vm_operations.cpp 13.9 KB
Newer Older
D
duke 已提交
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153
/*
 * Copyright 1997-2007 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

# include "incls/_precompiled.incl"
# include "incls/_vm_operations.cpp.incl"

#define VM_OP_NAME_INITIALIZE(name) #name,

const char* VM_Operation::_names[VM_Operation::VMOp_Terminating] = \
  { VM_OPS_DO(VM_OP_NAME_INITIALIZE) };

void VM_Operation::set_calling_thread(Thread* thread, ThreadPriority priority) {
  _calling_thread = thread;
  assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
  _priority = priority;
}


void VM_Operation::evaluate() {
  ResourceMark rm;
  if (TraceVMOperation) {
    tty->print("[");
    NOT_PRODUCT(print();)
  }
  doit();
  if (TraceVMOperation) {
    tty->print_cr("]");
  }
}

// Called by fatal error handler.
void VM_Operation::print_on_error(outputStream* st) const {
  st->print("VM_Operation (" PTR_FORMAT "): ", this);
  st->print("%s", name());

  const char* mode;
  switch(evaluation_mode()) {
    case _safepoint      : mode = "safepoint";       break;
    case _no_safepoint   : mode = "no safepoint";    break;
    case _concurrent     : mode = "concurrent";      break;
    case _async_safepoint: mode = "async safepoint"; break;
    default              : mode = "unknown";         break;
  }
  st->print(", mode: %s", mode);

  if (calling_thread()) {
    st->print(", requested by thread " PTR_FORMAT, calling_thread());
  }
}

void VM_ThreadStop::doit() {
  assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
  JavaThread* target = java_lang_Thread::thread(target_thread());
  // Note that this now allows multiple ThreadDeath exceptions to be
  // thrown at a thread.
  if (target != NULL) {
    // the thread has run and is not already in the process of exiting
    target->send_thread_stop(throwable());
  }
}

void VM_Deoptimize::doit() {
  // We do not want any GCs to happen while we are in the middle of this VM operation
  ResourceMark rm;
  DeoptimizationMarker dm;

  // Deoptimize all activations depending on marked nmethods
  Deoptimization::deoptimize_dependents();

  // Make the dependent methods zombies
  CodeCache::make_marked_nmethods_zombies();
}


VM_DeoptimizeFrame::VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id) {
  _thread = thread;
  _id     = id;
}


void VM_DeoptimizeFrame::doit() {
  Deoptimization::deoptimize_frame(_thread, _id);
}


#ifndef PRODUCT

void VM_DeoptimizeAll::doit() {
  DeoptimizationMarker dm;
  // deoptimize all java threads in the system
  if (DeoptimizeALot) {
    for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
      if (thread->has_last_Java_frame()) {
        thread->deoptimize();
      }
    }
  } else if (DeoptimizeRandom) {

    // Deoptimize some selected threads and frames
    int tnum = os::random() & 0x3;
    int fnum =  os::random() & 0x3;
    int tcount = 0;
    for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
      if (thread->has_last_Java_frame()) {
        if (tcount++ == tnum)  {
        tcount = 0;
          int fcount = 0;
          // Deoptimize some selected frames.
          // Biased llocking wants a updated register map
          for(StackFrameStream fst(thread, UseBiasedLocking); !fst.is_done(); fst.next()) {
            if (fst.current()->can_be_deoptimized()) {
              if (fcount++ == fnum) {
                fcount = 0;
                Deoptimization::deoptimize(thread, *fst.current(), fst.register_map());
              }
            }
          }
        }
      }
    }
  }
}


void VM_ZombieAll::doit() {
  JavaThread *thread = (JavaThread *)calling_thread();
  assert(thread->is_Java_thread(), "must be a Java thread");
  thread->make_zombies();
}

#endif // !PRODUCT

154 155 156 157
void VM_HandleFullCodeCache::doit() {
  NMethodSweeper::speculative_disconnect_nmethods(_is_full);
}

D
duke 已提交
158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454
void VM_Verify::doit() {
  Universe::verify();
}

bool VM_PrintThreads::doit_prologue() {
  assert(Thread::current()->is_Java_thread(), "just checking");

