1 /*
   2  * Copyright 2003-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_jvmtiEventController.cpp.incl"
  27 
  28 #ifdef JVMTI_TRACE
  29 #define EC_TRACE(out) if (JvmtiTrace::trace_event_controller()) { SafeResourceMark rm; tty->print_cr out; } while (0)
  30 #else
  31 #define EC_TRACE(out)
  32 #endif /*JVMTI_TRACE */
  33 
  34 // bits for standard events
  35 
  36 static const jlong  SINGLE_STEP_BIT = (((jlong)1) << (JVMTI_EVENT_SINGLE_STEP - TOTAL_MIN_EVENT_TYPE_VAL));
  37 static const jlong  FRAME_POP_BIT = (((jlong)1) << (JVMTI_EVENT_FRAME_POP - TOTAL_MIN_EVENT_TYPE_VAL));
  38 static const jlong  BREAKPOINT_BIT = (((jlong)1) << (JVMTI_EVENT_BREAKPOINT - TOTAL_MIN_EVENT_TYPE_VAL));
  39 static const jlong  FIELD_ACCESS_BIT = (((jlong)1) << (JVMTI_EVENT_FIELD_ACCESS - TOTAL_MIN_EVENT_TYPE_VAL));
  40 static const jlong  FIELD_MODIFICATION_BIT = (((jlong)1) << (JVMTI_EVENT_FIELD_MODIFICATION - TOTAL_MIN_EVENT_TYPE_VAL));
  41 static const jlong  METHOD_ENTRY_BIT = (((jlong)1) << (JVMTI_EVENT_METHOD_ENTRY - TOTAL_MIN_EVENT_TYPE_VAL));
  42 static const jlong  METHOD_EXIT_BIT = (((jlong)1) << (JVMTI_EVENT_METHOD_EXIT - TOTAL_MIN_EVENT_TYPE_VAL));
  43 static const jlong  CLASS_FILE_LOAD_HOOK_BIT = (((jlong)1) << (JVMTI_EVENT_CLASS_FILE_LOAD_HOOK - TOTAL_MIN_EVENT_TYPE_VAL));
  44 static const jlong  NATIVE_METHOD_BIND_BIT = (((jlong)1) << (JVMTI_EVENT_NATIVE_METHOD_BIND - TOTAL_MIN_EVENT_TYPE_VAL));
  45 static const jlong  VM_START_BIT = (((jlong)1) << (JVMTI_EVENT_VM_START - TOTAL_MIN_EVENT_TYPE_VAL));
  46 static const jlong  VM_INIT_BIT = (((jlong)1) << (JVMTI_EVENT_VM_INIT - TOTAL_MIN_EVENT_TYPE_VAL));
  47 static const jlong  VM_DEATH_BIT = (((jlong)1) << (JVMTI_EVENT_VM_DEATH - TOTAL_MIN_EVENT_TYPE_VAL));
  48 static const jlong  CLASS_LOAD_BIT = (((jlong)1) << (JVMTI_EVENT_CLASS_LOAD - TOTAL_MIN_EVENT_TYPE_VAL));
  49 static const jlong  CLASS_PREPARE_BIT = (((jlong)1) << (JVMTI_EVENT_CLASS_PREPARE - TOTAL_MIN_EVENT_TYPE_VAL));
  50 static const jlong  THREAD_START_BIT = (((jlong)1) << (JVMTI_EVENT_THREAD_START - TOTAL_MIN_EVENT_TYPE_VAL));
  51 static const jlong  THREAD_END_BIT = (((jlong)1) << (JVMTI_EVENT_THREAD_END - TOTAL_MIN_EVENT_TYPE_VAL));
  52 static const jlong  EXCEPTION_THROW_BIT = (((jlong)1) << (JVMTI_EVENT_EXCEPTION - TOTAL_MIN_EVENT_TYPE_VAL));
  53 static const jlong  EXCEPTION_CATCH_BIT = (((jlong)1) << (JVMTI_EVENT_EXCEPTION_CATCH - TOTAL_MIN_EVENT_TYPE_VAL));
  54 static const jlong  MONITOR_CONTENDED_ENTER_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_CONTENDED_ENTER - TOTAL_MIN_EVENT_TYPE_VAL));
  55 static const jlong  MONITOR_CONTENDED_ENTERED_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_CONTENDED_ENTERED - TOTAL_MIN_EVENT_TYPE_VAL));
  56 static const jlong  MONITOR_WAIT_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_WAIT - TOTAL_MIN_EVENT_TYPE_VAL));
  57 static const jlong  MONITOR_WAITED_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_WAITED - TOTAL_MIN_EVENT_TYPE_VAL));
  58 static const jlong  DYNAMIC_CODE_GENERATED_BIT = (((jlong)1) << (JVMTI_EVENT_DYNAMIC_CODE_GENERATED - TOTAL_MIN_EVENT_TYPE_VAL));
  59 static const jlong  DATA_DUMP_BIT = (((jlong)1) << (JVMTI_EVENT_DATA_DUMP_REQUEST - TOTAL_MIN_EVENT_TYPE_VAL));
  60 static const jlong  COMPILED_METHOD_LOAD_BIT = (((jlong)1) << (JVMTI_EVENT_COMPILED_METHOD_LOAD - TOTAL_MIN_EVENT_TYPE_VAL));
  61 static const jlong  COMPILED_METHOD_UNLOAD_BIT = (((jlong)1) << (JVMTI_EVENT_COMPILED_METHOD_UNLOAD - TOTAL_MIN_EVENT_TYPE_VAL));
  62 static const jlong  GARBAGE_COLLECTION_START_BIT = (((jlong)1) << (JVMTI_EVENT_GARBAGE_COLLECTION_START - TOTAL_MIN_EVENT_TYPE_VAL));
  63 static const jlong  GARBAGE_COLLECTION_FINISH_BIT = (((jlong)1) << (JVMTI_EVENT_GARBAGE_COLLECTION_FINISH - TOTAL_MIN_EVENT_TYPE_VAL));
  64 static const jlong  OBJECT_FREE_BIT = (((jlong)1) << (JVMTI_EVENT_OBJECT_FREE - TOTAL_MIN_EVENT_TYPE_VAL));
  65 static const jlong  RESOURCE_EXHAUSTED_BIT = (((jlong)1) << (JVMTI_EVENT_RESOURCE_EXHAUSTED - TOTAL_MIN_EVENT_TYPE_VAL));
  66 static const jlong  VM_OBJECT_ALLOC_BIT = (((jlong)1) << (JVMTI_EVENT_VM_OBJECT_ALLOC - TOTAL_MIN_EVENT_TYPE_VAL));
  67 
  68 // bits for extension events
  69 static const jlong  CLASS_UNLOAD_BIT = (((jlong)1) << (EXT_EVENT_CLASS_UNLOAD - TOTAL_MIN_EVENT_TYPE_VAL));
  70 
  71 
  72 static const jlong  MONITOR_BITS = MONITOR_CONTENDED_ENTER_BIT | MONITOR_CONTENDED_ENTERED_BIT |
  73                           MONITOR_WAIT_BIT | MONITOR_WAITED_BIT;
