1 /*
   2  * Copyright (c) 2003, 2023, 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/javaClasses.inline.hpp"
  27 #include "classfile/moduleEntry.hpp"
  28 #include "classfile/vmClasses.hpp"
  29 #include "classfile/vmSymbols.hpp"
  30 #include "code/nmethod.hpp"
  31 #include "code/pcDesc.hpp"
  32 #include "code/scopeDesc.hpp"
  33 #include "gc/shared/oopStorageSet.hpp"
  34 #include "interpreter/interpreter.hpp"
  35 #include "jvmtifiles/jvmtiEnv.hpp"
  36 #include "logging/log.hpp"
  37 #include "logging/logStream.hpp"
  38 #include "memory/allocation.inline.hpp"
  39 #include "memory/resourceArea.hpp"
  40 #include "memory/universe.hpp"
  41 #include "oops/klass.inline.hpp"
  42 #include "oops/objArrayKlass.hpp"
  43 #include "oops/objArrayOop.hpp"
  44 #include "oops/oop.inline.hpp"
  45 #include "oops/oopHandle.inline.hpp"
  46 #include "prims/jvmtiAgentList.hpp"
  47 #include "prims/jvmtiCodeBlobEvents.hpp"
  48 #include "prims/jvmtiEventController.hpp"
  49 #include "prims/jvmtiEventController.inline.hpp"
  50 #include "prims/jvmtiExport.hpp"
  51 #include "prims/jvmtiImpl.hpp"
  52 #include "prims/jvmtiManageCapabilities.hpp"
  53 #include "prims/jvmtiRawMonitor.hpp"
  54 #include "prims/jvmtiRedefineClasses.hpp"
  55 #include "prims/jvmtiTagMap.hpp"
  56 #include "prims/jvmtiThreadState.inline.hpp"
  57 #include "runtime/arguments.hpp"
  58 #include "runtime/fieldDescriptor.inline.hpp"
  59 #include "runtime/handles.inline.hpp"
  60 #include "runtime/interfaceSupport.inline.hpp"
  61 #include "runtime/javaCalls.hpp"
  62 #include "runtime/javaThread.hpp"
  63 #include "runtime/jniHandles.inline.hpp"
  64 #include "runtime/keepStackGCProcessed.hpp"
  65 #include "runtime/objectMonitor.hpp"
  66 #include "runtime/objectMonitor.inline.hpp"
  67 #include "runtime/os.hpp"
  68 #include "runtime/osThread.hpp"
  69 #include "runtime/safepointVerifiers.hpp"
  70 #include "runtime/serviceThread.hpp"
  71 #include "runtime/threads.hpp"
  72 #include "runtime/threadSMR.hpp"
  73 #include "runtime/vframe.inline.hpp"
  74 #include "runtime/vm_version.hpp"
  75 #include "utilities/macros.hpp"
  76 
  77 #ifdef JVMTI_TRACE
  78 #define EVT_TRACE(evt,out) if ((JvmtiTrace::event_trace_flags(evt) & JvmtiTrace::SHOW_EVENT_SENT) != 0) { SafeResourceMark rm; log_trace(jvmti) out; }
  79 #define EVT_TRIG_TRACE(evt,out) if ((JvmtiTrace::event_trace_flags(evt) & JvmtiTrace::SHOW_EVENT_TRIGGER) != 0) { SafeResourceMark rm; log_trace(jvmti) out; }
  80 #else
  81 #define EVT_TRIG_TRACE(evt,out)
  82 #define EVT_TRACE(evt,out)
  83 #endif
  84 
  85 ///////////////////////////////////////////////////////////////
  86 //
  87 // JvmtiEventTransition
  88 //
  89 // TO DO --
  90 //  more handle purging
  91 
  92 // Use this for JavaThreads and state is  _thread_in_vm.
  93 class JvmtiJavaThreadEventTransition : StackObj {
  94 private:
  95   ResourceMark _rm;
  96   ThreadToNativeFromVM _transition;
  97   HandleMark _hm;
  98 
  99 public:
 100   JvmtiJavaThreadEventTransition(JavaThread *thread) :
 101     _rm(),
 102     _transition(thread),
 103     _hm(thread)  {};
 104 };
 105 
 106 // For JavaThreads which are not in _thread_in_vm state
 107 // and other system threads use this.
 108 class JvmtiThreadEventTransition : StackObj {
 109 private:
 110   ResourceMark _rm;
 111   HandleMark _hm;
 112   JavaThreadState _saved_state;
 113   JavaThread *_jthread;
 114 
 115 public:
 116   JvmtiThreadEventTransition(Thread *thread) : _rm(), _hm(thread) {
 117     if (thread->is_Java_thread()) {
 118        _jthread = JavaThread::cast(thread);
 119        _saved_state = _jthread->thread_state();
 120        if (_saved_state == _thread_in_Java) {
 121          ThreadStateTransition::transition_from_java(_jthread, _thread_in_native);
 122        } else {
 123          ThreadStateTransition::transition_from_vm(_jthread, _thread_in_native);
 124        }
 125     } else {
 126       _jthread = nullptr;
 127     }
 128   }
 129 
 130   ~JvmtiThreadEventTransition() {
 131     if (_jthread != nullptr)
 132       ThreadStateTransition::transition_from_native(_jthread, _saved_state);
 133   }
 134 };
 135 
 136 
 137 ///////////////////////////////////////////////////////////////
 138 //
 139 // JvmtiEventMark
 140 //
 141 
 142 class JvmtiEventMark : public StackObj {
 143 private:
 144   JavaThread *_thread;
 145   JNIEnv* _jni_env;
 146   JvmtiThreadState::ExceptionState _saved_exception_state;
 147 
 148 public:
 149   JvmtiEventMark(JavaThread *thread) :  _thread(thread),
 150                                         _jni_env(thread->jni_environment()),
 151                                         _saved_exception_state(JvmtiThreadState::ES_CLEARED) {
 152     JvmtiThreadState *state = thread->jvmti_thread_state();
 153     // we are before an event.
 154     // Save current jvmti thread exception state.
 155     if (state != nullptr) {
 156       _saved_exception_state = state->get_exception_state();
 157     }
 158 
 159     thread->push_jni_handle_block();
 160     assert(thread == JavaThread::current(), "thread must be current!");
 161     thread->frame_anchor()->make_walkable();
 162   };
 163 
 164   ~JvmtiEventMark() {
 165     _thread->pop_jni_handle_block();
 166 
 167     JvmtiThreadState* state = _thread->jvmti_thread_state();
 168     // we are continuing after an event.
 169     if (state != nullptr) {
 170       // Restore the jvmti thread exception state.
 171       state->restore_exception_state(_saved_exception_state);
 172     }
 173   }
 174 
 175   jobject to_jobject(oop obj) { return JNIHandles::make_local(_thread,obj); }
 176 
 177   jclass to_jclass(Klass* klass) { return (klass == nullptr ? nullptr : (jclass)to_jobject(klass->java_mirror())); }
 178 
 179   jmethodID to_jmethodID(const methodHandle& method) { return method->jmethod_id(); }
 180 
 181   JNIEnv* jni_env() { return _jni_env; }
 182 };
 183 
 184 class JvmtiThreadEventMark : public JvmtiEventMark {
 185 private:
 186   jobject _jthread;
 187 
 188 public:
 189   JvmtiThreadEventMark(JavaThread *thread) :
 190     JvmtiEventMark(thread) {
 191     _jthread = to_jobject(thread->threadObj());
 192   };
 193  jthread jni_thread() { return (jthread)_jthread; }
 194 };
 195 
 196 class JvmtiVirtualThreadEventMark : public JvmtiEventMark {
 197 private:
 198   jobject _jthread;
 199 
 200 public:
 201   JvmtiVirtualThreadEventMark(JavaThread *thread) :
 202     JvmtiEventMark(thread) {
 203     assert(thread->vthread() != nullptr || thread->threadObj() == nullptr, "sanity check");
 204     _jthread = to_jobject(thread->vthread());
 205   };
 206   jthread jni_thread() { return (jthread)_jthread; }
 207 };
 208 
 209 class JvmtiClassEventMark : public JvmtiVirtualThreadEventMark {
 210 private:
 211   jclass _jc;
 212 
 213 public:
 214   JvmtiClassEventMark(JavaThread *thread, Klass* klass) :
 215     JvmtiVirtualThreadEventMark(thread) {
 216     _jc = to_jclass(klass);
 217   };
 218   jclass jni_class() { return _jc; }
 219 };
 220 
 221 class JvmtiMethodEventMark : public JvmtiVirtualThreadEventMark {
 222 private:
 223   jmethodID _mid;
 224 
 225 public:
 226   JvmtiMethodEventMark(JavaThread *thread, const methodHandle& method) :
 227     JvmtiVirtualThreadEventMark(thread),
 228     _mid(to_jmethodID(method)) {};
 229   jmethodID jni_methodID() { return _mid; }
 230 };
 231 
 232 class JvmtiLocationEventMark : public JvmtiMethodEventMark {
 233 private:
 234   jlocation _loc;
 235 
 236 public:
 237   JvmtiLocationEventMark(JavaThread *thread, const methodHandle& method, address location) :
 238     JvmtiMethodEventMark(thread, method),
 239     _loc(location - method->code_base()) {};
 240   jlocation location() { return _loc; }
 241 };
 242 
 243 class JvmtiExceptionEventMark : public JvmtiLocationEventMark {
 244 private:
 245   jobject _exc;
 246 
 247 public:
 248   JvmtiExceptionEventMark(JavaThread *thread, const methodHandle& method, address location, Handle exception) :
 249     JvmtiLocationEventMark(thread, method, location),
 250     _exc(to_jobject(exception())) {};
 251   jobject exception() { return _exc; }
 252 };
 253 
 254 class JvmtiClassFileLoadEventMark : public JvmtiThreadEventMark {
 255 private:
 256   const char *_class_name;
 257   jobject _jloader;
 258   jobject _protection_domain;
 259   jclass  _class_being_redefined;
 260 
 261 public:
 262   JvmtiClassFileLoadEventMark(JavaThread *thread, Symbol* name,
 263      Handle class_loader, Handle prot_domain, Klass* class_being_redefined) : JvmtiThreadEventMark(thread) {
 264       _class_name = name != nullptr? name->as_utf8() : nullptr;
 265       _jloader = (jobject)to_jobject(class_loader());
 266       _protection_domain = (jobject)to_jobject(prot_domain());
 267       if (class_being_redefined == nullptr) {
 268         _class_being_redefined = nullptr;
 269       } else {
 270         _class_being_redefined = (jclass)to_jclass(class_being_redefined);
 271       }
 272   };
 273   const char *class_name() {
 274     return _class_name;
 275   }
 276   jobject jloader() {
 277     return _jloader;
 278   }
 279   jobject protection_domain() {
 280     return _protection_domain;
 281   }
 282   jclass class_being_redefined() {
 283     return _class_being_redefined;
 284   }
 285 };
 286 
 287 //////////////////////////////////////////////////////////////////////////////
 288 
 289 int               JvmtiExport::_field_access_count                        = 0;
 290 int               JvmtiExport::_field_modification_count                  = 0;
 291 
 292 bool              JvmtiExport::_can_access_local_variables                = false;
 293 bool              JvmtiExport::_can_hotswap_or_post_breakpoint            = false;
 294 bool              JvmtiExport::_can_modify_any_class                      = false;
 295 bool              JvmtiExport::_can_walk_any_space                        = false;
 296 
 297 uint64_t          JvmtiExport::_redefinition_count                        = 0;
 298 bool              JvmtiExport::_all_dependencies_are_recorded             = false;
 299 
 300 //
 301 // field access management
 302 //
 303 
 304 // interpreter generator needs the address of the counter
 305 address JvmtiExport::get_field_access_count_addr() {
 306   // We don't grab a lock because we don't want to
 307   // serialize field access between all threads. This means that a
 308   // thread on another processor can see the wrong count value and
 309   // may either miss making a needed call into post_field_access()
 310   // or will make an unneeded call into post_field_access(). We pay
 311   // this price to avoid slowing down the VM when we aren't watching
 312   // field accesses.
 313   // Other access/mutation safe by virtue of being in VM state.
 314   return (address)(&_field_access_count);
 315 }
 316 
 317 //
 318 // field modification management
 319 //
 320 
 321 // interpreter generator needs the address of the counter
 322 address JvmtiExport::get_field_modification_count_addr() {
 323   // We don't grab a lock because we don't
 324   // want to serialize field modification between all threads. This
 325   // means that a thread on another processor can see the wrong
 326   // count value and may either miss making a needed call into
 327   // post_field_modification() or will make an unneeded call into
 328   // post_field_modification(). We pay this price to avoid slowing
 329   // down the VM when we aren't watching field modifications.
 330   // Other access/mutation safe by virtue of being in VM state.
 331   return (address)(&_field_modification_count);
 332 }
 333 
 334 
 335 ///////////////////////////////////////////////////////////////
 336 // Functions needed by java.lang.instrument for starting up javaagent.
 337 ///////////////////////////////////////////////////////////////
 338 
 339 jint
 340 JvmtiExport::get_jvmti_interface(JavaVM *jvm, void **penv, jint version) {
 341   // The JVMTI_VERSION_INTERFACE_JVMTI part of the version number
 342   // has already been validated in JNI GetEnv().
 343   int major, minor, micro;
 344 
 345   // micro version doesn't matter here (yet?)
 346   decode_version_values(version, &major, &minor, &micro);
 347   switch (major) {
 348     case 1:
 349       switch (minor) {
 350         case 0:  // version 1.0.<micro> is recognized
 351         case 1:  // version 1.1.<micro> is recognized
 352         case 2:  // version 1.2.<micro> is recognized
 353           break;
 354 
 355         default:
 356           return JNI_EVERSION;  // unsupported minor version number
 357       }
 358       break;
 359     case 9:
 360       switch (minor) {
 361         case 0:  // version 9.0.<micro> is recognized
 362           break;
 363         default:
 364           return JNI_EVERSION;  // unsupported minor version number
 365       }
 366       break;
 367     case 11:
 368       switch (minor) {
 369         case 0:  // version 11.0.<micro> is recognized
 370           break;
 371         default:
 372           return JNI_EVERSION;  // unsupported minor version number
 373       }
 374       break;
 375     default:
 376       // Starting from 13 we do not care about minor version anymore
 377       if (major < 13 || major > VM_Version::vm_major_version()) {
 378         return JNI_EVERSION;  // unsupported major version number
 379       }
 380   }
 381 
 382   if (JvmtiEnv::get_phase() == JVMTI_PHASE_LIVE) {
 383     JavaThread* current_thread = JavaThread::current();
 384     // transition code: native to VM
 385     ThreadInVMfromNative __tiv(current_thread);
 386     VM_ENTRY_BASE(jvmtiEnv*, JvmtiExport::get_jvmti_interface, current_thread)
 387     debug_only(VMNativeEntryWrapper __vew;)
 388 
 389     JvmtiEnv *jvmti_env = JvmtiEnv::create_a_jvmti(version);
 390     *penv = jvmti_env->jvmti_external();  // actual type is jvmtiEnv* -- not to be confused with JvmtiEnv*
 391 
 392     if (Continuations::enabled()) {
 393       // Virtual threads support for agents loaded into running VM.
 394       // There is a performance impact when VTMS transitions are enabled.
 395       if (!JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
 396         JvmtiEnvBase::enable_virtual_threads_notify_jvmti();
 397       }
 398     }
 399     return JNI_OK;
 400 
 401   } else if (JvmtiEnv::get_phase() == JVMTI_PHASE_ONLOAD) {
 402     // not live, no thread to transition
 403     JvmtiEnv *jvmti_env = JvmtiEnv::create_a_jvmti(version);
 404     *penv = jvmti_env->jvmti_external();  // actual type is jvmtiEnv* -- not to be confused with JvmtiEnv*
 405 
 406     if (Continuations::enabled()) {
 407       // Virtual threads support for agents loaded at startup.
 408       // There is a performance impact when VTMS transitions are enabled.
