Merge pull request #16501 from dipak-bagadiya/jvmti-MountUnmout-fix

Add JVMTI VirtualThread Mount and Unmount Events

runtime/include/ibmjvmti.h

@@ -103,6 +103,9 @@
 #define COM_SUN_HOTSPOT_FUNCTIONS_GET_VIRTUAL_THREAD "com.sun.hotspot.functions.GetVirtualThread"
 #define COM_SUN_HOTSPOT_FUNCTIONS_GET_CARRIER_THREAD "com.sun.hotspot.functions.GetCarrierThread"
 
+#define COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT "com.sun.hotspot.events.VirtualThreadMount"
+#define COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT "com.sun.hotspot.events.VirtualThreadUnmount"
+
 #define COM_IBM_SHARED_CACHE_MODLEVEL_JAVA5 1
 #define COM_IBM_SHARED_CACHE_MODLEVEL_JAVA6 2
 #define COM_IBM_SHARED_CACHE_MODLEVEL_JAVA7 3

runtime/j9vm/javanextvmi.cpp

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 2018, 2022 IBM Corp. and others
+ * Copyright (c) 2018, 2023 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -390,6 +390,7 @@ JVM_VirtualThreadMountEnd(JNIEnv *env, jobject thread, jboolean firstMount)
 
 		TRIGGER_J9HOOK_VM_VIRTUAL_THREAD_STARTED(vm->hookInterface, currentThread);
 	}
+	TRIGGER_J9HOOK_VM_VIRTUAL_THREAD_MOUNT(vm->hookInterface, currentThread);
 
 	/* Allow thread to be inspected again. */
 	Assert_SC_true(-1 == J9OBJECT_I64_LOAD(currentThread, threadObj, vm->virtualThreadInspectorCountOffset));
@@ -460,6 +461,7 @@ JVM_VirtualThreadUnmountBegin(JNIEnv *env, jobject thread, jboolean lastUnmount)
 	 */
 	J9OBJECT_I64_STORE(currentThread, threadObj, vm->virtualThreadInspectorCountOffset, -1);
 
+	TRIGGER_J9HOOK_VM_VIRTUAL_THREAD_UNMOUNT(vm->hookInterface, currentThread);
 	if (lastUnmount) {
 		if (NULL != vm->liveVirtualThreadList) {
 			j9object_t threadPrev = J9OBJECT_OBJECT_LOAD(currentThread, threadObj, vm->virtualThreadLinkPreviousOffset);

runtime/jvmti/j9jvmti.tdf

@@ -652,3 +652,9 @@ TraceEntry=Trc_JVMTI_jvmtiGetVirtualThread_Exit Overhead=1 Level=1 Noenv Templat
 
 TraceEntry=Trc_JVMTI_jvmtiGetCarrierThread_Entry Overhead=1 Level=1 Noenv Template="GetCarrierThread env=%p"
 TraceEntry=Trc_JVMTI_jvmtiGetCarrierThread_Exit Overhead=1 Level=1 Noenv Template="GetCarrierThread returning %d"
+
+TraceEntry=Trc_JVMTI_jvmtiHookVirtualThreadUnmount_Entry Overhead=1 Level=5 Noenv Template="HookVirtualThreadUnmount"
+TraceExit=Trc_JVMTI_jvmtiHookVirtualThreadUnmount_Exit Overhead=1 Level=5 Noenv Template="HookVirtualThreadUnmount"
+
+TraceEntry=Trc_JVMTI_jvmtiHookVirtualThreadMount_Entry Overhead=1 Level=5 Noenv Template="HookVirtualThreadMount"
+TraceExit=Trc_JVMTI_jvmtiHookVirtualThreadMount_Exit Overhead=1 Level=5 Noenv Template="HookVirtualThreadMount"

runtime/jvmti/jvmtiEventManagement.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 1991, 2022 IBM Corp. and others
+ * Copyright (c) 1991, 2023 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -100,7 +100,7 @@ jvmtiSetEventNotificationMode(jvmtiEnv* env,
 		/* Ensure the required capabilities are enabled for the event if the event is being enabled */
 
