/*

 * 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

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 */

/*

 * This file is available under and governed by the GNU General Public

 * License version 2 only, as published by the Free Software Foundation.

 * However, the following notice accompanied the original version of this

 * file:

 *

 * Written by Doug Lea with assistance from members of JCP JSR-166

 * Expert Group and released to the public domain, as explained at

 * http://creativecommons.org/publicdomain/zero/1.0/

 */

/*

 * @test

 * @bug 4486658 5031862 8140471

 * @summary Checks for responsiveness of locks to timeouts.

 * @library /test/lib

 */

import static java.util.concurrent.TimeUnit.MILLISECONDS;

import java.util.concurrent.CyclicBarrier;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.ThreadLocalRandom;

import java.util.concurrent.TimeUnit;

import java.util.concurrent.locks.ReentrantLock;

import jdk.test.lib.Utils;

public final class TimeoutLockLoops {

    static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);

    static final ExecutorService pool = Executors.newCachedThreadPool();

    static boolean print = false;

    static final long TIMEOUT = 10;

    public static void main(String[] args) throws Exception {

        int maxThreads = 8;

        if (args.length > 0)

            maxThreads = Integer.parseInt(args[0]);

        print = true;

        for (int i = 1; i <= maxThreads; i += (i+1) >>> 1) {

            System.out.print("Threads: " + i);

            new ReentrantLockLoop(i).test();

        }

        pool.shutdown();

        if (! pool.awaitTermination(LONG_DELAY_MS, MILLISECONDS))

            throw new Error();

    }

    static final class ReentrantLockLoop implements Runnable {

        private int v = ThreadLocalRandom.current().nextInt();

        private volatile int result = 17;

        private final ReentrantLock lock = new ReentrantLock();

        private final LoopHelpers.BarrierTimer timer = new LoopHelpers.BarrierTimer();

        private final CyclicBarrier barrier;

        private final int nthreads;

        private volatile Throwable fail = null;

        ReentrantLockLoop(int nthreads) {

            this.nthreads = nthreads;

            barrier = new CyclicBarrier(nthreads+1, timer);

        }

        final void test() throws Exception {

            for (int i = 0; i < nthreads; ++i) {

                lock.lock();

                pool.execute(this);

                lock.unlock();

            }

            barrier.await();

            Thread.sleep(ThreadLocalRandom.current().nextInt(5));

            while (!lock.tryLock()); // Jam lock

            //            lock.lock();

            barrier.await();

            if (print) {

                long time = timer.getTime();

                System.out.println("\t " + secs + "s run time");

            }

            int r = result;

            if (r == 0) // avoid overoptimization

                System.out.println("useless result: " + r);

            if (fail != null) throw new RuntimeException(fail);

        }

        public final void run() {

            try {

                barrier.await();

                int sum = v;

                int x = 17;

                final ReentrantLock lock = this.lock;

                while (lock.tryLock(TIMEOUT, TimeUnit.MILLISECONDS)) {

                    try {

                        v = x = LoopHelpers.compute1(v);

                    }

                    finally {

                        lock.unlock();

                    }

                    sum += LoopHelpers.compute2(x);

                }

                barrier.await();

                result += sum;

            }

            catch (Throwable ex) {

                fail = ex;

                throw new RuntimeException(ex);

            }

        }

    }

}