1 /* 2 * Copyright 1997-2007 Sun Microsystems, Inc. All Rights Reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25 # include "incls/_precompiled.incl" 26 # include "incls/_vm_operations.cpp.incl" 27 28 #define VM_OP_NAME_INITIALIZE(name) #name, 29 30 const char* VM_Operation::_names[VM_Operation::VMOp_Terminating] = \ 31 { VM_OPS_DO(VM_OP_NAME_INITIALIZE) }; 32 33 void VM_Operation::set_calling_thread(Thread* thread, ThreadPriority priority) { 34 _calling_thread = thread; 35 assert(MinPriority <= priority && priority <= MaxPriority, "sanity check"); 36 _priority = priority; 37 } 38 39 40 void VM_Operation::evaluate() { 41 ResourceMark rm; 42 if (TraceVMOperation) { 43 tty->print("["); 44 NOT_PRODUCT(print();) 45 } 46 doit(); 47 if (TraceVMOperation) { 48 tty->print_cr("]"); 49 } 50 } 51 52 // Called by fatal error handler. 53 void VM_Operation::print_on_error(outputStream* st) const { 54 st->print("VM_Operation (" PTR_FORMAT "): ", this); 55 st->print("%s", name()); 56 57 const char* mode; 58 switch(evaluation_mode()) { 59 case _safepoint : mode = "safepoint"; break; 60 case _no_safepoint : mode = "no safepoint"; break; 61 case _concurrent : mode = "concurrent"; break; 62 case _async_safepoint: mode = "async safepoint"; break; 63 default : mode = "unknown"; break; 64 } 65 st->print(", mode: %s", mode); 66 67 if (calling_thread()) { 68 st->print(", requested by thread " PTR_FORMAT, calling_thread()); 69 } 70 } 71 72 void VM_ThreadStop::doit() { 73 assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint"); 74 JavaThread* target = java_lang_Thread::thread(target_thread()); 75 // Note that this now allows multiple ThreadDeath exceptions to be 76 // thrown at a thread. 77 if (target != NULL) { 78 // the thread has run and is not already in the process of exiting 79 target->send_thread_stop(throwable()); 80 } 81 } 82 83 void VM_Deoptimize::doit() { 84 // We do not want any GCs to happen while we are in the middle of this VM operation 85 ResourceMark rm; 86 DeoptimizationMarker dm; 87 88 // Deoptimize all activations depending on marked nmethods 89 Deoptimization::deoptimize_dependents(); 90 91 // Make the dependent methods zombies 92 CodeCache::make_marked_nmethods_zombies(); 93 } 94 95 96 VM_DeoptimizeFrame::VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id) { 97 _thread = thread; 98 _id = id; 99 } 100 101 102 void VM_DeoptimizeFrame::doit() { 103 Deoptimization::deoptimize_frame(_thread, _id); 104 } 105 106 107 #ifndef PRODUCT 108 109 void VM_DeoptimizeAll::doit() { 110 DeoptimizationMarker dm; 111 // deoptimize all java threads in the system 112 if (DeoptimizeALot) { 113 for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) { 114 if (thread->has_last_Java_frame()) { 115 thread->deoptimize(); 116 } 117 } 118 } else if (DeoptimizeRandom) { 119 120 // Deoptimize some selected threads and frames 121 int tnum = os::random() & 0x3; 122 int fnum = os::random() & 0x3; 123 int tcount = 0; 124 for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) { 125 if (thread->has_last_Java_frame()) { 126 if (tcount++ == tnum) { 127 tcount = 0; 128 int fcount = 0; 129 // Deoptimize some selected frames. 130 // Biased llocking wants a updated register map 131 for(StackFrameStream fst(thread, UseBiasedLocking); !fst.is_done(); fst.next()) { 132 if (fst.current()->can_be_deoptimized()) { 133 if (fcount++ == fnum) { 134 fcount = 0; 135 Deoptimization::deoptimize(thread, *fst.current(), fst.register_map()); 136 } 137 } 138 } 139 } 140 } 141 } 142 } 143 } 144 145 146 void VM_ZombieAll::doit() { 147 JavaThread *thread = (JavaThread *)calling_thread(); 148 assert(thread->is_Java_thread(), "must be a Java thread"); 149 thread->make_zombies(); 150 } 151 152 #endif // !PRODUCT 153 154 void VM_Verify::doit() { 155 Universe::verify(); 156 } 157 158 bool VM_PrintThreads::doit_prologue() { 159 assert(Thread::current()->is_Java_thread(), "just checking"); 160 161 // Make sure AbstractOwnableSynchronizer is loaded 162 if (JDK_Version::is_gte_jdk16x_version()) { 163 java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current()); 164 } 165 166 // Get Heap_lock if concurrent locks will be dumped 167 if (_print_concurrent_locks) { 168 Heap_lock->lock(); 169 } 170 return true; 171 } 172 173 void VM_PrintThreads::doit() { 174 Threads::print_on(_out, true, false, _print_concurrent_locks); 