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rev 1081 : imported patch indy-cleanup-6893081.patch
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--- old/src/share/vm/runtime/thread.cpp
+++ new/src/share/vm/runtime/thread.cpp
1 1 /*
2 2 * Copyright 1997-2009 Sun Microsystems, Inc. All Rights Reserved.
3 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 4 *
5 5 * This code is free software; you can redistribute it and/or modify it
6 6 * under the terms of the GNU General Public License version 2 only, as
7 7 * published by the Free Software Foundation.
8 8 *
9 9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 12 * version 2 for more details (a copy is included in the LICENSE file that
13 13 * accompanied this code).
14 14 *
15 15 * You should have received a copy of the GNU General Public License version
16 16 * 2 along with this work; if not, write to the Free Software Foundation,
17 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 18 *
19 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 21 * have any questions.
22 22 *
23 23 */
24 24
25 25 # include "incls/_precompiled.incl"
26 26 # include "incls/_thread.cpp.incl"
27 27
28 28 #ifdef DTRACE_ENABLED
29 29
30 30 // Only bother with this argument setup if dtrace is available
31 31
32 32 HS_DTRACE_PROBE_DECL(hotspot, vm__init__begin);
33 33 HS_DTRACE_PROBE_DECL(hotspot, vm__init__end);
34 34 HS_DTRACE_PROBE_DECL5(hotspot, thread__start, char*, intptr_t,
35 35 intptr_t, intptr_t, bool);
36 36 HS_DTRACE_PROBE_DECL5(hotspot, thread__stop, char*, intptr_t,
37 37 intptr_t, intptr_t, bool);
38 38
39 39 #define DTRACE_THREAD_PROBE(probe, javathread) \
40 40 { \
41 41 ResourceMark rm(this); \
42 42 int len = 0; \
43 43 const char* name = (javathread)->get_thread_name(); \
44 44 len = strlen(name); \
45 45 HS_DTRACE_PROBE5(hotspot, thread__##probe, \
46 46 name, len, \
47 47 java_lang_Thread::thread_id((javathread)->threadObj()), \
48 48 (javathread)->osthread()->thread_id(), \
49 49 java_lang_Thread::is_daemon((javathread)->threadObj())); \
50 50 }
51 51
52 52 #else // ndef DTRACE_ENABLED
53 53
54 54 #define DTRACE_THREAD_PROBE(probe, javathread)
55 55
56 56 #endif // ndef DTRACE_ENABLED
57 57
58 58 // Class hierarchy
59 59 // - Thread
60 60 // - VMThread
61 61 // - WatcherThread
62 62 // - ConcurrentMarkSweepThread
63 63 // - JavaThread
64 64 // - CompilerThread
65 65
66 66 // ======= Thread ========
67 67
68 68 // Support for forcing alignment of thread objects for biased locking
69 69 void* Thread::operator new(size_t size) {
70 70 if (UseBiasedLocking) {
71 71 const int alignment = markOopDesc::biased_lock_alignment;
72 72 size_t aligned_size = size + (alignment - sizeof(intptr_t));
73 73 void* real_malloc_addr = CHeapObj::operator new(aligned_size);
74 74 void* aligned_addr = (void*) align_size_up((intptr_t) real_malloc_addr, alignment);
75 75 assert(((uintptr_t) aligned_addr + (uintptr_t) size) <=
76 76 ((uintptr_t) real_malloc_addr + (uintptr_t) aligned_size),
77 77 "JavaThread alignment code overflowed allocated storage");
78 78 if (TraceBiasedLocking) {
79 79 if (aligned_addr != real_malloc_addr)
80 80 tty->print_cr("Aligned thread " INTPTR_FORMAT " to " INTPTR_FORMAT,
81 81 real_malloc_addr, aligned_addr);
82 82 }
83 83 ((Thread*) aligned_addr)->_real_malloc_address = real_malloc_addr;
84 84 return aligned_addr;
85 85 } else {
86 86 return CHeapObj::operator new(size);
87 87 }
88 88 }
89 89
90 90 void Thread::operator delete(void* p) {
91 91 if (UseBiasedLocking) {
92 92 void* real_malloc_addr = ((Thread*) p)->_real_malloc_address;
93 93 CHeapObj::operator delete(real_malloc_addr);
94 94 } else {
95 95 CHeapObj::operator delete(p);
96 96 }
97 97 }
98 98
99 99
100 100 // Base class for all threads: VMThread, WatcherThread, ConcurrentMarkSweepThread,
101 101 // JavaThread
102 102
103 103
104 104 Thread::Thread() {
105 105 // stack
106 106 _stack_base = NULL;
107 107 _stack_size = 0;
108 108 _self_raw_id = 0;
109 109 _lgrp_id = -1;
110 110 _osthread = NULL;
111 111
112 112 // allocated data structures
113 113 set_resource_area(new ResourceArea());
114 114 set_handle_area(new HandleArea(NULL));
115 115 set_active_handles(NULL);
116 116 set_free_handle_block(NULL);
117 117 set_last_handle_mark(NULL);
118 118 set_osthread(NULL);
119 119
120 120 // This initial value ==> never claimed.
121 121 _oops_do_parity = 0;
122 122
123 123 // the handle mark links itself to last_handle_mark
124 124 new HandleMark(this);
125 125
126 126 // plain initialization
127 127 debug_only(_owned_locks = NULL;)
128 128 debug_only(_allow_allocation_count = 0;)
129 129 NOT_PRODUCT(_allow_safepoint_count = 0;)
130 130 NOT_PRODUCT(_skip_gcalot = false;)
131 131 CHECK_UNHANDLED_OOPS_ONLY(_gc_locked_out_count = 0;)
132 132 _jvmti_env_iteration_count = 0;
133 133 _vm_operation_started_count = 0;
134 134 _vm_operation_completed_count = 0;
135 135 _current_pending_monitor = NULL;
136 136 _current_pending_monitor_is_from_java = true;
137 137 _current_waiting_monitor = NULL;
138 138 _num_nested_signal = 0;
139 139 omFreeList = NULL ;
140 140 omFreeCount = 0 ;
141 141 omFreeProvision = 32 ;
142 142
143 143 _SR_lock = new Monitor(Mutex::suspend_resume, "SR_lock", true);
144 144 _suspend_flags = 0;
145 145
146 146 // thread-specific hashCode stream generator state - Marsaglia shift-xor form
147 147 _hashStateX = os::random() ;
148 148 _hashStateY = 842502087 ;
149 149 _hashStateZ = 0x8767 ; // (int)(3579807591LL & 0xffff) ;
150 150 _hashStateW = 273326509 ;
151 151
152 152 _OnTrap = 0 ;
153 153 _schedctl = NULL ;
154 154 _Stalled = 0 ;
155 155 _TypeTag = 0x2BAD ;
156 156
157 157 // Many of the following fields are effectively final - immutable
158 158 // Note that nascent threads can't use the Native Monitor-Mutex
159 159 // construct until the _MutexEvent is initialized ...
160 160 // CONSIDER: instead of using a fixed set of purpose-dedicated ParkEvents
161 161 // we might instead use a stack of ParkEvents that we could provision on-demand.
162 162 // The stack would act as a cache to avoid calls to ParkEvent::Allocate()
163 163 // and ::Release()
164 164 _ParkEvent = ParkEvent::Allocate (this) ;
165 165 _SleepEvent = ParkEvent::Allocate (this) ;
166 166 _MutexEvent = ParkEvent::Allocate (this) ;
167 167 _MuxEvent = ParkEvent::Allocate (this) ;
168 168
169 169 #ifdef CHECK_UNHANDLED_OOPS
170 170 if (CheckUnhandledOops) {
171 171 _unhandled_oops = new UnhandledOops(this);
172 172 }
173 173 #endif // CHECK_UNHANDLED_OOPS
174 174 #ifdef ASSERT
175 175 if (UseBiasedLocking) {
176 176 assert((((uintptr_t) this) & (markOopDesc::biased_lock_alignment - 1)) == 0, "forced alignment of thread object failed");
177 177 assert(this == _real_malloc_address ||
178 178 this == (void*) align_size_up((intptr_t) _real_malloc_address, markOopDesc::biased_lock_alignment),
179 179 "bug in forced alignment of thread objects");
180 180 }
181 181 #endif /* ASSERT */
182 182 }
183 183
184 184 void Thread::initialize_thread_local_storage() {
185 185 // Note: Make sure this method only calls
186 186 // non-blocking operations. Otherwise, it might not work
187 187 // with the thread-startup/safepoint interaction.
188 188
189 189 // During Java thread startup, safepoint code should allow this
190 190 // method to complete because it may need to allocate memory to
191 191 // store information for the new thread.
192 192
193 193 // initialize structure dependent on thread local storage
194 194 ThreadLocalStorage::set_thread(this);
195 195
196 196 // set up any platform-specific state.
197 197 os::initialize_thread();
198 198
199 199 }
200 200
201 201 void Thread::record_stack_base_and_size() {
202 202 set_stack_base(os::current_stack_base());
203 203 set_stack_size(os::current_stack_size());
204 204 }
205 205
206 206
207 207 Thread::~Thread() {
208 208 // Reclaim the objectmonitors from the omFreeList of the moribund thread.
209 209 ObjectSynchronizer::omFlush (this) ;
210 210
211 211 // deallocate data structures
212 212 delete resource_area();
213 213 // since the handle marks are using the handle area, we have to deallocated the root
214 214 // handle mark before deallocating the thread's handle area,
215 215 assert(last_handle_mark() != NULL, "check we have an element");
216 216 delete last_handle_mark();
217 217 assert(last_handle_mark() == NULL, "check we have reached the end");
218 218
219 219 // It's possible we can encounter a null _ParkEvent, etc., in stillborn threads.
220 220 // We NULL out the fields for good hygiene.
221 221 ParkEvent::Release (_ParkEvent) ; _ParkEvent = NULL ;
222 222 ParkEvent::Release (_SleepEvent) ; _SleepEvent = NULL ;
223 223 ParkEvent::Release (_MutexEvent) ; _MutexEvent = NULL ;
224 224 ParkEvent::Release (_MuxEvent) ; _MuxEvent = NULL ;
225 225
226 226 delete handle_area();
227 227
228 228 // osthread() can be NULL, if creation of thread failed.
229 229 if (osthread() != NULL) os::free_thread(osthread());
230 230
231 231 delete _SR_lock;
232 232
233 233 // clear thread local storage if the Thread is deleting itself
234 234 if (this == Thread::current()) {
235 235 ThreadLocalStorage::set_thread(NULL);
236 236 } else {
237 237 // In the case where we're not the current thread, invalidate all the
238 238 // caches in case some code tries to get the current thread or the
239 239 // thread that was destroyed, and gets stale information.
240 240 ThreadLocalStorage::invalidate_all();
241 241 }
242 242 CHECK_UNHANDLED_OOPS_ONLY(if (CheckUnhandledOops) delete unhandled_oops();)
243 243 }
244 244
245 245 // NOTE: dummy function for assertion purpose.
246 246 void Thread::run() {
247 247 ShouldNotReachHere();
248 248 }
249 249
250 250 #ifdef ASSERT
251 251 // Private method to check for dangling thread pointer
252 252 void check_for_dangling_thread_pointer(Thread *thread) {
253 253 assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
254 254 "possibility of dangling Thread pointer");
255 255 }
256 256 #endif
257 257
258 258
259 259 #ifndef PRODUCT
260 260 // Tracing method for basic thread operations
261 261 void Thread::trace(const char* msg, const Thread* const thread) {
262 262 if (!TraceThreadEvents) return;
263 263 ResourceMark rm;
264 264 ThreadCritical tc;
265 265 const char *name = "non-Java thread";
266 266 int prio = -1;
267 267 if (thread->is_Java_thread()
268 268 && !thread->is_Compiler_thread()) {
269 269 // The Threads_lock must be held to get information about
270 270 // this thread but may not be in some situations when
271 271 // tracing thread events.
272 272 bool release_Threads_lock = false;
273 273 if (!Threads_lock->owned_by_self()) {
274 274 Threads_lock->lock();
275 275 release_Threads_lock = true;
276 276 }
277 277 JavaThread* jt = (JavaThread *)thread;
278 278 name = (char *)jt->get_thread_name();
279 279 oop thread_oop = jt->threadObj();
280 280 if (thread_oop != NULL) {
281 281 prio = java_lang_Thread::priority(thread_oop);
282 282 }
283 283 if (release_Threads_lock) {
284 284 Threads_lock->unlock();
285 285 }
286 286 }
287 287 tty->print_cr("Thread::%s " INTPTR_FORMAT " [%lx] %s (prio: %d)", msg, thread, thread->osthread()->thread_id(), name, prio);
288 288 }
289 289 #endif
290 290
291 291
292 292 ThreadPriority Thread::get_priority(const Thread* const thread) {
293 293 trace("get priority", thread);
294 294 ThreadPriority priority;
295 295 // Can return an error!
296 296 (void)os::get_priority(thread, priority);
297 297 assert(MinPriority <= priority && priority <= MaxPriority, "non-Java priority found");
298 298 return priority;
299 299 }
300 300
301 301 void Thread::set_priority(Thread* thread, ThreadPriority priority) {
302 302 trace("set priority", thread);
303 303 debug_only(check_for_dangling_thread_pointer(thread);)
304 304 // Can return an error!
305 305 (void)os::set_priority(thread, priority);
306 306 }
307 307
308 308
309 309 void Thread::start(Thread* thread) {
310 310 trace("start", thread);
311 311 // Start is different from resume in that its safety is guaranteed by context or
312 312 // being called from a Java method synchronized on the Thread object.
313 313 if (!DisableStartThread) {
314 314 if (thread->is_Java_thread()) {
315 315 // Initialize the thread state to RUNNABLE before starting this thread.
316 316 // Can not set it after the thread started because we do not know the
317 317 // exact thread state at that time. It could be in MONITOR_WAIT or
318 318 // in SLEEPING or some other state.
319 319 java_lang_Thread::set_thread_status(((JavaThread*)thread)->threadObj(),
320 320 java_lang_Thread::RUNNABLE);
321 321 }
322 322 os::start_thread(thread);
323 323 }
324 324 }
325 325
326 326 // Enqueue a VM_Operation to do the job for us - sometime later
327 327 void Thread::send_async_exception(oop java_thread, oop java_throwable) {
328 328 VM_ThreadStop* vm_stop = new VM_ThreadStop(java_thread, java_throwable);
329 329 VMThread::execute(vm_stop);
330 330 }
331 331
332 332
333 333 //
334 334 // Check if an external suspend request has completed (or has been
335 335 // cancelled). Returns true if the thread is externally suspended and
336 336 // false otherwise.
337 337 //
338 338 // The bits parameter returns information about the code path through
339 339 // the routine. Useful for debugging:
340 340 //
341 341 // set in is_ext_suspend_completed():
342 342 // 0x00000001 - routine was entered
343 343 // 0x00000010 - routine return false at end
344 344 // 0x00000100 - thread exited (return false)
345 345 // 0x00000200 - suspend request cancelled (return false)
346 346 // 0x00000400 - thread suspended (return true)
347 347 // 0x00001000 - thread is in a suspend equivalent state (return true)
348 348 // 0x00002000 - thread is native and walkable (return true)
349 349 // 0x00004000 - thread is native_trans and walkable (needed retry)
350 350 //
351 351 // set in wait_for_ext_suspend_completion():
352 352 // 0x00010000 - routine was entered
353 353 // 0x00020000 - suspend request cancelled before loop (return false)
354 354 // 0x00040000 - thread suspended before loop (return true)
355 355 // 0x00080000 - suspend request cancelled in loop (return false)
356 356 // 0x00100000 - thread suspended in loop (return true)
357 357 // 0x00200000 - suspend not completed during retry loop (return false)
358 358 //
359 359
360 360 // Helper class for tracing suspend wait debug bits.
361 361 //
362 362 // 0x00000100 indicates that the target thread exited before it could
363 363 // self-suspend which is not a wait failure. 0x00000200, 0x00020000 and
364 364 // 0x00080000 each indicate a cancelled suspend request so they don't
365 365 // count as wait failures either.
366 366 #define DEBUG_FALSE_BITS (0x00000010 | 0x00200000)
367 367
368 368 class TraceSuspendDebugBits : public StackObj {
369 369 private:
370 370 JavaThread * jt;
371 371 bool is_wait;
372 372 bool called_by_wait; // meaningful when !is_wait
373 373 uint32_t * bits;
374 374
375 375 public:
376 376 TraceSuspendDebugBits(JavaThread *_jt, bool _is_wait, bool _called_by_wait,
377 377 uint32_t *_bits) {
378 378 jt = _jt;
379 379 is_wait = _is_wait;
380 380 called_by_wait = _called_by_wait;
381 381 bits = _bits;
382 382 }
383 383
384 384 ~TraceSuspendDebugBits() {
385 385 if (!is_wait) {
386 386 #if 1
387 387 // By default, don't trace bits for is_ext_suspend_completed() calls.
388 388 // That trace is very chatty.
389 389 return;
390 390 #else
391 391 if (!called_by_wait) {
392 392 // If tracing for is_ext_suspend_completed() is enabled, then only
393 393 // trace calls to it from wait_for_ext_suspend_completion()
394 394 return;
395 395 }
396 396 #endif
397 397 }
398 398
399 399 if (AssertOnSuspendWaitFailure || TraceSuspendWaitFailures) {
400 400 if (bits != NULL && (*bits & DEBUG_FALSE_BITS) != 0) {
401 401 MutexLocker ml(Threads_lock); // needed for get_thread_name()
402 402 ResourceMark rm;
403 403
404 404 tty->print_cr(
405 405 "Failed wait_for_ext_suspend_completion(thread=%s, debug_bits=%x)",
406 406 jt->get_thread_name(), *bits);
407 407
408 408 guarantee(!AssertOnSuspendWaitFailure, "external suspend wait failed");
409 409 }
410 410 }
411 411 }
412 412 };
413 413 #undef DEBUG_FALSE_BITS
414 414
415 415
416 416 bool JavaThread::is_ext_suspend_completed(bool called_by_wait, int delay, uint32_t *bits) {
417 417 TraceSuspendDebugBits tsdb(this, false /* !is_wait */, called_by_wait, bits);
418 418
419 419 bool did_trans_retry = false; // only do thread_in_native_trans retry once
420 420 bool do_trans_retry; // flag to force the retry
421 421
422 422 *bits |= 0x00000001;
423 423
424 424 do {
425 425 do_trans_retry = false;
426 426
427 427 if (is_exiting()) {
428 428 // Thread is in the process of exiting. This is always checked
429 429 // first to reduce the risk of dereferencing a freed JavaThread.
430 430 *bits |= 0x00000100;
431 431 return false;
432 432 }
433 433
434 434 if (!is_external_suspend()) {
435 435 // Suspend request is cancelled. This is always checked before
436 436 // is_ext_suspended() to reduce the risk of a rogue resume
437 437 // confusing the thread that made the suspend request.
438 438 *bits |= 0x00000200;
439 439 return false;
440 440 }
441 441
442 442 if (is_ext_suspended()) {
443 443 // thread is suspended
444 444 *bits |= 0x00000400;
445 445 return true;
446 446 }
447 447
448 448 // Now that we no longer do hard suspends of threads running
449 449 // native code, the target thread can be changing thread state
450 450 // while we are in this routine:
451 451 //
452 452 // _thread_in_native -> _thread_in_native_trans -> _thread_blocked
453 453 //
454 454 // We save a copy of the thread state as observed at this moment
455 455 // and make our decision about suspend completeness based on the
456 456 // copy. This closes the race where the thread state is seen as
457 457 // _thread_in_native_trans in the if-thread_blocked check, but is
458 458 // seen as _thread_blocked in if-thread_in_native_trans check.
459 459 JavaThreadState save_state = thread_state();
460 460
461 461 if (save_state == _thread_blocked && is_suspend_equivalent()) {
462 462 // If the thread's state is _thread_blocked and this blocking
463 463 // condition is known to be equivalent to a suspend, then we can
464 464 // consider the thread to be externally suspended. This means that
465 465 // the code that sets _thread_blocked has been modified to do
466 466 // self-suspension if the blocking condition releases. We also
467 467 // used to check for CONDVAR_WAIT here, but that is now covered by
468 468 // the _thread_blocked with self-suspension check.
469 469 //
470 470 // Return true since we wouldn't be here unless there was still an
471 471 // external suspend request.
472 472 *bits |= 0x00001000;
473 473 return true;
474 474 } else if (save_state == _thread_in_native && frame_anchor()->walkable()) {
475 475 // Threads running native code will self-suspend on native==>VM/Java
476 476 // transitions. If its stack is walkable (should always be the case
477 477 // unless this function is called before the actual java_suspend()
478 478 // call), then the wait is done.
479 479 *bits |= 0x00002000;
480 480 return true;
481 481 } else if (!called_by_wait && !did_trans_retry &&
482 482 save_state == _thread_in_native_trans &&
483 483 frame_anchor()->walkable()) {
484 484 // The thread is transitioning from thread_in_native to another
485 485 // thread state. check_safepoint_and_suspend_for_native_trans()
486 486 // will force the thread to self-suspend. If it hasn't gotten
487 487 // there yet we may have caught the thread in-between the native
488 488 // code check above and the self-suspend. Lucky us. If we were
489 489 // called by wait_for_ext_suspend_completion(), then it
490 490 // will be doing the retries so we don't have to.
491 491 //
492 492 // Since we use the saved thread state in the if-statement above,
493 493 // there is a chance that the thread has already transitioned to
494 494 // _thread_blocked by the time we get here. In that case, we will
495 495 // make a single unnecessary pass through the logic below. This
496 496 // doesn't hurt anything since we still do the trans retry.
497 497
498 498 *bits |= 0x00004000;
499 499
500 500 // Once the thread leaves thread_in_native_trans for another
501 501 // thread state, we break out of this retry loop. We shouldn't
502 502 // need this flag to prevent us from getting back here, but
503 503 // sometimes paranoia is good.
504 504 did_trans_retry = true;
505 505
506 506 // We wait for the thread to transition to a more usable state.
507 507 for (int i = 1; i <= SuspendRetryCount; i++) {
508 508 // We used to do an "os::yield_all(i)" call here with the intention
509 509 // that yielding would increase on each retry. However, the parameter
510 510 // is ignored on Linux which means the yield didn't scale up. Waiting
511 511 // on the SR_lock below provides a much more predictable scale up for
512 512 // the delay. It also provides a simple/direct point to check for any
513 513 // safepoint requests from the VMThread
514 514
515 515 // temporarily drops SR_lock while doing wait with safepoint check
516 516 // (if we're a JavaThread - the WatcherThread can also call this)
517 517 // and increase delay with each retry
518 518 SR_lock()->wait(!Thread::current()->is_Java_thread(), i * delay);
519 519
520 520 // check the actual thread state instead of what we saved above
521 521 if (thread_state() != _thread_in_native_trans) {
522 522 // the thread has transitioned to another thread state so
523 523 // try all the checks (except this one) one more time.
524 524 do_trans_retry = true;
525 525 break;
526 526 }
527 527 } // end retry loop
528 528
529 529
530 530 }
531 531 } while (do_trans_retry);
532 532
533 533 *bits |= 0x00000010;
534 534 return false;
535 535 }
536 536
537 537 //
538 538 // Wait for an external suspend request to complete (or be cancelled).
539 539 // Returns true if the thread is externally suspended and false otherwise.
540 540 //
541 541 bool JavaThread::wait_for_ext_suspend_completion(int retries, int delay,
542 542 uint32_t *bits) {
543 543 TraceSuspendDebugBits tsdb(this, true /* is_wait */,
544 544 false /* !called_by_wait */, bits);
545 545
546 546 // local flag copies to minimize SR_lock hold time
547 547 bool is_suspended;
548 548 bool pending;
549 549 uint32_t reset_bits;
550 550
551 551 // set a marker so is_ext_suspend_completed() knows we are the caller
552 552 *bits |= 0x00010000;
553 553
554 554 // We use reset_bits to reinitialize the bits value at the top of
555 555 // each retry loop. This allows the caller to make use of any
556 556 // unused bits for their own marking purposes.
