jdk8-mips64-public/hotspot: src/share/vm/services/threadService.cpp@35f8765422b9 (annotated)

src/share/vm/services/threadService.cpp@35f8765422b9 (annotated)

src/share/vm/services/threadService.cpp

Wed, 10 Apr 2013 08:55:50 -0400

author: zgu
date: Wed, 10 Apr 2013 08:55:50 -0400
changeset 4927: 35f8765422b9
parent 4673: 5ee250974db9
child 5271: ef748153ee8f
permissions: -rw-r--r--

8010151: nsk/regression/b6653214 fails "assert(snapshot != NULL) failed: Worker should not be started"
Summary: Fixed a racing condition when shutting down NMT while worker thread is being started, also fixed a few mis-declared volatile pointers.
Reviewed-by: dholmes, dlong

 /*
  * Copyright (c) 2003, 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "classfile/systemDictionary.hpp"
 #include "memory/allocation.hpp"
 #include "memory/heapInspection.hpp"
 #include "memory/oopFactory.hpp"
 #include "oops/instanceKlass.hpp"
 #include "oops/oop.inline.hpp"
 #include "runtime/handles.inline.hpp"
 #include "runtime/init.hpp"
 #include "runtime/thread.hpp"
 #include "runtime/vframe.hpp"
 #include "runtime/vmThread.hpp"
 #include "runtime/vm_operations.hpp"
 #include "services/threadService.hpp"
 // TODO: we need to define a naming convention for perf counters
 // to distinguish counters for:
 //   - standard JSR174 use
 //   - Hotspot extension (public and committed)
 //   - Hotspot extension (private/internal and uncommitted)
 // Default is disabled.
 bool ThreadService::_thread_monitoring_contention_enabled = false;
 bool ThreadService::_thread_cpu_time_enabled = false;
 bool ThreadService::_thread_allocated_memory_enabled = false;
 PerfCounter*  ThreadService::_total_threads_count = NULL;
 PerfVariable* ThreadService::_live_threads_count = NULL;
 PerfVariable* ThreadService::_peak_threads_count = NULL;
 PerfVariable* ThreadService::_daemon_threads_count = NULL;
 volatile int ThreadService::_exiting_threads_count = 0;
 volatile int ThreadService::_exiting_daemon_threads_count = 0;
 ThreadDumpResult* ThreadService::_threaddump_list = NULL;
 static const int INITIAL_ARRAY_SIZE = 10;
 void ThreadService::init() {
   EXCEPTION_MARK;
   // These counters are for java.lang.management API support.
   // They are created even if -XX:-UsePerfData is set and in
   // that case, they will be allocated on C heap.
   _total_threads_count =
                 PerfDataManager::create_counter(JAVA_THREADS, "started",
                                                 PerfData::U_Events, CHECK);
   _live_threads_count =
                 PerfDataManager::create_variable(JAVA_THREADS, "live",
                                                  PerfData::U_None, CHECK);
   _peak_threads_count =
                 PerfDataManager::create_variable(JAVA_THREADS, "livePeak",
                                                  PerfData::U_None, CHECK);
   _daemon_threads_count =
                 PerfDataManager::create_variable(JAVA_THREADS, "daemon",
                                                  PerfData::U_None, CHECK);
   if (os::is_thread_cpu_time_supported()) {
     _thread_cpu_time_enabled = true;
   }
   _thread_allocated_memory_enabled = true; // Always on, so enable it
 }
 void ThreadService::reset_peak_thread_count() {
   // Acquire the lock to update the peak thread count
   // to synchronize with thread addition and removal.