 409       JvmtiVTMSTransitionDisabler::set_VTMS_notify_jvmti_events(true);
 410     }
 411     return JNI_OK;
 412 
 413   } else {
 414     // Called at the wrong time
 415     *penv = nullptr;
 416     return JNI_EDETACHED;
 417   }
 418 }
 419 
 420 JvmtiThreadState*
 421 JvmtiExport::get_jvmti_thread_state(JavaThread *thread) {
 422   assert(thread == JavaThread::current(), "must be current thread");
 423   if (thread->is_vthread_mounted() && thread->jvmti_thread_state() == nullptr) {
 424     JvmtiEventController::thread_started(thread);
 425   }
 426   return thread->jvmti_thread_state();
 427 }
 428 
 429 void
 430 JvmtiExport::add_default_read_edges(Handle h_module, TRAPS) {
 431   if (!Universe::is_module_initialized()) {
 432     return; // extra safety
 433   }
 434   assert(!h_module.is_null(), "module should always be set");
 435 
 436   // Invoke the transformedByAgent method
 437   JavaValue result(T_VOID);
 438   JavaCalls::call_static(&result,
 439                          vmClasses::module_Modules_klass(),
 440                          vmSymbols::transformedByAgent_name(),
 441                          vmSymbols::transformedByAgent_signature(),
 442                          h_module,
 443                          THREAD);
 444 
 445   if (HAS_PENDING_EXCEPTION) {
 446     LogTarget(Trace, jvmti) log;
 447     LogStream log_stream(log);
 448     java_lang_Throwable::print(PENDING_EXCEPTION, &log_stream);
 449     log_stream.cr();
 450     CLEAR_PENDING_EXCEPTION;
 451     return;
 452   }
 453 }
 454 
 455 jvmtiError
 456 JvmtiExport::add_module_reads(Handle module, Handle to_module, TRAPS) {
 457   if (!Universe::is_module_initialized()) {
 458     return JVMTI_ERROR_NONE; // extra safety
 459   }
 460   assert(!module.is_null(), "module should always be set");
 461   assert(!to_module.is_null(), "to_module should always be set");
 462 
 463   // Invoke the addReads method
 464   JavaValue result(T_VOID);
 465   JavaCalls::call_static(&result,
 466                          vmClasses::module_Modules_klass(),
 467                          vmSymbols::addReads_name(),
 468                          vmSymbols::addReads_signature(),
 469                          module,
 470                          to_module,
 471                          THREAD);
 472 
 473   if (HAS_PENDING_EXCEPTION) {
 474     LogTarget(Trace, jvmti) log;
 475     LogStream log_stream(log);
 476     java_lang_Throwable::print(PENDING_EXCEPTION, &log_stream);
 477     log_stream.cr();
 478     CLEAR_PENDING_EXCEPTION;
 479     return JVMTI_ERROR_INTERNAL;
 480   }
 481   return JVMTI_ERROR_NONE;
 482 }
 483 
 484 jvmtiError
 485 JvmtiExport::add_module_exports(Handle module, Handle pkg_name, Handle to_module, TRAPS) {
 486   if (!Universe::is_module_initialized()) {
 487     return JVMTI_ERROR_NONE; // extra safety
 488   }
 489   assert(!module.is_null(), "module should always be set");
 490   assert(!to_module.is_null(), "to_module should always be set");
 491   assert(!pkg_name.is_null(), "pkg_name should always be set");
 492 
 493   // Invoke the addExports method
 494   JavaValue result(T_VOID);
 495   JavaCalls::call_static(&result,
 496                          vmClasses::module_Modules_klass(),
 497                          vmSymbols::addExports_name(),
 498                          vmSymbols::addExports_signature(),
 499                          module,
 500                          pkg_name,
 501                          to_module,
 502                          THREAD);
 503 
 504   if (HAS_PENDING_EXCEPTION) {
 505     Symbol* ex_name = PENDING_EXCEPTION->klass()->name();
 506     LogTarget(Trace, jvmti) log;
 507     LogStream log_stream(log);
 508     java_lang_Throwable::print(PENDING_EXCEPTION, &log_stream);
 509     log_stream.cr();
 510     CLEAR_PENDING_EXCEPTION;
 511     if (ex_name == vmSymbols::java_lang_IllegalArgumentException()) {
 512       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 513     }
 514     return JVMTI_ERROR_INTERNAL;
 515   }
 516   return JVMTI_ERROR_NONE;
 517 }
 518 
 519 jvmtiError
 520 JvmtiExport::add_module_opens(Handle module, Handle pkg_name, Handle to_module, TRAPS) {
 521   if (!Universe::is_module_initialized()) {
 522     return JVMTI_ERROR_NONE; // extra safety
 523   }
 524   assert(!module.is_null(), "module should always be set");
 525   assert(!to_module.is_null(), "to_module should always be set");
 526   assert(!pkg_name.is_null(), "pkg_name should always be set");
 527 
 528   // Invoke the addOpens method
 529   JavaValue result(T_VOID);
 530   JavaCalls::call_static(&result,
 531                          vmClasses::module_Modules_klass(),
 532                          vmSymbols::addOpens_name(),
 533                          vmSymbols::addExports_signature(),
 534                          module,
 535                          pkg_name,
 536                          to_module,
 537                          THREAD);
 538 
 539   if (HAS_PENDING_EXCEPTION) {
 540     Symbol* ex_name = PENDING_EXCEPTION->klass()->name();
 541     LogTarget(Trace, jvmti) log;
 542     LogStream log_stream(log);
 543     java_lang_Throwable::print(PENDING_EXCEPTION, &log_stream);
 544     log_stream.cr();
 545     CLEAR_PENDING_EXCEPTION;
 546     if (ex_name == vmSymbols::java_lang_IllegalArgumentException()) {
 547       return JVMTI_ERROR_ILLEGAL_ARGUMENT;
 548     }
 549     return JVMTI_ERROR_INTERNAL;
 550   }
 551   return JVMTI_ERROR_NONE;
 552 }
 553 
 554 jvmtiError
 555 JvmtiExport::add_module_uses(Handle module, Handle service, TRAPS) {
 556   if (!Universe::is_module_initialized()) {
 557     return JVMTI_ERROR_NONE; // extra safety
 558   }
 559   assert(!module.is_null(), "module should always be set");
 560   assert(!service.is_null(), "service should always be set");
 561 
 562   // Invoke the addUses method
 563   JavaValue result(T_VOID);
 564   JavaCalls::call_static(&result,
 565                          vmClasses::module_Modules_klass(),
 566                          vmSymbols::addUses_name(),
 567                          vmSymbols::addUses_signature(),
 568                          module,
 569                          service,
 570                          THREAD);
 571 
 572   if (HAS_PENDING_EXCEPTION) {
 573     LogTarget(Trace, jvmti) log;
 574     LogStream log_stream(log);
 575     java_lang_Throwable::print(PENDING_EXCEPTION, &log_stream);
 576     log_stream.cr();
 577     CLEAR_PENDING_EXCEPTION;
 578     return JVMTI_ERROR_INTERNAL;
 579   }
 580   return JVMTI_ERROR_NONE;
 581 }
 582 
 583 jvmtiError
 584 JvmtiExport::add_module_provides(Handle module, Handle service, Handle impl_class, TRAPS) {
 585   if (!Universe::is_module_initialized()) {
 586     return JVMTI_ERROR_NONE; // extra safety
 587   }
 588   assert(!module.is_null(), "module should always be set");
 589   assert(!service.is_null(), "service should always be set");
 590   assert(!impl_class.is_null(), "impl_class should always be set");
 591 
 592   // Invoke the addProvides method
 593   JavaValue result(T_VOID);
 594   JavaCalls::call_static(&result,
 595                          vmClasses::module_Modules_klass(),
 596                          vmSymbols::addProvides_name(),
 597                          vmSymbols::addProvides_signature(),
 598                          module,
 599                          service,
 600                          impl_class,
 601                          THREAD);
 602 
 603   if (HAS_PENDING_EXCEPTION) {
 604     LogTarget(Trace, jvmti) log;
 605     LogStream log_stream(log);
 606     java_lang_Throwable::print(PENDING_EXCEPTION, &log_stream);
 607     log_stream.cr();
 608     CLEAR_PENDING_EXCEPTION;
 609     return JVMTI_ERROR_INTERNAL;
 610   }
 611   return JVMTI_ERROR_NONE;
 612 }
 613 
 614 void
 615 JvmtiExport::decode_version_values(jint version, int * major, int * minor,
 616                                    int * micro) {
 617   *major = (version & JVMTI_VERSION_MASK_MAJOR) >> JVMTI_VERSION_SHIFT_MAJOR;
 618   *minor = (version & JVMTI_VERSION_MASK_MINOR) >> JVMTI_VERSION_SHIFT_MINOR;
 619   *micro = (version & JVMTI_VERSION_MASK_MICRO) >> JVMTI_VERSION_SHIFT_MICRO;
 620 }
 621 
 622 void JvmtiExport::enter_primordial_phase() {
 623   JvmtiEnvBase::set_phase(JVMTI_PHASE_PRIMORDIAL);
 624 }
 625 
 626 void JvmtiExport::enter_early_start_phase() {
 627   set_early_vmstart_recorded(true);
 628 }
 629 
 630 void JvmtiExport::enter_start_phase() {
 631   JvmtiEnvBase::set_phase(JVMTI_PHASE_START);
 632 }
 633 
 634 void JvmtiExport::enter_onload_phase() {
 635   JvmtiEnvBase::set_phase(JVMTI_PHASE_ONLOAD);
 636 }
 637 
 638 void JvmtiExport::enter_live_phase() {
 639   JvmtiEnvBase::set_phase(JVMTI_PHASE_LIVE);
 640 }
 641 
 642 //
 643 // JVMTI events that the VM posts to the debugger and also startup agent
 644 // and call the agent's premain() for java.lang.instrument.
 645 //
 646 
 647 void JvmtiExport::post_early_vm_start() {
 648   EVT_TRIG_TRACE(JVMTI_EVENT_VM_START, ("Trg Early VM start event triggered" ));
 649 
 650   // can now enable some events
 651   JvmtiEventController::vm_start();
 652 
 653   JvmtiEnvIterator it;
 654   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
 655     // Only early vmstart envs post early VMStart event
 656     if (env->early_vmstart_env() && env->is_enabled(JVMTI_EVENT_VM_START)) {
 657       EVT_TRACE(JVMTI_EVENT_VM_START, ("Evt Early VM start event sent" ));
 658       JavaThread *thread  = JavaThread::current();
 659       JvmtiThreadEventMark jem(thread);
 660       JvmtiJavaThreadEventTransition jet(thread);
 661       jvmtiEventVMStart callback = env->callbacks()->VMStart;
 662       if (callback != nullptr) {
 663         (*callback)(env->jvmti_external(), jem.jni_env());
 664       }
 665     }
 666   }
 667 }
 668 
 669 void JvmtiExport::post_vm_start() {
 670   EVT_TRIG_TRACE(JVMTI_EVENT_VM_START, ("Trg VM start event triggered" ));
 671 
 672   // can now enable some events
 673   JvmtiEventController::vm_start();
 674 
 675   JvmtiEnvIterator it;
 676   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
 677     // Early vmstart envs do not post normal VMStart event
 678     if (!env->early_vmstart_env() && env->is_enabled(JVMTI_EVENT_VM_START)) {
 679       EVT_TRACE(JVMTI_EVENT_VM_START, ("Evt VM start event sent" ));
 680 
 681       JavaThread *thread  = JavaThread::current();
 682       JvmtiThreadEventMark jem(thread);
 683       JvmtiJavaThreadEventTransition jet(thread);
 684       jvmtiEventVMStart callback = env->callbacks()->VMStart;
 685       if (callback != nullptr) {
 686         (*callback)(env->jvmti_external(), jem.jni_env());
 687       }
 688     }
 689   }
 690 }
 691 
 692 static OopStorage* _jvmti_oop_storage = nullptr;
 693 static OopStorage* _weak_tag_storage = nullptr;
 694 
 695 OopStorage* JvmtiExport::jvmti_oop_storage() {
 696   assert(_jvmti_oop_storage != nullptr, "not yet initialized");
 697   return _jvmti_oop_storage;
 698 }
 699 
 700 OopStorage* JvmtiExport::weak_tag_storage() {
 701   assert(_weak_tag_storage != nullptr, "not yet initialized");
 702   return _weak_tag_storage;
 703 }
 704 
 705 void JvmtiExport::initialize_oop_storage() {
 706   // OopStorage needs to be created early in startup and unconditionally
 707   // because of OopStorageSet static array indices.
 708   _jvmti_oop_storage = OopStorageSet::create_strong("JVMTI OopStorage", mtServiceability);
 709   _weak_tag_storage  = OopStorageSet::create_weak("JVMTI Tag Weak OopStorage", mtServiceability);
 710   _weak_tag_storage->register_num_dead_callback(&JvmtiTagMap::gc_notification);
 711 }
 712 
 713 // Lookup an agent from an JvmtiEnv. Return agent only if it is not yet initialized.
 714 // An agent can create multiple JvmtiEnvs, but for agent initialization, we are only interested in the initial one.
 715 static JvmtiAgent* lookup_uninitialized_agent(JvmtiEnv* env, void* callback) {
 716   JvmtiAgent* const agent = JvmtiAgentList::lookup(env, callback);
 717   return agent == nullptr || agent->is_initialized() ? nullptr : agent;
 718 }
 719 
 720 void JvmtiExport::post_vm_initialized() {
 721   EVT_TRIG_TRACE(JVMTI_EVENT_VM_INIT, ("Trg VM init event triggered" ));
 722 
 723   // can now enable events
 724   JvmtiEventController::vm_init();
 725 
 726   JvmtiEnvIterator it;
 727   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
 728     if (env->is_enabled(JVMTI_EVENT_VM_INIT)) {
 729       EVT_TRACE(JVMTI_EVENT_VM_INIT, ("Evt VM init event sent" ));
 730 
 731       JavaThread *thread  = JavaThread::current();
 732       JvmtiThreadEventMark jem(thread);
 733       JvmtiJavaThreadEventTransition jet(thread);
 734       jvmtiEventVMInit callback = env->callbacks()->VMInit;
 735       if (callback != nullptr) {
 736         // We map the JvmtiEnv to its Agent to measure when and for how long
 737         // it took to initialize so that JFR can report this information.
 738         JvmtiAgent* const agent = lookup_uninitialized_agent(env, reinterpret_cast<void*>(callback));
 739         if (agent != nullptr) {
 740           agent->initialization_begin();
 741         }
 742         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread());
 743         if (agent != nullptr) {
 744           agent->initialization_end();
 745         }
 746       }
 747     }
 748   }
 749 
 750   // Agents are initialized as part of posting the VMInit event above.
 751   // For -Xrun agents and agents with no VMInit callback, we explicitly ensure they are also initialized.
 752   // JVM_OnLoad and Agent_OnLoad callouts are performed too early for the proper timestamp logic.
 753   JvmtiAgentList::initialize();
 754 }
 755 
 756 void JvmtiExport::post_vm_death() {
 757   EVT_TRIG_TRACE(JVMTI_EVENT_VM_DEATH, ("Trg VM death event triggered" ));
 758 
 759   JvmtiTagMap::flush_all_object_free_events();
 760 
 761   JvmtiEnvIterator it;
 762   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
 763     if (env->is_enabled(JVMTI_EVENT_VM_DEATH)) {
 764       EVT_TRACE(JVMTI_EVENT_VM_DEATH, ("Evt VM death event sent" ));
 765 
 766       JavaThread *thread  = JavaThread::current();
 767       JvmtiEventMark jem(thread);
 768       JvmtiJavaThreadEventTransition jet(thread);
 769       jvmtiEventVMDeath callback = env->callbacks()->VMDeath;
 770       if (callback != nullptr) {
 771         (*callback)(env->jvmti_external(), jem.jni_env());
 772       }
 773     }
 774   }
 775 
 776   JvmtiEnvBase::set_phase(JVMTI_PHASE_DEAD);
 777   JvmtiEventController::vm_death();
 778 }
 779 
 780 char**
 781 JvmtiExport::get_all_native_method_prefixes(int* count_ptr) {
 782   // Have to grab JVMTI thread state lock to be sure environment doesn't
 783   // go away while we iterate them.  No locks during VM bring-up.
 784   if (Threads::number_of_threads() == 0 || SafepointSynchronize::is_at_safepoint()) {
 785     return JvmtiEnvBase::get_all_native_method_prefixes(count_ptr);
 786   } else {
 787     MutexLocker mu(JvmtiThreadState_lock);
 788     return JvmtiEnvBase::get_all_native_method_prefixes(count_ptr);
 789   }
 790 }
 791 
 792 // Convert an external thread reference to a JavaThread found on the
 793 // specified ThreadsList. The ThreadsListHandle in the caller "protects"
 794 // the returned JavaThread *.
 795 //
 796 // If thread_oop_p is not null, then the caller wants to use the oop
 797 // after this call so the oop is returned. On success, *jt_pp is set
 798 // to the converted JavaThread * and JVMTI_ERROR_NONE is returned.
 799 // On error, returns various JVMTI_ERROR_* values.
 800 //
 801 jvmtiError
 802 JvmtiExport::cv_external_thread_to_JavaThread(ThreadsList * t_list,
 803                                               jthread thread,
 804                                               JavaThread ** jt_pp,
 805                                               oop * thread_oop_p) {
 806   assert(t_list != nullptr, "must have a ThreadsList");
 807   assert(jt_pp != nullptr, "must have a return JavaThread pointer");
 808   // thread_oop_p is optional so no assert()
 809 
 810   if (thread_oop_p != nullptr) {
 811     *thread_oop_p = nullptr;
 812   }
 813 
 814   oop thread_oop = JNIHandles::resolve_external_guard(thread);
 815   if (thread_oop == nullptr) {
 816     // null jthread, GC'ed jthread or a bad JNI handle.
 817     return JVMTI_ERROR_INVALID_THREAD;
 818   }
 819   // Looks like an oop at this point.
 820 
 821   if (!thread_oop->is_a(vmClasses::Thread_klass())) {
 822     // The oop is not a java.lang.Thread.
 823     return JVMTI_ERROR_INVALID_THREAD;
 824   }
 825   // Looks like a java.lang.Thread oop at this point.
 826 
 827   if (thread_oop_p != nullptr) {
 828     // Return the oop to the caller; the caller may still want
 829     // the oop even if this function returns an error.
 830     *thread_oop_p = thread_oop;
 831   }
 832 
 833   JavaThread * java_thread = java_lang_Thread::thread(thread_oop);
 834   if (java_thread == nullptr) {
 835     if (java_lang_VirtualThread::is_instance(thread_oop)) {
 836       return JVMTI_ERROR_INVALID_THREAD;
 837     }
 838     // The java.lang.Thread does not contain a JavaThread * so it has
 839     // not yet run or it has died.
 840     return JVMTI_ERROR_THREAD_NOT_ALIVE;
 841   }
 842   // Looks like a live JavaThread at this point.
 843 
 844   if (!t_list->includes(java_thread)) {
 845     // Not on the JavaThreads list so it is not alive.
 846     return JVMTI_ERROR_THREAD_NOT_ALIVE;
 847   }
 848 
 849   // Return a live JavaThread that is "protected" by the
 850   // ThreadsListHandle in the caller.
