1 /* 2 * Copyright (c) 2004, 2018, 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 /* @test 25 * @bug 8195160 26 * @summary Check blocking of select and close 27 * @requires (os.family == "linux") 28 * @library .. /test/lib 29 * @build RsocketTest 30 * @run main/othervm -Djava.net.preferIPv4Stack=true SelectAndClose 31 */ 32 33 import java.io.IOException; 34 import java.lang.management.ManagementFactory; 35 import java.lang.management.MonitorInfo; 36 import java.lang.management.ThreadInfo; 37 import java.nio.channels.Selector; 38 import jdk.net.Sockets; 39 40 public class SelectAndClose { 41 static Selector selector; 42 static volatile boolean awakened = false; 43 44 private static boolean mightHoldLock(Thread t, Object lock) { 45 long tid = t.getId(); 46 int hash = System.identityHashCode(lock); 47 ThreadInfo ti = ManagementFactory.getThreadMXBean(). 48 getThreadInfo(new long[]{ tid} , true, false, 100)[0]; 49 if (ti != null) { 50 for (MonitorInfo mi : ti.getLockedMonitors()) { 51 if (mi.getIdentityHashCode() == hash) 52 return true; 53 } 54 } 55 return false; 56 } 57 58 public static void main(String[] args) throws Exception { 59 if (!RsocketTest.isRsocketAvailable()) 60 return; 61 62 selector = Sockets.openRdmaSelector(); 63 64 // Create and start a selector in a separate thread. 65 Thread selectThread = new Thread(new Runnable() { 66 public void run() { 67 try { 68 selector.select(); 69 awakened = true; 70 } catch (IOException e) { 71 e.printStackTrace(); 72 throw new RuntimeException("Select did not awaken!"); 73 } 74 } 75 }); 76 selectThread.start(); 77 78 // Spin until the monitor of the selected-key set is likely held 79 // as selected operations are specified to synchronize on the 80 // selected-key set. 81 while (!mightHoldLock(selectThread, selector.selectedKeys())) { 82 Thread.sleep(50); 83 } 84 85 // Close the selector. 86 selector.close(); 87 88 if (!awakened) 89 selector.wakeup(); 90 91 // Wait for select() thread to finish. 92 selectThread.join(); 93 94 if (!awakened) { 95 throw new RuntimeException("Select did not awaken!"); 96 } 97 } 98 }