   MutexLockerEx mu(Threads_lock);
   _peak_threads_count->set_value(get_live_thread_count());
 }
 void ThreadService::add_thread(JavaThread* thread, bool daemon) {
   // Do not count VM internal or JVMTI agent threads
   if (thread->is_hidden_from_external_view() ||
       thread->is_jvmti_agent_thread()) {
     return;
   }
   _total_threads_count->inc();
   _live_threads_count->inc();
   if (_live_threads_count->get_value() > _peak_threads_count->get_value()) {
     _peak_threads_count->set_value(_live_threads_count->get_value());
   }
   if (daemon) {
     _daemon_threads_count->inc();
   }
 }
 void ThreadService::remove_thread(JavaThread* thread, bool daemon) {
   Atomic::dec((jint*) &_exiting_threads_count);
   if (thread->is_hidden_from_external_view() ||
       thread->is_jvmti_agent_thread()) {
     return;
   }
   _live_threads_count->set_value(_live_threads_count->get_value() - 1);
   if (daemon) {
     _daemon_threads_count->set_value(_daemon_threads_count->get_value() - 1);
     Atomic::dec((jint*) &_exiting_daemon_threads_count);
   }
 }
 void ThreadService::current_thread_exiting(JavaThread* jt) {
   assert(jt == JavaThread::current(), "Called by current thread");
   Atomic::inc((jint*) &_exiting_threads_count);
   oop threadObj = jt->threadObj();
   if (threadObj != NULL && java_lang_Thread::is_daemon(threadObj)) {
     Atomic::inc((jint*) &_exiting_daemon_threads_count);
   }
 }
 // FIXME: JVMTI should call this function
 Handle ThreadService::get_current_contended_monitor(JavaThread* thread) {
   assert(thread != NULL, "should be non-NULL");
   assert(Threads_lock->owned_by_self(), "must grab Threads_lock or be at safepoint");
   ObjectMonitor *wait_obj = thread->current_waiting_monitor();
   oop obj = NULL;
   if (wait_obj != NULL) {
     // thread is doing an Object.wait() call
     obj = (oop) wait_obj->object();
     assert(obj != NULL, "Object.wait() should have an object");
   } else {
     ObjectMonitor *enter_obj = thread->current_pending_monitor();
     if (enter_obj != NULL) {
       // thread is trying to enter() or raw_enter() an ObjectMonitor.
       obj = (oop) enter_obj->object();
     }
     // If obj == NULL, then ObjectMonitor is raw which doesn't count.
   }
   Handle h(obj);
   return h;
 }
 bool ThreadService::set_thread_monitoring_contention(bool flag) {
   MutexLocker m(Management_lock);
   bool prev = _thread_monitoring_contention_enabled;
   _thread_monitoring_contention_enabled = flag;
   return prev;
 }
 bool ThreadService::set_thread_cpu_time_enabled(bool flag) {
   MutexLocker m(Management_lock);
   bool prev = _thread_cpu_time_enabled;
   _thread_cpu_time_enabled = flag;
   return prev;
 }
 bool ThreadService::set_thread_allocated_memory_enabled(bool flag) {
   MutexLocker m(Management_lock);
   bool prev = _thread_allocated_memory_enabled;
   _thread_allocated_memory_enabled = flag;
   return prev;
 }
 // GC support
 void ThreadService::oops_do(OopClosure* f) {
   for (ThreadDumpResult* dump = _threaddump_list; dump != NULL; dump = dump->next()) {
     dump->oops_do(f);
   }
 }
 void ThreadService::add_thread_dump(ThreadDumpResult* dump) {
   MutexLocker ml(Management_lock);
   if (_threaddump_list == NULL) {
     _threaddump_list = dump;
   } else {
     dump->set_next(_threaddump_list);
     _threaddump_list = dump;
   }
 }
 void ThreadService::remove_thread_dump(ThreadDumpResult* dump) {
   MutexLocker ml(Management_lock);
   ThreadDumpResult* prev = NULL;
   bool found = false;
   for (ThreadDumpResult* d = _threaddump_list; d != NULL; prev = d, d = d->next()) {
     if (d == dump) {
       if (prev == NULL) {
         _threaddump_list = dump->next();
       } else {
         prev->set_next(dump->next());
       }
       found = true;
       break;
     }
   }
   assert(found, "The threaddump result to be removed must exist.");
 }
 // Dump stack trace of threads specified in the given threads array.
