(0.43) Virtual Thread Support

test/hotspot/jtreg/serviceability/jvmti/vthread/GetThreadState/libGetThreadStateTest.c

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "jni.h"
+#include "jvmti.h"
+
+static jvmtiEnv *jvmti;
+
+JNIEXPORT void JNICALL Java_GetThreadStateTest_init(JNIEnv *env, jclass clazz) {
+    JavaVM* vm;
+    jint res;
+    res = (*env)->GetJavaVM(env, &vm);
+    if (res != 0) {
+        (*env)->FatalError(env, "GetJavaVM failed");
+    } else {
+        res = (*vm)->GetEnv(vm, (void**)&jvmti, JVMTI_VERSION);
+        if (res != JNI_OK) {
+            (*env)->FatalError(env, "GetEnv failed");
+        }
+    }
+}
+
+JNIEXPORT jint JNICALL Java_GetThreadStateTest_jvmtiState(JNIEnv *env, jclass clazz, jobject thread) {
+    jvmtiError err;
+    jint state = 0;
+    err = (*jvmti)->GetThreadState(jvmti, thread, &state);
+    if (err != JVMTI_ERROR_NONE) {
+        (*env)->FatalError(env, "GetThreadState failed");
+    }
+    return state;
+}

test/hotspot/jtreg/serviceability/jvmti/vthread/VThreadEventTest/VThreadEventTest.java