557 557 reset_bits = *bits;
558 558
559 559 {
560 560 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
561 561 is_suspended = is_ext_suspend_completed(true /* called_by_wait */,
562 562 delay, bits);
563 563 pending = is_external_suspend();
564 564 }
565 565 // must release SR_lock to allow suspension to complete
566 566
567 567 if (!pending) {
568 568 // A cancelled suspend request is the only false return from
569 569 // is_ext_suspend_completed() that keeps us from entering the
570 570 // retry loop.
571 571 *bits |= 0x00020000;
572 572 return false;
573 573 }
574 574
575 575 if (is_suspended) {
576 576 *bits |= 0x00040000;
577 577 return true;
578 578 }
579 579
580 580 for (int i = 1; i <= retries; i++) {
581 581 *bits = reset_bits; // reinit to only track last retry
582 582
583 583 // We used to do an "os::yield_all(i)" call here with the intention
584 584 // that yielding would increase on each retry. However, the parameter
585 585 // is ignored on Linux which means the yield didn't scale up. Waiting
586 586 // on the SR_lock below provides a much more predictable scale up for
587 587 // the delay. It also provides a simple/direct point to check for any
588 588 // safepoint requests from the VMThread
589 589
590 590 {
591 591 MutexLocker ml(SR_lock());
592 592 // wait with safepoint check (if we're a JavaThread - the WatcherThread
593 593 // can also call this) and increase delay with each retry
594 594 SR_lock()->wait(!Thread::current()->is_Java_thread(), i * delay);
595 595
596 596 is_suspended = is_ext_suspend_completed(true /* called_by_wait */,
597 597 delay, bits);
598 598
599 599 // It is possible for the external suspend request to be cancelled
600 600 // (by a resume) before the actual suspend operation is completed.
601 601 // Refresh our local copy to see if we still need to wait.
602 602 pending = is_external_suspend();
603 603 }
604 604
605 605 if (!pending) {
606 606 // A cancelled suspend request is the only false return from
607 607 // is_ext_suspend_completed() that keeps us from staying in the
608 608 // retry loop.
609 609 *bits |= 0x00080000;
610 610 return false;
611 611 }
612 612
613 613 if (is_suspended) {
614 614 *bits |= 0x00100000;
615 615 return true;
616 616 }
617 617 } // end retry loop
618 618
619 619 // thread did not suspend after all our retries
620 620 *bits |= 0x00200000;
621 621 return false;
622 622 }
623 623
624 624 #ifndef PRODUCT
625 625 void JavaThread::record_jump(address target, address instr, const char* file, int line) {
626 626
627 627 // This should not need to be atomic as the only way for simultaneous
628 628 // updates is via interrupts. Even then this should be rare or non-existant
629 629 // and we don't care that much anyway.
630 630
631 631 int index = _jmp_ring_index;
632 632 _jmp_ring_index = (index + 1 ) & (jump_ring_buffer_size - 1);
633 633 _jmp_ring[index]._target = (intptr_t) target;
634 634 _jmp_ring[index]._instruction = (intptr_t) instr;
635 635 _jmp_ring[index]._file = file;
636 636 _jmp_ring[index]._line = line;
637 637 }
638 638 #endif /* PRODUCT */
639 639
640 640 // Called by flat profiler
641 641 // Callers have already called wait_for_ext_suspend_completion
642 642 // The assertion for that is currently too complex to put here:
643 643 bool JavaThread::profile_last_Java_frame(frame* _fr) {
644 644 bool gotframe = false;
645 645 // self suspension saves needed state.
646 646 if (has_last_Java_frame() && _anchor.walkable()) {
647 647 *_fr = pd_last_frame();
648 648 gotframe = true;
649 649 }
650 650 return gotframe;
651 651 }
652 652
653 653 void Thread::interrupt(Thread* thread) {
654 654 trace("interrupt", thread);
655 655 debug_only(check_for_dangling_thread_pointer(thread);)
656 656 os::interrupt(thread);
657 657 }
658 658
659 659 bool Thread::is_interrupted(Thread* thread, bool clear_interrupted) {
660 660 trace("is_interrupted", thread);
661 661 debug_only(check_for_dangling_thread_pointer(thread);)
662 662 // Note: If clear_interrupted==false, this simply fetches and
663 663 // returns the value of the field osthread()->interrupted().
664 664 return os::is_interrupted(thread, clear_interrupted);
665 665 }
666 666
667 667
668 668 // GC Support
669 669 bool Thread::claim_oops_do_par_case(int strong_roots_parity) {
670 670 jint thread_parity = _oops_do_parity;
671 671 if (thread_parity != strong_roots_parity) {
672 672 jint res = Atomic::cmpxchg(strong_roots_parity, &_oops_do_parity, thread_parity);
673 673 if (res == thread_parity) return true;
674 674 else {
675 675 guarantee(res == strong_roots_parity, "Or else what?");
676 676 assert(SharedHeap::heap()->n_par_threads() > 0,
677 677 "Should only fail when parallel.");
678 678 return false;
679 679 }
680 680 }
681 681 assert(SharedHeap::heap()->n_par_threads() > 0,
682 682 "Should only fail when parallel.");
683 683 return false;
684 684 }
685 685
686 686 void Thread::oops_do(OopClosure* f, CodeBlobClosure* cf) {
687 687 active_handles()->oops_do(f);
688 688 // Do oop for ThreadShadow
689 689 f->do_oop((oop*)&_pending_exception);
690 690 handle_area()->oops_do(f);
691 691 }
692 692
693 693 void Thread::nmethods_do(CodeBlobClosure* cf) {
694 694 // no nmethods in a generic thread...
695 695 }
696 696
697 697 void Thread::print_on(outputStream* st) const {
698 698 // get_priority assumes osthread initialized
699 699 if (osthread() != NULL) {
700 700 st->print("prio=%d tid=" INTPTR_FORMAT " ", get_priority(this), this);
701 701 osthread()->print_on(st);
702 702 }
703 703 debug_only(if (WizardMode) print_owned_locks_on(st);)
704 704 }
705 705
706 706 // Thread::print_on_error() is called by fatal error handler. Don't use
707 707 // any lock or allocate memory.
708 708 void Thread::print_on_error(outputStream* st, char* buf, int buflen) const {
709 709 if (is_VM_thread()) st->print("VMThread");
710 710 else if (is_Compiler_thread()) st->print("CompilerThread");
711 711 else if (is_Java_thread()) st->print("JavaThread");
712 712 else if (is_GC_task_thread()) st->print("GCTaskThread");
713 713 else if (is_Watcher_thread()) st->print("WatcherThread");
714 714 else if (is_ConcurrentGC_thread()) st->print("ConcurrentGCThread");
715 715 else st->print("Thread");
716 716
717 717 st->print(" [stack: " PTR_FORMAT "," PTR_FORMAT "]",
718 718 _stack_base - _stack_size, _stack_base);
719 719
720 720 if (osthread()) {
721 721 st->print(" [id=%d]", osthread()->thread_id());
722 722 }
723 723 }
724 724
725 725 #ifdef ASSERT
726 726 void Thread::print_owned_locks_on(outputStream* st) const {
727 727 Monitor *cur = _owned_locks;
728 728 if (cur == NULL) {
729 729 st->print(" (no locks) ");
730 730 } else {
731 731 st->print_cr(" Locks owned:");
732 732 while(cur) {
733 733 cur->print_on(st);
734 734 cur = cur->next();
735 735 }
736 736 }
737 737 }
738 738
739 739 static int ref_use_count = 0;
740 740
741 741 bool Thread::owns_locks_but_compiled_lock() const {
742 742 for(Monitor *cur = _owned_locks; cur; cur = cur->next()) {
743 743 if (cur != Compile_lock) return true;
744 744 }
745 745 return false;
746 746 }
747 747
748 748
749 749 #endif
750 750
751 751 #ifndef PRODUCT
752 752
753 753 // The flag: potential_vm_operation notifies if this particular safepoint state could potential
754 754 // invoke the vm-thread (i.e., and oop allocation). In that case, we also have to make sure that
755 755 // no threads which allow_vm_block's are held
756 756 void Thread::check_for_valid_safepoint_state(bool potential_vm_operation) {
757 757 // Check if current thread is allowed to block at a safepoint
758 758 if (!(_allow_safepoint_count == 0))
759 759 fatal("Possible safepoint reached by thread that does not allow it");
760 760 if (is_Java_thread() && ((JavaThread*)this)->thread_state() != _thread_in_vm) {
761 761 fatal("LEAF method calling lock?");
762 762 }
763 763
764 764 #ifdef ASSERT
765 765 if (potential_vm_operation && is_Java_thread()
766 766 && !Universe::is_bootstrapping()) {
767 767 // Make sure we do not hold any locks that the VM thread also uses.
768 768 // This could potentially lead to deadlocks
769 769 for(Monitor *cur = _owned_locks; cur; cur = cur->next()) {
770 770 // Threads_lock is special, since the safepoint synchronization will not start before this is
771 771 // acquired. Hence, a JavaThread cannot be holding it at a safepoint. So is VMOperationRequest_lock,
772 772 // since it is used to transfer control between JavaThreads and the VMThread
773 773 // Do not *exclude* any locks unless you are absolutly sure it is correct. Ask someone else first!
774 774 if ( (cur->allow_vm_block() &&
775 775 cur != Threads_lock &&
776 776 cur != Compile_lock && // Temporary: should not be necessary when we get spearate compilation
777 777 cur != VMOperationRequest_lock &&
778 778 cur != VMOperationQueue_lock) ||
779 779 cur->rank() == Mutex::special) {
780 780 warning("Thread holding lock at safepoint that vm can block on: %s", cur->name());
781 781 }
782 782 }
783 783 }
784 784
785 785 if (GCALotAtAllSafepoints) {
786 786 // We could enter a safepoint here and thus have a gc
787 787 InterfaceSupport::check_gc_alot();
788 788 }
789 789 #endif
790 790 }
791 791 #endif
792 792
793 793 bool Thread::is_in_stack(address adr) const {
794 794 assert(Thread::current() == this, "is_in_stack can only be called from current thread");
795 795 address end = os::current_stack_pointer();
796 796 if (stack_base() >= adr && adr >= end) return true;
797 797
798 798 return false;
799 799 }
800 800
801 801
802 802 // We had to move these methods here, because vm threads get into ObjectSynchronizer::enter
803 803 // However, there is a note in JavaThread::is_lock_owned() about the VM threads not being
804 804 // used for compilation in the future. If that change is made, the need for these methods
805 805 // should be revisited, and they should be removed if possible.
806 806
807 807 bool Thread::is_lock_owned(address adr) const {
808 808 return (_stack_base >= adr && adr >= (_stack_base - _stack_size));
809 809 }
810 810
811 811 bool Thread::set_as_starting_thread() {
812 812 // NOTE: this must be called inside the main thread.
813 813 return os::create_main_thread((JavaThread*)this);
814 814 }
815 815
816 816 static void initialize_class(symbolHandle class_name, TRAPS) {
817 817 klassOop klass = SystemDictionary::resolve_or_fail(class_name, true, CHECK);
818 818 instanceKlass::cast(klass)->initialize(CHECK);
819 819 }
820 820
821 821
822 822 // Creates the initial ThreadGroup
823 823 static Handle create_initial_thread_group(TRAPS) {
824 824 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_ThreadGroup(), true, CHECK_NH);
825 825 instanceKlassHandle klass (THREAD, k);
826 826
827 827 Handle system_instance = klass->allocate_instance_handle(CHECK_NH);
828 828 {
829 829 JavaValue result(T_VOID);
830 830 JavaCalls::call_special(&result,
831 831 system_instance,
832 832 klass,
833 833 vmSymbolHandles::object_initializer_name(),
834 834 vmSymbolHandles::void_method_signature(),
835 835 CHECK_NH);
836 836 }
837 837 Universe::set_system_thread_group(system_instance());
838 838
839 839 Handle main_instance = klass->allocate_instance_handle(CHECK_NH);
840 840 {
841 841 JavaValue result(T_VOID);
842 842 Handle string = java_lang_String::create_from_str("main", CHECK_NH);
843 843 JavaCalls::call_special(&result,
844 844 main_instance,
845 845 klass,
846 846 vmSymbolHandles::object_initializer_name(),
847 847 vmSymbolHandles::threadgroup_string_void_signature(),
848 848 system_instance,
849 849 string,
850 850 CHECK_NH);
851 851 }
852 852 return main_instance;
853 853 }
854 854
855 855 // Creates the initial Thread
856 856 static oop create_initial_thread(Handle thread_group, JavaThread* thread, TRAPS) {
857 857 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_Thread(), true, CHECK_NULL);
858 858 instanceKlassHandle klass (THREAD, k);
859 859 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK_NULL);
860 860
861 861 java_lang_Thread::set_thread(thread_oop(), thread);
862 862 java_lang_Thread::set_priority(thread_oop(), NormPriority);
863 863 thread->set_threadObj(thread_oop());
864 864
865 865 Handle string = java_lang_String::create_from_str("main", CHECK_NULL);
866 866
867 867 JavaValue result(T_VOID);
868 868 JavaCalls::call_special(&result, thread_oop,
869 869 klass,
870 870 vmSymbolHandles::object_initializer_name(),
871 871 vmSymbolHandles::threadgroup_string_void_signature(),
872 872 thread_group,
873 873 string,
874 874 CHECK_NULL);
875 875 return thread_oop();
876 876 }
877 877
878 878 static void call_initializeSystemClass(TRAPS) {
879 879 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_System(), true, CHECK);
880 880 instanceKlassHandle klass (THREAD, k);
881 881
882 882 JavaValue result(T_VOID);
883 883 JavaCalls::call_static(&result, klass, vmSymbolHandles::initializeSystemClass_name(),
884 884 vmSymbolHandles::void_method_signature(), CHECK);
885 885 }
886 886
887 887 static void reset_vm_info_property(TRAPS) {
888 888 // the vm info string
889 889 ResourceMark rm(THREAD);
890 890 const char *vm_info = VM_Version::vm_info_string();
891 891
892 892 // java.lang.System class
893 893 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_System(), true, CHECK);
894 894 instanceKlassHandle klass (THREAD, k);
895 895
896 896 // setProperty arguments
897 897 Handle key_str = java_lang_String::create_from_str("java.vm.info", CHECK);
898 898 Handle value_str = java_lang_String::create_from_str(vm_info, CHECK);
899 899
900 900 // return value
901 901 JavaValue r(T_OBJECT);
902 902
903 903 // public static String setProperty(String key, String value);
904 904 JavaCalls::call_static(&r,
905 905 klass,
906 906 vmSymbolHandles::setProperty_name(),
907 907 vmSymbolHandles::string_string_string_signature(),
908 908 key_str,
909 909 value_str,
910 910 CHECK);
911 911 }
912 912
913 913
914 914 void JavaThread::allocate_threadObj(Handle thread_group, char* thread_name, bool daemon, TRAPS) {
915 915 assert(thread_group.not_null(), "thread group should be specified");
916 916 assert(threadObj() == NULL, "should only create Java thread object once");
917 917
918 918 klassOop k = SystemDictionary::resolve_or_fail(vmSymbolHandles::java_lang_Thread(), true, CHECK);
919 919 instanceKlassHandle klass (THREAD, k);
920 920 instanceHandle thread_oop = klass->allocate_instance_handle(CHECK);
921 921
922 922 java_lang_Thread::set_thread(thread_oop(), this);
923 923 java_lang_Thread::set_priority(thread_oop(), NormPriority);
924 924 set_threadObj(thread_oop());
925 925
926 926 JavaValue result(T_VOID);
927 927 if (thread_name != NULL) {
928 928 Handle name = java_lang_String::create_from_str(thread_name, CHECK);
929 929 // Thread gets assigned specified name and null target
930 930 JavaCalls::call_special(&result,
931 931 thread_oop,
932 932 klass,
933 933 vmSymbolHandles::object_initializer_name(),
934 934 vmSymbolHandles::threadgroup_string_void_signature(),
935 935 thread_group, // Argument 1
936 936 name, // Argument 2
937 937 THREAD);
938 938 } else {
939 939 // Thread gets assigned name "Thread-nnn" and null target
940 940 // (java.lang.Thread doesn't have a constructor taking only a ThreadGroup argument)
941 941 JavaCalls::call_special(&result,
942 942 thread_oop,
943 943 klass,
944 944 vmSymbolHandles::object_initializer_name(),
945 945 vmSymbolHandles::threadgroup_runnable_void_signature(),
946 946 thread_group, // Argument 1
947 947 Handle(), // Argument 2
948 948 THREAD);
949 949 }
950 950
951 951
952 952 if (daemon) {
953 953 java_lang_Thread::set_daemon(thread_oop());
954 954 }
955 955
956 956 if (HAS_PENDING_EXCEPTION) {
957 957 return;
958 958 }
959 959
960 960 KlassHandle group(this, SystemDictionary::threadGroup_klass());
961 961 Handle threadObj(this, this->threadObj());
962 962
963 963 JavaCalls::call_special(&result,
964 964 thread_group,
965 965 group,
966 966 vmSymbolHandles::add_method_name(),
967 967 vmSymbolHandles::thread_void_signature(),
968 968 threadObj, // Arg 1
969 969 THREAD);
970 970
971 971
972 972 }
973 973
974 974 // NamedThread -- non-JavaThread subclasses with multiple
975 975 // uniquely named instances should derive from this.
976 976 NamedThread::NamedThread() : Thread() {
977 977 _name = NULL;
978 978 }
979 979
980 980 NamedThread::~NamedThread() {
981 981 if (_name != NULL) {
982 982 FREE_C_HEAP_ARRAY(char, _name);
983 983 _name = NULL;
984 984 }
985 985 }
986 986
987 987 void NamedThread::set_name(const char* format, ...) {
988 988 guarantee(_name == NULL, "Only get to set name once.");
989 989 _name = NEW_C_HEAP_ARRAY(char, max_name_len);
990 990 guarantee(_name != NULL, "alloc failure");
991 991 va_list ap;
992 992 va_start(ap, format);
993 993 jio_vsnprintf(_name, max_name_len, format, ap);
994 994 va_end(ap);
995 995 }
996 996
997 997 // ======= WatcherThread ========
998 998
999 999 // The watcher thread exists to simulate timer interrupts. It should
1000 1000 // be replaced by an abstraction over whatever native support for
1001 1001 // timer interrupts exists on the platform.
1002 1002
1003 1003 WatcherThread* WatcherThread::_watcher_thread = NULL;
1004 1004 bool WatcherThread::_should_terminate = false;
1005 1005
1006 1006 WatcherThread::WatcherThread() : Thread() {
1007 1007 assert(watcher_thread() == NULL, "we can only allocate one WatcherThread");
1008 1008 if (os::create_thread(this, os::watcher_thread)) {
1009 1009 _watcher_thread = this;
1010 1010
1011 1011 // Set the watcher thread to the highest OS priority which should not be
1012 1012 // used, unless a Java thread with priority java.lang.Thread.MAX_PRIORITY
1013 1013 // is created. The only normal thread using this priority is the reference
1014 1014 // handler thread, which runs for very short intervals only.
1015 1015 // If the VMThread's priority is not lower than the WatcherThread profiling
1016 1016 // will be inaccurate.
1017 1017 os::set_priority(this, MaxPriority);
1018 1018 if (!DisableStartThread) {
1019 1019 os::start_thread(this);
1020 1020 }
1021 1021 }
1022 1022 }
1023 1023
1024 1024 void WatcherThread::run() {
1025 1025 assert(this == watcher_thread(), "just checking");
1026 1026
1027 1027 this->record_stack_base_and_size();
1028 1028 this->initialize_thread_local_storage();
1029 1029 this->set_active_handles(JNIHandleBlock::allocate_block());
1030 1030 while(!_should_terminate) {
1031 1031 assert(watcher_thread() == Thread::current(), "thread consistency check");
1032 1032 assert(watcher_thread() == this, "thread consistency check");
1033 1033
1034 1034 // Calculate how long it'll be until the next PeriodicTask work
1035 1035 // should be done, and sleep that amount of time.
1036 1036 const size_t time_to_wait = PeriodicTask::time_to_wait();
1037 1037 os::sleep(this, time_to_wait, false);
1038 1038
1039 1039 if (is_error_reported()) {
1040 1040 // A fatal error has happened, the error handler(VMError::report_and_die)
1041 1041 // should abort JVM after creating an error log file. However in some
1042 1042 // rare cases, the error handler itself might deadlock. Here we try to
1043 1043 // kill JVM if the fatal error handler fails to abort in 2 minutes.
1044 1044 //
1045 1045 // This code is in WatcherThread because WatcherThread wakes up
1046 1046 // periodically so the fatal error handler doesn't need to do anything;
1047 1047 // also because the WatcherThread is less likely to crash than other
1048 1048 // threads.
1049 1049
1050 1050 for (;;) {
1051 1051 if (!ShowMessageBoxOnError
1052 1052 && (OnError == NULL || OnError[0] == '\0')
1053 1053 && Arguments::abort_hook() == NULL) {
1054 1054 os::sleep(this, 2 * 60 * 1000, false);
1055 1055 fdStream err(defaultStream::output_fd());
1056 1056 err.print_raw_cr("# [ timer expired, abort... ]");
1057 1057 // skip atexit/vm_exit/vm_abort hooks
1058 1058 os::die();
1059 1059 }
1060 1060
1061 1061 // Wake up 5 seconds later, the fatal handler may reset OnError or
1062 1062 // ShowMessageBoxOnError when it is ready to abort.
1063 1063 os::sleep(this, 5 * 1000, false);
1064 1064 }
1065 1065 }
1066 1066
1067 1067 PeriodicTask::real_time_tick(time_to_wait);
1068 1068
1069 1069 // If we have no more tasks left due to dynamic disenrollment,
1070 1070 // shut down the thread since we don't currently support dynamic enrollment
1071 1071 if (PeriodicTask::num_tasks() == 0) {
1072 1072 _should_terminate = true;
1073 1073 }
1074 1074 }
1075 1075
1076 1076 // Signal that it is terminated
1077 1077 {
1078 1078 MutexLockerEx mu(Terminator_lock, Mutex::_no_safepoint_check_flag);
1079 1079 _watcher_thread = NULL;
1080 1080 Terminator_lock->notify();
1081 1081 }
1082 1082
1083 1083 // Thread destructor usually does this..
1084 1084 ThreadLocalStorage::set_thread(NULL);
1085 1085 }
1086 1086
1087 1087 void WatcherThread::start() {
1088 1088 if (watcher_thread() == NULL) {
1089 1089 _should_terminate = false;
1090 1090 // Create the single instance of WatcherThread
1091 1091 new WatcherThread();
1092 1092 }
1093 1093 }
1094 1094
1095 1095 void WatcherThread::stop() {
1096 1096 // it is ok to take late safepoints here, if needed
1097 1097 MutexLocker mu(Terminator_lock);
1098 1098 _should_terminate = true;
1099 1099 while(watcher_thread() != NULL) {
1100 1100 // This wait should make safepoint checks, wait without a timeout,
1101 1101 // and wait as a suspend-equivalent condition.
1102 1102 //
1103 1103 // Note: If the FlatProfiler is running, then this thread is waiting
1104 1104 // for the WatcherThread to terminate and the WatcherThread, via the
1105 1105 // FlatProfiler task, is waiting for the external suspend request on
1106 1106 // this thread to complete. wait_for_ext_suspend_completion() will
1107 1107 // eventually timeout, but that takes time. Making this wait a
1108 1108 // suspend-equivalent condition solves that timeout problem.
