src/share/vm/runtime/vm_operations.cpp

Thu, 27 Jan 2011 16:11:27 -0800

author
coleenp
date
Thu, 27 Jan 2011 16:11:27 -0800
changeset 2497
3582bf76420e
parent 2314
f95d63e2154a
child 2708
1d1603768966
permissions
-rw-r--r--

6990754: Use native memory and reference counting to implement SymbolTable
Summary: move symbols from permgen into C heap and reference count them
Reviewed-by: never, acorn, jmasa, stefank

     1 /*
     2  * Copyright (c) 1997, 2010, 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  */
    25 #include "precompiled.hpp"
    26 #include "classfile/symbolTable.hpp"
    27 #include "classfile/vmSymbols.hpp"
    28 #include "compiler/compileBroker.hpp"
    29 #include "compiler/compilerOracle.hpp"
    30 #include "gc_implementation/shared/isGCActiveMark.hpp"
    31 #include "memory/resourceArea.hpp"
    32 #include "oops/symbol.hpp"
    33 #include "runtime/arguments.hpp"
    34 #include "runtime/deoptimization.hpp"
    35 #include "runtime/interfaceSupport.hpp"
    36 #include "runtime/sweeper.hpp"
    37 #include "runtime/vm_operations.hpp"
    38 #include "services/threadService.hpp"
    39 #ifdef TARGET_OS_FAMILY_linux
    40 # include "thread_linux.inline.hpp"
    41 #endif
    42 #ifdef TARGET_OS_FAMILY_solaris
    43 # include "thread_solaris.inline.hpp"
    44 #endif
    45 #ifdef TARGET_OS_FAMILY_windows
    46 # include "thread_windows.inline.hpp"
    47 #endif
    49 #define VM_OP_NAME_INITIALIZE(name) #name,
    51 const char* VM_Operation::_names[VM_Operation::VMOp_Terminating] = \
    52   { VM_OPS_DO(VM_OP_NAME_INITIALIZE) };
    54 void VM_Operation::set_calling_thread(Thread* thread, ThreadPriority priority) {
    55   _calling_thread = thread;
    56   assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
    57   _priority = priority;
    58 }
    61 void VM_Operation::evaluate() {
    62   ResourceMark rm;
    63   if (TraceVMOperation) {
    64     tty->print("[");
    65     NOT_PRODUCT(print();)
    66   }
    67   doit();
    68   if (TraceVMOperation) {
    69     tty->print_cr("]");
    70   }
    71 }
    73 // Called by fatal error handler.
    74 void VM_Operation::print_on_error(outputStream* st) const {
    75   st->print("VM_Operation (" PTR_FORMAT "): ", this);
    76   st->print("%s", name());
    78   const char* mode;
    79   switch(evaluation_mode()) {
    80     case _safepoint      : mode = "safepoint";       break;
    81     case _no_safepoint   : mode = "no safepoint";    break;
    82     case _concurrent     : mode = "concurrent";      break;
    83     case _async_safepoint: mode = "async safepoint"; break;
    84     default              : mode = "unknown";         break;
    85   }
    86   st->print(", mode: %s", mode);
    88   if (calling_thread()) {
    89     st->print(", requested by thread " PTR_FORMAT, calling_thread());
    90   }
    91 }
    93 void VM_ThreadStop::doit() {
    94   assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
    95   JavaThread* target = java_lang_Thread::thread(target_thread());
    96   // Note that this now allows multiple ThreadDeath exceptions to be
    97   // thrown at a thread.
