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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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
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/*
 * @test HandshakeWalkOneExitTest
 * @summary This test tries to stress the handshakes with new and exiting threads
 * @library /testlibrary /test/lib
 * @build HandshakeWalkOneExitTest
 * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI HandshakeWalkOneExitTest
 */

import jdk.test.lib.Asserts;
import jdk.test.whitebox.WhiteBox;

public class HandshakeWalkOneExitTest  implements Runnable {

    @Override
    public void run() {
    }

    static volatile boolean exit_now = false;
    static Thread[] threads;

    public static void main(String... args) throws Exception {
        int testRuns = 20;
        int testThreads = 128;

        HandshakeWalkOneExitTest test = new HandshakeWalkOneExitTest();

        Runnable hser = new Runnable(){
            public void run(){
                WhiteBox wb = WhiteBox.getWhiteBox();
                while(!exit_now) {
                    Thread[] t = threads;
                    for (int i = 0; i<t.length ; i++) {
                        wb.handshakeWalkStack(t[i], false);
                    }
                }
            }
        };
        Thread hst = new Thread(hser);
        for (int k = 0; k<testRuns ; k++) {
            threads = new Thread[testThreads];
            for (int i = 0; i<threads.length ; i++) {
                threads[i] = new Thread(test);
                threads[i].start();
            }
            if (k == 0) {
                hst.start();
            }
        }
        exit_now = true;
        hst.join();
    }
}