 851   *jt_pp = java_thread;
 852 
 853   return JVMTI_ERROR_NONE;
 854 }
 855 
 856 // Convert an oop to a JavaThread found on the specified ThreadsList.
 857 // The ThreadsListHandle in the caller "protects" the returned
 858 // JavaThread *.
 859 //
 860 // On success, *jt_pp is set to the converted JavaThread * and
 861 // JVMTI_ERROR_NONE is returned. On error, returns various
 862 // JVMTI_ERROR_* values.
 863 //
 864 jvmtiError
 865 JvmtiExport::cv_oop_to_JavaThread(ThreadsList * t_list, oop thread_oop,
 866                                   JavaThread ** jt_pp) {
 867   assert(t_list != nullptr, "must have a ThreadsList");
 868   assert(thread_oop != nullptr, "must have an oop");
 869   assert(jt_pp != nullptr, "must have a return JavaThread pointer");
 870 
 871   if (!thread_oop->is_a(vmClasses::Thread_klass())) {
 872     // The oop is not a java.lang.Thread.
 873     return JVMTI_ERROR_INVALID_THREAD;
 874   }
 875   // Looks like a java.lang.Thread oop at this point.
 876 
 877   JavaThread * java_thread = java_lang_Thread::thread(thread_oop);
 878   if (java_thread == nullptr) {
 879     // The java.lang.Thread does not contain a JavaThread * so it has
 880     // not yet run or it has died.
 881     return JVMTI_ERROR_THREAD_NOT_ALIVE;
 882   }
 883   // Looks like a live JavaThread at this point.
 884 
 885   if (!t_list->includes(java_thread)) {
 886     // Not on the JavaThreads list so it is not alive.
 887     return JVMTI_ERROR_THREAD_NOT_ALIVE;
 888   }
 889 
 890   // Return a live JavaThread that is "protected" by the
 891   // ThreadsListHandle in the caller.
 892   *jt_pp = java_thread;
 893 
 894   return JVMTI_ERROR_NONE;
 895 }
 896 
 897 class JvmtiClassFileLoadHookPoster : public StackObj {
 898  private:
 899   Symbol*            _h_name;
 900   Handle               _class_loader;
 901   Handle               _h_protection_domain;
 902   unsigned char **     _data_ptr;
 903   unsigned char **     _end_ptr;
 904   JavaThread *         _thread;
 905   jint                 _curr_len;
 906   unsigned char *      _curr_data;
 907   JvmtiEnv *           _curr_env;
 908   JvmtiCachedClassFileData ** _cached_class_file_ptr;
 909   JvmtiThreadState *   _state;
 910   Klass*               _class_being_redefined;
 911   JvmtiClassLoadKind   _load_kind;
 912   bool                 _has_been_modified;
 913 
 914  public:
 915   inline JvmtiClassFileLoadHookPoster(Symbol* h_name, Handle class_loader,
 916                                       Handle h_protection_domain,
 917                                       unsigned char **data_ptr, unsigned char **end_ptr,
 918                                       JvmtiCachedClassFileData **cache_ptr) {
 919     _h_name = h_name;
 920     _class_loader = class_loader;
 921     _h_protection_domain = h_protection_domain;
 922     _data_ptr = data_ptr;
 923     _end_ptr = end_ptr;
 924     _thread = JavaThread::current();
 925     _curr_len = pointer_delta_as_int(*end_ptr, *data_ptr);
 926     _curr_data = *data_ptr;
 927     _curr_env = nullptr;
 928     _cached_class_file_ptr = cache_ptr;
 929     _has_been_modified = false;
 930 
 931     assert(!_thread->is_in_any_VTMS_transition(), "CFLH events are not allowed in any VTMS transition");
 932     _state = JvmtiExport::get_jvmti_thread_state(_thread);
 933     if (_state != nullptr) {
 934       _class_being_redefined = _state->get_class_being_redefined();
 935       _load_kind = _state->get_class_load_kind();
 936       Klass* klass = (_class_being_redefined == nullptr) ? nullptr : _class_being_redefined;
 937       if (_load_kind != jvmti_class_load_kind_load && klass != nullptr) {
 938         ModuleEntry* module_entry = InstanceKlass::cast(klass)->module();
 939         assert(module_entry != nullptr, "module_entry should always be set");
 940         if (module_entry->is_named() &&
 941             module_entry->module() != nullptr &&
 942             !module_entry->has_default_read_edges()) {
 943           if (!module_entry->set_has_default_read_edges()) {
 944             // We won a potential race.
 945             // Add read edges to the unnamed modules of the bootstrap and app class loaders
 946             Handle class_module(_thread, module_entry->module()); // Obtain j.l.r.Module
 947             JvmtiExport::add_default_read_edges(class_module, _thread);
 948           }
 949         }
 950       }
 951       // Clear class_being_redefined flag here. The action
 952       // from agent handler could generate a new class file load
 953       // hook event and if it is not cleared the new event generated
 954       // from regular class file load could have this stale redefined
 955       // class handle info.
 956       _state->clear_class_being_redefined();
 957     } else {
 958       // redefine and retransform will always set the thread state
 959       _class_being_redefined = nullptr;
 960       _load_kind = jvmti_class_load_kind_load;
 961     }
 962   }
 963 
 964   void post() {
 965     post_all_envs();
 966     copy_modified_data();
 967   }
 968 
 969   bool has_been_modified() { return _has_been_modified; }
 970 
 971  private:
 972   void post_all_envs() {
 973     if (_load_kind != jvmti_class_load_kind_retransform) {
 974       // for class load and redefine,
 975       // call the non-retransformable agents
 976       JvmtiEnvIterator it;
 977       for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
 978         if (!env->is_retransformable() && env->is_enabled(JVMTI_EVENT_CLASS_FILE_LOAD_HOOK)) {
 979           // non-retransformable agents cannot retransform back,
 980           // so no need to cache the original class file bytes
 981           post_to_env(env, false);
 982         }
 983       }
 984     }
 985     JvmtiEnvIterator it;
 986     for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
 987       // retransformable agents get all events
 988       if (env->is_retransformable() && env->is_enabled(JVMTI_EVENT_CLASS_FILE_LOAD_HOOK)) {
 989         // retransformable agents need to cache the original class file
 990         // bytes if changes are made via the ClassFileLoadHook
 991         post_to_env(env, true);
 992       }
 993     }
 994   }
 995 
 996   void post_to_env(JvmtiEnv* env, bool caching_needed) {
 997     if (env->phase() == JVMTI_PHASE_PRIMORDIAL && !env->early_class_hook_env()) {
 998       return;
 999     }
1000     unsigned char *new_data = nullptr;
1001     jint new_len = 0;
1002     JvmtiClassFileLoadEventMark jem(_thread, _h_name, _class_loader,
1003                                     _h_protection_domain,
1004                                     _class_being_redefined);
1005     JvmtiJavaThreadEventTransition jet(_thread);
1006     jvmtiEventClassFileLoadHook callback = env->callbacks()->ClassFileLoadHook;
1007     if (callback != nullptr) {
1008       (*callback)(env->jvmti_external(), jem.jni_env(),
1009                   jem.class_being_redefined(),
1010                   jem.jloader(), jem.class_name(),
1011                   jem.protection_domain(),
1012                   _curr_len, _curr_data,
1013                   &new_len, &new_data);
1014     }
1015     if (new_data != nullptr) {
1016       // this agent has modified class data.
1017       _has_been_modified = true;
1018       if (caching_needed && *_cached_class_file_ptr == nullptr) {
1019         // data has been changed by the new retransformable agent
1020         // and it hasn't already been cached, cache it
1021         JvmtiCachedClassFileData *p;
1022         p = (JvmtiCachedClassFileData *)os::malloc(
1023           offset_of(JvmtiCachedClassFileData, data) + _curr_len, mtInternal);
1024         if (p == nullptr) {
1025           vm_exit_out_of_memory(offset_of(JvmtiCachedClassFileData, data) + _curr_len,
1026             OOM_MALLOC_ERROR,
1027             "unable to allocate cached copy of original class bytes");
1028         }
1029         p->length = _curr_len;
1030         memcpy(p->data, _curr_data, _curr_len);
1031         *_cached_class_file_ptr = p;
1032       }
1033 
1034       if (_curr_data != *_data_ptr) {
1035         // curr_data is previous agent modified class data.
1036         // And this has been changed by the new agent so
1037         // we can delete it now.
1038         _curr_env->Deallocate(_curr_data);
1039       }
1040 
1041       // Class file data has changed by the current agent.
1042       _curr_data = new_data;
1043       _curr_len = new_len;
1044       // Save the current agent env we need this to deallocate the
1045       // memory allocated by this agent.
1046       _curr_env = env;
1047     }
1048   }
1049 
1050   void copy_modified_data() {
1051     // if one of the agent has modified class file data.
1052     // Copy modified class data to new resources array.
1053     if (_curr_data != *_data_ptr) {
1054       *_data_ptr = NEW_RESOURCE_ARRAY(u1, _curr_len);
1055       memcpy(*_data_ptr, _curr_data, _curr_len);
1056       *_end_ptr = *_data_ptr + _curr_len;
1057       _curr_env->Deallocate(_curr_data);
1058     }
1059   }
1060 };
1061 
1062 bool JvmtiExport::is_early_phase() {
1063   return JvmtiEnvBase::get_phase() <= JVMTI_PHASE_PRIMORDIAL;
1064 }
1065 
1066 bool JvmtiExport::has_early_class_hook_env() {
1067   JvmtiEnvIterator it;
1068   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
1069     if (env->early_class_hook_env()) {
1070       return true;
1071     }
1072   }
1073   return false;
1074 }
1075 
1076 bool JvmtiExport::_should_post_class_file_load_hook = false;
1077 
1078 // This flag is read by C2 during VM internal objects allocation
1079 int JvmtiExport::_should_notify_object_alloc = 0;
1080 
1081 // this entry is for class file load hook on class load, redefine and retransform
1082 bool JvmtiExport::post_class_file_load_hook(Symbol* h_name,
1083                                             Handle class_loader,
1084                                             Handle h_protection_domain,
1085                                             unsigned char **data_ptr,
1086                                             unsigned char **end_ptr,
1087                                             JvmtiCachedClassFileData **cache_ptr) {
1088   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1089     return false;
1090   }
1091   if (JavaThread::current()->is_in_tmp_VTMS_transition()) {
1092     return false; // skip CFLH events in tmp VTMS transition
1093   }
1094 
1095   JvmtiClassFileLoadHookPoster poster(h_name, class_loader,
1096                                       h_protection_domain,
1097                                       data_ptr, end_ptr,
1098                                       cache_ptr);
1099   poster.post();
1100   return poster.has_been_modified();
1101 }
1102 
1103 void JvmtiExport::report_unsupported(bool on) {
1104   // If any JVMTI service is turned on, we need to exit before native code
1105   // tries to access nonexistent services.
1106   if (on) {
1107     vm_exit_during_initialization("Java Kernel does not support JVMTI.");
1108   }
1109 }
1110 
1111 
1112 static inline Klass* oop_to_klass(oop obj) {
1113   Klass* k = obj->klass();
1114 
1115   // if the object is a java.lang.Class then return the java mirror
1116   if (k == vmClasses::Class_klass()) {
1117     if (!java_lang_Class::is_primitive(obj)) {
1118       k = java_lang_Class::as_Klass(obj);
1119       assert(k != nullptr, "class for non-primitive mirror must exist");
1120     }
1121   }
1122   return k;
1123 }
1124 
1125 class JvmtiObjectAllocEventMark : public JvmtiClassEventMark  {
1126  private:
1127    jobject _jobj;
1128    jlong    _size;
1129  public:
1130    JvmtiObjectAllocEventMark(JavaThread *thread, oop obj) : JvmtiClassEventMark(thread, oop_to_klass(obj)) {
1131      _jobj = (jobject)to_jobject(obj);
1132      _size = obj->size() * wordSize;
1133    };
1134    jobject jni_jobject() { return _jobj; }
1135    jlong size() { return _size; }
1136 };
1137 
1138 class JvmtiCompiledMethodLoadEventMark : public JvmtiMethodEventMark {
1139  private:
1140   jint _code_size;
1141   const void *_code_data;
1142   jint _map_length;
1143   jvmtiAddrLocationMap *_map;
1144   const void *_compile_info;
1145  public:
1146   JvmtiCompiledMethodLoadEventMark(JavaThread *thread, nmethod *nm, void* compile_info_ptr = nullptr)
1147           : JvmtiMethodEventMark(thread,methodHandle(thread, nm->method())) {
1148     _code_data = nm->code_begin();
1149     _code_size = nm->code_size();
1150     _compile_info = compile_info_ptr; // Set void pointer of compiledMethodLoad Event. Default value is null.
1151     JvmtiCodeBlobEvents::build_jvmti_addr_location_map(nm, &_map, &_map_length);
1152   }
1153   ~JvmtiCompiledMethodLoadEventMark() {
1154      FREE_C_HEAP_ARRAY(jvmtiAddrLocationMap, _map);
1155   }
1156 
1157   jint code_size() { return _code_size; }
1158   const void *code_data() { return _code_data; }
1159   jint map_length() { return _map_length; }
1160   const jvmtiAddrLocationMap* map() { return _map; }
1161   const void *compile_info() { return _compile_info; }
1162 };
1163 
1164 
1165 
1166 class JvmtiMonitorEventMark : public JvmtiVirtualThreadEventMark {
1167 private:
1168   jobject _jobj;
1169 public:
1170   JvmtiMonitorEventMark(JavaThread *thread, oop object)
1171           : JvmtiVirtualThreadEventMark(thread){
1172      _jobj = to_jobject(object);
1173   }
1174   jobject jni_object() { return _jobj; }
1175 };
1176 
1177 ///////////////////////////////////////////////////////////////
1178 //
1179 // pending CompiledMethodUnload support
1180 //
1181 
1182 void JvmtiExport::post_compiled_method_unload(
1183        jmethodID method, const void *code_begin) {
1184   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1185     return;
1186   }
1187   JavaThread* thread = JavaThread::current();
1188   EVT_TRIG_TRACE(JVMTI_EVENT_COMPILED_METHOD_UNLOAD,
1189                  ("[%s] method compile unload event triggered",
1190                   JvmtiTrace::safe_get_thread_name(thread)));
1191 
1192   // post the event for each environment that has this event enabled.
