eclipse-openj9 · babsingh · Dec 18, 2024 · Dec 18, 2024
diff --git a/jcl/src/java.base/share/classes/com/ibm/oti/vm/VM.java b/jcl/src/java.base/share/classes/com/ibm/oti/vm/VM.java
@@ -639,6 +639,9 @@ public static Properties internalGetProperties() {
 }
 
 /*[IF JFR_SUPPORT]*/
+
+public static native boolean isJFREnabled();
+
 /**
  * Check if a JFR recording has been started.
  *

diff --git a/jcl/src/java.base/share/classes/openj9/internal/tools/attach/target/DiagnosticUtils.java b/jcl/src/java.base/share/classes/openj9/internal/tools/attach/target/DiagnosticUtils.java
@@ -700,14 +700,17 @@ private static DiagnosticProperties doCheckpointJVM(String diagnosticCommand) {
 /*[ENDIF] CRAC_SUPPORT */
 
 /*[IF JFR_SUPPORT]*/
-		commandTable.put(DIAGNOSTICS_JFR_START, DiagnosticUtils::doJFR);
-		helpTable.put(DIAGNOSTICS_JFR_START, DIAGNOSTICS_JFR_START_HELP);
+		if (VM.isJFREnabled()) {
+			commandTable.put(DIAGNOSTICS_JFR_START, DiagnosticUtils::doJFR);
+			helpTable.put(DIAGNOSTICS_JFR_START, DIAGNOSTICS_JFR_START_HELP);
 
-		commandTable.put(DIAGNOSTICS_JFR_DUMP, DiagnosticUtils::doJFR);
-		helpTable.put(DIAGNOSTICS_JFR_DUMP, DIAGNOSTICS_JFR_DUMP_HELP);
+			commandTable.put(DIAGNOSTICS_JFR_DUMP, DiagnosticUtils::doJFR);
+			helpTable.put(DIAGNOSTICS_JFR_DUMP, DIAGNOSTICS_JFR_DUMP_HELP);
+
+			commandTable.put(DIAGNOSTICS_JFR_STOP, DiagnosticUtils::doJFR);
+			helpTable.put(DIAGNOSTICS_JFR_STOP, DIAGNOSTICS_JFR_STOP_HELP);
+		}
 
-		commandTable.put(DIAGNOSTICS_JFR_STOP, DiagnosticUtils::doJFR);
-		helpTable.put(DIAGNOSTICS_JFR_STOP, DIAGNOSTICS_JFR_STOP_HELP);
 /*[ENDIF] JFR_SUPPORT */
 	}
 }
diff --git a/runtime/jcl/common/com_ibm_oti_vm_VM.cpp b/runtime/jcl/common/com_ibm_oti_vm_VM.cpp
@@ -194,6 +194,14 @@ Java_com_ibm_oti_vm_VM_isJVMInSingleThreadedMode(JNIEnv *env, jclass unused)
 }
 
 #if defined(J9VM_OPT_JFR)
+jboolean JNICALL
+Java_com_ibm_oti_vm_VM_isJFREnabled(JNIEnv *env, jclass unused)
+{
+	J9JavaVM *vm = ((J9VMThread *)env)->javaVM;
+
+	return vm->internalVMFunctions->isJFREnabled(vm) ? JNI_TRUE : JNI_FALSE;
+}
+
 jboolean JNICALL
 Java_com_ibm_oti_vm_VM_isJFRRecordingStarted(JNIEnv *env, jclass unused)
 {

diff --git a/runtime/jcl/exports.cmake b/runtime/jcl/exports.cmake
@@ -694,6 +694,7 @@ endif()
 
 if(J9VM_OPT_JFR)
 	omr_add_exports(jclse
+		Java_com_ibm_oti_vm_VM_isJFREnabled
 		Java_com_ibm_oti_vm_VM_isJFRRecordingStarted
 		Java_com_ibm_oti_vm_VM_jfrDump
 		Java_com_ibm_oti_vm_VM_setJFRRecordingFileName