 // Returns StackTraceElement[][] each element is the stack trace of a thread in
 // the corresponding entry in the given threads array
 Handle ThreadService::dump_stack_traces(GrowableArray<instanceHandle>* threads,
                                         int num_threads,
                                         TRAPS) {
   assert(num_threads > 0, "just checking");
   ThreadDumpResult dump_result;
   VM_ThreadDump op(&dump_result,
                    threads,
                    num_threads,
                    -1,    /* entire stack */
                    false, /* with locked monitors */
                    false  /* with locked synchronizers */);
   VMThread::execute(&op);
   // Allocate the resulting StackTraceElement[][] object
   ResourceMark rm(THREAD);
   Klass* k = SystemDictionary::resolve_or_fail(vmSymbols::java_lang_StackTraceElement_array(), true, CHECK_NH);
   ObjArrayKlass* ik = ObjArrayKlass::cast(k);
   objArrayOop r = oopFactory::new_objArray(ik, num_threads, CHECK_NH);
   objArrayHandle result_obj(THREAD, r);
   int num_snapshots = dump_result.num_snapshots();
   assert(num_snapshots == num_threads, "Must have num_threads thread snapshots");
   int i = 0;
   for (ThreadSnapshot* ts = dump_result.snapshots(); ts != NULL; i++, ts = ts->next()) {
     ThreadStackTrace* stacktrace = ts->get_stack_trace();
     if (stacktrace == NULL) {
       // No stack trace
       result_obj->obj_at_put(i, NULL);
     } else {
       // Construct an array of java/lang/StackTraceElement object
       Handle backtrace_h = stacktrace->allocate_fill_stack_trace_element_array(CHECK_NH);
       result_obj->obj_at_put(i, backtrace_h());
     }
   }
   return result_obj;
 }
 void ThreadService::reset_contention_count_stat(JavaThread* thread) {
   ThreadStatistics* stat = thread->get_thread_stat();
   if (stat != NULL) {
     stat->reset_count_stat();
   }
 }
 void ThreadService::reset_contention_time_stat(JavaThread* thread) {
   ThreadStatistics* stat = thread->get_thread_stat();
   if (stat != NULL) {
     stat->reset_time_stat();
   }
 }
 // Find deadlocks involving object monitors and concurrent locks if concurrent_locks is true
 DeadlockCycle* ThreadService::find_deadlocks_at_safepoint(bool concurrent_locks) {
   // This code was modified from the original Threads::find_deadlocks code.
   int globalDfn = 0, thisDfn;
   ObjectMonitor* waitingToLockMonitor = NULL;
   oop waitingToLockBlocker = NULL;
   bool blocked_on_monitor = false;
   JavaThread *currentThread, *previousThread;
   int num_deadlocks = 0;
   for (JavaThread* p = Threads::first(); p != NULL; p = p->next()) {
     // Initialize the depth-first-number
     p->set_depth_first_number(-1);
   }
   DeadlockCycle* deadlocks = NULL;
   DeadlockCycle* last = NULL;
   DeadlockCycle* cycle = new DeadlockCycle();
   for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
     if (jt->depth_first_number() >= 0) {
       // this thread was already visited
       continue;
     }
     thisDfn = globalDfn;
     jt->set_depth_first_number(globalDfn++);
     previousThread = jt;
     currentThread = jt;
     cycle->reset();
     // When there is a deadlock, all the monitors involved in the dependency
     // cycle must be contended and heavyweight. So we only care about the
     // heavyweight monitor a thread is waiting to lock.
     waitingToLockMonitor = (ObjectMonitor*)jt->current_pending_monitor();
     if (concurrent_locks) {
       waitingToLockBlocker = jt->current_park_blocker();
     }
     while (waitingToLockMonitor != NULL || waitingToLockBlocker != NULL) {
       cycle->add_thread(currentThread);
       if (waitingToLockMonitor != NULL) {
         currentThread = Threads::owning_thread_from_monitor_owner(
                           (address)waitingToLockMonitor->owner(),
                           false /* no locking needed */);
         if (currentThread == NULL) {
           // This function is called at a safepoint so the JavaThread
           // that owns waitingToLockMonitor should be findable, but
           // if it is not findable, then the previous currentThread is
           // blocked permanently. We record this as a deadlock.
