jdk/test/hotspot/jtreg/gc/g1/TestVerificationInConcurrentCycle.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 */

package gc.g1;

import java.lang.ref.Reference;

/*
 * @test TestVerificationInConcurrentCycle
 * @requires vm.gc.G1
 * @requires vm.debug
 * @summary Basic testing of various GC pause verification during the G1 concurrent cycle.
 * @library /test/lib
 * @build jdk.test.whitebox.WhiteBox
 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 * @run main/othervm
 *   -Xbootclasspath/a:.
 *   -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
 *   -XX:G1HeapRegionSize=2m
 *   -XX:+VerifyBeforeGC -XX:+VerifyDuringGC -XX:+VerifyAfterGC
 *   -XX:+UseG1GC -XX:+G1VerifyHeapRegionCodeRoots
 *   -XX:+G1VerifyBitmaps
 *   gc.g1.TestVerificationInConcurrentCycle
 */

/*
 * @test TestVerificationInConcurrentCycle
 * @requires vm.gc.G1
 * @requires !vm.debug
 * @summary Basic testing of various GC pause verification during the G1 concurrent cycle. It leaves
 *          out G1VerifyBitmaps as this is a debug-only option.
 * @library /test/lib
 * @build jdk.test.whitebox.WhiteBox
 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 * @run main/othervm
 *   -Xbootclasspath/a:.
 *   -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI
 *   -XX:G1HeapRegionSize=2m
 *   -XX:+VerifyBeforeGC -XX:+VerifyDuringGC -XX:+VerifyAfterGC
 *   -XX:+UseG1GC -XX:+G1VerifyHeapRegionCodeRoots
 *   gc.g1.TestVerificationInConcurrentCycle
 */

import jdk.test.whitebox.WhiteBox;
import jdk.test.whitebox.gc.GC;

public class TestVerificationInConcurrentCycle {

    private static final WhiteBox WB = WhiteBox.getWhiteBox();

    private static Object[] allocateHumongous() {
        Object[] result = new Object[7];
        for (int i = 0; i < result.length; i++) {
            result[i] = new byte[1024 * 1024]; // Is humongous.
        }
        return result;
    }

    private static void dropHalf(Object[] array) {
        for (int i = 0; i < array.length; i++) {
            if (i % 2 == 0) {
                array[i] = null;
            }
        }
    }
    // All testN() assume initial state is idle, and restore that state.

    private static void testFullGCAt(String at) throws Exception {
        System.out.println("testSimpleCycle");

        Object[] objects = allocateHumongous();
        try {
            // Run one cycle.
            WB.concurrentGCRunTo(at);
            dropHalf(objects);
            WB.fullGC();
        } finally {
            WB.concurrentGCRunToIdle();
            Reference.reachabilityFence(objects);
        }
    }

    private static void testYoungGCAt(String at) throws Exception {
        System.out.println("testSimpleCycle");

        Object[] objects = allocateHumongous();
        try {
            // Run one cycle.
            WB.concurrentGCRunTo(at);
            dropHalf(objects);
            WB.youngGC();
        } finally {
            WB.concurrentGCRunToIdle();
            Reference.reachabilityFence(objects);
        }
    }

    private static void testGCAt(String at) throws Exception {
        testYoungGCAt(at);
        testFullGCAt(at);
    }

    private static void test() throws Exception {
        try {
            System.out.println("taking control");
            WB.concurrentGCAcquireControl();
            testGCAt(WB.AFTER_MARKING_STARTED);
            testGCAt(WB.BEFORE_MARKING_COMPLETED);
            testGCAt(WB.G1_AFTER_REBUILD_STARTED);
            testGCAt(WB.G1_BEFORE_REBUILD_COMPLETED);
            testGCAt(WB.G1_AFTER_CLEANUP_STARTED);
            testGCAt(WB.G1_BEFORE_CLEANUP_COMPLETED);
        } finally {
            System.out.println("releasing control");
            WB.concurrentGCReleaseControl();
        }
    }

    public static void main(String[] args) throws Exception {
        if (!WB.supportsConcurrentGCBreakpoints()) {
            throw new RuntimeException("G1 should support GC breakpoints");
        }
        test();
    }
}