diff --git a/runtime/jcl/uma/jfr_jdk11_exports.xml b/runtime/jcl/uma/jfr_jdk11_exports.xml
@@ -20,6 +20,12 @@ OpenJDK Assembly Exception [2].
 SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
 -->
 <exports group="jfr_jdk11">
+	<export name="Java_com_ibm_oti_vm_VM_isJFRRecordingStarted" />
+	<export name="Java_com_ibm_oti_vm_VM_jfrDump" />
+	<export name="Java_com_ibm_oti_vm_VM_setJFRRecordingFileName" />
+	<export name="Java_com_ibm_oti_vm_VM_startJFR" />
+	<export name="Java_com_ibm_oti_vm_VM_stopJFR" />
+	<export name="Java_com_ibm_oti_vm_VM_triggerExecutionSample" />
 	<export name="Java_jdk_jfr_internal_JVM_abort" />
 	<export name="Java_jdk_jfr_internal_JVM_addStringConstant" />
 	<export name="Java_jdk_jfr_internal_JVM_beginRecording" />

diff --git a/runtime/jcl/uma/jfr_jdk21_exports.xml b/runtime/jcl/uma/jfr_jdk21_exports.xml
@@ -20,12 +20,6 @@ OpenJDK Assembly Exception [2].
 SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
 -->
 <exports group="jfr_jdk21">
-	<export name="Java_com_ibm_oti_vm_VM_isJFRRecordingStarted" />
-	<export name="Java_com_ibm_oti_vm_VM_jfrDump" />
-	<export name="Java_com_ibm_oti_vm_VM_setJFRRecordingFileName" />
-	<export name="Java_com_ibm_oti_vm_VM_startJFR" />
-	<export name="Java_com_ibm_oti_vm_VM_stopJFR" />
-	<export name="Java_com_ibm_oti_vm_VM_triggerExecutionSample" />
 	<export name="Java_jdk_jfr_internal_JVM_abort" />
 	<export name="Java_jdk_jfr_internal_JVM_addStringConstant" />
 	<export name="Java_jdk_jfr_internal_JVM_beginRecording" />

diff --git a/runtime/oti/j9consts.h b/runtime/oti/j9consts.h
@@ -369,6 +369,9 @@ extern "C" {
 #define J9_EXTENDED_RUNTIME2_RAMSTATE_SNAPSHOT_RUN 0x40000000
 #define J9_EXTENDED_RUNTIME2_RAMSTATE_RESTORE_RUN 0x80000000
 
+/* constants for J9JavaVM.extendedRuntimeFlags3 */
+#define J9_EXTENDED_RUNTIME3_START_FLIGHT_RECORDING 0x1
+
 #define J9_OBJECT_HEADER_AGE_DEFAULT 0xA /* OBJECT_HEADER_AGE_DEFAULT */
 #define J9_OBJECT_HEADER_SHAPE_MASK 0xE /* OBJECT_HEADER_SHAPE_MASK */
 #define J9_OBJECT_HEADER_REMEMBERED_BITS_TO_SET 0x10 /* OBJECT_HEADER_LOWEST_REMEMBERED */

diff --git a/runtime/oti/j9nonbuilder.h b/runtime/oti/j9nonbuilder.h
@@ -5263,6 +5263,7 @@ typedef struct J9InternalVMFunctions {
 #endif /* defined(J9VM_ZOS_3164_INTEROPERABILITY) && (JAVA_SPEC_VERSION >= 17) */
 #if defined(J9VM_OPT_JFR)
 	jint (*initializeJFR)(struct J9JavaVM *vm, BOOLEAN lateInit);
+	jboolean (*isJFREnabled)(struct J9JavaVM *vm);
 	jboolean (*isJFRRecordingStarted)(struct J9JavaVM *vm);
 	void (*jfrDump)(struct J9VMThread *currentThread, BOOLEAN finalWrite);
 	void (*jfrExecutionSample)(struct J9VMThread *currentThread, struct J9VMThread *sampleThread);
@@ -5796,6 +5797,7 @@ typedef struct J9JavaVM {
 	U_32 runtimeFlags;
 	U_32 extendedRuntimeFlags;
 	U_32 extendedRuntimeFlags2;
+	U_32 extendedRuntimeFlags3;
 	UDATA zeroOptions;
 	struct J9Pool* hotFieldClassInfoPool;
 	omrthread_monitor_t hotFieldClassInfoPoolMutex;

diff --git a/runtime/oti/jclprots.h b/runtime/oti/jclprots.h
@@ -1275,6 +1275,8 @@ Java_com_ibm_oti_vm_VM_isJVMInSingleThreadedMode(JNIEnv *env, jclass unused);
 
