &bp);
 447   VMThread::execute(&clear_breakpoint);
 448   return JVMTI_ERROR_NONE;
 449 }
 450 
 451 void JvmtiBreakpoints::clearall_in_class_at_safepoint(Klass* klass) {
 452   bool changed = true;
 453   // We are going to run thru the list of bkpts
 454   // and delete some.  This deletion probably alters
 455   // the list in some implementation defined way such
 456   // that when we delete entry i, the next entry might
 457   // no longer be at i+1.  To be safe, each time we delete
 458   // an entry, we'll just start again from the beginning.
 459   // We'll stop when we make a pass thru the whole list without
 460   // deleting anything.
 461   while (changed) {
 462     int len = _bps.length();
 463     changed = false;
 464     for (int i = 0; i < len; i++) {
 465       JvmtiBreakpoint& bp = _bps.at(i);
 466       if (bp.method()->method_holder() == klass) {
 467         bp.clear();
 468         _bps.remove(i);
 469         // This changed 'i' so we have to start over.
 470         changed = true;
 471         break;
 472       }
 473     }
 474   }
 475 }
 476 
 477 //
 478 // class JvmtiCurrentBreakpoints
 479 //
 480 
 481 JvmtiBreakpoints *JvmtiCurrentBreakpoints::_jvmti_breakpoints  = NULL;
 482 address *         JvmtiCurrentBreakpoints::_breakpoint_list    = NULL;
 483 
 484 
 485 JvmtiBreakpoints& JvmtiCurrentBreakpoints::get_jvmti_breakpoints() {
 486   if (_jvmti_breakpoints != NULL) return (*_jvmti_breakpoints);
 487   _jvmti_breakpoints = new JvmtiBreakpoints(listener_fun);
 488   assert(_jvmti_breakpoints != NULL, "_jvmti_breakpoints != NULL");
 489   return (*_jvmti_breakpoints);
 490 }
 491 
 492 void  JvmtiCurrentBreakpoints::listener_fun(void *this_obj, address *cache) {
 493   JvmtiBreakpoints *this_jvmti = (JvmtiBreakpoints *) this_obj;
 494   assert(this_jvmti != NULL, "this_jvmti != NULL");
 495 
 496   debug_only(int n = this_jvmti->length(););
 497   assert(cache[n] == NULL, "cache must be NULL terminated");
 498 
 499   set_breakpoint_list(cache);
 500 }
 501 
 502 
 503 void JvmtiCurrentBreakpoints::oops_do(OopClosure* f) {
 504   if (_jvmti_breakpoints != NULL) {
 505     _jvmti_breakpoints->oops_do(f);
 506   }
 507 }
 508 
 509 void JvmtiCurrentBreakpoints::metadata_do(void f(Metadata*)) {
 510   if (_jvmti_breakpoints != NULL) {
 511     _jvmti_breakpoints->metadata_do(f);
 512   }
 513 }
 514 
 515 void JvmtiCurrentBreakpoints::gc_epilogue() {
 516   if (_jvmti_breakpoints != NULL) {
 517     _jvmti_breakpoints->gc_epilogue();
 518   }
 519 }
 520 
 521 ///////////////////////////////////////////////////////////////
 522 //
 523 // class VM_GetOrSetLocal
 524 //
 525 
 526 // Constructor for non-object getter
 527 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, jint index, BasicType type)
 528   : _thread(thread)
 529   , _calling_thread(NULL)
 530   , _depth(depth)
 531   , _index(index)
 532   , _type(type)
 533   , _set(false)
 534   , _jvf(NULL)
 535   , _result(JVMTI_ERROR_NONE)
 536 {
 537 }
 538 
 539 // Constructor for object or non-object setter
 540 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, jint depth, jint index, BasicType type, jvalue value)
 541   : _thread(thread)
 542   , _calling_thread(NULL)
 543   , _depth(depth)
 544   , _index(index)
 545   , _type(type)
 546   , _value(value)
 547   , _set(true)
 548   , _jvf(NULL)
 549   , _result(JVMTI_ERROR_NONE)
 550 {
 551 }
 552 
 553 // Constructor for object getter
