src/share/vm/services/threadService.cpp

*** 1,7 ****
  /*
!  * Copyright (c) 2003, 2012, 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.
--- 1,7 ----
  /*
!  * 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.
*** 325,337 ****
        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 */);
        } 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 {
--- 325,357 ----
        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 {
*** 839,849 ****
        } 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 */);
      } 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()),
--- 859,879 ----
        } 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()),