 #if defined(J9VM_OPT_JFR)
 jboolean JNICALL
+Java_com_ibm_oti_vm_VM_isJFREnabled(JNIEnv *env, jclass unused);
+jboolean JNICALL
 Java_com_ibm_oti_vm_VM_isJFRRecordingStarted(JNIEnv *env, jclass unused);
 void JNICALL
 Java_com_ibm_oti_vm_VM_jfrDump(JNIEnv *env, jclass unused);

diff --git a/runtime/oti/jvminit.h b/runtime/oti/jvminit.h
@@ -587,6 +587,8 @@ enum INIT_STAGE {
 #define VMOPT_XXFLIGHTRECORDER "-XX:+FlightRecorder"
 #define VMOPT_XXNOFLIGHTRECORDER "-XX:-FlightRecorder"
 
+#define VMOPT_XXSTARTFLIGHTRECORDING "-XX:StartFlightRecording"
+
 #define VMOPT_XXCONTINUATIONCACHE "-XX:ContinuationCache:"
 
 #if JAVA_SPEC_VERSION >= 22

diff --git a/runtime/oti/vm_api.h b/runtime/oti/vm_api.h
@@ -5418,6 +5418,16 @@ hasMemoryScope(J9VMThread *walkThread, j9object_t scope);
 jint
 initializeJFR(J9JavaVM *vm, BOOLEAN lateInit);
 
+/**
+ * Check if a JFR is enabled on the JVM.
+ *
+ * @param vm[in] the J9JavaVM
+ *
+ * @returns JNI_TRUE if a JFR enabled, JNI_FALSE otherwise
+ */
+jboolean
+isJFREnabled(J9JavaVM *vm);
+
 /**
  * Check if a JFR recording has been started.
  *

diff --git a/runtime/vm/intfunc.c b/runtime/vm/intfunc.c
@@ -463,6 +463,7 @@ J9InternalVMFunctions J9InternalFunctions = {
 #endif /* defined(J9VM_ZOS_3164_INTEROPERABILITY) && (JAVA_SPEC_VERSION >= 17) */
 #if defined(J9VM_OPT_JFR)
 	initializeJFR,
+	isJFREnabled,
 	isJFRRecordingStarted,
 	jfrDump,
 	jfrExecutionSample,

diff --git a/runtime/vm/jfr.cpp b/runtime/vm/jfr.cpp
@@ -852,6 +852,12 @@ initializeEventFields(J9VMThread *currentThread, J9JFREvent *event, UDATA eventT
 	event->vmThread = currentThread;
 }
 
+jboolean
+isJFREnabled(J9JavaVM *vm)
+{
+	return J9_ARE_ANY_BITS_SET(vm->extendedRuntimeFlags2, J9_EXTENDED_RUNTIME2_JFR_ENABLED) ? JNI_TRUE : JNI_FALSE;
+}
+
 jboolean
 isJFRRecordingStarted(J9JavaVM *vm)
 {

