view test/runtime/contended/Inheritance1.java @ 10374:87c64c0438fb

6976350: G1: deal with fragmentation while copying objects during GC Summary: Create G1ParGCAllocBufferContainer to contain two buffers instead of previously using one buffer, in order to hold the first priority buffer longer. Thus, when some large objects hits the value of free space left in the first priority buffer it has an alternative to fit in the second priority buffer while the first priority buffer is given more chances to try allocating smaller objects. Overall, it will improve heap space efficiency. Reviewed-by: johnc, jmasa, brutisso Contributed-by: tamao <tao.mao@oracle.com>
author tamao
date Mon, 03 Jun 2013 14:37:13 -0700
parents 205dd30230e1
children
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/*
 * Copyright (c) 2013, 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.
 */

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.lang.Class;
import java.lang.String;
import java.lang.System;
import java.lang.management.ManagementFactory;
import java.lang.management.RuntimeMXBean;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CyclicBarrier;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import sun.misc.Unsafe;
import sun.misc.Contended;

/*
 * @test
 * @bug     8012939
 * @summary \@Contended doesn't work correctly with inheritance
 *
 * @run main/othervm -XX:-RestrictContended Inheritance1
 */
public class Inheritance1 {

    private static final Unsafe U;
    private static int ADDRESS_SIZE;
    private static int HEADER_SIZE;

    static {
        // steal Unsafe
        try {
            Field unsafe = Unsafe.class.getDeclaredField("theUnsafe");
            unsafe.setAccessible(true);
            U = (Unsafe) unsafe.get(null);
        } catch (NoSuchFieldException | IllegalAccessException e) {
            throw new IllegalStateException(e);
        }

        // When running with CompressedOops on 64-bit platform, the address size
        // reported by Unsafe is still 8, while the real reference fields are 4 bytes long.
        // Try to guess the reference field size with this naive trick.
        try {
            long off1 = U.objectFieldOffset(CompressedOopsClass.class.getField("obj1"));
            long off2 = U.objectFieldOffset(CompressedOopsClass.class.getField("obj2"));
            ADDRESS_SIZE = (int) Math.abs(off2 - off1);
            HEADER_SIZE = (int) Math.min(off1, off2);
        } catch (NoSuchFieldException e) {
            ADDRESS_SIZE = -1;
        }
    }

    static class CompressedOopsClass {
        public Object obj1;
        public Object obj2;
    }

    public static boolean arePaddedPairwise(Class klass, String field1, String field2) throws Exception {
        Field f1 = klass.getField(field1);
        Field f2 = klass.getField(field2);

        int diff = offset(f1) - offset(f2);
        if (diff < 0) {
            // f1 is first
            return (offset(f2) - (offset(f1) + getSize(f1))) > 64;
        } else {
            // f2 is first
            return (offset(f1) - (offset(f2) + getSize(f2))) > 64;
        }
    }

    public static boolean sameLayout(Class klass1, Class klass2) throws Exception {
        for (Field f1 : klass1.getDeclaredFields()) {
            Field f2 = klass2.getDeclaredField(f1.getName());
            if (offset(f1) != offset(f2)) {
                return false;
            }
        }

        for (Field f2 : klass1.getDeclaredFields()) {
            Field f1 = klass2.getDeclaredField(f2.getName());
            if (offset(f1) != offset(f2)) {
                return false;
            }
        }

        return true;
    }

    public static boolean isStatic(Field field) {
        return Modifier.isStatic(field.getModifiers());
    }

    public static int offset(Field field) {
        if (isStatic(field)) {
            return (int) U.staticFieldOffset(field);
        } else {
            return (int) U.objectFieldOffset(field);
        }
    }

    public static int getSize(Field field) {
        Class type = field.getType();
        if (type == byte.class)    { return 1; }
        if (type == boolean.class) { return 1; }
        if (type == short.class)   { return 2; }
        if (type == char.class)    { return 2; }
        if (type == int.class)     { return 4; }
        if (type == float.class)   { return 4; }
        if (type == long.class)    { return 8; }
        if (type == double.class)  { return 8; }
        return ADDRESS_SIZE;
    }

    public static void main(String[] args) throws Exception {
        boolean endResult = true;

        // --------------- INSTANCE FIELDS ---------------------

        if (!arePaddedPairwise(A2_R1.class, "int1", "int2")) {
            System.err.println("A2_R1 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A3_R1.class, "int1", "int2")) {
            System.err.println("A3_R1 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A1_R2.class, "int1", "int2")) {
            System.err.println("A1_R2 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A2_R2.class, "int1", "int2")) {
            System.err.println("A2_R2 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A3_R2.class, "int1", "int2")) {
            System.err.println("A3_R2 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A1_R3.class, "int1", "int2")) {
            System.err.println("A1_R3 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A2_R3.class, "int1", "int2")) {
            System.err.println("A2_R3 failed");
            endResult &= false;
        }

        if (!arePaddedPairwise(A3_R3.class, "int1", "int2")) {
            System.err.println("A3_R3 failed");
            endResult &= false;
        }

        System.out.println(endResult ? "Test PASSES" : "Test FAILS");
        if (!endResult) {
           throw new Error("Test failed");
        }
    }

    public static class R1 {
        public int int1;
    }

    public static class R2 {
        @Contended
        public int int1;
    }

    @Contended
    public static class R3 {
        public int int1;
    }

    public static class A1_R1 extends R1 {
        public int int2;
    }

    public static class A2_R1 extends R1 {
        @Contended
        public int int2;
    }

    @Contended
    public static class A3_R1 extends R1 {
        public int int2;
    }

    public static class A1_R2 extends R2 {
        public int int2;
    }

    public static class A2_R2 extends R2 {
        @Contended
        public int int2;
    }

    @Contended
    public static class A3_R2 extends R2 {
        public int int2;
    }

    public static class A1_R3 extends R3 {
        public int int2;
    }

    public static class A2_R3 extends R3 {
        @Contended
        public int int2;
    }

    @Contended
    public static class A3_R3 extends R3 {
        public int int2;
    }


}