1 /*
2 * Copyright (c) 2003, 2020, 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 "interpreter/interpreter.hpp"
27 #include "jvmtifiles/jvmtiEnv.hpp"
28 #include "logging/log.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "prims/jvmtiEventController.hpp"
31 #include "prims/jvmtiEventController.inline.hpp"
32 #include "prims/jvmtiExport.hpp"
33 #include "prims/jvmtiImpl.hpp"
34 #include "prims/jvmtiThreadState.inline.hpp"
35 #include "runtime/deoptimization.hpp"
36 #include "runtime/frame.inline.hpp"
37 #include "runtime/thread.inline.hpp"
38 #include "runtime/threadSMR.hpp"
39 #include "runtime/vframe.hpp"
40 #include "runtime/vframe_hp.hpp"
41 #include "runtime/vmThread.hpp"
42 #include "runtime/vmOperations.hpp"
43
44 #ifdef JVMTI_TRACE
45 #define EC_TRACE(out) do { \
46 if (JvmtiTrace::trace_event_controller()) { \
47 SafeResourceMark rm; \
48 log_trace(jvmti) out; \
49 } \
50 } while (0)
51 #else
52 #define EC_TRACE(out)
53 #endif /*JVMTI_TRACE */
54
55 // bits for standard events
56
57 static const jlong SINGLE_STEP_BIT = (((jlong)1) << (JVMTI_EVENT_SINGLE_STEP - TOTAL_MIN_EVENT_TYPE_VAL));
58 static const jlong FRAME_POP_BIT = (((jlong)1) << (JVMTI_EVENT_FRAME_POP - TOTAL_MIN_EVENT_TYPE_VAL));
59 static const jlong BREAKPOINT_BIT = (((jlong)1) << (JVMTI_EVENT_BREAKPOINT - TOTAL_MIN_EVENT_TYPE_VAL));
60 static const jlong FIELD_ACCESS_BIT = (((jlong)1) << (JVMTI_EVENT_FIELD_ACCESS - TOTAL_MIN_EVENT_TYPE_VAL));
61 static const jlong FIELD_MODIFICATION_BIT = (((jlong)1) << (JVMTI_EVENT_FIELD_MODIFICATION - TOTAL_MIN_EVENT_TYPE_VAL));
62 static const jlong METHOD_ENTRY_BIT = (((jlong)1) << (JVMTI_EVENT_METHOD_ENTRY - TOTAL_MIN_EVENT_TYPE_VAL));
63 static const jlong METHOD_EXIT_BIT = (((jlong)1) << (JVMTI_EVENT_METHOD_EXIT - TOTAL_MIN_EVENT_TYPE_VAL));
64 static const jlong CLASS_FILE_LOAD_HOOK_BIT = (((jlong)1) << (JVMTI_EVENT_CLASS_FILE_LOAD_HOOK - TOTAL_MIN_EVENT_TYPE_VAL));
65 static const jlong NATIVE_METHOD_BIND_BIT = (((jlong)1) << (JVMTI_EVENT_NATIVE_METHOD_BIND - TOTAL_MIN_EVENT_TYPE_VAL));
66 static const jlong VM_START_BIT = (((jlong)1) << (JVMTI_EVENT_VM_START - TOTAL_MIN_EVENT_TYPE_VAL));
67 static const jlong VM_INIT_BIT = (((jlong)1) << (JVMTI_EVENT_VM_INIT - TOTAL_MIN_EVENT_TYPE_VAL));
68 static const jlong VM_DEATH_BIT = (((jlong)1) << (JVMTI_EVENT_VM_DEATH - TOTAL_MIN_EVENT_TYPE_VAL));
69 static const jlong CLASS_LOAD_BIT = (((jlong)1) << (JVMTI_EVENT_CLASS_LOAD - TOTAL_MIN_EVENT_TYPE_VAL));
70 static const jlong CLASS_PREPARE_BIT = (((jlong)1) << (JVMTI_EVENT_CLASS_PREPARE - TOTAL_MIN_EVENT_TYPE_VAL));
71 static const jlong THREAD_START_BIT = (((jlong)1) << (JVMTI_EVENT_THREAD_START - TOTAL_MIN_EVENT_TYPE_VAL));
72 static const jlong THREAD_END_BIT = (((jlong)1) << (JVMTI_EVENT_THREAD_END - TOTAL_MIN_EVENT_TYPE_VAL));
73 static const jlong EXCEPTION_THROW_BIT = (((jlong)1) << (JVMTI_EVENT_EXCEPTION - TOTAL_MIN_EVENT_TYPE_VAL));
74 static const jlong EXCEPTION_CATCH_BIT = (((jlong)1) << (JVMTI_EVENT_EXCEPTION_CATCH - TOTAL_MIN_EVENT_TYPE_VAL));
75 static const jlong MONITOR_CONTENDED_ENTER_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_CONTENDED_ENTER - TOTAL_MIN_EVENT_TYPE_VAL));
76 static const jlong MONITOR_CONTENDED_ENTERED_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_CONTENDED_ENTERED - TOTAL_MIN_EVENT_TYPE_VAL));
77 static const jlong MONITOR_WAIT_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_WAIT - TOTAL_MIN_EVENT_TYPE_VAL));
78 static const jlong MONITOR_WAITED_BIT = (((jlong)1) << (JVMTI_EVENT_MONITOR_WAITED - TOTAL_MIN_EVENT_TYPE_VAL));
79 static const jlong DYNAMIC_CODE_GENERATED_BIT = (((jlong)1) << (JVMTI_EVENT_DYNAMIC_CODE_GENERATED - TOTAL_MIN_EVENT_TYPE_VAL));
80 static const jlong DATA_DUMP_BIT = (((jlong)1) << (JVMTI_EVENT_DATA_DUMP_REQUEST - TOTAL_MIN_EVENT_TYPE_VAL));
81 static const jlong COMPILED_METHOD_LOAD_BIT = (((jlong)1) << (JVMTI_EVENT_COMPILED_METHOD_LOAD - TOTAL_MIN_EVENT_TYPE_VAL));
82 static const jlong COMPILED_METHOD_UNLOAD_BIT = (((jlong)1) << (JVMTI_EVENT_COMPILED_METHOD_UNLOAD - TOTAL_MIN_EVENT_TYPE_VAL));
83 static const jlong GARBAGE_COLLECTION_START_BIT = (((jlong)1) << (JVMTI_EVENT_GARBAGE_COLLECTION_START - TOTAL_MIN_EVENT_TYPE_VAL));
84 static const jlong GARBAGE_COLLECTION_FINISH_BIT = (((jlong)1) << (JVMTI_EVENT_GARBAGE_COLLECTION_FINISH - TOTAL_MIN_EVENT_TYPE_VAL));
85 static const jlong OBJECT_FREE_BIT = (((jlong)1) << (JVMTI_EVENT_OBJECT_FREE - TOTAL_MIN_EVENT_TYPE_VAL));