1193   JvmtiEnvIterator it;
1194   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
1195     if (env->is_enabled(JVMTI_EVENT_COMPILED_METHOD_UNLOAD)) {
1196       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1197         continue;
1198       }
1199       EVT_TRACE(JVMTI_EVENT_COMPILED_METHOD_UNLOAD,
1200                 ("[%s] class compile method unload event sent jmethodID " PTR_FORMAT,
1201                  JvmtiTrace::safe_get_thread_name(thread), p2i(method)));
1202 
1203       ResourceMark rm(thread);
1204 
1205       JvmtiEventMark jem(thread);
1206       JvmtiJavaThreadEventTransition jet(thread);
1207       jvmtiEventCompiledMethodUnload callback = env->callbacks()->CompiledMethodUnload;
1208       if (callback != nullptr) {
1209         (*callback)(env->jvmti_external(), method, code_begin);
1210       }
1211     }
1212   }
1213 }
1214 
1215 ///////////////////////////////////////////////////////////////
1216 //
1217 // JvmtiExport
1218 //
1219 
1220 void JvmtiExport::post_raw_breakpoint(JavaThread *thread, Method* method, address location) {
1221   HandleMark hm(thread);
1222   methodHandle mh(thread, method);
1223 
1224   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1225   if (state == nullptr) {
1226     return;
1227   }
1228   if (thread->is_in_any_VTMS_transition()) {
1229     return; // no events should be posted if thread is in any VTMS transition
1230   }
1231 
1232   EVT_TRIG_TRACE(JVMTI_EVENT_BREAKPOINT, ("[%s] Trg Breakpoint triggered",
1233                       JvmtiTrace::safe_get_thread_name(thread)));
1234   JvmtiEnvThreadStateIterator it(state);
1235   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1236     ets->compare_and_set_current_location(mh(), location, JVMTI_EVENT_BREAKPOINT);
1237     if (!ets->breakpoint_posted() && ets->is_enabled(JVMTI_EVENT_BREAKPOINT)) {
1238       ThreadState old_os_state = thread->osthread()->get_state();
1239       thread->osthread()->set_state(BREAKPOINTED);
1240       EVT_TRACE(JVMTI_EVENT_BREAKPOINT, ("[%s] Evt Breakpoint sent %s.%s @ " INTX_FORMAT,
1241                      JvmtiTrace::safe_get_thread_name(thread),
1242                      (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1243                      (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
1244                      location - mh()->code_base() ));
1245 
1246       JvmtiEnv *env = ets->get_env();
1247       JvmtiLocationEventMark jem(thread, mh, location);
1248       JvmtiJavaThreadEventTransition jet(thread);
1249       jvmtiEventBreakpoint callback = env->callbacks()->Breakpoint;
1250       if (callback != nullptr) {
1251         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
1252                     jem.jni_methodID(), jem.location());
1253       }
1254 
1255       ets->set_breakpoint_posted();
1256       thread->osthread()->set_state(old_os_state);
1257     }
1258   }
1259 }
1260 
1261 //////////////////////////////////////////////////////////////////////////////
1262 
1263 bool              JvmtiExport::_can_get_source_debug_extension            = false;
1264 bool              JvmtiExport::_can_maintain_original_method_order        = false;
1265 bool              JvmtiExport::_can_post_interpreter_events               = false;
1266 bool              JvmtiExport::_can_post_on_exceptions                    = false;
1267 bool              JvmtiExport::_can_post_breakpoint                       = false;
1268 bool              JvmtiExport::_can_post_field_access                     = false;
1269 bool              JvmtiExport::_can_post_field_modification               = false;
1270 bool              JvmtiExport::_can_post_method_entry                     = false;
1271 bool              JvmtiExport::_can_post_method_exit                      = false;
1272 bool              JvmtiExport::_can_post_frame_pop                        = false;
1273 bool              JvmtiExport::_can_pop_frame                             = false;
1274 bool              JvmtiExport::_can_force_early_return                    = false;
1275 bool              JvmtiExport::_can_support_virtual_threads               = false;
1276 bool              JvmtiExport::_can_get_owned_monitor_info                = false;
1277 
1278 bool              JvmtiExport::_early_vmstart_recorded                    = false;
1279 
1280 bool              JvmtiExport::_should_post_single_step                   = false;
1281 bool              JvmtiExport::_should_post_field_access                  = false;
1282 bool              JvmtiExport::_should_post_field_modification            = false;
1283 bool              JvmtiExport::_should_post_class_load                    = false;
1284 bool              JvmtiExport::_should_post_class_prepare                 = false;
1285 bool              JvmtiExport::_should_post_class_unload                  = false;
1286 bool              JvmtiExport::_should_post_thread_life                   = false;
1287 bool              JvmtiExport::_should_clean_up_heap_objects              = false;
1288 bool              JvmtiExport::_should_post_native_method_bind            = false;
1289 bool              JvmtiExport::_should_post_dynamic_code_generated        = false;
1290 bool              JvmtiExport::_should_post_data_dump                     = false;
1291 bool              JvmtiExport::_should_post_compiled_method_load          = false;
1292 bool              JvmtiExport::_should_post_compiled_method_unload        = false;
1293 bool              JvmtiExport::_should_post_monitor_contended_enter       = false;
1294 bool              JvmtiExport::_should_post_monitor_contended_entered     = false;
1295 bool              JvmtiExport::_should_post_monitor_wait                  = false;
1296 bool              JvmtiExport::_should_post_monitor_waited                = false;
1297 bool              JvmtiExport::_should_post_garbage_collection_start      = false;
1298 bool              JvmtiExport::_should_post_garbage_collection_finish     = false;
1299 bool              JvmtiExport::_should_post_object_free                   = false;
1300 bool              JvmtiExport::_should_post_resource_exhausted            = false;
1301 bool              JvmtiExport::_should_post_vm_object_alloc               = false;
1302 bool              JvmtiExport::_should_post_sampled_object_alloc          = false;
1303 bool              JvmtiExport::_should_post_on_exceptions                 = false;
1304 bool              JvmtiExport::_should_post_vthread_start                 = false;
1305 bool              JvmtiExport::_should_post_vthread_end                   = false;
1306 bool              JvmtiExport::_should_post_vthread_mount                 = false;
1307 bool              JvmtiExport::_should_post_vthread_unmount               = false;
1308 
1309 ////////////////////////////////////////////////////////////////////////////////////////////////
1310 
1311 
1312 //
1313 // JVMTI single step management
1314 //
1315 void JvmtiExport::at_single_stepping_point(JavaThread *thread, Method* method, address location) {
1316   assert(JvmtiExport::should_post_single_step(), "must be single stepping");
1317 
1318   HandleMark hm(thread);
1319   methodHandle mh(thread, method);
1320 
1321   // update information about current location and post a step event
1322   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1323   if (state == nullptr) {
1324     return;
1325   }
1326   EVT_TRIG_TRACE(JVMTI_EVENT_SINGLE_STEP, ("[%s] Trg Single Step triggered",
1327                       JvmtiTrace::safe_get_thread_name(thread)));
1328   if (!state->hide_single_stepping()) {
1329     if (state->is_pending_step_for_popframe()) {
1330       state->process_pending_step_for_popframe();
1331     }
1332     if (state->is_pending_step_for_earlyret()) {
1333       state->process_pending_step_for_earlyret();
1334     }
1335     JvmtiExport::post_single_step(thread, mh(), location);
1336   }
1337 }
1338 
1339 
1340 void JvmtiExport::expose_single_stepping(JavaThread *thread) {
1341   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1342   if (state != nullptr) {
1343     state->clear_hide_single_stepping();
1344   }
1345 }
1346 
1347 
1348 bool JvmtiExport::hide_single_stepping(JavaThread *thread) {
1349   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1350   if (state != nullptr && state->is_enabled(JVMTI_EVENT_SINGLE_STEP)) {
1351     state->set_hide_single_stepping();
1352     return true;
1353   } else {
1354     return false;
1355   }
1356 }
1357 
1358 void JvmtiExport::post_class_load(JavaThread *thread, Klass* klass) {
1359   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1360     return;
1361   }
1362   HandleMark hm(thread);
1363 
1364   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1365   if (state == nullptr) {
1366     return;
1367   }
1368   if (thread->is_in_tmp_VTMS_transition()) {
1369     return; // skip ClassLoad events in tmp VTMS transition
1370   }
1371   assert(!thread->is_in_any_VTMS_transition(), "class load events are not allowed in any VTMS transition");
1372 
1373   EVT_TRIG_TRACE(JVMTI_EVENT_CLASS_LOAD, ("[%s] Trg Class Load triggered",
1374                       JvmtiTrace::safe_get_thread_name(thread)));
1375   JvmtiEnvThreadStateIterator it(state);
1376   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1377     if (ets->is_enabled(JVMTI_EVENT_CLASS_LOAD)) {
1378       JvmtiEnv *env = ets->get_env();
1379       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1380         continue;
1381       }
1382       EVT_TRACE(JVMTI_EVENT_CLASS_LOAD, ("[%s] Evt Class Load sent %s",
1383                                          JvmtiTrace::safe_get_thread_name(thread),
1384                                          klass==nullptr? "null" : klass->external_name() ));
1385       JvmtiClassEventMark jem(thread, klass);
1386       JvmtiJavaThreadEventTransition jet(thread);
1387       jvmtiEventClassLoad callback = env->callbacks()->ClassLoad;
1388       if (callback != nullptr) {
1389         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(), jem.jni_class());
1390       }
1391     }
1392   }
1393 }
1394 
1395 
1396 void JvmtiExport::post_class_prepare(JavaThread *thread, Klass* klass) {
1397   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1398     return;
1399   }
1400   HandleMark hm(thread);
1401 
1402   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1403   if (state == nullptr) {
1404     return;
1405   }
1406   if (thread->is_in_tmp_VTMS_transition()) {
1407     return; // skip ClassPrepare events in tmp VTMS transition
1408   }
1409   assert(!thread->is_in_any_VTMS_transition(), "class prepare events are not allowed in any VTMS transition");
1410 
1411   EVT_TRIG_TRACE(JVMTI_EVENT_CLASS_PREPARE, ("[%s] Trg Class Prepare triggered",
1412                       JvmtiTrace::safe_get_thread_name(thread)));
1413   JvmtiEnvThreadStateIterator it(state);
1414   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1415     if (ets->is_enabled(JVMTI_EVENT_CLASS_PREPARE)) {
1416       JvmtiEnv *env = ets->get_env();
1417       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1418         continue;
1419       }
1420       EVT_TRACE(JVMTI_EVENT_CLASS_PREPARE, ("[%s] Evt Class Prepare sent %s",
1421                                             JvmtiTrace::safe_get_thread_name(thread),
1422                                             klass==nullptr? "null" : klass->external_name() ));
1423       JvmtiClassEventMark jem(thread, klass);
1424       JvmtiJavaThreadEventTransition jet(thread);
1425       jvmtiEventClassPrepare callback = env->callbacks()->ClassPrepare;
1426       if (callback != nullptr) {
1427         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(), jem.jni_class());
1428       }
1429     }
1430   }
1431 }
1432 
1433 void JvmtiExport::post_class_unload(Klass* klass) {
1434   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1435     return;
1436   }
1437 
1438   // postings to the service thread so that it can perform them in a safe
1439   // context and in-order.
1440   ResourceMark rm;
1441   // JvmtiDeferredEvent copies the string.
1442   JvmtiDeferredEvent event = JvmtiDeferredEvent::class_unload_event(klass->name()->as_C_string());
1443   ServiceThread::enqueue_deferred_event(&event);
1444 }
1445 
1446 
1447 void JvmtiExport::post_class_unload_internal(const char* name) {
1448   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1449     return;
1450   }
1451   assert(Thread::current()->is_service_thread(), "must be called from ServiceThread");
1452   JavaThread *thread = JavaThread::current();
1453   HandleMark hm(thread);
1454 
1455   EVT_TRIG_TRACE(EXT_EVENT_CLASS_UNLOAD, ("[?] Trg Class Unload triggered" ));
1456   if (JvmtiEventController::is_enabled((jvmtiEvent)EXT_EVENT_CLASS_UNLOAD)) {
1457 
1458     JvmtiEnvIterator it;
1459     for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
1460       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1461         continue;
1462       }
1463       if (env->is_enabled((jvmtiEvent)EXT_EVENT_CLASS_UNLOAD)) {
1464         EVT_TRACE(EXT_EVENT_CLASS_UNLOAD, ("[?] Evt Class Unload sent %s", name));
1465 
1466         JvmtiEventMark jem(thread);
1467         JvmtiJavaThreadEventTransition jet(thread);
1468         jvmtiExtensionEvent callback = env->ext_callbacks()->ClassUnload;
1469         if (callback != nullptr) {
1470           (*callback)(env->jvmti_external(), jem.jni_env(), name);
1471         }
1472       }
1473     }
1474   }
1475 }
1476 
1477 
1478 void JvmtiExport::post_thread_start(JavaThread *thread) {
1479   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1480     return;
1481   }
1482   assert(thread->thread_state() == _thread_in_vm, "must be in vm state");
1483 
1484   EVT_TRIG_TRACE(JVMTI_EVENT_THREAD_START, ("[%s] Trg Thread Start event triggered",
1485                       JvmtiTrace::safe_get_thread_name(thread)));
1486 
1487   // do JVMTI thread initialization (if needed)
1488   JvmtiEventController::thread_started(thread);
1489 
1490   if (thread->threadObj()->is_a(vmClasses::BoundVirtualThread_klass())) {
1491     if (JvmtiExport::can_support_virtual_threads()) {
1492       // Check for VirtualThreadStart event instead.
1493       HandleMark hm(thread);
1494       Handle vthread(thread, thread->threadObj());
1495       JvmtiExport::post_vthread_start((jthread)vthread.raw_value());
1496     }
1497     return;
1498   }
1499 
1500   // Do not post thread start event for hidden java thread.
1501   if (JvmtiEventController::is_enabled(JVMTI_EVENT_THREAD_START) &&
1502       !thread->is_hidden_from_external_view()) {
1503     JvmtiEnvIterator it;
1504     for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
1505       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1506         continue;
1507       }
1508       if (env->is_enabled(JVMTI_EVENT_THREAD_START)) {
1509         EVT_TRACE(JVMTI_EVENT_THREAD_START, ("[%s] Evt Thread Start event sent",
1510                      JvmtiTrace::safe_get_thread_name(thread) ));
1511 
1512         JvmtiVirtualThreadEventMark jem(thread);
1513         JvmtiJavaThreadEventTransition jet(thread);
1514         jvmtiEventThreadStart callback = env->callbacks()->ThreadStart;
1515         if (callback != nullptr) {
1516           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread());
1517         }
1518       }
1519     }
1520   }
1521 }
1522 
1523 
1524 void JvmtiExport::post_thread_end(JavaThread *thread) {
1525   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1526     return;
1527   }
1528   EVT_TRIG_TRACE(JVMTI_EVENT_THREAD_END, ("[%s] Trg Thread End event triggered",
1529                       JvmtiTrace::safe_get_thread_name(thread)));
1530 
1531   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1532   if (state == nullptr) {
1533     return;
1534   }
1535 
1536   if (thread->threadObj()->is_a(vmClasses::BoundVirtualThread_klass())) {
1537     if (JvmtiExport::can_support_virtual_threads()) {
1538       // Check for VirtualThreadEnd event instead.
1539       HandleMark hm(thread);
1540       Handle vthread(thread, thread->threadObj());
1541       JvmtiExport::post_vthread_end((jthread)vthread.raw_value());
1542     }
1543     return;
1544   }
1545 
1546   // Do not post thread end event for hidden java thread.
1547   if (state->is_enabled(JVMTI_EVENT_THREAD_END) &&
1548       !thread->is_hidden_from_external_view()) {
1549 
1550     JvmtiEnvThreadStateIterator it(state);
1551     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1552       JvmtiEnv *env = ets->get_env();
1553       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1554         continue;
1555       }
1556       if (ets->is_enabled(JVMTI_EVENT_THREAD_END)) {
1557         EVT_TRACE(JVMTI_EVENT_THREAD_END, ("[%s] Evt Thread End event sent",
1558                      JvmtiTrace::safe_get_thread_name(thread) ));
1559 
1560         JvmtiVirtualThreadEventMark jem(thread);
1561         JvmtiJavaThreadEventTransition jet(thread);
1562         jvmtiEventThreadEnd callback = env->callbacks()->ThreadEnd;
1563         if (callback != nullptr) {
1564           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread());
1565         }
1566       }
1567     }
1568   }
1569 }
1570 
1571 
1572 void JvmtiExport::post_vthread_start(jobject vthread) {
1573   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1574     return;
1575   }
1576   EVT_TRIG_TRACE(JVMTI_EVENT_VIRTUAL_THREAD_START, ("[%p] Trg Virtual Thread Start event triggered", vthread));
1577 
1578   JavaThread *thread = JavaThread::current();
1579   assert(!thread->is_hidden_from_external_view(), "carrier threads can't be hidden");
1580 
1581   if (JvmtiEventController::is_enabled(JVMTI_EVENT_VIRTUAL_THREAD_START)) {
1582     JvmtiEnvIterator it;
1583     for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
1584       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1585         continue;
1586       }
1587       if (env->is_enabled(JVMTI_EVENT_VIRTUAL_THREAD_START)) {
1588         EVT_TRACE(JVMTI_EVENT_VIRTUAL_THREAD_START, ("[%p] Evt Virtual Thread Start event sent", vthread));
1589 
1590         JvmtiVirtualThreadEventMark jem(thread);
1591         JvmtiJavaThreadEventTransition jet(thread);
1592         jvmtiEventVirtualThreadStart callback = env->callbacks()->VirtualThreadStart;
1593         if (callback != nullptr) {
1594           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread());
1595         }
1596       }
1597     }
1598   }
1599 }
1600 
1601 void JvmtiExport::post_vthread_end(jobject vthread) {
1602   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1603     return;
1604   }
1605   EVT_TRIG_TRACE(JVMTI_EVENT_VIRTUAL_THREAD_END, ("[%p] Trg Virtual Thread End event triggered", vthread));
1606 
1607   JavaThread *thread = JavaThread::current();
1608   assert(!thread->is_hidden_from_external_view(), "carrier threads can't be hidden");
1609 
1610   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1611   if (state == nullptr) {
1612     return;
1613   }
1614 
1615   if (state->is_enabled(JVMTI_EVENT_VIRTUAL_THREAD_END)) {
1616     JvmtiEnvThreadStateIterator it(state);
1617 
1618     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1619       JvmtiEnv *env = ets->get_env();
1620       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1621         continue;
1622       }
1623       if (ets->is_enabled(JVMTI_EVENT_VIRTUAL_THREAD_END)) {
1624         EVT_TRACE(JVMTI_EVENT_VIRTUAL_THREAD_END, ("[%p] Evt Virtual Thread End event sent", vthread));
1625 
1626         JvmtiVirtualThreadEventMark jem(thread);
1627         JvmtiJavaThreadEventTransition jet(thread);
1628         jvmtiEventVirtualThreadEnd callback = env->callbacks()->VirtualThreadEnd;
1629         if (callback != nullptr) {
1630           (*callback)(env->jvmti_external(), jem.jni_env(), vthread);
1631         }
1632       }
1633     }
1634   }
1635 }
1636 
1637 void JvmtiExport::post_vthread_mount(jobject vthread) {
1638   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1639     return;
1640   }
1641   JavaThread *thread = JavaThread::current();
1642   HandleMark hm(thread);
1643   EVT_TRIG_TRACE(EXT_EVENT_VIRTUAL_THREAD_MOUNT, ("[%p] Trg Virtual Thread Mount event triggered", vthread));
1644 
1645   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1646   if (state == nullptr) {
1647     return;
1648   }
1649 
1650   if (state->is_enabled((jvmtiEvent)EXT_EVENT_VIRTUAL_THREAD_MOUNT)) {
1651     JvmtiEnvThreadStateIterator it(state);
1652 
1653     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1654       JvmtiEnv *env = ets->get_env();
1655       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1656         continue;
1657       }
1658       if (ets->is_enabled((jvmtiEvent)EXT_EVENT_VIRTUAL_THREAD_MOUNT)) {
1659         EVT_TRACE(EXT_EVENT_VIRTUAL_THREAD_MOUNT, ("[%p] Evt Virtual Thread Mount event sent", vthread));
1660 
1661         JvmtiVirtualThreadEventMark jem(thread);
1662         JvmtiJavaThreadEventTransition jet(thread);
1663         jvmtiExtensionEvent callback = env->ext_callbacks()->VirtualThreadMount;
1664         if (callback != nullptr) {
1665           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread());
1666         }
1667       }
1668     }
1669   }
1670 }
1671 
1672 void JvmtiExport::post_vthread_unmount(jobject vthread) {
1673   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1674     return;
1675   }
1676   JavaThread *thread = JavaThread::current();
1677   HandleMark hm(thread);
1678   EVT_TRIG_TRACE(EXT_EVENT_VIRTUAL_THREAD_UNMOUNT, ("[%p] Trg Virtual Thread Unmount event triggered", vthread));
1679 
1680   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1681   if (state == nullptr) {
1682     return;
1683   }
1684 
1685   if (state->is_enabled((jvmtiEvent)EXT_EVENT_VIRTUAL_THREAD_UNMOUNT)) {
1686     JvmtiEnvThreadStateIterator it(state);
1687 
1688     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1689       JvmtiEnv *env = ets->get_env();
1690       if (env->phase() == JVMTI_PHASE_PRIMORDIAL) {
1691         continue;
1692       }
1693       if (ets->is_enabled((jvmtiEvent)EXT_EVENT_VIRTUAL_THREAD_UNMOUNT)) {
1694         EVT_TRACE(EXT_EVENT_VIRTUAL_THREAD_UNMOUNT, ("[%p] Evt Virtual Thread Unmount event sent", vthread));
1695 
1696         JvmtiVirtualThreadEventMark jem(thread);
1697         JvmtiJavaThreadEventTransition jet(thread);
1698         jvmtiExtensionEvent callback = env->ext_callbacks()->VirtualThreadUnmount;
1699         if (callback != nullptr) {
1700           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread());
1701         }
1702       }
1703     }
1704   }
1705 }
1706 
1707 void JvmtiExport::continuation_yield_cleanup(JavaThread* thread, jint continuation_frame_count) {
1708   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
1709     return;
1710   }
1711 
1712   assert(thread == JavaThread::current(), "must be");
1713   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1714   if (state == nullptr) {
1715     return;
1716   }
1717   state->invalidate_cur_stack_depth();
1718 
1719   // Clear frame_pop requests in frames popped by yield
1720   if (can_post_frame_pop()) {
1721     JvmtiEnvThreadStateIterator it(state);
1722     int top_frame_num = state->cur_stack_depth() + continuation_frame_count;
1723 
1724     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1725       if (!ets->has_frame_pops()) {
1726         continue;
1727       }
1728       for (int frame_idx = 0; frame_idx < continuation_frame_count; frame_idx++) {
1729         int frame_num = top_frame_num - frame_idx;
1730 
1731         if (!state->is_virtual() && ets->is_frame_pop(frame_num)) {
1732           // remove the frame's entry
1733           MutexLocker mu(JvmtiThreadState_lock);
1734           ets->clear_frame_pop(frame_num);
1735         }
1736       }
1737     }
1738   }
1739 }
1740 
1741 void JvmtiExport::post_object_free(JvmtiEnv* env, GrowableArray<jlong>* objects) {
1742   assert(objects != nullptr, "Nothing to post");
1743 
1744   JavaThread *javaThread = JavaThread::current();
1745   if (javaThread->is_in_any_VTMS_transition()) {
1746     return; // no events should be posted if thread is in any VTMS transition
1747   }
1748   if (!env->is_enabled(JVMTI_EVENT_OBJECT_FREE)) {
1749     return; // the event type has been already disabled
1750   }
1751 
1752   EVT_TRIG_TRACE(JVMTI_EVENT_OBJECT_FREE, ("[?] Trg Object Free triggered" ));
1753   EVT_TRACE(JVMTI_EVENT_OBJECT_FREE, ("[?] Evt Object Free sent"));
1754 
1755   JvmtiThreadEventMark jem(javaThread);
1756   JvmtiJavaThreadEventTransition jet(javaThread);
1757   jvmtiEventObjectFree callback = env->callbacks()->ObjectFree;
1758   if (callback != nullptr) {
1759     for (int index = 0; index < objects->length(); index++) {
1760       (*callback)(env->jvmti_external(), objects->at(index));
1761     }
1762   }
1763 }
1764 
1765 void JvmtiExport::post_resource_exhausted(jint resource_exhausted_flags, const char* description) {
1766 
1767   JavaThread *thread  = JavaThread::current();
1768 
1769   if (thread->is_in_any_VTMS_transition()) {
1770     return; // no events should be posted if thread is in any VTMS transition
1771   }
1772 
1773   log_error(jvmti)("Posting Resource Exhausted event: %s",
1774                    description != nullptr ? description : "unknown");
1775 
1776   // JDK-8213834: handlers of ResourceExhausted may attempt some analysis
1777   // which often requires running java.