 		if (mode == JVMTI_ENABLE) {
-			switch(event_type) {
+			switch((int)event_type) {
 				case JVMTI_EVENT_FIELD_MODIFICATION:
 					ENSURE_CAPABILITY(env, can_generate_field_modification_events);
 					break;
@@ -159,6 +159,8 @@ jvmtiSetEventNotificationMode(jvmtiEnv* env,
 #if JAVA_SPEC_VERSION >= 19
 				case JVMTI_EVENT_VIRTUAL_THREAD_START:
 				case JVMTI_EVENT_VIRTUAL_THREAD_END:
+				case J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT:
+				case J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT:
 					ENSURE_CAPABILITY(env, can_support_virtual_threads);
 					break;
 #endif /* JAVA_SPEC_VERSION >= 19 */

runtime/jvmti/jvmtiExtensionMechanism.c

@@ -350,6 +350,18 @@ static const jvmtiParamInfo jvmtiRegisterTracePointSubscriber_params[] = {
 static const jvmtiParamInfo jvmtiDeregisterTracepointSubscriber_params[] = {
 	{ "subscriptionID", JVMTI_KIND_IN_PTR, JVMTI_TYPE_CVOID, JNI_FALSE }
 };
+#if JAVA_SPEC_VERSION >= 19
+/* (jvmtiEnv *jvmti_env, jthread thread) */
+static const jvmtiParamInfo jvmtiVirtualThreadMount_params[] = {
+	{ "jni_env", JVMTI_KIND_IN_PTR, JVMTI_TYPE_JNIENV, JNI_FALSE },
+	{ "thread", JVMTI_KIND_IN, JVMTI_TYPE_JTHREAD, JNI_FALSE }
+};
+
+static const jvmtiParamInfo jvmtiVirtualThreadUnmount_params[] = {
+	{ "jni_env", JVMTI_KIND_IN_PTR, JVMTI_TYPE_JNIENV, JNI_FALSE },
+	{ "thread", JVMTI_KIND_IN, JVMTI_TYPE_JTHREAD, JNI_FALSE }
+};
+#endif /* JAVA_SPEC_VERSION >= 19 */
 
 #if JAVA_SPEC_VERSION >= 19
 /* (jvmtiEnv *jvmti_env, jthread carrier_thread, jthread *virtual_thread_ptr) */
@@ -824,6 +836,20 @@ static const J9JVMTIExtensionEventInfo J9JVMTIExtensionEventInfoTable[] = {
 		J9NLS_JVMTI_COM_IBM_GARBAGE_COLLECTION_CYCLE_FINISH_DESCRIPTION,
 		EMPTY_SIZE_AND_TABLE,
 	},
+#if JAVA_SPEC_VERSION >= 19
+	{
+		J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT,
+		COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT,
+		J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT,
+		SIZE_AND_TABLE(jvmtiVirtualThreadMount_params),
+	},
+	{
+		J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT,
+		COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT,
+		J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT,
+		SIZE_AND_TABLE(jvmtiVirtualThreadUnmount_params),
+	},
+#endif /* JAVA_SPEC_VERSION >= 19 */
 };
 
 #define NUM_EXTENSION_EVENTS (sizeof(J9JVMTIExtensionEventInfoTable) / sizeof(J9JVMTIExtensionEventInfoTable[0]))

runtime/jvmti/jvmtiHelpers.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 1991, 2022 IBM Corp. and others
+ * Copyright (c) 1991, 2023 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -75,6 +75,8 @@ static const UDATA reasonCodeFromJVMTIEvent[] = {
 	J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VM_DUMP_END,							/* J9JVMTI_EVENT_COM_IBM_VM_DUMP_END */
 	J9_JNI_OFFLOAD_SWITCH_J9JVMTI_GC_CYCLE_START,						/* J9JVMTI_EVENT_COM_IBM_GARBAGE_COLLECTION_CYCLE_START */
 	J9_JNI_OFFLOAD_SWITCH_J9JVMTI_GC_CYCLE_FINISH,						/* J9JVMTI_EVENT_COM_IBM_GARBAGE_COLLECTION_CYCLE_FINISH */
+	J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VIRTUAL_THREAD_MOUNT,					/* J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT */
+	J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VIRTUAL_THREAD_UNMOUNT,					/* J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT */
 };
 #endif /* J9VM_OPT_JAVA_OFFLOAD_SUPPORT */
 

