aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #include "precompiled.hpp"
aoqi@0: #include "classfile/symbolTable.hpp"
aoqi@0: #include "classfile/vmSymbols.hpp"
aoqi@0: #include "compiler/compileBroker.hpp"
aoqi@0: #include "compiler/compilerOracle.hpp"
aoqi@0: #include "gc_implementation/shared/isGCActiveMark.hpp"
aoqi@0: #include "memory/resourceArea.hpp"
aoqi@0: #include "oops/symbol.hpp"
aoqi@0: #include "runtime/arguments.hpp"
aoqi@0: #include "runtime/deoptimization.hpp"
aoqi@0: #include "runtime/interfaceSupport.hpp"
aoqi@0: #include "runtime/sweeper.hpp"
aoqi@0: #include "runtime/thread.inline.hpp"
aoqi@0: #include "runtime/vm_operations.hpp"
aoqi@0: #include "services/threadService.hpp"
aoqi@0: #include "trace/tracing.hpp"
aoqi@0: 
aoqi@0: PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
aoqi@0: 
aoqi@0: #define VM_OP_NAME_INITIALIZE(name) #name,
aoqi@0: 
aoqi@0: const char* VM_Operation::_names[VM_Operation::VMOp_Terminating] = \
aoqi@0:   { VM_OPS_DO(VM_OP_NAME_INITIALIZE) };
aoqi@0: 
aoqi@0: void VM_Operation::set_calling_thread(Thread* thread, ThreadPriority priority) {
aoqi@0:   _calling_thread = thread;
aoqi@0:   assert(MinPriority <= priority && priority <= MaxPriority, "sanity check");
aoqi@0:   _priority = priority;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void VM_Operation::evaluate() {
aoqi@0:   ResourceMark rm;
aoqi@0:   if (TraceVMOperation) {
aoqi@0:     tty->print("[");
aoqi@0:     NOT_PRODUCT(print();)
aoqi@0:   }
aoqi@0:   doit();
aoqi@0:   if (TraceVMOperation) {
aoqi@0:     tty->print_cr("]");
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: const char* VM_Operation::mode_to_string(Mode mode) {
aoqi@0:   switch(mode) {
aoqi@0:     case _safepoint      : return "safepoint";
aoqi@0:     case _no_safepoint   : return "no safepoint";
aoqi@0:     case _concurrent     : return "concurrent";
aoqi@0:     case _async_safepoint: return "async safepoint";
aoqi@0:     default              : return "unknown";
aoqi@0:   }
aoqi@0: }
aoqi@0: // Called by fatal error handler.
aoqi@0: void VM_Operation::print_on_error(outputStream* st) const {
aoqi@0:   st->print("VM_Operation (" PTR_FORMAT "): ", this);
aoqi@0:   st->print("%s", name());
aoqi@0: 
aoqi@0:   const char* mode = mode_to_string(evaluation_mode());
aoqi@0:   st->print(", mode: %s", mode);
aoqi@0: 
aoqi@0:   if (calling_thread()) {
aoqi@0:     st->print(", requested by thread " PTR_FORMAT, calling_thread());
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_ThreadStop::doit() {
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "must be at a safepoint");
aoqi@0:   JavaThread* target = java_lang_Thread::thread(target_thread());
aoqi@0:   // Note that this now allows multiple ThreadDeath exceptions to be
aoqi@0:   // thrown at a thread.