1778   // This will cause problems on threads not able to run java, e.g. compiler
1779   // threads. To forestall these problems, we therefore suppress sending this
1780   // event from threads which are not able to run java.
1781   if (!thread->can_call_java()) {
1782     return;
1783   }
1784 
1785   EVT_TRIG_TRACE(JVMTI_EVENT_RESOURCE_EXHAUSTED, ("Trg resource exhausted event triggered" ));
1786 
1787   JvmtiEnvIterator it;
1788   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
1789     if (env->is_enabled(JVMTI_EVENT_RESOURCE_EXHAUSTED)) {
1790       EVT_TRACE(JVMTI_EVENT_RESOURCE_EXHAUSTED, ("Evt resource exhausted event sent" ));
1791 
1792       JvmtiThreadEventMark jem(thread);
1793       JvmtiJavaThreadEventTransition jet(thread);
1794       jvmtiEventResourceExhausted callback = env->callbacks()->ResourceExhausted;
1795       if (callback != nullptr) {
1796         (*callback)(env->jvmti_external(), jem.jni_env(),
1797                     resource_exhausted_flags, nullptr, description);
1798       }
1799     }
1800   }
1801 }
1802 
1803 void JvmtiExport::post_method_entry(JavaThread *thread, Method* method, frame current_frame) {
1804   HandleMark hm(thread);
1805   methodHandle mh(thread, method);
1806 
1807   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1808   if (state == nullptr || !state->is_interp_only_mode()) {
1809     // for any thread that actually wants method entry, interp_only_mode is set
1810     return;
1811   }
1812   if (mh->jvmti_mount_transition() || thread->is_in_any_VTMS_transition()) {
1813     return; // no events should be posted if thread is in any VTMS transition
1814   }
1815   EVT_TRIG_TRACE(JVMTI_EVENT_METHOD_ENTRY, ("[%s] Trg Method Entry triggered %s.%s",
1816                      JvmtiTrace::safe_get_thread_name(thread),
1817                      (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1818                      (mh() == nullptr) ? "null" : mh()->name()->as_C_string() ));
1819 
1820   state->incr_cur_stack_depth();
1821 
1822   if (state->is_enabled(JVMTI_EVENT_METHOD_ENTRY)) {
1823     JvmtiEnvThreadStateIterator it(state);
1824     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1825       if (ets->is_enabled(JVMTI_EVENT_METHOD_ENTRY)) {
1826         EVT_TRACE(JVMTI_EVENT_METHOD_ENTRY, ("[%s] Evt Method Entry sent %s.%s",
1827                                              JvmtiTrace::safe_get_thread_name(thread),
1828                                              (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1829                                              (mh() == nullptr) ? "null" : mh()->name()->as_C_string() ));
1830 
1831         JvmtiEnv *env = ets->get_env();
1832         JvmtiMethodEventMark jem(thread, mh);
1833         JvmtiJavaThreadEventTransition jet(thread);
1834         jvmtiEventMethodEntry callback = env->callbacks()->MethodEntry;
1835         if (callback != nullptr) {
1836           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(), jem.jni_methodID());
1837         }
1838       }
1839     }
1840   }
1841 }
1842 
1843 void JvmtiExport::post_method_exit(JavaThread* thread, Method* method, frame current_frame) {
1844   HandleMark hm(thread);
1845   methodHandle mh(thread, method);
1846 
1847   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1848 
1849   if (state == nullptr || !state->is_interp_only_mode()) {
1850     // for any thread that actually wants method exit, interp_only_mode is set
1851     return;
1852   }
1853 
1854   // return a flag when a method terminates by throwing an exception
1855   // i.e. if an exception is thrown and it's not caught by the current method
1856   bool exception_exit = state->is_exception_detected() && !state->is_exception_caught();
1857   Handle result;
1858   jvalue value;
1859   value.j = 0L;
1860 
1861   if (state->is_enabled(JVMTI_EVENT_METHOD_EXIT)) {
1862     // if the method hasn't been popped because of an exception then we populate
1863     // the return_value parameter for the callback. At this point we only have
1864     // the address of a "raw result" and we just call into the interpreter to
1865     // convert this into a jvalue.
1866     if (!exception_exit) {
1867       oop oop_result;
1868       BasicType type = current_frame.interpreter_frame_result(&oop_result, &value);
1869       if (is_reference_type(type)) {
1870         result = Handle(thread, oop_result);
1871         value.l = JNIHandles::make_local(thread, result());
1872       }
1873     }
1874   }
1875 
1876   // Deferred transition to VM, so we can stash away the return oop before GC
1877   // Note that this transition is not needed when throwing an exception, because
1878   // there is no oop to retain.
1879   JavaThread* current = thread; // for JRT_BLOCK
1880   JRT_BLOCK
1881     post_method_exit_inner(thread, mh, state, exception_exit, current_frame, value);
1882   JRT_BLOCK_END
1883 
1884   if (result.not_null() && !mh->is_native()) {
1885     // We have to restore the oop on the stack for interpreter frames
1886     *(oop*)current_frame.interpreter_frame_tos_address() = result();
1887   }
1888 }
1889 
1890 void JvmtiExport::post_method_exit_inner(JavaThread* thread,
1891                                          methodHandle& mh,
1892                                          JvmtiThreadState *state,
1893                                          bool exception_exit,
1894                                          frame current_frame,
1895                                          jvalue& value) {
1896   if (mh->jvmti_mount_transition() || thread->is_in_any_VTMS_transition()) {
1897     return; // no events should be posted if thread is in any VTMS transition
1898   }
1899 
1900   EVT_TRIG_TRACE(JVMTI_EVENT_METHOD_EXIT, ("[%s] Trg Method Exit triggered %s.%s",
1901                                            JvmtiTrace::safe_get_thread_name(thread),
1902                                            (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1903                                            (mh() == nullptr) ? "null" : mh()->name()->as_C_string() ));
1904 
1905   if (state->is_enabled(JVMTI_EVENT_METHOD_EXIT)) {
1906     JvmtiEnvThreadStateIterator it(state);
1907     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1908       if (ets->is_enabled(JVMTI_EVENT_METHOD_EXIT)) {
1909         EVT_TRACE(JVMTI_EVENT_METHOD_EXIT, ("[%s] Evt Method Exit sent %s.%s",
1910                                             JvmtiTrace::safe_get_thread_name(thread),
1911                                             (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1912                                             (mh() == nullptr) ? "null" : mh()->name()->as_C_string() ));
1913 
1914         JvmtiEnv *env = ets->get_env();
1915         JvmtiMethodEventMark jem(thread, mh);
1916         JvmtiJavaThreadEventTransition jet(thread);
1917         jvmtiEventMethodExit callback = env->callbacks()->MethodExit;
1918         if (callback != nullptr) {
1919           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
1920                       jem.jni_methodID(), exception_exit,  value);
1921         }
1922       }
1923     }
1924   }
1925 
1926   JvmtiEnvThreadStateIterator it(state);
1927   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1928     if (ets->has_frame_pops()) {
1929       int cur_frame_number = state->cur_stack_depth();
1930 
1931       if (ets->is_frame_pop(cur_frame_number)) {
1932         // we have a NotifyFramePop entry for this frame.
1933         // now check that this env/thread wants this event
1934         if (ets->is_enabled(JVMTI_EVENT_FRAME_POP)) {
1935           EVT_TRACE(JVMTI_EVENT_FRAME_POP, ("[%s] Evt Frame Pop sent %s.%s",
1936                                             JvmtiTrace::safe_get_thread_name(thread),
1937                                             (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1938                                             (mh() == nullptr) ? "null" : mh()->name()->as_C_string() ));
1939 
1940           // we also need to issue a frame pop event for this frame
1941           JvmtiEnv *env = ets->get_env();
1942           JvmtiMethodEventMark jem(thread, mh);
1943           JvmtiJavaThreadEventTransition jet(thread);
1944           jvmtiEventFramePop callback = env->callbacks()->FramePop;
1945           if (callback != nullptr) {
1946             (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
1947                         jem.jni_methodID(), exception_exit);
1948           }
1949         }
1950         // remove the frame's entry
1951         {
1952           MutexLocker mu(JvmtiThreadState_lock);
1953           ets->clear_frame_pop(cur_frame_number);
1954         }
1955       }
1956     }
1957   }
1958 
1959   state->decr_cur_stack_depth();
1960 }
1961 
1962 
1963 // Todo: inline this for optimization
1964 void JvmtiExport::post_single_step(JavaThread *thread, Method* method, address location) {
1965   HandleMark hm(thread);
1966   methodHandle mh(thread, method);
1967 
1968   JvmtiThreadState *state = get_jvmti_thread_state(thread);
1969   if (state == nullptr) {
1970     return;
1971   }
1972   if (mh->jvmti_mount_transition() || thread->is_in_any_VTMS_transition()) {
1973     return; // no events should be posted if thread is in any VTMS transition
1974   }
1975 
1976   JvmtiEnvThreadStateIterator it(state);
1977   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
1978     ets->compare_and_set_current_location(mh(), location, JVMTI_EVENT_SINGLE_STEP);
1979     if (!ets->single_stepping_posted() && ets->is_enabled(JVMTI_EVENT_SINGLE_STEP)) {
1980       EVT_TRACE(JVMTI_EVENT_SINGLE_STEP, ("[%s] Evt Single Step sent %s.%s @ " INTX_FORMAT,
1981                     JvmtiTrace::safe_get_thread_name(thread),
1982                     (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
1983                     (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
1984                     location - mh()->code_base() ));
1985 
1986       JvmtiEnv *env = ets->get_env();
1987       JvmtiLocationEventMark jem(thread, mh, location);
1988       JvmtiJavaThreadEventTransition jet(thread);
1989       jvmtiEventSingleStep callback = env->callbacks()->SingleStep;
1990       if (callback != nullptr) {
1991         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
1992                     jem.jni_methodID(), jem.location());
1993       }
1994 
1995       ets->set_single_stepping_posted();
1996     }
1997   }
1998 }
1999 
2000 void JvmtiExport::post_exception_throw(JavaThread *thread, Method* method, address location, oop exception) {
2001   HandleMark hm(thread);
2002   methodHandle mh(thread, method);
2003   Handle exception_handle(thread, exception);
2004   // The KeepStackGCProcessedMark below keeps the target thread and its stack fully
2005   // GC processed across this scope. This is needed because there is a stack walk
2006   // below with safepoint polls inside of it. After such safepoints, we have to
2007   // ensure the stack is sufficiently processed.
2008   KeepStackGCProcessedMark ksgcpm(thread);
2009 
2010   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2011   if (state == nullptr) {
2012     return;
2013   }
2014   if (thread->is_in_any_VTMS_transition()) {
2015     return; // no events should be posted if thread is in any VTMS transition
2016   }
2017 
2018   EVT_TRIG_TRACE(JVMTI_EVENT_EXCEPTION, ("[%s] Trg Exception thrown triggered",
2019                       JvmtiTrace::safe_get_thread_name(thread)));
2020   if (!state->is_exception_detected()) {
2021     state->set_exception_detected();
2022     JvmtiEnvThreadStateIterator it(state);
2023     for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2024       if (ets->is_enabled(JVMTI_EVENT_EXCEPTION) && (exception != nullptr)) {
2025 
2026         EVT_TRACE(JVMTI_EVENT_EXCEPTION,
2027                      ("[%s] Evt Exception thrown sent %s.%s @ " INTX_FORMAT,
2028                       JvmtiTrace::safe_get_thread_name(thread),
2029                       (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
2030                       (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
2031                       location - mh()->code_base() ));
2032 
2033         JvmtiEnv *env = ets->get_env();
2034         JvmtiExceptionEventMark jem(thread, mh, location, exception_handle);
2035 
2036         // It's okay to clear these exceptions here because we duplicate
2037         // this lookup in InterpreterRuntime::exception_handler_for_exception.
2038         EXCEPTION_MARK;
2039 
2040         bool should_repeat;
2041         vframeStream st(thread);
2042         assert(!st.at_end(), "cannot be at end");
2043         Method* current_method = nullptr;
2044         // A GC may occur during the Method::fast_exception_handler_bci_for()
2045         // call below if it needs to load the constraint class. Using a
2046         // methodHandle to keep the 'current_method' from being deallocated
2047         // if GC happens.
