rev 6793 : 8054889: Compiler team's implementation task
Summary: Adding three new diagnostic commands for compiler
Reviewed-by:

   1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/symbolTable.hpp"
  27 #include "classfile/vmSymbols.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "compiler/compileBroker.hpp"
  30 #include "compiler/compilerOracle.hpp"
  31 #include "gc_implementation/shared/isGCActiveMark.hpp"
  32 #include "memory/resourceArea.hpp"
  33 #include "oops/symbol.hpp"
  34 #include "runtime/arguments.hpp"
  35 #include "runtime/deoptimization.hpp"
  36 #include "runtime/interfaceSupport.hpp"
  37 #include "runtime/sweeper.hpp"
  38 #include "runtime/thread.inline.hpp"
  39 #include "runtime/vm_operations.hpp"
  40 #include "services/threadService.hpp"
  41 #include "trace/tracing.hpp"
  42 
  43 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
  44 
  45 #define VM_OP_NAME_INITIALIZE(name) #name,
  46 
  47 const char* VM_Operation::_names[VM_Operation::VMOp_Terminating] = \
  48   { VM_OPS_DO(VM_OP_NAME_INITIALIZE) };
  49 
  50 void VM_Operation::set_calling_thread(Thread* thread, ThreadPriority priority) {
  51   _calling_thread = thread;
  52   assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
  53   _priority = priority;
  54 }
  55 
  56 
  57 void VM_Operation::evaluate() {
  58   ResourceMark rm;
  59   if (TraceVMOperation) {
  60     tty->print("[");
  61     NOT_PRODUCT(print();)
  62   }
  63   doit();
  64   if (TraceVMOperation) {
  65     tty->print_cr("]");
  66   }
  67 }
  68 
  69 const char* VM_Operation::mode_to_string(Mode mode) {
  70   switch(mode) {
  71     case _safepoint      : return "safepoint";
  72     case _no_safepoint   : return "no safepoint";
  73     case _concurrent     : return "concurrent";
  74     case _async_safepoint: return "async safepoint";
  75     default              : return "unknown";
  76   }
  77 }
  78 // Called by fatal error handler.
  79 void VM_Operation::print_on_error(outputStream* st) const {
  80   st->print("VM_Operation (" PTR_FORMAT "): ", this);
  81   st->print("%s", name());
  82 
  83   const char* mode = mode_to_string(evaluation_mode());
  84   st->print(", mode: %s", mode);
  85 
  86   if (calling_thread()) {
  87     st->print(", requested by thread " PTR_FORMAT, calling_thread());
  88   }
  89 }
  90 
  91 void VM_ThreadStop::doit() {
  92   assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
  93   JavaThread* target = java_lang_Thread::thread(target_thread());
  94   // Note that this now allows multiple ThreadDeath exceptions to be
  95   // thrown at a thread.
  96   if (target != NULL) {
  97     // the thread has run and is not already in the process of exiting
  98     target->send_thread_stop(throwable());
  99   }
 100 }
 101 
 102 void VM_Deoptimize::doit() {
 103   // We do not want any GCs to happen while we are in the middle of this VM operation
 104   ResourceMark rm;
 105   DeoptimizationMarker dm;
 106 
 107   // Deoptimize all activations depending on marked nmethods
 108   Deoptimization::deoptimize_dependents();
 109 
 110   // Make the dependent methods zombies
 111   CodeCache::make_marked_nmethods_zombies();
 112 }
 113 
 114 
 115 VM_DeoptimizeFrame::VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id) {
 116   _thread = thread;
 117   _id     = id;
 118 }
 119 
 120 
 121 void VM_DeoptimizeFrame::doit() {
 122   Deoptimization::deoptimize_frame_internal(_thread, _id);
 123 }
 124 
 125 
 126 #ifndef PRODUCT
 127 
 128 void VM_DeoptimizeAll::doit() {
 129   DeoptimizationMarker dm;
 130   // deoptimize all java threads in the system
 131   if (DeoptimizeALot) {
 132     for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
 133       if (thread->has_last_Java_frame()) {
 134         thread->deoptimize();
 135       }
 136     }
 137   } else if (DeoptimizeRandom) {
 138 
 139     // Deoptimize some selected threads and frames
 140     int tnum = os::random() & 0x3;
 141     int fnum =  os::random() & 0x3;
 142     int tcount = 0;
 143     for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
 144       if (thread->has_last_Java_frame()) {
 145         if (tcount++ == tnum)  {
 146         tcount = 0;
 147           int fcount = 0;
 148           // Deoptimize some selected frames.