           num_deadlocks++;
           cycle->set_deadlock(true);
           // add this cycle to the deadlocks list
           if (deadlocks == NULL) {
             deadlocks = cycle;
           } else {
             last->set_next(cycle);
           }
           last = cycle;
           cycle = new DeadlockCycle();
           break;
         }
       } else {
         if (concurrent_locks) {
           if (waitingToLockBlocker->is_a(SystemDictionary::abstract_ownable_synchronizer_klass())) {
             oop threadObj = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(waitingToLockBlocker);
             currentThread = threadObj != NULL ? java_lang_Thread::thread(threadObj) : NULL;
           } else {
             currentThread = NULL;
           }
         }
       }
       if (currentThread == NULL) {
         // No dependency on another thread
         break;
       }
       if (currentThread->depth_first_number() < 0) {
         // First visit to this thread
         currentThread->set_depth_first_number(globalDfn++);
       } else if (currentThread->depth_first_number() < thisDfn) {
         // Thread already visited, and not on a (new) cycle
         break;
       } else if (currentThread == previousThread) {
         // Self-loop, ignore
         break;
       } else {
         // We have a (new) cycle
         num_deadlocks++;
         cycle->set_deadlock(true);
         // add this cycle to the deadlocks list
         if (deadlocks == NULL) {
           deadlocks = cycle;
         } else {
           last->set_next(cycle);
         }
         last = cycle;
         cycle = new DeadlockCycle();
         break;
       }
       previousThread = currentThread;
       waitingToLockMonitor = (ObjectMonitor*)currentThread->current_pending_monitor();
       if (concurrent_locks) {
         waitingToLockBlocker = currentThread->current_park_blocker();
       }
     }
   }
   delete cycle;
   return deadlocks;
 }
 ThreadDumpResult::ThreadDumpResult() : _num_threads(0), _num_snapshots(0), _snapshots(NULL), _next(NULL), _last(NULL) {
   // Create a new ThreadDumpResult object and append to the list.
   // If GC happens before this function returns, Method*
   // in the stack trace will be visited.
   ThreadService::add_thread_dump(this);
 }
 ThreadDumpResult::ThreadDumpResult(int num_threads) : _num_threads(num_threads), _num_snapshots(0), _snapshots(NULL), _next(NULL), _last(NULL) {
   // Create a new ThreadDumpResult object and append to the list.
   // If GC happens before this function returns, oops
   // will be visited.
   ThreadService::add_thread_dump(this);
 }
 ThreadDumpResult::~ThreadDumpResult() {
   ThreadService::remove_thread_dump(this);
   // free all the ThreadSnapshot objects created during
   // the VM_ThreadDump operation
   ThreadSnapshot* ts = _snapshots;
   while (ts != NULL) {
     ThreadSnapshot* p = ts;
     ts = ts->next();
     delete p;
   }
 }
 void ThreadDumpResult::add_thread_snapshot(ThreadSnapshot* ts) {
   assert(_num_threads == 0 || _num_snapshots < _num_threads,
          "_num_snapshots must be less than _num_threads");
   _num_snapshots++;
   if (_snapshots == NULL) {
     _snapshots = ts;
   } else {
     _last->set_next(ts);
   }
   _last = ts;
 }
 void ThreadDumpResult::oops_do(OopClosure* f) {
   for (ThreadSnapshot* ts = _snapshots; ts != NULL; ts = ts->next()) {
     ts->oops_do(f);
   }
 }
 StackFrameInfo::StackFrameInfo(javaVFrame* jvf, bool with_lock_info) {
   _method = jvf->method();
   _bci = jvf->bci();
   _locked_monitors = NULL;
   if (with_lock_info) {
     ResourceMark rm;
     GrowableArray<MonitorInfo*>* list = jvf->locked_monitors();
     int length = list->length();
     if (length > 0) {
       _locked_monitors = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<oop>(length, true);
       for (int i = 0; i < length; i++) {
         MonitorInfo* monitor = list->at(i);
         assert(monitor->owner(), "This monitor must have an owning object");
         _locked_monitors->append(monitor->owner());
       }
     }
   }
 }