2048         methodHandle current_mh = methodHandle(thread, current_method);
2049         int current_bci = -1;
2050         do {
2051           current_method = st.method();
2052           current_mh = methodHandle(thread, current_method);
2053           current_bci = st.bci();
2054           do {
2055             should_repeat = false;
2056             Klass* eh_klass = exception_handle()->klass();
2057             current_bci = Method::fast_exception_handler_bci_for(
2058               current_mh, eh_klass, current_bci, THREAD);
2059             if (HAS_PENDING_EXCEPTION) {
2060               exception_handle = Handle(thread, PENDING_EXCEPTION);
2061               CLEAR_PENDING_EXCEPTION;
2062               should_repeat = true;
2063             }
2064           } while (should_repeat && (current_bci != -1));
2065           st.next();
2066         } while ((current_bci < 0) && (!st.at_end()));
2067 
2068         jmethodID catch_jmethodID;
2069         if (current_bci < 0) {
2070           catch_jmethodID = 0;
2071           current_bci = 0;
2072         } else {
2073           catch_jmethodID = jem.to_jmethodID(current_mh);
2074         }
2075 
2076         JvmtiJavaThreadEventTransition jet(thread);
2077         jvmtiEventException callback = env->callbacks()->Exception;
2078         if (callback != nullptr) {
2079           (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2080                       jem.jni_methodID(), jem.location(),
2081                       jem.exception(),
2082                       catch_jmethodID, current_bci);
2083         }
2084       }
2085     }
2086   }
2087 
2088   // frames may get popped because of this throw, be safe - invalidate cached depth
2089   state->invalidate_cur_stack_depth();
2090 }
2091 
2092 
2093 void JvmtiExport::notice_unwind_due_to_exception(JavaThread *thread, Method* method, address location, oop exception, bool in_handler_frame) {
2094   HandleMark hm(thread);
2095   methodHandle mh(thread, method);
2096   Handle exception_handle(thread, exception);
2097 
2098   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2099   if (state == nullptr) {
2100     return;
2101   }
2102   EVT_TRIG_TRACE(JVMTI_EVENT_EXCEPTION_CATCH,
2103                     ("[%s] Trg unwind_due_to_exception triggered %s.%s @ %s" INTX_FORMAT " - %s",
2104                      JvmtiTrace::safe_get_thread_name(thread),
2105                      (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
2106                      (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
2107                      location==0? "no location:" : "",
2108                      location==0? 0 : location - mh()->code_base(),
2109                      in_handler_frame? "in handler frame" : "not handler frame" ));
2110 
2111   if (state->is_exception_detected()) {
2112 
2113     state->invalidate_cur_stack_depth();
2114     if (!in_handler_frame) {
2115       // Not in exception handler.
2116       if(state->is_interp_only_mode()) {
2117         // method exit and frame pop events are posted only in interp mode.
2118         // When these events are enabled code should be in running in interp mode.
2119         jvalue no_value;
2120         no_value.j = 0L;
2121         JvmtiExport::post_method_exit_inner(thread, mh, state, true, thread->last_frame(), no_value);
2122         // The cached cur_stack_depth might have changed from the
2123         // operations of frame pop or method exit. We are not 100% sure
2124         // the cached cur_stack_depth is still valid depth so invalidate
2125         // it.
2126         state->invalidate_cur_stack_depth();
2127       }
2128     } else {
2129       // In exception handler frame. Report exception catch.
2130       assert(location != nullptr, "must be a known location");
2131       // Update cur_stack_depth - the frames above the current frame
2132       // have been unwound due to this exception:
2133       assert(!state->is_exception_caught(), "exception must not be caught yet.");
2134       state->set_exception_caught();
2135 
2136       if (mh->jvmti_mount_transition() || thread->is_in_any_VTMS_transition()) {
2137         return; // no events should be posted if thread is in any VTMS transition
2138       }
2139       JvmtiEnvThreadStateIterator it(state);
2140       for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2141         if (ets->is_enabled(JVMTI_EVENT_EXCEPTION_CATCH) && (exception_handle() != nullptr)) {
2142           EVT_TRACE(JVMTI_EVENT_EXCEPTION_CATCH,
2143                      ("[%s] Evt ExceptionCatch sent %s.%s @ " INTX_FORMAT,
2144                       JvmtiTrace::safe_get_thread_name(thread),
2145                       (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
2146                       (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
2147                       location - mh()->code_base() ));
2148 
2149           JvmtiEnv *env = ets->get_env();
2150           JvmtiExceptionEventMark jem(thread, mh, location, exception_handle);
2151           JvmtiJavaThreadEventTransition jet(thread);
2152           jvmtiEventExceptionCatch callback = env->callbacks()->ExceptionCatch;
2153           if (callback != nullptr) {
2154             (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2155                       jem.jni_methodID(), jem.location(),
2156                       jem.exception());
2157           }
2158         }
2159       }
2160     }
2161   }
2162 }
2163 
2164 oop JvmtiExport::jni_GetField_probe(JavaThread *thread, jobject jobj, oop obj,
2165                                     Klass* klass, jfieldID fieldID, bool is_static) {
2166   if (*((int *)get_field_access_count_addr()) > 0 && thread->has_last_Java_frame()) {
2167     // At least one field access watch is set so we have more work to do.
2168     post_field_access_by_jni(thread, obj, klass, fieldID, is_static);
2169     // event posting can block so refetch oop if we were passed a jobj
2170     if (jobj != nullptr) return JNIHandles::resolve_non_null(jobj);
2171   }
2172   return obj;
2173 }
2174 
2175 void JvmtiExport::post_field_access_by_jni(JavaThread *thread, oop obj,
2176                                            Klass* klass, jfieldID fieldID, bool is_static) {
2177   // We must be called with a Java context in order to provide reasonable
2178   // values for the klazz, method, and location fields. The callers of this
2179   // function don't make the call unless there is a Java context.
2180   assert(thread->has_last_Java_frame(), "must be called with a Java context");
2181 
2182   if (thread->is_in_any_VTMS_transition()) {
2183     return; // no events should be posted if thread is in any VTMS transition
2184   }
2185 
2186   ResourceMark rm;
2187   fieldDescriptor fd;
2188   // if get_field_descriptor finds fieldID to be invalid, then we just bail
2189   bool valid_fieldID = JvmtiEnv::get_field_descriptor(klass, fieldID, &fd);
2190   assert(valid_fieldID == true,"post_field_access_by_jni called with invalid fieldID");
2191   if (!valid_fieldID) return;
2192   // field accesses are not watched so bail
2193   if (!fd.is_field_access_watched()) return;
2194 
2195   HandleMark hm(thread);
2196   Handle h_obj;
2197   if (!is_static) {
2198     // non-static field accessors have an object, but we need a handle
2199     assert(obj != nullptr, "non-static needs an object");
2200     h_obj = Handle(thread, obj);
2201   }
2202   post_field_access(thread,
2203                     thread->last_frame().interpreter_frame_method(),
2204                     thread->last_frame().interpreter_frame_bcp(),
2205                     klass, h_obj, fieldID);
2206 }
2207 
2208 void JvmtiExport::post_field_access(JavaThread *thread, Method* method,
2209   address location, Klass* field_klass, Handle object, jfieldID field) {
2210 
2211   HandleMark hm(thread);
2212   methodHandle mh(thread, method);
2213 
2214   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2215   if (state == nullptr) {
2216     return;
2217   }
2218   if (thread->is_in_any_VTMS_transition()) {
2219     return; // no events should be posted if thread is in any VTMS transition
2220   }
2221 
2222   EVT_TRIG_TRACE(JVMTI_EVENT_FIELD_ACCESS, ("[%s] Trg Field Access event triggered",
2223                       JvmtiTrace::safe_get_thread_name(thread)));
2224   JvmtiEnvThreadStateIterator it(state);
2225   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2226     if (ets->is_enabled(JVMTI_EVENT_FIELD_ACCESS)) {
2227       EVT_TRACE(JVMTI_EVENT_FIELD_ACCESS, ("[%s] Evt Field Access event sent %s.%s @ " INTX_FORMAT,
2228                      JvmtiTrace::safe_get_thread_name(thread),
2229                      (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
2230                      (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
2231                      location - mh()->code_base() ));
2232 
2233       JvmtiEnv *env = ets->get_env();
2234       JvmtiLocationEventMark jem(thread, mh, location);
2235       jclass field_jclass = jem.to_jclass(field_klass);
2236       jobject field_jobject = jem.to_jobject(object());
2237       JvmtiJavaThreadEventTransition jet(thread);
2238       jvmtiEventFieldAccess callback = env->callbacks()->FieldAccess;
2239       if (callback != nullptr) {
2240         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2241                     jem.jni_methodID(), jem.location(),
2242                     field_jclass, field_jobject, field);
2243       }
2244     }
2245   }
2246 }
2247 
2248 oop JvmtiExport::jni_SetField_probe(JavaThread *thread, jobject jobj, oop obj,
2249                                     Klass* klass, jfieldID fieldID, bool is_static,
2250                                     char sig_type, jvalue *value) {
2251   if (*((int *)get_field_modification_count_addr()) > 0 && thread->has_last_Java_frame()) {
2252     // At least one field modification watch is set so we have more work to do.
2253     post_field_modification_by_jni(thread, obj, klass, fieldID, is_static, sig_type, value);
2254     // event posting can block so refetch oop if we were passed a jobj
2255     if (jobj != nullptr) return JNIHandles::resolve_non_null(jobj);
2256   }
2257   return obj;
2258 }
2259 
2260 void JvmtiExport::post_field_modification_by_jni(JavaThread *thread, oop obj,
2261                                                  Klass* klass, jfieldID fieldID, bool is_static,
2262                                                  char sig_type, jvalue *value) {
2263   // We must be called with a Java context in order to provide reasonable
2264   // values for the klazz, method, and location fields. The callers of this
2265   // function don't make the call unless there is a Java context.
2266   assert(thread->has_last_Java_frame(), "must be called with Java context");
2267 
2268   if (thread->is_in_any_VTMS_transition()) {
2269     return; // no events should be posted if thread is in any VTMS transition
2270   }
2271 
2272   ResourceMark rm;
2273   fieldDescriptor fd;
2274   // if get_field_descriptor finds fieldID to be invalid, then we just bail
2275   bool valid_fieldID = JvmtiEnv::get_field_descriptor(klass, fieldID, &fd);
2276   assert(valid_fieldID == true,"post_field_modification_by_jni called with invalid fieldID");
2277   if (!valid_fieldID) return;
2278   // field modifications are not watched so bail
2279   if (!fd.is_field_modification_watched()) return;
2280 
2281   HandleMark hm(thread);
2282 
2283   Handle h_obj;
2284   if (!is_static) {
2285     // non-static field accessors have an object, but we need a handle
2286     assert(obj != nullptr, "non-static needs an object");
2287     h_obj = Handle(thread, obj);
2288   }
2289   post_field_modification(thread,
2290                           thread->last_frame().interpreter_frame_method(),
2291                           thread->last_frame().interpreter_frame_bcp(),
2292                           klass, h_obj, fieldID, sig_type, value);
2293 }
2294 
2295 void JvmtiExport::post_raw_field_modification(JavaThread *thread, Method* method,
2296   address location, Klass* field_klass, Handle object, jfieldID field,
2297   char sig_type, jvalue *value) {
2298 
2299   if (thread->is_in_any_VTMS_transition()) {
2300     return; // no events should be posted if thread is in any VTMS transition
2301   }
2302 
2303   if (sig_type == JVM_SIGNATURE_INT || sig_type == JVM_SIGNATURE_BOOLEAN ||
2304       sig_type == JVM_SIGNATURE_BYTE || sig_type == JVM_SIGNATURE_CHAR ||
2305       sig_type == JVM_SIGNATURE_SHORT) {
2306     // 'I' instructions are used for byte, char, short and int.
2307     // determine which it really is, and convert
2308     fieldDescriptor fd;
2309     bool found = JvmtiEnv::get_field_descriptor(field_klass, field, &fd);
2310     // should be found (if not, leave as is)
2311     if (found) {
2312       jint ival = value->i;
2313       // convert value from int to appropriate type
2314       switch (fd.field_type()) {
2315       case T_BOOLEAN:
2316         sig_type = JVM_SIGNATURE_BOOLEAN;
2317         value->i = 0; // clear it
2318         value->z = (jboolean)ival;
2319         break;
2320       case T_BYTE:
2321         sig_type = JVM_SIGNATURE_BYTE;
2322         value->i = 0; // clear it
2323         value->b = (jbyte)ival;
2324         break;
2325       case T_CHAR:
2326         sig_type = JVM_SIGNATURE_CHAR;
2327         value->i = 0; // clear it
2328         value->c = (jchar)ival;
2329         break;
2330       case T_SHORT:
2331         sig_type = JVM_SIGNATURE_SHORT;
2332         value->i = 0; // clear it
2333         value->s = (jshort)ival;
2334         break;
2335       case T_INT:
2336         // nothing to do
2337         break;
2338       default:
2339         // this is an integer instruction, should be one of above
2340         ShouldNotReachHere();
2341         break;
2342       }
2343     }
2344   }
2345 
2346   assert(sig_type != JVM_SIGNATURE_ARRAY, "array should have sig_type == 'L'");
2347   bool handle_created = false;
2348 
2349   // convert oop to JNI handle.
2350   if (sig_type == JVM_SIGNATURE_CLASS || sig_type == JVM_SIGNATURE_PRIMITIVE_OBJECT) {
2351     handle_created = true;
2352     value->l = (jobject)JNIHandles::make_local(thread, cast_to_oop(value->l));
2353   }
2354 
2355   post_field_modification(thread, method, location, field_klass, object, field, sig_type, value);
2356 
2357   // Destroy the JNI handle allocated above.