runtime/jvmti/jvmtiHook.c

@@ -1,5 +1,5 @@
 /*******************************************************************************
- * Copyright (c) 1991, 2022 IBM Corp. and others
+ * Copyright (c) 1991, 2023 IBM Corp. and others
  *
  * This program and the accompanying materials are made available under
  * the terms of the Eclipse Public License 2.0 which accompanies this
@@ -148,6 +148,8 @@ static UDATA methodExists(J9Class * methodClass, U_8 * nameData, UDATA nameLengt
 static void jvmtiHookVirtualThreadStarted (J9HookInterface** hook, UDATA eventNum, void* eventData, void* userData);
 static void jvmtiHookVirtualThreadEnd (J9HookInterface** hook, UDATA eventNum, void* eventData, void* userData);
 static void jvmtiHookVirtualThreadDestroy (J9HookInterface **hook, UDATA eventNum, void *eventData, void *userData);
+static void jvmtiHookVirtualThreadMount (J9HookInterface** hook, UDATA eventNum, void* eventData, void* userData);
+static void jvmtiHookVirtualThreadUnmount (J9HookInterface** hook, UDATA eventNum, void* eventData, void* userData);
 #endif /* JAVA_SPEC_VERSION >= 19 */
 
 static void
@@ -421,6 +423,86 @@ jvmtiHookVirtualThreadDestroy(J9HookInterface **hook, UDATA eventNum, void *even
 
 	TRACE_JVMTI_EVENT_RETURN(jvmtiHookVirtualThreadDestroy);
 }
+
+/**
+ * Virtual thread mount event.
+ *
+ * @param hook Hook interface used by the JVM.
+ * @param eventNum The hook event number
+ * @param eventData hook specific event data.
+ * @param userData pointer to J9VMRuntimeStateListener
+ * @return void.
+ */
+static void
+jvmtiHookVirtualThreadMount(J9HookInterface **hook, UDATA eventNum, void *eventData, void *userData)
+{
+	J9VMVirtualThreadMountEvent *data = eventData;
+	J9JVMTIEnv *j9env = userData;
+	J9VMThread *currentThread = data->currentThread;
+	jvmtiExtensionEvent callback = *J9JVMTI_EXTENSION_CALLBACK(j9env, J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT);
+
+	Trc_JVMTI_jvmtiHookVirtualThreadMount_Entry();
+
+	ENSURE_EVENT_PHASE_LIVE(jvmtiHookVirtualThreadMount, j9env);
+
+	/* Call the event callback */
+
+	if (NULL != callback) {
+		jthread threadRef = NULL;
+		UDATA hadVMAccess = 0;
+		UDATA javaOffloadOldState = 0;
+		if (prepareForEvent(
+			j9env, currentThread, currentThread, J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT,
+			&threadRef, &hadVMAccess, TRUE, 0, &javaOffloadOldState)
+		) {
+			callback((jvmtiEnv *)j9env, (JNIEnv *)currentThread, threadRef);
+			finishedEvent(currentThread, J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT, hadVMAccess, javaOffloadOldState);
+		}
+	}
+
+	TRACE_JVMTI_EVENT_RETURN(jvmtiHookVirtualThreadMount);
+}
+
+/**
+ * Virtual thread unmount event.
+ *
+ * @param hook Hook interface used by the JVM.
+ * @param eventNum The hook event number
+ * @param eventData hook specific event data.
+ * @param userData pointer to J9VMRuntimeStateListener
+ * @return void.
+ */
+static void
+jvmtiHookVirtualThreadUnmount(J9HookInterface **hook, UDATA eventNum, void *eventData, void *userData)
+{
+	J9VMVirtualThreadUnmountEvent *data = eventData;
+	J9JVMTIEnv *j9env = userData;
+	jvmtiExtensionEvent callback = *J9JVMTI_EXTENSION_CALLBACK(j9env, J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT);
+	J9VMThread *currentThread = data->currentThread;
+
+	Trc_JVMTI_jvmtiHookVirtualThreadUnmount_Entry();
+
+	ENSURE_EVENT_PHASE_LIVE(jvmtiHookVirtualThreadUnmount, j9env);
+
+	/* Call the event callback */
+
+	if (NULL != callback) {
+		jthread threadRef = NULL;
+		UDATA hadVMAccess = 0;
+		UDATA javaOffloadOldState = 0;
+
+		if (prepareForEvent(
+			j9env, currentThread, currentThread, J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT,
+			&threadRef, &hadVMAccess, TRUE, 0, &javaOffloadOldState)
+		) {
+			callback((jvmtiEnv *)j9env, (JNIEnv *)currentThread, threadRef);
+			finishedEvent(data->currentThread, J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT, hadVMAccess, javaOffloadOldState);
+		}
+	}
+
+	TRACE_JVMTI_EVENT_RETURN(jvmtiHookVirtualThreadUnmount);
+}
+
 #endif /* JAVA_SPEC_VERSION >= 19 */
 