 void StackFrameInfo::oops_do(OopClosure* f) {
   if (_locked_monitors != NULL) {
     int length = _locked_monitors->length();
     for (int i = 0; i < length; i++) {
       f->do_oop((oop*) _locked_monitors->adr_at(i));
     }
   }
 }
 void StackFrameInfo::print_on(outputStream* st) const {
   ResourceMark rm;
   java_lang_Throwable::print_stack_element(st, method(), bci());
   int len = (_locked_monitors != NULL ? _locked_monitors->length() : 0);
   for (int i = 0; i < len; i++) {
     oop o = _locked_monitors->at(i);
     InstanceKlass* ik = InstanceKlass::cast(o->klass());
     st->print_cr("\t- locked <" INTPTR_FORMAT "> (a %s)", (address)o, ik->external_name());
   }
 }
 // Iterate through monitor cache to find JNI locked monitors
 class InflatedMonitorsClosure: public MonitorClosure {
 private:
   ThreadStackTrace* _stack_trace;
   Thread* _thread;
 public:
   InflatedMonitorsClosure(Thread* t, ThreadStackTrace* st) {
     _thread = t;
     _stack_trace = st;
   }
   void do_monitor(ObjectMonitor* mid) {
     if (mid->owner() == _thread) {
       oop object = (oop) mid->object();
       if (!_stack_trace->is_owned_monitor_on_stack(object)) {
         _stack_trace->add_jni_locked_monitor(object);
       }
     }
   }
 };
 ThreadStackTrace::ThreadStackTrace(JavaThread* t, bool with_locked_monitors) {
   _thread = t;
   _frames = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<StackFrameInfo*>(INITIAL_ARRAY_SIZE, true);
   _depth = 0;
   _with_locked_monitors = with_locked_monitors;
   if (_with_locked_monitors) {
     _jni_locked_monitors = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<oop>(INITIAL_ARRAY_SIZE, true);
   } else {
     _jni_locked_monitors = NULL;
   }
 }
 ThreadStackTrace::~ThreadStackTrace() {
   for (int i = 0; i < _frames->length(); i++) {
     delete _frames->at(i);
   }
   delete _frames;
   if (_jni_locked_monitors != NULL) {
     delete _jni_locked_monitors;
   }
 }
 void ThreadStackTrace::dump_stack_at_safepoint(int maxDepth) {
   assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
   if (_thread->has_last_Java_frame()) {
     RegisterMap reg_map(_thread);
     vframe* start_vf = _thread->last_java_vframe(&reg_map);
     int count = 0;
     for (vframe* f = start_vf; f; f = f->sender() ) {
       if (f->is_java_frame()) {
         javaVFrame* jvf = javaVFrame::cast(f);
         add_stack_frame(jvf);
         count++;
       } else {
         // Ignore non-Java frames
       }
       if (maxDepth > 0 && count == maxDepth) {
         // Skip frames if more than maxDepth
         break;
       }
     }
   }
   if (_with_locked_monitors) {
     // Iterate inflated monitors and find monitors locked by this thread
     // not found in the stack
     InflatedMonitorsClosure imc(_thread, this);
     ObjectSynchronizer::monitors_iterate(&imc);
   }
 }
 bool ThreadStackTrace::is_owned_monitor_on_stack(oop object) {
   assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
   bool found = false;
   int num_frames = get_stack_depth();
   for (int depth = 0; depth < num_frames; depth++) {
     StackFrameInfo* frame = stack_frame_at(depth);
     int len = frame->num_locked_monitors();
     GrowableArray<oop>* locked_monitors = frame->locked_monitors();
     for (int j = 0; j < len; j++) {
       oop monitor = locked_monitors->at(j);
       assert(monitor != NULL && monitor->is_instance(), "must be a Java object");
       if (monitor == object) {
         found = true;
         break;
       }
     }
   }
   return found;
 }
 Handle ThreadStackTrace::allocate_fill_stack_trace_element_array(TRAPS) {
   Klass* k = SystemDictionary::StackTraceElement_klass();
   assert(k != NULL, "must be loaded in 1.4+");
   instanceKlassHandle ik(THREAD, k);
   // Allocate an array of java/lang/StackTraceElement object
   objArrayOop ste = oopFactory::new_objArray(ik(), _depth, CHECK_NH);
   objArrayHandle backtrace(THREAD, ste);
   for (int j = 0; j < _depth; j++) {
     StackFrameInfo* frame = _frames->at(j);
     methodHandle mh(THREAD, frame->method());
     oop element = java_lang_StackTraceElement::create(mh, frame->bci(), CHECK_NH);