1109 1109 //
1110 1110 Terminator_lock->wait(!Mutex::_no_safepoint_check_flag, 0,
1111 1111 Mutex::_as_suspend_equivalent_flag);
1112 1112 }
1113 1113 }
1114 1114
1115 1115 void WatcherThread::print_on(outputStream* st) const {
1116 1116 st->print("\"%s\" ", name());
1117 1117 Thread::print_on(st);
1118 1118 st->cr();
1119 1119 }
1120 1120
1121 1121 // ======= JavaThread ========
1122 1122
1123 1123 // A JavaThread is a normal Java thread
1124 1124
1125 1125 void JavaThread::initialize() {
1126 1126 // Initialize fields
1127 1127
1128 1128 // Set the claimed par_id to -1 (ie not claiming any par_ids)
1129 1129 set_claimed_par_id(-1);
1130 1130
1131 1131 set_saved_exception_pc(NULL);
1132 1132 set_threadObj(NULL);
1133 1133 _anchor.clear();
1134 1134 set_entry_point(NULL);
1135 1135 set_jni_functions(jni_functions());
1136 1136 set_callee_target(NULL);
1137 1137 set_vm_result(NULL);
1138 1138 set_vm_result_2(NULL);
1139 1139 set_vframe_array_head(NULL);
1140 1140 set_vframe_array_last(NULL);
1141 1141 set_deferred_locals(NULL);
1142 1142 set_deopt_mark(NULL);
1143 1143 clear_must_deopt_id();
1144 1144 set_monitor_chunks(NULL);
1145 1145 set_next(NULL);
1146 1146 set_thread_state(_thread_new);
1147 1147 _terminated = _not_terminated;
1148 1148 _privileged_stack_top = NULL;
1149 1149 _array_for_gc = NULL;
1150 1150 _suspend_equivalent = false;
1151 1151 _in_deopt_handler = 0;
1152 1152 _doing_unsafe_access = false;
1153 1153 _stack_guard_state = stack_guard_unused;
1154 1154 _exception_oop = NULL;
1155 1155 _exception_pc = 0;
1156 1156 _exception_handler_pc = 0;
1157 1157 _exception_stack_size = 0;
1158 1158 _jvmti_thread_state= NULL;
1159 1159 _jvmti_get_loaded_classes_closure = NULL;
1160 1160 _interp_only_mode = 0;
1161 1161 _special_runtime_exit_condition = _no_async_condition;
1162 1162 _pending_async_exception = NULL;
1163 1163 _is_compiling = false;
1164 1164 _thread_stat = NULL;
1165 1165 _thread_stat = new ThreadStatistics();
1166 1166 _blocked_on_compilation = false;
1167 1167 _jni_active_critical = 0;
1168 1168 _do_not_unlock_if_synchronized = false;
1169 1169 _cached_monitor_info = NULL;
1170 1170 _parker = Parker::Allocate(this) ;
1171 1171
1172 1172 #ifndef PRODUCT
1173 1173 _jmp_ring_index = 0;
1174 1174 for (int ji = 0 ; ji < jump_ring_buffer_size ; ji++ ) {
1175 1175 record_jump(NULL, NULL, NULL, 0);
1176 1176 }
1177 1177 #endif /* PRODUCT */
1178 1178
1179 1179 set_thread_profiler(NULL);
1180 1180 if (FlatProfiler::is_active()) {
1181 1181 // This is where we would decide to either give each thread it's own profiler
1182 1182 // or use one global one from FlatProfiler,
1183 1183 // or up to some count of the number of profiled threads, etc.
1184 1184 ThreadProfiler* pp = new ThreadProfiler();
1185 1185 pp->engage();
1186 1186 set_thread_profiler(pp);
1187 1187 }
1188 1188
1189 1189 // Setup safepoint state info for this thread
1190 1190 ThreadSafepointState::create(this);
1191 1191
1192 1192 debug_only(_java_call_counter = 0);
1193 1193
1194 1194 // JVMTI PopFrame support
1195 1195 _popframe_condition = popframe_inactive;
1196 1196 _popframe_preserved_args = NULL;
1197 1197 _popframe_preserved_args_size = 0;
1198 1198
1199 1199 pd_initialize();
1200 1200 }
1201 1201
1202 1202 #ifndef SERIALGC
1203 1203 SATBMarkQueueSet JavaThread::_satb_mark_queue_set;
1204 1204 DirtyCardQueueSet JavaThread::_dirty_card_queue_set;
1205 1205 #endif // !SERIALGC
1206 1206
1207 1207 JavaThread::JavaThread(bool is_attaching) :
1208 1208 Thread()
1209 1209 #ifndef SERIALGC
1210 1210 , _satb_mark_queue(&_satb_mark_queue_set),
1211 1211 _dirty_card_queue(&_dirty_card_queue_set)
1212 1212 #endif // !SERIALGC
1213 1213 {
1214 1214 initialize();
1215 1215 _is_attaching = is_attaching;
1216 1216 assert(_deferred_card_mark.is_empty(), "Default MemRegion ctor");
1217 1217 }
1218 1218
1219 1219 bool JavaThread::reguard_stack(address cur_sp) {
1220 1220 if (_stack_guard_state != stack_guard_yellow_disabled) {
1221 1221 return true; // Stack already guarded or guard pages not needed.
1222 1222 }
1223 1223
1224 1224 if (register_stack_overflow()) {
1225 1225 // For those architectures which have separate register and
1226 1226 // memory stacks, we must check the register stack to see if
1227 1227 // it has overflowed.
1228 1228 return false;
1229 1229 }
1230 1230
1231 1231 // Java code never executes within the yellow zone: the latter is only
1232 1232 // there to provoke an exception during stack banging. If java code
1233 1233 // is executing there, either StackShadowPages should be larger, or
1234 1234 // some exception code in c1, c2 or the interpreter isn't unwinding
1235 1235 // when it should.
1236 1236 guarantee(cur_sp > stack_yellow_zone_base(), "not enough space to reguard - increase StackShadowPages");
1237 1237
1238 1238 enable_stack_yellow_zone();
1239 1239 return true;
1240 1240 }
1241 1241
1242 1242 bool JavaThread::reguard_stack(void) {
1243 1243 return reguard_stack(os::current_stack_pointer());
1244 1244 }
1245 1245
1246 1246
1247 1247 void JavaThread::block_if_vm_exited() {
1248 1248 if (_terminated == _vm_exited) {
1249 1249 // _vm_exited is set at safepoint, and Threads_lock is never released
1250 1250 // we will block here forever
1251 1251 Threads_lock->lock_without_safepoint_check();
1252 1252 ShouldNotReachHere();
1253 1253 }
1254 1254 }
1255 1255
1256 1256
1257 1257 // Remove this ifdef when C1 is ported to the compiler interface.
1258 1258 static void compiler_thread_entry(JavaThread* thread, TRAPS);
1259 1259
1260 1260 JavaThread::JavaThread(ThreadFunction entry_point, size_t stack_sz) :
1261 1261 Thread()
1262 1262 #ifndef SERIALGC
1263 1263 , _satb_mark_queue(&_satb_mark_queue_set),
1264 1264 _dirty_card_queue(&_dirty_card_queue_set)
1265 1265 #endif // !SERIALGC
1266 1266 {
1267 1267 if (TraceThreadEvents) {
1268 1268 tty->print_cr("creating thread %p", this);
1269 1269 }
1270 1270 initialize();
1271 1271 _is_attaching = false;
1272 1272 set_entry_point(entry_point);
1273 1273 // Create the native thread itself.
1274 1274 // %note runtime_23
1275 1275 os::ThreadType thr_type = os::java_thread;
1276 1276 thr_type = entry_point == &compiler_thread_entry ? os::compiler_thread :
1277 1277 os::java_thread;
1278 1278 os::create_thread(this, thr_type, stack_sz);
1279 1279
1280 1280 // The _osthread may be NULL here because we ran out of memory (too many threads active).
1281 1281 // We need to throw and OutOfMemoryError - however we cannot do this here because the caller
1282 1282 // may hold a lock and all locks must be unlocked before throwing the exception (throwing
1283 1283 // the exception consists of creating the exception object & initializing it, initialization
1284 1284 // will leave the VM via a JavaCall and then all locks must be unlocked).
1285 1285 //
1286 1286 // The thread is still suspended when we reach here. Thread must be explicit started
1287 1287 // by creator! Furthermore, the thread must also explicitly be added to the Threads list
1288 1288 // by calling Threads:add. The reason why this is not done here, is because the thread
1289 1289 // object must be fully initialized (take a look at JVM_Start)
1290 1290 }
1291 1291
1292 1292 JavaThread::~JavaThread() {
1293 1293 if (TraceThreadEvents) {
1294 1294 tty->print_cr("terminate thread %p", this);
1295 1295 }
1296 1296
1297 1297 // JSR166 -- return the parker to the free list
1298 1298 Parker::Release(_parker);
1299 1299 _parker = NULL ;
1300 1300
1301 1301 // Free any remaining previous UnrollBlock
1302 1302 vframeArray* old_array = vframe_array_last();
1303 1303
1304 1304 if (old_array != NULL) {
1305 1305 Deoptimization::UnrollBlock* old_info = old_array->unroll_block();
1306 1306 old_array->set_unroll_block(NULL);
1307 1307 delete old_info;
1308 1308 delete old_array;
1309 1309 }
1310 1310
1311 1311 GrowableArray<jvmtiDeferredLocalVariableSet*>* deferred = deferred_locals();
1312 1312 if (deferred != NULL) {
1313 1313 // This can only happen if thread is destroyed before deoptimization occurs.
1314 1314 assert(deferred->length() != 0, "empty array!");
1315 1315 do {
1316 1316 jvmtiDeferredLocalVariableSet* dlv = deferred->at(0);
1317 1317 deferred->remove_at(0);
1318 1318 // individual jvmtiDeferredLocalVariableSet are CHeapObj's
1319 1319 delete dlv;
1320 1320 } while (deferred->length() != 0);
1321 1321 delete deferred;
1322 1322 }
1323 1323
1324 1324 // All Java related clean up happens in exit
1325 1325 ThreadSafepointState::destroy(this);
1326 1326 if (_thread_profiler != NULL) delete _thread_profiler;
1327 1327 if (_thread_stat != NULL) delete _thread_stat;
1328 1328 }
1329 1329
1330 1330
1331 1331 // The first routine called by a new Java thread
1332 1332 void JavaThread::run() {
1333 1333 // initialize thread-local alloc buffer related fields
1334 1334 this->initialize_tlab();
1335 1335
1336 1336 // used to test validitity of stack trace backs
1337 1337 this->record_base_of_stack_pointer();
1338 1338
1339 1339 // Record real stack base and size.
1340 1340 this->record_stack_base_and_size();
1341 1341
1342 1342 // Initialize thread local storage; set before calling MutexLocker
1343 1343 this->initialize_thread_local_storage();
1344 1344
1345 1345 this->create_stack_guard_pages();
1346 1346
1347 1347 // Thread is now sufficient initialized to be handled by the safepoint code as being
1348 1348 // in the VM. Change thread state from _thread_new to _thread_in_vm
1349 1349 ThreadStateTransition::transition_and_fence(this, _thread_new, _thread_in_vm);
1350 1350
1351 1351 assert(JavaThread::current() == this, "sanity check");
1352 1352 assert(!Thread::current()->owns_locks(), "sanity check");
1353 1353
1354 1354 DTRACE_THREAD_PROBE(start, this);
1355 1355
1356 1356 // This operation might block. We call that after all safepoint checks for a new thread has
1357 1357 // been completed.
1358 1358 this->set_active_handles(JNIHandleBlock::allocate_block());
1359 1359
1360 1360 if (JvmtiExport::should_post_thread_life()) {
1361 1361 JvmtiExport::post_thread_start(this);
1362 1362 }
1363 1363
1364 1364 // We call another function to do the rest so we are sure that the stack addresses used
1365 1365 // from there will be lower than the stack base just computed
1366 1366 thread_main_inner();
1367 1367
1368 1368 // Note, thread is no longer valid at this point!
1369 1369 }
1370 1370
1371 1371
1372 1372 void JavaThread::thread_main_inner() {
1373 1373 assert(JavaThread::current() == this, "sanity check");
1374 1374 assert(this->threadObj() != NULL, "just checking");
1375 1375
1376 1376 // Execute thread entry point. If this thread is being asked to restart,
1377 1377 // or has been stopped before starting, do not reexecute entry point.
1378 1378 // Note: Due to JVM_StopThread we can have pending exceptions already!
1379 1379 if (!this->has_pending_exception() && !java_lang_Thread::is_stillborn(this->threadObj())) {
1380 1380 // enter the thread's entry point only if we have no pending exceptions
1381 1381 HandleMark hm(this);
1382 1382 this->entry_point()(this, this);
1383 1383 }
1384 1384
1385 1385 DTRACE_THREAD_PROBE(stop, this);
1386 1386
1387 1387 this->exit(false);
1388 1388 delete this;
1389 1389 }
1390 1390
1391 1391
1392 1392 static void ensure_join(JavaThread* thread) {
1393 1393 // We do not need to grap the Threads_lock, since we are operating on ourself.
1394 1394 Handle threadObj(thread, thread->threadObj());
1395 1395 assert(threadObj.not_null(), "java thread object must exist");
1396 1396 ObjectLocker lock(threadObj, thread);
1397 1397 // Ignore pending exception (ThreadDeath), since we are exiting anyway
1398 1398 thread->clear_pending_exception();
1399 1399 // It is of profound importance that we set the stillborn bit and reset the thread object,
1400 1400 // before we do the notify. Since, changing these two variable will make JVM_IsAlive return
1401 1401 // false. So in case another thread is doing a join on this thread , it will detect that the thread
1402 1402 // is dead when it gets notified.
1403 1403 java_lang_Thread::set_stillborn(threadObj());
1404 1404 // Thread is exiting. So set thread_status field in java.lang.Thread class to TERMINATED.
1405 1405 java_lang_Thread::set_thread_status(threadObj(), java_lang_Thread::TERMINATED);
1406 1406 java_lang_Thread::set_thread(threadObj(), NULL);
1407 1407 lock.notify_all(thread);
1408 1408 // Ignore pending exception (ThreadDeath), since we are exiting anyway
1409 1409 thread->clear_pending_exception();
1410 1410 }
1411 1411
1412 1412
1413 1413 // For any new cleanup additions, please check to see if they need to be applied to
1414 1414 // cleanup_failed_attach_current_thread as well.
1415 1415 void JavaThread::exit(bool destroy_vm, ExitType exit_type) {
1416 1416 assert(this == JavaThread::current(), "thread consistency check");
1417 1417 if (!InitializeJavaLangSystem) return;
1418 1418
1419 1419 HandleMark hm(this);
1420 1420 Handle uncaught_exception(this, this->pending_exception());
1421 1421 this->clear_pending_exception();
1422 1422 Handle threadObj(this, this->threadObj());
1423 1423 assert(threadObj.not_null(), "Java thread object should be created");
1424 1424
1425 1425 if (get_thread_profiler() != NULL) {
1426 1426 get_thread_profiler()->disengage();
1427 1427 ResourceMark rm;
1428 1428 get_thread_profiler()->print(get_thread_name());
1429 1429 }
1430 1430
1431 1431
1432 1432 // FIXIT: This code should be moved into else part, when reliable 1.2/1.3 check is in place
1433 1433 {
1434 1434 EXCEPTION_MARK;
1435 1435
1436 1436 CLEAR_PENDING_EXCEPTION;
1437 1437 }
1438 1438 // FIXIT: The is_null check is only so it works better on JDK1.2 VM's. This
1439 1439 // has to be fixed by a runtime query method
1440 1440 if (!destroy_vm || JDK_Version::is_jdk12x_version()) {
1441 1441 // JSR-166: change call from from ThreadGroup.uncaughtException to
1442 1442 // java.lang.Thread.dispatchUncaughtException
1443 1443 if (uncaught_exception.not_null()) {
1444 1444 Handle group(this, java_lang_Thread::threadGroup(threadObj()));
1445 1445 Events::log("uncaught exception INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT",
1446 1446 (address)uncaught_exception(), (address)threadObj(), (address)group());
1447 1447 {
1448 1448 EXCEPTION_MARK;
1449 1449 // Check if the method Thread.dispatchUncaughtException() exists. If so
1450 1450 // call it. Otherwise we have an older library without the JSR-166 changes,
1451 1451 // so call ThreadGroup.uncaughtException()
1452 1452 KlassHandle recvrKlass(THREAD, threadObj->klass());
1453 1453 CallInfo callinfo;
1454 1454 KlassHandle thread_klass(THREAD, SystemDictionary::thread_klass());
1455 1455 LinkResolver::resolve_virtual_call(callinfo, threadObj, recvrKlass, thread_klass,
1456 1456 vmSymbolHandles::dispatchUncaughtException_name(),
1457 1457 vmSymbolHandles::throwable_void_signature(),
1458 1458 KlassHandle(), false, false, THREAD);
1459 1459 CLEAR_PENDING_EXCEPTION;
1460 1460 methodHandle method = callinfo.selected_method();
1461 1461 if (method.not_null()) {
1462 1462 JavaValue result(T_VOID);
1463 1463 JavaCalls::call_virtual(&result,
1464 1464 threadObj, thread_klass,
1465 1465 vmSymbolHandles::dispatchUncaughtException_name(),
1466 1466 vmSymbolHandles::throwable_void_signature(),
1467 1467 uncaught_exception,
1468 1468 THREAD);
1469 1469 } else {
1470 1470 KlassHandle thread_group(THREAD, SystemDictionary::threadGroup_klass());
1471 1471 JavaValue result(T_VOID);
1472 1472 JavaCalls::call_virtual(&result,
1473 1473 group, thread_group,
1474 1474 vmSymbolHandles::uncaughtException_name(),
1475 1475 vmSymbolHandles::thread_throwable_void_signature(),
1476 1476 threadObj, // Arg 1
1477 1477 uncaught_exception, // Arg 2
1478 1478 THREAD);
1479 1479 }
1480 1480 CLEAR_PENDING_EXCEPTION;
1481 1481 }
1482 1482 }
1483 1483
1484 1484 // Call Thread.exit(). We try 3 times in case we got another Thread.stop during
1485 1485 // the execution of the method. If that is not enough, then we don't really care. Thread.stop
1486 1486 // is deprecated anyhow.
1487 1487 { int count = 3;
1488 1488 while (java_lang_Thread::threadGroup(threadObj()) != NULL && (count-- > 0)) {
1489 1489 EXCEPTION_MARK;
1490 1490 JavaValue result(T_VOID);
1491 1491 KlassHandle thread_klass(THREAD, SystemDictionary::thread_klass());
1492 1492 JavaCalls::call_virtual(&result,
1493 1493 threadObj, thread_klass,
1494 1494 vmSymbolHandles::exit_method_name(),
1495 1495 vmSymbolHandles::void_method_signature(),
1496 1496 THREAD);
1497 1497 CLEAR_PENDING_EXCEPTION;
1498 1498 }
1499 1499 }
1500 1500
1501 1501 // notify JVMTI
1502 1502 if (JvmtiExport::should_post_thread_life()) {
1503 1503 JvmtiExport::post_thread_end(this);
1504 1504 }
1505 1505
1506 1506 // We have notified the agents that we are exiting, before we go on,
1507 1507 // we must check for a pending external suspend request and honor it
1508 1508 // in order to not surprise the thread that made the suspend request.
1509 1509 while (true) {
1510 1510 {
1511 1511 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1512 1512 if (!is_external_suspend()) {
1513 1513 set_terminated(_thread_exiting);
1514 1514 ThreadService::current_thread_exiting(this);
1515 1515 break;
1516 1516 }
1517 1517 // Implied else:
1518 1518 // Things get a little tricky here. We have a pending external
1519 1519 // suspend request, but we are holding the SR_lock so we
1520 1520 // can't just self-suspend. So we temporarily drop the lock
1521 1521 // and then self-suspend.
1522 1522 }
1523 1523
1524 1524 ThreadBlockInVM tbivm(this);
1525 1525 java_suspend_self();
1526 1526
1527 1527 // We're done with this suspend request, but we have to loop around
1528 1528 // and check again. Eventually we will get SR_lock without a pending
1529 1529 // external suspend request and will be able to mark ourselves as
1530 1530 // exiting.
1531 1531 }
1532 1532 // no more external suspends are allowed at this point
1533 1533 } else {
1534 1534 // before_exit() has already posted JVMTI THREAD_END events
1535 1535 }
1536 1536
1537 1537 // Notify waiters on thread object. This has to be done after exit() is called
1538 1538 // on the thread (if the thread is the last thread in a daemon ThreadGroup the
1539 1539 // group should have the destroyed bit set before waiters are notified).
1540 1540 ensure_join(this);
1541 1541 assert(!this->has_pending_exception(), "ensure_join should have cleared");
1542 1542
1543 1543 // 6282335 JNI DetachCurrentThread spec states that all Java monitors
1544 1544 // held by this thread must be released. A detach operation must only
1545 1545 // get here if there are no Java frames on the stack. Therefore, any
1546 1546 // owned monitors at this point MUST be JNI-acquired monitors which are
1547 1547 // pre-inflated and in the monitor cache.
1548 1548 //
1549 1549 // ensure_join() ignores IllegalThreadStateExceptions, and so does this.
1550 1550 if (exit_type == jni_detach && JNIDetachReleasesMonitors) {
1551 1551 assert(!this->has_last_Java_frame(), "detaching with Java frames?");
1552 1552 ObjectSynchronizer::release_monitors_owned_by_thread(this);
1553 1553 assert(!this->has_pending_exception(), "release_monitors should have cleared");
1554 1554 }
1555 1555
1556 1556 // These things needs to be done while we are still a Java Thread. Make sure that thread
1557 1557 // is in a consistent state, in case GC happens
1558 1558 assert(_privileged_stack_top == NULL, "must be NULL when we get here");
1559 1559
1560 1560 if (active_handles() != NULL) {
1561 1561 JNIHandleBlock* block = active_handles();
1562 1562 set_active_handles(NULL);
1563 1563 JNIHandleBlock::release_block(block);
1564 1564 }
1565 1565
1566 1566 if (free_handle_block() != NULL) {
1567 1567 JNIHandleBlock* block = free_handle_block();
1568 1568 set_free_handle_block(NULL);
1569 1569 JNIHandleBlock::release_block(block);
1570 1570 }
1571 1571
1572 1572 // These have to be removed while this is still a valid thread.
1573 1573 remove_stack_guard_pages();
1574 1574
1575 1575 if (UseTLAB) {
1576 1576 tlab().make_parsable(true); // retire TLAB
1577 1577 }
1578 1578
1579 1579 if (jvmti_thread_state() != NULL) {
1580 1580 JvmtiExport::cleanup_thread(this);
1581 1581 }
1582 1582
1583 1583 #ifndef SERIALGC
1584 1584 // We must flush G1-related buffers before removing a thread from
1585 1585 // the list of active threads.
1586 1586 if (UseG1GC) {
1587 1587 flush_barrier_queues();
1588 1588 }
1589 1589 #endif
1590 1590
1591 1591 // Remove from list of active threads list, and notify VM thread if we are the last non-daemon thread
1592 1592 Threads::remove(this);
1593 1593 }
1594 1594
1595 1595 #ifndef SERIALGC
1596 1596 // Flush G1-related queues.
