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