     backtrace->obj_at_put(j, element);
   }
   return backtrace;
 }
 void ThreadStackTrace::add_stack_frame(javaVFrame* jvf) {
   StackFrameInfo* frame = new StackFrameInfo(jvf, _with_locked_monitors);
   _frames->append(frame);
   _depth++;
 }
 void ThreadStackTrace::oops_do(OopClosure* f) {
   int length = _frames->length();
   for (int i = 0; i < length; i++) {
     _frames->at(i)->oops_do(f);
   }
   length = (_jni_locked_monitors != NULL ? _jni_locked_monitors->length() : 0);
   for (int j = 0; j < length; j++) {
     f->do_oop((oop*) _jni_locked_monitors->adr_at(j));
   }
 }
 ConcurrentLocksDump::~ConcurrentLocksDump() {
   if (_retain_map_on_free) {
     return;
   }
   for (ThreadConcurrentLocks* t = _map; t != NULL;)  {
     ThreadConcurrentLocks* tcl = t;
     t = t->next();
     delete tcl;
   }
 }
 void ConcurrentLocksDump::dump_at_safepoint() {
   // dump all locked concurrent locks
   assert(SafepointSynchronize::is_at_safepoint(), "all threads are stopped");
   if (JDK_Version::is_gte_jdk16x_version()) {
     ResourceMark rm;
     GrowableArray<oop>* aos_objects = new GrowableArray<oop>(INITIAL_ARRAY_SIZE);
     // Find all instances of AbstractOwnableSynchronizer
     HeapInspection::find_instances_at_safepoint(SystemDictionary::abstract_ownable_synchronizer_klass(),
                                                 aos_objects);
     // Build a map of thread to its owned AQS locks
     build_map(aos_objects);
   }
 }
 // build a map of JavaThread to all its owned AbstractOwnableSynchronizer
 void ConcurrentLocksDump::build_map(GrowableArray<oop>* aos_objects) {
   int length = aos_objects->length();
   for (int i = 0; i < length; i++) {
     oop o = aos_objects->at(i);
     oop owner_thread_obj = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(o);
     if (owner_thread_obj != NULL) {
       JavaThread* thread = java_lang_Thread::thread(owner_thread_obj);
       assert(o->is_instance(), "Must be an instanceOop");
       add_lock(thread, (instanceOop) o);
     }
   }
 }
 void ConcurrentLocksDump::add_lock(JavaThread* thread, instanceOop o) {
   ThreadConcurrentLocks* tcl = thread_concurrent_locks(thread);
   if (tcl != NULL) {
     tcl->add_lock(o);
     return;
   }
   // First owned lock found for this thread
   tcl = new ThreadConcurrentLocks(thread);
   tcl->add_lock(o);
   if (_map == NULL) {
     _map = tcl;
   } else {
     _last->set_next(tcl);
   }
   _last = tcl;
 }
 ThreadConcurrentLocks* ConcurrentLocksDump::thread_concurrent_locks(JavaThread* thread) {
   for (ThreadConcurrentLocks* tcl = _map; tcl != NULL; tcl = tcl->next()) {
     if (tcl->java_thread() == thread) {
       return tcl;
     }
   }
   return NULL;
 }
 void ConcurrentLocksDump::print_locks_on(JavaThread* t, outputStream* st) {
   st->print_cr("   Locked ownable synchronizers:");
   ThreadConcurrentLocks* tcl = thread_concurrent_locks(t);
   GrowableArray<instanceOop>* locks = (tcl != NULL ? tcl->owned_locks() : NULL);
   if (locks == NULL || locks->is_empty()) {
     st->print_cr("\t- None");
     st->cr();
     return;
   }
   for (int i = 0; i < locks->length(); i++) {
     instanceOop obj = locks->at(i);
     InstanceKlass* ik = InstanceKlass::cast(obj->klass());
     st->print_cr("\t- <" INTPTR_FORMAT "> (a %s)", (address)obj, ik->external_name());
   }
   st->cr();
 }
 ThreadConcurrentLocks::ThreadConcurrentLocks(JavaThread* thread) {
   _thread = thread;
   _owned_locks = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<instanceOop>(INITIAL_ARRAY_SIZE, true);
   _next = NULL;
 }
 ThreadConcurrentLocks::~ThreadConcurrentLocks() {
   delete _owned_locks;
 }
 void ThreadConcurrentLocks::add_lock(instanceOop o) {
   _owned_locks->append(o);
 }
 void ThreadConcurrentLocks::oops_do(OopClosure* f) {
   int length = _owned_locks->length();
   for (int i = 0; i < length; i++) {
     f->do_oop((oop*) _owned_locks->adr_at(i));
   }
 }
 ThreadStatistics::ThreadStatistics() {
   _contended_enter_count = 0;
   _monitor_wait_count = 0;
   _sleep_count = 0;
