1 /*
   2  * Copyright (c) 2016, 2018, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 /*
  25  * Run standalone with: --add-exports java.base/jdk.internal.misc=ALL-UNNAMED --add-opens java.base/jdk.internal.misc=ALL-UNNAMED
  26  */
  27 
  28 /*
  29  * @test TestReferenceCAS
  30  * @summary Shenandoah reference CAS test
  31  * @key gc
  32  * @requires vm.gc.Shenandoah & !vm.graal.enabled
  33  * @modules java.base/jdk.internal.misc:+open
  34  *
  35  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC                                                 TestReferenceCAS
  36  * @run main/othervm -Diters=100   -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -Xint                                           TestReferenceCAS
  37  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:-TieredCompilation                          TestReferenceCAS
  38  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:TieredStopAtLevel=1                         TestReferenceCAS
  39  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:TieredStopAtLevel=4                         TestReferenceCAS
  40  */
  41 
  42 /*
  43  * @test TestReferenceCAS
  44  * @summary Shenandoah reference CAS test
  45  * @key gc
  46  * @requires vm.gc.Shenandoah & !vm.graal.enabled & (vm.bits == "64")
  47  * @modules java.base/jdk.internal.misc:+open
  48  *
  49  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:-UseCompressedOops                          TestReferenceCAS
  50  * @run main/othervm -Diters=100   -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:-UseCompressedOops -Xint                    TestReferenceCAS
  51  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:-UseCompressedOops -XX:-TieredCompilation   TestReferenceCAS
  52  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:-UseCompressedOops -XX:TieredStopAtLevel=1  TestReferenceCAS
  53  * @run main/othervm -Diters=20000 -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:ShenandoahGCHeuristics=aggressive -XX:+UseShenandoahGC -XX:-UseCompressedOops -XX:TieredStopAtLevel=4  TestReferenceCAS
  54  */
  55 
  56 import java.lang.reflect.Field;
  57 
  58 public class TestReferenceCAS {
  59 
  60     static final int ITERS = Integer.getInteger("iters", 1);
  61     static final int WEAK_ATTEMPTS = Integer.getInteger("weakAttempts", 10);
  62 
  63     static final jdk.internal.misc.Unsafe UNSAFE;
  64     static final long V_OFFSET;
  65 
  66     static {
  67         try {
  68             Field f = jdk.internal.misc.Unsafe.class.getDeclaredField("theUnsafe");
  69             f.setAccessible(true);
  70             UNSAFE = (jdk.internal.misc.Unsafe) f.get(null);
  71         } catch (Exception e) {
  72             throw new RuntimeException("Unable to get Unsafe instance.", e);
  73         }
  74 
  75         try {
  76             Field vField = TestReferenceCAS.class.getDeclaredField("v");
  77             V_OFFSET = UNSAFE.objectFieldOffset(vField);
  78         } catch (Exception e) {
  79             throw new RuntimeException(e);
  80         }
  81     }
  82 
  83     Object v;
  84 
  85     private static void assertEquals(boolean a, boolean b, String msg) {
  86         if (a != b) {
  87             throw new RuntimeException("a (" + a + ") != b (" + b + "): " + msg);
  88         }
  89     }
  90 
  91     private static void assertEquals(Object a, Object b, String msg) {
  92         if (!a.equals(b)) {
  93             throw new RuntimeException("a (" + a.toString() + ") != b (" + b.toString() + "): " + msg);
  94         }
  95     }
  96 
  97     public static void main(String[] args) {
  98         TestReferenceCAS t = new TestReferenceCAS();
  99         for (int c = 0; c < ITERS; c++) {
 100             testAccess(t, V_OFFSET);
 101         }
 102     }
 103 
 104     static void testAccess(Object base, long offset) {
 105         String foo = new String("foo");
 106         String bar = new String("bar");
 107         String baz = new String("baz");
 108         UNSAFE.putReference(base, offset, "foo");
 109         {
 110             String newval = bar;
 111             boolean r = UNSAFE.compareAndSetReference(base, offset, "foo", newval);
 112             assertEquals(r, true, "success compareAndSet Object");
 113             assertEquals(newval, "bar", "must not destroy newval");
 114             Object x = UNSAFE.getReference(base, offset);
 115             assertEquals(x, "bar", "success compareAndSet Object value");
 116         }
 117 
 118         {
 119             String newval = baz;
 120             boolean r = UNSAFE.compareAndSetReference(base, offset, "foo", newval);
 121             assertEquals(r, false, "failing compareAndSet Object");
 122             assertEquals(newval, "baz", "must not destroy newval");
 123             Object x = UNSAFE.getReference(base, offset);
 124             assertEquals(x, "bar", "failing compareAndSet Object value");
 125         }
 126 
 127         UNSAFE.putReference(base, offset, "bar");
 128         {
 129             String newval = foo;
 130             Object r = UNSAFE.compareAndExchangeReference(base, offset, "bar", newval);
 131             assertEquals(r, "bar", "success compareAndExchange Object");
 132             assertEquals(newval, "foo", "must not destroy newval");
 133             Object x = UNSAFE.getReference(base, offset);
 134             assertEquals(x, "foo", "success compareAndExchange Object value");
 135         }
 136 
 137         {
 138             String newval = baz;
 139             Object r = UNSAFE.compareAndExchangeReference(base, offset, "bar", newval);
 140             assertEquals(r, "foo", "failing compareAndExchange Object");
 141             assertEquals(newval, "baz", "must not destroy newval");
 142             Object x = UNSAFE.getReference(base, offset);
 143             assertEquals(x, "foo", "failing compareAndExchange Object value");
 144         }
 145 
 146         UNSAFE.putReference(base, offset, "bar");
 147         {
 148             String newval = foo;
 149             boolean success = false;
 150             for (int c = 0; c < WEAK_ATTEMPTS && !success; c++) {
 151                 success = UNSAFE.weakCompareAndSetReference(base, offset, "bar", newval);
 152                 assertEquals(newval, "foo", "must not destroy newval");
 153             }
 154             assertEquals(success, true, "weakCompareAndSet Object");
 155             Object x = UNSAFE.getReference(base, offset);
 156             assertEquals(x, "foo", "weakCompareAndSet Object");
 157         }
 158     }
 159 
 160 }