 149           // Biased llocking wants a updated register map
 150           for(StackFrameStream fst(thread, UseBiasedLocking); !fst.is_done(); fst.next()) {
 151             if (fst.current()->can_be_deoptimized()) {
 152               if (fcount++ == fnum) {
 153                 fcount = 0;
 154                 Deoptimization::deoptimize(thread, *fst.current(), fst.register_map());
 155               }
 156             }
 157           }
 158         }
 159       }
 160     }
 161   }
 162 }
 163 
 164 
 165 void VM_ZombieAll::doit() {
 166   JavaThread *thread = (JavaThread *)calling_thread();
 167   assert(thread->is_Java_thread(), "must be a Java thread");
 168   thread->make_zombies();
 169 }
 170 
 171 #endif // !PRODUCT
 172 
 173 void VM_UnlinkSymbols::doit() {
 174   JavaThread *thread = (JavaThread *)calling_thread();
 175   assert(thread->is_Java_thread(), "must be a Java thread");
 176   SymbolTable::unlink();
 177 }
 178 
 179 void VM_Verify::doit() {
 180   Universe::heap()->prepare_for_verify();
 181   Universe::verify(_silent);
 182 }
 183 
 184 bool VM_PrintThreads::doit_prologue() {
 185   assert(Thread::current()->is_Java_thread(), "just checking");
 186 
 187   // Make sure AbstractOwnableSynchronizer is loaded
 188   java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
 189 
 190   // Get Heap_lock if concurrent locks will be dumped
 191   if (_print_concurrent_locks) {
 192     Heap_lock->lock();
 193   }
 194   return true;
 195 }
 196 
 197 void VM_PrintThreads::doit() {
 198   Threads::print_on(_out, true, false, _print_concurrent_locks);
 199 }
 200 
 201 void VM_PrintThreads::doit_epilogue() {
 202   if (_print_concurrent_locks) {
 203     // Release Heap_lock
 204     Heap_lock->unlock();
 205   }
 206 }
 207 
 208 void VM_PrintJNI::doit() {
 209   JNIHandles::print_on(_out);
 210 }
 211 
 212 VM_FindDeadlocks::~VM_FindDeadlocks() {
 213   if (_deadlocks != NULL) {
 214     DeadlockCycle* cycle = _deadlocks;
 215     while (cycle != NULL) {
 216       DeadlockCycle* d = cycle;
 217       cycle = cycle->next();
 218       delete d;
 219     }
 220   }
 221 }
 222 
 223 bool VM_FindDeadlocks::doit_prologue() {
 224   assert(Thread::current()->is_Java_thread(), "just checking");
 225 
 226   // Load AbstractOwnableSynchronizer class
 227   if (_concurrent_locks) {
 228     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
 229   }
 230 
 231   return true;
 232 }
 233 
 234 void VM_FindDeadlocks::doit() {
 235   _deadlocks = ThreadService::find_deadlocks_at_safepoint(_concurrent_locks);
 236   if (_out != NULL) {
 237     int num_deadlocks = 0;
 238     for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) {
 239       num_deadlocks++;
 240       cycle->print_on(_out);
 241     }
 242 
 243     if (num_deadlocks == 1) {
 244       _out->print_cr("\nFound 1 deadlock.\n");
 245       _out->flush();
 246     } else if (num_deadlocks > 1) {
 247       _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks);
 248       _out->flush();
 249     }
 250   }
 251 }
 252 
 253 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
 254                              int max_depth,
 255                              bool with_locked_monitors,
 256                              bool with_locked_synchronizers) {
 257   _result = result;
 258   _num_threads = 0; // 0 indicates all threads
 259   _threads = NULL;
 260   _result = result;
 261   _max_depth = max_depth;
 262   _with_locked_monitors = with_locked_monitors;
 263   _with_locked_synchronizers = with_locked_synchronizers;
 264 }
 265 
 266 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
 267                              GrowableArray<instanceHandle>* threads,
 268                              int num_threads,
 269                              int max_depth,
 270                              bool with_locked_monitors,
 271                              bool with_locked_synchronizers) {
 272   _result = result;
 273   _num_threads = num_threads;
 274   _threads = threads;
 275   _result = result;