  74 static const jlong  EXCEPTION_BITS = EXCEPTION_THROW_BIT | EXCEPTION_CATCH_BIT;
  75 static const jlong  INTERP_EVENT_BITS =  SINGLE_STEP_BIT | METHOD_ENTRY_BIT | METHOD_EXIT_BIT |
  76                                 FRAME_POP_BIT | FIELD_ACCESS_BIT | FIELD_MODIFICATION_BIT;
  77 static const jlong  THREAD_FILTERED_EVENT_BITS = INTERP_EVENT_BITS | EXCEPTION_BITS | MONITOR_BITS |
  78                                         BREAKPOINT_BIT | CLASS_LOAD_BIT | CLASS_PREPARE_BIT | THREAD_END_BIT;
  79 static const jlong  NEED_THREAD_LIFE_EVENTS = THREAD_FILTERED_EVENT_BITS | THREAD_START_BIT;
  80 static const jlong  EARLY_EVENT_BITS = CLASS_FILE_LOAD_HOOK_BIT |
  81                                VM_START_BIT | VM_INIT_BIT | VM_DEATH_BIT | NATIVE_METHOD_BIND_BIT |
  82                                THREAD_START_BIT | THREAD_END_BIT |
  83                                DYNAMIC_CODE_GENERATED_BIT;
  84 static const jlong  GLOBAL_EVENT_BITS = ~THREAD_FILTERED_EVENT_BITS;
  85 static const jlong  SHOULD_POST_ON_EXCEPTIONS_BITS = EXCEPTION_BITS | METHOD_EXIT_BIT | FRAME_POP_BIT;
  86 
  87 ///////////////////////////////////////////////////////////////
  88 //
  89 // JvmtiEventEnabled
  90 //
  91 
  92 JvmtiEventEnabled::JvmtiEventEnabled() {
  93   clear();
  94 }
  95 
  96 
  97 void JvmtiEventEnabled::clear() {
  98   _enabled_bits = 0;
  99 #ifndef PRODUCT
 100   _init_guard = JEE_INIT_GUARD;
 101 #endif
 102 }
 103 
 104 void JvmtiEventEnabled::set_enabled(jvmtiEvent event_type, bool enabled) {
 105   jlong bits = get_bits();
 106   jlong mask = bit_for(event_type);
 107   if (enabled) {
 108     bits |= mask;
 109   } else {
 110     bits &= ~mask;
 111   }
 112   set_bits(bits);
 113 }
 114 
 115 
 116 ///////////////////////////////////////////////////////////////
 117 //
 118 // JvmtiEnvThreadEventEnable
 119 //
 120 
 121 JvmtiEnvThreadEventEnable::JvmtiEnvThreadEventEnable() {
 122   _event_user_enabled.clear();
 123   _event_enabled.clear();
 124 }
 125 
 126 
 127 JvmtiEnvThreadEventEnable::~JvmtiEnvThreadEventEnable() {
 128   _event_user_enabled.clear();
 129   _event_enabled.clear();
 130 }
 131 
 132 
 133 ///////////////////////////////////////////////////////////////
 134 //
 135 // JvmtiThreadEventEnable
 136 //
 137 
 138 JvmtiThreadEventEnable::JvmtiThreadEventEnable() {
 139   _event_enabled.clear();
 140 }
 141 
 142 
 143 JvmtiThreadEventEnable::~JvmtiThreadEventEnable() {
 144   _event_enabled.clear();
 145 }
 146 
 147 
 148 ///////////////////////////////////////////////////////////////
 149 //
 150 // JvmtiEnvEventEnable
 151 //
 152 
 153 JvmtiEnvEventEnable::JvmtiEnvEventEnable() {
 154   _event_user_enabled.clear();
 155   _event_callback_enabled.clear();
 156   _event_enabled.clear();
 157 }
 158 
 159 
 160 JvmtiEnvEventEnable::~JvmtiEnvEventEnable() {
 161   _event_user_enabled.clear();
 162   _event_callback_enabled.clear();
 163   _event_enabled.clear();
 164 }
 165 
 166 
 167 ///////////////////////////////////////////////////////////////
 168 //
 169 // VM_EnterInterpOnlyMode
 170 //
 171 
 172 class VM_EnterInterpOnlyMode : public VM_Operation {
 173 private:
 174   JvmtiThreadState *_state;
 175 
 176 public:
 177   VM_EnterInterpOnlyMode(JvmtiThreadState *state);
 178 
 179   bool allow_nested_vm_operations() const        { return true; }
 180   VMOp_Type type() const { return VMOp_EnterInterpOnlyMode; }
 181   void doit();
 182 
 183   // to do: this same function is in jvmtiImpl - should be in one place
 184   bool can_be_deoptimized(vframe* vf) {
 185     return (vf->is_compiled_frame() && vf->fr().can_be_deoptimized());
 186   }
 187 };
 188 
 189 VM_EnterInterpOnlyMode::VM_EnterInterpOnlyMode(JvmtiThreadState *state)
 190   : _state(state)
 191 {
 192 }
 193 
 194 
 195 void VM_EnterInterpOnlyMode::doit() {
 196   // Set up the current stack depth for later tracking
 197   _state->invalidate_cur_stack_depth();
 198 
 199   _state->enter_interp_only_mode();
 200 
 201   JavaThread *thread = _state->get_thread();
 202   if (thread->has_last_Java_frame()) {
 203     // If running in fullspeed mode, single stepping is implemented
 204     // as follows: first, the interpreter does not dispatch to
 205     // compiled code for threads that have single stepping enabled;
 206     // second, we deoptimize all methods on the thread's stack when
 207     // interpreted-only mode is enabled the first time for a given
 208     // thread (nothing to do if no Java frames yet).