86 static const jlong RESOURCE_EXHAUSTED_BIT = (((jlong)1) << (JVMTI_EVENT_RESOURCE_EXHAUSTED - TOTAL_MIN_EVENT_TYPE_VAL));
87 static const jlong VM_OBJECT_ALLOC_BIT = (((jlong)1) << (JVMTI_EVENT_VM_OBJECT_ALLOC - TOTAL_MIN_EVENT_TYPE_VAL));
88 static const jlong SAMPLED_OBJECT_ALLOC_BIT = (((jlong)1) << (JVMTI_EVENT_SAMPLED_OBJECT_ALLOC - TOTAL_MIN_EVENT_TYPE_VAL));
89
90 // bits for extension events
91 static const jlong CLASS_UNLOAD_BIT = (((jlong)1) << (EXT_EVENT_CLASS_UNLOAD - TOTAL_MIN_EVENT_TYPE_VAL));
92
93
94 static const jlong MONITOR_BITS = MONITOR_CONTENDED_ENTER_BIT | MONITOR_CONTENDED_ENTERED_BIT |
95 MONITOR_WAIT_BIT | MONITOR_WAITED_BIT;
96 static const jlong EXCEPTION_BITS = EXCEPTION_THROW_BIT | EXCEPTION_CATCH_BIT;
97 static const jlong INTERP_EVENT_BITS = SINGLE_STEP_BIT | METHOD_ENTRY_BIT | METHOD_EXIT_BIT |
98 FRAME_POP_BIT | FIELD_ACCESS_BIT | FIELD_MODIFICATION_BIT;
99 static const jlong THREAD_FILTERED_EVENT_BITS = INTERP_EVENT_BITS | EXCEPTION_BITS | MONITOR_BITS |
100 BREAKPOINT_BIT | CLASS_LOAD_BIT | CLASS_PREPARE_BIT | THREAD_END_BIT |
101 SAMPLED_OBJECT_ALLOC_BIT;
102 static const jlong NEED_THREAD_LIFE_EVENTS = THREAD_FILTERED_EVENT_BITS | THREAD_START_BIT;
103 static const jlong EARLY_EVENT_BITS = CLASS_FILE_LOAD_HOOK_BIT | CLASS_LOAD_BIT | CLASS_PREPARE_BIT |
104 VM_START_BIT | VM_INIT_BIT | VM_DEATH_BIT | NATIVE_METHOD_BIND_BIT |
105 THREAD_START_BIT | THREAD_END_BIT |
106 COMPILED_METHOD_LOAD_BIT | COMPILED_METHOD_UNLOAD_BIT |
107 DYNAMIC_CODE_GENERATED_BIT;
108 static const jlong GLOBAL_EVENT_BITS = ~THREAD_FILTERED_EVENT_BITS;
109 static const jlong SHOULD_POST_ON_EXCEPTIONS_BITS = EXCEPTION_BITS | METHOD_EXIT_BIT | FRAME_POP_BIT;
110
111 ///////////////////////////////////////////////////////////////
112 //
113 // JvmtiEventEnabled
114 //
115
116 JvmtiEventEnabled::JvmtiEventEnabled() {
117 clear();
118 }
119
120
121 void JvmtiEventEnabled::clear() {
122 _enabled_bits = 0;
123 #ifndef PRODUCT
124 _init_guard = JEE_INIT_GUARD;
125 #endif
126 }
127
128 void JvmtiEventEnabled::set_enabled(jvmtiEvent event_type, bool enabled) {
129 jlong bits = get_bits();
130 jlong mask = bit_for(event_type);
131 if (enabled) {
132 bits |= mask;
133 } else {
134 bits &= ~mask;
135 }
136 set_bits(bits);
137 }
138
139
140 ///////////////////////////////////////////////////////////////
141 //
142 // JvmtiEnvThreadEventEnable
143 //
144
145 JvmtiEnvThreadEventEnable::JvmtiEnvThreadEventEnable() {
146 _event_user_enabled.clear();
147 _event_enabled.clear();
148 }
149
150
151 JvmtiEnvThreadEventEnable::~JvmtiEnvThreadEventEnable() {
152 _event_user_enabled.clear();
153 _event_enabled.clear();
154 }
155
156
157 ///////////////////////////////////////////////////////////////
158 //
159 // JvmtiThreadEventEnable
160 //
161
162 JvmtiThreadEventEnable::JvmtiThreadEventEnable() {
163 _event_enabled.clear();
164 }
165
166
167 JvmtiThreadEventEnable::~JvmtiThreadEventEnable() {
168 _event_enabled.clear();
169 }
170
171
172 ///////////////////////////////////////////////////////////////
173 //
174 // JvmtiEnvEventEnable
175 //
176
177 JvmtiEnvEventEnable::JvmtiEnvEventEnable() {
178 _event_user_enabled.clear();
179 _event_callback_enabled.clear();
180 _event_enabled.clear();
181 }
182
183
184 JvmtiEnvEventEnable::~JvmtiEnvEventEnable() {
185 _event_user_enabled.clear();
186 _event_callback_enabled.clear();
187 _event_enabled.clear();
188 }
189
190
191 ///////////////////////////////////////////////////////////////
192 //
193 // EnterInterpOnlyModeClosure
194 //
195
196 class EnterInterpOnlyModeClosure : public HandshakeClosure {
197
198 public:
199 EnterInterpOnlyModeClosure() : HandshakeClosure("EnterInterpOnlyMode") { }
200 void do_thread(Thread* th) {
201 JavaThread* jt = (JavaThread*) th;
202 JvmtiThreadState* state = jt->jvmti_thread_state();
203
204 // Set up the current stack depth for later tracking
205 state->invalidate_cur_stack_depth();
206
207 state->enter_interp_only_mode();
208
209 if (jt->has_last_Java_frame()) {
210 // If running in fullspeed mode, single stepping is implemented
211 // as follows: first, the interpreter does not dispatch to
212 // compiled code for threads that have single stepping enabled;
213 // second, we deoptimize all compiled java frames on the thread's stack when
214 // interpreted-only mode is enabled the first time for a given
215 // thread (nothing to do if no Java frames yet).