    98   if (target != NULL) {
    99     // the thread has run and is not already in the process of exiting
   100     target->send_thread_stop(throwable());
   101   }
   102 }
   104 void VM_Deoptimize::doit() {
   105   // We do not want any GCs to happen while we are in the middle of this VM operation
   106   ResourceMark rm;
   107   DeoptimizationMarker dm;
   109   // Deoptimize all activations depending on marked nmethods
   110   Deoptimization::deoptimize_dependents();
   112   // Make the dependent methods zombies
   113   CodeCache::make_marked_nmethods_zombies();
   114 }
   117 VM_DeoptimizeFrame::VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id) {
   118   _thread = thread;
   119   _id     = id;
   120 }
   123 void VM_DeoptimizeFrame::doit() {
   124   Deoptimization::deoptimize_frame_internal(_thread, _id);
   125 }
   128 #ifndef PRODUCT
   130 void VM_DeoptimizeAll::doit() {
   131   DeoptimizationMarker dm;
   132   // deoptimize all java threads in the system
   133   if (DeoptimizeALot) {
   134     for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
   135       if (thread->has_last_Java_frame()) {
   136         thread->deoptimize();
   137       }
   138     }
   139   } else if (DeoptimizeRandom) {
   141     // Deoptimize some selected threads and frames
   142     int tnum = os::random() & 0x3;
   143     int fnum =  os::random() & 0x3;
   144     int tcount = 0;
   145     for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
   146       if (thread->has_last_Java_frame()) {
   147         if (tcount++ == tnum)  {
   148         tcount = 0;
   149           int fcount = 0;
   150           // Deoptimize some selected frames.
   151           // Biased llocking wants a updated register map
   152           for(StackFrameStream fst(thread, UseBiasedLocking); !fst.is_done(); fst.next()) {
   153             if (fst.current()->can_be_deoptimized()) {
   154               if (fcount++ == fnum) {
   155                 fcount = 0;
   156                 Deoptimization::deoptimize(thread, *fst.current(), fst.register_map());
   157               }
   158             }
   159           }
   160         }
   161       }
   162     }
   163   }
   164 }
   167 void VM_ZombieAll::doit() {
   168   JavaThread *thread = (JavaThread *)calling_thread();
   169   assert(thread->is_Java_thread(), "must be a Java thread");
   170   thread->make_zombies();
   171 }
   173 #endif // !PRODUCT
   175 void VM_UnlinkSymbols::doit() {
   176   JavaThread *thread = (JavaThread *)calling_thread();
   177   assert(thread->is_Java_thread(), "must be a Java thread");
   178   SymbolTable::unlink();
   179 }
   181 void VM_HandleFullCodeCache::doit() {
   182   NMethodSweeper::speculative_disconnect_nmethods(_is_full);
   183 }
   185 void VM_Verify::doit() {
   186   Universe::verify();
   187 }
   189 bool VM_PrintThreads::doit_prologue() {
   190   assert(Thread::current()->is_Java_thread(), "just checking");
   192   // Make sure AbstractOwnableSynchronizer is loaded
   193   if (JDK_Version::is_gte_jdk16x_version()) {
   194     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
   195   }
   197   // Get Heap_lock if concurrent locks will be dumped
   198   if (_print_concurrent_locks) {
   199     Heap_lock->lock();
   200   }
   201   return true;
   202 }
   204 void VM_PrintThreads::doit() {
   205   Threads::print_on(_out, true, false, _print_concurrent_locks);
   206 }
   208 void VM_PrintThreads::doit_epilogue() {
   209   if (_print_concurrent_locks) {
   210     // Release Heap_lock
   211     Heap_lock->unlock();
   212   }
   213 }
   215 void VM_PrintJNI::doit() {
   216   JNIHandles::print_on(_out);
   217 }
   219 VM_FindDeadlocks::~VM_FindDeadlocks() {
   220   if (_deadlocks != NULL) {
   221     DeadlockCycle* cycle = _deadlocks;
   222     while (cycle != NULL) {
   223       DeadlockCycle* d = cycle;
   224       cycle = cycle->next();
   225       delete d;
   226     }
   227   }
   228 }
   230 bool VM_FindDeadlocks::doit_prologue() {
   231   assert(Thread::current()->is_Java_thread(), "just checking");
   233   // Load AbstractOwnableSynchronizer class