diff --git a/runtime/vm/jvminit.c b/runtime/vm/jvminit.c
@@ -4321,12 +4321,19 @@ processVMArgsFromFirstToLast(J9JavaVM * vm)
 	{
 		IDATA flightRecorder = FIND_AND_CONSUME_VMARG(EXACT_MATCH, VMOPT_XXFLIGHTRECORDER, NULL);
 		IDATA noFlightRecorder = FIND_AND_CONSUME_VMARG(EXACT_MATCH, VMOPT_XXNOFLIGHTRECORDER, NULL);
-		if (flightRecorder > noFlightRecorder) {
-			vm->extendedRuntimeFlags2 |= J9_EXTENDED_RUNTIME2_JFR_ENABLED;
-		} else if (flightRecorder < noFlightRecorder) {
+
+		vm->extendedRuntimeFlags2 |= J9_EXTENDED_RUNTIME2_JFR_ENABLED;
+
+		if (flightRecorder < noFlightRecorder) {
 			vm->extendedRuntimeFlags2 &= ~(UDATA)J9_EXTENDED_RUNTIME2_JFR_ENABLED;
 		}
 	}
+	{
+		if (0 <= FIND_AND_CONSUME_VMARG(EXACT_MATCH, VMOPT_XXSTARTFLIGHTRECORDING, NULL)) {
+			vm->extendedRuntimeFlags3 |= J9_EXTENDED_RUNTIME3_START_FLIGHT_RECORDING;
+		}
+	}
+
 #endif /* defined(J9VM_OPT_JFR) */
 
 	if (FIND_AND_CONSUME_VMARG(EXACT_MATCH, VMOPT_XXKEEPJNIIDS, NULL) != -1) {
@@ -7585,8 +7592,10 @@ protectedInitializeJavaVM(J9PortLibrary* portLibrary, void * userData)
 
 #if defined(J9VM_OPT_JFR)
 	if (J9_ARE_ANY_BITS_SET(vm->extendedRuntimeFlags2, J9_EXTENDED_RUNTIME2_JFR_ENABLED)) {
-		if (JNI_OK != initializeJFR(vm, FALSE)) {
-			goto error;
+		if (J9_ARE_ANY_BITS_SET(vm->extendedRuntimeFlags3, J9_EXTENDED_RUNTIME3_START_FLIGHT_RECORDING)) {
+			if (JNI_OK != initializeJFR(vm, FALSE)) {
+				goto error;
+			}
 		}
 	}
 #endif /* defined(J9VM_OPT_JFR) */

