1 /*
  2  * Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  */
 23 
 24 /**
 25  * @test id=default
 26  * @summary Do not suspend virtual threads in a critical section.
 27  * @bug 8311218
 28  * @requires vm.continuations
 29  * @library /testlibrary
 30  * @run main/othervm SuspendWithInterruptLock
 31  */
 32 
 33 /**
 34  * @test id=xint
 35  * @summary Do not suspend virtual threads in a critical section.
 36  * @bug 8311218
 37  * @requires vm.continuations
 38  * @library /testlibrary
 39  * @run main/othervm -Xint SuspendWithInterruptLock
 40  */
 41 
 42 import jvmti.JVMTIUtils;
 43 
 44 public class SuspendWithInterruptLock {
 45     static volatile boolean done;
 46 
 47     public static void main(String[] args) throws Exception {
 48         Thread yielder = Thread.ofVirtual().name("yielder").start(() -> yielder());
 49         Thread stateReader = Thread.ofVirtual().name("stateReader").start(() -> stateReader(yielder));
 50         Thread suspender = new Thread(() -> suspender(stateReader));
 51         suspender.start();
 52 
 53         yielder.join();
 54         stateReader.join();
 55         suspender.join();
 56     }
 57 
 58     static private void yielder() {
 59         int iterations = 100_000;
 60         while (iterations-- > 0) {
 61             Thread.yield();
 62         }
 63         done = true;
 64     }
 65 
 66     static private void stateReader(Thread target) {
 67         while (!done) {
 68             target.getState();
 69         }
 70     }
 71 
 72     static private void suspender(Thread target) {
 73         while (!done) {
 74             suspendThread(target);
 75             sleep(1);
 76             resumeThread(target);
 77             // Allow progress
 78             sleep(5);
 79         }
 80     }
 81 
 82     static void suspendThread(Thread t) {
 83         try {
 84             JVMTIUtils.suspendThread(t);
 85         } catch (JVMTIUtils.JvmtiException e) {
 86             if (e.getCode() != JVMTIUtils.JVMTI_ERROR_THREAD_NOT_ALIVE) {
 87                 throw e;
 88             }
 89         }
 90     }
 91 
 92     static void resumeThread(Thread t) {
 93         try {
 94             JVMTIUtils.resumeThread(t);
 95         } catch (JVMTIUtils.JvmtiException e) {
 96             if (e.getCode() != JVMTIUtils.JVMTI_ERROR_THREAD_NOT_ALIVE) {
 97                 throw e;
 98             }
 99         }
100     }
101 
102     static private void sleep(long millis) {
103         try {
104             Thread.sleep(millis);
105         } catch (InterruptedException e) {}
106     }
107 }
108