   _count_pending_reset = false;
   _timer_pending_reset = false;
   memset((void*) _perf_recursion_counts, 0, sizeof(_perf_recursion_counts));
 }
 ThreadSnapshot::ThreadSnapshot(JavaThread* thread) {
   _thread = thread;
   _threadObj = thread->threadObj();
   _stack_trace = NULL;
   _concurrent_locks = NULL;
   _next = NULL;
   ThreadStatistics* stat = thread->get_thread_stat();
   _contended_enter_ticks = stat->contended_enter_ticks();
   _contended_enter_count = stat->contended_enter_count();
   _monitor_wait_ticks = stat->monitor_wait_ticks();
   _monitor_wait_count = stat->monitor_wait_count();
   _sleep_ticks = stat->sleep_ticks();
   _sleep_count = stat->sleep_count();
   _blocker_object = NULL;
   _blocker_object_owner = NULL;
   _thread_status = java_lang_Thread::get_thread_status(_threadObj);
   _is_ext_suspended = thread->is_being_ext_suspended();
   _is_in_native = (thread->thread_state() == _thread_in_native);
   if (_thread_status == java_lang_Thread::BLOCKED_ON_MONITOR_ENTER ||
       _thread_status == java_lang_Thread::IN_OBJECT_WAIT ||
       _thread_status == java_lang_Thread::IN_OBJECT_WAIT_TIMED) {
     Handle obj = ThreadService::get_current_contended_monitor(thread);
     if (obj() == NULL) {
       // monitor no longer exists; thread is not blocked
       _thread_status = java_lang_Thread::RUNNABLE;
     } else {
       _blocker_object = obj();
       JavaThread* owner = ObjectSynchronizer::get_lock_owner(obj, false);
       if ((owner == NULL && _thread_status == java_lang_Thread::BLOCKED_ON_MONITOR_ENTER)
           || (owner != NULL && owner->is_attaching_via_jni())) {
         // ownership information of the monitor is not available
         // (may no longer be owned or releasing to some other thread)
         // make this thread in RUNNABLE state.
         // And when the owner thread is in attaching state, the java thread
         // is not completely initialized. For example thread name and id
         // and may not be set, so hide the attaching thread.
         _thread_status = java_lang_Thread::RUNNABLE;
         _blocker_object = NULL;
       } else if (owner != NULL) {
         _blocker_object_owner = owner->threadObj();
       }
     }
   }
   // Support for JSR-166 locks
   if (JDK_Version::current().supports_thread_park_blocker() &&
         (_thread_status == java_lang_Thread::PARKED ||
          _thread_status == java_lang_Thread::PARKED_TIMED)) {
     _blocker_object = thread->current_park_blocker();
     if (_blocker_object != NULL && _blocker_object->is_a(SystemDictionary::abstract_ownable_synchronizer_klass())) {
       _blocker_object_owner = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(_blocker_object);
     }
   }
 }
 ThreadSnapshot::~ThreadSnapshot() {
   delete _stack_trace;
   delete _concurrent_locks;
 }
 void ThreadSnapshot::dump_stack_at_safepoint(int max_depth, bool with_locked_monitors) {
   _stack_trace = new ThreadStackTrace(_thread, with_locked_monitors);
   _stack_trace->dump_stack_at_safepoint(max_depth);
 }
 void ThreadSnapshot::oops_do(OopClosure* f) {
   f->do_oop(&_threadObj);
   f->do_oop(&_blocker_object);
   f->do_oop(&_blocker_object_owner);
   if (_stack_trace != NULL) {
     _stack_trace->oops_do(f);
   }
   if (_concurrent_locks != NULL) {
     _concurrent_locks->oops_do(f);
   }
 }
 DeadlockCycle::DeadlockCycle() {
   _is_deadlock = false;
   _threads = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<JavaThread*>(INITIAL_ARRAY_SIZE, true);
   _next = NULL;
 }
 DeadlockCycle::~DeadlockCycle() {
   delete _threads;
 }
 void DeadlockCycle::print_on(outputStream* st) const {
   st->cr();
   st->print_cr("Found one Java-level deadlock:");
   st->print("=============================");
   JavaThread* currentThread;
   ObjectMonitor* waitingToLockMonitor;
   oop waitingToLockBlocker;
   int len = _threads->length();
   for (int i = 0; i < len; i++) {
     currentThread = _threads->at(i);
     waitingToLockMonitor = (ObjectMonitor*)currentThread->current_pending_monitor();
     waitingToLockBlocker = currentThread->current_park_blocker();