 209     int num_marked = 0;
 210     ResourceMark resMark;
 211     RegisterMap rm(thread, false);
 212     for (vframe* vf = thread->last_java_vframe(&rm); vf; vf = vf->sender()) {
 213       if (can_be_deoptimized(vf)) {
 214         ((compiledVFrame*) vf)->code()->mark_for_deoptimization();
 215         ++num_marked;
 216       }
 217     }
 218     if (num_marked > 0) {
 219       VM_Deoptimize op;
 220       VMThread::execute(&op);
 221     }
 222   }
 223 }
 224 
 225 
 226 ///////////////////////////////////////////////////////////////
 227 //
 228 // VM_ChangeSingleStep
 229 //
 230 
 231 class VM_ChangeSingleStep : public VM_Operation {
 232 private:
 233   bool _on;
 234 
 235 public:
 236   VM_ChangeSingleStep(bool on);
 237   VMOp_Type type() const                         { return VMOp_ChangeSingleStep; }
 238   bool allow_nested_vm_operations() const        { return true; }
 239   void doit();   // method definition is after definition of JvmtiEventControllerPrivate because of scoping
 240 };
 241 
 242 
 243 VM_ChangeSingleStep::VM_ChangeSingleStep(bool on)
 244   : _on(on != 0)
 245 {
 246 }
 247 
 248 
 249 
 250 
 251 ///////////////////////////////////////////////////////////////
 252 //
 253 // JvmtiEventControllerPrivate
 254 //
 255 // Private internal implementation methods for JvmtiEventController.
 256 //
 257 // These methods are thread safe either because they are called
 258 // in early VM initialization which is single threaded, or they
 259 // hold the JvmtiThreadState_lock.
 260 //
 261 
 262 class JvmtiEventControllerPrivate : public AllStatic {
 263   static bool _initialized;
 264 public:
 265   static void set_should_post_single_step(bool on);
 266   static void enter_interp_only_mode(JvmtiThreadState *state);
 267   static void leave_interp_only_mode(JvmtiThreadState *state);
 268   static void recompute_enabled();
 269   static jlong recompute_env_enabled(JvmtiEnvBase* env);
 270   static jlong recompute_env_thread_enabled(JvmtiEnvThreadState* ets, JvmtiThreadState* state);
 271   static jlong recompute_thread_enabled(JvmtiThreadState *state);
 272   static void event_init();
 273 
 274   static void set_user_enabled(JvmtiEnvBase *env, JavaThread *thread,
 275                         jvmtiEvent event_type, bool enabled);
 276   static void set_event_callbacks(JvmtiEnvBase *env,
 277                                   const jvmtiEventCallbacks* callbacks,
 278                                   jint size_of_callbacks);
 279 
 280   static void set_extension_event_callback(JvmtiEnvBase *env,
 281                                            jint extension_event_index,
 282                                            jvmtiExtensionEvent callback);
 283 
 284   static void set_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
 285   static void clear_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
 286   static void clear_to_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
 287   static void change_field_watch(jvmtiEvent event_type, bool added);
 288 
 289   static void thread_started(JavaThread *thread);
 290   static void thread_ended(JavaThread *thread);
 291 
 292   static void env_initialize(JvmtiEnvBase *env);
 293   static void env_dispose(JvmtiEnvBase *env);
 294 
 295   static void vm_start();
 296   static void vm_init();
 297   static void vm_death();
 298 
 299   static void trace_changed(JvmtiThreadState *state, jlong now_enabled, jlong changed);
 300   static void trace_changed(jlong now_enabled, jlong changed);
 301 };
 302 
 303 bool JvmtiEventControllerPrivate::_initialized = false;
 304 
 305 void JvmtiEventControllerPrivate::set_should_post_single_step(bool on) {
 306   // we have permission to do this, VM op doesn't
 307   JvmtiExport::set_should_post_single_step(on);
 308 }
 309 
 310 
 311 // This change must always be occur when at a safepoint.
 312 // Being at a safepoint causes the interpreter to use the
 313 // safepoint dispatch table which we overload to find single
 314 // step points.  Just to be sure that it has been set, we
 315 // call notice_safepoints when turning on single stepping.
 316 // When we leave our current safepoint, should_post_single_step
 317 // will be checked by the interpreter, and the table kept
 318 // or changed accordingly.
 319 void VM_ChangeSingleStep::doit() {
 320   JvmtiEventControllerPrivate::set_should_post_single_step(_on);
 321   if (_on) {
 322     Interpreter::notice_safepoints();
 323   }
 324 }
 325 
 326 
 327 void JvmtiEventControllerPrivate::enter_interp_only_mode(JvmtiThreadState *state) {
 328   EC_TRACE(("JVMTI [%s] # Entering interpreter only mode",
 329             JvmtiTrace::safe_get_thread_name(state->get_thread())));
 330 
 331   VM_EnterInterpOnlyMode op(state);
 332   VMThread::execute(&op);
 333 }
 334 
 335 
 336 void
 337 JvmtiEventControllerPrivate::leave_interp_only_mode(JvmtiThreadState *state) {
 338   EC_TRACE(("JVMTI [%s] # Leaving interpreter only mode",
 339             JvmtiTrace::safe_get_thread_name(state->get_thread())));
 340   state->leave_interp_only_mode();
 341 }
 342 
 343 
 344 void
 345 JvmtiEventControllerPrivate::trace_changed(JvmtiThreadState *state, jlong now_enabled, jlong changed) {
 346 #ifdef JVMTI_TRACE
 347   if (JvmtiTrace::trace_event_controller()) {
 348     SafeResourceMark rm;
 349     // traces standard events only
 350     for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
 351       jlong bit = JvmtiEventEnabled::bit_for((jvmtiEvent)ei);
 352       if (changed & bit) {
 353         // it changed, print it
 354         tty->print_cr("JVMTI [%s] # %s event %s",
 355                       JvmtiTrace::safe_get_thread_name(state->get_thread()),
 356                       (now_enabled & bit)? "Enabling" : "Disabling", JvmtiTrace::event_name((jvmtiEvent)ei));
 357       }
 358     }
 359   }
 360 #endif /*JVMTI_TRACE */
 361 }
 362 
 363 
 364 void
 365 JvmtiEventControllerPrivate::trace_changed(jlong now_enabled, jlong changed) {
 366 #ifdef JVMTI_TRACE
 367   if (JvmtiTrace::trace_event_controller()) {
 368     SafeResourceMark rm;
 369     // traces standard events only
 370     for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
 371       jlong bit = JvmtiEventEnabled::bit_for((jvmtiEvent)ei);
 372       if (changed & bit) {
 373         // it changed, print it
 374         tty->print_cr("JVMTI [-] # %s event %s",
 375                       (now_enabled & bit)? "Enabling" : "Disabling", JvmtiTrace::event_name((jvmtiEvent)ei));
 376       }
 377     }
 378   }
 379 #endif /*JVMTI_TRACE */
 380 }
 381 
 382 
 383 // For the specified env: compute the currently truly enabled events
 384 // set external state accordingly.