aoqi@0:   if (target != NULL) {
aoqi@0:     // the thread has run and is not already in the process of exiting
aoqi@0:     target->send_thread_stop(throwable());
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_Deoptimize::doit() {
aoqi@0:   // We do not want any GCs to happen while we are in the middle of this VM operation
aoqi@0:   ResourceMark rm;
aoqi@0:   DeoptimizationMarker dm;
aoqi@0: 
aoqi@0:   // Deoptimize all activations depending on marked nmethods
aoqi@0:   Deoptimization::deoptimize_dependents();
aoqi@0: 
thartmann@8074:   // Make the dependent methods not entrant
thartmann@8074:   CodeCache::make_marked_nmethods_not_entrant();
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: VM_DeoptimizeFrame::VM_DeoptimizeFrame(JavaThread* thread, intptr_t* id) {
aoqi@0:   _thread = thread;
aoqi@0:   _id     = id;
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void VM_DeoptimizeFrame::doit() {
aoqi@0:   Deoptimization::deoptimize_frame_internal(_thread, _id);
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: #ifndef PRODUCT
aoqi@0: 
aoqi@0: void VM_DeoptimizeAll::doit() {
aoqi@0:   DeoptimizationMarker dm;
aoqi@0:   // deoptimize all java threads in the system
aoqi@0:   if (DeoptimizeALot) {
aoqi@0:     for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
aoqi@0:       if (thread->has_last_Java_frame()) {
aoqi@0:         thread->deoptimize();
aoqi@0:       }
aoqi@0:     }
aoqi@0:   } else if (DeoptimizeRandom) {
aoqi@0: 
aoqi@0:     // Deoptimize some selected threads and frames
aoqi@0:     int tnum = os::random() & 0x3;
aoqi@0:     int fnum =  os::random() & 0x3;
aoqi@0:     int tcount = 0;
aoqi@0:     for (JavaThread* thread = Threads::first(); thread != NULL; thread = thread->next()) {
aoqi@0:       if (thread->has_last_Java_frame()) {
aoqi@0:         if (tcount++ == tnum)  {
aoqi@0:         tcount = 0;
aoqi@0:           int fcount = 0;
aoqi@0:           // Deoptimize some selected frames.
aoqi@0:           // Biased llocking wants a updated register map
aoqi@0:           for(StackFrameStream fst(thread, UseBiasedLocking); !fst.is_done(); fst.next()) {
aoqi@0:             if (fst.current()->can_be_deoptimized()) {
aoqi@0:               if (fcount++ == fnum) {
aoqi@0:                 fcount = 0;
aoqi@0:                 Deoptimization::deoptimize(thread, *fst.current(), fst.register_map());
aoqi@0:               }
aoqi@0:             }
aoqi@0:           }
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void VM_ZombieAll::doit() {
aoqi@0:   JavaThread *thread = (JavaThread *)calling_thread();
aoqi@0:   assert(thread->is_Java_thread(), "must be a Java thread");
aoqi@0:   thread->make_zombies();
aoqi@0: }
aoqi@0: 
aoqi@0: #endif // !PRODUCT
aoqi@0: 
aoqi@0: void VM_UnlinkSymbols::doit() {
aoqi@0:   JavaThread *thread = (JavaThread *)calling_thread();
aoqi@0:   assert(thread->is_Java_thread(), "must be a Java thread");
aoqi@0:   SymbolTable::unlink();
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_Verify::doit() {
aoqi@0:   Universe::heap()->prepare_for_verify();
aoqi@0:   Universe::verify(_silent);
aoqi@0: }
aoqi@0: 
aoqi@0: bool VM_PrintThreads::doit_prologue() {
aoqi@0:   assert(Thread::current()->is_Java_thread(), "just checking");
aoqi@0: 
aoqi@0:   // Make sure AbstractOwnableSynchronizer is loaded
aoqi@0:   if (JDK_Version::is_gte_jdk16x_version()) {
aoqi@0:     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get Heap_lock if concurrent locks will be dumped
aoqi@0:   if (_print_concurrent_locks) {
aoqi@0:     Heap_lock->lock();
aoqi@0:   }
aoqi@0:   return true;
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_PrintThreads::doit() {