1597 1597 void JavaThread::flush_barrier_queues() {
1598 1598 satb_mark_queue().flush();
1599 1599 dirty_card_queue().flush();
1600 1600 }
1601 1601 #endif
1602 1602
1603 1603 void JavaThread::cleanup_failed_attach_current_thread() {
1604 1604 if (get_thread_profiler() != NULL) {
1605 1605 get_thread_profiler()->disengage();
1606 1606 ResourceMark rm;
1607 1607 get_thread_profiler()->print(get_thread_name());
1608 1608 }
1609 1609
1610 1610 if (active_handles() != NULL) {
1611 1611 JNIHandleBlock* block = active_handles();
1612 1612 set_active_handles(NULL);
1613 1613 JNIHandleBlock::release_block(block);
1614 1614 }
1615 1615
1616 1616 if (free_handle_block() != NULL) {
1617 1617 JNIHandleBlock* block = free_handle_block();
1618 1618 set_free_handle_block(NULL);
1619 1619 JNIHandleBlock::release_block(block);
1620 1620 }
1621 1621
1622 1622 if (UseTLAB) {
1623 1623 tlab().make_parsable(true); // retire TLAB, if any
1624 1624 }
1625 1625
1626 1626 #ifndef SERIALGC
1627 1627 if (UseG1GC) {
1628 1628 flush_barrier_queues();
1629 1629 }
1630 1630 #endif
1631 1631
1632 1632 Threads::remove(this);
1633 1633 delete this;
1634 1634 }
1635 1635
1636 1636
1637 1637
1638 1638
1639 1639 JavaThread* JavaThread::active() {
1640 1640 Thread* thread = ThreadLocalStorage::thread();
1641 1641 assert(thread != NULL, "just checking");
1642 1642 if (thread->is_Java_thread()) {
1643 1643 return (JavaThread*) thread;
1644 1644 } else {
1645 1645 assert(thread->is_VM_thread(), "this must be a vm thread");
1646 1646 VM_Operation* op = ((VMThread*) thread)->vm_operation();
1647 1647 JavaThread *ret=op == NULL ? NULL : (JavaThread *)op->calling_thread();
1648 1648 assert(ret->is_Java_thread(), "must be a Java thread");
1649 1649 return ret;
1650 1650 }
1651 1651 }
1652 1652
1653 1653 bool JavaThread::is_lock_owned(address adr) const {
1654 1654 if (Thread::is_lock_owned(adr)) return true;
1655 1655
1656 1656 for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) {
1657 1657 if (chunk->contains(adr)) return true;
1658 1658 }
1659 1659
1660 1660 return false;
1661 1661 }
1662 1662
1663 1663
1664 1664 void JavaThread::add_monitor_chunk(MonitorChunk* chunk) {
1665 1665 chunk->set_next(monitor_chunks());
1666 1666 set_monitor_chunks(chunk);
1667 1667 }
1668 1668
1669 1669 void JavaThread::remove_monitor_chunk(MonitorChunk* chunk) {
1670 1670 guarantee(monitor_chunks() != NULL, "must be non empty");
1671 1671 if (monitor_chunks() == chunk) {
1672 1672 set_monitor_chunks(chunk->next());
1673 1673 } else {
1674 1674 MonitorChunk* prev = monitor_chunks();
1675 1675 while (prev->next() != chunk) prev = prev->next();
1676 1676 prev->set_next(chunk->next());
1677 1677 }
1678 1678 }
1679 1679
1680 1680 // JVM support.
1681 1681
1682 1682 // Note: this function shouldn't block if it's called in
1683 1683 // _thread_in_native_trans state (such as from
1684 1684 // check_special_condition_for_native_trans()).
1685 1685 void JavaThread::check_and_handle_async_exceptions(bool check_unsafe_error) {
1686 1686
1687 1687 if (has_last_Java_frame() && has_async_condition()) {
1688 1688 // If we are at a polling page safepoint (not a poll return)
1689 1689 // then we must defer async exception because live registers
1690 1690 // will be clobbered by the exception path. Poll return is
1691 1691 // ok because the call we a returning from already collides
1692 1692 // with exception handling registers and so there is no issue.
1693 1693 // (The exception handling path kills call result registers but
1694 1694 // this is ok since the exception kills the result anyway).
1695 1695
1696 1696 if (is_at_poll_safepoint()) {
1697 1697 // if the code we are returning to has deoptimized we must defer
1698 1698 // the exception otherwise live registers get clobbered on the
1699 1699 // exception path before deoptimization is able to retrieve them.
1700 1700 //
1701 1701 RegisterMap map(this, false);
1702 1702 frame caller_fr = last_frame().sender(&map);
1703 1703 assert(caller_fr.is_compiled_frame(), "what?");
1704 1704 if (caller_fr.is_deoptimized_frame()) {
1705 1705 if (TraceExceptions) {
1706 1706 ResourceMark rm;
1707 1707 tty->print_cr("deferred async exception at compiled safepoint");
1708 1708 }
1709 1709 return;
1710 1710 }
1711 1711 }
1712 1712 }
1713 1713
1714 1714 JavaThread::AsyncRequests condition = clear_special_runtime_exit_condition();
1715 1715 if (condition == _no_async_condition) {
1716 1716 // Conditions have changed since has_special_runtime_exit_condition()
1717 1717 // was called:
1718 1718 // - if we were here only because of an external suspend request,
1719 1719 // then that was taken care of above (or cancelled) so we are done
1720 1720 // - if we were here because of another async request, then it has
1721 1721 // been cleared between the has_special_runtime_exit_condition()
1722 1722 // and now so again we are done
1723 1723 return;
1724 1724 }
1725 1725
1726 1726 // Check for pending async. exception
1727 1727 if (_pending_async_exception != NULL) {
1728 1728 // Only overwrite an already pending exception, if it is not a threadDeath.
1729 1729 if (!has_pending_exception() || !pending_exception()->is_a(SystemDictionary::threaddeath_klass())) {
1730 1730
1731 1731 // We cannot call Exceptions::_throw(...) here because we cannot block
1732 1732 set_pending_exception(_pending_async_exception, __FILE__, __LINE__);
1733 1733
1734 1734 if (TraceExceptions) {
1735 1735 ResourceMark rm;
1736 1736 tty->print("Async. exception installed at runtime exit (" INTPTR_FORMAT ")", this);
1737 1737 if (has_last_Java_frame() ) {
1738 1738 frame f = last_frame();
1739 1739 tty->print(" (pc: " INTPTR_FORMAT " sp: " INTPTR_FORMAT " )", f.pc(), f.sp());
1740 1740 }
1741 1741 tty->print_cr(" of type: %s", instanceKlass::cast(_pending_async_exception->klass())->external_name());
1742 1742 }
1743 1743 _pending_async_exception = NULL;
1744 1744 clear_has_async_exception();
1745 1745 }
1746 1746 }
1747 1747
1748 1748 if (check_unsafe_error &&
1749 1749 condition == _async_unsafe_access_error && !has_pending_exception()) {
1750 1750 condition = _no_async_condition; // done
1751 1751 switch (thread_state()) {
1752 1752 case _thread_in_vm:
1753 1753 {
1754 1754 JavaThread* THREAD = this;
1755 1755 THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in an unsafe memory access operation");
1756 1756 }
1757 1757 case _thread_in_native:
1758 1758 {
1759 1759 ThreadInVMfromNative tiv(this);
1760 1760 JavaThread* THREAD = this;
1761 1761 THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in an unsafe memory access operation");
1762 1762 }
1763 1763 case _thread_in_Java:
1764 1764 {
1765 1765 ThreadInVMfromJava tiv(this);
1766 1766 JavaThread* THREAD = this;
1767 1767 THROW_MSG(vmSymbols::java_lang_InternalError(), "a fault occurred in a recent unsafe memory access operation in compiled Java code");
1768 1768 }
1769 1769 default:
1770 1770 ShouldNotReachHere();
1771 1771 }
1772 1772 }
1773 1773
1774 1774 assert(condition == _no_async_condition || has_pending_exception() ||
1775 1775 (!check_unsafe_error && condition == _async_unsafe_access_error),
1776 1776 "must have handled the async condition, if no exception");
1777 1777 }
1778 1778
1779 1779 void JavaThread::handle_special_runtime_exit_condition(bool check_asyncs) {
1780 1780 //
1781 1781 // Check for pending external suspend. Internal suspend requests do
1782 1782 // not use handle_special_runtime_exit_condition().
1783 1783 // If JNIEnv proxies are allowed, don't self-suspend if the target
1784 1784 // thread is not the current thread. In older versions of jdbx, jdbx
1785 1785 // threads could call into the VM with another thread's JNIEnv so we
1786 1786 // can be here operating on behalf of a suspended thread (4432884).
1787 1787 bool do_self_suspend = is_external_suspend_with_lock();
1788 1788 if (do_self_suspend && (!AllowJNIEnvProxy || this == JavaThread::current())) {
1789 1789 //
1790 1790 // Because thread is external suspended the safepoint code will count
1791 1791 // thread as at a safepoint. This can be odd because we can be here
1792 1792 // as _thread_in_Java which would normally transition to _thread_blocked
1793 1793 // at a safepoint. We would like to mark the thread as _thread_blocked
1794 1794 // before calling java_suspend_self like all other callers of it but
1795 1795 // we must then observe proper safepoint protocol. (We can't leave
1796 1796 // _thread_blocked with a safepoint in progress). However we can be
1797 1797 // here as _thread_in_native_trans so we can't use a normal transition
1798 1798 // constructor/destructor pair because they assert on that type of
1799 1799 // transition. We could do something like:
1800 1800 //
1801 1801 // JavaThreadState state = thread_state();
1802 1802 // set_thread_state(_thread_in_vm);
1803 1803 // {
1804 1804 // ThreadBlockInVM tbivm(this);
1805 1805 // java_suspend_self()
1806 1806 // }
1807 1807 // set_thread_state(_thread_in_vm_trans);
1808 1808 // if (safepoint) block;
1809 1809 // set_thread_state(state);
1810 1810 //
1811 1811 // but that is pretty messy. Instead we just go with the way the
1812 1812 // code has worked before and note that this is the only path to
1813 1813 // java_suspend_self that doesn't put the thread in _thread_blocked
1814 1814 // mode.
1815 1815
1816 1816 frame_anchor()->make_walkable(this);
1817 1817 java_suspend_self();
1818 1818
1819 1819 // We might be here for reasons in addition to the self-suspend request
1820 1820 // so check for other async requests.
1821 1821 }
1822 1822
1823 1823 if (check_asyncs) {
1824 1824 check_and_handle_async_exceptions();
1825 1825 }
1826 1826 }
1827 1827
1828 1828 void JavaThread::send_thread_stop(oop java_throwable) {
1829 1829 assert(Thread::current()->is_VM_thread(), "should be in the vm thread");
1830 1830 assert(Threads_lock->is_locked(), "Threads_lock should be locked by safepoint code");
1831 1831 assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
1832 1832
1833 1833 // Do not throw asynchronous exceptions against the compiler thread
1834 1834 // (the compiler thread should not be a Java thread -- fix in 1.4.2)
1835 1835 if (is_Compiler_thread()) return;
1836 1836
1837 1837 // This is a change from JDK 1.1, but JDK 1.2 will also do it:
1838 1838 if (java_throwable->is_a(SystemDictionary::threaddeath_klass())) {
1839 1839 java_lang_Thread::set_stillborn(threadObj());
1840 1840 }
1841 1841
1842 1842 {
1843 1843 // Actually throw the Throwable against the target Thread - however
1844 1844 // only if there is no thread death exception installed already.
1845 1845 if (_pending_async_exception == NULL || !_pending_async_exception->is_a(SystemDictionary::threaddeath_klass())) {
1846 1846 // If the topmost frame is a runtime stub, then we are calling into
1847 1847 // OptoRuntime from compiled code. Some runtime stubs (new, monitor_exit..)
1848 1848 // must deoptimize the caller before continuing, as the compiled exception handler table
1849 1849 // may not be valid
1850 1850 if (has_last_Java_frame()) {
1851 1851 frame f = last_frame();
1852 1852 if (f.is_runtime_frame() || f.is_safepoint_blob_frame()) {
1853 1853 // BiasedLocking needs an updated RegisterMap for the revoke monitors pass
1854 1854 RegisterMap reg_map(this, UseBiasedLocking);
1855 1855 frame compiled_frame = f.sender(®_map);
1856 1856 if (compiled_frame.can_be_deoptimized()) {
1857 1857 Deoptimization::deoptimize(this, compiled_frame, ®_map);
1858 1858 }
1859 1859 }
1860 1860 }
1861 1861
1862 1862 // Set async. pending exception in thread.
1863 1863 set_pending_async_exception(java_throwable);
1864 1864
1865 1865 if (TraceExceptions) {
1866 1866 ResourceMark rm;
1867 1867 tty->print_cr("Pending Async. exception installed of type: %s", instanceKlass::cast(_pending_async_exception->klass())->external_name());
1868 1868 }
1869 1869 // for AbortVMOnException flag
1870 1870 NOT_PRODUCT(Exceptions::debug_check_abort(instanceKlass::cast(_pending_async_exception->klass())->external_name()));
1871 1871 }
1872 1872 }
1873 1873
1874 1874
1875 1875 // Interrupt thread so it will wake up from a potential wait()
1876 1876 Thread::interrupt(this);
1877 1877 }
1878 1878
1879 1879 // External suspension mechanism.
1880 1880 //
1881 1881 // Tell the VM to suspend a thread when ever it knows that it does not hold on
1882 1882 // to any VM_locks and it is at a transition
1883 1883 // Self-suspension will happen on the transition out of the vm.
1884 1884 // Catch "this" coming in from JNIEnv pointers when the thread has been freed
1885 1885 //
1886 1886 // Guarantees on return:
1887 1887 // + Target thread will not execute any new bytecode (that's why we need to
1888 1888 // force a safepoint)
1889 1889 // + Target thread will not enter any new monitors
1890 1890 //
1891 1891 void JavaThread::java_suspend() {
1892 1892 { MutexLocker mu(Threads_lock);
1893 1893 if (!Threads::includes(this) || is_exiting() || this->threadObj() == NULL) {
1894 1894 return;
1895 1895 }
1896 1896 }
1897 1897
1898 1898 { MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1899 1899 if (!is_external_suspend()) {
1900 1900 // a racing resume has cancelled us; bail out now
1901 1901 return;
1902 1902 }
1903 1903
1904 1904 // suspend is done
1905 1905 uint32_t debug_bits = 0;
1906 1906 // Warning: is_ext_suspend_completed() may temporarily drop the
1907 1907 // SR_lock to allow the thread to reach a stable thread state if
1908 1908 // it is currently in a transient thread state.
1909 1909 if (is_ext_suspend_completed(false /* !called_by_wait */,
1910 1910 SuspendRetryDelay, &debug_bits) ) {
1911 1911 return;
1912 1912 }
1913 1913 }
1914 1914
1915 1915 VM_ForceSafepoint vm_suspend;
1916 1916 VMThread::execute(&vm_suspend);
1917 1917 }
1918 1918
1919 1919 // Part II of external suspension.
1920 1920 // A JavaThread self suspends when it detects a pending external suspend
1921 1921 // request. This is usually on transitions. It is also done in places
1922 1922 // where continuing to the next transition would surprise the caller,
1923 1923 // e.g., monitor entry.
1924 1924 //
1925 1925 // Returns the number of times that the thread self-suspended.
1926 1926 //
1927 1927 // Note: DO NOT call java_suspend_self() when you just want to block current
1928 1928 // thread. java_suspend_self() is the second stage of cooperative
1929 1929 // suspension for external suspend requests and should only be used
1930 1930 // to complete an external suspend request.
1931 1931 //
1932 1932 int JavaThread::java_suspend_self() {
1933 1933 int ret = 0;
1934 1934
1935 1935 // we are in the process of exiting so don't suspend
1936 1936 if (is_exiting()) {
1937 1937 clear_external_suspend();
1938 1938 return ret;
1939 1939 }
1940 1940
1941 1941 assert(_anchor.walkable() ||
1942 1942 (is_Java_thread() && !((JavaThread*)this)->has_last_Java_frame()),
1943 1943 "must have walkable stack");
1944 1944
1945 1945 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
1946 1946
1947 1947 assert(!this->is_ext_suspended(),
1948 1948 "a thread trying to self-suspend should not already be suspended");
1949 1949
1950 1950 if (this->is_suspend_equivalent()) {
1951 1951 // If we are self-suspending as a result of the lifting of a
1952 1952 // suspend equivalent condition, then the suspend_equivalent
1953 1953 // flag is not cleared until we set the ext_suspended flag so
1954 1954 // that wait_for_ext_suspend_completion() returns consistent
1955 1955 // results.
1956 1956 this->clear_suspend_equivalent();
1957 1957 }
1958 1958
1959 1959 // A racing resume may have cancelled us before we grabbed SR_lock
1960 1960 // above. Or another external suspend request could be waiting for us
1961 1961 // by the time we return from SR_lock()->wait(). The thread
1962 1962 // that requested the suspension may already be trying to walk our
1963 1963 // stack and if we return now, we can change the stack out from under
1964 1964 // it. This would be a "bad thing (TM)" and cause the stack walker
1965 1965 // to crash. We stay self-suspended until there are no more pending
1966 1966 // external suspend requests.
1967 1967 while (is_external_suspend()) {
1968 1968 ret++;
1969 1969 this->set_ext_suspended();
1970 1970
1971 1971 // _ext_suspended flag is cleared by java_resume()
1972 1972 while (is_ext_suspended()) {
1973 1973 this->SR_lock()->wait(Mutex::_no_safepoint_check_flag);
1974 1974 }
1975 1975 }
1976 1976
1977 1977 return ret;
1978 1978 }
1979 1979
1980 1980 #ifdef ASSERT
1981 1981 // verify the JavaThread has not yet been published in the Threads::list, and
1982 1982 // hence doesn't need protection from concurrent access at this stage
1983 1983 void JavaThread::verify_not_published() {
1984 1984 if (!Threads_lock->owned_by_self()) {
1985 1985 MutexLockerEx ml(Threads_lock, Mutex::_no_safepoint_check_flag);
1986 1986 assert( !Threads::includes(this),
1987 1987 "java thread shouldn't have been published yet!");
1988 1988 }
1989 1989 else {
1990 1990 assert( !Threads::includes(this),
1991 1991 "java thread shouldn't have been published yet!");
1992 1992 }
1993 1993 }
1994 1994 #endif
1995 1995
1996 1996 // Slow path when the native==>VM/Java barriers detect a safepoint is in
1997 1997 // progress or when _suspend_flags is non-zero.
1998 1998 // Current thread needs to self-suspend if there is a suspend request and/or
1999 1999 // block if a safepoint is in progress.
2000 2000 // Async exception ISN'T checked.
2001 2001 // Note only the ThreadInVMfromNative transition can call this function
2002 2002 // directly and when thread state is _thread_in_native_trans
2003 2003 void JavaThread::check_safepoint_and_suspend_for_native_trans(JavaThread *thread) {
2004 2004 assert(thread->thread_state() == _thread_in_native_trans, "wrong state");
2005 2005
2006 2006 JavaThread *curJT = JavaThread::current();
2007 2007 bool do_self_suspend = thread->is_external_suspend();
2008 2008
2009 2009 assert(!curJT->has_last_Java_frame() || curJT->frame_anchor()->walkable(), "Unwalkable stack in native->vm transition");
2010 2010
2011 2011 // If JNIEnv proxies are allowed, don't self-suspend if the target
2012 2012 // thread is not the current thread. In older versions of jdbx, jdbx
2013 2013 // threads could call into the VM with another thread's JNIEnv so we
2014 2014 // can be here operating on behalf of a suspended thread (4432884).
2015 2015 if (do_self_suspend && (!AllowJNIEnvProxy || curJT == thread)) {
2016 2016 JavaThreadState state = thread->thread_state();
2017 2017
2018 2018 // We mark this thread_blocked state as a suspend-equivalent so
2019 2019 // that a caller to is_ext_suspend_completed() won't be confused.
2020 2020 // The suspend-equivalent state is cleared by java_suspend_self().
2021 2021 thread->set_suspend_equivalent();
2022 2022
2023 2023 // If the safepoint code sees the _thread_in_native_trans state, it will
2024 2024 // wait until the thread changes to other thread state. There is no
2025 2025 // guarantee on how soon we can obtain the SR_lock and complete the
2026 2026 // self-suspend request. It would be a bad idea to let safepoint wait for
2027 2027 // too long. Temporarily change the state to _thread_blocked to
2028 2028 // let the VM thread know that this thread is ready for GC. The problem
2029 2029 // of changing thread state is that safepoint could happen just after
2030 2030 // java_suspend_self() returns after being resumed, and VM thread will
2031 2031 // see the _thread_blocked state. We must check for safepoint
2032 2032 // after restoring the state and make sure we won't leave while a safepoint
2033 2033 // is in progress.
2034 2034 thread->set_thread_state(_thread_blocked);
2035 2035 thread->java_suspend_self();
2036 2036 thread->set_thread_state(state);
2037 2037 // Make sure new state is seen by VM thread
2038 2038 if (os::is_MP()) {
2039 2039 if (UseMembar) {
2040 2040 // Force a fence between the write above and read below
2041 2041 OrderAccess::fence();
2042 2042 } else {
2043 2043 // Must use this rather than serialization page in particular on Windows
2044 2044 InterfaceSupport::serialize_memory(thread);
2045 2045 }
2046 2046 }
2047 2047 }
2048 2048
2049 2049 if (SafepointSynchronize::do_call_back()) {
2050 2050 // If we are safepointing, then block the caller which may not be
2051 2051 // the same as the target thread (see above).
2052 2052 SafepointSynchronize::block(curJT);
2053 2053 }
2054 2054
2055 2055 if (thread->is_deopt_suspend()) {
2056 2056 thread->clear_deopt_suspend();
2057 2057 RegisterMap map(thread, false);
2058 2058 frame f = thread->last_frame();
2059 2059 while ( f.id() != thread->must_deopt_id() && ! f.is_first_frame()) {
2060 2060 f = f.sender(&map);
2061 2061 }
2062 2062 if (f.id() == thread->must_deopt_id()) {
2063 2063 thread->clear_must_deopt_id();
2064 2064 // Since we know we're safe to deopt the current state is a safe state
2065 2065 f.deoptimize(thread, true);
2066 2066 } else {
2067 2067 fatal("missed deoptimization!");
2068 2068 }
2069 2069 }
2070 2070 }
2071 2071
2072 2072 // Slow path when the native==>VM/Java barriers detect a safepoint is in
2073 2073 // progress or when _suspend_flags is non-zero.
2074 2074 // Current thread needs to self-suspend if there is a suspend request and/or
2075 2075 // block if a safepoint is in progress.
2076 2076 // Also check for pending async exception (not including unsafe access error).
2077 2077 // Note only the native==>VM/Java barriers can call this function and when
2078 2078 // thread state is _thread_in_native_trans.
2079 2079 void JavaThread::check_special_condition_for_native_trans(JavaThread *thread) {
2080 2080 check_safepoint_and_suspend_for_native_trans(thread);
2081 2081
2082 2082 if (thread->has_async_exception()) {
2083 2083 // We are in _thread_in_native_trans state, don't handle unsafe
2084 2084 // access error since that may block.
2085 2085 thread->check_and_handle_async_exceptions(false);
2086 2086 }
2087 2087 }
2088 2088
2089 2089 // We need to guarantee the Threads_lock here, since resumes are not
2090 2090 // allowed during safepoint synchronization
2091 2091 // Can only resume from an external suspension
2092 2092 void JavaThread::java_resume() {
2093 2093 assert_locked_or_safepoint(Threads_lock);
2094 2094
2095 2095 // Sanity check: thread is gone, has started exiting or the thread
2096 2096 // was not externally suspended.