216 ResourceMark resMark;
217 for (StackFrameStream fst(jt, false); !fst.is_done(); fst.next()) {
218 if (fst.current()->can_be_deoptimized()) {
219 Deoptimization::deoptimize(jt, *fst.current());
220 }
221 }
222 }
223 }
224 };
225
226
227 ///////////////////////////////////////////////////////////////
228 //
229 // VM_ChangeSingleStep
230 //
231
232 class VM_ChangeSingleStep : public VM_Operation {
233 private:
234 bool _on;
235
236 public:
237 VM_ChangeSingleStep(bool on);
238 VMOp_Type type() const { return VMOp_ChangeSingleStep; }
239 bool allow_nested_vm_operations() const { return true; }
240 void doit(); // method definition is after definition of JvmtiEventControllerPrivate because of scoping
241 };
242
243
244 VM_ChangeSingleStep::VM_ChangeSingleStep(bool on)
245 : _on(on)
246 {
247 }
248
249
250
251
252 ///////////////////////////////////////////////////////////////
253 //
254 // JvmtiEventControllerPrivate
255 //
256 // Private internal implementation methods for JvmtiEventController.
257 //
258 // These methods are thread safe either because they are called
259 // in early VM initialization which is single threaded, or they
260 // hold the JvmtiThreadState_lock.
261 //
262
263 class JvmtiEventControllerPrivate : public AllStatic {
264 static bool _initialized;
265 public:
266 static void set_should_post_single_step(bool on);
267 static void enter_interp_only_mode(JvmtiThreadState *state);
268 static void leave_interp_only_mode(JvmtiThreadState *state);
269 static void recompute_enabled();
270 static jlong recompute_env_enabled(JvmtiEnvBase* env);
271 static jlong recompute_env_thread_enabled(JvmtiEnvThreadState* ets, JvmtiThreadState* state);
272 static jlong recompute_thread_enabled(JvmtiThreadState *state);
273 static void event_init();
274
275 static void set_user_enabled(JvmtiEnvBase *env, JavaThread *thread,
276 jvmtiEvent event_type, bool enabled);
277 static void set_event_callbacks(JvmtiEnvBase *env,
278 const jvmtiEventCallbacks* callbacks,
279 jint size_of_callbacks);
280
281 static void set_extension_event_callback(JvmtiEnvBase *env,
282 jint extension_event_index,
283 jvmtiExtensionEvent callback);
284
285 static void set_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
286 static void clear_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
287 static void clear_to_frame_pop(JvmtiEnvThreadState *env_thread, JvmtiFramePop fpop);
288 static void change_field_watch(jvmtiEvent event_type, bool added);
289
290 static void thread_started(JavaThread *thread);
291 static void thread_ended(JavaThread *thread);
292
293 static void env_initialize(JvmtiEnvBase *env);
294 static void env_dispose(JvmtiEnvBase *env);
295
296 static void vm_start();
297 static void vm_init();
298 static void vm_death();
299
300 static void trace_changed(JvmtiThreadState *state, jlong now_enabled, jlong changed);
301 static void trace_changed(jlong now_enabled, jlong changed);
302 };
303
304 bool JvmtiEventControllerPrivate::_initialized = false;
305
306 void JvmtiEventControllerPrivate::set_should_post_single_step(bool on) {
307 // we have permission to do this, VM op doesn't
308 JvmtiExport::set_should_post_single_step(on);
309 }
310
311
312 // When _on == true, we use the safepoint interpreter dispatch table
313 // to allow us to find the single step points. Otherwise, we switch
314 // back to the regular interpreter dispatch table.
315 // Note: We call Interpreter::notice_safepoints() and ignore_safepoints()
316 // in a VM_Operation to safely make the dispatch table switch. We
317 // no longer rely on the safepoint mechanism to do any of this work
318 // for us.
319 void VM_ChangeSingleStep::doit() {
320 log_debug(interpreter, safepoint)("changing single step to '%s'", _on ? "on" : "off");
321 JvmtiEventControllerPrivate::set_should_post_single_step(_on);
322 if (_on) {
323 Interpreter::notice_safepoints();
324 } else {
325 Interpreter::ignore_safepoints();
326 }
327 }
328
329
330 void JvmtiEventControllerPrivate::enter_interp_only_mode(JvmtiThreadState *state) {
331 EC_TRACE(("[%s] # Entering interpreter only mode",
332 JvmtiTrace::safe_get_thread_name(state->get_thread())));
333 EnterInterpOnlyModeClosure hs;
334 if (SafepointSynchronize::is_at_safepoint()) {
335 hs.do_thread(state->get_thread());
336 } else {
337 Handshake::execute_direct(&hs, state->get_thread());
338 }
339 }
340
341
342 void
343 JvmtiEventControllerPrivate::leave_interp_only_mode(JvmtiThreadState *state) {
344 EC_TRACE(("[%s] # Leaving interpreter only mode",
345 JvmtiTrace::safe_get_thread_name(state->get_thread())));
346 state->leave_interp_only_mode();
347 }
348
349
350 void
351 JvmtiEventControllerPrivate::trace_changed(JvmtiThreadState *state, jlong now_enabled, jlong changed) {
352 #ifdef JVMTI_TRACE
353 if (JvmtiTrace::trace_event_controller()) {
354 SafeResourceMark rm;
355 // traces standard events only
356 for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
357 jlong bit = JvmtiEventEnabled::bit_for((jvmtiEvent)ei);
358 if (changed & bit) {
359 // it changed, print it
360 log_trace(jvmti)("[%s] # %s event %s",
361 JvmtiTrace::safe_get_thread_name(state->get_thread()),
362 (now_enabled & bit)? "Enabling" : "Disabling", JvmtiTrace::event_name((jvmtiEvent)ei));
363 }
364 }
365 }
366 #endif /*JVMTI_TRACE */
367 }
368
369
370 void
371 JvmtiEventControllerPrivate::trace_changed(jlong now_enabled, jlong changed) {
372 #ifdef JVMTI_TRACE
373 if (JvmtiTrace::trace_event_controller()) {
374 SafeResourceMark rm;
375 // traces standard events only
376 for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
377 jlong bit = JvmtiEventEnabled::bit_for((jvmtiEvent)ei);
378 if (changed & bit) {
379 // it changed, print it
380 log_trace(jvmti)("[-] # %s event %s",
381 (now_enabled & bit)? "Enabling" : "Disabling", JvmtiTrace::event_name((jvmtiEvent)ei));
382 }
383 }
384 }
385 #endif /*JVMTI_TRACE */
386 }
387
388
389 // For the specified env: compute the currently truly enabled events
390 // set external state accordingly.