aoqi@0:   Threads::print_on(_out, true, false, _print_concurrent_locks);
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_PrintThreads::doit_epilogue() {
aoqi@0:   if (_print_concurrent_locks) {
aoqi@0:     // Release Heap_lock
aoqi@0:     Heap_lock->unlock();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_PrintJNI::doit() {
aoqi@0:   JNIHandles::print_on(_out);
aoqi@0: }
aoqi@0: 
aoqi@0: VM_FindDeadlocks::~VM_FindDeadlocks() {
aoqi@0:   if (_deadlocks != NULL) {
aoqi@0:     DeadlockCycle* cycle = _deadlocks;
aoqi@0:     while (cycle != NULL) {
aoqi@0:       DeadlockCycle* d = cycle;
aoqi@0:       cycle = cycle->next();
aoqi@0:       delete d;
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: bool VM_FindDeadlocks::doit_prologue() {
aoqi@0:   assert(Thread::current()->is_Java_thread(), "just checking");
aoqi@0: 
aoqi@0:   // Load AbstractOwnableSynchronizer class
aoqi@0:   if (_concurrent_locks && JDK_Version::is_gte_jdk16x_version()) {
aoqi@0:     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
aoqi@0:   }
aoqi@0: 
aoqi@0:   return true;
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_FindDeadlocks::doit() {
aoqi@0:   _deadlocks = ThreadService::find_deadlocks_at_safepoint(_concurrent_locks);
aoqi@0:   if (_out != NULL) {
aoqi@0:     int num_deadlocks = 0;
aoqi@0:     for (DeadlockCycle* cycle = _deadlocks; cycle != NULL; cycle = cycle->next()) {
aoqi@0:       num_deadlocks++;
aoqi@0:       cycle->print_on(_out);
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (num_deadlocks == 1) {
aoqi@0:       _out->print_cr("\nFound 1 deadlock.\n");
aoqi@0:       _out->flush();
aoqi@0:     } else if (num_deadlocks > 1) {
aoqi@0:       _out->print_cr("\nFound %d deadlocks.\n", num_deadlocks);
aoqi@0:       _out->flush();
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
aoqi@0:                              int max_depth,
aoqi@0:                              bool with_locked_monitors,
aoqi@0:                              bool with_locked_synchronizers) {
aoqi@0:   _result = result;
aoqi@0:   _num_threads = 0; // 0 indicates all threads
aoqi@0:   _threads = NULL;
aoqi@0:   _result = result;
aoqi@0:   _max_depth = max_depth;
aoqi@0:   _with_locked_monitors = with_locked_monitors;
aoqi@0:   _with_locked_synchronizers = with_locked_synchronizers;
aoqi@0: }
aoqi@0: 
aoqi@0: VM_ThreadDump::VM_ThreadDump(ThreadDumpResult* result,
aoqi@0:                              GrowableArray<instanceHandle>* threads,
aoqi@0:                              int num_threads,
aoqi@0:                              int max_depth,
aoqi@0:                              bool with_locked_monitors,
aoqi@0:                              bool with_locked_synchronizers) {
aoqi@0:   _result = result;
aoqi@0:   _num_threads = num_threads;
aoqi@0:   _threads = threads;
aoqi@0:   _result = result;
aoqi@0:   _max_depth = max_depth;
aoqi@0:   _with_locked_monitors = with_locked_monitors;
aoqi@0:   _with_locked_synchronizers = with_locked_synchronizers;
aoqi@0: }
aoqi@0: 
aoqi@0: bool VM_ThreadDump::doit_prologue() {
aoqi@0:   assert(Thread::current()->is_Java_thread(), "just checking");
aoqi@0: 
aoqi@0:   // Load AbstractOwnableSynchronizer class before taking thread snapshots
aoqi@0:   if (JDK_Version::is_gte_jdk16x_version()) {
aoqi@0:     java_util_concurrent_locks_AbstractOwnableSynchronizer::initialize(JavaThread::current());
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (_with_locked_synchronizers) {
aoqi@0:     // Acquire Heap_lock to dump concurrent locks
aoqi@0:     Heap_lock->lock();
aoqi@0:   }
aoqi@0: 
aoqi@0:   return true;
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_ThreadDump::doit_epilogue() {
aoqi@0:   if (_with_locked_synchronizers) {