 static IDATA
@@ -618,6 +700,14 @@ processEvent(J9JVMTIEnv* j9env, jint event, J9HookRedirectorFunction redirectorF
 			} else {
 				return 0;
 			}
+#if JAVA_SPEC_VERSION >= 19
+		case J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT:
+			return redirectorFunction(vmHook, J9HOOK_VM_VIRTUAL_THREAD_MOUNT, jvmtiHookVirtualThreadMount, OMR_GET_CALLSITE(), j9env);
+
+		case J9JVMTI_EVENT_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT:
+			return redirectorFunction(vmHook, J9HOOK_VM_VIRTUAL_THREAD_UNMOUNT, jvmtiHookVirtualThreadUnmount, OMR_GET_CALLSITE(), j9env);
+#endif /* JAVA_SPEC_VERSION >= 19 */
+
 	}
 
 	return 0;

runtime/nls/j9ti/jvmti.nls

@@ -624,3 +624,17 @@ J9NLS_JVMTI_COM_SUN_HOTSPOT_FUNCTIONS_GET_CARRIER_THREAD.explanation=Internation
 J9NLS_JVMTI_COM_SUN_HOTSPOT_FUNCTIONS_GET_CARRIER_THREAD.system_action=None
 J9NLS_JVMTI_COM_SUN_HOTSPOT_FUNCTIONS_GET_CARRIER_THREAD.user_response=None
 # END NON-TRANSLATABLE
+
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT=Report a virtual thread mount.
+# START NON-TRANSLATABLE
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT.explanation=Internationalized description of a JVMTI extension
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT.system_action=None
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_MOUNT.user_response=None
+# END NON-TRANSLATABLE
+
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT=Report a virtual thread unmount.
+# START NON-TRANSLATABLE
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT.explanation=Internationalized description of a JVMTI extension
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT.system_action=None
+J9NLS_JVMTI_COM_SUN_HOTSPOT_EVENTS_VIRTUAL_THREAD_UNMOUNT.user_response=None
+# END NON-TRANSLATABLE