diff --git a/test/functional/cmdLineTests/jfr/jfr.xml b/test/functional/cmdLineTests/jfr/jfr.xml
@@ -27,22 +27,56 @@ SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-ex
 <suite id="JFR Tests" timeout="300">
 	<envvar name="OPENJ9_METADATA_BLOB_FILE_PATH" value="$METADATA_BLOB_PATH$" />
 	<test id="triggerExecutionSample">
-		<command>$EXE$ -XX:+FlightRecorder --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.TriggerExecutionSample</command>
+		<command>$EXE$ -XX:StartFlightRecording --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.TriggerExecutionSample</command>
 		<return type="success" value="0" />
 	</test>
 	<test id="runWorkload - approx 30seconds">
-		<command>$EXE$ -XX:+FlightRecorder --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.WorkLoad</command>
+		<command>$EXE$ -XX:StartFlightRecording --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.WorkLoad</command>
 		<output type="success" caseSensitive="yes" regex="no">All runs complete.</output>
 		<output type="failure" caseSensitive="yes" regex="no">Exception</output>
 	</test>
 	<test id="runWorkload 2 - approx 2mins">
-		<command>$EXE$ -XX:+FlightRecorder --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.WorkLoad 200 20000 200</command>
+		<command>$EXE$ -XX:StartFlightRecording --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.WorkLoad 200 20000 200</command>
 		<output type="success" caseSensitive="yes" regex="no">All runs complete.</output>
 		<output type="failure" caseSensitive="yes" regex="no">Exception</output>
 	</test>
-	<test id="runWorkload 2 - approx 2mins">
+	<test id="VM API Test - approx 2mins">
 		<command>$EXE$ --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.VMAPITest</command>
 		<output type="success" caseSensitive="yes" regex="no">All runs complete.</output>
 		<output type="failure" caseSensitive="yes" regex="no">Failed</output>
 	</test>
+	<test id="Test JFR enablement 1">
+		<command>$EXE$ --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.JFRCMDLineTest</command>
+		<output type="required" caseSensitive="yes" regex="no">All runs complete</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR recording has started</output>
+		<output type="success" caseSensitive="yes" regex="no">JFR is enabled</output>
+	</test>
+	<test id="Test JFR enablement 2">
+		<command>$EXE$  -XX:+FlightRecorder --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.JFRCMDLineTest</command>
+		<output type="required" caseSensitive="yes" regex="no">All runs complete</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR recording has started</output>
+		<output type="success" caseSensitive="yes" regex="no">JFR is enabled</output>
+	</test>
+	<test id="Test JFR enablement 3">
+		<command>$EXE$  -XX:-FlightRecorder --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.JFRCMDLineTest</command>
+		<output type="required" caseSensitive="yes" regex="no">All runs complete</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR recording has started</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR is enabled</output>
+		<output type="success" caseSensitive="yes" regex="no">JFR is not enabled</output>
+	</test>
+	<test id="Test Start flight recording 1">
+		<command>$EXE$  -XX:-FlightRecorder -XX:StartFlightRecording --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.JFRCMDLineTest</command>
+		<output type="required" caseSensitive="yes" regex="no">All runs complete</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR recording has started</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR is enabled</output>
+		<output type="success" caseSensitive="yes" regex="no">JFR is not enabled</output>
+	</test>
+	<test id="Test Start flight recording 2">
+		<command>$EXE$ -XX:StartFlightRecording --add-exports java.base/com.ibm.oti.vm=ALL-UNNAMED -cp $RESJAR$ org.openj9.test.JFRCMDLineTest</command>
+		<output type="required" caseSensitive="yes" regex="no">All runs complete</output>
+		<output type="success" caseSensitive="yes" regex="no">JFR recording has started</output>
+		<output type="success" caseSensitive="yes" regex="no">JFR is enabled</output>
+		<output type="failure" caseSensitive="yes" regex="no">JFR is not enabled</output>
+	</test>
+
 </suite>
diff --git a/test/functional/cmdLineTests/jfr/src/org/openj9/test/JFRCMDLineTest.java b/test/functional/cmdLineTests/jfr/src/org/openj9/test/JFRCMDLineTest.java
@@ -0,0 +1,46 @@
+/*
+ * Copyright IBM Corp. and others 2024
+ *
+ * This program and the accompanying materials are made available under
+ * the terms of the Eclipse Public License 2.0 which accompanies this
+ * distribution and is available at https://www.eclipse.org/legal/epl-2.0/
+ * or the Apache License, Version 2.0 which accompanies this distribution and
+ * is available at https://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * This Source Code may also be made available under the following
+ * Secondary Licenses when the conditions for such availability set
+ * forth in the Eclipse Public License, v. 2.0 are satisfied: GNU
+ * General Public License, version 2 with the GNU Classpath
+ * Exception [1] and GNU General Public License, version 2 with the
+ * OpenJDK Assembly Exception [2].
+ *
+ * [1] https://www.gnu.org/software/classpath/license.html
+ * [2] https://openjdk.org/legal/assembly-exception.html
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR Apache-2.0 OR GPL-2.0-only WITH Classpath-exception-2.0 OR GPL-2.0-only WITH OpenJDK-assembly-exception-1.0
+ */
+package org.openj9.test;
+
+import com.ibm.oti.vm.VM;
+
+public class JFRCMDLineTest {
+
+	public static void main(String[] args) throws Throwable {
+
+		final WorkLoad workLoad = new WorkLoad(200, 20000, 200);
+
+		if (VM.isJFRRecordingStarted()) {
+			System.out.println("JFR recording has started");
+		} else {
+			System.out.println("JFR recording has not started");
+		}
+
+		if (VM.isJFREnabled()) {
+			System.out.println("JFR is enabled");
+		} else {
+			System.out.println("JFR is not enabled");
+		}
+
+		System.out.println("All runs complete");
+	}
+}
-Original file line number
+Diff line change
@@ Expand Up / @@ -639,6 +639,9 @@ public static Properties internalGetProperties() { @@
     }
     /*[IF JFR_SUPPORT]*/
+    public static native boolean isJFREnabled();
     /**
      * Check if a JFR recording has been started.
      *
@@ Expand Down @@