 385 // Return value and set value must include all events.
 386 // But outside this class, only non-thread-filtered events can be queried..
 387 jlong
 388 JvmtiEventControllerPrivate::recompute_env_enabled(JvmtiEnvBase* env) {
 389   jlong was_enabled = env->env_event_enable()->_event_enabled.get_bits();
 390   jlong now_enabled =
 391     env->env_event_enable()->_event_callback_enabled.get_bits() &
 392     env->env_event_enable()->_event_user_enabled.get_bits();
 393 
 394   switch (JvmtiEnv::get_phase()) {
 395   case JVMTI_PHASE_PRIMORDIAL:
 396   case JVMTI_PHASE_ONLOAD:
 397     // only these events allowed in primordial or onload phase
 398     now_enabled &= (EARLY_EVENT_BITS & ~THREAD_FILTERED_EVENT_BITS);
 399     break;
 400   case JVMTI_PHASE_START:
 401     // only these events allowed in start phase
 402     now_enabled &= EARLY_EVENT_BITS;
 403     break;
 404   case JVMTI_PHASE_LIVE:
 405     // all events allowed during live phase
 406     break;
 407   case JVMTI_PHASE_DEAD:
 408     // no events allowed when dead
 409     now_enabled = 0;
 410     break;
 411   default:
 412     assert(false, "no other phases - sanity check");
 413     break;
 414   }
 415 
 416   // will we really send these events to this env
 417   env->env_event_enable()->_event_enabled.set_bits(now_enabled);
 418 
 419   trace_changed(now_enabled, (now_enabled ^ was_enabled)  & ~THREAD_FILTERED_EVENT_BITS);
 420 
 421   return now_enabled;
 422 }
 423 
 424 
 425 // For the specified env and thread: compute the currently truly enabled events
 426 // set external state accordingly.  Only thread-filtered events are included.
 427 jlong
 428 JvmtiEventControllerPrivate::recompute_env_thread_enabled(JvmtiEnvThreadState* ets, JvmtiThreadState* state) {
 429   JvmtiEnv *env = ets->get_env();
 430 
 431   jlong was_enabled = ets->event_enable()->_event_enabled.get_bits();
 432   jlong now_enabled =  THREAD_FILTERED_EVENT_BITS &
 433     env->env_event_enable()->_event_callback_enabled.get_bits() &
 434     (env->env_event_enable()->_event_user_enabled.get_bits() |
 435      ets->event_enable()->_event_user_enabled.get_bits());
 436 
 437   // for frame pops and field watchs, computed enabled state
 438   // is only true if an event has been requested
 439   if (!ets->has_frame_pops()) {
 440     now_enabled &= ~FRAME_POP_BIT;
 441   }
 442   if (*((int *)JvmtiExport::get_field_access_count_addr()) == 0) {
 443     now_enabled &= ~FIELD_ACCESS_BIT;
 444   }
 445   if (*((int *)JvmtiExport::get_field_modification_count_addr()) == 0) {
 446     now_enabled &= ~FIELD_MODIFICATION_BIT;
 447   }
 448 
 449   switch (JvmtiEnv::get_phase()) {
 450   case JVMTI_PHASE_DEAD:
 451     // no events allowed when dead
 452     now_enabled = 0;
 453     break;
 454   }
 455 
 456   // if anything changed do update
 457   if (now_enabled != was_enabled) {
 458 
 459     // will we really send these events to this thread x env
 460     ets->event_enable()->_event_enabled.set_bits(now_enabled);
 461 
 462     // If the enabled status of the single step or breakpoint events changed,
 463     // the location status may need to change as well.
 464     jlong changed = now_enabled ^ was_enabled;
 465     if (changed & SINGLE_STEP_BIT) {
 466       ets->reset_current_location(JVMTI_EVENT_SINGLE_STEP, (now_enabled & SINGLE_STEP_BIT) != 0);
 467     }
 468     if (changed & BREAKPOINT_BIT) {
 469       ets->reset_current_location(JVMTI_EVENT_BREAKPOINT,  (now_enabled & BREAKPOINT_BIT) != 0);
 470     }
 471     trace_changed(state, now_enabled, changed);
 472   }
 473   return now_enabled;
 474 }
 475 
 476 
 477 // For the specified thread: compute the currently truly enabled events
 478 // set external state accordingly.  Only thread-filtered events are included.
 479 jlong
 480 JvmtiEventControllerPrivate::recompute_thread_enabled(JvmtiThreadState *state) {
 481   if (state == NULL) {
 482     // associated JavaThread is exiting
 483     return (jlong)0;
 484   }
 485 
 486   jlong was_any_env_enabled = state->thread_event_enable()->_event_enabled.get_bits();
 487   jlong any_env_enabled = 0;
 488 
 489   {
 490     // This iteration will include JvmtiEnvThreadStates whoses environments
 491     // have been disposed.  These JvmtiEnvThreadStates must not be filtered
 492     // as recompute must be called on them to disable their events,
 493     JvmtiEnvThreadStateIterator it(state);
 494     for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {
 495       any_env_enabled |= recompute_env_thread_enabled(ets, state);
 496     }
 497   }
 498 
 499   if (any_env_enabled != was_any_env_enabled) {
 500     // mark if event is truly enabled on this thread in any environment
 501     state->thread_event_enable()->_event_enabled.set_bits(any_env_enabled);
 502 
 503     // compute interp_only mode
 504     bool should_be_interp = (any_env_enabled & INTERP_EVENT_BITS) != 0;
 505     bool is_now_interp = state->is_interp_only_mode();
 506 
 507     if (should_be_interp != is_now_interp) {
 508       if (should_be_interp) {
 509         enter_interp_only_mode(state);
 510       } else {
 511         leave_interp_only_mode(state);
 512       }
 513     }
 514     
 515     // update the JavaThread cached value for thread-specific should_post_on_exceptions value
 516     JavaThread *jthread = state->get_thread();
 517     jthread->set_should_post_on_exceptions_flag((any_env_enabled & SHOULD_POST_ON_EXCEPTIONS_BITS) ? JNI_TRUE : JNI_FALSE);
 518   }
 519 
 520   return any_env_enabled;
 521 }
 522 
 523 
 524 // Compute truly enabled events - meaning if the event can and could be
 525 // sent.  An event is truly enabled if it is user enabled on the thread
 526 // or globally user enabled, but only if there is a callback or event hook
 527 // for it and, for field watch and frame pop, one has been set.
