rev 1083 : code cache unloading for webrev 091214
rev 1085 : checkpoint unloading changes on 100107

   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_HandleFullCodeCache::doit() {
 155   NMethodSweeper::speculative_disconnect_nmethods(_is_full);
 156 }
 157 
 158 void VM_Verify::doit() {
 159   Universe::verify();
 160 }
 161 
 162 bool VM_PrintThreads::doit_prologue() {
 163   assert(Thread::current()->is_Java_thread(), "just checking");
 164 
 165   // Make sure AbstractOwnableSynchronizer is loaded
 166   if (JDK_Version::is_gte_jdk16x_version()) {
 167     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
 168   }
 169 
 170   // Get Heap_lock if concurrent locks will be dumped
 171   if (_print_concurrent_locks) {
 172     Heap_lock->lock();
 173   }
 174   return true;
 175 }
 176 
 177 void VM_PrintThreads::doit() {
 178   Threads::print_on(_out, true, false, _print_concurrent_locks);
 179 }
 180 
 181 void VM_PrintThreads::doit_epilogue() {
 182   if (_print_concurrent_locks) {
 183     // Release Heap_lock
 184     Heap_lock->unlock();
 185   }
 186 }
 187 
 188 void VM_PrintJNI::doit() {
 189   JNIHandles::print_on(_out);
 190 }
 191 
 192 VM_FindDeadlocks::~VM_FindDeadlocks() {
 193   if (_deadlocks != NULL) {
 194     DeadlockCycle* cycle = _deadlocks;
 195     while (cycle != NULL) {
 196       DeadlockCycle* d = cycle;
 197       cycle = cycle->next();
 198       delete d;
 199     }
 200   }
 201 }
 202 
 203 bool VM_FindDeadlocks::doit_prologue() {
 204   assert(Thread::current()->is_Java_thread(), "just checking");
 205 
 206   // Load AbstractOwnableSynchronizer class
 207   if (_concurrent_locks && JDK_Version::is_gte_jdk16x_version()) {
 208     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
 209   }
 210 
 211   return true;
 212 }
 213 
 214 void VM_FindDeadlocks::doit() {
 215   _deadlocks = ThreadService::find_deadlocks_at_safepoint(_concurrent_locks);
 216   if (_out != NULL) {
 217     int num_deadlocks = 0;
 218     for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) {
 219       num_deadlocks++;
 220       cycle->print_on(_out);
 221     }
 222 
 223     if (num_deadlocks == 1) {
 224       _out->print_cr("\nFound 1 deadlock.\n");
 225       _out->flush();
 226     } else if (num_deadlocks > 1) {
 227       _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks);
 228       _out->flush();
 229     }
 230   }
 231 }
 232 
 233 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
 234                              int max_depth,
 235                              bool with_locked_monitors,
 236                              bool with_locked_synchronizers) {
 237   _result = result;
 238   _num_threads = 0; // 0 indicates all threads
 239   _threads = NULL;
 240   _result = result;
 241   _max_depth = max_depth;
 242   _with_locked_monitors = with_locked_monitors;
 243   _with_locked_synchronizers = with_locked_synchronizers;
 244 }
 245 
 246 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
 247                              GrowableArray<instanceHandle>* threads,
 248                              int num_threads,
 249                              int max_depth,
 250                              bool with_locked_monitors,
 251                              bool with_locked_synchronizers) {
 252   _result = result;
 253   _num_threads = num_threads;
 254   _threads = threads;
 255   _result = result;
 256   _max_depth = max_depth;
 257   _with_locked_monitors = with_locked_monitors;
 258   _with_locked_synchronizers = with_locked_synchronizers;
 259 }
 260 
 261 bool VM_ThreadDump::doit_prologue() {
 262   assert(Thread::current()->is_Java_thread(), "just checking");
 263 
 264   // Load AbstractOwnableSynchronizer class before taking thread snapshots
 265   if (JDK_Version::is_gte_jdk16x_version()) {
 266     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
 267   }
 268 
 269   if (_with_locked_synchronizers) {
 270     // Acquire Heap_lock to dump concurrent locks
 271     Heap_lock->lock();
 272   }
 273 
 274   return true;
 275 }
 276 
 277 void VM_ThreadDump::doit_epilogue() {
 278   if (_with_locked_synchronizers) {
 279     // Release Heap_lock
 280     Heap_lock->unlock();
 281   }
 282 }
 283 
 284 void VM_ThreadDump::doit() {
 285   ResourceMark rm;
 286 
 287   ConcurrentLocksDump concurrent_locks(true);
 288   if (_with_locked_synchronizers) {
 289     concurrent_locks.dump_at_safepoint();
 290   }
 291 
 292   if (_num_threads == 0) {
 293     // Snapshot all live threads
 294     for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
 295       if (jt->is_exiting() ||
 296           jt->is_hidden_from_external_view())  {
 297         // skip terminating threads and hidden threads
 298         continue;
 299       }
 300       ThreadConcurrentLocks* tcl = NULL;
 301       if (_with_locked_synchronizers) {
 302         tcl = concurrent_locks.thread_concurrent_locks(jt);
 303       }
 304       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
 305       _result->add_thread_snapshot(ts);
 306     }
 307   } else {
 308     // Snapshot threads in the given _threads array
 309     // A dummy snapshot is created if a thread doesn't exist
 310     for (int i = 0; i < _num_threads; i++) {
 311       instanceHandle th = _threads->at(i);
 312       if (th() == NULL) {
 313         // skip if the thread doesn't exist
 314         // Add a dummy snapshot
 315         _result->add_thread_snapshot(new ThreadSnapshot());
 316         continue;
 317       }
 318 
 319       // Dump thread stack only if the thread is alive and not exiting
 320       // and not VM internal thread.