391 // Return value and set value must include all events.
392 // But outside this class, only non-thread-filtered events can be queried..
393 jlong
394 JvmtiEventControllerPrivate::recompute_env_enabled(JvmtiEnvBase* env) {
395 jlong was_enabled = env->env_event_enable()->_event_enabled.get_bits();
396 jlong now_enabled =
397 env->env_event_enable()->_event_callback_enabled.get_bits() &
398 env->env_event_enable()->_event_user_enabled.get_bits();
399
400 switch (env->phase()) {
401 case JVMTI_PHASE_PRIMORDIAL:
402 case JVMTI_PHASE_ONLOAD:
403 // only these events allowed in primordial or onload phase
404 now_enabled &= (EARLY_EVENT_BITS & ~THREAD_FILTERED_EVENT_BITS);
405 break;
406 case JVMTI_PHASE_START:
407 // only these events allowed in start phase
408 now_enabled &= EARLY_EVENT_BITS;
409 break;
410 case JVMTI_PHASE_LIVE:
411 // all events allowed during live phase
412 break;
413 case JVMTI_PHASE_DEAD:
414 // no events allowed when dead
415 now_enabled = 0;
416 break;
417 default:
418 assert(false, "no other phases - sanity check");
419 break;
420 }
421
422 // will we really send these events to this env
423 env->env_event_enable()->_event_enabled.set_bits(now_enabled);
424
425 trace_changed(now_enabled, (now_enabled ^ was_enabled) & ~THREAD_FILTERED_EVENT_BITS);
426
427 return now_enabled;
428 }
429
430
431 // For the specified env and thread: compute the currently truly enabled events
432 // set external state accordingly. Only thread-filtered events are included.
433 jlong
434 JvmtiEventControllerPrivate::recompute_env_thread_enabled(JvmtiEnvThreadState* ets, JvmtiThreadState* state) {
435 JvmtiEnv *env = ets->get_env();
436
437 jlong was_enabled = ets->event_enable()->_event_enabled.get_bits();
438 jlong now_enabled = THREAD_FILTERED_EVENT_BITS &
439 env->env_event_enable()->_event_callback_enabled.get_bits() &
440 (env->env_event_enable()->_event_user_enabled.get_bits() |
441 ets->event_enable()->_event_user_enabled.get_bits());
442
443 // for frame pops and field watchs, computed enabled state
444 // is only true if an event has been requested
445 if (!ets->has_frame_pops()) {
446 now_enabled &= ~FRAME_POP_BIT;
447 }
448 if (*((int *)JvmtiExport::get_field_access_count_addr()) == 0) {
449 now_enabled &= ~FIELD_ACCESS_BIT;
450 }
451 if (*((int *)JvmtiExport::get_field_modification_count_addr()) == 0) {
452 now_enabled &= ~FIELD_MODIFICATION_BIT;
453 }
454
455 switch (JvmtiEnv::get_phase()) {
456 case JVMTI_PHASE_DEAD:
457 // no events allowed when dead
458 now_enabled = 0;
459 break;
460 default:
461 break;
462 }
463
464 // if anything changed do update
465 if (now_enabled != was_enabled) {
466
467 // will we really send these events to this thread x env
468 ets->event_enable()->_event_enabled.set_bits(now_enabled);
469
470 // If the enabled status of the single step or breakpoint events changed,
471 // the location status may need to change as well.
472 jlong changed = now_enabled ^ was_enabled;
473 if (changed & SINGLE_STEP_BIT) {
474 ets->reset_current_location(JVMTI_EVENT_SINGLE_STEP, (now_enabled & SINGLE_STEP_BIT) != 0);
475 }
476 if (changed & BREAKPOINT_BIT) {
477 ets->reset_current_location(JVMTI_EVENT_BREAKPOINT, (now_enabled & BREAKPOINT_BIT) != 0);
478 }
479 trace_changed(state, now_enabled, changed);
480 }
481 return now_enabled;
482 }
483
484
485 // For the specified thread: compute the currently truly enabled events
486 // set external state accordingly. Only thread-filtered events are included.