 554 VM_GetOrSetLocal::VM_GetOrSetLocal(JavaThread* thread, JavaThread* calling_thread, jint depth, int index)
 555   : _thread(thread)
 556   , _calling_thread(calling_thread)
 557   , _depth(depth)
 558   , _index(index)
 559   , _type(T_OBJECT)
 560   , _set(false)
 561   , _jvf(NULL)
 562   , _result(JVMTI_ERROR_NONE)
 563 {
 564 }
 565 
 566 vframe *VM_GetOrSetLocal::get_vframe() {
 567   if (!_thread->has_last_Java_frame()) {
 568     return NULL;
 569   }
 570   RegisterMap reg_map(_thread);
 571   vframe *vf = _thread->last_java_vframe(&reg_map);
 572   int d = 0;
 573   while ((vf != NULL) && (d < _depth)) {
 574     vf = vf->java_sender();
 575     d++;
 576   }
 577   return vf;
 578 }
 579 
 580 javaVFrame *VM_GetOrSetLocal::get_java_vframe() {
 581   vframe* vf = get_vframe();
 582   if (vf == NULL) {
 583     _result = JVMTI_ERROR_NO_MORE_FRAMES;
 584     return NULL;
 585   }
 586   javaVFrame *jvf = (javaVFrame*)vf;
 587 
 588   if (!vf->is_java_frame()) {
 589     _result = JVMTI_ERROR_OPAQUE_FRAME;
 590     return NULL;
 591   }
 592   return jvf;
 593 }
 594 
 595 // Check that the klass is assignable to a type with the given signature.
 596 // Another solution could be to use the function Klass::is_subtype_of(type).
 597 // But the type class can be forced to load/initialize eagerly in such a case.
 598 // This may cause unexpected consequences like CFLH or class-init JVMTI events.
 599 // It is better to avoid such a behavior.
 600 bool VM_GetOrSetLocal::is_assignable(const char* ty_sign, Klass* klass, Thread* thread) {
 601   assert(ty_sign != NULL, "type signature must not be NULL");
 602   assert(thread != NULL, "thread must not be NULL");
 603   assert(klass != NULL, "klass must not be NULL");
 604 
 605   int len = (int) strlen(ty_sign);
 606   if (ty_sign[0] == 'L' && ty_sign[len-1] == ';') { // Need pure class/interface name
 607     ty_sign++;
 608     len -= 2;
 609   }
 610   TempNewSymbol ty_sym = SymbolTable::new_symbol(ty_sign, len, thread);
 611   if (klass->name() == ty_sym) {
 612     return true;
 613   }
 614   // Compare primary supers
 615   int super_depth = klass->super_depth();
 616   int idx;
 617   for (idx = 0; idx < super_depth; idx++) {
 618     if (klass->primary_super_of_depth(idx)->name() == ty_sym) {
 619       return true;
 620     }
 621   }
 622   // Compare secondary supers
 623   Array<Klass*>* sec_supers = klass->secondary_supers();
 624   for (idx = 0; idx < sec_supers->length(); idx++) {
 625     if (((Klass*) sec_supers->at(idx))->name() == ty_sym) {
 626       return true;
 627     }
 628   }
 629   return false;
 630 }
 631 
 632 // Checks error conditions:
 633 //   JVMTI_ERROR_INVALID_SLOT
 634 //   JVMTI_ERROR_TYPE_MISMATCH
 635 // Returns: 'true' - everything is Ok, 'false' - error code
 636 
 637 bool VM_GetOrSetLocal::check_slot_type(javaVFrame* jvf) {
 638   Method* method_oop = jvf->method();
 639   if (!method_oop->has_localvariable_table()) {
 640     // Just to check index boundaries
 641     jint extra_slot = (_type == T_LONG || _type == T_DOUBLE) ? 1 : 0;
 642     if (_index < 0 || _index + extra_slot >= method_oop->max_locals()) {
 643       _result = JVMTI_ERROR_INVALID_SLOT;
 644       return false;
 645     }
 646     return true;
 647   }
 648 
 649   jint num_entries = method_oop->localvariable_table_length();
 650   if (num_entries == 0) {
 651     _result = JVMTI_ERROR_INVALID_SLOT;