   234   if (_concurrent_locks && JDK_Version::is_gte_jdk16x_version()) {
   235     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
   236   }
   238   return true;
   239 }
   241 void VM_FindDeadlocks::doit() {
   242   _deadlocks = ThreadService::find_deadlocks_at_safepoint(_concurrent_locks);
   243   if (_out != NULL) {
   244     int num_deadlocks = 0;
   245     for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) {
   246       num_deadlocks++;
   247       cycle->print_on(_out);
   248     }
   250     if (num_deadlocks == 1) {
   251       _out->print_cr("\nFound 1 deadlock.\n");
   252       _out->flush();
   253     } else if (num_deadlocks > 1) {
   254       _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks);
   255       _out->flush();
   256     }
   257   }
   258 }
   260 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
   261                              int max_depth,
   262                              bool with_locked_monitors,
   263                              bool with_locked_synchronizers) {
   264   _result = result;
   265   _num_threads = 0; // 0 indicates all threads
   266   _threads = NULL;
   267   _result = result;
   268   _max_depth = max_depth;
   269   _with_locked_monitors = with_locked_monitors;
   270   _with_locked_synchronizers = with_locked_synchronizers;
   271 }
   273 VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
   274                              GrowableArray<instanceHandle>* threads,
   275                              int num_threads,
   276                              int max_depth,
   277                              bool with_locked_monitors,
   278                              bool with_locked_synchronizers) {
   279   _result = result;
   280   _num_threads = num_threads;
   281   _threads = threads;
   282   _result = result;
   283   _max_depth = max_depth;
   284   _with_locked_monitors = with_locked_monitors;
   285   _with_locked_synchronizers = with_locked_synchronizers;
   286 }
   288 bool VM_ThreadDump::doit_prologue() {
   289   assert(Thread::current()->is_Java_thread(), "just checking");
   291   // Load AbstractOwnableSynchronizer class before taking thread snapshots
   292   if (JDK_Version::is_gte_jdk16x_version()) {
   293     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
   294   }
   296   if (_with_locked_synchronizers) {
   297     // Acquire Heap_lock to dump concurrent locks
   298     Heap_lock->lock();
   299   }
   301   return true;
   302 }
   304 void VM_ThreadDump::doit_epilogue() {
   305   if (_with_locked_synchronizers) {
   306     // Release Heap_lock
   307     Heap_lock->unlock();
   308   }
   309 }
   311 void VM_ThreadDump::doit() {
   312   ResourceMark rm;
   314   ConcurrentLocksDump concurrent_locks(true);
   315   if (_with_locked_synchronizers) {
   316     concurrent_locks.dump_at_safepoint();
   317   }
   319   if (_num_threads == 0) {
   320     // Snapshot all live threads
   321     for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
   322       if (jt->is_exiting() ||
   323           jt->is_hidden_from_external_view())  {
   324         // skip terminating threads and hidden threads
   325         continue;
   326       }
   327       ThreadConcurrentLocks* tcl = NULL;
   328       if (_with_locked_synchronizers) {
   329         tcl = concurrent_locks.thread_concurrent_locks(jt);
   330       }
   331       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
   332       _result->add_thread_snapshot(ts);
   333     }
   334   } else {
   335     // Snapshot threads in the given _threads array
   336     // A dummy snapshot is created if a thread doesn't exist
   337     for (int i = 0; i < _num_threads; i++) {
   338       instanceHandle th = _threads->at(i);
   339       if (th() == NULL) {
   340         // skip if the thread doesn't exist
   341         // Add a dummy snapshot
   342         _result->add_thread_snapshot(new ThreadSnapshot());
   343         continue;
   344       }
   346       // Dump thread stack only if the thread is alive and not exiting
   347       // and not VM internal thread.