 528 // Compute if truly enabled, per thread, per environment, per combination
 529 // (thread x environment), and overall.  These merges are true if any is true.
 530 // True per thread if some environment has callback set and the event is globally
 531 // enabled or enabled for this thread.
 532 // True per environment if the callback is set and the event is globally
 533 // enabled in this environment or enabled for any thread in this environment.
 534 // True per combination if the environment has the callback set and the
 535 // event is globally enabled in this environment or the event is enabled
 536 // for this thread and environment.
 537 //
 538 // All states transitions dependent on these transitions are also handled here.
 539 void
 540 JvmtiEventControllerPrivate::recompute_enabled() {
 541   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
 542 
 543   // event enabled for any thread in any environment
 544   jlong was_any_env_thread_enabled = JvmtiEventController::_universal_global_event_enabled.get_bits();
 545   jlong any_env_thread_enabled = 0;
 546 
 547   EC_TRACE(("JVMTI [-] # recompute enabled - before %llx", was_any_env_thread_enabled));
 548 
 549   // compute non-thread-filters events.
 550   // This must be done separately from thread-filtered events, since some
 551   // events can occur before any threads exist.
 552   JvmtiEnvIterator it;
 553   for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
 554     any_env_thread_enabled |= recompute_env_enabled(env);
 555   }
 556 
 557   // We need to create any missing jvmti_thread_state if there are globally set thread
 558   // filtered events and there weren't last time
 559   if (    (any_env_thread_enabled & THREAD_FILTERED_EVENT_BITS) != 0 &&
 560       (was_any_env_thread_enabled & THREAD_FILTERED_EVENT_BITS) == 0) {
 561     assert(JvmtiEnv::is_vm_live() || (JvmtiEnv::get_phase()==JVMTI_PHASE_START),
 562       "thread filtered events should not be enabled when VM not in start or live phase");
 563     {
 564       MutexLocker mu(Threads_lock);   //hold the Threads_lock for the iteration
 565       for (JavaThread *tp = Threads::first(); tp != NULL; tp = tp->next()) {
 566         // state_for_while_locked() makes tp->is_exiting() check
 567         JvmtiThreadState::state_for_while_locked(tp);  // create the thread state if missing
 568       }
 569     }// release Threads_lock
 570   }
 571 
 572   // compute and set thread-filtered events
 573   for (JvmtiThreadState *state = JvmtiThreadState::first(); state != NULL; state = state->next()) {
 574     any_env_thread_enabled |= recompute_thread_enabled(state);
 575   }
 576 
 577   // set universal state (across all envs and threads)
 578   jlong delta = any_env_thread_enabled ^ was_any_env_thread_enabled;
 579   if (delta != 0) {
 580     JvmtiExport::set_should_post_field_access((any_env_thread_enabled & FIELD_ACCESS_BIT) != 0);
 581     JvmtiExport::set_should_post_field_modification((any_env_thread_enabled & FIELD_MODIFICATION_BIT) != 0);
 582     JvmtiExport::set_should_post_class_load((any_env_thread_enabled & CLASS_LOAD_BIT) != 0);
 583     JvmtiExport::set_should_post_class_file_load_hook((any_env_thread_enabled & CLASS_FILE_LOAD_HOOK_BIT) != 0);
 584     JvmtiExport::set_should_post_native_method_bind((any_env_thread_enabled & NATIVE_METHOD_BIND_BIT) != 0);
 585     JvmtiExport::set_should_post_dynamic_code_generated((any_env_thread_enabled & DYNAMIC_CODE_GENERATED_BIT) != 0);
 586     JvmtiExport::set_should_post_data_dump((any_env_thread_enabled & DATA_DUMP_BIT) != 0);
 587     JvmtiExport::set_should_post_class_prepare((any_env_thread_enabled & CLASS_PREPARE_BIT) != 0);
 588     JvmtiExport::set_should_post_class_unload((any_env_thread_enabled & CLASS_UNLOAD_BIT) != 0);
 589     JvmtiExport::set_should_post_monitor_contended_enter((any_env_thread_enabled & MONITOR_CONTENDED_ENTER_BIT) != 0);
 590     JvmtiExport::set_should_post_monitor_contended_entered((any_env_thread_enabled & MONITOR_CONTENDED_ENTERED_BIT) != 0);
 591     JvmtiExport::set_should_post_monitor_wait((any_env_thread_enabled & MONITOR_WAIT_BIT) != 0);
 592     JvmtiExport::set_should_post_monitor_waited((any_env_thread_enabled & MONITOR_WAITED_BIT) != 0);
 593     JvmtiExport::set_should_post_garbage_collection_start((any_env_thread_enabled & GARBAGE_COLLECTION_START_BIT) != 0);
 594     JvmtiExport::set_should_post_garbage_collection_finish((any_env_thread_enabled & GARBAGE_COLLECTION_FINISH_BIT) != 0);
 595     JvmtiExport::set_should_post_object_free((any_env_thread_enabled & OBJECT_FREE_BIT) != 0);
 596     JvmtiExport::set_should_post_resource_exhausted((any_env_thread_enabled & RESOURCE_EXHAUSTED_BIT) != 0);
 597     JvmtiExport::set_should_post_compiled_method_load((any_env_thread_enabled & COMPILED_METHOD_LOAD_BIT) != 0);
 598     JvmtiExport::set_should_post_compiled_method_unload((any_env_thread_enabled & COMPILED_METHOD_UNLOAD_BIT) != 0);
 599     JvmtiExport::set_should_post_vm_object_alloc((any_env_thread_enabled & VM_OBJECT_ALLOC_BIT) != 0);
 600 
 601     // need this if we want thread events or we need them to init data
 602     JvmtiExport::set_should_post_thread_life((any_env_thread_enabled & NEED_THREAD_LIFE_EVENTS) != 0);
 603 
 604     // If single stepping is turned on or off, execute the VM op to change it.