2097 2097 if (!Threads::includes(this) || is_exiting() || !is_external_suspend()) {
2098 2098 return;
2099 2099 }
2100 2100
2101 2101 MutexLockerEx ml(SR_lock(), Mutex::_no_safepoint_check_flag);
2102 2102
2103 2103 clear_external_suspend();
2104 2104
2105 2105 if (is_ext_suspended()) {
2106 2106 clear_ext_suspended();
2107 2107 SR_lock()->notify_all();
2108 2108 }
2109 2109 }
2110 2110
2111 2111 void JavaThread::create_stack_guard_pages() {
2112 2112 if (! os::uses_stack_guard_pages() || _stack_guard_state != stack_guard_unused) return;
2113 2113 address low_addr = stack_base() - stack_size();
2114 2114 size_t len = (StackYellowPages + StackRedPages) * os::vm_page_size();
2115 2115
2116 2116 int allocate = os::allocate_stack_guard_pages();
2117 2117 // warning("Guarding at " PTR_FORMAT " for len " SIZE_FORMAT "\n", low_addr, len);
2118 2118
2119 2119 if (allocate && !os::commit_memory((char *) low_addr, len)) {
2120 2120 warning("Attempt to allocate stack guard pages failed.");
2121 2121 return;
2122 2122 }
2123 2123
2124 2124 if (os::guard_memory((char *) low_addr, len)) {
2125 2125 _stack_guard_state = stack_guard_enabled;
2126 2126 } else {
2127 2127 warning("Attempt to protect stack guard pages failed.");
2128 2128 if (os::uncommit_memory((char *) low_addr, len)) {
2129 2129 warning("Attempt to deallocate stack guard pages failed.");
2130 2130 }
2131 2131 }
2132 2132 }
2133 2133
2134 2134 void JavaThread::remove_stack_guard_pages() {
2135 2135 if (_stack_guard_state == stack_guard_unused) return;
2136 2136 address low_addr = stack_base() - stack_size();
2137 2137 size_t len = (StackYellowPages + StackRedPages) * os::vm_page_size();
2138 2138
2139 2139 if (os::allocate_stack_guard_pages()) {
2140 2140 if (os::uncommit_memory((char *) low_addr, len)) {
2141 2141 _stack_guard_state = stack_guard_unused;
2142 2142 } else {
2143 2143 warning("Attempt to deallocate stack guard pages failed.");
2144 2144 }
2145 2145 } else {
2146 2146 if (_stack_guard_state == stack_guard_unused) return;
2147 2147 if (os::unguard_memory((char *) low_addr, len)) {
2148 2148 _stack_guard_state = stack_guard_unused;
2149 2149 } else {
2150 2150 warning("Attempt to unprotect stack guard pages failed.");
2151 2151 }
2152 2152 }
2153 2153 }
2154 2154
2155 2155 void JavaThread::enable_stack_yellow_zone() {
2156 2156 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
2157 2157 assert(_stack_guard_state != stack_guard_enabled, "already enabled");
2158 2158
2159 2159 // The base notation is from the stacks point of view, growing downward.
2160 2160 // We need to adjust it to work correctly with guard_memory()
2161 2161 address base = stack_yellow_zone_base() - stack_yellow_zone_size();
2162 2162
2163 2163 guarantee(base < stack_base(),"Error calculating stack yellow zone");
2164 2164 guarantee(base < os::current_stack_pointer(),"Error calculating stack yellow zone");
2165 2165
2166 2166 if (os::guard_memory((char *) base, stack_yellow_zone_size())) {
2167 2167 _stack_guard_state = stack_guard_enabled;
2168 2168 } else {
2169 2169 warning("Attempt to guard stack yellow zone failed.");
2170 2170 }
2171 2171 enable_register_stack_guard();
2172 2172 }
2173 2173
2174 2174 void JavaThread::disable_stack_yellow_zone() {
2175 2175 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
2176 2176 assert(_stack_guard_state != stack_guard_yellow_disabled, "already disabled");
2177 2177
2178 2178 // Simply return if called for a thread that does not use guard pages.
2179 2179 if (_stack_guard_state == stack_guard_unused) return;
2180 2180
2181 2181 // The base notation is from the stacks point of view, growing downward.
2182 2182 // We need to adjust it to work correctly with guard_memory()
2183 2183 address base = stack_yellow_zone_base() - stack_yellow_zone_size();
2184 2184
2185 2185 if (os::unguard_memory((char *)base, stack_yellow_zone_size())) {
2186 2186 _stack_guard_state = stack_guard_yellow_disabled;
2187 2187 } else {
2188 2188 warning("Attempt to unguard stack yellow zone failed.");
2189 2189 }
2190 2190 disable_register_stack_guard();
2191 2191 }
2192 2192
2193 2193 void JavaThread::enable_stack_red_zone() {
2194 2194 // The base notation is from the stacks point of view, growing downward.
2195 2195 // We need to adjust it to work correctly with guard_memory()
2196 2196 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
2197 2197 address base = stack_red_zone_base() - stack_red_zone_size();
2198 2198
2199 2199 guarantee(base < stack_base(),"Error calculating stack red zone");
2200 2200 guarantee(base < os::current_stack_pointer(),"Error calculating stack red zone");
2201 2201
2202 2202 if(!os::guard_memory((char *) base, stack_red_zone_size())) {
2203 2203 warning("Attempt to guard stack red zone failed.");
2204 2204 }
2205 2205 }
2206 2206
2207 2207 void JavaThread::disable_stack_red_zone() {
2208 2208 // The base notation is from the stacks point of view, growing downward.
2209 2209 // We need to adjust it to work correctly with guard_memory()
2210 2210 assert(_stack_guard_state != stack_guard_unused, "must be using guard pages.");
2211 2211 address base = stack_red_zone_base() - stack_red_zone_size();
2212 2212 if (!os::unguard_memory((char *)base, stack_red_zone_size())) {
2213 2213 warning("Attempt to unguard stack red zone failed.");
2214 2214 }
2215 2215 }
2216 2216
2217 2217 void JavaThread::frames_do(void f(frame*, const RegisterMap* map)) {
2218 2218 // ignore is there is no stack
2219 2219 if (!has_last_Java_frame()) return;
2220 2220 // traverse the stack frames. Starts from top frame.
2221 2221 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
2222 2222 frame* fr = fst.current();
2223 2223 f(fr, fst.register_map());
2224 2224 }
2225 2225 }
2226 2226
2227 2227
2228 2228 #ifndef PRODUCT
2229 2229 // Deoptimization
2230 2230 // Function for testing deoptimization
2231 2231 void JavaThread::deoptimize() {
2232 2232 // BiasedLocking needs an updated RegisterMap for the revoke monitors pass
2233 2233 StackFrameStream fst(this, UseBiasedLocking);
2234 2234 bool deopt = false; // Dump stack only if a deopt actually happens.
2235 2235 bool only_at = strlen(DeoptimizeOnlyAt) > 0;
2236 2236 // Iterate over all frames in the thread and deoptimize
2237 2237 for(; !fst.is_done(); fst.next()) {
2238 2238 if(fst.current()->can_be_deoptimized()) {
2239 2239
2240 2240 if (only_at) {
2241 2241 // Deoptimize only at particular bcis. DeoptimizeOnlyAt
2242 2242 // consists of comma or carriage return separated numbers so
2243 2243 // search for the current bci in that string.
2244 2244 address pc = fst.current()->pc();
2245 2245 nmethod* nm = (nmethod*) fst.current()->cb();
2246 2246 ScopeDesc* sd = nm->scope_desc_at( pc);
2247 2247 char buffer[8];
2248 2248 jio_snprintf(buffer, sizeof(buffer), "%d", sd->bci());
2249 2249 size_t len = strlen(buffer);
2250 2250 const char * found = strstr(DeoptimizeOnlyAt, buffer);
2251 2251 while (found != NULL) {
2252 2252 if ((found[len] == ',' || found[len] == '\n' || found[len] == '\0') &&
2253 2253 (found == DeoptimizeOnlyAt || found[-1] == ',' || found[-1] == '\n')) {
2254 2254 // Check that the bci found is bracketed by terminators.
2255 2255 break;
2256 2256 }
2257 2257 found = strstr(found + 1, buffer);
2258 2258 }
2259 2259 if (!found) {
2260 2260 continue;
2261 2261 }
2262 2262 }
2263 2263
2264 2264 if (DebugDeoptimization && !deopt) {
2265 2265 deopt = true; // One-time only print before deopt
2266 2266 tty->print_cr("[BEFORE Deoptimization]");
2267 2267 trace_frames();
2268 2268 trace_stack();
2269 2269 }
2270 2270 Deoptimization::deoptimize(this, *fst.current(), fst.register_map());
2271 2271 }
2272 2272 }
2273 2273
2274 2274 if (DebugDeoptimization && deopt) {
2275 2275 tty->print_cr("[AFTER Deoptimization]");
2276 2276 trace_frames();
2277 2277 }
2278 2278 }
2279 2279
2280 2280
2281 2281 // Make zombies
2282 2282 void JavaThread::make_zombies() {
2283 2283 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
2284 2284 if (fst.current()->can_be_deoptimized()) {
2285 2285 // it is a Java nmethod
2286 2286 nmethod* nm = CodeCache::find_nmethod(fst.current()->pc());
2287 2287 nm->make_not_entrant();
2288 2288 }
2289 2289 }
2290 2290 }
2291 2291 #endif // PRODUCT
2292 2292
2293 2293
2294 2294 void JavaThread::deoptimized_wrt_marked_nmethods() {
2295 2295 if (!has_last_Java_frame()) return;
2296 2296 // BiasedLocking needs an updated RegisterMap for the revoke monitors pass
2297 2297 StackFrameStream fst(this, UseBiasedLocking);
2298 2298 for(; !fst.is_done(); fst.next()) {
2299 2299 if (fst.current()->should_be_deoptimized()) {
2300 2300 Deoptimization::deoptimize(this, *fst.current(), fst.register_map());
2301 2301 }
2302 2302 }
2303 2303 }
2304 2304
2305 2305
2306 2306 // GC support
2307 2307 static void frame_gc_epilogue(frame* f, const RegisterMap* map) { f->gc_epilogue(); }
2308 2308
2309 2309 void JavaThread::gc_epilogue() {
2310 2310 frames_do(frame_gc_epilogue);
2311 2311 }
2312 2312
2313 2313
2314 2314 static void frame_gc_prologue(frame* f, const RegisterMap* map) { f->gc_prologue(); }
2315 2315
2316 2316 void JavaThread::gc_prologue() {
2317 2317 frames_do(frame_gc_prologue);
2318 2318 }
2319 2319
2320 2320
2321 2321 void JavaThread::oops_do(OopClosure* f, CodeBlobClosure* cf) {
2322 2322 // Flush deferred store-barriers, if any, associated with
2323 2323 // initializing stores done by this JavaThread in the current epoch.
2324 2324 Universe::heap()->flush_deferred_store_barrier(this);
2325 2325
2326 2326 // The ThreadProfiler oops_do is done from FlatProfiler::oops_do
2327 2327 // since there may be more than one thread using each ThreadProfiler.
2328 2328
2329 2329 // Traverse the GCHandles
2330 2330 Thread::oops_do(f, cf);
2331 2331
2332 2332 assert( (!has_last_Java_frame() && java_call_counter() == 0) ||
2333 2333 (has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
2334 2334
2335 2335 if (has_last_Java_frame()) {
2336 2336
2337 2337 // Traverse the privileged stack
2338 2338 if (_privileged_stack_top != NULL) {
2339 2339 _privileged_stack_top->oops_do(f);
2340 2340 }
2341 2341
2342 2342 // traverse the registered growable array
2343 2343 if (_array_for_gc != NULL) {
2344 2344 for (int index = 0; index < _array_for_gc->length(); index++) {
2345 2345 f->do_oop(_array_for_gc->adr_at(index));
2346 2346 }
2347 2347 }
2348 2348
2349 2349 // Traverse the monitor chunks
2350 2350 for (MonitorChunk* chunk = monitor_chunks(); chunk != NULL; chunk = chunk->next()) {
2351 2351 chunk->oops_do(f);
2352 2352 }
2353 2353
2354 2354 // Traverse the execution stack
2355 2355 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
2356 2356 fst.current()->oops_do(f, cf, fst.register_map());
2357 2357 }
2358 2358 }
2359 2359
2360 2360 // callee_target is never live across a gc point so NULL it here should
2361 2361 // it still contain a methdOop.
2362 2362
2363 2363 set_callee_target(NULL);
2364 2364
2365 2365 assert(vframe_array_head() == NULL, "deopt in progress at a safepoint!");
2366 2366 // If we have deferred set_locals there might be oops waiting to be
2367 2367 // written
2368 2368 GrowableArray<jvmtiDeferredLocalVariableSet*>* list = deferred_locals();
2369 2369 if (list != NULL) {
2370 2370 for (int i = 0; i < list->length(); i++) {
2371 2371 list->at(i)->oops_do(f);
2372 2372 }
2373 2373 }
2374 2374
2375 2375 // Traverse instance variables at the end since the GC may be moving things
2376 2376 // around using this function
2377 2377 f->do_oop((oop*) &_threadObj);
2378 2378 f->do_oop((oop*) &_vm_result);
2379 2379 f->do_oop((oop*) &_vm_result_2);
2380 2380 f->do_oop((oop*) &_exception_oop);
2381 2381 f->do_oop((oop*) &_pending_async_exception);
2382 2382
2383 2383 if (jvmti_thread_state() != NULL) {
2384 2384 jvmti_thread_state()->oops_do(f);
2385 2385 }
2386 2386 }
2387 2387
2388 2388 void JavaThread::nmethods_do(CodeBlobClosure* cf) {
2389 2389 Thread::nmethods_do(cf); // (super method is a no-op)
2390 2390
2391 2391 assert( (!has_last_Java_frame() && java_call_counter() == 0) ||
2392 2392 (has_last_Java_frame() && java_call_counter() > 0), "wrong java_sp info!");
2393 2393
2394 2394 if (has_last_Java_frame()) {
2395 2395 // Traverse the execution stack
2396 2396 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
2397 2397 fst.current()->nmethods_do(cf);
2398 2398 }
2399 2399 }
2400 2400 }
2401 2401
2402 2402 // Printing
2403 2403 const char* _get_thread_state_name(JavaThreadState _thread_state) {
2404 2404 switch (_thread_state) {
2405 2405 case _thread_uninitialized: return "_thread_uninitialized";
2406 2406 case _thread_new: return "_thread_new";
2407 2407 case _thread_new_trans: return "_thread_new_trans";
2408 2408 case _thread_in_native: return "_thread_in_native";
2409 2409 case _thread_in_native_trans: return "_thread_in_native_trans";
2410 2410 case _thread_in_vm: return "_thread_in_vm";
2411 2411 case _thread_in_vm_trans: return "_thread_in_vm_trans";
2412 2412 case _thread_in_Java: return "_thread_in_Java";
2413 2413 case _thread_in_Java_trans: return "_thread_in_Java_trans";
2414 2414 case _thread_blocked: return "_thread_blocked";
2415 2415 case _thread_blocked_trans: return "_thread_blocked_trans";
2416 2416 default: return "unknown thread state";
2417 2417 }
2418 2418 }
2419 2419
2420 2420 #ifndef PRODUCT
2421 2421 void JavaThread::print_thread_state_on(outputStream *st) const {
2422 2422 st->print_cr(" JavaThread state: %s", _get_thread_state_name(_thread_state));
2423 2423 };
2424 2424 void JavaThread::print_thread_state() const {
2425 2425 print_thread_state_on(tty);
2426 2426 };
2427 2427 #endif // PRODUCT
2428 2428
2429 2429 // Called by Threads::print() for VM_PrintThreads operation
2430 2430 void JavaThread::print_on(outputStream *st) const {
2431 2431 st->print("\"%s\" ", get_thread_name());
2432 2432 oop thread_oop = threadObj();
2433 2433 if (thread_oop != NULL && java_lang_Thread::is_daemon(thread_oop)) st->print("daemon ");
2434 2434 Thread::print_on(st);
2435 2435 // print guess for valid stack memory region (assume 4K pages); helps lock debugging
2436 2436 st->print_cr("[" INTPTR_FORMAT "]", (intptr_t)last_Java_sp() & ~right_n_bits(12));
2437 2437 if (thread_oop != NULL && JDK_Version::is_gte_jdk15x_version()) {
2438 2438 st->print_cr(" java.lang.Thread.State: %s", java_lang_Thread::thread_status_name(thread_oop));
2439 2439 }
2440 2440 #ifndef PRODUCT
2441 2441 print_thread_state_on(st);
2442 2442 _safepoint_state->print_on(st);
2443 2443 #endif // PRODUCT
2444 2444 }
2445 2445
2446 2446 // Called by fatal error handler. The difference between this and
2447 2447 // JavaThread::print() is that we can't grab lock or allocate memory.
2448 2448 void JavaThread::print_on_error(outputStream* st, char *buf, int buflen) const {
2449 2449 st->print("JavaThread \"%s\"", get_thread_name_string(buf, buflen));
2450 2450 oop thread_obj = threadObj();
2451 2451 if (thread_obj != NULL) {
2452 2452 if (java_lang_Thread::is_daemon(thread_obj)) st->print(" daemon");
2453 2453 }
2454 2454 st->print(" [");
2455 2455 st->print("%s", _get_thread_state_name(_thread_state));
2456 2456 if (osthread()) {
2457 2457 st->print(", id=%d", osthread()->thread_id());
2458 2458 }
2459 2459 st->print(", stack(" PTR_FORMAT "," PTR_FORMAT ")",
2460 2460 _stack_base - _stack_size, _stack_base);
2461 2461 st->print("]");
2462 2462 return;
2463 2463 }
2464 2464
2465 2465 // Verification
2466 2466
2467 2467 static void frame_verify(frame* f, const RegisterMap *map) { f->verify(map); }
2468 2468
2469 2469 void JavaThread::verify() {
2470 2470 // Verify oops in the thread.
2471 2471 oops_do(&VerifyOopClosure::verify_oop, NULL);
2472 2472
2473 2473 // Verify the stack frames.
2474 2474 frames_do(frame_verify);
2475 2475 }
2476 2476
2477 2477 // CR 6300358 (sub-CR 2137150)
2478 2478 // Most callers of this method assume that it can't return NULL but a
2479 2479 // thread may not have a name whilst it is in the process of attaching to
2480 2480 // the VM - see CR 6412693, and there are places where a JavaThread can be
2481 2481 // seen prior to having it's threadObj set (eg JNI attaching threads and
2482 2482 // if vm exit occurs during initialization). These cases can all be accounted
2483 2483 // for such that this method never returns NULL.
2484 2484 const char* JavaThread::get_thread_name() const {
2485 2485 #ifdef ASSERT
2486 2486 // early safepoints can hit while current thread does not yet have TLS
2487 2487 if (!SafepointSynchronize::is_at_safepoint()) {
2488 2488 Thread *cur = Thread::current();
2489 2489 if (!(cur->is_Java_thread() && cur == this)) {
2490 2490 // Current JavaThreads are allowed to get their own name without
2491 2491 // the Threads_lock.
2492 2492 assert_locked_or_safepoint(Threads_lock);
2493 2493 }
2494 2494 }
2495 2495 #endif // ASSERT
2496 2496 return get_thread_name_string();
2497 2497 }
2498 2498
2499 2499 // Returns a non-NULL representation of this thread's name, or a suitable
2500 2500 // descriptive string if there is no set name
2501 2501 const char* JavaThread::get_thread_name_string(char* buf, int buflen) const {
2502 2502 const char* name_str;
2503 2503 oop thread_obj = threadObj();
2504 2504 if (thread_obj != NULL) {
2505 2505 typeArrayOop name = java_lang_Thread::name(thread_obj);
2506 2506 if (name != NULL) {
2507 2507 if (buf == NULL) {
2508 2508 name_str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
2509 2509 }
2510 2510 else {
2511 2511 name_str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length(), buf, buflen);
2512 2512 }
2513 2513 }
2514 2514 else if (is_attaching()) { // workaround for 6412693 - see 6404306
2515 2515 name_str = "<no-name - thread is attaching>";
2516 2516 }
2517 2517 else {
2518 2518 name_str = Thread::name();
2519 2519 }
2520 2520 }
2521 2521 else {
2522 2522 name_str = Thread::name();
2523 2523 }
2524 2524 assert(name_str != NULL, "unexpected NULL thread name");
2525 2525 return name_str;
2526 2526 }
2527 2527
2528 2528
2529 2529 const char* JavaThread::get_threadgroup_name() const {
2530 2530 debug_only(if (JavaThread::current() != this) assert_locked_or_safepoint(Threads_lock);)
2531 2531 oop thread_obj = threadObj();
2532 2532 if (thread_obj != NULL) {
2533 2533 oop thread_group = java_lang_Thread::threadGroup(thread_obj);
2534 2534 if (thread_group != NULL) {
2535 2535 typeArrayOop name = java_lang_ThreadGroup::name(thread_group);
2536 2536 // ThreadGroup.name can be null
2537 2537 if (name != NULL) {
2538 2538 const char* str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
2539 2539 return str;
2540 2540 }
2541 2541 }
2542 2542 }
2543 2543 return NULL;
2544 2544 }
2545 2545
2546 2546 const char* JavaThread::get_parent_name() const {
2547 2547 debug_only(if (JavaThread::current() != this) assert_locked_or_safepoint(Threads_lock);)
2548 2548 oop thread_obj = threadObj();
2549 2549 if (thread_obj != NULL) {
2550 2550 oop thread_group = java_lang_Thread::threadGroup(thread_obj);
2551 2551 if (thread_group != NULL) {
2552 2552 oop parent = java_lang_ThreadGroup::parent(thread_group);
2553 2553 if (parent != NULL) {
2554 2554 typeArrayOop name = java_lang_ThreadGroup::name(parent);
2555 2555 // ThreadGroup.name can be null
2556 2556 if (name != NULL) {
2557 2557 const char* str = UNICODE::as_utf8((jchar*) name->base(T_CHAR), name->length());
2558 2558 return str;
2559 2559 }
2560 2560 }
2561 2561 }
2562 2562 }
2563 2563 return NULL;
2564 2564 }
2565 2565
2566 2566 ThreadPriority JavaThread::java_priority() const {
2567 2567 oop thr_oop = threadObj();
2568 2568 if (thr_oop == NULL) return NormPriority; // Bootstrapping
2569 2569 ThreadPriority priority = java_lang_Thread::priority(thr_oop);
2570 2570 assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
2571 2571 return priority;
2572 2572 }
2573 2573
2574 2574 void JavaThread::prepare(jobject jni_thread, ThreadPriority prio) {
2575 2575
2576 2576 assert(Threads_lock->owner() == Thread::current(), "must have threads lock");
2577 2577 // Link Java Thread object <-> C++ Thread
2578 2578
2579 2579 // Get the C++ thread object (an oop) from the JNI handle (a jthread)
2580 2580 // and put it into a new Handle. The Handle "thread_oop" can then
2581 2581 // be used to pass the C++ thread object to other methods.
2582 2582
2583 2583 // Set the Java level thread object (jthread) field of the
2584 2584 // new thread (a JavaThread *) to C++ thread object using the
2585 2585 // "thread_oop" handle.
2586 2586
2587 2587 // Set the thread field (a JavaThread *) of the
2588 2588 // oop representing the java_lang_Thread to the new thread (a JavaThread *).
2589 2589
2590 2590 Handle thread_oop(Thread::current(),
2591 2591 JNIHandles::resolve_non_null(jni_thread));
2592 2592 assert(instanceKlass::cast(thread_oop->klass())->is_linked(),
2593 2593 "must be initialized");
2594 2594 set_threadObj(thread_oop());
2595 2595 java_lang_Thread::set_thread(thread_oop(), this);
2596 2596
2597 2597 if (prio == NoPriority) {
2598 2598 prio = java_lang_Thread::priority(thread_oop());
2599 2599 assert(prio != NoPriority, "A valid priority should be present");
2600 2600 }
2601 2601
2602 2602 // Push the Java priority down to the native thread; needs Threads_lock
2603 2603 Thread::set_priority(this, prio);
2604 2604
2605 2605 // Add the new thread to the Threads list and set it in motion.
2606 2606 // We must have threads lock in order to call Threads::add.
2607 2607 // It is crucial that we do not block before the thread is
2608 2608 // added to the Threads list for if a GC happens, then the java_thread oop
2609 2609 // will not be visited by GC.