@@ -0,0 +1,210 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8312174
+ * @summary missing JVMTI events from vthreads parked during JVMTI attach
+ * @requires vm.continuations
+ * @requires vm.jvmti
+ * @requires vm.compMode != "Xcomp"
+ * @run main/othervm/native
+ *     -Djdk.virtualThreadScheduler.parallelism=9
+ *     -Djdk.attach.allowAttachSelf=true -XX:+EnableDynamicAgentLoading VThreadEventTest attach
+ */
+
+import com.sun.tools.attach.VirtualMachine;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import java.util.concurrent.locks.LockSupport;
+import java.util.List;
+import java.util.ArrayList;
+
+/*
+ * The test uses custom implementation of the CountDownLatch class.
+ * The reason is we want the state of tested thread to be predictable.
+ * With java.util.concurrent.CountDownLatch it is not clear what thread state is expected.
+ */
+class CountDownLatch {
+    private int count = 0;
+
+    CountDownLatch(int count) {
+        this.count = count;
+    }
+
+    public synchronized void countDown() {
+        count--;
+        notify();
+    }
+
+    public synchronized void await() throws InterruptedException {
+        while (count > 0) {
+            wait(1);
+        }
+    }
+}
+
+public class VThreadEventTest {
+    static final int TCNT1 = 10;
+    static final int TCNT2 = 4;
+    static final int TCNT3 = 4;
+    static final int THREAD_CNT = TCNT1 + TCNT2 + TCNT3;
+
+    private static void log(String msg) { System.out.println(msg); }
+
+    private static native int threadEndCount();
+    private static native int threadMountCount();
+    private static native int threadUnmountCount();
+
+    private static volatile boolean attached;
+    private static boolean failed;
+    private static List<Thread> test1Threads = new ArrayList(TCNT1);
+
+    private static CountDownLatch ready0 = new CountDownLatch(THREAD_CNT);
+    private static CountDownLatch ready1 = new CountDownLatch(TCNT1);
+    private static CountDownLatch ready2 = new CountDownLatch(THREAD_CNT);
+    private static CountDownLatch mready = new CountDownLatch(1);
+
+    private static void await(CountDownLatch dumpedLatch) {
+        try {
+            dumpedLatch.await();
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    // The test1 vthreads are kept unmounted until interrupted after agent attach.
+    static final Runnable test1 = () -> {
+        synchronized (test1Threads) {
+            test1Threads.add(Thread.currentThread());
+        }
+        log("test1 vthread started");
+        ready0.countDown();
+        await(mready);
+        ready1.countDown(); // to guaranty state is not State.WAITING after await(mready)
+        try {
+            Thread.sleep(20000); // big timeout to keep unmounted until interrupted
+        } catch (InterruptedException ex) {
+            // it is expected, ignore
+        }
+        ready2.countDown();
+    };
+
+    // The test2 vthreads are kept mounted until agent attach.
+    static final Runnable test2 = () -> {
+        log("test2 vthread started");
+        ready0.countDown();
+        await(mready);
+        while (!attached) {
+            // keep mounted
+        }
+        ready2.countDown();
+    };
+
+    // The test3 vthreads are kept mounted until agent attach.
+    static final Runnable test3 = () -> {
+        log("test3 vthread started");
+        ready0.countDown();
+        await(mready);
+        while (!attached) {
+            // keep mounted
+        }
+        LockSupport.parkNanos(10_000_000L); // will cause extra mount and unmount
+        ready2.countDown();
+    };
+
+    public static void main(String[] args) throws Exception {
+        if (Runtime.getRuntime().availableProcessors() < 8) {
+            log("WARNING: test expects at least 8 processors.");
+        }
+        try (ExecutorService executorService = Executors.newVirtualThreadPerTaskExecutor()) {
+            for (int i = 0; i < TCNT1; i++) {
+                executorService.execute(test1);
+            }
+            for (int i = 0; i < TCNT2; i++) {
+                executorService.execute(test2);
+            }
+            for (int i = 0; i < TCNT3; i++) {
+                executorService.execute(test3);
+            }
+            await(ready0);
+            mready.countDown();
+            await(ready1); // to guarantee state is not State.TIMED_WAITING after await(mready) in test1()
+            // wait for test1 threads to reach TIMED_WAITING state in sleep()
+            for (Thread t : test1Threads) {
+                Thread.State state = t.getState();
+                log("DBG: state: " + state);
+                while (state != Thread.State.TIMED_WAITING) {
+                    Thread.sleep(10);
+                    state = t.getState();
+                    log("DBG: state: " + state);
+                }
+            }
+
+            VirtualMachine vm = VirtualMachine.attach(String.valueOf(ProcessHandle.current().pid()));
+            vm.loadAgentLibrary("VThreadEventTest");
+            Thread.sleep(200); // to allow the agent to get ready
+
+            attached = true;
+            for (Thread t : test1Threads) {
+                 t.interrupt();
+            }
+            ready2.await();
+        }
+        // wait until all VirtualThreadEnd events have been sent
+        for (int sleepNo = 1; threadEndCount() < THREAD_CNT; sleepNo++) {
+            Thread.sleep(100);
+            if (sleepNo % 100 == 0) { // 10 sec period of waiting
+                log("main: waited seconds: " + sleepNo/10);
+            }
+        }
+        int threadEndCnt = threadEndCount();
+        int threadMountCnt = threadMountCount();
+        int threadUnmountCnt = threadUnmountCount();
+        int threadEndExp = THREAD_CNT;
+        int threadMountExp = THREAD_CNT - TCNT2;
+        int threadUnmountExp = THREAD_CNT + TCNT3;
+
+        log("ThreadEnd cnt: "     + threadEndCnt     + " (expected: " + threadEndExp + ")");
+        log("ThreadMount cnt: "   + threadMountCnt   + " (expected: " + threadMountExp + ")");
+        log("ThreadUnmount cnt: " + threadUnmountCnt + " (expected: " + threadUnmountExp + ")");
+
+        if (threadEndCnt != threadEndExp) {
+            log("FAILED: unexpected count of ThreadEnd events");
+            failed = true;
+        }
+        if (threadMountCnt != threadMountExp) {
+            log("FAILED: unexpected count of ThreadMount events");
+            failed = true;
+        }
+        if (threadUnmountCnt != threadUnmountExp) {
+            log("FAILED: unexpected count of ThreadUnmount events");
+            failed = true;
+        }
+        if (failed) {
+            throw new RuntimeException("FAILED: event count is wrong");
+        }
+    }
+
+}
+

test/hotspot/jtreg/serviceability/jvmti/vthread/VThreadEventTest/libVThreadEventTest.cpp