 605     if (delta & SINGLE_STEP_BIT) {
 606       switch (JvmtiEnv::get_phase()) {
 607       case JVMTI_PHASE_DEAD:
 608         // If the VM is dying we can't execute VM ops
 609         break;
 610       case JVMTI_PHASE_LIVE: {
 611         VM_ChangeSingleStep op((any_env_thread_enabled & SINGLE_STEP_BIT) != 0);
 612         VMThread::execute(&op);
 613         break;
 614       }
 615       default:
 616         assert(false, "should never come here before live phase");
 617         break;
 618       }
 619     }
 620 
 621     // set global truly enabled, that is, any thread in any environment
 622     JvmtiEventController::_universal_global_event_enabled.set_bits(any_env_thread_enabled);
 623 
 624     // set global should_post_on_exceptions
 625     JvmtiExport::set_should_post_on_exceptions((any_env_thread_enabled & SHOULD_POST_ON_EXCEPTIONS_BITS) != 0);
 626 
 627   }
 628 
 629   EC_TRACE(("JVMTI [-] # recompute enabled - after %llx", any_env_thread_enabled));
 630 }
 631 
 632 
 633 void
 634 JvmtiEventControllerPrivate::thread_started(JavaThread *thread) {
 635   assert(thread->is_Java_thread(), "Must be JavaThread");
 636   assert(thread == Thread::current(), "must be current thread");
 637   assert(JvmtiEnvBase::environments_might_exist(), "to enter event controller, JVM TI environments must exist");
 638 
 639   EC_TRACE(("JVMTI [%s] # thread started", JvmtiTrace::safe_get_thread_name(thread)));
 640 
 641   // if we have any thread filtered events globally enabled, create/update the thread state
 642   if ((JvmtiEventController::_universal_global_event_enabled.get_bits() & THREAD_FILTERED_EVENT_BITS) != 0) {
 643     MutexLocker mu(JvmtiThreadState_lock);
 644     // create the thread state if missing
 645     JvmtiThreadState *state = JvmtiThreadState::state_for_while_locked(thread);
 646     if (state != NULL) {    // skip threads with no JVMTI thread state
 647       recompute_thread_enabled(state);
 648     }
 649   }
 650 }
 651 
 652 
 653 void
 654 JvmtiEventControllerPrivate::thread_ended(JavaThread *thread) {
 655   // Removes the JvmtiThreadState associated with the specified thread.
 656   // May be called after all environments have been disposed.
 657 
 658   EC_TRACE(("JVMTI [%s] # thread ended", JvmtiTrace::safe_get_thread_name(thread)));
 659 
 660   JvmtiThreadState *state = thread->jvmti_thread_state();
 661   if (state != NULL) {
 662     MutexLocker mu(JvmtiThreadState_lock);
 663     delete state;
 664   }
 665 }
 666 
 667 void JvmtiEventControllerPrivate::set_event_callbacks(JvmtiEnvBase *env,
 668                                                       const jvmtiEventCallbacks* callbacks,
 669                                                       jint size_of_callbacks) {
 670   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
 671   EC_TRACE(("JVMTI [*] # set event callbacks"));
 672 
 673   env->set_event_callbacks(callbacks, size_of_callbacks);
 674   jlong enabled_bits = 0;
 675   for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
 676     jvmtiEvent evt_t = (jvmtiEvent)ei;
 677     if (env->has_callback(evt_t)) {
 678       enabled_bits |= JvmtiEventEnabled::bit_for(evt_t);
 679     }
 680   }
 681   env->env_event_enable()->_event_callback_enabled.set_bits(enabled_bits);
 682   recompute_enabled();
 683 }
 684 
 685 void
 686 JvmtiEventControllerPrivate::set_extension_event_callback(JvmtiEnvBase *env,
 687                                                           jint extension_event_index,
 688                                                           jvmtiExtensionEvent callback)
 689 {
 690   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
 691   EC_TRACE(("JVMTI [*] # set extension event callback"));
 692 
 693   // extension events are allocated below JVMTI_MIN_EVENT_TYPE_VAL
 694   assert(extension_event_index >= (jint)EXT_MIN_EVENT_TYPE_VAL &&
 695          extension_event_index <= (jint)EXT_MAX_EVENT_TYPE_VAL, "sanity check");
 696 
 697 
 698   // As the bits for both standard (jvmtiEvent) and extension
 699   // (jvmtiExtEvents) are stored in the same word we cast here to
 700   // jvmtiEvent to set/clear the bit for this extension event.
 701   jvmtiEvent event_type = (jvmtiEvent)extension_event_index;
 702 
 703   // Prevent a possible race condition where events are re-enabled by a call to
 704   // set event callbacks, where the DisposeEnvironment occurs after the boiler-plate
 705   // environment check and before the lock is acquired.
 706   // We can safely do the is_valid check now, as JvmtiThreadState_lock is held.
 707   bool enabling = (callback != NULL) && (env->is_valid());
 708   env->env_event_enable()->set_user_enabled(event_type, enabling);
 709 
 710   // update the callback
 711   jvmtiExtEventCallbacks* ext_callbacks = env->ext_callbacks();
 712   switch (extension_event_index) {
 713     case EXT_EVENT_CLASS_UNLOAD :
 714       ext_callbacks->ClassUnload = callback;
 715       break;
 716     default:
 717       ShouldNotReachHere();
 718   }
 719 
 720   // update the callback enable/disable bit
 721   jlong enabled_bits = env->env_event_enable()->_event_callback_enabled.get_bits();
 722   jlong bit_for = JvmtiEventEnabled::bit_for(event_type);
 723   if (enabling) {
 724     enabled_bits |= bit_for;
 725   } else {
 726     enabled_bits &= ~bit_for;
 727   }
 728   env->env_event_enable()->_event_callback_enabled.set_bits(enabled_bits);
 729 
 730   recompute_enabled();
 731 }
 732 
 733 
 734 void
 735 JvmtiEventControllerPrivate::env_initialize(JvmtiEnvBase *env) {
 736   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
 737   EC_TRACE(("JVMTI [*] # env initialize"));
 738 
 739   if (JvmtiEnvBase::is_vm_live()) {
 740     // if we didn't initialize event info already (this is a late
 741     // launched environment), do it now.