175 } 176 177 void VM_PrintThreads::doit_epilogue() { 178 if (_print_concurrent_locks) { 179 // Release Heap_lock 180 Heap_lock->unlock(); 181 } 182 } 183 184 void VM_PrintJNI::doit() { 185 JNIHandles::print_on(_out); 186 } 187 188 VM_FindDeadlocks::~VM_FindDeadlocks() { 189 if (_deadlocks != NULL) { 190 DeadlockCycle* cycle = _deadlocks; 191 while (cycle != NULL) { 192 DeadlockCycle* d = cycle; 193 cycle = cycle->next(); 194 delete d; 195 } 196 } 197 } 198 199 bool VM_FindDeadlocks::doit_prologue() { 200 assert(Thread::current()->is_Java_thread(), "just checking"); 201 202 // Load AbstractOwnableSynchronizer class 203 if (_concurrent_locks && JDK_Version::is_gte_jdk16x_version()) { 204 java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current()); 205 } 206 207 return true; 208 } 209 210 void VM_FindDeadlocks::doit() { 211 _deadlocks = ThreadService::find_deadlocks_at_safepoint(_concurrent_locks); 212 if (_out != NULL) { 213 int num_deadlocks = 0; 214 for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) { 215 num_deadlocks++; 216 cycle->print_on(_out); 217 } 218 219 if (num_deadlocks == 1) { 220 _out->print_cr("\nFound 1 deadlock.\n"); 221 _out->flush(); 222 } else if (num_deadlocks > 1) { 223 _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks); 224 _out->flush(); 225 } 226 } 227 } 228 229 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result, 230 int max_depth, 231 bool with_locked_monitors, 232 bool with_locked_synchronizers) { 233 _result = result; 234 _num_threads = 0; // 0 indicates all threads 235 _threads = NULL; 236 _result = result; 237 _max_depth = max_depth; 238 _with_locked_monitors = with_locked_monitors; 239 _with_locked_synchronizers = with_locked_synchronizers; 240 } 241 242 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result, 243 GrowableArray<instanceHandle>* threads, 244 int num_threads, 245 int max_depth, 246 bool with_locked_monitors, 247 bool with_locked_synchronizers) { 248 _result = result; 249 _num_threads = num_threads; 250 _threads = threads; 251 _result = result; 252 _max_depth = max_depth; 253 _with_locked_monitors = with_locked_monitors; 254 _with_locked_synchronizers = with_locked_synchronizers; 255 } 256 257 bool VM_ThreadDump::doit_prologue() { 258 assert(Thread::current()->is_Java_thread(), "just checking"); 259 260 // Load AbstractOwnableSynchronizer class before taking thread snapshots 261 if (JDK_Version::is_gte_jdk16x_version()) { 262 java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current()); 263 } 264 265 if (_with_locked_synchronizers) { 266 // Acquire Heap_lock to dump concurrent locks 267 Heap_lock->lock(); 268 } 269 270 return true; 271 } 272 273 void VM_ThreadDump::doit_epilogue() { 274 if (_with_locked_synchronizers) { 275 // Release Heap_lock 276 Heap_lock->unlock(); 277 } 278 } 279 280 void VM_ThreadDump::doit() { 281 ResourceMark rm; 282 283 ConcurrentLocksDump concurrent_locks(true); 284 if (_with_locked_synchronizers) { 285 concurrent_locks.dump_at_safepoint(); 286 } 287 288 if (_num_threads == 0) { 289 // Snapshot all live threads 290 for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) { 291 if (jt->is_exiting() || 292 jt->is_hidden_from_external_view()) { 293 // skip terminating threads and hidden threads 294 continue; 295 } 296 ThreadConcurrentLocks* tcl = NULL; 297 if (_with_locked_synchronizers) { 298 tcl = concurrent_locks.thread_concurrent_locks(jt); 299 } 300 ThreadSnapshot* ts = snapshot_thread(jt, tcl); 301 _result->add_thread_snapshot(ts); 302 } 303 } else { 304 // Snapshot threads in the given _threads array 305 // A dummy snapshot is created if a thread doesn't exist 306 for (int i = 0; i < _num_threads; i++) { 307 instanceHandle th = _threads->at(i); 308 if (th() == NULL) { 309 // skip if the thread doesn't exist 310 // Add a dummy snapshot 311 _result->add_thread_snapshot(new ThreadSnapshot()); 312 continue; 313 } 314 315 // Dump thread stack only if the thread is alive and not exiting 316 // and not VM internal thread. 