487 jlong
488 JvmtiEventControllerPrivate::recompute_thread_enabled(JvmtiThreadState *state) {
489 if (state == NULL) {
490 // associated JavaThread is exiting
491 return (jlong)0;
492 }
493
494 julong was_any_env_enabled = state->thread_event_enable()->_event_enabled.get_bits();
495 julong any_env_enabled = 0;
496 // JVMTI_EVENT_FRAME_POP can be disabled (in the case FRAME_POP_BIT is not set),
497 // but we need to set interp_only if some JvmtiEnvThreadState has frame pop set
498 // to clear the request
499 bool has_frame_pops = false;
500
501 {
502 // This iteration will include JvmtiEnvThreadStates whose environments
503 // have been disposed. These JvmtiEnvThreadStates must not be filtered
504 // as recompute must be called on them to disable their events,
505 JvmtiEnvThreadStateIterator it(state);
506 for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {
507 any_env_enabled |= recompute_env_thread_enabled(ets, state);
508 has_frame_pops |= ets->has_frame_pops();
509 }
510 }
511
512 if (any_env_enabled != was_any_env_enabled) {
513 // mark if event is truly enabled on this thread in any environment
514 state->thread_event_enable()->_event_enabled.set_bits(any_env_enabled);
515
516 // update the JavaThread cached value for thread-specific should_post_on_exceptions value
517 bool should_post_on_exceptions = (any_env_enabled & SHOULD_POST_ON_EXCEPTIONS_BITS) != 0;
518 state->set_should_post_on_exceptions(should_post_on_exceptions);
519 }
520
521 // compute interp_only mode
522 bool should_be_interp = (any_env_enabled & INTERP_EVENT_BITS) != 0 || has_frame_pops;
523 bool is_now_interp = state->is_interp_only_mode();
524
525 if (should_be_interp != is_now_interp) {
526 if (should_be_interp) {
527 enter_interp_only_mode(state);
528 } else {
529 leave_interp_only_mode(state);
530 }
531 }
532
533 return any_env_enabled;
534 }
535
536
537 // Compute truly enabled events - meaning if the event can and could be
538 // sent. An event is truly enabled if it is user enabled on the thread
539 // or globally user enabled, but only if there is a callback or event hook
540 // for it and, for field watch and frame pop, one has been set.
541 // Compute if truly enabled, per thread, per environment, per combination
542 // (thread x environment), and overall. These merges are true if any is true.
543 // True per thread if some environment has callback set and the event is globally
544 // enabled or enabled for this thread.
545 // True per environment if the callback is set and the event is globally
546 // enabled in this environment or enabled for any thread in this environment.
547 // True per combination if the environment has the callback set and the
548 // event is globally enabled in this environment or the event is enabled
549 // for this thread and environment.
550 //
551 // All states transitions dependent on these transitions are also handled here.
552 void
553 JvmtiEventControllerPrivate::recompute_enabled() {
554 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
555
556 // event enabled for any thread in any environment
557 julong was_any_env_thread_enabled = JvmtiEventController::_universal_global_event_enabled.get_bits();
558 julong any_env_thread_enabled = 0;
559
560 EC_TRACE(("[-] # recompute enabled - before " JULONG_FORMAT_X, was_any_env_thread_enabled));
561
562 // compute non-thread-filters events.
563 // This must be done separately from thread-filtered events, since some
564 // events can occur before any threads exist.
565 JvmtiEnvIterator it;
566 for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
567 any_env_thread_enabled |= recompute_env_enabled(env);
568 }
569
570 // We need to create any missing jvmti_thread_state if there are globally set thread
571 // filtered events and there weren't last time
572 if ( (any_env_thread_enabled & THREAD_FILTERED_EVENT_BITS) != 0 &&
573 (was_any_env_thread_enabled & THREAD_FILTERED_EVENT_BITS) == 0) {
574 for (JavaThreadIteratorWithHandle jtiwh; JavaThread *tp = jtiwh.next(); ) {
575 // state_for_while_locked() makes tp->is_exiting() check
576 JvmtiThreadState::state_for_while_locked(tp); // create the thread state if missing
577 }
578 }
579
580 // compute and set thread-filtered events
581 for (JvmtiThreadState *state = JvmtiThreadState::first(); state != NULL; state = state->next()) {
582 any_env_thread_enabled |= recompute_thread_enabled(state);
583 }
584
585 // set universal state (across all envs and threads)
586 jlong delta = any_env_thread_enabled ^ was_any_env_thread_enabled;
587 if (delta != 0) {
588 JvmtiExport::set_should_post_field_access((any_env_thread_enabled & FIELD_ACCESS_BIT) != 0);
589 JvmtiExport::set_should_post_field_modification((any_env_thread_enabled & FIELD_MODIFICATION_BIT) != 0);
590 JvmtiExport::set_should_post_class_load((any_env_thread_enabled & CLASS_LOAD_BIT) != 0);
591 JvmtiExport::set_should_post_class_file_load_hook((any_env_thread_enabled & CLASS_FILE_LOAD_HOOK_BIT) != 0);
592 JvmtiExport::set_should_post_native_method_bind((any_env_thread_enabled & NATIVE_METHOD_BIND_BIT) != 0);
593 JvmtiExport::set_should_post_dynamic_code_generated((any_env_thread_enabled & DYNAMIC_CODE_GENERATED_BIT) != 0);
594 JvmtiExport::set_should_post_data_dump((any_env_thread_enabled & DATA_DUMP_BIT) != 0);
595 JvmtiExport::set_should_post_class_prepare((any_env_thread_enabled & CLASS_PREPARE_BIT) != 0);
596 JvmtiExport::set_should_post_class_unload((any_env_thread_enabled & CLASS_UNLOAD_BIT) != 0);
597 JvmtiExport::set_should_post_monitor_contended_enter((any_env_thread_enabled & MONITOR_CONTENDED_ENTER_BIT) != 0);
598 JvmtiExport::set_should_post_monitor_contended_entered((any_env_thread_enabled & MONITOR_CONTENDED_ENTERED_BIT) != 0);
599 JvmtiExport::set_should_post_monitor_wait((any_env_thread_enabled & MONITOR_WAIT_BIT) != 0);
600 JvmtiExport::set_should_post_monitor_waited((any_env_thread_enabled & MONITOR_WAITED_BIT) != 0);
601 JvmtiExport::set_should_post_garbage_collection_start((any_env_thread_enabled & GARBAGE_COLLECTION_START_BIT) != 0);
602 JvmtiExport::set_should_post_garbage_collection_finish((any_env_thread_enabled & GARBAGE_COLLECTION_FINISH_BIT) != 0);
603 JvmtiExport::set_should_post_object_free((any_env_thread_enabled & OBJECT_FREE_BIT) != 0);
604 JvmtiExport::set_should_post_resource_exhausted((any_env_thread_enabled & RESOURCE_EXHAUSTED_BIT) != 0);
605 JvmtiExport::set_should_post_compiled_method_load((any_env_thread_enabled & COMPILED_METHOD_LOAD_BIT) != 0);
606 JvmtiExport::set_should_post_compiled_method_unload((any_env_thread_enabled & COMPILED_METHOD_UNLOAD_BIT) != 0);
607 JvmtiExport::set_should_post_vm_object_alloc((any_env_thread_enabled & VM_OBJECT_ALLOC_BIT) != 0);
608 JvmtiExport::set_should_post_sampled_object_alloc((any_env_thread_enabled & SAMPLED_OBJECT_ALLOC_BIT) != 0);
609
610 // need this if we want thread events or we need them to init data
611 JvmtiExport::set_should_post_thread_life((any_env_thread_enabled & NEED_THREAD_LIFE_EVENTS) != 0);
612
613 // If single stepping is turned on or off, execute the VM op to change it.