2358   if (handle_created) {
2359     JNIHandles::destroy_local(value->l);
2360   }
2361 }
2362 
2363 void JvmtiExport::post_field_modification(JavaThread *thread, Method* method,
2364   address location, Klass* field_klass, Handle object, jfieldID field,
2365   char sig_type, jvalue *value_ptr) {
2366 
2367   HandleMark hm(thread);
2368   methodHandle mh(thread, method);
2369 
2370   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2371   if (state == nullptr) {
2372     return;
2373   }
2374   if (thread->is_in_any_VTMS_transition()) {
2375     return; // no events should be posted if thread is in any VTMS transition
2376   }
2377 
2378   EVT_TRIG_TRACE(JVMTI_EVENT_FIELD_MODIFICATION,
2379                      ("[%s] Trg Field Modification event triggered",
2380                       JvmtiTrace::safe_get_thread_name(thread)));
2381   JvmtiEnvThreadStateIterator it(state);
2382   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2383     if (ets->is_enabled(JVMTI_EVENT_FIELD_MODIFICATION)) {
2384       EVT_TRACE(JVMTI_EVENT_FIELD_MODIFICATION,
2385                    ("[%s] Evt Field Modification event sent %s.%s @ " INTX_FORMAT,
2386                     JvmtiTrace::safe_get_thread_name(thread),
2387                     (mh() == nullptr) ? "null" : mh()->klass_name()->as_C_string(),
2388                     (mh() == nullptr) ? "null" : mh()->name()->as_C_string(),
2389                     location - mh()->code_base() ));
2390 
2391       JvmtiEnv *env = ets->get_env();
2392       JvmtiLocationEventMark jem(thread, mh, location);
2393       jclass field_jclass = jem.to_jclass(field_klass);
2394       jobject field_jobject = jem.to_jobject(object());
2395       JvmtiJavaThreadEventTransition jet(thread);
2396       jvmtiEventFieldModification callback = env->callbacks()->FieldModification;
2397       if (callback != nullptr) {
2398         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2399                     jem.jni_methodID(), jem.location(),
2400                     field_jclass, field_jobject, field, sig_type, *value_ptr);
2401       }
2402     }
2403   }
2404 }
2405 
2406 void JvmtiExport::post_native_method_bind(Method* method, address* function_ptr) {
2407   JavaThread* thread = JavaThread::current();
2408   assert(thread->thread_state() == _thread_in_vm, "must be in vm state");
2409 
2410   HandleMark hm(thread);
2411   methodHandle mh(thread, method);
2412 
2413   if (thread->is_in_any_VTMS_transition()) {
2414     return; // no events should be posted if thread is in any VTMS transition
2415   }
2416   EVT_TRIG_TRACE(JVMTI_EVENT_NATIVE_METHOD_BIND, ("[%s] Trg Native Method Bind event triggered",
2417                       JvmtiTrace::safe_get_thread_name(thread)));
2418 
2419   if (JvmtiEventController::is_enabled(JVMTI_EVENT_NATIVE_METHOD_BIND)) {
2420     JvmtiEnvIterator it;
2421     for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2422       if (env->is_enabled(JVMTI_EVENT_NATIVE_METHOD_BIND)) {
2423         EVT_TRACE(JVMTI_EVENT_NATIVE_METHOD_BIND, ("[%s] Evt Native Method Bind event sent",
2424                      JvmtiTrace::safe_get_thread_name(thread) ));
2425 
2426         JvmtiMethodEventMark jem(thread, mh);
2427         JvmtiJavaThreadEventTransition jet(thread);
2428         JNIEnv* jni_env = (env->phase() == JVMTI_PHASE_PRIMORDIAL) ? nullptr : jem.jni_env();
2429         jvmtiEventNativeMethodBind callback = env->callbacks()->NativeMethodBind;
2430         if (callback != nullptr) {
2431           (*callback)(env->jvmti_external(), jni_env, jem.jni_thread(),
2432                       jem.jni_methodID(), (void*)(*function_ptr), (void**)function_ptr);
2433         }
2434       }
2435     }
2436   }
2437 }
2438 
2439 // Returns a record containing inlining information for the given nmethod
2440 jvmtiCompiledMethodLoadInlineRecord* create_inline_record(nmethod* nm) {
2441   jint numstackframes = 0;
2442   jvmtiCompiledMethodLoadInlineRecord* record = (jvmtiCompiledMethodLoadInlineRecord*)NEW_RESOURCE_OBJ(jvmtiCompiledMethodLoadInlineRecord);
2443   record->header.kind = JVMTI_CMLR_INLINE_INFO;
2444   record->header.next = nullptr;
2445   record->header.majorinfoversion = JVMTI_CMLR_MAJOR_VERSION_1;
2446   record->header.minorinfoversion = JVMTI_CMLR_MINOR_VERSION_0;
2447   record->numpcs = 0;
2448   for(PcDesc* p = nm->scopes_pcs_begin(); p < nm->scopes_pcs_end(); p++) {
2449    if(p->scope_decode_offset() == DebugInformationRecorder::serialized_null) continue;
2450    record->numpcs++;
2451   }
2452   record->pcinfo = (PCStackInfo*)(NEW_RESOURCE_ARRAY(PCStackInfo, record->numpcs));
2453   int scope = 0;
2454   for(PcDesc* p = nm->scopes_pcs_begin(); p < nm->scopes_pcs_end(); p++) {
2455     if(p->scope_decode_offset() == DebugInformationRecorder::serialized_null) continue;
2456     void* pc_address = (void*)p->real_pc(nm);
2457     assert(pc_address != nullptr, "pc_address must be non-null");
2458     record->pcinfo[scope].pc = pc_address;
2459     numstackframes=0;
2460     for(ScopeDesc* sd = nm->scope_desc_at(p->real_pc(nm));sd != nullptr;sd = sd->sender()) {
2461       numstackframes++;
2462     }
2463     assert(numstackframes != 0, "numstackframes must be nonzero.");
2464     record->pcinfo[scope].methods = (jmethodID *)NEW_RESOURCE_ARRAY(jmethodID, numstackframes);
2465     record->pcinfo[scope].bcis = (jint *)NEW_RESOURCE_ARRAY(jint, numstackframes);
2466     record->pcinfo[scope].numstackframes = numstackframes;
2467     int stackframe = 0;
2468     for(ScopeDesc* sd = nm->scope_desc_at(p->real_pc(nm));sd != nullptr;sd = sd->sender()) {
2469       // sd->method() can be null for stubs but not for nmethods. To be completely robust, include an assert that we should never see a null sd->method()
2470       guarantee(sd->method() != nullptr, "sd->method() cannot be null.");
2471       record->pcinfo[scope].methods[stackframe] = sd->method()->jmethod_id();
2472       record->pcinfo[scope].bcis[stackframe] = sd->bci();
2473       stackframe++;
2474     }
2475     scope++;
2476   }
2477   return record;
2478 }
2479 
2480 void JvmtiExport::post_compiled_method_load(nmethod *nm) {
2481   guarantee(!nm->is_unloading(), "nmethod isn't unloaded or unloading");
2482   if (JvmtiEnv::get_phase() < JVMTI_PHASE_PRIMORDIAL) {
2483     return;
2484   }
2485   JavaThread* thread = JavaThread::current();
2486 
2487   assert(!thread->is_in_any_VTMS_transition(), "compiled method load events are not allowed in any VTMS transition");
2488 
2489   EVT_TRIG_TRACE(JVMTI_EVENT_COMPILED_METHOD_LOAD,
2490                  ("[%s] method compile load event triggered",
2491                  JvmtiTrace::safe_get_thread_name(thread)));
2492 
2493   JvmtiEnvIterator it;
2494   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2495     post_compiled_method_load(env, nm);
2496   }
2497 }
2498 
2499 // post a COMPILED_METHOD_LOAD event for a given environment
2500 void JvmtiExport::post_compiled_method_load(JvmtiEnv* env, nmethod *nm) {
2501   if (env->phase() == JVMTI_PHASE_PRIMORDIAL || !env->is_enabled(JVMTI_EVENT_COMPILED_METHOD_LOAD)) {
2502     return;
2503   }
2504   jvmtiEventCompiledMethodLoad callback = env->callbacks()->CompiledMethodLoad;
2505   if (callback == nullptr) {
2506     return;
2507   }
2508   JavaThread* thread = JavaThread::current();
2509 
2510   assert(!thread->is_in_any_VTMS_transition(), "compiled method load events are not allowed in any VTMS transition");
2511 
2512   EVT_TRACE(JVMTI_EVENT_COMPILED_METHOD_LOAD,
2513            ("[%s] method compile load event sent %s.%s  ",
2514             JvmtiTrace::safe_get_thread_name(thread),
2515             (nm->method() == nullptr) ? "null" : nm->method()->klass_name()->as_C_string(),
2516             (nm->method() == nullptr) ? "null" : nm->method()->name()->as_C_string()));
2517   ResourceMark rm(thread);
2518   HandleMark hm(thread);
2519 
2520   // Add inlining information
2521   jvmtiCompiledMethodLoadInlineRecord* inlinerecord = create_inline_record(nm);
2522   // Pass inlining information through the void pointer
2523   JvmtiCompiledMethodLoadEventMark jem(thread, nm, inlinerecord);
2524   JvmtiJavaThreadEventTransition jet(thread);
2525   (*callback)(env->jvmti_external(), jem.jni_methodID(),
2526               jem.code_size(), jem.code_data(), jem.map_length(),
2527               jem.map(), jem.compile_info());
2528 }
2529 
2530 void JvmtiExport::post_dynamic_code_generated_internal(const char *name, const void *code_begin, const void *code_end) {
2531   assert(name != nullptr && name[0] != '\0', "sanity check");
2532 
2533   JavaThread* thread = JavaThread::current();
2534 
2535   assert(!thread->is_in_any_VTMS_transition(), "dynamic code generated events are not allowed in any VTMS transition");
2536 
2537   // In theory everyone coming thru here is in_vm but we need to be certain
2538   // because a callee will do a vm->native transition
2539   ThreadInVMfromUnknown __tiv;
2540 
2541   EVT_TRIG_TRACE(JVMTI_EVENT_DYNAMIC_CODE_GENERATED,
2542                  ("[%s] method dynamic code generated event triggered",
2543                  JvmtiTrace::safe_get_thread_name(thread)));
2544   JvmtiEnvIterator it;
2545   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2546     if (env->is_enabled(JVMTI_EVENT_DYNAMIC_CODE_GENERATED)) {
2547       EVT_TRACE(JVMTI_EVENT_DYNAMIC_CODE_GENERATED,
2548                 ("[%s] dynamic code generated event sent for %s",
2549                 JvmtiTrace::safe_get_thread_name(thread), name));
2550       JvmtiEventMark jem(thread);
2551       JvmtiJavaThreadEventTransition jet(thread);
2552       jint length = (jint)pointer_delta(code_end, code_begin, sizeof(char));
2553       jvmtiEventDynamicCodeGenerated callback = env->callbacks()->DynamicCodeGenerated;
2554       if (callback != nullptr) {
2555         (*callback)(env->jvmti_external(), name, (void*)code_begin, length);
2556       }
2557     }
2558   }
2559 }
2560 
2561 void JvmtiExport::post_dynamic_code_generated(const char *name, const void *code_begin, const void *code_end) {
2562   jvmtiPhase phase = JvmtiEnv::get_phase();
2563   if (phase == JVMTI_PHASE_PRIMORDIAL || phase == JVMTI_PHASE_START) {
2564     post_dynamic_code_generated_internal(name, code_begin, code_end);
2565   } else {
2566     // It may not be safe to post the event from this thread.  Defer all
2567     // postings to the service thread so that it can perform them in a safe
2568     // context and in-order.
2569     JvmtiDeferredEvent event = JvmtiDeferredEvent::dynamic_code_generated_event(
2570         name, code_begin, code_end);
2571     ServiceThread::enqueue_deferred_event(&event);
2572   }
2573 }
2574 
2575 
2576 // post a DYNAMIC_CODE_GENERATED event for a given environment
2577 // used by GenerateEvents
2578 void JvmtiExport::post_dynamic_code_generated(JvmtiEnv* env, const char *name,
2579                                               const void *code_begin, const void *code_end)
2580 {
2581   JavaThread* thread = JavaThread::current();
2582 
2583   assert(!thread->is_in_any_VTMS_transition(), "dynamic code generated events are not allowed in any VTMS transition");
2584 
2585   EVT_TRIG_TRACE(JVMTI_EVENT_DYNAMIC_CODE_GENERATED,
2586                  ("[%s] dynamic code generated event triggered (by GenerateEvents)",
2587                   JvmtiTrace::safe_get_thread_name(thread)));
2588   if (env->is_enabled(JVMTI_EVENT_DYNAMIC_CODE_GENERATED)) {
2589     EVT_TRACE(JVMTI_EVENT_DYNAMIC_CODE_GENERATED,
2590               ("[%s] dynamic code generated event sent for %s",
2591                JvmtiTrace::safe_get_thread_name(thread), name));
2592     JvmtiEventMark jem(thread);
2593     JvmtiJavaThreadEventTransition jet(thread);
2594     jint length = (jint)pointer_delta(code_end, code_begin, sizeof(char));
2595     jvmtiEventDynamicCodeGenerated callback = env->callbacks()->DynamicCodeGenerated;
2596     if (callback != nullptr) {
2597       (*callback)(env->jvmti_external(), name, (void*)code_begin, length);
2598     }
2599   }
2600 }
2601 
2602 // post a DynamicCodeGenerated event while holding locks in the VM.
2603 void JvmtiExport::post_dynamic_code_generated_while_holding_locks(const char* name,
2604                                                                   address code_begin, address code_end)
2605 {
2606   JavaThread* thread = JavaThread::current();
2607   // register the stub with the current dynamic code event collector
2608   // Cannot take safepoint here so do not use state_for to get
2609   // jvmti thread state.
2610   // The collector and/or state might be null if JvmtiDynamicCodeEventCollector
2611   // has been initialized while JVMTI_EVENT_DYNAMIC_CODE_GENERATED was disabled.
2612   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2613   if (state != nullptr) {
2614     JvmtiDynamicCodeEventCollector *collector = state->get_dynamic_code_event_collector();
2615     if (collector != nullptr) {
2616       collector->register_stub(name, code_begin, code_end);
2617     }
2618   }
2619 }
2620 
2621 // Collect all the vm internally allocated objects which are visible to java world
2622 void JvmtiExport::record_vm_internal_object_allocation(oop obj) {
2623   Thread* thread = Thread::current_or_null();
2624   if (thread != nullptr && thread->is_Java_thread())  {
2625     // Can not take safepoint here.
2626     NoSafepointVerifier no_sfpt;
2627     // Cannot take safepoint here so do not use state_for to get
2628     // jvmti thread state.
2629     JvmtiThreadState *state = JavaThread::cast(thread)->jvmti_thread_state();
2630     if (state != nullptr) {
2631       // state is non null when VMObjectAllocEventCollector is enabled.
2632       JvmtiVMObjectAllocEventCollector *collector;
2633       collector = state->get_vm_object_alloc_event_collector();
2634       if (collector != nullptr && collector->is_enabled()) {
2635         // Don't record classes as these will be notified via the ClassLoad
2636         // event.
2637         if (obj->klass() != vmClasses::Class_klass()) {
2638           collector->record_allocation(obj);
2639         }
2640       }
2641     }
2642   }
2643 }
2644 
2645 // Collect all the sampled allocated objects.
2646 void JvmtiExport::record_sampled_internal_object_allocation(oop obj) {
2647   Thread* thread = Thread::current_or_null();
2648   if (thread != nullptr && thread->is_Java_thread())  {
2649     // Can not take safepoint here.
2650     NoSafepointVerifier no_sfpt;
2651     // Cannot take safepoint here so do not use state_for to get
2652     // jvmti thread state.
2653     JvmtiThreadState *state = JavaThread::cast(thread)->jvmti_thread_state();
2654     if (state != nullptr) {
2655       // state is non null when SampledObjectAllocEventCollector is enabled.
2656       JvmtiSampledObjectAllocEventCollector *collector;
2657       collector = state->get_sampled_object_alloc_event_collector();
2658 
2659       if (collector != nullptr && collector->is_enabled()) {
2660         collector->record_allocation(obj);
2661       }
2662     }
2663   }
2664 }
2665 
2666 void JvmtiExport::post_garbage_collection_finish() {
2667   Thread *thread = Thread::current(); // this event is posted from VM-Thread.
2668   EVT_TRIG_TRACE(JVMTI_EVENT_GARBAGE_COLLECTION_FINISH,
2669                  ("[%s] garbage collection finish event triggered",
2670                   JvmtiTrace::safe_get_thread_name(thread)));
2671   JvmtiEnvIterator it;
2672   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2673     if (env->is_enabled(JVMTI_EVENT_GARBAGE_COLLECTION_FINISH)) {
2674       EVT_TRACE(JVMTI_EVENT_GARBAGE_COLLECTION_FINISH,
2675                 ("[%s] garbage collection finish event sent",
2676                  JvmtiTrace::safe_get_thread_name(thread)));
2677       JvmtiThreadEventTransition jet(thread);
2678       // JNIEnv is null here because this event is posted from VM Thread
2679       jvmtiEventGarbageCollectionFinish callback = env->callbacks()->GarbageCollectionFinish;
2680       if (callback != nullptr) {
2681         (*callback)(env->jvmti_external());