 321       JavaThread* jt = java_lang_Thread::thread(th());
 322       if (jt == NULL || /* thread not alive */
 323           jt->is_exiting() ||
 324           jt->is_hidden_from_external_view())  {
 325         // add a NULL snapshot if skipped
 326         _result->add_thread_snapshot(new ThreadSnapshot());
 327         continue;
 328       }
 329       ThreadConcurrentLocks* tcl = NULL;
 330       if (_with_locked_synchronizers) {
 331         tcl = concurrent_locks.thread_concurrent_locks(jt);
 332       }
 333       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
 334       _result->add_thread_snapshot(ts);
 335     }
 336   }
 337 }
 338 
 339 ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) {
 340   ThreadSnapshot* snapshot = new ThreadSnapshot(java_thread);
 341   snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors);
 342   snapshot->set_concurrent_locks(tcl);
 343   return snapshot;
 344 }
 345 
 346 volatile bool VM_Exit::_vm_exited = false;
 347 Thread * VM_Exit::_shutdown_thread = NULL;
 348 
 349 int VM_Exit::set_vm_exited() {
 350   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
 351 
 352   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
 353 
 354   int num_active = 0;
 355 
 356   _shutdown_thread = thr_cur;
 357   _vm_exited = true;                                // global flag
 358   for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next())
 359     if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
 360       ++num_active;
 361       thr->set_terminated(JavaThread::_vm_exited);  // per-thread flag
 362     }
 363 
 364   return num_active;
 365 }
 366 
 367 int VM_Exit::wait_for_threads_in_native_to_block() {
 368   // VM exits at safepoint. This function must be called at the final safepoint
 369   // to wait for threads in _thread_in_native state to be quiescent.
 370   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
 371 
 372   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
 373   Monitor timer(Mutex::leaf, "VM_Exit timer", true);
 374 
 375   // Compiler threads need longer wait because they can access VM data directly
 376   // while in native. If they are active and some structures being used are
 377   // deleted by the shutdown sequence, they will crash. On the other hand, user
 378   // threads must go through native=>Java/VM transitions first to access VM
 379   // data, and they will be stopped during state transition. In theory, we
 380   // don't have to wait for user threads to be quiescent, but it's always
 381   // better to terminate VM when current thread is the only active thread, so
 382   // wait for user threads too. Numbers are in 10 milliseconds.
 383   int max_wait_user_thread = 30;                  // at least 300 milliseconds
 384   int max_wait_compiler_thread = 1000;            // at least 10 seconds
 385 
 386   int max_wait = max_wait_compiler_thread;
 387 
 388   int attempts = 0;
 389   while (true) {
 390     int num_active = 0;
 391     int num_active_compiler_thread = 0;
 392 
 393     for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) {
 394       if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
 395         num_active++;
 396         if (thr->is_Compiler_thread()) {
 397           num_active_compiler_thread++;
 398         }
 399       }
 400     }
 401 
 402     if (num_active == 0) {
 403        return 0;
 404     } else if (attempts > max_wait) {
 405        return num_active;
 406     } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
 407        return num_active;
 408     }
 409 
 410     attempts++;
 411 
 412     MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
 413     timer.wait(Mutex::_no_safepoint_check_flag, 10);
 414   }
 415 }
 416 
 417 void VM_Exit::doit() {
 418   CompileBroker::set_should_block();
 419 
 420   // Wait for a short period for threads in native to block. Any thread
 421   // still executing native code after the wait will be stopped at
 422   // native==>Java/VM barriers.
 423   // Among 16276 JCK tests, 94% of them come here without any threads still
 424   // running in native; the other 6% are quiescent within 250ms (Ultra 80).
 425   wait_for_threads_in_native_to_block();
 426 
 427   set_vm_exited();
 428 
 429   // cleanup globals resources before exiting. exit_globals() currently
 430   // cleans up outputStream resources and PerfMemory resources.
 431   exit_globals();
 432 
 433   // Check for exit hook
 434   exit_hook_t exit_hook = Arguments::exit_hook();
 435   if (exit_hook != NULL) {
 436     // exit hook should exit.
 437     exit_hook(_exit_code);
 438     // ... but if it didn't, we must do it here
 439     vm_direct_exit(_exit_code);
 440   } else {
 441     vm_direct_exit(_exit_code);
 442   }
 443 }
 444 
 445 
 446 void VM_Exit::wait_if_vm_exited() {
 447   if (_vm_exited &&
 448       ThreadLocalStorage::get_thread_slow() != _shutdown_thread) {
 449     // _vm_exited is set at safepoint, and the Threads_lock is never released
 450     // we will block here until the process dies
 451     Threads_lock->lock_without_safepoint_check();
 452     ShouldNotReachHere();
 453   }
 454 }
--- EOF ---