 276   _max_depth = max_depth;
 277   _with_locked_monitors = with_locked_monitors;
 278   _with_locked_synchronizers = with_locked_synchronizers;
 279 }
 280 
 281 bool VM_ThreadDump::doit_prologue() {
 282   assert(Thread::current()->is_Java_thread(), "just checking");
 283 
 284   // Load AbstractOwnableSynchronizer class before taking thread snapshots
 285   java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
 286 
 287   if (_with_locked_synchronizers) {
 288     // Acquire Heap_lock to dump concurrent locks
 289     Heap_lock->lock();
 290   }
 291 
 292   return true;
 293 }
 294 
 295 void VM_ThreadDump::doit_epilogue() {
 296   if (_with_locked_synchronizers) {
 297     // Release Heap_lock
 298     Heap_lock->unlock();
 299   }
 300 }
 301 
 302 void VM_ThreadDump::doit() {
 303   ResourceMark rm;
 304 
 305   ConcurrentLocksDump concurrent_locks(true);
 306   if (_with_locked_synchronizers) {
 307     concurrent_locks.dump_at_safepoint();
 308   }
 309 
 310   if (_num_threads == 0) {
 311     // Snapshot all live threads
 312     for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
 313       if (jt->is_exiting() ||
 314           jt->is_hidden_from_external_view())  {
 315         // skip terminating threads and hidden threads
 316         continue;
 317       }
 318       ThreadConcurrentLocks* tcl = NULL;
 319       if (_with_locked_synchronizers) {
 320         tcl = concurrent_locks.thread_concurrent_locks(jt);
 321       }
 322       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
 323       _result->add_thread_snapshot(ts);
 324     }
 325   } else {
 326     // Snapshot threads in the given _threads array
 327     // A dummy snapshot is created if a thread doesn't exist
 328     for (int i = 0; i < _num_threads; i++) {
 329       instanceHandle th = _threads->at(i);
 330       if (th() == NULL) {
 331         // skip if the thread doesn't exist
 332         // Add a dummy snapshot
 333         _result->add_thread_snapshot(new ThreadSnapshot());
 334         continue;
 335       }
 336 
 337       // Dump thread stack only if the thread is alive and not exiting
 338       // and not VM internal thread.
 339       JavaThread* jt = java_lang_Thread::thread(th());
 340       if (jt == NULL || /* thread not alive */
 341           jt->is_exiting() ||
 342           jt->is_hidden_from_external_view())  {
 343         // add a NULL snapshot if skipped
 344         _result->add_thread_snapshot(new ThreadSnapshot());
 345         continue;
 346       }
 347       ThreadConcurrentLocks* tcl = NULL;
 348       if (_with_locked_synchronizers) {
 349         tcl = concurrent_locks.thread_concurrent_locks(jt);
 350       }
 351       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
 352       _result->add_thread_snapshot(ts);
 353     }
 354   }
 355 }
 356 
 357 ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) {
 358   ThreadSnapshot* snapshot = new ThreadSnapshot(java_thread);
 359   snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors);
 360   snapshot->set_concurrent_locks(tcl);
 361   return snapshot;
 362 }
 363 
 364 volatile bool VM_Exit::_vm_exited = false;
 365 Thread * VM_Exit::_shutdown_thread = NULL;
 366 
 367 int VM_Exit::set_vm_exited() {
 368   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
 369 
 370   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
 371 
 372   int num_active = 0;
 373 
 374   _shutdown_thread = thr_cur;
 375   _vm_exited = true;                                // global flag
 376   for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next())
 377     if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
 378       ++num_active;
 379       thr->set_terminated(JavaThread::_vm_exited);  // per-thread flag
 380     }
 381 
 382   return num_active;
 383 }
 384 
 385 int VM_Exit::wait_for_threads_in_native_to_block() {
 386   // VM exits at safepoint. This function must be called at the final safepoint
 387   // to wait for threads in _thread_in_native state to be quiescent.