2610 2610 Threads::add(this);
2611 2611 }
2612 2612
2613 2613 oop JavaThread::current_park_blocker() {
2614 2614 // Support for JSR-166 locks
2615 2615 oop thread_oop = threadObj();
2616 2616 if (thread_oop != NULL &&
2617 2617 JDK_Version::current().supports_thread_park_blocker()) {
2618 2618 return java_lang_Thread::park_blocker(thread_oop);
2619 2619 }
2620 2620 return NULL;
2621 2621 }
2622 2622
2623 2623
2624 2624 void JavaThread::print_stack_on(outputStream* st) {
2625 2625 if (!has_last_Java_frame()) return;
2626 2626 ResourceMark rm;
2627 2627 HandleMark hm;
2628 2628
2629 2629 RegisterMap reg_map(this);
2630 2630 vframe* start_vf = last_java_vframe(®_map);
2631 2631 int count = 0;
2632 2632 for (vframe* f = start_vf; f; f = f->sender() ) {
2633 2633 if (f->is_java_frame()) {
2634 2634 javaVFrame* jvf = javaVFrame::cast(f);
2635 2635 java_lang_Throwable::print_stack_element(st, jvf->method(), jvf->bci());
2636 2636
2637 2637 // Print out lock information
2638 2638 if (JavaMonitorsInStackTrace) {
2639 2639 jvf->print_lock_info_on(st, count);
2640 2640 }
2641 2641 } else {
2642 2642 // Ignore non-Java frames
2643 2643 }
2644 2644
2645 2645 // Bail-out case for too deep stacks
2646 2646 count++;
2647 2647 if (MaxJavaStackTraceDepth == count) return;
2648 2648 }
2649 2649 }
2650 2650
2651 2651
2652 2652 // JVMTI PopFrame support
2653 2653 void JavaThread::popframe_preserve_args(ByteSize size_in_bytes, void* start) {
2654 2654 assert(_popframe_preserved_args == NULL, "should not wipe out old PopFrame preserved arguments");
2655 2655 if (in_bytes(size_in_bytes) != 0) {
2656 2656 _popframe_preserved_args = NEW_C_HEAP_ARRAY(char, in_bytes(size_in_bytes));
2657 2657 _popframe_preserved_args_size = in_bytes(size_in_bytes);
2658 2658 Copy::conjoint_bytes(start, _popframe_preserved_args, _popframe_preserved_args_size);
2659 2659 }
2660 2660 }
2661 2661
2662 2662 void* JavaThread::popframe_preserved_args() {
2663 2663 return _popframe_preserved_args;
2664 2664 }
2665 2665
2666 2666 ByteSize JavaThread::popframe_preserved_args_size() {
2667 2667 return in_ByteSize(_popframe_preserved_args_size);
2668 2668 }
2669 2669
2670 2670 WordSize JavaThread::popframe_preserved_args_size_in_words() {
2671 2671 int sz = in_bytes(popframe_preserved_args_size());
2672 2672 assert(sz % wordSize == 0, "argument size must be multiple of wordSize");
2673 2673 return in_WordSize(sz / wordSize);
2674 2674 }
2675 2675
2676 2676 void JavaThread::popframe_free_preserved_args() {
2677 2677 assert(_popframe_preserved_args != NULL, "should not free PopFrame preserved arguments twice");
2678 2678 FREE_C_HEAP_ARRAY(char, (char*) _popframe_preserved_args);
2679 2679 _popframe_preserved_args = NULL;
2680 2680 _popframe_preserved_args_size = 0;
2681 2681 }
2682 2682
2683 2683 #ifndef PRODUCT
2684 2684
2685 2685 void JavaThread::trace_frames() {
2686 2686 tty->print_cr("[Describe stack]");
2687 2687 int frame_no = 1;
2688 2688 for(StackFrameStream fst(this); !fst.is_done(); fst.next()) {
2689 2689 tty->print(" %d. ", frame_no++);
2690 2690 fst.current()->print_value_on(tty,this);
2691 2691 tty->cr();
2692 2692 }
2693 2693 }
2694 2694
2695 2695
2696 2696 void JavaThread::trace_stack_from(vframe* start_vf) {
2697 2697 ResourceMark rm;
2698 2698 int vframe_no = 1;
2699 2699 for (vframe* f = start_vf; f; f = f->sender() ) {
2700 2700 if (f->is_java_frame()) {
2701 2701 javaVFrame::cast(f)->print_activation(vframe_no++);
2702 2702 } else {
2703 2703 f->print();
2704 2704 }
2705 2705 if (vframe_no > StackPrintLimit) {
2706 2706 tty->print_cr("...<more frames>...");
2707 2707 return;
2708 2708 }
2709 2709 }
2710 2710 }
2711 2711
2712 2712
2713 2713 void JavaThread::trace_stack() {
2714 2714 if (!has_last_Java_frame()) return;
2715 2715 ResourceMark rm;
2716 2716 HandleMark hm;
2717 2717 RegisterMap reg_map(this);
2718 2718 trace_stack_from(last_java_vframe(®_map));
2719 2719 }
2720 2720
2721 2721
2722 2722 #endif // PRODUCT
2723 2723
2724 2724
2725 2725 javaVFrame* JavaThread::last_java_vframe(RegisterMap *reg_map) {
2726 2726 assert(reg_map != NULL, "a map must be given");
2727 2727 frame f = last_frame();
2728 2728 for (vframe* vf = vframe::new_vframe(&f, reg_map, this); vf; vf = vf->sender() ) {
2729 2729 if (vf->is_java_frame()) return javaVFrame::cast(vf);
2730 2730 }
2731 2731 return NULL;
2732 2732 }
2733 2733
2734 2734
2735 2735 klassOop JavaThread::security_get_caller_class(int depth) {
2736 2736 vframeStream vfst(this);
2737 2737 vfst.security_get_caller_frame(depth);
2738 2738 if (!vfst.at_end()) {
2739 2739 return vfst.method()->method_holder();
2740 2740 }
2741 2741 return NULL;
2742 2742 }
2743 2743
2744 2744 static void compiler_thread_entry(JavaThread* thread, TRAPS) {
2745 2745 assert(thread->is_Compiler_thread(), "must be compiler thread");
2746 2746 CompileBroker::compiler_thread_loop();
2747 2747 }
2748 2748
2749 2749 // Create a CompilerThread
2750 2750 CompilerThread::CompilerThread(CompileQueue* queue, CompilerCounters* counters)
2751 2751 : JavaThread(&compiler_thread_entry) {
2752 2752 _env = NULL;
2753 2753 _log = NULL;
2754 2754 _task = NULL;
2755 2755 _queue = queue;
2756 2756 _counters = counters;
2757 2757
2758 2758 #ifndef PRODUCT
2759 2759 _ideal_graph_printer = NULL;
2760 2760 #endif
2761 2761 }
2762 2762
2763 2763
2764 2764 // ======= Threads ========
2765 2765
2766 2766 // The Threads class links together all active threads, and provides
2767 2767 // operations over all threads. It is protected by its own Mutex
2768 2768 // lock, which is also used in other contexts to protect thread
2769 2769 // operations from having the thread being operated on from exiting
2770 2770 // and going away unexpectedly (e.g., safepoint synchronization)
2771 2771
2772 2772 JavaThread* Threads::_thread_list = NULL;
2773 2773 int Threads::_number_of_threads = 0;
2774 2774 int Threads::_number_of_non_daemon_threads = 0;
2775 2775 int Threads::_return_code = 0;
2776 2776 size_t JavaThread::_stack_size_at_create = 0;
2777 2777
2778 2778 // All JavaThreads
2779 2779 #define ALL_JAVA_THREADS(X) for (JavaThread* X = _thread_list; X; X = X->next())
2780 2780
2781 2781 void os_stream();
2782 2782
2783 2783 // All JavaThreads + all non-JavaThreads (i.e., every thread in the system)
2784 2784 void Threads::threads_do(ThreadClosure* tc) {
2785 2785 assert_locked_or_safepoint(Threads_lock);
2786 2786 // ALL_JAVA_THREADS iterates through all JavaThreads
2787 2787 ALL_JAVA_THREADS(p) {
2788 2788 tc->do_thread(p);
2789 2789 }
2790 2790 // Someday we could have a table or list of all non-JavaThreads.
2791 2791 // For now, just manually iterate through them.
2792 2792 tc->do_thread(VMThread::vm_thread());
2793 2793 Universe::heap()->gc_threads_do(tc);
2794 2794 WatcherThread *wt = WatcherThread::watcher_thread();
2795 2795 // Strictly speaking, the following NULL check isn't sufficient to make sure
2796 2796 // the data for WatcherThread is still valid upon being examined. However,
2797 2797 // considering that WatchThread terminates when the VM is on the way to
2798 2798 // exit at safepoint, the chance of the above is extremely small. The right
2799 2799 // way to prevent termination of WatcherThread would be to acquire
2800 2800 // Terminator_lock, but we can't do that without violating the lock rank
2801 2801 // checking in some cases.
2802 2802 if (wt != NULL)
2803 2803 tc->do_thread(wt);
2804 2804
2805 2805 // If CompilerThreads ever become non-JavaThreads, add them here
2806 2806 }
2807 2807
2808 2808 jint Threads::create_vm(JavaVMInitArgs* args, bool* canTryAgain) {
2809 2809
2810 2810 extern void JDK_Version_init();
2811 2811
2812 2812 // Check version
2813 2813 if (!is_supported_jni_version(args->version)) return JNI_EVERSION;
2814 2814
2815 2815 // Initialize the output stream module
2816 2816 ostream_init();
2817 2817
2818 2818 // Process java launcher properties.
2819 2819 Arguments::process_sun_java_launcher_properties(args);
2820 2820
2821 2821 // Initialize the os module before using TLS
2822 2822 os::init();
2823 2823
2824 2824 // Initialize system properties.
2825 2825 Arguments::init_system_properties();
2826 2826
2827 2827 // So that JDK version can be used as a discrimintor when parsing arguments
2828 2828 JDK_Version_init();
2829 2829
2830 2830 // Parse arguments
2831 2831 jint parse_result = Arguments::parse(args);
2832 2832 if (parse_result != JNI_OK) return parse_result;
2833 2833
2834 2834 if (PauseAtStartup) {
2835 2835 os::pause();
2836 2836 }
2837 2837
2838 2838 HS_DTRACE_PROBE(hotspot, vm__init__begin);
2839 2839
2840 2840 // Record VM creation timing statistics
2841 2841 TraceVmCreationTime create_vm_timer;
2842 2842 create_vm_timer.start();
2843 2843
2844 2844 // Timing (must come after argument parsing)
2845 2845 TraceTime timer("Create VM", TraceStartupTime);
2846 2846
2847 2847 // Initialize the os module after parsing the args
2848 2848 jint os_init_2_result = os::init_2();
2849 2849 if (os_init_2_result != JNI_OK) return os_init_2_result;
2850 2850
2851 2851 // Initialize output stream logging
2852 2852 ostream_init_log();
2853 2853
2854 2854 // Convert -Xrun to -agentlib: if there is no JVM_OnLoad
2855 2855 // Must be before create_vm_init_agents()
2856 2856 if (Arguments::init_libraries_at_startup()) {
2857 2857 convert_vm_init_libraries_to_agents();
2858 2858 }
2859 2859
2860 2860 // Launch -agentlib/-agentpath and converted -Xrun agents
2861 2861 if (Arguments::init_agents_at_startup()) {
2862 2862 create_vm_init_agents();
2863 2863 }
2864 2864
2865 2865 // Initialize Threads state
2866 2866 _thread_list = NULL;
2867 2867 _number_of_threads = 0;
2868 2868 _number_of_non_daemon_threads = 0;
2869 2869
2870 2870 // Initialize TLS
2871 2871 ThreadLocalStorage::init();
2872 2872
2873 2873 // Initialize global data structures and create system classes in heap
2874 2874 vm_init_globals();
2875 2875
2876 2876 // Attach the main thread to this os thread
2877 2877 JavaThread* main_thread = new JavaThread();
2878 2878 main_thread->set_thread_state(_thread_in_vm);
2879 2879 // must do this before set_active_handles and initialize_thread_local_storage
2880 2880 // Note: on solaris initialize_thread_local_storage() will (indirectly)
2881 2881 // change the stack size recorded here to one based on the java thread
2882 2882 // stacksize. This adjusted size is what is used to figure the placement
2883 2883 // of the guard pages.
2884 2884 main_thread->record_stack_base_and_size();
2885 2885 main_thread->initialize_thread_local_storage();
2886 2886
2887 2887 main_thread->set_active_handles(JNIHandleBlock::allocate_block());
2888 2888
2889 2889 if (!main_thread->set_as_starting_thread()) {
2890 2890 vm_shutdown_during_initialization(
2891 2891 "Failed necessary internal allocation. Out of swap space");
2892 2892 delete main_thread;
2893 2893 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
2894 2894 return JNI_ENOMEM;
2895 2895 }
2896 2896
2897 2897 // Enable guard page *after* os::create_main_thread(), otherwise it would
2898 2898 // crash Linux VM, see notes in os_linux.cpp.
2899 2899 main_thread->create_stack_guard_pages();
2900 2900
2901 2901 // Initialize Java-Leve synchronization subsystem
2902 2902 ObjectSynchronizer::Initialize() ;
2903 2903
2904 2904 // Initialize global modules
2905 2905 jint status = init_globals();
2906 2906 if (status != JNI_OK) {
2907 2907 delete main_thread;
2908 2908 *canTryAgain = false; // don't let caller call JNI_CreateJavaVM again
2909 2909 return status;
2910 2910 }
2911 2911
2912 2912 HandleMark hm;
2913 2913
2914 2914 { MutexLocker mu(Threads_lock);
2915 2915 Threads::add(main_thread);
2916 2916 }
2917 2917
2918 2918 // Any JVMTI raw monitors entered in onload will transition into
2919 2919 // real raw monitor. VM is setup enough here for raw monitor enter.
2920 2920 JvmtiExport::transition_pending_onload_raw_monitors();
2921 2921
2922 2922 if (VerifyBeforeGC &&
2923 2923 Universe::heap()->total_collections() >= VerifyGCStartAt) {
2924 2924 Universe::heap()->prepare_for_verify();
2925 2925 Universe::verify(); // make sure we're starting with a clean slate
2926 2926 }
2927 2927
2928 2928 // Create the VMThread
2929 2929 { TraceTime timer("Start VMThread", TraceStartupTime);
2930 2930 VMThread::create();
2931 2931 Thread* vmthread = VMThread::vm_thread();
2932 2932
2933 2933 if (!os::create_thread(vmthread, os::vm_thread))
2934 2934 vm_exit_during_initialization("Cannot create VM thread. Out of system resources.");
2935 2935
2936 2936 // Wait for the VM thread to become ready, and VMThread::run to initialize
2937 2937 // Monitors can have spurious returns, must always check another state flag
2938 2938 {
2939 2939 MutexLocker ml(Notify_lock);
2940 2940 os::start_thread(vmthread);
2941 2941 while (vmthread->active_handles() == NULL) {
2942 2942 Notify_lock->wait();
2943 2943 }
2944 2944 }
2945 2945 }
2946 2946
2947 2947 assert (Universe::is_fully_initialized(), "not initialized");
2948 2948 EXCEPTION_MARK;
2949 2949
2950 2950 // At this point, the Universe is initialized, but we have not executed
2951 2951 // any byte code. Now is a good time (the only time) to dump out the
2952 2952 // internal state of the JVM for sharing.
2953 2953
2954 2954 if (DumpSharedSpaces) {
2955 2955 Universe::heap()->preload_and_dump(CHECK_0);
2956 2956 ShouldNotReachHere();
2957 2957 }
2958 2958
2959 2959 // Always call even when there are not JVMTI environments yet, since environments
2960 2960 // may be attached late and JVMTI must track phases of VM execution
2961 2961 JvmtiExport::enter_start_phase();
2962 2962
2963 2963 // Notify JVMTI agents that VM has started (JNI is up) - nop if no agents.
2964 2964 JvmtiExport::post_vm_start();
2965 2965
2966 2966 {
2967 2967 TraceTime timer("Initialize java.lang classes", TraceStartupTime);
2968 2968
2969 2969 if (EagerXrunInit && Arguments::init_libraries_at_startup()) {
2970 2970 create_vm_init_libraries();
2971 2971 }
2972 2972
2973 2973 if (InitializeJavaLangString) {
2974 2974 initialize_class(vmSymbolHandles::java_lang_String(), CHECK_0);
2975 2975 } else {
2976 2976 warning("java.lang.String not initialized");
2977 2977 }
2978 2978
2979 2979 if (AggressiveOpts) {
2980 2980 {
2981 2981 // Forcibly initialize java/util/HashMap and mutate the private
2982 2982 // static final "frontCacheEnabled" field before we start creating instances
2983 2983 #ifdef ASSERT
2984 2984 klassOop tmp_k = SystemDictionary::find(vmSymbolHandles::java_util_HashMap(), Handle(), Handle(), CHECK_0);
2985 2985 assert(tmp_k == NULL, "java/util/HashMap should not be loaded yet");
2986 2986 #endif
2987 2987 klassOop k_o = SystemDictionary::resolve_or_null(vmSymbolHandles::java_util_HashMap(), Handle(), Handle(), CHECK_0);
2988 2988 KlassHandle k = KlassHandle(THREAD, k_o);
2989 2989 guarantee(k.not_null(), "Must find java/util/HashMap");
2990 2990 instanceKlassHandle ik = instanceKlassHandle(THREAD, k());
2991 2991 ik->initialize(CHECK_0);
2992 2992 fieldDescriptor fd;
2993 2993 // Possible we might not find this field; if so, don't break
2994 2994 if (ik->find_local_field(vmSymbols::frontCacheEnabled_name(), vmSymbols::bool_signature(), &fd)) {
2995 2995 k()->bool_field_put(fd.offset(), true);
2996 2996 }
2997 2997 }
2998 2998
2999 2999 if (UseStringCache) {
3000 3000 // Forcibly initialize java/lang/StringValue and mutate the private
3001 3001 // static final "stringCacheEnabled" field before we start creating instances
3002 3002 klassOop k_o = SystemDictionary::resolve_or_null(vmSymbolHandles::java_lang_StringValue(), Handle(), Handle(), CHECK_0);
3003 3003 // Possible that StringValue isn't present: if so, silently don't break
3004 3004 if (k_o != NULL) {
3005 3005 KlassHandle k = KlassHandle(THREAD, k_o);
3006 3006 instanceKlassHandle ik = instanceKlassHandle(THREAD, k());
3007 3007 ik->initialize(CHECK_0);
3008 3008 fieldDescriptor fd;
3009 3009 // Possible we might not find this field: if so, silently don't break
3010 3010 if (ik->find_local_field(vmSymbols::stringCacheEnabled_name(), vmSymbols::bool_signature(), &fd)) {
3011 3011 k()->bool_field_put(fd.offset(), true);
3012 3012 }
3013 3013 }
3014 3014 }
3015 3015 }
3016 3016
3017 3017 // Initialize java_lang.System (needed before creating the thread)
3018 3018 if (InitializeJavaLangSystem) {
3019 3019 initialize_class(vmSymbolHandles::java_lang_System(), CHECK_0);
3020 3020 initialize_class(vmSymbolHandles::java_lang_ThreadGroup(), CHECK_0);
3021 3021 Handle thread_group = create_initial_thread_group(CHECK_0);
3022 3022 Universe::set_main_thread_group(thread_group());
3023 3023 initialize_class(vmSymbolHandles::java_lang_Thread(), CHECK_0);
3024 3024 oop thread_object = create_initial_thread(thread_group, main_thread, CHECK_0);
3025 3025 main_thread->set_threadObj(thread_object);
3026 3026 // Set thread status to running since main thread has
3027 3027 // been started and running.
3028 3028 java_lang_Thread::set_thread_status(thread_object,
3029 3029 java_lang_Thread::RUNNABLE);
3030 3030
3031 3031 // The VM preresolve methods to these classes. Make sure that get initialized
3032 3032 initialize_class(vmSymbolHandles::java_lang_reflect_Method(), CHECK_0);
3033 3033 initialize_class(vmSymbolHandles::java_lang_ref_Finalizer(), CHECK_0);
3034 3034 // The VM creates & returns objects of this class. Make sure it's initialized.
3035 3035 initialize_class(vmSymbolHandles::java_lang_Class(), CHECK_0);
3036 3036 call_initializeSystemClass(CHECK_0);
3037 3037 } else {
3038 3038 warning("java.lang.System not initialized");
3039 3039 }
3040 3040
3041 3041 // an instance of OutOfMemory exception has been allocated earlier
3042 3042 if (InitializeJavaLangExceptionsErrors) {
3043 3043 initialize_class(vmSymbolHandles::java_lang_OutOfMemoryError(), CHECK_0);
3044 3044 initialize_class(vmSymbolHandles::java_lang_NullPointerException(), CHECK_0);
3045 3045 initialize_class(vmSymbolHandles::java_lang_ClassCastException(), CHECK_0);
3046 3046 initialize_class(vmSymbolHandles::java_lang_ArrayStoreException(), CHECK_0);
3047 3047 initialize_class(vmSymbolHandles::java_lang_ArithmeticException(), CHECK_0);
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3048 3048 initialize_class(vmSymbolHandles::java_lang_StackOverflowError(), CHECK_0);
3049 3049 initialize_class(vmSymbolHandles::java_lang_IllegalMonitorStateException(), CHECK_0);
3050 3050 } else {
3051 3051 warning("java.lang.OutOfMemoryError has not been initialized");
3052 3052 warning("java.lang.NullPointerException has not been initialized");
3053 3053 warning("java.lang.ClassCastException has not been initialized");
3054 3054 warning("java.lang.ArrayStoreException has not been initialized");
3055 3055 warning("java.lang.ArithmeticException has not been initialized");
3056 3056 warning("java.lang.StackOverflowError has not been initialized");
3057 3057 }
3058 +
3059 + if (EnableInvokeDynamic) {
3060 + // JSR 292: An intialized java.dyn.InvokeDynamic is required in
3061 + // the compiler.
3062 + initialize_class(vmSymbolHandles::java_dyn_InvokeDynamic(), CHECK_0);
3063 + }
3058 3064 }
3059 3065
3060 3066 // See : bugid 4211085.
3061 3067 // Background : the static initializer of java.lang.Compiler tries to read
3062 3068 // property"java.compiler" and read & write property "java.vm.info".
3063 3069 // When a security manager is installed through the command line
3064 3070 // option "-Djava.security.manager", the above properties are not
3065 3071 // readable and the static initializer for java.lang.Compiler fails
3066 3072 // resulting in a NoClassDefFoundError. This can happen in any
3067 3073 // user code which calls methods in java.lang.Compiler.
3068 3074 // Hack : the hack is to pre-load and initialize this class, so that only
3069 3075 // system domains are on the stack when the properties are read.
3070 3076 // Currently even the AWT code has calls to methods in java.lang.Compiler.
3071 3077 // On the classic VM, java.lang.Compiler is loaded very early to load the JIT.
3072 3078 // Future Fix : the best fix is to grant everyone permissions to read "java.compiler" and
3073 3079 // read and write"java.vm.info" in the default policy file. See bugid 4211383
3074 3080 // Once that is done, we should remove this hack.
3075 3081 initialize_class(vmSymbolHandles::java_lang_Compiler(), CHECK_0);
3076 3082
3077 3083 // More hackery - the static initializer of java.lang.Compiler adds the string "nojit" to
3078 3084 // the java.vm.info property if no jit gets loaded through java.lang.Compiler (the hotspot
3079 3085 // compiler does not get loaded through java.lang.Compiler). "java -version" with the
3080 3086 // hotspot vm says "nojit" all the time which is confusing. So, we reset it here.
3081 3087 // This should also be taken out as soon as 4211383 gets fixed.
