8316397: StackTrace/Suspended/GetStackTraceSuspendedStressTest.java failed with: SingleStep event is NOT expected

Reviewed-by: dholmes, pchilanomate

Author: Serguei Spitsyn

src/hotspot/share/prims/jvmtiExport.cpp

@@ -418,10 +418,16 @@ JvmtiExport::get_jvmti_interface(JavaVM *jvm, void **penv, jint version) {
 }
 
 JvmtiThreadState*
-JvmtiExport::get_jvmti_thread_state(JavaThread *thread) {
+JvmtiExport::get_jvmti_thread_state(JavaThread *thread, bool allow_suspend) {
   assert(thread == JavaThread::current(), "must be current thread");
   if (thread->is_vthread_mounted() && thread->jvmti_thread_state() == nullptr) {
     JvmtiEventController::thread_started(thread);
+    if (allow_suspend && thread->is_suspended()) {
+      // Suspend here if thread_started got a suspend request during its execution.
+      // Within thread_started we could block on a VM mutex and pick up a suspend
+      // request from debug agent which we need to honor before proceeding.
+      ThreadBlockInVM tbivm(thread, true /* allow suspend */);
+    }
   }
   return thread->jvmti_thread_state();
 }
@@ -2636,7 +2642,7 @@ void JvmtiExport::post_dynamic_code_generated_while_holding_locks(const char* na
   // jvmti thread state.
   // The collector and/or state might be null if JvmtiDynamicCodeEventCollector
   // has been initialized while JVMTI_EVENT_DYNAMIC_CODE_GENERATED was disabled.
-  JvmtiThreadState *state = get_jvmti_thread_state(thread);
+  JvmtiThreadState *state = get_jvmti_thread_state(thread, false /* allow_suspend */);
   if (state != nullptr) {
     JvmtiDynamicCodeEventCollector *collector = state->get_dynamic_code_event_collector();
     if (collector != nullptr) {

src/hotspot/share/prims/jvmtiExport.hpp

@@ -309,7 +309,11 @@ class JvmtiExport : public AllStatic {
   // If the jvmti_thread_state is absent and any thread filtered event
   // is enabled globally then it is created.
   // Otherwise, the thread->jvmti_thread_state() is returned.
-  static JvmtiThreadState* get_jvmti_thread_state(JavaThread *thread);
+  // The 'allow_suspend' parameter is passed as 'true' by default which work for almost all call sites.
+  // It means that a suspend point need to be organized by this function for virtual threads if the call
+  // to jvmtiEventController::thread_started hits a safepoint and gets a new suspend request.
+  // The 'allow_suspend' parameter must be passed as 'false' if thread is holding a VM lock.
+  static JvmtiThreadState* get_jvmti_thread_state(JavaThread *thread, bool allow_suspend = true);
 
   // single stepping management methods
   static void at_single_stepping_point(JavaThread *thread, Method* method, address location) NOT_JVMTI_RETURN;