--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/hotspot/jtreg/serviceability/jvmti/SuspendWithCurrentThread/libSuspendWithCurrentThread.cpp	Thu Oct 10 01:10:26 2019 +0000
@@ -0,0 +1,209 @@
+/*
+ * Copyright (c) 2019, 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 <string.h>
+#include "jvmti.h"
+
+extern "C" {
+
+static jvmtiEnv* jvmti = NULL;
+static jthread* threads = NULL;
+static jsize threads_count = 0;
+static jrawMonitorID agent_monitor = NULL;
+
+#define LOG(...) \
+  do { \
+    printf(__VA_ARGS__); \
+    printf("\n"); \
+    fflush(stdout); \
+  } while (0)
+
+static void
+check_jvmti_status(JNIEnv* jni, jvmtiError err, const char* msg) {
+  if (err != JVMTI_ERROR_NONE) {
+    LOG("check_jvmti_status: JVMTI function returned error: %d", err);
+    jni->FatalError(msg);
+  }
+}
+
+static void
+agent_lock(JNIEnv* jni) {
+  jvmtiError err = jvmti->RawMonitorEnter(agent_monitor);
+  check_jvmti_status(jni, err, "monitor_enter: error in JVMTI RawMonitorEnter");
+}
+
+static void
+agent_unlock(JNIEnv* jni) {
+  jvmtiError err = jvmti->RawMonitorExit(agent_monitor);
+  check_jvmti_status(jni, err, "monitor_exit: error in JVMTI RawMonitorExit");
+}
+
+JNIEXPORT void JNICALL
+Java_SuspendWithCurrentThread_registerTestedThreads(JNIEnv *jni, jclass cls, jobjectArray threadsArr) {
+  LOG("\nregisterTestedThreads: started");
+  threads_count = jni->GetArrayLength(threadsArr);
+
+  jvmtiError err = jvmti->Allocate((threads_count * sizeof(jthread)),
+                                   (unsigned char**)&threads);
+  check_jvmti_status(jni, err, "registerTestedThreads: error in JVMTI Allocate threads array");
+
+  for (int i = 0; i < threads_count; i++) {
+    jobject elem = jni->GetObjectArrayElement(threadsArr, i);
+    threads[i] = (jthread)jni->NewGlobalRef(elem);
+  }
+  LOG("registerTestedThreads: finished\n");
+}
+
+/* This function is executed on the suspender thread, not the Main thread */
+JNIEXPORT void JNICALL
+Java_ThreadToSuspend_init(JNIEnv *jni, jclass cls) {
+  jvmtiError err = jvmti->CreateRawMonitor("Agent monitor", &agent_monitor);
+  check_jvmti_status(jni, err, "Java_ThreadToSuspend_init: error in JVMTI CreateRawMonitor");
+
+  // Main thread has to wait for the suspender thread to complete tested threads suspension
+  agent_lock(jni);
+}
+
+/* This function is executed on the suspender thread which is not Main thread */
+JNIEXPORT void JNICALL
+Java_ThreadToSuspend_suspendTestedThreads(JNIEnv *jni, jclass cls) {
+  jvmtiError* results = NULL;
+  jvmtiError err;
+
+  LOG("\nsuspendTestedThreads: started");
+  err = jvmti->Allocate((threads_count * sizeof(jvmtiError)),
+                        (unsigned char**)&results);
+  check_jvmti_status(jni, err, "suspendTestedThreads: error in JVMTI Allocate results array");
+
+  LOG("suspendTestedThreads: before JVMTI SuspendThreadList");
+  err = jvmti->SuspendThreadList(threads_count, threads, results);
+  check_jvmti_status(jni, err, "suspendTestedThreads: error in JVMTI SuspendThreadList");
+
+  LOG("suspendTestedThreads: check and print SuspendThreadList results:");
+  for (int i = 0; i < threads_count; i++) {
+    LOG("  thread #%d: (%d)", i, (int)results[i]);
+    check_jvmti_status(jni, results[i], "suspendTestedThreads: error in SuspendThreadList results[i]");
+  }
+  LOG("suspendTestedThreads: finished\n");
+
+  // Allow the Main thread to inspect the result of tested threads suspension
