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src/hotspot/share/jfr/recorder/repository/jfrEmergencyDump.cpp
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@@ -332,12 +332,11 @@
/*
* 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".
+* 1. if current thread is JavaThread, thread state need to be set to "_thread_in_vm".
* 2. if the thread is the owner of some critical lock(s), unlock them.
*
* 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).
@@ -353,13 +352,11 @@
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);
- }
+ assert(thread->is_Java_thread() && (((JavaThread*)thread)->thread_state() == _thread_in_vm), "invariant");
#ifdef ASSERT
Mutex* owned_lock = thread->owned_locks();
while (owned_lock != NULL) {
Mutex* next = owned_lock->next();
@@ -426,11 +423,41 @@
static bool guard_reentrancy() {
return Atomic::cmpxchg(1, &jfr_shutdown_lock, 0) == 0;
}
-void JfrEmergencyDump::on_vm_shutdown(bool exception_handler) {
+class ThreadInVMForJFR : public StackObj {
+ private:
+ JavaThread* _jt;
+ JavaThreadState _original_state;
+
+ public:
+
+ ThreadInVMForJFR(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);
+ }
+ }
+
+ ~ThreadInVMForJFR() {
+ if (_jt != NULL) {
+ _jt->set_thread_state(_original_state);
+ }
+ }
+
+};
+
+void JfrEmergencyDump::on_vm_shutdown(Thread* thread, bool exception_handler) {
+ /*
+ * if the thread state is not "_thread_in_vm", we will quick transition
+ * it to "_thread_in_vm" via ThreadInVMForJFR.
+ */
+ ThreadInVMForJFR tiv(thread);
+
if (!(guard_reentrancy() && prepare_for_emergency_dump())) {
return;
}
EventDumpReason event;
if (event.should_commit()) {
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