 652     return false;       // There are no slots
 653   }
 654   int signature_idx = -1;
 655   int vf_bci = jvf->bci();
 656   LocalVariableTableElement* table = method_oop->localvariable_table_start();
 657   for (int i = 0; i < num_entries; i++) {
 658     int start_bci = table[i].start_bci;
 659     int end_bci = start_bci + table[i].length;
 660 
 661     // Here we assume that locations of LVT entries
 662     // with the same slot number cannot be overlapped
 663     if (_index == (jint) table[i].slot && start_bci <= vf_bci && vf_bci <= end_bci) {
 664       signature_idx = (int) table[i].descriptor_cp_index;
 665       break;
 666     }
 667   }
 668   if (signature_idx == -1) {
 669     _result = JVMTI_ERROR_INVALID_SLOT;
 670     return false;       // Incorrect slot index
 671   }
 672   Symbol*   sign_sym  = method_oop->constants()->symbol_at(signature_idx);
 673   const char* signature = (const char *) sign_sym->as_utf8();
 674   BasicType slot_type = char2type(signature[0]);
 675 
 676   switch (slot_type) {
 677   case T_BYTE:
 678   case T_SHORT:
 679   case T_CHAR:
 680   case T_BOOLEAN:
 681     slot_type = T_INT;
 682     break;
 683   case T_ARRAY:
 684     slot_type = T_OBJECT;
 685     break;
 686   default:
 687     break;
 688   };
 689   if (_type != slot_type) {
 690     _result = JVMTI_ERROR_TYPE_MISMATCH;
 691     return false;
 692   }
 693 
 694   jobject jobj = _value.l;
 695   if (_set && slot_type == T_OBJECT && jobj != NULL) { // NULL reference is allowed
 696     // Check that the jobject class matches the return type signature.
 697     JavaThread* cur_thread = JavaThread::current();
 698     HandleMark hm(cur_thread);
 699 
 700     Handle obj(cur_thread, JNIHandles::resolve_external_guard(jobj));
 701     NULL_CHECK(obj, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
 702     Klass* ob_k = obj->klass();
 703     NULL_CHECK(ob_k, (_result = JVMTI_ERROR_INVALID_OBJECT, false));
 704 
 705     if (!is_assignable(signature, ob_k, cur_thread)) {
 706       _result = JVMTI_ERROR_TYPE_MISMATCH;
 707       return false;
 708     }
 709   }
 710   return true;
 711 }
 712 
 713 static bool can_be_deoptimized(vframe* vf) {
 714   return (vf->is_compiled_frame() && vf->fr().can_be_deoptimized());
 715 }
 716 
 717 bool VM_GetOrSetLocal::doit_prologue() {
 718   _jvf = get_java_vframe();
 719   NULL_CHECK(_jvf, false);
 720 
 721   if (_jvf->method()->is_native()) {
 722     if (getting_receiver() && !_jvf->method()->is_static()) {
 723       return true;
 724     } else {
 725       _result = JVMTI_ERROR_OPAQUE_FRAME;
 726       return false;
 727     }
 728   }
 729 
 730   if (!check_slot_type(_jvf)) {
 731     return false;
 732   }
 733   return true;
 734 }
 735 
 736 void VM_GetOrSetLocal::doit() {
 737   InterpreterOopMap oop_mask;
 738   _jvf->method()->mask_for(_jvf->bci(), &oop_mask);
 739   if (oop_mask.is_dead(_index)) {
 740     // The local can be invalid and uninitialized in the scope of current bci
 741     _result = JVMTI_ERROR_INVALID_SLOT;
 742     return;
 743   }
 744   if (_set) {
 745     // Force deoptimization of frame if compiled because it's
 746     // possible the compiler emitted some locals as constant values,
 747     // meaning they are not mutable.
 748     if (can_be_deoptimized(_jvf)) {
 749 
 750       // Schedule deoptimization so that eventually the local
 751       // update will be written to an interpreter frame.