runtime/oti/j9consts.h

@@ -741,51 +741,51 @@ extern "C" {
 /* Jazz 99339: The reason code for JVMTI event callbacks on zOS.
  * Note: refer to jvmtiEventCallbacks (/runtime/include/jvmti.h) for reserved JVMTI events.
  */
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_INIT								0x16
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_DEATH							0x17
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_THREAD_START						0x18
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_THREAD_END							0x19
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_CLASS_FILE_LOAD_HOOK				0x1A
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_CLASS_LOAD							0x1B
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_CLASS_PREPARE						0x1C
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_START							0x1D
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_EXCEPTION							0x1E
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_EXCEPTION_CATCH						0x1F
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_SINGLE_STEP							0x20
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_FRAME_POP							0x21
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_BREAKPOINT							0x22
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_FIELD_ACCESS						0x23
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_FIELD_MODIFICATION					0x24
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_METHOD_ENTRY						0x25
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_METHOD_EXIT							0x26
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_NATIVE_METHOD_BIND					0x27
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_COMPILED_METHOD_LOAD				0x28
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_COMPILED_METHOD_UNLOAD				0x29
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_DYNAMIC_CODE_GENERATED				0x2A
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_DATA_DUMP_REQUEST					0x2B
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_INIT 0x16
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_DEATH 0x17
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_THREAD_START 0x18
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_THREAD_END 0x19
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_CLASS_FILE_LOAD_HOOK 0x1A
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_CLASS_LOAD 0x1B
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_CLASS_PREPARE 0x1C
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_START 0x1D
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_EXCEPTION 0x1E
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_EXCEPTION_CATCH 0x1F
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_SINGLE_STEP 0x20
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_FRAME_POP 0x21
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_BREAKPOINT 0x22
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_FIELD_ACCESS 0x23
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_FIELD_MODIFICATION 0x24
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_METHOD_ENTRY 0x25
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_METHOD_EXIT 0x26
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_NATIVE_METHOD_BIND 0x27
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_COMPILED_METHOD_LOAD 0x28
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_COMPILED_METHOD_UNLOAD 0x29
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_DYNAMIC_CODE_GENERATED 0x2A
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_DATA_DUMP_REQUEST 0x2B
 /* 0x2C Reserved for JVMTI event */
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_WAIT						0x2D
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_WAITED						0x2E
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_CONTENDED_ENTER				0x2F
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_CONTENDED_ENTERED			0x30
-/* 0x31 Reserved for JVMTI event */
-/* 0x32 Reserved for JVMTI event */
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_WAIT 0x2D
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_WAITED 0x2E
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_CONTENDED_ENTER 0x2F
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_MONITOR_CONTENDED_ENTERED 0x30
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VIRTUAL_THREAD_MOUNT 0x31
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VIRTUAL_THREAD_UNMOUNT 0x32
 /* 0x33 Reserved for JVMTI event */
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_RESOURCE_EXHAUSTED					0x34
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_GC_START							0x35
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_GC_FINISH							0x36
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_OBJECT_FREE							0x37
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_OBJECT_ALLOC						0x38
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_RESOURCE_EXHAUSTED 0x34
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_GC_START 0x35
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_GC_FINISH 0x36
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_OBJECT_FREE 0x37
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_VM_OBJECT_ALLOC 0x38
 /* 0x39 Reserved for JVMTI event */
-#define J9_JNI_OFFLOAD_SWITCH_JVMTI_SAMPLED_OBJECT_ALLOC				0x3A
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_COMPILING_START					0x3B
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_COMPILING_END						0x3C
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_INSTRUMENTABLE_OBJECT_ALLOC		0x3D
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VM_DUMP_START						0x3E
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VM_DUMP_END						0x3F
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_GC_CYCLE_START					0x40
-#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_GC_CYCLE_FINISH					0x41
-#define J9_JNI_OFFLOAD_SWITCH_TRACE_SUBSCRIBER_THREAD					0x42
+#define J9_JNI_OFFLOAD_SWITCH_JVMTI_SAMPLED_OBJECT_ALLOC 0x3A
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_COMPILING_START 0x3B
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_COMPILING_END 0x3C
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_INSTRUMENTABLE_OBJECT_ALLOC 0x3D
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VM_DUMP_START 0x3E
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_VM_DUMP_END 0x3F
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_GC_CYCLE_START 0x40
+#define J9_JNI_OFFLOAD_SWITCH_J9JVMTI_GC_CYCLE_FINISH 0x41
+#define J9_JNI_OFFLOAD_SWITCH_TRACE_SUBSCRIBER_THREAD 0x42
 
 #define J9_JNI_OFFLOAD_SWITCH_THRESHOLD 0x4000
 #define J9_JNI_OFFLOAD_WITH_SUBTASKS_FLAG 0x40000000

runtime/oti/j9vm.hdf

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!--
-Copyright (c) 2006, 2022 IBM Corp. and others
+Copyright (c) 2006, 2023 IBM Corp. and others
 
 This program and the accompanying materials are made available under
 the terms of the Eclipse Public License 2.0 which accompanies this
@@ -1351,4 +1351,24 @@ typedef UDATA (* lookupNativeAddressCallback)(struct J9VMThread *currentThread,
 		<struct>J9VirtualThreadEndEvent</struct>
 		<data type="struct J9VMThread*" name="currentThread" description="current thread" />
 	</event>
+
+	<event>
+		<name>J9HOOK_VM_VIRTUAL_THREAD_MOUNT</name>
+		<description>
+			Triggered whenever a virtual thread mounts.
+			currentThread->threadObject is the virtual thread at the point of trigger.
+		</description>
+		<struct>J9VMVirtualThreadMountEvent</struct>
+		<data type="struct J9VMThread*" name="currentThread" description="current thread" />
+	</event>
+
+	<event>
+		<name>J9HOOK_VM_VIRTUAL_THREAD_UNMOUNT</name>
+		<description>
+			Triggered whenever a virtual thread unmounts.
+			currentThread->threadObject is the virtual thread at the point of trigger.
+		</description>
+		<struct>J9VMVirtualThreadUnmountEvent</struct>
+		<data type="struct J9VMThread*" name="currentThread" description="current thread" />
+	</event>
 </interface>