Merge pull request #19230 from babsingh/0.44_backports

Fix virtual thread interrupts
eclipse-openj9 · Mar 26, 2024 · 2e56066 · 2e56066
2 parents afb3132 + 41fb9ef
commit 2e56066
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Showing 2 changed files with 70 additions and 7 deletions.
diff --git a/runtime/jvmti/jvmtiHelpers.cpp b/runtime/jvmti/jvmtiHelpers.cpp
@@ -747,19 +747,35 @@ getThreadStateHelper(J9VMThread *currentThread, j9object_t threadObject, J9VMThr
 		if (vmstate & J9VMTHREAD_STATE_SUSPENDED) {
 			state |= JVMTI_THREAD_STATE_SUSPENDED;
 		}
+
+		if (vmstate & J9VMTHREAD_STATE_INTERRUPTED) {
+			state |= JVMTI_THREAD_STATE_INTERRUPTED;
+		}
+
 #if JAVA_SPEC_VERSION >= 19
-		/* Based on the internalSuspendState field, set the JVMTI
-		 * thread state to suspended for the corresponding thread.
+		/* Based on the isSuspendedInternal field, set the JVMTI thread state to suspended for
+		 * the corresponding thread.
 		 */
 		if (VM_VMHelpers::isThreadSuspended(currentThread, threadObject)) {
 			state |= JVMTI_THREAD_STATE_SUSPENDED;
 		} else {
 			state &= ~JVMTI_THREAD_STATE_SUSPENDED;
 		}
-#endif /* JAVA_SPEC_VERSION >= 19 */
-		if (vmstate & J9VMTHREAD_STATE_INTERRUPTED) {
+
+		/* Thread.deadInterrupt is Thread.interrupted in OJDK's Thread implementation. In JDK19+,
+		 * OJDK's Thread implementation is used, and multiple thread objects can be associated to
+		 * a J9VMThread: a virtual thread and its carrier thread. If a virtual thread is mounted,
+		 * then the carrier thread is unmounted and vice-versa. In such cases, J9VMThread's state
+		 * should not be used to determine if a thread object is interrupted. Instead,
+		 * Thread.interrupted is used to determine if a thread object is interrupted.
+		 */
+		if (J9VMJAVALANGTHREAD_DEADINTERRUPT(currentThread, threadObject)) {
 			state |= JVMTI_THREAD_STATE_INTERRUPTED;
+		} else {
+			state &= ~JVMTI_THREAD_STATE_INTERRUPTED;
 		}
+#endif /* JAVA_SPEC_VERSION >= 19 */
+
 #if defined(J9VM_INTERP_ATOMIC_FREE_JNI)
 		if (vmThread->inNative) {
 			state |= JVMTI_THREAD_STATE_IN_NATIVE;
@@ -899,6 +915,19 @@ getVirtualThreadState(J9VMThread *currentThread, jthread thread)
 		} else {
 			rc &= ~JVMTI_THREAD_STATE_SUSPENDED;
 		}
+
+		/* Thread.deadInterrupt is Thread.interrupted in OJDK's Thread implementation. In JDK19+,
+		 * OJDK's Thread implementation is used, and multiple thread objects can be associated to
+		 * a J9VMThread: a virtual thread and its carrier thread. If a virtual thread is mounted,
+		 * then the carrier thread is unmounted and vice-versa. In such cases, J9VMThread's state
+		 * should not be used to determine if a thread object is interrupted. Instead,
+		 * Thread.interrupted is used to determine if a thread object is interrupted.
+		 */
+		if (J9VMJAVALANGTHREAD_DEADINTERRUPT(currentThread, vThreadObject)) {
+			rc |= JVMTI_THREAD_STATE_INTERRUPTED;
+		} else {
+			rc &= ~JVMTI_THREAD_STATE_INTERRUPTED;
+		}
 		releaseVMThread(currentThread, targetThread, thread);
 	} else {
 		/* This is unreachable. */

diff --git a/runtime/oti/VMHelpers.hpp b/runtime/oti/VMHelpers.hpp
@@ -1410,8 +1410,24 @@ class VM_VMHelpers
 	{
 		J9VMThread *targetThread = J9VMJAVALANGTHREAD_THREADREF(currentThread, threadObject);
 		bool result = false;
+#if JAVA_SPEC_VERSION >= 19
+		/* Check if the mounted thread is suspended. */
+		bool isSuspended = false;
+		if (NULL != targetThread) {
+			isSuspended = isThreadSuspended(currentThread, targetThread->threadObject);
+		}
+#endif /* JAVA_SPEC_VERSION >= 19 */
 		/* If the thread is alive, ask the OS thread.  Otherwise, answer false. */
-		if (J9VMJAVALANGTHREAD_STARTED(currentThread, threadObject) && (NULL != targetThread)) {
+		if ((NULL != targetThread)
+		&& J9VMJAVALANGTHREAD_STARTED(currentThread, threadObject)
+#if JAVA_SPEC_VERSION >= 19
+		/* Thread.deadInterrupt is Thread.interrupted in OJDK's Thread implementation.
+		 * In JDK19+, OJDK's Thread implementation is used. If the mounted thread is
+		 * suspended, use Thread.interrupted to derive if the thread is interrupted.
+		 */
+		&& (!isSuspended)
+#endif /* JAVA_SPEC_VERSION >= 19 */
+		) {
 			if (omrthread_interrupted(targetThread->osThread)) {
 				result = true;
 			}
@@ -2043,8 +2059,26 @@ class VM_VMHelpers
 	threadInterruptImpl(J9VMThread *currentThread, j9object_t targetObject)
 	{
 		J9VMThread *targetThread = J9VMJAVALANGTHREAD_THREADREF(currentThread, targetObject);
-		if (J9VMJAVALANGTHREAD_STARTED(currentThread, targetObject) && (NULL != targetThread)) {
-			void (*sidecarInterruptFunction)(J9VMThread*) = currentThread->javaVM->sidecarInterruptFunction;
+		J9JavaVM *vm = currentThread->javaVM;
+#if JAVA_SPEC_VERSION >= 19
+		/* Check if the mounted thread is suspended. */
+		bool isSuspended = false;
+		if (NULL != targetThread) {
+			isSuspended = isThreadSuspended(currentThread, targetThread->threadObject);
+		}
+#endif /* JAVA_SPEC_VERSION >= 19 */
+		if ((NULL != targetThread)
+		&& J9VMJAVALANGTHREAD_STARTED(currentThread, targetObject)
+#if JAVA_SPEC_VERSION >= 19
+		/* Thread.deadInterrupt is Thread.interrupted in OJDK's Thread implementation.
+		 * In JDK19+, OJDK's Thread implementation is used. If the mounted thread is
+		 * suspended, only set Thread.interrupted to TRUE and do not wake/interrupt
+		 * the thread.
+		 */
+		&& (!isSuspended)
+#endif /* JAVA_SPEC_VERSION >= 19 */
+		) {
+			void (*sidecarInterruptFunction)(J9VMThread*) = vm->sidecarInterruptFunction;
 			if (NULL != sidecarInterruptFunction) {
 				sidecarInterruptFunction(targetThread);
 			}