src/hotspot/share/jfr/recorder/repository/jfrEmergencyDump.cpp

@@ -330,37 +330,31 @@
   }
 }
 
 /*
 * We are just about to exit the VM, so we will be very aggressive
-* at this point in order to increase overall success of dumping jfr data:
-*
-* 1. if the thread state is not "_thread_in_vm", we will quick transition
-*    it to "_thread_in_vm".
-* 2. if the thread is the owner of some critical lock(s), unlock them.
+* at this point in order to increase overall success of dumping jfr data.
 *
 * If we end up deadlocking in the attempt of dumping out jfr data,
 * we rely on the WatcherThread task "is_error_reported()",
 * to exit the VM after a hard-coded timeout (disallow WatcherThread to emergency dump).
 * This "safety net" somewhat explains the aggressiveness in this attempt.
 *
 */
 static bool prepare_for_emergency_dump() {
+  Thread* const thread = Thread::current_or_null_safe();
+  assert(thread != NULL, "invariant");
+
   if (JfrStream_lock->owned_by_self()) {
     // crashed during jfr rotation, disallow recursion
     return false;
   }
-  Thread* const thread = Thread::current();
   if (thread->is_Watcher_thread()) {
     // need WatcherThread as a safeguard against potential deadlocks
     return false;
   }
 
-  if (thread->is_Java_thread()) {
-    ((JavaThread*)thread)->set_thread_state(_thread_in_vm);
-  }
-
 #ifdef ASSERT
   Mutex* owned_lock = thread->owned_locks();
   while (owned_lock != NULL) {
     Mutex* next = owned_lock->next();
     owned_lock->unlock();

@@ -426,14 +420,47 @@
 
 static bool guard_reentrancy() {
   return Atomic::cmpxchg(1, &jfr_shutdown_lock, 0) == 0;
 }
 
+class JavaThreadInVM : public StackObj {
+ private:
+  JavaThread* _jt;
+  JavaThreadState _original_state;
+
+ public:
+
+  JavaThreadInVM(Thread* thread) : _jt(NULL),
+                                   _original_state(_thread_max_state) {
+    if ((thread != NULL) && thread->is_Java_thread()) {
+      _jt = (JavaThread*)thread;
+      _original_state = _jt->thread_state();
+      _jt->set_thread_state(_thread_in_vm);
+    }
+  }
+
+  ~JavaThreadInVM() {
+    if (_jt != NULL) {
+      _jt->set_thread_state(_original_state);
+    }
+  }
+
+};
+
 void JfrEmergencyDump::on_vm_shutdown(bool exception_handler) {
-  if (!(guard_reentrancy() && prepare_for_emergency_dump())) {
+  if (!guard_reentrancy()) {
     return;
   }
+
+  Thread* thread = Thread::current_or_null_safe();
+
+  // Ensure a JavaThread is _thread_in_vm when we make this call
+  JavaThreadInVM jtivm(thread);
+  if ((thread != NULL) && !prepare_for_emergency_dump()) {
+    return;
+  }
+
   EventDumpReason event;
   if (event.should_commit()) {
     event.set_reason(exception_handler ? "Crash" : "Out of Memory");
     event.set_recordingId(-1);
     event.commit();