aoqi@0:     // Release Heap_lock
aoqi@0:     Heap_lock->unlock();
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_ThreadDump::doit() {
aoqi@0:   ResourceMark rm;
aoqi@0: 
aoqi@0:   ConcurrentLocksDump concurrent_locks(true);
aoqi@0:   if (_with_locked_synchronizers) {
aoqi@0:     concurrent_locks.dump_at_safepoint();
aoqi@0:   }
aoqi@0: 
aoqi@0:   if (_num_threads == 0) {
aoqi@0:     // Snapshot all live threads
aoqi@0:     for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
aoqi@0:       if (jt->is_exiting() ||
aoqi@0:           jt->is_hidden_from_external_view())  {
aoqi@0:         // skip terminating threads and hidden threads
aoqi@0:         continue;
aoqi@0:       }
aoqi@0:       ThreadConcurrentLocks* tcl = NULL;
aoqi@0:       if (_with_locked_synchronizers) {
aoqi@0:         tcl = concurrent_locks.thread_concurrent_locks(jt);
aoqi@0:       }
aoqi@0:       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
aoqi@0:       _result->add_thread_snapshot(ts);
aoqi@0:     }
aoqi@0:   } else {
aoqi@0:     // Snapshot threads in the given _threads array
aoqi@0:     // A dummy snapshot is created if a thread doesn't exist
aoqi@0:     for (int i = 0; i < _num_threads; i++) {
aoqi@0:       instanceHandle th = _threads->at(i);
aoqi@0:       if (th() == NULL) {
aoqi@0:         // skip if the thread doesn't exist
aoqi@0:         // Add a dummy snapshot
aoqi@0:         _result->add_thread_snapshot(new ThreadSnapshot());
aoqi@0:         continue;
aoqi@0:       }
aoqi@0: 
aoqi@0:       // Dump thread stack only if the thread is alive and not exiting
aoqi@0:       // and not VM internal thread.
aoqi@0:       JavaThread* jt = java_lang_Thread::thread(th());
aoqi@0:       if (jt == NULL || /* thread not alive */
aoqi@0:           jt->is_exiting() ||
aoqi@0:           jt->is_hidden_from_external_view())  {
aoqi@0:         // add a NULL snapshot if skipped
aoqi@0:         _result->add_thread_snapshot(new ThreadSnapshot());
aoqi@0:         continue;
aoqi@0:       }
aoqi@0:       ThreadConcurrentLocks* tcl = NULL;
aoqi@0:       if (_with_locked_synchronizers) {
aoqi@0:         tcl = concurrent_locks.thread_concurrent_locks(jt);
aoqi@0:       }
aoqi@0:       ThreadSnapshot* ts = snapshot_thread(jt, tcl);
aoqi@0:       _result->add_thread_snapshot(ts);
aoqi@0:     }
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: ThreadSnapshot* VM_ThreadDump::snapshot_thread(JavaThread* java_thread, ThreadConcurrentLocks* tcl) {
aoqi@0:   ThreadSnapshot* snapshot = new ThreadSnapshot(java_thread);
aoqi@0:   snapshot->dump_stack_at_safepoint(_max_depth, _with_locked_monitors);
aoqi@0:   snapshot->set_concurrent_locks(tcl);
aoqi@0:   return snapshot;
aoqi@0: }
aoqi@0: 
aoqi@0: volatile bool VM_Exit::_vm_exited = false;
aoqi@0: Thread * VM_Exit::_shutdown_thread = NULL;
aoqi@0: 
aoqi@0: int VM_Exit::set_vm_exited() {
aoqi@0:   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
aoqi@0: 
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
aoqi@0: 
aoqi@0:   int num_active = 0;
aoqi@0: 
aoqi@0:   _shutdown_thread = thr_cur;
aoqi@0:   _vm_exited = true;                                // global flag
aoqi@0:   for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next())
aoqi@0:     if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
aoqi@0:       ++num_active;
aoqi@0:       thr->set_terminated(JavaThread::_vm_exited);  // per-thread flag
aoqi@0:     }
aoqi@0: 
aoqi@0:   return num_active;
aoqi@0: }
aoqi@0: 
aoqi@0: int VM_Exit::wait_for_threads_in_native_to_block() {
aoqi@0:   // VM exits at safepoint. This function must be called at the final safepoint
aoqi@0:   // to wait for threads in _thread_in_native state to be quiescent.