 752       Deoptimization::deoptimize_frame(_jvf->thread(), _jvf->fr().id());
 753 
 754       // Now store a new value for the local which will be applied
 755       // once deoptimization occurs. Note however that while this
 756       // write is deferred until deoptimization actually happens
 757       // can vframe created after this point will have its locals
 758       // reflecting this update so as far as anyone can see the
 759       // write has already taken place.
 760 
 761       // If we are updating an oop then get the oop from the handle
 762       // since the handle will be long gone by the time the deopt
 763       // happens. The oop stored in the deferred local will be
 764       // gc'd on its own.
 765       if (_type == T_OBJECT) {
 766         _value.l = (jobject) (JNIHandles::resolve_external_guard(_value.l));
 767       }
 768       // Re-read the vframe so we can see that it is deoptimized
 769       // [ Only need because of assert in update_local() ]
 770       _jvf = get_java_vframe();
 771       ((compiledVFrame*)_jvf)->update_local(_type, _index, _value);
 772       return;
 773     }
 774     StackValueCollection *locals = _jvf->locals();
 775     HandleMark hm;
 776 
 777     switch (_type) {
 778       case T_INT:    locals->set_int_at   (_index, _value.i); break;
 779       case T_LONG:   locals->set_long_at  (_index, _value.j); break;
 780       case T_FLOAT:  locals->set_float_at (_index, _value.f); break;
 781       case T_DOUBLE: locals->set_double_at(_index, _value.d); break;
 782       case T_OBJECT: {
 783         Handle ob_h(Thread::current(), JNIHandles::resolve_external_guard(_value.l));
 784         locals->set_obj_at (_index, ob_h);
 785         break;
 786       }
 787       default: ShouldNotReachHere();
 788     }
 789     _jvf->set_locals(locals);
 790   } else {
 791     if (_jvf->method()->is_native() && _jvf->is_compiled_frame()) {
 792       assert(getting_receiver(), "Can only get here when getting receiver");
 793       oop receiver = _jvf->fr().get_native_receiver();
 794       _value.l = JNIHandles::make_local(_calling_thread, receiver);
 795     } else {
 796       StackValueCollection *locals = _jvf->locals();
 797 
 798       if (locals->at(_index)->type() == T_CONFLICT) {
 799         memset(&_value, 0, sizeof(_value));
 800         _value.l = NULL;
 801         return;
 802       }
 803 
 804       switch (_type) {
 805         case T_INT:    _value.i = locals->int_at   (_index);   break;
 806         case T_LONG:   _value.j = locals->long_at  (_index);   break;
 807         case T_FLOAT:  _value.f = locals->float_at (_index);   break;
 808         case T_DOUBLE: _value.d = locals->double_at(_index);   break;
 809         case T_OBJECT: {
 810           // Wrap the oop to be returned in a local JNI handle since
 811           // oops_do() no longer applies after doit() is finished.
 812           oop obj = locals->obj_at(_index)();
 813           _value.l = JNIHandles::make_local(_calling_thread, obj);
 814           break;
 815         }
 816         default: ShouldNotReachHere();
 817       }
 818     }
 819   }
 820 }
 821 
 822 
 823 bool VM_GetOrSetLocal::allow_nested_vm_operations() const {
 824   return true; // May need to deoptimize
 825 }
 826 
 827 
 828 VM_GetReceiver::VM_GetReceiver(
 829     JavaThread* thread, JavaThread* caller_thread, jint depth)
 830     : VM_GetOrSetLocal(thread, caller_thread, depth, 0) {}
 831 
 832 /////////////////////////////////////////////////////////////////////////////////////////
 833 
 834 //
 835 // class JvmtiSuspendControl - see comments in jvmtiImpl.hpp
 836 //
 837 
 838 bool JvmtiSuspendControl::suspend(JavaThread *java_thread) {
 839   // external suspend should have caught suspending a thread twice
 840 
 841   // Immediate suspension required for JPDA back-end so JVMTI agent threads do
 842   // not deadlock due to later suspension on transitions while holding
 843   // raw monitors.  Passing true causes the immediate suspension.