 742     event_init();
 743   }
 744 
 745   env->initialize();
 746 
 747   // add the JvmtiEnvThreadState to each JvmtiThreadState
 748   for (JvmtiThreadState *state = JvmtiThreadState::first(); state != NULL; state = state->next()) {
 749     state->add_env(env);
 750     assert((JvmtiEnv*)(state->env_thread_state(env)->get_env()) == env, "sanity check");
 751   }
 752   JvmtiEventControllerPrivate::recompute_enabled();
 753 }
 754 
 755 
 756 void
 757 JvmtiEventControllerPrivate::env_dispose(JvmtiEnvBase *env) {
 758   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
 759   EC_TRACE(("JVMTI [*] # env dispose"));
 760 
 761   // Before the environment is marked disposed, disable all events on this
 762   // environment (by zapping the callbacks).  As a result, the disposed
 763   // environment will not call event handlers.
 764   set_event_callbacks(env, NULL, 0);
 765   for (jint extension_event_index = EXT_MIN_EVENT_TYPE_VAL;
 766        extension_event_index <= EXT_MAX_EVENT_TYPE_VAL;
 767        ++extension_event_index) {
 768     set_extension_event_callback(env, extension_event_index, NULL);
 769   }
 770 
 771   // Let the environment finish disposing itself.
 772   env->env_dispose();
 773 }
 774 
 775 
 776 void
 777 JvmtiEventControllerPrivate::set_user_enabled(JvmtiEnvBase *env, JavaThread *thread,
 778                                           jvmtiEvent event_type, bool enabled) {
 779   assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
 780 
 781   EC_TRACE(("JVMTI [%s] # user %s event %s",
 782             thread==NULL? "ALL": JvmtiTrace::safe_get_thread_name(thread),
 783             enabled? "enabled" : "disabled", JvmtiTrace::event_name(event_type)));
 784 
 785   if (thread == NULL) {
 786     env->env_event_enable()->set_user_enabled(event_type, enabled);
 787   } else {
 788     // create the thread state (if it didn't exist before)
 789     JvmtiThreadState *state = JvmtiThreadState::state_for_while_locked(thread);
 790     if (state != NULL) {
 791       state->env_thread_state(env)->event_enable()->set_user_enabled(event_type, enabled);
 792     }
 793   }
 794   recompute_enabled();
 795 }
 796 
 797 
 798 void
 799 JvmtiEventControllerPrivate::set_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
 800   EC_TRACE(("JVMTI [%s] # set frame pop - frame=%d",
 801             JvmtiTrace::safe_get_thread_name(ets->get_thread()),
 802             fpop.frame_number() ));
 803 
 804   ets->get_frame_pops()->set(fpop);
 805   recompute_thread_enabled(ets->get_thread()->jvmti_thread_state());
 806 }
 807 
 808 
 809 void
 810 JvmtiEventControllerPrivate::clear_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
 811   EC_TRACE(("JVMTI [%s] # clear frame pop - frame=%d",
 812             JvmtiTrace::safe_get_thread_name(ets->get_thread()),
 813             fpop.frame_number() ));
 814 
 815   ets->get_frame_pops()->clear(fpop);
 816   recompute_thread_enabled(ets->get_thread()->jvmti_thread_state());
 817 }
 818 
 819 
 820 void
 821 JvmtiEventControllerPrivate::clear_to_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
 822   int cleared_cnt = ets->get_frame_pops()->clear_to(fpop);
 823 
 824   EC_TRACE(("JVMTI [%s] # clear to frame pop - frame=%d, count=%d",
 825             JvmtiTrace::safe_get_thread_name(ets->get_thread()),
 826             fpop.frame_number(),
 827             cleared_cnt ));
 828 
 829   if (cleared_cnt > 0) {
 830     recompute_thread_enabled(ets->get_thread()->jvmti_thread_state());
 831   }
 832 }
 833 
 834 void
 835 JvmtiEventControllerPrivate::change_field_watch(jvmtiEvent event_type, bool added) {
 836   int *count_addr;
 837 
 838   switch (event_type) {
 839   case JVMTI_EVENT_FIELD_MODIFICATION:
 840     count_addr = (int *)JvmtiExport::get_field_modification_count_addr();
 841     break;
 842   case JVMTI_EVENT_FIELD_ACCESS:
 843     count_addr = (int *)JvmtiExport::get_field_access_count_addr();
 844     break;
 845   default:
 846     assert(false, "incorrect event");
 847     return;
 848   }
 849 
 850   EC_TRACE(("JVMTI [-] # change field watch - %s %s count=%d",
 851             event_type==JVMTI_EVENT_FIELD_MODIFICATION? "modification" : "access",
 852             added? "add" : "remove",
 853             *count_addr));
 854 
 855   if (added) {
 856     (*count_addr)++;
 857     if (*count_addr == 1) {
 858       recompute_enabled();
 859     }
 860   } else {
 861     if (*count_addr > 0) {
 862       (*count_addr)--;
 863       if (*count_addr == 0) {
 864         recompute_enabled();
 865       }
 866     } else {
 867       assert(false, "field watch out of phase");
 868     }
 869   }
 870 }
 871 
 872 void
 873 JvmtiEventControllerPrivate::event_init() {
 874   assert(JvmtiThreadState_lock->is_locked(), "sanity check");
 875 
 876   if (_initialized) {
 877     return;
 878   }
 879 
 880   EC_TRACE(("JVMTI [-] # VM live"));
 881 
 882 #ifdef ASSERT
 883   // check that our idea and the spec's idea of threaded events match
 884   for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
 885     jlong bit = JvmtiEventEnabled::bit_for((jvmtiEvent)ei);
 886     assert(((THREAD_FILTERED_EVENT_BITS & bit) != 0) == JvmtiUtil::event_threaded(ei),
 887            "thread filtered event list does not match");
 888   }
 889 #endif
 890 
 891   _initialized = true;
 892 }
 893 
 894 void
 895 JvmtiEventControllerPrivate::vm_start() {
 896   // some events are now able to be enabled (phase has changed)
 897   JvmtiEventControllerPrivate::recompute_enabled();
 898 }
 899 
 900 
 901 void
 902 JvmtiEventControllerPrivate::vm_init() {
 903   event_init();
 904 
 905   // all the events are now able to be enabled (phase has changed)
 906   JvmtiEventControllerPrivate::recompute_enabled();
 907 }
 908 
 909 
 910 void
 911 JvmtiEventControllerPrivate::vm_death() {
 912   // events are disabled (phase has changed)
 913   JvmtiEventControllerPrivate::recompute_enabled();
 914 }
 915 
 916 
 917 ///////////////////////////////////////////////////////////////
 918 //
 919 // JvmtiEventController
 920 //
 921 
 922 JvmtiEventEnabled JvmtiEventController::_universal_global_event_enabled;
 923 
 924 bool
 925 JvmtiEventController::is_global_event(jvmtiEvent event_type) {
 926   assert(is_valid_event_type(event_type), "invalid event type");
 927   jlong bit_for = ((jlong)1) << (event_type - TOTAL_MIN_EVENT_TYPE_VAL);
 928   return((bit_for & GLOBAL_EVENT_BITS)!=0);
 929 }
 930 
 931 void
 932 JvmtiEventController::set_user_enabled(JvmtiEnvBase *env, JavaThread *thread, jvmtiEvent event_type, bool enabled) {
 933   if (Threads::number_of_threads() == 0) {
 934     // during early VM start-up locks don't exist, but we are safely single threaded,
 935     // call the functionality without holding the JvmtiThreadState_lock.