aoqi@0:   assert(SafepointSynchronize::is_at_safepoint(), "must be at safepoint already");
aoqi@0: 
aoqi@0:   Thread * thr_cur = ThreadLocalStorage::get_thread_slow();
aoqi@0:   Monitor timer(Mutex::leaf, "VM_Exit timer", true);
aoqi@0: 
aoqi@0:   // Compiler threads need longer wait because they can access VM data directly
aoqi@0:   // while in native. If they are active and some structures being used are
aoqi@0:   // deleted by the shutdown sequence, they will crash. On the other hand, user
aoqi@0:   // threads must go through native=>Java/VM transitions first to access VM
aoqi@0:   // data, and they will be stopped during state transition. In theory, we
aoqi@0:   // don't have to wait for user threads to be quiescent, but it's always
aoqi@0:   // better to terminate VM when current thread is the only active thread, so
aoqi@0:   // wait for user threads too. Numbers are in 10 milliseconds.
aoqi@0:   int max_wait_user_thread = 30;                  // at least 300 milliseconds
aoqi@0:   int max_wait_compiler_thread = 1000;            // at least 10 seconds
aoqi@0: 
aoqi@0:   int max_wait = max_wait_compiler_thread;
aoqi@0: 
aoqi@0:   int attempts = 0;
aoqi@0:   while (true) {
aoqi@0:     int num_active = 0;
aoqi@0:     int num_active_compiler_thread = 0;
aoqi@0: 
aoqi@0:     for(JavaThread *thr = Threads::first(); thr != NULL; thr = thr->next()) {
aoqi@0:       if (thr!=thr_cur && thr->thread_state() == _thread_in_native) {
aoqi@0:         num_active++;
aoqi@0:         if (thr->is_Compiler_thread()) {
aoqi@0:           num_active_compiler_thread++;
aoqi@0:         }
aoqi@0:       }
aoqi@0:     }
aoqi@0: 
aoqi@0:     if (num_active == 0) {
aoqi@0:        return 0;
aoqi@0:     } else if (attempts > max_wait) {
aoqi@0:        return num_active;
aoqi@0:     } else if (num_active_compiler_thread == 0 && attempts > max_wait_user_thread) {
aoqi@0:        return num_active;
aoqi@0:     }
aoqi@0: 
aoqi@0:     attempts++;
aoqi@0: 
aoqi@0:     MutexLockerEx ml(&timer, Mutex::_no_safepoint_check_flag);
aoqi@0:     timer.wait(Mutex::_no_safepoint_check_flag, 10);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: void VM_Exit::doit() {
aoqi@0:   CompileBroker::set_should_block();
aoqi@0: 
aoqi@0:   // Wait for a short period for threads in native to block. Any thread
aoqi@0:   // still executing native code after the wait will be stopped at
aoqi@0:   // native==>Java/VM barriers.
aoqi@0:   // Among 16276 JCK tests, 94% of them come here without any threads still
aoqi@0:   // running in native; the other 6% are quiescent within 250ms (Ultra 80).
aoqi@0:   wait_for_threads_in_native_to_block();
aoqi@0: 
aoqi@0:   set_vm_exited();
aoqi@0: 
aoqi@0:   // cleanup globals resources before exiting. exit_globals() currently
aoqi@0:   // cleans up outputStream resources and PerfMemory resources.
aoqi@0:   exit_globals();
aoqi@0: 
aoqi@0:   // Check for exit hook
aoqi@0:   exit_hook_t exit_hook = Arguments::exit_hook();
aoqi@0:   if (exit_hook != NULL) {
aoqi@0:     // exit hook should exit.
aoqi@0:     exit_hook(_exit_code);
aoqi@0:     // ... but if it didn't, we must do it here
aoqi@0:     vm_direct_exit(_exit_code);
aoqi@0:   } else {
aoqi@0:     vm_direct_exit(_exit_code);
aoqi@0:   }
aoqi@0: }
aoqi@0: 
aoqi@0: 
aoqi@0: void VM_Exit::wait_if_vm_exited() {
aoqi@0:   if (_vm_exited &&
aoqi@0:       ThreadLocalStorage::get_thread_slow() != _shutdown_thread) {
aoqi@0:     // _vm_exited is set at safepoint, and the Threads_lock is never released
aoqi@0:     // we will block here until the process dies
aoqi@0:     Threads_lock->lock_without_safepoint_check();
aoqi@0:     ShouldNotReachHere();
aoqi@0:   }
aoqi@0: }