614 if (delta & SINGLE_STEP_BIT) {
615 switch (JvmtiEnv::get_phase()) {
616 case JVMTI_PHASE_DEAD:
617 // If the VM is dying we can't execute VM ops
618 break;
619 case JVMTI_PHASE_LIVE: {
620 VM_ChangeSingleStep op((any_env_thread_enabled & SINGLE_STEP_BIT) != 0);
621 VMThread::execute(&op);
622 break;
623 }
624 default:
625 assert(false, "should never come here before live phase");
626 break;
627 }
628 }
629
630 // set global truly enabled, that is, any thread in any environment
631 JvmtiEventController::_universal_global_event_enabled.set_bits(any_env_thread_enabled);
632
633 // set global should_post_on_exceptions
634 JvmtiExport::set_should_post_on_exceptions((any_env_thread_enabled & SHOULD_POST_ON_EXCEPTIONS_BITS) != 0);
635
636 }
637
638 EC_TRACE(("[-] # recompute enabled - after " JULONG_FORMAT_X, any_env_thread_enabled));
639 }
640
641
642 void
643 JvmtiEventControllerPrivate::thread_started(JavaThread *thread) {
644 assert(thread->is_Java_thread(), "Must be JavaThread");
645 assert(thread == Thread::current(), "must be current thread");
646 assert(JvmtiEnvBase::environments_might_exist(), "to enter event controller, JVM TI environments must exist");
647
648 EC_TRACE(("[%s] # thread started", JvmtiTrace::safe_get_thread_name(thread)));
649
650 // if we have any thread filtered events globally enabled, create/update the thread state
651 if ((JvmtiEventController::_universal_global_event_enabled.get_bits() & THREAD_FILTERED_EVENT_BITS) != 0) {
652 MutexLocker mu(JvmtiThreadState_lock);
653 // create the thread state if missing
654 JvmtiThreadState *state = JvmtiThreadState::state_for_while_locked(thread);
655 if (state != NULL) { // skip threads with no JVMTI thread state
656 recompute_thread_enabled(state);
657 }
658 }
659 }
660
661
662 void
663 JvmtiEventControllerPrivate::thread_ended(JavaThread *thread) {
664 // Removes the JvmtiThreadState associated with the specified thread.
665 // May be called after all environments have been disposed.
666 assert(JvmtiThreadState_lock->is_locked(), "sanity check");
667
668 EC_TRACE(("[%s] # thread ended", JvmtiTrace::safe_get_thread_name(thread)));
669
670 JvmtiThreadState *state = thread->jvmti_thread_state();
671 assert(state != NULL, "else why are we here?");
672 delete state;
673 }
674
675 void JvmtiEventControllerPrivate::set_event_callbacks(JvmtiEnvBase *env,
676 const jvmtiEventCallbacks* callbacks,
677 jint size_of_callbacks) {
678 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
679 EC_TRACE(("[*] # set event callbacks"));
680
681 env->set_event_callbacks(callbacks, size_of_callbacks);
682 jlong enabled_bits = 0;
683 for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
684 jvmtiEvent evt_t = (jvmtiEvent)ei;
685 if (env->has_callback(evt_t)) {
686 enabled_bits |= JvmtiEventEnabled::bit_for(evt_t);
687 }
688 }
689 env->env_event_enable()->_event_callback_enabled.set_bits(enabled_bits);
690 recompute_enabled();
691 }
692
693 void
694 JvmtiEventControllerPrivate::set_extension_event_callback(JvmtiEnvBase *env,
695 jint extension_event_index,
696 jvmtiExtensionEvent callback)
697 {
698 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
699 EC_TRACE(("[*] # set extension event callback"));
700
701 // extension events are allocated below JVMTI_MIN_EVENT_TYPE_VAL
702 assert(extension_event_index >= (jint)EXT_MIN_EVENT_TYPE_VAL &&
703 extension_event_index <= (jint)EXT_MAX_EVENT_TYPE_VAL, "sanity check");
704
705
706 // As the bits for both standard (jvmtiEvent) and extension
707 // (jvmtiExtEvents) are stored in the same word we cast here to
708 // jvmtiEvent to set/clear the bit for this extension event.
709 jvmtiEvent event_type = (jvmtiEvent)extension_event_index;
710
711 // Prevent a possible race condition where events are re-enabled by a call to
712 // set event callbacks, where the DisposeEnvironment occurs after the boiler-plate
713 // environment check and before the lock is acquired.
714 // We can safely do the is_valid check now, as JvmtiThreadState_lock is held.
715 bool enabling = (callback != NULL) && (env->is_valid());
716 env->env_event_enable()->set_user_enabled(event_type, enabling);
717
718 // update the callback
719 jvmtiExtEventCallbacks* ext_callbacks = env->ext_callbacks();
720 switch (extension_event_index) {
721 case EXT_EVENT_CLASS_UNLOAD :
722 ext_callbacks->ClassUnload = callback;
723 break;
724 default:
725 ShouldNotReachHere();
726 }
727
728 // update the callback enable/disable bit
729 jlong enabled_bits = env->env_event_enable()->_event_callback_enabled.get_bits();
730 jlong bit_for = JvmtiEventEnabled::bit_for(event_type);
731 if (enabling) {
732 enabled_bits |= bit_for;
733 } else {
734 enabled_bits &= ~bit_for;
735 }
736 env->env_event_enable()->_event_callback_enabled.set_bits(enabled_bits);
737
738 recompute_enabled();
739 }
740
741
742 void
743 JvmtiEventControllerPrivate::env_initialize(JvmtiEnvBase *env) {
744 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
745 EC_TRACE(("[*] # env initialize"));
746
747 if (JvmtiEnvBase::is_vm_live()) {
748 // if we didn't initialize event info already (this is a late
749 // launched environment), do it now.