3082 3088 reset_vm_info_property(CHECK_0);
3083 3089
3084 3090 quicken_jni_functions();
3085 3091
3086 3092 // Set flag that basic initialization has completed. Used by exceptions and various
3087 3093 // debug stuff, that does not work until all basic classes have been initialized.
3088 3094 set_init_completed();
3089 3095
3090 3096 HS_DTRACE_PROBE(hotspot, vm__init__end);
3091 3097
3092 3098 // record VM initialization completion time
3093 3099 Management::record_vm_init_completed();
3094 3100
3095 3101 // Compute system loader. Note that this has to occur after set_init_completed, since
3096 3102 // valid exceptions may be thrown in the process.
3097 3103 // Note that we do not use CHECK_0 here since we are inside an EXCEPTION_MARK and
3098 3104 // set_init_completed has just been called, causing exceptions not to be shortcut
3099 3105 // anymore. We call vm_exit_during_initialization directly instead.
3100 3106 SystemDictionary::compute_java_system_loader(THREAD);
3101 3107 if (HAS_PENDING_EXCEPTION) {
3102 3108 vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
3103 3109 }
3104 3110
3105 3111 #ifndef SERIALGC
3106 3112 // Support for ConcurrentMarkSweep. This should be cleaned up
3107 3113 // and better encapsulated. The ugly nested if test would go away
3108 3114 // once things are properly refactored. XXX YSR
3109 3115 if (UseConcMarkSweepGC || UseG1GC) {
3110 3116 if (UseConcMarkSweepGC) {
3111 3117 ConcurrentMarkSweepThread::makeSurrogateLockerThread(THREAD);
3112 3118 } else {
3113 3119 ConcurrentMarkThread::makeSurrogateLockerThread(THREAD);
3114 3120 }
3115 3121 if (HAS_PENDING_EXCEPTION) {
3116 3122 vm_exit_during_initialization(Handle(THREAD, PENDING_EXCEPTION));
3117 3123 }
3118 3124 }
3119 3125 #endif // SERIALGC
3120 3126
3121 3127 // Always call even when there are not JVMTI environments yet, since environments
3122 3128 // may be attached late and JVMTI must track phases of VM execution
3123 3129 JvmtiExport::enter_live_phase();
3124 3130
3125 3131 // Signal Dispatcher needs to be started before VMInit event is posted
3126 3132 os::signal_init();
3127 3133
3128 3134 // Start Attach Listener if +StartAttachListener or it can't be started lazily
3129 3135 if (!DisableAttachMechanism) {
3130 3136 if (StartAttachListener || AttachListener::init_at_startup()) {
3131 3137 AttachListener::init();
3132 3138 }
3133 3139 }
3134 3140
3135 3141 // Launch -Xrun agents
3136 3142 // Must be done in the JVMTI live phase so that for backward compatibility the JDWP
3137 3143 // back-end can launch with -Xdebug -Xrunjdwp.
3138 3144 if (!EagerXrunInit && Arguments::init_libraries_at_startup()) {
3139 3145 create_vm_init_libraries();
3140 3146 }
3141 3147
3142 3148 // Notify JVMTI agents that VM initialization is complete - nop if no agents.
3143 3149 JvmtiExport::post_vm_initialized();
3144 3150
3145 3151 Chunk::start_chunk_pool_cleaner_task();
3146 3152
3147 3153 // initialize compiler(s)
3148 3154 CompileBroker::compilation_init();
3149 3155
3150 3156 Management::initialize(THREAD);
3151 3157 if (HAS_PENDING_EXCEPTION) {
3152 3158 // management agent fails to start possibly due to
3153 3159 // configuration problem and is responsible for printing
3154 3160 // stack trace if appropriate. Simply exit VM.
3155 3161 vm_exit(1);
3156 3162 }
3157 3163
3158 3164 if (Arguments::has_profile()) FlatProfiler::engage(main_thread, true);
3159 3165 if (Arguments::has_alloc_profile()) AllocationProfiler::engage();
3160 3166 if (MemProfiling) MemProfiler::engage();
3161 3167 StatSampler::engage();
3162 3168 if (CheckJNICalls) JniPeriodicChecker::engage();
3163 3169
3164 3170 BiasedLocking::init();
3165 3171
3166 3172
3167 3173 // Start up the WatcherThread if there are any periodic tasks
3168 3174 // NOTE: All PeriodicTasks should be registered by now. If they
3169 3175 // aren't, late joiners might appear to start slowly (we might
3170 3176 // take a while to process their first tick).
3171 3177 if (PeriodicTask::num_tasks() > 0) {
3172 3178 WatcherThread::start();
3173 3179 }
3174 3180
3175 3181 create_vm_timer.end();
3176 3182 return JNI_OK;
3177 3183 }
3178 3184
3179 3185 // type for the Agent_OnLoad and JVM_OnLoad entry points
3180 3186 extern "C" {
3181 3187 typedef jint (JNICALL *OnLoadEntry_t)(JavaVM *, char *, void *);
3182 3188 }
3183 3189 // Find a command line agent library and return its entry point for
3184 3190 // -agentlib: -agentpath: -Xrun
3185 3191 // num_symbol_entries must be passed-in since only the caller knows the number of symbols in the array.
3186 3192 static OnLoadEntry_t lookup_on_load(AgentLibrary* agent, const char *on_load_symbols[], size_t num_symbol_entries) {
3187 3193 OnLoadEntry_t on_load_entry = NULL;
3188 3194 void *library = agent->os_lib(); // check if we have looked it up before
3189 3195
3190 3196 if (library == NULL) {
3191 3197 char buffer[JVM_MAXPATHLEN];
3192 3198 char ebuf[1024];
3193 3199 const char *name = agent->name();
3194 3200
3195 3201 if (agent->is_absolute_path()) {
3196 3202 library = hpi::dll_load(name, ebuf, sizeof ebuf);
3197 3203 if (library == NULL) {
3198 3204 // If we can't find the agent, exit.
3199 3205 vm_exit_during_initialization("Could not find agent library in absolute path", name);
3200 3206 }
3201 3207 } else {
3202 3208 // Try to load the agent from the standard dll directory
3203 3209 hpi::dll_build_name(buffer, sizeof(buffer), Arguments::get_dll_dir(), name);
3204 3210 library = hpi::dll_load(buffer, ebuf, sizeof ebuf);
3205 3211 #ifdef KERNEL
3206 3212 // Download instrument dll
3207 3213 if (library == NULL && strcmp(name, "instrument") == 0) {
3208 3214 char *props = Arguments::get_kernel_properties();
3209 3215 char *home = Arguments::get_java_home();
3210 3216 const char *fmt = "%s/bin/java %s -Dkernel.background.download=false"
3211 3217 " sun.jkernel.DownloadManager -download client_jvm";
3212 3218 int length = strlen(props) + strlen(home) + strlen(fmt) + 1;
3213 3219 char *cmd = AllocateHeap(length);
3214 3220 jio_snprintf(cmd, length, fmt, home, props);
3215 3221 int status = os::fork_and_exec(cmd);
3216 3222 FreeHeap(props);
3217 3223 FreeHeap(cmd);
3218 3224 if (status == -1) {
3219 3225 warning(cmd);
3220 3226 vm_exit_during_initialization("fork_and_exec failed: %s",
3221 3227 strerror(errno));
3222 3228 }
3223 3229 // when this comes back the instrument.dll should be where it belongs.
3224 3230 library = hpi::dll_load(buffer, ebuf, sizeof ebuf);
3225 3231 }
3226 3232 #endif // KERNEL
3227 3233 if (library == NULL) { // Try the local directory
3228 3234 char ns[1] = {0};
3229 3235 hpi::dll_build_name(buffer, sizeof(buffer), ns, name);
3230 3236 library = hpi::dll_load(buffer, ebuf, sizeof ebuf);
3231 3237 if (library == NULL) {
3232 3238 // If we can't find the agent, exit.
3233 3239 vm_exit_during_initialization("Could not find agent library on the library path or in the local directory", name);
3234 3240 }
3235 3241 }
3236 3242 }
3237 3243 agent->set_os_lib(library);
3238 3244 }
3239 3245
3240 3246 // Find the OnLoad function.
3241 3247 for (size_t symbol_index = 0; symbol_index < num_symbol_entries; symbol_index++) {
3242 3248 on_load_entry = CAST_TO_FN_PTR(OnLoadEntry_t, hpi::dll_lookup(library, on_load_symbols[symbol_index]));
3243 3249 if (on_load_entry != NULL) break;
3244 3250 }
3245 3251 return on_load_entry;
3246 3252 }
3247 3253
3248 3254 // Find the JVM_OnLoad entry point
3249 3255 static OnLoadEntry_t lookup_jvm_on_load(AgentLibrary* agent) {
3250 3256 const char *on_load_symbols[] = JVM_ONLOAD_SYMBOLS;
3251 3257 return lookup_on_load(agent, on_load_symbols, sizeof(on_load_symbols) / sizeof(char*));
3252 3258 }
3253 3259
3254 3260 // Find the Agent_OnLoad entry point
3255 3261 static OnLoadEntry_t lookup_agent_on_load(AgentLibrary* agent) {
3256 3262 const char *on_load_symbols[] = AGENT_ONLOAD_SYMBOLS;
3257 3263 return lookup_on_load(agent, on_load_symbols, sizeof(on_load_symbols) / sizeof(char*));
3258 3264 }
3259 3265
3260 3266 // For backwards compatibility with -Xrun
3261 3267 // Convert libraries with no JVM_OnLoad, but which have Agent_OnLoad to be
3262 3268 // treated like -agentpath:
3263 3269 // Must be called before agent libraries are created
3264 3270 void Threads::convert_vm_init_libraries_to_agents() {
3265 3271 AgentLibrary* agent;
3266 3272 AgentLibrary* next;
3267 3273
3268 3274 for (agent = Arguments::libraries(); agent != NULL; agent = next) {
3269 3275 next = agent->next(); // cache the next agent now as this agent may get moved off this list
3270 3276 OnLoadEntry_t on_load_entry = lookup_jvm_on_load(agent);
3271 3277
3272 3278 // If there is an JVM_OnLoad function it will get called later,
3273 3279 // otherwise see if there is an Agent_OnLoad
3274 3280 if (on_load_entry == NULL) {
3275 3281 on_load_entry = lookup_agent_on_load(agent);
3276 3282 if (on_load_entry != NULL) {
3277 3283 // switch it to the agent list -- so that Agent_OnLoad will be called,
3278 3284 // JVM_OnLoad won't be attempted and Agent_OnUnload will
3279 3285 Arguments::convert_library_to_agent(agent);
3280 3286 } else {
3281 3287 vm_exit_during_initialization("Could not find JVM_OnLoad or Agent_OnLoad function in the library", agent->name());
3282 3288 }
3283 3289 }
3284 3290 }
3285 3291 }
3286 3292
3287 3293 // Create agents for -agentlib: -agentpath: and converted -Xrun
3288 3294 // Invokes Agent_OnLoad
3289 3295 // Called very early -- before JavaThreads exist
3290 3296 void Threads::create_vm_init_agents() {
3291 3297 extern struct JavaVM_ main_vm;
3292 3298 AgentLibrary* agent;
3293 3299
3294 3300 JvmtiExport::enter_onload_phase();
3295 3301 for (agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
3296 3302 OnLoadEntry_t on_load_entry = lookup_agent_on_load(agent);
3297 3303
3298 3304 if (on_load_entry != NULL) {
3299 3305 // Invoke the Agent_OnLoad function
3300 3306 jint err = (*on_load_entry)(&main_vm, agent->options(), NULL);
3301 3307 if (err != JNI_OK) {
3302 3308 vm_exit_during_initialization("agent library failed to init", agent->name());
3303 3309 }
3304 3310 } else {
3305 3311 vm_exit_during_initialization("Could not find Agent_OnLoad function in the agent library", agent->name());
3306 3312 }
3307 3313 }
3308 3314 JvmtiExport::enter_primordial_phase();
3309 3315 }
3310 3316
3311 3317 extern "C" {
3312 3318 typedef void (JNICALL *Agent_OnUnload_t)(JavaVM *);
3313 3319 }
3314 3320
3315 3321 void Threads::shutdown_vm_agents() {
3316 3322 // Send any Agent_OnUnload notifications
3317 3323 const char *on_unload_symbols[] = AGENT_ONUNLOAD_SYMBOLS;
3318 3324 extern struct JavaVM_ main_vm;
3319 3325 for (AgentLibrary* agent = Arguments::agents(); agent != NULL; agent = agent->next()) {
3320 3326
3321 3327 // Find the Agent_OnUnload function.
3322 3328 for (uint symbol_index = 0; symbol_index < ARRAY_SIZE(on_unload_symbols); symbol_index++) {
3323 3329 Agent_OnUnload_t unload_entry = CAST_TO_FN_PTR(Agent_OnUnload_t,
3324 3330 hpi::dll_lookup(agent->os_lib(), on_unload_symbols[symbol_index]));
3325 3331
3326 3332 // Invoke the Agent_OnUnload function
3327 3333 if (unload_entry != NULL) {
3328 3334 JavaThread* thread = JavaThread::current();
3329 3335 ThreadToNativeFromVM ttn(thread);
3330 3336 HandleMark hm(thread);
3331 3337 (*unload_entry)(&main_vm);
3332 3338 break;
3333 3339 }
3334 3340 }
3335 3341 }
3336 3342 }
3337 3343
3338 3344 // Called for after the VM is initialized for -Xrun libraries which have not been converted to agent libraries
3339 3345 // Invokes JVM_OnLoad
3340 3346 void Threads::create_vm_init_libraries() {
3341 3347 extern struct JavaVM_ main_vm;
3342 3348 AgentLibrary* agent;
3343 3349
3344 3350 for (agent = Arguments::libraries(); agent != NULL; agent = agent->next()) {
3345 3351 OnLoadEntry_t on_load_entry = lookup_jvm_on_load(agent);
3346 3352
3347 3353 if (on_load_entry != NULL) {
3348 3354 // Invoke the JVM_OnLoad function
3349 3355 JavaThread* thread = JavaThread::current();
3350 3356 ThreadToNativeFromVM ttn(thread);
3351 3357 HandleMark hm(thread);
3352 3358 jint err = (*on_load_entry)(&main_vm, agent->options(), NULL);
3353 3359 if (err != JNI_OK) {
3354 3360 vm_exit_during_initialization("-Xrun library failed to init", agent->name());
3355 3361 }
3356 3362 } else {
3357 3363 vm_exit_during_initialization("Could not find JVM_OnLoad function in -Xrun library", agent->name());
3358 3364 }
3359 3365 }
3360 3366 }
3361 3367
3362 3368 // Last thread running calls java.lang.Shutdown.shutdown()
3363 3369 void JavaThread::invoke_shutdown_hooks() {
3364 3370 HandleMark hm(this);
3365 3371
3366 3372 // We could get here with a pending exception, if so clear it now.
3367 3373 if (this->has_pending_exception()) {
3368 3374 this->clear_pending_exception();
3369 3375 }
3370 3376
3371 3377 EXCEPTION_MARK;
3372 3378 klassOop k =
3373 3379 SystemDictionary::resolve_or_null(vmSymbolHandles::java_lang_Shutdown(),
3374 3380 THREAD);
3375 3381 if (k != NULL) {
3376 3382 // SystemDictionary::resolve_or_null will return null if there was
3377 3383 // an exception. If we cannot load the Shutdown class, just don't
3378 3384 // call Shutdown.shutdown() at all. This will mean the shutdown hooks
3379 3385 // and finalizers (if runFinalizersOnExit is set) won't be run.
3380 3386 // Note that if a shutdown hook was registered or runFinalizersOnExit
3381 3387 // was called, the Shutdown class would have already been loaded
3382 3388 // (Runtime.addShutdownHook and runFinalizersOnExit will load it).
3383 3389 instanceKlassHandle shutdown_klass (THREAD, k);
3384 3390 JavaValue result(T_VOID);
3385 3391 JavaCalls::call_static(&result,
3386 3392 shutdown_klass,
3387 3393 vmSymbolHandles::shutdown_method_name(),
3388 3394 vmSymbolHandles::void_method_signature(),
3389 3395 THREAD);
3390 3396 }
3391 3397 CLEAR_PENDING_EXCEPTION;
3392 3398 }
3393 3399
3394 3400 // Threads::destroy_vm() is normally called from jni_DestroyJavaVM() when
3395 3401 // the program falls off the end of main(). Another VM exit path is through
3396 3402 // vm_exit() when the program calls System.exit() to return a value or when
3397 3403 // there is a serious error in VM. The two shutdown paths are not exactly
3398 3404 // the same, but they share Shutdown.shutdown() at Java level and before_exit()
3399 3405 // and VM_Exit op at VM level.
3400 3406 //
3401 3407 // Shutdown sequence:
3402 3408 // + Wait until we are the last non-daemon thread to execute
3403 3409 // <-- every thing is still working at this moment -->
3404 3410 // + Call java.lang.Shutdown.shutdown(), which will invoke Java level
3405 3411 // shutdown hooks, run finalizers if finalization-on-exit
3406 3412 // + Call before_exit(), prepare for VM exit
3407 3413 // > run VM level shutdown hooks (they are registered through JVM_OnExit(),
3408 3414 // currently the only user of this mechanism is File.deleteOnExit())
3409 3415 // > stop flat profiler, StatSampler, watcher thread, CMS threads,
3410 3416 // post thread end and vm death events to JVMTI,
3411 3417 // stop signal thread
3412 3418 // + Call JavaThread::exit(), it will:
3413 3419 // > release JNI handle blocks, remove stack guard pages
3414 3420 // > remove this thread from Threads list
3415 3421 // <-- no more Java code from this thread after this point -->
3416 3422 // + Stop VM thread, it will bring the remaining VM to a safepoint and stop
3417 3423 // the compiler threads at safepoint
3418 3424 // <-- do not use anything that could get blocked by Safepoint -->
3419 3425 // + Disable tracing at JNI/JVM barriers
3420 3426 // + Set _vm_exited flag for threads that are still running native code
3421 3427 // + Delete this thread
3422 3428 // + Call exit_globals()
3423 3429 // > deletes tty
3424 3430 // > deletes PerfMemory resources
3425 3431 // + Return to caller
3426 3432
3427 3433 bool Threads::destroy_vm() {
3428 3434 JavaThread* thread = JavaThread::current();
3429 3435
3430 3436 // Wait until we are the last non-daemon thread to execute
3431 3437 { MutexLocker nu(Threads_lock);
3432 3438 while (Threads::number_of_non_daemon_threads() > 1 )
3433 3439 // This wait should make safepoint checks, wait without a timeout,
3434 3440 // and wait as a suspend-equivalent condition.
3435 3441 //
3436 3442 // Note: If the FlatProfiler is running and this thread is waiting
3437 3443 // for another non-daemon thread to finish, then the FlatProfiler
3438 3444 // is waiting for the external suspend request on this thread to
3439 3445 // complete. wait_for_ext_suspend_completion() will eventually
3440 3446 // timeout, but that takes time. Making this wait a suspend-
3441 3447 // equivalent condition solves that timeout problem.
3442 3448 //
3443 3449 Threads_lock->wait(!Mutex::_no_safepoint_check_flag, 0,
3444 3450 Mutex::_as_suspend_equivalent_flag);
3445 3451 }
3446 3452
3447 3453 // Hang forever on exit if we are reporting an error.
3448 3454 if (ShowMessageBoxOnError && is_error_reported()) {
3449 3455 os::infinite_sleep();
3450 3456 }
3451 3457
3452 3458 if (JDK_Version::is_jdk12x_version()) {
3453 3459 // We are the last thread running, so check if finalizers should be run.
3454 3460 // For 1.3 or later this is done in thread->invoke_shutdown_hooks()
3455 3461 HandleMark rm(thread);
3456 3462 Universe::run_finalizers_on_exit();
3457 3463 } else {
3458 3464 // run Java level shutdown hooks
3459 3465 thread->invoke_shutdown_hooks();
3460 3466 }
3461 3467
3462 3468 before_exit(thread);
3463 3469
3464 3470 thread->exit(true);
3465 3471
3466 3472 // Stop VM thread.
3467 3473 {
3468 3474 // 4945125 The vm thread comes to a safepoint during exit.
3469 3475 // GC vm_operations can get caught at the safepoint, and the
3470 3476 // heap is unparseable if they are caught. Grab the Heap_lock
3471 3477 // to prevent this. The GC vm_operations will not be able to
3472 3478 // queue until after the vm thread is dead.
3473 3479 MutexLocker ml(Heap_lock);
3474 3480
3475 3481 VMThread::wait_for_vm_thread_exit();
3476 3482 assert(SafepointSynchronize::is_at_safepoint(), "VM thread should exit at Safepoint");
3477 3483 VMThread::destroy();
3478 3484 }
3479 3485
3480 3486 // clean up ideal graph printers
3481 3487 #if defined(COMPILER2) && !defined(PRODUCT)
3482 3488 IdealGraphPrinter::clean_up();
3483 3489 #endif
3484 3490
3485 3491 // Now, all Java threads are gone except daemon threads. Daemon threads
3486 3492 // running Java code or in VM are stopped by the Safepoint. However,
3487 3493 // daemon threads executing native code are still running. But they
3488 3494 // will be stopped at native=>Java/VM barriers. Note that we can't
3489 3495 // simply kill or suspend them, as it is inherently deadlock-prone.
3490 3496
3491 3497 #ifndef PRODUCT
3492 3498 // disable function tracing at JNI/JVM barriers
3493 3499 TraceHPI = false;
3494 3500 TraceJNICalls = false;
3495 3501 TraceJVMCalls = false;
3496 3502 TraceRuntimeCalls = false;
3497 3503 #endif
3498 3504
3499 3505 VM_Exit::set_vm_exited();
3500 3506
3501 3507 notify_vm_shutdown();
3502 3508
3503 3509 delete thread;
3504 3510
3505 3511 // exit_globals() will delete tty
3506 3512 exit_globals();
3507 3513
3508 3514 return true;
3509 3515 }
3510 3516
3511 3517
3512 3518 jboolean Threads::is_supported_jni_version_including_1_1(jint version) {
3513 3519 if (version == JNI_VERSION_1_1) return JNI_TRUE;
3514 3520 return is_supported_jni_version(version);
3515 3521 }
3516 3522
3517 3523
3518 3524 jboolean Threads::is_supported_jni_version(jint version) {
3519 3525 if (version == JNI_VERSION_1_2) return JNI_TRUE;
3520 3526 if (version == JNI_VERSION_1_4) return JNI_TRUE;
3521 3527 if (version == JNI_VERSION_1_6) return JNI_TRUE;
3522 3528 return JNI_FALSE;
3523 3529 }
3524 3530
3525 3531
3526 3532 void Threads::add(JavaThread* p, bool force_daemon) {
3527 3533 // The threads lock must be owned at this point
3528 3534 assert_locked_or_safepoint(Threads_lock);
3529 3535 p->set_next(_thread_list);
3530 3536 _thread_list = p;
3531 3537 _number_of_threads++;
3532 3538 oop threadObj = p->threadObj();
3533 3539 bool daemon = true;
3534 3540 // Bootstrapping problem: threadObj can be null for initial
3535 3541 // JavaThread (or for threads attached via JNI)
3536 3542 if ((!force_daemon) && (threadObj == NULL || !java_lang_Thread::is_daemon(threadObj))) {
3537 3543 _number_of_non_daemon_threads++;
3538 3544 daemon = false;
3539 3545 }
3540 3546
3541 3547 ThreadService::add_thread(p, daemon);
3542 3548
3543 3549 // Possible GC point.