 936     JvmtiEventControllerPrivate::set_user_enabled(env, thread, event_type, enabled);
 937   } else {
 938     MutexLocker mu(JvmtiThreadState_lock);
 939     JvmtiEventControllerPrivate::set_user_enabled(env, thread, event_type, enabled);
 940   }
 941 }
 942 
 943 
 944 void
 945 JvmtiEventController::set_event_callbacks(JvmtiEnvBase *env,
 946                                           const jvmtiEventCallbacks* callbacks,
 947                                           jint size_of_callbacks) {
 948   if (Threads::number_of_threads() == 0) {
 949     // during early VM start-up locks don't exist, but we are safely single threaded,
 950     // call the functionality without holding the JvmtiThreadState_lock.
 951     JvmtiEventControllerPrivate::set_event_callbacks(env, callbacks, size_of_callbacks);
 952   } else {
 953     MutexLocker mu(JvmtiThreadState_lock);
 954     JvmtiEventControllerPrivate::set_event_callbacks(env, callbacks, size_of_callbacks);
 955   }
 956 }
 957 
 958 void
 959 JvmtiEventController::set_extension_event_callback(JvmtiEnvBase *env,
 960                                                    jint extension_event_index,
 961                                                    jvmtiExtensionEvent callback) {
 962   if (Threads::number_of_threads() == 0) {
 963     JvmtiEventControllerPrivate::set_extension_event_callback(env, extension_event_index, callback);
 964   } else {
 965     MutexLocker mu(JvmtiThreadState_lock);
 966     JvmtiEventControllerPrivate::set_extension_event_callback(env, extension_event_index, callback);
 967   }
 968 }
 969 
 970 
 971 
 972 
 973 void
 974 JvmtiEventController::set_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
 975   MutexLocker mu(JvmtiThreadState_lock);
 976   JvmtiEventControllerPrivate::set_frame_pop(ets, fpop);
 977 }
 978 
 979 
 980 void
 981 JvmtiEventController::clear_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
 982   MutexLocker mu(JvmtiThreadState_lock);
 983   JvmtiEventControllerPrivate::clear_frame_pop(ets, fpop);
 984 }
 985 
 986 
 987 void
 988 JvmtiEventController::clear_to_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
 989   MutexLocker mu(JvmtiThreadState_lock);
 990   JvmtiEventControllerPrivate::clear_to_frame_pop(ets, fpop);
 991 }
 992 
 993 void
 994 JvmtiEventController::change_field_watch(jvmtiEvent event_type, bool added) {
 995   MutexLocker mu(JvmtiThreadState_lock);
 996   JvmtiEventControllerPrivate::change_field_watch(event_type, added);
 997 }
 998 
 999 void
1000 JvmtiEventController::thread_started(JavaThread *thread) {
1001   // operates only on the current thread
1002   // JvmtiThreadState_lock grabbed only if needed.
1003   JvmtiEventControllerPrivate::thread_started(thread);
1004 }
1005 
1006 void
1007 JvmtiEventController::thread_ended(JavaThread *thread) {
1008   // operates only on the current thread
1009   // JvmtiThreadState_lock grabbed only if needed.
1010   JvmtiEventControllerPrivate::thread_ended(thread);
1011 }
1012 
1013 void
1014 JvmtiEventController::env_initialize(JvmtiEnvBase *env) {
1015   if (Threads::number_of_threads() == 0) {
1016     // during early VM start-up locks don't exist, but we are safely single threaded,
1017     // call the functionality without holding the JvmtiThreadState_lock.
1018     JvmtiEventControllerPrivate::env_initialize(env);
1019   } else {
1020     MutexLocker mu(JvmtiThreadState_lock);
1021     JvmtiEventControllerPrivate::env_initialize(env);
1022   }
1023 }
1024 
1025 void
1026 JvmtiEventController::env_dispose(JvmtiEnvBase *env) {
1027   if (Threads::number_of_threads() == 0) {
1028     // during early VM start-up locks don't exist, but we are safely single threaded,
1029     // call the functionality without holding the JvmtiThreadState_lock.
1030     JvmtiEventControllerPrivate::env_dispose(env);
1031   } else {
1032     MutexLocker mu(JvmtiThreadState_lock);
1033     JvmtiEventControllerPrivate::env_dispose(env);
1034   }
1035 }
1036 
1037 
1038 void
1039 JvmtiEventController::vm_start() {
1040   if (JvmtiEnvBase::environments_might_exist()) {
1041     MutexLocker mu(JvmtiThreadState_lock);
1042     JvmtiEventControllerPrivate::vm_start();
1043   }
1044 }
1045 
1046 void
1047 JvmtiEventController::vm_init() {
1048   if (JvmtiEnvBase::environments_might_exist()) {
1049     MutexLocker mu(JvmtiThreadState_lock);
1050     JvmtiEventControllerPrivate::vm_init();
1051   }
1052 }
1053 
1054 void
1055 JvmtiEventController::vm_death() {
1056   if (JvmtiEnvBase::environments_might_exist()) {
1057     MutexLocker mu(JvmtiThreadState_lock);
1058     JvmtiEventControllerPrivate::vm_death();
1059   }
1060 }