317 JavaThread* jt = java_lang_Thread::thread(th()); 318 if (jt == NULL || /* thread not alive */ 319 jt->is_exiting() || 320 jt->is_hidden_from_external_view()) { 321 // add a NULL snapshot if skipped 322 _result->add_thread_snapshot(new ThreadSnapshot()); 323 continue; 324 } 325 ThreadConcurrentLocks* tcl = NULL; 326 if (_with_locked_synchronizers) { 327 tcl = concurrent_locks.thread_concurrent_locks(jt); 328 } 329 ThreadSnapshot* ts = snapshot_thread(jt, tcl); 330 _result->add_thread_snapshot(ts); 331 } 332 } 333 } 334 335 ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) { 336 ThreadSnapshot* snapshot = new ThreadSnapshot(java_thread); 337 snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors); 338 snapshot->set_concurrent_locks(tcl); 339 return snapshot; 340 } 341 342 volatile bool VM_Exit::_vm_exited = false; 343 Thread * VM_Exit::_shutdown_thread = NULL; 344 345 int VM_Exit::set_vm_exited() { 346 Thread * thr_cur = ThreadLocalStorage::get_thread_slow(); 347 348 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already"); 349 350 int num_active = 0; 351 352 _shutdown_thread = thr_cur; 353 _vm_exited = true; // global flag 354 for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) 355 if (thr!=thr_cur && thr->thread_state() == _thread_in_native) { 356 ++num_active; 357 thr->set_terminated(JavaThread::_vm_exited); // per-thread flag 358 } 359 360 return num_active; 361 } 362 363 int VM_Exit::wait_for_threads_in_native_to_block() { 364 // VM exits at safepoint. This function must be called at the final safepoint 365 // to wait for threads in _thread_in_native state to be quiescent. 366 assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already"); 367 368 Thread * thr_cur = ThreadLocalStorage::get_thread_slow(); 369 Monitor timer(Mutex::leaf, "VM_Exit timer", true); 370 371 // Compiler threads need longer wait because they can access VM data directly 372 // while in native. If they are active and some structures being used are 373 // deleted by the shutdown sequence, they will crash. On the other hand, user 374 // threads must go through native=>Java/VM transitions first to access VM 375 // data, and they will be stopped during state transition. In theory, we 376 // don't have to wait for user threads to be quiescent, but it's always 377 // better to terminate VM when current thread is the only active thread, so 378 // wait for user threads too. Numbers are in 10 milliseconds. 379 int max_wait_user_thread = 30; // at least 300 milliseconds 380 int max_wait_compiler_thread = 1000; // at least 10 seconds 381 382 int max_wait = max_wait_compiler_thread; 383 384 int attempts = 0; 385 while (true) { 386 int num_active = 0; 387 int num_active_compiler_thread = 0; 388 389 for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) { 390 if (thr!=thr_cur && thr->thread_state() == _thread_in_native) { 391 num_active++; 392 if (thr->is_Compiler_thread()) { 393 num_active_compiler_thread++; 394 } 395 } 396 } 397 398 if (num_active == 0) { 399 return 0; 400 } else if (attempts > max_wait) { 401 return num_active; 402 } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) { 403 return num_active; 404 } 405 406 attempts++; 407 408 MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag); 409 timer.wait(Mutex::_no_safepoint_check_flag, 10); 410 } 411 } 412 413 void VM_Exit::doit() { 414 CompileBroker::set_should_block(); 415 416 // Wait for a short period for threads in native to block. Any thread 417 // still executing native code after the wait will be stopped at 418 // native==>Java/VM barriers. 419 // Among 16276 JCK tests, 94% of them come here without any threads still 420 // running in native; the other 6% are quiescent within 250ms (Ultra 80). 421 wait_for_threads_in_native_to_block(); 422 423 set_vm_exited(); 424 425 // cleanup globals resources before exiting. exit_globals() currently 426 // cleans up outputStream resources and PerfMemory resources. 427 exit_globals(); 428 429 // Check for exit hook 430 exit_hook_t exit_hook = Arguments::exit_hook(); 431 if (exit_hook != NULL) { 432 // exit hook should exit. 433 exit_hook(_exit_code); 434 // ... but if it didn't, we must do it here 435 vm_direct_exit(_exit_code); 436 } else { 437 vm_direct_exit(_exit_code); 438 } 439 } 440 441 442 void VM_Exit::wait_if_vm_exited() { 443 if (_vm_exited && 444 ThreadLocalStorage::get_thread_slow() != _shutdown_thread) { 445 // _vm_exited is set at safepoint, and the Threads_lock is never released 446 // we will block here until the process dies 447 Threads_lock->lock_without_safepoint_check(); 448 ShouldNotReachHere(); 449 } 450 }