750 event_init();
751 }
752
753 env->initialize();
754
755 // add the JvmtiEnvThreadState to each JvmtiThreadState
756 for (JvmtiThreadState *state = JvmtiThreadState::first(); state != NULL; state = state->next()) {
757 state->add_env(env);
758 assert((JvmtiEnv*)(state->env_thread_state(env)->get_env()) == env, "sanity check");
759 }
760 JvmtiEventControllerPrivate::recompute_enabled();
761 }
762
763
764 void
765 JvmtiEventControllerPrivate::env_dispose(JvmtiEnvBase *env) {
766 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
767 EC_TRACE(("[*] # env dispose"));
768
769 // Before the environment is marked disposed, disable all events on this
770 // environment (by zapping the callbacks). As a result, the disposed
771 // environment will not call event handlers.
772 set_event_callbacks(env, NULL, 0);
773 for (jint extension_event_index = EXT_MIN_EVENT_TYPE_VAL;
774 extension_event_index <= EXT_MAX_EVENT_TYPE_VAL;
775 ++extension_event_index) {
776 set_extension_event_callback(env, extension_event_index, NULL);
777 }
778
779 // Let the environment finish disposing itself.
780 env->env_dispose();
781 }
782
783
784 void
785 JvmtiEventControllerPrivate::set_user_enabled(JvmtiEnvBase *env, JavaThread *thread,
786 jvmtiEvent event_type, bool enabled) {
787 assert(Threads::number_of_threads() == 0 || JvmtiThreadState_lock->is_locked(), "sanity check");
788
789 EC_TRACE(("[%s] # user %s event %s",
790 thread==NULL? "ALL": JvmtiTrace::safe_get_thread_name(thread),
791 enabled? "enabled" : "disabled", JvmtiTrace::event_name(event_type)));
792
793 if (thread == NULL) {
794 env->env_event_enable()->set_user_enabled(event_type, enabled);
795 } else {
796 // create the thread state (if it didn't exist before)
797 JvmtiThreadState *state = JvmtiThreadState::state_for_while_locked(thread);
798 if (state != NULL) {
799 state->env_thread_state(env)->event_enable()->set_user_enabled(event_type, enabled);
800 }
801 }
802 recompute_enabled();
803 }
804
805
806 void
807 JvmtiEventControllerPrivate::set_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
808 EC_TRACE(("[%s] # set frame pop - frame=%d",
809 JvmtiTrace::safe_get_thread_name(ets->get_thread()),
810 fpop.frame_number() ));
811
812 ets->get_frame_pops()->set(fpop);
813 recompute_thread_enabled(ets->get_thread()->jvmti_thread_state());
814 }
815
816
817 void
818 JvmtiEventControllerPrivate::clear_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
819 EC_TRACE(("[%s] # clear frame pop - frame=%d",
820 JvmtiTrace::safe_get_thread_name(ets->get_thread()),
821 fpop.frame_number() ));
822
823 ets->get_frame_pops()->clear(fpop);
824 recompute_thread_enabled(ets->get_thread()->jvmti_thread_state());
825 }
826
827
828 void
829 JvmtiEventControllerPrivate::clear_to_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
830 int cleared_cnt = ets->get_frame_pops()->clear_to(fpop);
831
832 EC_TRACE(("[%s] # clear to frame pop - frame=%d, count=%d",
833 JvmtiTrace::safe_get_thread_name(ets->get_thread()),
834 fpop.frame_number(),
835 cleared_cnt ));
836
837 if (cleared_cnt > 0) {
838 recompute_thread_enabled(ets->get_thread()->jvmti_thread_state());
839 }
840 }
841
842 void
843 JvmtiEventControllerPrivate::change_field_watch(jvmtiEvent event_type, bool added) {
844 int *count_addr;
845
846 switch (event_type) {
847 case JVMTI_EVENT_FIELD_MODIFICATION:
848 count_addr = (int *)JvmtiExport::get_field_modification_count_addr();
849 break;
850 case JVMTI_EVENT_FIELD_ACCESS:
851 count_addr = (int *)JvmtiExport::get_field_access_count_addr();
852 break;
853 default:
854 assert(false, "incorrect event");
855 return;
856 }
857
858 EC_TRACE(("[-] # change field watch - %s %s count=%d",
859 event_type==JVMTI_EVENT_FIELD_MODIFICATION? "modification" : "access",
860 added? "add" : "remove",
861 *count_addr));
862
863 if (added) {
864 (*count_addr)++;
865 if (*count_addr == 1) {
866 recompute_enabled();
867 }
868 } else {
869 if (*count_addr > 0) {
870 (*count_addr)--;
871 if (*count_addr == 0) {
872 recompute_enabled();
873 }
874 } else {
875 assert(false, "field watch out of phase");
876 }
877 }
878 }
879
880 void
881 JvmtiEventControllerPrivate::event_init() {
882 assert(JvmtiThreadState_lock->is_locked(), "sanity check");
883
884 if (_initialized) {
885 return;
886 }
887
888 EC_TRACE(("[-] # VM live"));
889
890 #ifdef ASSERT
891 // check that our idea and the spec's idea of threaded events match
892 for (int ei = JVMTI_MIN_EVENT_TYPE_VAL; ei <= JVMTI_MAX_EVENT_TYPE_VAL; ++ei) {
893 jlong bit = JvmtiEventEnabled::bit_for((jvmtiEvent)ei);
894 assert(((THREAD_FILTERED_EVENT_BITS & bit) != 0) == JvmtiUtil::event_threaded(ei),
895 "thread filtered event list does not match");
896 }
897 #endif
898
899 _initialized = true;
900 }
901
902 void
903 JvmtiEventControllerPrivate::vm_start() {
904 // some events are now able to be enabled (phase has changed)
905 JvmtiEventControllerPrivate::recompute_enabled();
906 }
907
908
909 void
910 JvmtiEventControllerPrivate::vm_init() {
911 event_init();
912
913 // all the events are now able to be enabled (phase has changed)
914 JvmtiEventControllerPrivate::recompute_enabled();
915 }
916
917
918 void
919 JvmtiEventControllerPrivate::vm_death() {
920 // events are disabled (phase has changed)
921 JvmtiEventControllerPrivate::recompute_enabled();
922 }
923
924
925 ///////////////////////////////////////////////////////////////
926 //
927 // JvmtiEventController
928 //
929
930 JvmtiEventEnabled JvmtiEventController::_universal_global_event_enabled;
931
932 bool
933 JvmtiEventController::is_global_event(jvmtiEvent event_type) {
934 assert(is_valid_event_type(event_type), "invalid event type");
935 jlong bit_for = ((jlong)1) << (event_type - TOTAL_MIN_EVENT_TYPE_VAL);
936 return((bit_for & GLOBAL_EVENT_BITS)!=0);
937 }
938
939 void
940 JvmtiEventController::set_user_enabled(JvmtiEnvBase *env, JavaThread *thread, jvmtiEvent event_type, bool enabled) {
941 if (Threads::number_of_threads() == 0) {
942 // during early VM start-up locks don't exist, but we are safely single threaded,
943 // call the functionality without holding the JvmtiThreadState_lock.