   348       JavaThread* jt = java_lang_Thread::thread(th());
   349       if (jt == NULL || /* thread not alive */
   350           jt->is_exiting() ||
   351           jt->is_hidden_from_external_view())  {
   352         // add a NULL snapshot if skipped
   353         _result->add_thread_snapshot(new ThreadSnapshot());
   354         continue;
   355       }
   356       ThreadConcurrentLocks* tcl = NULL;
   357       if (_with_locked_synchronizers) {
   358         tcl = concurrent_locks.thread_concurrent_locks(jt);
   359       }
   360       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
   361       _result->add_thread_snapshot(ts);
   362     }
   363   }
   364 }
   366 ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) {
   367   ThreadSnapshot* snapshot = new ThreadSnapshot(java_thread);
   368   snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors);
   369   snapshot->set_concurrent_locks(tcl);
   370   return snapshot;
   371 }
   373 volatile bool VM_Exit::_vm_exited = false;
   374 Thread * VM_Exit::_shutdown_thread = NULL;
   376 int VM_Exit::set_vm_exited() {
   377   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
   379   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
   381   int num_active = 0;
   383   _shutdown_thread = thr_cur;
   384   _vm_exited = true;                                // global flag
   385   for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next())
   386     if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
   387       ++num_active;
   388       thr->set_terminated(JavaThread::_vm_exited);  // per-thread flag
   389     }
   391   return num_active;
   392 }
   394 int VM_Exit::wait_for_threads_in_native_to_block() {
   395   // VM exits at safepoint. This function must be called at the final safepoint
   396   // to wait for threads in _thread_in_native state to be quiescent.
   397   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
   399   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
   400   Monitor timer(Mutex::leaf, "VM_Exit timer", true);
   402   // Compiler threads need longer wait because they can access VM data directly
   403   // while in native. If they are active and some structures being used are
   404   // deleted by the shutdown sequence, they will crash. On the other hand, user
   405   // threads must go through native=>Java/VM transitions first to access VM
   406   // data, and they will be stopped during state transition. In theory, we
   407   // don't have to wait for user threads to be quiescent, but it's always
   408   // better to terminate VM when current thread is the only active thread, so
   409   // wait for user threads too. Numbers are in 10 milliseconds.
   410   int max_wait_user_thread = 30;                  // at least 300 milliseconds
   411   int max_wait_compiler_thread = 1000;            // at least 10 seconds
   413   int max_wait = max_wait_compiler_thread;
   415   int attempts = 0;
   416   while (true) {
   417     int num_active = 0;
   418     int num_active_compiler_thread = 0;
   420     for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) {
   421       if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
   422         num_active++;
   423         if (thr->is_Compiler_thread()) {
   424           num_active_compiler_thread++;
   425         }
   426       }
   427     }
   429     if (num_active == 0) {
   430        return 0;
   431     } else if (attempts > max_wait) {
   432        return num_active;
   433     } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
   434        return num_active;
   435     }
   437     attempts++;
   439     MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
   440     timer.wait(Mutex::_no_safepoint_check_flag, 10);
   441   }
   442 }
   444 void VM_Exit::doit() {
   445   CompileBroker::set_should_block();
   447   // Wait for a short period for threads in native to block. Any thread
   448   // still executing native code after the wait will be stopped at
   449   // native==>Java/VM barriers.
   450   // Among 16276 JCK tests, 94% of them come here without any threads still
   451   // running in native; the other 6% are quiescent within 250ms (Ultra 80).
   452   wait_for_threads_in_native_to_block();
   454   set_vm_exited();
   456   // cleanup globals resources before exiting. exit_globals() currently
   457   // cleans up outputStream resources and PerfMemory resources.
   458   exit_globals();
   460   // Check for exit hook
   461   exit_hook_t exit_hook = Arguments::exit_hook();
   462   if (exit_hook != NULL) {
   463     // exit hook should exit.
   464     exit_hook(_exit_code);
   465     // ... but if it didn't, we must do it here
   466     vm_direct_exit(_exit_code);
   467   } else {
   468     vm_direct_exit(_exit_code);
   469   }
   470 }
   473 void VM_Exit::wait_if_vm_exited() {
   474   if (_vm_exited &&
   475       ThreadLocalStorage::get_thread_slow() != _shutdown_thread) {
   476     // _vm_exited is set at safepoint, and the Threads_lock is never released
   477     // we will block here until the process dies
   478     Threads_lock->lock_without_safepoint_check();
   479     ShouldNotReachHere();
   480   }
   481 }

mercurial