 388   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
 389 
 390   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
 391   Monitor timer(Mutex::leaf, "VM_Exit timer", true);
 392 
 393   // Compiler threads need longer wait because they can access VM data directly
 394   // while in native. If they are active and some structures being used are
 395   // deleted by the shutdown sequence, they will crash. On the other hand, user
 396   // threads must go through native=>Java/VM transitions first to access VM
 397   // data, and they will be stopped during state transition. In theory, we
 398   // don't have to wait for user threads to be quiescent, but it's always
 399   // better to terminate VM when current thread is the only active thread, so
 400   // wait for user threads too. Numbers are in 10 milliseconds.
 401   int max_wait_user_thread = 30;                  // at least 300 milliseconds
 402   int max_wait_compiler_thread = 1000;            // at least 10 seconds
 403 
 404   int max_wait = max_wait_compiler_thread;
 405 
 406   int attempts = 0;
 407   while (true) {
 408     int num_active = 0;
 409     int num_active_compiler_thread = 0;
 410 
 411     for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) {
 412       if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
 413         num_active++;
 414         if (thr->is_Compiler_thread()) {
 415           num_active_compiler_thread++;
 416         }
 417       }
 418     }
 419 
 420     if (num_active == 0) {
 421        return 0;
 422     } else if (attempts > max_wait) {
 423        return num_active;
 424     } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
 425        return num_active;
 426     }
 427 
 428     attempts++;
 429 
 430     MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
 431     timer.wait(Mutex::_no_safepoint_check_flag, 10);
 432   }
 433 }
 434 
 435 void VM_Exit::doit() {
 436   CompileBroker::set_should_block();
 437 
 438   // Wait for a short period for threads in native to block. Any thread
 439   // still executing native code after the wait will be stopped at
 440   // native==>Java/VM barriers.
 441   // Among 16276 JCK tests, 94% of them come here without any threads still
 442   // running in native; the other 6% are quiescent within 250ms (Ultra 80).
 443   wait_for_threads_in_native_to_block();
 444 
 445   set_vm_exited();
 446 
 447   // cleanup globals resources before exiting. exit_globals() currently
 448   // cleans up outputStream resources and PerfMemory resources.
 449   exit_globals();
 450 
 451   // Check for exit hook
 452   exit_hook_t exit_hook = Arguments::exit_hook();
 453   if (exit_hook != NULL) {
 454     // exit hook should exit.
 455     exit_hook(_exit_code);
 456     // ... but if it didn't, we must do it here
 457     vm_direct_exit(_exit_code);
 458   } else {
 459     vm_direct_exit(_exit_code);
 460   }
 461 }
 462 
 463 
 464 void VM_Exit::wait_if_vm_exited() {
 465   if (_vm_exited &&
 466       ThreadLocalStorage::get_thread_slow() != _shutdown_thread) {
 467     // _vm_exited is set at safepoint, and the Threads_lock is never released
 468     // we will block here until the process dies
 469     Threads_lock->lock_without_safepoint_check();
 470     ShouldNotReachHere();
 471   }
 472 }
 473 
 474 void VM_PrintCompileQueue::doit() {
 475   CompileBroker::print_compile_queues(_out);
 476 }
 477 
 478 void VM_PrintCodeList::doit() {
 479   CodeCache::print_codelist(_out);
 480 }
 481 
 482 void VM_PrintCodeCache::doit() {
 483   CodeCache::print_layout(_out);
 484 }
--- EOF ---