Use JvmtiVTMSTransitionDisabler::VTMS_vthread_mount/unmount

Author: pchilano

src/hotspot/share/prims/jvmtiThreadState.cpp

@@ -667,12 +667,6 @@ JvmtiVTMSTransitionDisabler::VTMS_unmount_end(jobject vthread) {
   JavaThread* thread = JavaThread::current();
   assert(thread->is_in_VTMS_transition(), "sanity check");
   finish_VTMS_transition(vthread, /* is_mount */ false);
-
-  if (thread->pending_jvmti_unmount_event()) {
-    assert(java_lang_VirtualThread::is_preempted(JNIHandles::resolve(vthread)), "should be marked preempted");
-    JvmtiExport::post_vthread_unmount(vthread);
-    thread->set_pending_jvmti_unmount_event(false);
-  }
 }
 
 

src/hotspot/share/runtime/continuation.cpp

@@ -70,7 +70,7 @@ class JvmtiUnmountBeginMark : public StackObj {
     assert(!_target->is_in_VTMS_transition(), "must be");
 
     if (JvmtiVTMSTransitionDisabler::VTMS_notify_jvmti_events()) {
-      JvmtiVTMSTransitionDisabler::start_VTMS_transition((jthread)_vthread.raw_value(), /* is_mount */ false);
+      JvmtiVTMSTransitionDisabler::VTMS_vthread_unmount((jthread)_vthread.raw_value(), true);
 
       // Don't preempt if there is a pending popframe or earlyret operation. This can
       // be installed in start_VTMS_transition() so we need to check it here.
@@ -104,20 +104,11 @@ class JvmtiUnmountBeginMark : public StackObj {
     if (_result != freeze_ok) {
       // Undo transition
       if (jvmti_present) {
-        JvmtiVTMSTransitionDisabler::finish_VTMS_transition((jthread)_vthread.raw_value(), false);
+        JvmtiVTMSTransitionDisabler::VTMS_vthread_mount((jthread)_vthread.raw_value(), false);
       } else {
         _target->set_is_in_VTMS_transition(false);
         java_lang_Thread::set_is_in_VTMS_transition(_vthread(), false);
       }
-    } else {
-      if (jvmti_present) {
-        _target->rebind_to_jvmti_thread_state_of(_target->threadObj());
-        if (JvmtiExport::should_post_vthread_unmount()) {
-          // We are inside the VTMS transition already so we will post the event
-          // once we finish it in JvmtiVTMSTransitionDisabler::VTMS_unmount_end().
-          _target->set_pending_jvmti_unmount_event(true);
-        }
-      }
     }
   }
   void set_result(freeze_result res) { _result = res; }

src/hotspot/share/runtime/continuationFreezeThaw.cpp

@@ -1608,17 +1608,7 @@ static void jvmti_mount_end(JavaThread* current, ContinuationWrapper& cont, fram
   set_anchor(current, top.sp());
 
   JRT_BLOCK
-    current->rebind_to_jvmti_thread_state_of(vth());
-    JvmtiVTMSTransitionDisabler::finish_VTMS_transition((jthread)vth.raw_value(), /* is_mount */ true);
-
-    // If pending_jvmti_unmount_event() is true here we are in the preemption
-    // cancelled case. Since we never unmounted we don't post the mount event
-    // and just clear the pending unmount flag.
-    if (current->pending_jvmti_unmount_event()) {
-      current->set_pending_jvmti_unmount_event(false);
-    } else if (JvmtiExport::should_post_vthread_mount()) {
-      JvmtiExport::post_vthread_mount((jthread)vth.raw_value());
-    }
+    JvmtiVTMSTransitionDisabler::VTMS_vthread_mount((jthread)vth.raw_value(), false);
 
     if (current->pending_contended_entered_event()) {
       JvmtiExport::post_monitor_contended_entered(current, current->contended_entered_monitor());

src/hotspot/share/runtime/javaThread.cpp

@@ -455,7 +455,6 @@ JavaThread::JavaThread(MemTag mem_tag) :
   _is_in_VTMS_transition(false),
   _is_disable_suspend(false),
   _VTMS_transition_mark(false),
-  _pending_jvmti_unmount_event(false),
   _on_monitor_waited_event(false),
   _contended_entered_monitor(nullptr),
 #ifdef ASSERT

src/hotspot/share/runtime/javaThread.hpp

@@ -328,7 +328,6 @@ class JavaThread: public Thread {
   bool                  _is_in_VTMS_transition;          // thread is in virtual thread mount state transition
   bool                  _is_disable_suspend;             // JVMTI suspend is temporarily disabled; used on current thread only
   bool                  _VTMS_transition_mark;           // used for sync between VTMS transitions and disablers
-  bool                  _pending_jvmti_unmount_event;    // When preempting we post unmount event at unmount end rather than start
   bool                  _on_monitor_waited_event;        // Avoid callee arg processing for enterSpecial when posting waited event
   ObjectMonitor*        _contended_entered_monitor;      // Monitor for pending monitor_contended_entered callback
 #ifdef ASSERT
@@ -722,9 +721,6 @@ class JavaThread: public Thread {
   bool VTMS_transition_mark() const              { return Atomic::load(&_VTMS_transition_mark); }
   void set_VTMS_transition_mark(bool val)        { Atomic::store(&_VTMS_transition_mark, val); }
 
-  bool pending_jvmti_unmount_event()             { return _pending_jvmti_unmount_event; }
-  void set_pending_jvmti_unmount_event(bool val) { _pending_jvmti_unmount_event = val; }
-
   bool on_monitor_waited_event()             { return _on_monitor_waited_event; }
   void set_on_monitor_waited_event(bool val) { _on_monitor_waited_event = val; }