     st->cr();
     st->print_cr("\"%s\":", currentThread->get_thread_name());
     const char* owner_desc = ",\n  which is held by";
     if (waitingToLockMonitor != NULL) {
       st->print("  waiting to lock monitor " INTPTR_FORMAT, waitingToLockMonitor);
       oop obj = (oop)waitingToLockMonitor->object();
       if (obj != NULL) {
         st->print(" (object "INTPTR_FORMAT ", a %s)", (address)obj,
                    (InstanceKlass::cast(obj->klass()))->external_name());
         if (!currentThread->current_pending_monitor_is_from_java()) {
           owner_desc = "\n  in JNI, which is held by";
         }
       } else {
         // No Java object associated - a JVMTI raw monitor
         owner_desc = " (JVMTI raw monitor),\n  which is held by";
       }
       currentThread = Threads::owning_thread_from_monitor_owner(
                         (address)waitingToLockMonitor->owner(),
                         false /* no locking needed */);
       if (currentThread == NULL) {
         // The deadlock was detected at a safepoint so the JavaThread
         // that owns waitingToLockMonitor should be findable, but
         // if it is not findable, then the previous currentThread is
         // blocked permanently.
         st->print("%s UNKNOWN_owner_addr=" PTR_FORMAT, owner_desc,
                   (address)waitingToLockMonitor->owner());
         continue;
       }
     } else {
       st->print("  waiting for ownable synchronizer " INTPTR_FORMAT ", (a %s)",
                 (address)waitingToLockBlocker,
                 (InstanceKlass::cast(waitingToLockBlocker->klass()))->external_name());
       assert(waitingToLockBlocker->is_a(SystemDictionary::abstract_ownable_synchronizer_klass()),
              "Must be an AbstractOwnableSynchronizer");
       oop ownerObj = java_util_concurrent_locks_AbstractOwnableSynchronizer::get_owner_threadObj(waitingToLockBlocker);
       currentThread = java_lang_Thread::thread(ownerObj);
     }
     st->print("%s \"%s\"", owner_desc, currentThread->get_thread_name());
   }
   st->cr();
   st->cr();
   // Print stack traces
   bool oldJavaMonitorsInStackTrace = JavaMonitorsInStackTrace;
   JavaMonitorsInStackTrace = true;
   st->print_cr("Java stack information for the threads listed above:");
   st->print_cr("===================================================");
   for (int j = 0; j < len; j++) {
     currentThread = _threads->at(j);
     st->print_cr("\"%s\":", currentThread->get_thread_name());
     currentThread->print_stack_on(st);
   }
   JavaMonitorsInStackTrace = oldJavaMonitorsInStackTrace;
 }
 ThreadsListEnumerator::ThreadsListEnumerator(Thread* cur_thread,
                                              bool include_jvmti_agent_threads,
                                              bool include_jni_attaching_threads) {
   assert(cur_thread == Thread::current(), "Check current thread");
   int init_size = ThreadService::get_live_thread_count();
   _threads_array = new GrowableArray<instanceHandle>(init_size);
   MutexLockerEx ml(Threads_lock);
   for (JavaThread* jt = Threads::first(); jt != NULL; jt = jt->next()) {
     // skips JavaThreads in the process of exiting
     // and also skips VM internal JavaThreads
     // Threads in _thread_new or _thread_new_trans state are included.
     // i.e. threads have been started but not yet running.
     if (jt->threadObj() == NULL   ||
         jt->is_exiting() ||
         !java_lang_Thread::is_alive(jt->threadObj())   ||
         jt->is_hidden_from_external_view()) {
       continue;
     }
     // skip agent threads
     if (!include_jvmti_agent_threads && jt->is_jvmti_agent_thread()) {
       continue;
     }
     // skip jni threads in the process of attaching
     if (!include_jni_attaching_threads && jt->is_attaching_via_jni()) {
       continue;
     }
     instanceHandle h(cur_thread, (instanceOop) jt->threadObj());
     _threads_array->append(h);
   }
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/services/threadService.cpp@35f8765422b9 (annotated)

src/share/vm/services/threadService.cpp