944 JvmtiEventControllerPrivate::set_user_enabled(env, thread, event_type, enabled);
945 } else {
946 MutexLocker mu(JvmtiThreadState_lock);
947 JvmtiEventControllerPrivate::set_user_enabled(env, thread, event_type, enabled);
948 }
949 }
950
951
952 void
953 JvmtiEventController::set_event_callbacks(JvmtiEnvBase *env,
954 const jvmtiEventCallbacks* callbacks,
955 jint size_of_callbacks) {
956 if (Threads::number_of_threads() == 0) {
957 // during early VM start-up locks don't exist, but we are safely single threaded,
958 // call the functionality without holding the JvmtiThreadState_lock.
959 JvmtiEventControllerPrivate::set_event_callbacks(env, callbacks, size_of_callbacks);
960 } else {
961 MutexLocker mu(JvmtiThreadState_lock);
962 JvmtiEventControllerPrivate::set_event_callbacks(env, callbacks, size_of_callbacks);
963 }
964 }
965
966 void
967 JvmtiEventController::set_extension_event_callback(JvmtiEnvBase *env,
968 jint extension_event_index,
969 jvmtiExtensionEvent callback) {
970 if (Threads::number_of_threads() == 0) {
971 JvmtiEventControllerPrivate::set_extension_event_callback(env, extension_event_index, callback);
972 } else {
973 MutexLocker mu(JvmtiThreadState_lock);
974 JvmtiEventControllerPrivate::set_extension_event_callback(env, extension_event_index, callback);
975 }
976 }
977
978
979
980
981 void
982 JvmtiEventController::set_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
983 MutexLocker mu(SafepointSynchronize::is_at_safepoint() ? NULL : JvmtiThreadState_lock);
984 JvmtiEventControllerPrivate::set_frame_pop(ets, fpop);
985 }
986
987
988 void
989 JvmtiEventController::clear_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
990 MutexLocker mu(SafepointSynchronize::is_at_safepoint() ? NULL : JvmtiThreadState_lock);
991 JvmtiEventControllerPrivate::clear_frame_pop(ets, fpop);
992 }
993
994
995 void
996 JvmtiEventController::clear_to_frame_pop(JvmtiEnvThreadState *ets, JvmtiFramePop fpop) {
997 MutexLocker mu(SafepointSynchronize::is_at_safepoint() ? NULL : JvmtiThreadState_lock);
998 JvmtiEventControllerPrivate::clear_to_frame_pop(ets, fpop);
999 }
1000
1001 void
1002 JvmtiEventController::change_field_watch(jvmtiEvent event_type, bool added) {
1003 MutexLocker mu(JvmtiThreadState_lock);
1004 JvmtiEventControllerPrivate::change_field_watch(event_type, added);
1005 }
1006
1007 void
1008 JvmtiEventController::thread_started(JavaThread *thread) {
1009 // operates only on the current thread
1010 // JvmtiThreadState_lock grabbed only if needed.
1011 JvmtiEventControllerPrivate::thread_started(thread);
1012 }
1013
1014 void
1015 JvmtiEventController::thread_ended(JavaThread *thread) {
1016 // operates only on the current thread
1017 // JvmtiThreadState_lock grabbed only if needed.
1018 JvmtiEventControllerPrivate::thread_ended(thread);
1019 }
1020
1021 void
1022 JvmtiEventController::env_initialize(JvmtiEnvBase *env) {
1023 if (Threads::number_of_threads() == 0) {
1024 // during early VM start-up locks don't exist, but we are safely single threaded,
1025 // call the functionality without holding the JvmtiThreadState_lock.
1026 JvmtiEventControllerPrivate::env_initialize(env);
1027 } else {
1028 MutexLocker mu(JvmtiThreadState_lock);
1029 JvmtiEventControllerPrivate::env_initialize(env);
1030 }
1031 }
1032
1033 void
1034 JvmtiEventController::env_dispose(JvmtiEnvBase *env) {
1035 if (Threads::number_of_threads() == 0) {
1036 // during early VM start-up locks don't exist, but we are safely single threaded,
1037 // call the functionality without holding the JvmtiThreadState_lock.
1038 JvmtiEventControllerPrivate::env_dispose(env);
1039 } else {
1040 MutexLocker mu(JvmtiThreadState_lock);
1041 JvmtiEventControllerPrivate::env_dispose(env);
1042 }
1043 }
1044
1045
1046 void
1047 JvmtiEventController::vm_start() {
1048 if (JvmtiEnvBase::environments_might_exist()) {
1049 MutexLocker mu(JvmtiThreadState_lock);
1050 JvmtiEventControllerPrivate::vm_start();
1051 }
1052 }
1053
1054 void
1055 JvmtiEventController::vm_init() {
1056 if (JvmtiEnvBase::environments_might_exist()) {
1057 MutexLocker mu(JvmtiThreadState_lock);
1058 JvmtiEventControllerPrivate::vm_init();
1059 }
1060 }
1061
1062 void
1063 JvmtiEventController::vm_death() {
1064 if (JvmtiEnvBase::environments_might_exist()) {
1065 MutexLocker mu(JvmtiThreadState_lock);
1066 JvmtiEventControllerPrivate::vm_death();
1067 }
1068 }