YieldFewNanosTest.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * version 2 for more details (a copy is included in the LICENSE file that
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/*
 * @test
 * @library /lib/testlibrary
 * @summary Verify park not happened for a very small interval
 * @requires os.family == "linux"
 * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+UseWisp2 YieldFewNanosTest
 */

import com.alibaba.wisp.engine.WispEngine;

import sun.misc.SharedSecrets;

import java.lang.reflect.Method;
import java.util.concurrent.Executors;
import java.util.concurrent.locks.LockSupport;

import static jdk.testlibrary.Asserts.assertTrue;

public class YieldFewNanosTest {
    public static void main(String[] args) throws Exception {
        assertTrue(Executors.newSingleThreadExecutor().submit(() -> {
            long pc = (long) new YieldEmptyQueueTest.ObjAccess(SharedSecrets.getJavaLangAccess().getWispTask(Thread.currentThread()))
                    .ref("carrier").ref("counter").ref("parkCount").obj;
            LockSupport.parkNanos(1);
            return (long) new YieldEmptyQueueTest.ObjAccess(SharedSecrets.getJavaLangAccess().getWispTask(Thread.currentThread()))
                    .ref("carrier").ref("counter").ref("parkCount").obj == pc;
        }).get());
    }
}