 844   // java_suspend() will catch threads in the process of exiting
 845   // and will ignore them.
 846   java_thread->java_suspend();
 847 
 848   // It would be nice to have the following assertion in all the time,
 849   // but it is possible for a racing resume request to have resumed
 850   // this thread right after we suspended it. Temporarily enable this
 851   // assertion if you are chasing a different kind of bug.
 852   //
 853   // assert(java_lang_Thread::thread(java_thread->threadObj()) == NULL ||
 854   //   java_thread->is_being_ext_suspended(), "thread is not suspended");
 855 
 856   if (java_lang_Thread::thread(java_thread->threadObj()) == NULL) {
 857     // check again because we can get delayed in java_suspend():
 858     // the thread is in process of exiting.
 859     return false;
 860   }
 861 
 862   return true;
 863 }
 864 
 865 bool JvmtiSuspendControl::resume(JavaThread *java_thread) {
 866   // external suspend should have caught resuming a thread twice
 867   assert(java_thread->is_being_ext_suspended(), "thread should be suspended");
 868 
 869   // resume thread
 870   {
 871     // must always grab Threads_lock, see JVM_SuspendThread
 872     MutexLocker ml(Threads_lock);
 873     java_thread->java_resume();
 874   }
 875 
 876   return true;
 877 }
 878 
 879 
 880 void JvmtiSuspendControl::print() {
 881 #ifndef PRODUCT

 882   LogStreamHandle(Trace, jvmti) log_stream;
 883   log_stream.print("Suspended Threads: [");
 884   for (JavaThreadIteratorWithHandle jtiwh; JavaThread *thread = jtiwh.next(); ) {
 885 #ifdef JVMTI_TRACE
 886     const char *name   = JvmtiTrace::safe_get_thread_name(thread);
 887 #else
 888     const char *name   = "";
 889 #endif /*JVMTI_TRACE */
 890     log_stream.print("%s(%c ", name, thread->is_being_ext_suspended() ? 'S' : '_');
 891     if (!thread->has_last_Java_frame()) {
 892       log_stream.print("no stack");
 893     }
 894     log_stream.print(") ");
 895   }
 896   log_stream.print_cr("]");
 897 #endif
 898 }
 899 
 900 JvmtiDeferredEvent JvmtiDeferredEvent::compiled_method_load_event(
 901     nmethod* nm) {
 902   JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_COMPILED_METHOD_LOAD);
 903   event._event_data.compiled_method_load = nm;
 904   // Keep the nmethod alive until the ServiceThread can process
 905   // this deferred event.
 906   nmethodLocker::lock_nmethod(nm);
 907   return event;
 908 }
 909 
 910 JvmtiDeferredEvent JvmtiDeferredEvent::compiled_method_unload_event(
 911     nmethod* nm, jmethodID id, const void* code) {
 912   JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_COMPILED_METHOD_UNLOAD);
 913   event._event_data.compiled_method_unload.nm = nm;
 914   event._event_data.compiled_method_unload.method_id = id;
 915   event._event_data.compiled_method_unload.code_begin = code;
 916   // Keep the nmethod alive until the ServiceThread can process
 917   // this deferred event. This will keep the memory for the
 918   // generated code from being reused too early. We pass
 919   // zombie_ok == true here so that our nmethod that was just
 920   // made into a zombie can be locked.
 921   nmethodLocker::lock_nmethod(nm, true /* zombie_ok */);
 922   return event;
 923 }
 924 
 925 JvmtiDeferredEvent JvmtiDeferredEvent::dynamic_code_generated_event(
 926       const char* name, const void* code_begin, const void* code_end) {
 927   JvmtiDeferredEvent event = JvmtiDeferredEvent(TYPE_DYNAMIC_CODE_GENERATED);
 928   // Need to make a copy of the name since we don't know how long
 929   // the event poster will keep it around after we enqueue the
 930   // deferred event and return. strdup() failure is handled in
 931   // the post() routine below.