  // Make sure AbstractOwnableSynchronizer is loaded
  if (JDK_Version::is_gte_jdk16x_version()) {
    java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
  }

  // Get Heap_lock if concurrent locks will be dumped
  if (_print_concurrent_locks) {
    Heap_lock->lock();
  }
  return true;
}

void VM_PrintThreads::doit() {
  Threads::print_on(_out, true, false, _print_concurrent_locks);
}

void VM_PrintThreads::doit_epilogue() {
  if (_print_concurrent_locks) {
    // Release Heap_lock
    Heap_lock->unlock();
  }
}

void VM_PrintJNI::doit() {
  JNIHandles::print_on(_out);
}

VM_FindDeadlocks::~VM_FindDeadlocks() {
  if (_deadlocks != NULL) {
    DeadlockCycle* cycle = _deadlocks;
    while (cycle != NULL) {
      DeadlockCycle* d = cycle;
      cycle = cycle->next();
      delete d;
    }
  }
}

bool VM_FindDeadlocks::doit_prologue() {
  assert(Thread::current()->is_Java_thread(), "just checking");

  // Load AbstractOwnableSynchronizer class
  if (_concurrent_locks && JDK_Version::is_gte_jdk16x_version()) {
    java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
  }

  return true;
}

void VM_FindDeadlocks::doit() {
  _deadlocks = ThreadService::find_deadlocks_at_safepoint(_concurrent_locks);
  if (_out != NULL) {
    int num_deadlocks = 0;
    for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) {
      num_deadlocks++;
      cycle->print_on(_out);
    }

    if (num_deadlocks == 1) {
      _out->print_cr("\nFound 1 deadlock.\n");
      _out->flush();
    } else if (num_deadlocks > 1) {
      _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks);
      _out->flush();
    }
  }
}

VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
                             int max_depth,
                             bool with_locked_monitors,
                             bool with_locked_synchronizers) {
  _result = result;
  _num_threads = 0; // 0 indicates all threads
  _threads = NULL;
  _result = result;
  _max_depth = max_depth;
  _with_locked_monitors = with_locked_monitors;
  _with_locked_synchronizers = with_locked_synchronizers;
}

VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
                             GrowableArray<instanceHandle>* threads,
                             int num_threads,
                             int max_depth,
                             bool with_locked_monitors,
                             bool with_locked_synchronizers) {
  _result = result;
  _num_threads = num_threads;
  _threads = threads;
  _result = result;
  _max_depth = max_depth;
  _with_locked_monitors = with_locked_monitors;
  _with_locked_synchronizers = with_locked_synchronizers;
}

bool VM_ThreadDump::doit_prologue() {
  assert(Thread::current()->is_Java_thread(), "just checking");

  // Load AbstractOwnableSynchronizer class before taking thread snapshots
  if (JDK_Version::is_gte_jdk16x_version()) {
    java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
  }

  if (_with_locked_synchronizers) {
    // Acquire Heap_lock to dump concurrent locks
    Heap_lock->lock();
  }

  return true;
}

void VM_ThreadDump::doit_epilogue() {
  if (_with_locked_synchronizers) {
    // Release Heap_lock
    Heap_lock->unlock();
  }
}

void VM_ThreadDump::doit() {
  ResourceMark rm;

  ConcurrentLocksDump concurrent_locks(true);
  if (_with_locked_synchronizers) {
    concurrent_locks.dump_at_safepoint();
  }

  if (_num_threads == 0) {
    // Snapshot all live threads
    for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
      if (jt->is_exiting() ||
          jt->is_hidden_from_external_view())  {
        // skip terminating threads and hidden threads
        continue;
      }
      ThreadConcurrentLocks* tcl = NULL;
      if (_with_locked_synchronizers) {
        tcl = concurrent_locks.thread_concurrent_locks(jt);
      }
      ThreadSnapshot* ts = snapshot_thread(jt, tcl);
      _result->add_thread_snapshot(ts);
    }
  } else {
    // Snapshot threads in the given _threads array
    // A dummy snapshot is created if a thread doesn't exist
    for (int i = 0; i < _num_threads; i++) {
      instanceHandle th = _threads->at(i);
      if (th() == NULL) {
        // skip if the thread doesn't exist
        // Add a dummy snapshot
        _result->add_thread_snapshot(new ThreadSnapshot());
        continue;
      }