+  agent_unlock(jni);
+
+  err = jvmti->Deallocate((unsigned char*)results);
+  check_jvmti_status(jni, err, "suspendTestedThreads: error in JVMTI Deallocate results");
+}
+
+JNIEXPORT jboolean JNICALL
+Java_SuspendWithCurrentThread_checkTestedThreadsSuspended(JNIEnv *jni, jclass cls) {
+  LOG("checkTestedThreadsSuspended: started");
+
+  // Block until the suspender thread competes the tested threads suspension
+  agent_lock(jni);
+  agent_unlock(jni);
+
+  for (int i = 0; i < threads_count; i++) {
+    jint state = 0;
+    jvmtiError err = jvmti->GetThreadState(threads[i], &state);
+    check_jvmti_status(jni, err, "checkTestedThreadsSuspended: error in GetThreadState");
+
+    if ((state & JVMTI_THREAD_STATE_SUSPENDED) == 0) {
+      LOG("thread #%d has not been suspended yet: "
+             "#   state: (%#x)", i, (int)state);
+      jni->FatalError("checkTestedThreadsSuspended: error: expected all tested threads suspended");
+    }
+  }
+  LOG("checkTestedThreadsSuspended: finished\n");
+  return JNI_TRUE;
+}
+
+JNIEXPORT void JNICALL
+Java_SuspendWithCurrentThread_resumeTestedThreads(JNIEnv *jni, jclass cls) {
+  jvmtiError* results = NULL;
+  jvmtiError err;
+
+  LOG("\nresumeTestedThreads: started");
+  err = jvmti->Allocate((threads_count * sizeof(jvmtiError)),
+                        (unsigned char**)&results);
+  check_jvmti_status(jni, err, "resumeTestedThreads: error in JVMTI Allocate results array");
+
+  LOG("resumeTestedThreads: before JVMTI ResumeThreadList");
+  err = jvmti->ResumeThreadList(threads_count, threads, results);
+  check_jvmti_status(jni, err, "resumeTestedThreads: error in ResumeThreadList");
+
+  LOG("resumeTestedThreads: check and print ResumeThreadList results:");
+  for (int i = 0; i < threads_count; i++) {
+    LOG("  thread #%d: (%d)", i, (int)results[i]);
+    check_jvmti_status(jni, results[i], "resumeTestedThreads: error in ResumeThreadList results[i]");
+  }
+
+  err = jvmti->Deallocate((unsigned char*)results);
+  check_jvmti_status(jni, err, "resumeTestedThreads: error in JVMTI Deallocate results");
+
+  LOG("resumeTestedThreads: finished\n");
+}
+
+JNIEXPORT void JNICALL
+Java_SuspendWithCurrentThread_releaseTestedThreadsInfo(JNIEnv *jni, jclass cls) {
+  jvmtiError err;
+
+  LOG("\nreleaseTestedThreadsInfo: started");
+  err = jvmti->DestroyRawMonitor(agent_monitor);
+  check_jvmti_status(jni, err, "releaseTestedThreadsInfo: error in JVMTI DestroyRawMonitor");
+
+  for (int i = 0; i < threads_count; i++) {
+    if (threads[i] != NULL) {
+      jni->DeleteGlobalRef(threads[i]);
+    }
+  }
+  err = jvmti->Deallocate((unsigned char*)threads);
+  check_jvmti_status(jni, err, "releaseTestedThreadsInfo: error in JVMTI Deallocate threads");
+
+  LOG("releaseTestedThreadsInfo: finished\n");
+}
+
+
+/** Agent library initialization. */
+
+JNIEXPORT jint JNICALL
+Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
+  LOG("\nAgent_OnLoad started");
+
+  // create JVMTI environment
+  if (jvm->GetEnv((void **) (&jvmti), JVMTI_VERSION) != JNI_OK) {
+    return JNI_ERR;
+  }
+
+  // add specific capabilities for suspending thread
+  jvmtiCapabilities suspendCaps;
+  memset(&suspendCaps, 0, sizeof(suspendCaps));
+  suspendCaps.can_suspend = 1;
+
+  jvmtiError err = jvmti->AddCapabilities(&suspendCaps);
+  if (err != JVMTI_ERROR_NONE) {
+    return JNI_ERR;
+  }
+  LOG("Agent_OnLoad finished\n");
+  return JNI_OK;
+}
+
+}