@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+/*
+ * ===========================================================================
+ * (c) Copyright IBM Corp. 2023, 2023 All Rights Reserved
+ * ===========================================================================
+ */
+
+#include <cstring>
+#include <jvmti.h>
+#include <atomic>
+#include "jvmti_common.h"
+
+extern "C" {
+
+static jvmtiEnv *jvmti = nullptr;
+static std::atomic<int> thread_end_cnt(0);
+static std::atomic<int> thread_unmount_cnt(0);
+static std::atomic<int> thread_mount_cnt(0);
+
+void JNICALL VirtualThreadEnd(jvmtiEnv *jvmti, JNIEnv* jni, jthread vthread) {
+  thread_end_cnt++;
+}
+
+void JNICALL VirtualThreadMount(jvmtiEnv* jvmti, ...) {
+  thread_mount_cnt++;
+}
+
+void JNICALL VirtualThreadUnmount(jvmtiEnv* jvmti, ...) {
+  thread_unmount_cnt++;
+}
+
+JNIEXPORT jint JNICALL
+Java_VThreadEventTest_threadEndCount(JNIEnv* jni, jclass clazz) {
+  return thread_end_cnt;
+}
+
+JNIEXPORT jint JNICALL
+Java_VThreadEventTest_threadMountCount(JNIEnv* jni, jclass clazz) {
+  return thread_mount_cnt;
+}
+
+JNIEXPORT jint JNICALL
+Java_VThreadEventTest_threadUnmountCount(JNIEnv* jni, jclass clazz) {
+  return thread_unmount_cnt;
+}
+
+JNIEXPORT jint JNICALL
+Agent_OnAttach(JavaVM *vm, char *options, void *reserved) {
+  jvmtiEventCallbacks callbacks;
+  jvmtiCapabilities caps;
+  jvmtiError err;
+
+  LOG("Agent_OnAttach started\n");
+  if (vm->GetEnv(reinterpret_cast<void **>(&jvmti), JVMTI_VERSION) != JNI_OK || !jvmti) {
+    LOG("Could not initialize JVMTI env\n");
+    return JNI_ERR;
+  }
+  memset(&caps, 0, sizeof(caps));
+  caps.can_support_virtual_threads = 1;
+  check_jvmti_error(jvmti->AddCapabilities(&caps), "AddCapabilities");
+
+  memset(&callbacks, 0, sizeof(callbacks));
+  callbacks.VirtualThreadEnd = &VirtualThreadEnd;
+
+  err = jvmti->SetEventCallbacks(&callbacks, (jint)sizeof(callbacks));
+  check_jvmti_error(err, "SetEventCallbacks");
+
+  err = set_ext_event_callback(jvmti, "VirtualThreadMount", VirtualThreadMount);
+  check_jvmti_error(err, "SetExtEventCallback for VirtualThreadMount");
+
+  err = set_ext_event_callback(jvmti, "VirtualThreadUnmount", VirtualThreadUnmount);
+  check_jvmti_error(err, "SetExtEventCallback for VirtualThreadUnmount");
+
+  err = jvmti->SetEventNotificationMode(JVMTI_ENABLE, JVMTI_EVENT_VIRTUAL_THREAD_END, nullptr);
+  check_jvmti_error(err, "SetEventNotificationMode for VirtualThreadEnd");
+
+  err = set_ext_event_notification_mode(jvmti, JVMTI_ENABLE, "VirtualThreadMount", NULL);
+  check_jvmti_error(err, "SetEventNotificationMode for VirtualThreadMount");
+
+  err = set_ext_event_notification_mode(jvmti, JVMTI_ENABLE, "VirtualThreadUnmount", NULL);
+  check_jvmti_error(err, "SetEventNotificationMode for VirtualThreadUnmount");
+
+  LOG("vthread events enabled\n");
+  return JVMTI_ERROR_NONE;
+}
+
+} // extern "C"
+