      // Dump thread stack only if the thread is alive and not exiting
      // and not VM internal thread.
      JavaThread* jt = java_lang_Thread::thread(th());
      if (jt == NULL || /* thread not alive */
          jt->is_exiting() ||
          jt->is_hidden_from_external_view())  {
        // add a NULL snapshot if skipped
        _result->add_thread_snapshot(new ThreadSnapshot());
        continue;
      }
      ThreadConcurrentLocks* tcl = NULL;
      if (_with_locked_synchronizers) {
        tcl = concurrent_locks.thread_concurrent_locks(jt);
      }
      ThreadSnapshot* ts = snapshot_thread(jt, tcl);
      _result->add_thread_snapshot(ts);
    }
  }
}

ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) {
  ThreadSnapshot* snapshot = new ThreadSnapshot(java_thread);
  snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors);
  snapshot->set_concurrent_locks(tcl);
  return snapshot;
}

volatile bool VM_Exit::_vm_exited = false;
Thread * VM_Exit::_shutdown_thread = NULL;

int VM_Exit::set_vm_exited() {
  Thread * thr_cur = ThreadLocalStorage::get_thread_slow();

  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");

  int num_active = 0;

  _shutdown_thread = thr_cur;
  _vm_exited = true;                                // global flag
  for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next())
    if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
      ++num_active;
      thr->set_terminated(JavaThread::_vm_exited);  // per-thread flag
    }

  return num_active;
}

int VM_Exit::wait_for_threads_in_native_to_block() {
  // VM exits at safepoint. This function must be called at the final safepoint
  // to wait for threads in _thread_in_native state to be quiescent.
  assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");

  Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
  Monitor timer(Mutex::leaf, "VM_Exit timer", true);

  // Compiler threads need longer wait because they can access VM data directly
  // while in native. If they are active and some structures being used are
  // deleted by the shutdown sequence, they will crash. On the other hand, user
  // threads must go through native=>Java/VM transitions first to access VM
  // data, and they will be stopped during state transition. In theory, we
  // don't have to wait for user threads to be quiescent, but it's always
  // better to terminate VM when current thread is the only active thread, so
  // wait for user threads too. Numbers are in 10 milliseconds.
  int max_wait_user_thread = 30;                  // at least 300 milliseconds
  int max_wait_compiler_thread = 1000;            // at least 10 seconds

  int max_wait = max_wait_compiler_thread;

  int attempts = 0;
  while (true) {
    int num_active = 0;
    int num_active_compiler_thread = 0;

    for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) {
      if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
        num_active++;
        if (thr->is_Compiler_thread()) {
          num_active_compiler_thread++;
        }
      }
    }

    if (num_active == 0) {
       return 0;
    } else if (attempts > max_wait) {
       return num_active;
    } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
       return num_active;
    }

    attempts++;

    MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
    timer.wait(Mutex::_no_safepoint_check_flag, 10);
  }
}

void VM_Exit::doit() {
  CompileBroker::set_should_block();

  // Wait for a short period for threads in native to block. Any thread
  // still executing native code after the wait will be stopped at
  // native==>Java/VM barriers.
  // Among 16276 JCK tests, 94% of them come here without any threads still
  // running in native; the other 6% are quiescent within 250ms (Ultra 80).
  wait_for_threads_in_native_to_block();

  set_vm_exited();

  // cleanup globals resources before exiting. exit_globals() currently
  // cleans up outputStream resources and PerfMemory resources.
  exit_globals();

  // Check for exit hook
  exit_hook_t exit_hook = Arguments::exit_hook();
  if (exit_hook != NULL) {
    // exit hook should exit.
    exit_hook(_exit_code);
    // ... but if it didn't, we must do it here
    vm_direct_exit(_exit_code);
  } else {
    vm_direct_exit(_exit_code);
  }
}


void VM_Exit::wait_if_vm_exited() {
  if (_vm_exited &&
      ThreadLocalStorage::get_thread_slow() != _shutdown_thread) {
    // _vm_exited is set at safepoint, and the Threads_lock is never released
    // we will block here until the process dies
    Threads_lock->lock_without_safepoint_check();
    ShouldNotReachHere();
  }
}