3544 3550 Events::log("Thread added: " INTPTR_FORMAT, p);
3545 3551 }
3546 3552
3547 3553 void Threads::remove(JavaThread* p) {
3548 3554 // Extra scope needed for Thread_lock, so we can check
3549 3555 // that we do not remove thread without safepoint code notice
3550 3556 { MutexLocker ml(Threads_lock);
3551 3557
3552 3558 assert(includes(p), "p must be present");
3553 3559
3554 3560 JavaThread* current = _thread_list;
3555 3561 JavaThread* prev = NULL;
3556 3562
3557 3563 while (current != p) {
3558 3564 prev = current;
3559 3565 current = current->next();
3560 3566 }
3561 3567
3562 3568 if (prev) {
3563 3569 prev->set_next(current->next());
3564 3570 } else {
3565 3571 _thread_list = p->next();
3566 3572 }
3567 3573 _number_of_threads--;
3568 3574 oop threadObj = p->threadObj();
3569 3575 bool daemon = true;
3570 3576 if (threadObj == NULL || !java_lang_Thread::is_daemon(threadObj)) {
3571 3577 _number_of_non_daemon_threads--;
3572 3578 daemon = false;
3573 3579
3574 3580 // Only one thread left, do a notify on the Threads_lock so a thread waiting
3575 3581 // on destroy_vm will wake up.
3576 3582 if (number_of_non_daemon_threads() == 1)
3577 3583 Threads_lock->notify_all();
3578 3584 }
3579 3585 ThreadService::remove_thread(p, daemon);
3580 3586
3581 3587 // Make sure that safepoint code disregard this thread. This is needed since
3582 3588 // the thread might mess around with locks after this point. This can cause it
3583 3589 // to do callbacks into the safepoint code. However, the safepoint code is not aware
3584 3590 // of this thread since it is removed from the queue.
3585 3591 p->set_terminated_value();
3586 3592 } // unlock Threads_lock
3587 3593
3588 3594 // Since Events::log uses a lock, we grab it outside the Threads_lock
3589 3595 Events::log("Thread exited: " INTPTR_FORMAT, p);
3590 3596 }
3591 3597
3592 3598 // Threads_lock must be held when this is called (or must be called during a safepoint)
3593 3599 bool Threads::includes(JavaThread* p) {
3594 3600 assert(Threads_lock->is_locked(), "sanity check");
3595 3601 ALL_JAVA_THREADS(q) {
3596 3602 if (q == p ) {
3597 3603 return true;
3598 3604 }
3599 3605 }
3600 3606 return false;
3601 3607 }
3602 3608
3603 3609 // Operations on the Threads list for GC. These are not explicitly locked,
3604 3610 // but the garbage collector must provide a safe context for them to run.
3605 3611 // In particular, these things should never be called when the Threads_lock
3606 3612 // is held by some other thread. (Note: the Safepoint abstraction also
3607 3613 // uses the Threads_lock to gurantee this property. It also makes sure that
3608 3614 // all threads gets blocked when exiting or starting).
3609 3615
3610 3616 void Threads::oops_do(OopClosure* f, CodeBlobClosure* cf) {
3611 3617 ALL_JAVA_THREADS(p) {
3612 3618 p->oops_do(f, cf);
3613 3619 }
3614 3620 VMThread::vm_thread()->oops_do(f, cf);
3615 3621 }
3616 3622
3617 3623 void Threads::possibly_parallel_oops_do(OopClosure* f, CodeBlobClosure* cf) {
3618 3624 // Introduce a mechanism allowing parallel threads to claim threads as
3619 3625 // root groups. Overhead should be small enough to use all the time,
3620 3626 // even in sequential code.
3621 3627 SharedHeap* sh = SharedHeap::heap();
3622 3628 bool is_par = (sh->n_par_threads() > 0);
3623 3629 int cp = SharedHeap::heap()->strong_roots_parity();
3624 3630 ALL_JAVA_THREADS(p) {
3625 3631 if (p->claim_oops_do(is_par, cp)) {
3626 3632 p->oops_do(f, cf);
3627 3633 }
3628 3634 }
3629 3635 VMThread* vmt = VMThread::vm_thread();
3630 3636 if (vmt->claim_oops_do(is_par, cp))
3631 3637 vmt->oops_do(f, cf);
3632 3638 }
3633 3639
3634 3640 #ifndef SERIALGC
3635 3641 // Used by ParallelScavenge
3636 3642 void Threads::create_thread_roots_tasks(GCTaskQueue* q) {
3637 3643 ALL_JAVA_THREADS(p) {
3638 3644 q->enqueue(new ThreadRootsTask(p));
3639 3645 }
3640 3646 q->enqueue(new ThreadRootsTask(VMThread::vm_thread()));
3641 3647 }
3642 3648
3643 3649 // Used by Parallel Old
3644 3650 void Threads::create_thread_roots_marking_tasks(GCTaskQueue* q) {
3645 3651 ALL_JAVA_THREADS(p) {
3646 3652 q->enqueue(new ThreadRootsMarkingTask(p));
3647 3653 }
3648 3654 q->enqueue(new ThreadRootsMarkingTask(VMThread::vm_thread()));
3649 3655 }
3650 3656 #endif // SERIALGC
3651 3657
3652 3658 void Threads::nmethods_do(CodeBlobClosure* cf) {
3653 3659 ALL_JAVA_THREADS(p) {
3654 3660 p->nmethods_do(cf);
3655 3661 }
3656 3662 VMThread::vm_thread()->nmethods_do(cf);
3657 3663 }
3658 3664
3659 3665 void Threads::gc_epilogue() {
3660 3666 ALL_JAVA_THREADS(p) {
3661 3667 p->gc_epilogue();
3662 3668 }
3663 3669 }
3664 3670
3665 3671 void Threads::gc_prologue() {
3666 3672 ALL_JAVA_THREADS(p) {
3667 3673 p->gc_prologue();
3668 3674 }
3669 3675 }
3670 3676
3671 3677 void Threads::deoptimized_wrt_marked_nmethods() {
3672 3678 ALL_JAVA_THREADS(p) {
3673 3679 p->deoptimized_wrt_marked_nmethods();
3674 3680 }
3675 3681 }
3676 3682
3677 3683
3678 3684 // Get count Java threads that are waiting to enter the specified monitor.
3679 3685 GrowableArray<JavaThread*>* Threads::get_pending_threads(int count,
3680 3686 address monitor, bool doLock) {
3681 3687 assert(doLock || SafepointSynchronize::is_at_safepoint(),
3682 3688 "must grab Threads_lock or be at safepoint");
3683 3689 GrowableArray<JavaThread*>* result = new GrowableArray<JavaThread*>(count);
3684 3690
3685 3691 int i = 0;
3686 3692 {
3687 3693 MutexLockerEx ml(doLock ? Threads_lock : NULL);
3688 3694 ALL_JAVA_THREADS(p) {
3689 3695 if (p->is_Compiler_thread()) continue;
3690 3696
3691 3697 address pending = (address)p->current_pending_monitor();
3692 3698 if (pending == monitor) { // found a match
3693 3699 if (i < count) result->append(p); // save the first count matches
3694 3700 i++;
3695 3701 }
3696 3702 }
3697 3703 }
3698 3704 return result;
3699 3705 }
3700 3706
3701 3707
3702 3708 JavaThread *Threads::owning_thread_from_monitor_owner(address owner, bool doLock) {
3703 3709 assert(doLock ||
3704 3710 Threads_lock->owned_by_self() ||
3705 3711 SafepointSynchronize::is_at_safepoint(),
3706 3712 "must grab Threads_lock or be at safepoint");
3707 3713
3708 3714 // NULL owner means not locked so we can skip the search
3709 3715 if (owner == NULL) return NULL;
3710 3716
3711 3717 {
3712 3718 MutexLockerEx ml(doLock ? Threads_lock : NULL);
3713 3719 ALL_JAVA_THREADS(p) {
3714 3720 // first, see if owner is the address of a Java thread
3715 3721 if (owner == (address)p) return p;
3716 3722 }
3717 3723 }
3718 3724 assert(UseHeavyMonitors == false, "Did not find owning Java thread with UseHeavyMonitors enabled");
3719 3725 if (UseHeavyMonitors) return NULL;
3720 3726
3721 3727 //
3722 3728 // If we didn't find a matching Java thread and we didn't force use of
3723 3729 // heavyweight monitors, then the owner is the stack address of the
3724 3730 // Lock Word in the owning Java thread's stack.
3725 3731 //
3726 3732 JavaThread* the_owner = NULL;
3727 3733 {
3728 3734 MutexLockerEx ml(doLock ? Threads_lock : NULL);
3729 3735 ALL_JAVA_THREADS(q) {
3730 3736 if (q->is_lock_owned(owner)) {
3731 3737 the_owner = q;
3732 3738 break;
3733 3739 }
3734 3740 }
3735 3741 }
3736 3742 assert(the_owner != NULL, "Did not find owning Java thread for lock word address");
3737 3743 return the_owner;
3738 3744 }
3739 3745
3740 3746 // Threads::print_on() is called at safepoint by VM_PrintThreads operation.
3741 3747 void Threads::print_on(outputStream* st, bool print_stacks, bool internal_format, bool print_concurrent_locks) {
3742 3748 char buf[32];
3743 3749 st->print_cr(os::local_time_string(buf, sizeof(buf)));
3744 3750
3745 3751 st->print_cr("Full thread dump %s (%s %s):",
3746 3752 Abstract_VM_Version::vm_name(),
3747 3753 Abstract_VM_Version::vm_release(),
3748 3754 Abstract_VM_Version::vm_info_string()
3749 3755 );
3750 3756 st->cr();
3751 3757
3752 3758 #ifndef SERIALGC
3753 3759 // Dump concurrent locks
3754 3760 ConcurrentLocksDump concurrent_locks;
3755 3761 if (print_concurrent_locks) {
3756 3762 concurrent_locks.dump_at_safepoint();
3757 3763 }
3758 3764 #endif // SERIALGC
3759 3765
3760 3766 ALL_JAVA_THREADS(p) {
3761 3767 ResourceMark rm;
3762 3768 p->print_on(st);
3763 3769 if (print_stacks) {
3764 3770 if (internal_format) {
3765 3771 p->trace_stack();
3766 3772 } else {
3767 3773 p->print_stack_on(st);
3768 3774 }
3769 3775 }
3770 3776 st->cr();
3771 3777 #ifndef SERIALGC
3772 3778 if (print_concurrent_locks) {
3773 3779 concurrent_locks.print_locks_on(p, st);
3774 3780 }
3775 3781 #endif // SERIALGC
3776 3782 }
3777 3783
3778 3784 VMThread::vm_thread()->print_on(st);
3779 3785 st->cr();
3780 3786 Universe::heap()->print_gc_threads_on(st);
3781 3787 WatcherThread* wt = WatcherThread::watcher_thread();
3782 3788 if (wt != NULL) wt->print_on(st);
3783 3789 st->cr();
3784 3790 CompileBroker::print_compiler_threads_on(st);
3785 3791 st->flush();
3786 3792 }
3787 3793
3788 3794 // Threads::print_on_error() is called by fatal error handler. It's possible
3789 3795 // that VM is not at safepoint and/or current thread is inside signal handler.
3790 3796 // Don't print stack trace, as the stack may not be walkable. Don't allocate
3791 3797 // memory (even in resource area), it might deadlock the error handler.
3792 3798 void Threads::print_on_error(outputStream* st, Thread* current, char* buf, int buflen) {
3793 3799 bool found_current = false;
3794 3800 st->print_cr("Java Threads: ( => current thread )");
3795 3801 ALL_JAVA_THREADS(thread) {
3796 3802 bool is_current = (current == thread);
3797 3803 found_current = found_current || is_current;
3798 3804
3799 3805 st->print("%s", is_current ? "=>" : " ");
3800 3806
3801 3807 st->print(PTR_FORMAT, thread);
3802 3808 st->print(" ");
3803 3809 thread->print_on_error(st, buf, buflen);
3804 3810 st->cr();
3805 3811 }
3806 3812 st->cr();
3807 3813
3808 3814 st->print_cr("Other Threads:");
3809 3815 if (VMThread::vm_thread()) {
3810 3816 bool is_current = (current == VMThread::vm_thread());
3811 3817 found_current = found_current || is_current;
3812 3818 st->print("%s", current == VMThread::vm_thread() ? "=>" : " ");
3813 3819
3814 3820 st->print(PTR_FORMAT, VMThread::vm_thread());
3815 3821 st->print(" ");
3816 3822 VMThread::vm_thread()->print_on_error(st, buf, buflen);
3817 3823 st->cr();
3818 3824 }
3819 3825 WatcherThread* wt = WatcherThread::watcher_thread();
3820 3826 if (wt != NULL) {
3821 3827 bool is_current = (current == wt);
3822 3828 found_current = found_current || is_current;
3823 3829 st->print("%s", is_current ? "=>" : " ");
3824 3830
3825 3831 st->print(PTR_FORMAT, wt);
3826 3832 st->print(" ");
3827 3833 wt->print_on_error(st, buf, buflen);
3828 3834 st->cr();
3829 3835 }
3830 3836 if (!found_current) {
3831 3837 st->cr();
3832 3838 st->print("=>" PTR_FORMAT " (exited) ", current);
3833 3839 current->print_on_error(st, buf, buflen);
3834 3840 st->cr();
3835 3841 }
3836 3842 }
3837 3843
3838 3844
3839 3845 // Lifecycle management for TSM ParkEvents.
3840 3846 // ParkEvents are type-stable (TSM).
3841 3847 // In our particular implementation they happen to be immortal.
3842 3848 //
3843 3849 // We manage concurrency on the FreeList with a CAS-based
3844 3850 // detach-modify-reattach idiom that avoids the ABA problems
3845 3851 // that would otherwise be present in a simple CAS-based
3846 3852 // push-pop implementation. (push-one and pop-all)
3847 3853 //
3848 3854 // Caveat: Allocate() and Release() may be called from threads
3849 3855 // other than the thread associated with the Event!
3850 3856 // If we need to call Allocate() when running as the thread in
3851 3857 // question then look for the PD calls to initialize native TLS.
3852 3858 // Native TLS (Win32/Linux/Solaris) can only be initialized or
3853 3859 // accessed by the associated thread.
3854 3860 // See also pd_initialize().
3855 3861 //
3856 3862 // Note that we could defer associating a ParkEvent with a thread
3857 3863 // until the 1st time the thread calls park(). unpark() calls to
3858 3864 // an unprovisioned thread would be ignored. The first park() call
3859 3865 // for a thread would allocate and associate a ParkEvent and return
3860 3866 // immediately.
3861 3867
3862 3868 volatile int ParkEvent::ListLock = 0 ;
3863 3869 ParkEvent * volatile ParkEvent::FreeList = NULL ;
3864 3870
3865 3871 ParkEvent * ParkEvent::Allocate (Thread * t) {
3866 3872 // In rare cases -- JVM_RawMonitor* operations -- we can find t == null.
3867 3873 ParkEvent * ev ;
3868 3874
3869 3875 // Start by trying to recycle an existing but unassociated
3870 3876 // ParkEvent from the global free list.
3871 3877 for (;;) {
3872 3878 ev = FreeList ;
3873 3879 if (ev == NULL) break ;
3874 3880 // 1: Detach - sequester or privatize the list
3875 3881 // Tantamount to ev = Swap (&FreeList, NULL)
3876 3882 if (Atomic::cmpxchg_ptr (NULL, &FreeList, ev) != ev) {
3877 3883 continue ;
3878 3884 }
3879 3885
3880 3886 // We've detached the list. The list in-hand is now
3881 3887 // local to this thread. This thread can operate on the
3882 3888 // list without risk of interference from other threads.
3883 3889 // 2: Extract -- pop the 1st element from the list.
3884 3890 ParkEvent * List = ev->FreeNext ;
3885 3891 if (List == NULL) break ;
3886 3892 for (;;) {
3887 3893 // 3: Try to reattach the residual list
3888 3894 guarantee (List != NULL, "invariant") ;
3889 3895 ParkEvent * Arv = (ParkEvent *) Atomic::cmpxchg_ptr (List, &FreeList, NULL) ;
3890 3896 if (Arv == NULL) break ;
3891 3897
3892 3898 // New nodes arrived. Try to detach the recent arrivals.
3893 3899 if (Atomic::cmpxchg_ptr (NULL, &FreeList, Arv) != Arv) {
3894 3900 continue ;
3895 3901 }
3896 3902 guarantee (Arv != NULL, "invariant") ;
3897 3903 // 4: Merge Arv into List
3898 3904 ParkEvent * Tail = List ;
3899 3905 while (Tail->FreeNext != NULL) Tail = Tail->FreeNext ;
3900 3906 Tail->FreeNext = Arv ;
3901 3907 }
3902 3908 break ;
3903 3909 }
3904 3910
3905 3911 if (ev != NULL) {
3906 3912 guarantee (ev->AssociatedWith == NULL, "invariant") ;
3907 3913 } else {
3908 3914 // Do this the hard way -- materialize a new ParkEvent.
3909 3915 // In rare cases an allocating thread might detach a long list --
3910 3916 // installing null into FreeList -- and then stall or be obstructed.
3911 3917 // A 2nd thread calling Allocate() would see FreeList == null.
3912 3918 // The list held privately by the 1st thread is unavailable to the 2nd thread.
3913 3919 // In that case the 2nd thread would have to materialize a new ParkEvent,
3914 3920 // even though free ParkEvents existed in the system. In this case we end up
3915 3921 // with more ParkEvents in circulation than we need, but the race is
3916 3922 // rare and the outcome is benign. Ideally, the # of extant ParkEvents
3917 3923 // is equal to the maximum # of threads that existed at any one time.
3918 3924 // Because of the race mentioned above, segments of the freelist
3919 3925 // can be transiently inaccessible. At worst we may end up with the
3920 3926 // # of ParkEvents in circulation slightly above the ideal.
3921 3927 // Note that if we didn't have the TSM/immortal constraint, then
3922 3928 // when reattaching, above, we could trim the list.
3923 3929 ev = new ParkEvent () ;
3924 3930 guarantee ((intptr_t(ev) & 0xFF) == 0, "invariant") ;
3925 3931 }
3926 3932 ev->reset() ; // courtesy to caller
3927 3933 ev->AssociatedWith = t ; // Associate ev with t
3928 3934 ev->FreeNext = NULL ;
3929 3935 return ev ;
3930 3936 }
3931 3937
3932 3938 void ParkEvent::Release (ParkEvent * ev) {
3933 3939 if (ev == NULL) return ;
3934 3940 guarantee (ev->FreeNext == NULL , "invariant") ;
3935 3941 ev->AssociatedWith = NULL ;
3936 3942 for (;;) {
3937 3943 // Push ev onto FreeList
3938 3944 // The mechanism is "half" lock-free.
3939 3945 ParkEvent * List = FreeList ;
3940 3946 ev->FreeNext = List ;
3941 3947 if (Atomic::cmpxchg_ptr (ev, &FreeList, List) == List) break ;
3942 3948 }
3943 3949 }
3944 3950
3945 3951 // Override operator new and delete so we can ensure that the
3946 3952 // least significant byte of ParkEvent addresses is 0.
3947 3953 // Beware that excessive address alignment is undesirable
3948 3954 // as it can result in D$ index usage imbalance as
3949 3955 // well as bank access imbalance on Niagara-like platforms,
3950 3956 // although Niagara's hash function should help.
3951 3957
3952 3958 void * ParkEvent::operator new (size_t sz) {
3953 3959 return (void *) ((intptr_t (CHeapObj::operator new (sz + 256)) + 256) & -256) ;
3954 3960 }
3955 3961
3956 3962 void ParkEvent::operator delete (void * a) {
3957 3963 // ParkEvents are type-stable and immortal ...
3958 3964 ShouldNotReachHere();
3959 3965 }
3960 3966
3961 3967
3962 3968 // 6399321 As a temporary measure we copied & modified the ParkEvent::
3963 3969 // allocate() and release() code for use by Parkers. The Parker:: forms
3964 3970 // will eventually be removed as we consolide and shift over to ParkEvents
3965 3971 // for both builtin synchronization and JSR166 operations.
3966 3972
3967 3973 volatile int Parker::ListLock = 0 ;
3968 3974 Parker * volatile Parker::FreeList = NULL ;
3969 3975
3970 3976 Parker * Parker::Allocate (JavaThread * t) {
3971 3977 guarantee (t != NULL, "invariant") ;
3972 3978 Parker * p ;
3973 3979
3974 3980 // Start by trying to recycle an existing but unassociated
3975 3981 // Parker from the global free list.
3976 3982 for (;;) {
3977 3983 p = FreeList ;
3978 3984 if (p == NULL) break ;
3979 3985 // 1: Detach
3980 3986 // Tantamount to p = Swap (&FreeList, NULL)
3981 3987 if (Atomic::cmpxchg_ptr (NULL, &FreeList, p) != p) {
3982 3988 continue ;
3983 3989 }
3984 3990
3985 3991 // We've detached the list. The list in-hand is now
3986 3992 // local to this thread. This thread can operate on the
3987 3993 // list without risk of interference from other threads.
3988 3994 // 2: Extract -- pop the 1st element from the list.
3989 3995 Parker * List = p->FreeNext ;
3990 3996 if (List == NULL) break ;
3991 3997 for (;;) {
3992 3998 // 3: Try to reattach the residual list
3993 3999 guarantee (List != NULL, "invariant") ;
3994 4000 Parker * Arv = (Parker *) Atomic::cmpxchg_ptr (List, &FreeList, NULL) ;
3995 4001 if (Arv == NULL) break ;
3996 4002
3997 4003 // New nodes arrived. Try to detach the recent arrivals.
3998 4004 if (Atomic::cmpxchg_ptr (NULL, &FreeList, Arv) != Arv) {
3999 4005 continue ;
4000 4006 }
4001 4007 guarantee (Arv != NULL, "invariant") ;
4002 4008 // 4: Merge Arv into List
4003 4009 Parker * Tail = List ;
4004 4010 while (Tail->FreeNext != NULL) Tail = Tail->FreeNext ;
4005 4011 Tail->FreeNext = Arv ;
4006 4012 }
4007 4013 break ;
4008 4014 }
4009 4015
4010 4016 if (p != NULL) {
4011 4017 guarantee (p->AssociatedWith == NULL, "invariant") ;
4012 4018 } else {
4013 4019 // Do this the hard way -- materialize a new Parker..
4014 4020 // In rare cases an allocating thread might detach
4015 4021 // a long list -- installing null into FreeList --and
4016 4022 // then stall. Another thread calling Allocate() would see
4017 4023 // FreeList == null and then invoke the ctor. In this case we
4018 4024 // end up with more Parkers in circulation than we need, but
4019 4025 // the race is rare and the outcome is benign.
4020 4026 // Ideally, the # of extant Parkers is equal to the
4021 4027 // maximum # of threads that existed at any one time.
4022 4028 // Because of the race mentioned above, segments of the
4023 4029 // freelist can be transiently inaccessible. At worst
4024 4030 // we may end up with the # of Parkers in circulation
4025 4031 // slightly above the ideal.
4026 4032 p = new Parker() ;
4027 4033 }
4028 4034 p->AssociatedWith = t ; // Associate p with t
4029 4035 p->FreeNext = NULL ;
4030 4036 return p ;
4031 4037 }
4032 4038
4033 4039
4034 4040 void Parker::Release (Parker * p) {
4035 4041 if (p == NULL) return ;
4036 4042 guarantee (p->AssociatedWith != NULL, "invariant") ;
4037 4043 guarantee (p->FreeNext == NULL , "invariant") ;
4038 4044 p->AssociatedWith = NULL ;
4039 4045 for (;;) {
4040 4046 // Push p onto FreeList
4041 4047 Parker * List = FreeList ;
4042 4048 p->FreeNext = List ;
4043 4049 if (Atomic::cmpxchg_ptr (p, &FreeList, List) == List) break ;
4044 4050 }
4045 4051 }
4046 4052
4047 4053 void Threads::verify() {
4048 4054 ALL_JAVA_THREADS(p) {
4049 4055 p->verify();
4050 4056 }
4051 4057 VMThread* thread = VMThread::vm_thread();
4052 4058 if (thread != NULL) thread->verify();
4053 4059 }
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