 932   event._event_data.dynamic_code_generated.name = os::strdup(name);
 933   event._event_data.dynamic_code_generated.code_begin = code_begin;
 934   event._event_data.dynamic_code_generated.code_end = code_end;
 935   return event;
 936 }
 937 
 938 void JvmtiDeferredEvent::post() {
 939   assert(ServiceThread::is_service_thread(Thread::current()),
 940          "Service thread must post enqueued events");
 941   switch(_type) {
 942     case TYPE_COMPILED_METHOD_LOAD: {
 943       nmethod* nm = _event_data.compiled_method_load;
 944       JvmtiExport::post_compiled_method_load(nm);
 945       // done with the deferred event so unlock the nmethod
 946       nmethodLocker::unlock_nmethod(nm);
 947       break;
 948     }
 949     case TYPE_COMPILED_METHOD_UNLOAD: {
 950       nmethod* nm = _event_data.compiled_method_unload.nm;
 951       JvmtiExport::post_compiled_method_unload(
 952         _event_data.compiled_method_unload.method_id,
 953         _event_data.compiled_method_unload.code_begin);
 954       // done with the deferred event so unlock the nmethod
 955       nmethodLocker::unlock_nmethod(nm);
 956       break;
 957     }
 958     case TYPE_DYNAMIC_CODE_GENERATED: {
 959       JvmtiExport::post_dynamic_code_generated_internal(
 960         // if strdup failed give the event a default name
 961         (_event_data.dynamic_code_generated.name == NULL)
 962           ? "unknown_code" : _event_data.dynamic_code_generated.name,
 963         _event_data.dynamic_code_generated.code_begin,
 964         _event_data.dynamic_code_generated.code_end);
 965       if (_event_data.dynamic_code_generated.name != NULL) {
 966         // release our copy
 967         os::free((void *)_event_data.dynamic_code_generated.name);
 968       }
 969       break;
 970     }
 971     default:
 972       ShouldNotReachHere();
 973   }
 974 }
 975 
 976 JvmtiDeferredEventQueue::QueueNode* JvmtiDeferredEventQueue::_queue_tail = NULL;
 977 JvmtiDeferredEventQueue::QueueNode* JvmtiDeferredEventQueue::_queue_head = NULL;
 978 
 979 bool JvmtiDeferredEventQueue::has_events() {
 980   assert(Service_lock->owned_by_self(), "Must own Service_lock");
 981   return _queue_head != NULL;
 982 }
 983 
 984 void JvmtiDeferredEventQueue::enqueue(const JvmtiDeferredEvent& event) {
 985   assert(Service_lock->owned_by_self(), "Must own Service_lock");
 986 
 987   // Events get added to the end of the queue (and are pulled off the front).
 988   QueueNode* node = new QueueNode(event);
 989   if (_queue_tail == NULL) {
 990     _queue_tail = _queue_head = node;
 991   } else {
 992     assert(_queue_tail->next() == NULL, "Must be the last element in the list");
 993     _queue_tail->set_next(node);
 994     _queue_tail = node;
 995   }
 996 
 997   Service_lock->notify_all();
 998   assert((_queue_head == NULL) == (_queue_tail == NULL),
 999          "Inconsistent queue markers");
1000 }
1001 
1002 JvmtiDeferredEvent JvmtiDeferredEventQueue::dequeue() {
1003   assert(Service_lock->owned_by_self(), "Must own Service_lock");
1004 
1005   assert(_queue_head != NULL, "Nothing to dequeue");
1006 
1007   if (_queue_head == NULL) {
1008     // Just in case this happens in product; it shouldn't but let's not crash
1009     return JvmtiDeferredEvent();
1010   }
1011 
1012   QueueNode* node = _queue_head;
1013   _queue_head = _queue_head->next();
1014   if (_queue_head == NULL) {
1015     _queue_tail = NULL;
1016   }
1017 
1018   assert((_queue_head == NULL) == (_queue_tail == NULL),
1019          "Inconsistent queue markers");
1020 
1021   JvmtiDeferredEvent event = node->event();
1022   delete node;
1023   return event;
1024 }
--- EOF ---