2682       }
2683     }
2684   }
2685 }
2686 
2687 void JvmtiExport::post_garbage_collection_start() {
2688   Thread* thread = Thread::current(); // this event is posted from vm-thread.
2689   EVT_TRIG_TRACE(JVMTI_EVENT_GARBAGE_COLLECTION_START,
2690                  ("[%s] garbage collection start event triggered",
2691                   JvmtiTrace::safe_get_thread_name(thread)));
2692   JvmtiEnvIterator it;
2693   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2694     if (env->is_enabled(JVMTI_EVENT_GARBAGE_COLLECTION_START)) {
2695       EVT_TRACE(JVMTI_EVENT_GARBAGE_COLLECTION_START,
2696                 ("[%s] garbage collection start event sent",
2697                  JvmtiTrace::safe_get_thread_name(thread)));
2698       JvmtiThreadEventTransition jet(thread);
2699       // JNIEnv is null here because this event is posted from VM Thread
2700       jvmtiEventGarbageCollectionStart callback = env->callbacks()->GarbageCollectionStart;
2701       if (callback != nullptr) {
2702         (*callback)(env->jvmti_external());
2703       }
2704     }
2705   }
2706 }
2707 
2708 void JvmtiExport::post_data_dump() {
2709   Thread *thread = Thread::current();
2710   EVT_TRIG_TRACE(JVMTI_EVENT_DATA_DUMP_REQUEST,
2711                  ("[%s] data dump request event triggered",
2712                   JvmtiTrace::safe_get_thread_name(thread)));
2713   JvmtiEnvIterator it;
2714   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2715     if (env->is_enabled(JVMTI_EVENT_DATA_DUMP_REQUEST)) {
2716       EVT_TRACE(JVMTI_EVENT_DATA_DUMP_REQUEST,
2717                 ("[%s] data dump request event sent",
2718                  JvmtiTrace::safe_get_thread_name(thread)));
2719      JvmtiThreadEventTransition jet(thread);
2720      // JNIEnv is null here because this event is posted from VM Thread
2721      jvmtiEventDataDumpRequest callback = env->callbacks()->DataDumpRequest;
2722      if (callback != nullptr) {
2723        (*callback)(env->jvmti_external());
2724      }
2725     }
2726   }
2727 }
2728 
2729 void JvmtiExport::post_monitor_contended_enter(JavaThread *thread, ObjectMonitor *obj_mntr) {
2730   oop object = obj_mntr->object();
2731   HandleMark hm(thread);
2732   Handle h(thread, object);
2733 
2734   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2735   if (state == nullptr) {
2736     return;
2737   }
2738   if (thread->is_in_any_VTMS_transition()) {
2739     return; // no events should be posted if thread is in any VTMS transition
2740   }
2741 
2742   EVT_TRIG_TRACE(JVMTI_EVENT_MONITOR_CONTENDED_ENTER,
2743                      ("[%s] monitor contended enter event triggered",
2744                       JvmtiTrace::safe_get_thread_name(thread)));
2745   JvmtiEnvThreadStateIterator it(state);
2746   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2747     if (ets->is_enabled(JVMTI_EVENT_MONITOR_CONTENDED_ENTER)) {
2748       EVT_TRACE(JVMTI_EVENT_MONITOR_CONTENDED_ENTER,
2749                    ("[%s] monitor contended enter event sent",
2750                     JvmtiTrace::safe_get_thread_name(thread)));
2751       JvmtiMonitorEventMark  jem(thread, h());
2752       JvmtiEnv *env = ets->get_env();
2753       JvmtiThreadEventTransition jet(thread);
2754       jvmtiEventMonitorContendedEnter callback = env->callbacks()->MonitorContendedEnter;
2755       if (callback != nullptr) {
2756         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(), jem.jni_object());
2757       }
2758     }
2759   }
2760 }
2761 
2762 void JvmtiExport::post_monitor_contended_entered(JavaThread *thread, ObjectMonitor *obj_mntr) {
2763   oop object = obj_mntr->object();
2764   HandleMark hm(thread);
2765   Handle h(thread, object);
2766 
2767   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2768   if (state == nullptr) {
2769     return;
2770   }
2771   if (thread->is_in_any_VTMS_transition()) {
2772     return; // no events should be posted if thread is in any VTMS transition
2773   }
2774 
2775   EVT_TRIG_TRACE(JVMTI_EVENT_MONITOR_CONTENDED_ENTERED,
2776                      ("[%s] monitor contended entered event triggered",
2777                       JvmtiTrace::safe_get_thread_name(thread)));
2778 
2779   JvmtiEnvThreadStateIterator it(state);
2780   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2781     if (ets->is_enabled(JVMTI_EVENT_MONITOR_CONTENDED_ENTERED)) {
2782       EVT_TRACE(JVMTI_EVENT_MONITOR_CONTENDED_ENTERED,
2783                    ("[%s] monitor contended enter event sent",
2784                     JvmtiTrace::safe_get_thread_name(thread)));
2785       JvmtiMonitorEventMark  jem(thread, h());
2786       JvmtiEnv *env = ets->get_env();
2787       JvmtiThreadEventTransition jet(thread);
2788       jvmtiEventMonitorContendedEntered callback = env->callbacks()->MonitorContendedEntered;
2789       if (callback != nullptr) {
2790         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(), jem.jni_object());
2791       }
2792     }
2793   }
2794 }
2795 
2796 void JvmtiExport::post_monitor_wait(JavaThread *thread, oop object,
2797                                           jlong timeout) {
2798   HandleMark hm(thread);
2799   Handle h(thread, object);
2800 
2801   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2802   if (state == nullptr) {
2803     return;
2804   }
2805   if (thread->is_in_any_VTMS_transition()) {
2806     return; // no events should be posted if thread is in any VTMS transition
2807   }
2808 
2809   EVT_TRIG_TRACE(JVMTI_EVENT_MONITOR_WAIT,
2810                      ("[%s] monitor wait event triggered",
2811                       JvmtiTrace::safe_get_thread_name(thread)));
2812   JvmtiEnvThreadStateIterator it(state);
2813   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2814     if (ets->is_enabled(JVMTI_EVENT_MONITOR_WAIT)) {
2815       EVT_TRACE(JVMTI_EVENT_MONITOR_WAIT,
2816                    ("[%s] monitor wait event sent",
2817                     JvmtiTrace::safe_get_thread_name(thread)));
2818       JvmtiMonitorEventMark  jem(thread, h());
2819       JvmtiEnv *env = ets->get_env();
2820       JvmtiThreadEventTransition jet(thread);
2821       jvmtiEventMonitorWait callback = env->callbacks()->MonitorWait;
2822       if (callback != nullptr) {
2823         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2824                     jem.jni_object(), timeout);
2825       }
2826     }
2827   }
2828 }
2829 
2830 void JvmtiExport::post_monitor_waited(JavaThread *thread, ObjectMonitor *obj_mntr, jboolean timed_out) {
2831   oop object = obj_mntr->object();
2832   HandleMark hm(thread);
2833   Handle h(thread, object);
2834 
2835   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2836   if (state == nullptr) {
2837     return;
2838   }
2839   if (thread->is_in_any_VTMS_transition()) {
2840     return; // no events should be posted if thread is in any VTMS transition
2841   }
2842 
2843   EVT_TRIG_TRACE(JVMTI_EVENT_MONITOR_WAITED,
2844                      ("[%s] monitor waited event triggered",
2845                       JvmtiTrace::safe_get_thread_name(thread)));
2846   JvmtiEnvThreadStateIterator it(state);
2847   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2848     if (ets->is_enabled(JVMTI_EVENT_MONITOR_WAITED)) {
2849       EVT_TRACE(JVMTI_EVENT_MONITOR_WAITED,
2850                    ("[%s] monitor waited event sent",
2851                     JvmtiTrace::safe_get_thread_name(thread)));
2852       JvmtiMonitorEventMark  jem(thread, h());
2853       JvmtiEnv *env = ets->get_env();
2854       JvmtiThreadEventTransition jet(thread);
2855       jvmtiEventMonitorWaited callback = env->callbacks()->MonitorWaited;
2856       if (callback != nullptr) {
2857         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2858                     jem.jni_object(), timed_out);
2859       }
2860     }
2861   }
2862 }
2863 
2864 void JvmtiExport::post_vm_object_alloc(JavaThread *thread, oop object) {
2865   if (object == nullptr) {
2866     return;
2867   }
2868   if (thread->is_in_any_VTMS_transition()) {
2869     return; // no events should be posted if thread is in any VTMS transition
2870   }
2871   HandleMark hm(thread);
2872   Handle h(thread, object);
2873 
2874   EVT_TRIG_TRACE(JVMTI_EVENT_VM_OBJECT_ALLOC, ("[%s] Trg vm object alloc triggered",
2875                       JvmtiTrace::safe_get_thread_name(thread)));
2876   JvmtiEnvIterator it;
2877   for (JvmtiEnv* env = it.first(); env != nullptr; env = it.next(env)) {
2878     if (env->is_enabled(JVMTI_EVENT_VM_OBJECT_ALLOC)) {
2879       EVT_TRACE(JVMTI_EVENT_VM_OBJECT_ALLOC, ("[%s] Evt vmobject alloc sent %s",
2880                                          JvmtiTrace::safe_get_thread_name(thread),
2881                                          object==nullptr? "null" : object->klass()->external_name()));
2882 
2883       JvmtiObjectAllocEventMark jem(thread, h());
2884       JvmtiJavaThreadEventTransition jet(thread);
2885       jvmtiEventVMObjectAlloc callback = env->callbacks()->VMObjectAlloc;
2886       if (callback != nullptr) {
2887         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2888                     jem.jni_jobject(), jem.jni_class(), jem.size());
2889       }
2890     }
2891   }
2892 }
2893 
2894 void JvmtiExport::post_sampled_object_alloc(JavaThread *thread, oop object) {
2895   HandleMark hm(thread);
2896   Handle h(thread, object);
2897 
2898   JvmtiThreadState *state = get_jvmti_thread_state(thread);
2899   if (state == nullptr) {
2900     return;
2901   }
2902   if (object == nullptr) {
2903     return;
2904   }
2905   if (thread->is_in_any_VTMS_transition()) {
2906     return; // no events should be posted if thread is in any VTMS transition
2907   }
2908 
2909   EVT_TRIG_TRACE(JVMTI_EVENT_SAMPLED_OBJECT_ALLOC,
2910                  ("[%s] Trg sampled object alloc triggered",
2911                   JvmtiTrace::safe_get_thread_name(thread)));
2912   JvmtiEnvThreadStateIterator it(state);
2913   for (JvmtiEnvThreadState* ets = it.first(); ets != nullptr; ets = it.next(ets)) {
2914     if (ets->is_enabled(JVMTI_EVENT_SAMPLED_OBJECT_ALLOC)) {
2915       EVT_TRACE(JVMTI_EVENT_SAMPLED_OBJECT_ALLOC,
2916                 ("[%s] Evt sampled object alloc sent %s",
2917                  JvmtiTrace::safe_get_thread_name(thread),
2918                  object == nullptr ? "null" : object->klass()->external_name()));
2919 
2920       JvmtiEnv *env = ets->get_env();
2921       JvmtiObjectAllocEventMark jem(thread, h());
2922       JvmtiJavaThreadEventTransition jet(thread);
2923       jvmtiEventSampledObjectAlloc callback = env->callbacks()->SampledObjectAlloc;
2924       if (callback != nullptr) {
2925         (*callback)(env->jvmti_external(), jem.jni_env(), jem.jni_thread(),
2926                     jem.jni_jobject(), jem.jni_class(), jem.size());
2927       }
2928     }
2929   }
2930 }
2931 
2932 ////////////////////////////////////////////////////////////////////////////////////////////////
2933 
2934 void JvmtiExport::cleanup_thread(JavaThread* thread) {
2935   assert(JavaThread::current() == thread, "thread is not current");
2936   MutexLocker mu(thread, JvmtiThreadState_lock);
2937 
2938   if (thread->jvmti_thread_state() != nullptr) {
2939     // This has to happen after the thread state is removed, which is
2940     // why it is not in post_thread_end_event like its complement
2941     // Maybe both these functions should be rolled into the posts?
2942     JvmtiEventController::thread_ended(thread);
2943   }
2944 }
2945 
2946 void JvmtiExport::clear_detected_exception(JavaThread* thread) {
2947   assert(JavaThread::current() == thread, "thread is not current");
2948 
2949   JvmtiThreadState* state = thread->jvmti_thread_state();
2950   if (state != nullptr) {
2951     state->clear_exception_state();
2952   }
2953 }
2954 
2955 // Onload raw monitor transition.
2956 void JvmtiExport::transition_pending_onload_raw_monitors() {
2957   JvmtiPendingMonitors::transition_raw_monitors();
2958 }
2959 
2960 // Setup current current thread for event collection.
2961 void JvmtiEventCollector::setup_jvmti_thread_state() {
2962   // set this event collector to be the current one.
2963   JvmtiThreadState* state = JvmtiThreadState::state_for(JavaThread::current());
2964   // state can only be null if the current thread is exiting which
2965   // should not happen since we're trying to configure for event collection
2966   guarantee(state != nullptr, "exiting thread called setup_jvmti_thread_state");
2967   if (is_vm_object_alloc_event()) {
2968     JvmtiVMObjectAllocEventCollector *prev = state->get_vm_object_alloc_event_collector();
2969 
2970     // If we have a previous collector and it is disabled, it means this allocation came from a
2971     // callback induced VM Object allocation, do not register this collector then.
2972     if (prev && !prev->is_enabled()) {
2973       return;
2974     }
2975     _prev = prev;
2976     state->set_vm_object_alloc_event_collector((JvmtiVMObjectAllocEventCollector *)this);
2977   } else if (is_dynamic_code_event()) {
2978     _prev = state->get_dynamic_code_event_collector();
2979     state->set_dynamic_code_event_collector((JvmtiDynamicCodeEventCollector *)this);
2980   } else if (is_sampled_object_alloc_event()) {
2981     JvmtiSampledObjectAllocEventCollector *prev = state->get_sampled_object_alloc_event_collector();
2982 
2983     if (prev) {
2984       // JvmtiSampledObjectAllocEventCollector wants only one active collector
2985       // enabled. This allows to have a collector detect a user code requiring
2986       // a sample in the callback.
2987       return;
2988     }
2989     state->set_sampled_object_alloc_event_collector((JvmtiSampledObjectAllocEventCollector*) this);
2990   }
2991 
2992   _unset_jvmti_thread_state = true;
2993 }
2994 
2995 // Unset current event collection in this thread and reset it with previous
2996 // collector.
2997 void JvmtiEventCollector::unset_jvmti_thread_state() {
2998   if (!_unset_jvmti_thread_state) {
2999     return;
3000   }
3001 
3002   JvmtiThreadState* state = JavaThread::current()->jvmti_thread_state();
3003   if (state != nullptr) {
3004     // restore the previous event collector (if any)
3005     if (is_vm_object_alloc_event()) {
3006       if (state->get_vm_object_alloc_event_collector() == this) {
3007         state->set_vm_object_alloc_event_collector((JvmtiVMObjectAllocEventCollector *)_prev);
3008       } else {
3009         // this thread's jvmti state was created during the scope of
3010         // the event collector.
3011       }
3012     } else if (is_dynamic_code_event()) {
3013       if (state->get_dynamic_code_event_collector() == this) {
3014         state->set_dynamic_code_event_collector((JvmtiDynamicCodeEventCollector *)_prev);
3015       } else {
3016         // this thread's jvmti state was created during the scope of
3017         // the event collector.
3018       }
3019     } else if (is_sampled_object_alloc_event()) {
3020       if (state->get_sampled_object_alloc_event_collector() == this) {
3021         state->set_sampled_object_alloc_event_collector((JvmtiSampledObjectAllocEventCollector*)_prev);
3022       } else {
3023         // this thread's jvmti state was created during the scope of
3024         // the event collector.
3025       }
3026     }
3027   }
3028 }
3029 
3030 // create the dynamic code event collector
3031 JvmtiDynamicCodeEventCollector::JvmtiDynamicCodeEventCollector() : _code_blobs(nullptr) {
3032   if (JvmtiExport::should_post_dynamic_code_generated()) {
3033     setup_jvmti_thread_state();
3034   }
3035 }
3036 
3037 // iterate over any code blob descriptors collected and post a
3038 // DYNAMIC_CODE_GENERATED event to the profiler.
3039 JvmtiDynamicCodeEventCollector::~JvmtiDynamicCodeEventCollector() {
3040   assert(!JavaThread::current()->owns_locks(), "all locks must be released to post deferred events");
3041  // iterate over any code blob descriptors that we collected
3042  if (_code_blobs != nullptr) {
3043    for (int i=0; i<_code_blobs->length(); i++) {
3044      JvmtiCodeBlobDesc* blob = _code_blobs->at(i);
3045      JvmtiExport::post_dynamic_code_generated(blob->name(), blob->code_begin(), blob->code_end());
3046      FreeHeap(blob);
3047    }
3048    delete _code_blobs;
3049  }
3050  unset_jvmti_thread_state();
3051 }
3052 
3053 // register a stub
3054 void JvmtiDynamicCodeEventCollector::register_stub(const char* name, address start, address end) {
3055  if (_code_blobs == nullptr) {
3056    _code_blobs = new (mtServiceability) GrowableArray<JvmtiCodeBlobDesc*>(1, mtServiceability);
3057  }
3058  _code_blobs->append(new JvmtiCodeBlobDesc(name, start, end));
3059 }
3060 
3061 // Setup current thread to record vm allocated objects.
3062 JvmtiObjectAllocEventCollector::JvmtiObjectAllocEventCollector() :
3063     _allocated(nullptr), _enable(false), _post_callback(nullptr) {
3064 }
3065 
3066 // Post vm_object_alloc event for vm allocated objects visible to java
3067 // world.
3068 void JvmtiObjectAllocEventCollector::generate_call_for_allocated() {
3069   if (_allocated) {
3070     set_enabled(false);
3071     for (int i = 0; i < _allocated->length(); i++) {
3072       oop obj = _allocated->at(i).resolve();
3073       _post_callback(JavaThread::current(), obj);
3074       // Release OopHandle
3075       _allocated->at(i).release(JvmtiExport::jvmti_oop_storage());
3076 
3077     }
3078     delete _allocated, _allocated = nullptr;
3079   }
3080 }
3081 
3082 void JvmtiObjectAllocEventCollector::record_allocation(oop obj) {
3083   assert(is_enabled(), "Object alloc event collector is not enabled");
3084   if (_allocated == nullptr) {
3085     _allocated = new (mtServiceability) GrowableArray<OopHandle>(1, mtServiceability);
3086   }
3087   _allocated->push(OopHandle(JvmtiExport::jvmti_oop_storage(), obj));
3088 }
3089 
3090 // Disable collection of VMObjectAlloc events
3091 NoJvmtiVMObjectAllocMark::NoJvmtiVMObjectAllocMark() : _collector(nullptr) {
3092   // a no-op if VMObjectAlloc event is not enabled
3093   if (!JvmtiExport::should_post_vm_object_alloc()) {
3094     return;
3095   }
3096   Thread* thread = Thread::current_or_null();
3097   if (thread != nullptr && thread->is_Java_thread())  {
3098     JavaThread* current_thread = JavaThread::cast(thread);
3099     JvmtiThreadState *state = current_thread->jvmti_thread_state();
3100     if (state != nullptr) {
3101       JvmtiVMObjectAllocEventCollector *collector;
3102       collector = state->get_vm_object_alloc_event_collector();
3103       if (collector != nullptr && collector->is_enabled()) {
3104         _collector = collector;
3105         _collector->set_enabled(false);
3106       }
3107     }
3108   }
3109 }
3110 
3111 // Re-Enable collection of VMObjectAlloc events (if previously enabled)
3112 NoJvmtiVMObjectAllocMark::~NoJvmtiVMObjectAllocMark() {
3113   if (was_enabled()) {
3114     _collector->set_enabled(true);
3115   }
3116 };
3117 
3118 // Setup current thread to record vm allocated objects.
3119 JvmtiVMObjectAllocEventCollector::JvmtiVMObjectAllocEventCollector() {
3120   if (JvmtiExport::should_post_vm_object_alloc()) {
3121     _enable = true;
3122     setup_jvmti_thread_state();
3123     _post_callback = JvmtiExport::post_vm_object_alloc;
3124   }
3125 }
3126 
3127 JvmtiVMObjectAllocEventCollector::~JvmtiVMObjectAllocEventCollector() {
3128   if (_enable) {
3129     generate_call_for_allocated();
3130   }
3131   unset_jvmti_thread_state();
3132 }
3133 
3134 bool JvmtiSampledObjectAllocEventCollector::object_alloc_is_safe_to_sample() {
3135   Thread* thread = Thread::current();
3136   // Really only sample allocations if this is a JavaThread and not the compiler
3137   // thread.
3138   if (!thread->is_Java_thread() || thread->is_Compiler_thread()) {
3139     return false;
3140   }
3141 
3142   if (MultiArray_lock->owner() == thread) {
3143     return false;
3144   }
3145   return true;
3146 }
3147 
3148 // Setup current thread to record sampled allocated objects.
3149 void JvmtiSampledObjectAllocEventCollector::start() {
3150   if (JvmtiExport::should_post_sampled_object_alloc()) {
3151     if (!object_alloc_is_safe_to_sample()) {
3152       return;
3153     }
3154 
3155     _enable = true;
3156     setup_jvmti_thread_state();
3157     _post_callback = JvmtiExport::post_sampled_object_alloc;
3158   }
3159 }
3160 
3161 JvmtiSampledObjectAllocEventCollector::~JvmtiSampledObjectAllocEventCollector() {
3162   if (!_enable) {
3163     return;
3164   }
3165 
3166   generate_call_for_allocated();
3167   unset_jvmti_thread_state();
3168 
3169   // Unset the sampling collector as present in assertion mode only.
3170   assert(Thread::current()->is_Java_thread(),
3171          "Should always be in a Java thread");
3172 }
3173 
3174 JvmtiGCMarker::JvmtiGCMarker() {
3175   // if there aren't any JVMTI environments then nothing to do
3176   if (!JvmtiEnv::environments_might_exist()) {
3177     return;
3178   }
3179 
3180   if (JvmtiExport::should_post_garbage_collection_start()) {
3181     JvmtiExport::post_garbage_collection_start();
3182   }
3183 
3184   if (SafepointSynchronize::is_at_safepoint()) {
3185     // Do clean up tasks that need to be done at a safepoint
3186     JvmtiEnvBase::check_for_periodic_clean_up();
3187   }
3188 }
3189 
3190 JvmtiGCMarker::~JvmtiGCMarker() {
3191   // if there aren't any JVMTI environments then nothing to do
3192   if (!JvmtiEnv::environments_might_exist()) {
3193     return;
3194   }
3195 
3196   // JVMTI notify gc finish
3197   if (JvmtiExport::should_post_garbage_collection_finish()) {
3198     JvmtiExport::post_garbage_collection_finish();
3199   }
3200 }