File: ZeroCoreThreads.java

package info (click to toggle)
openjdk-11 11.0.4%2B11-1
  • links: PTS, VCS
  • area: main
  • in suites: sid
  • size: 757,028 kB
  • sloc: java: 5,016,041; xml: 1,191,974; cpp: 934,731; ansic: 555,697; sh: 24,299; objc: 12,703; python: 3,602; asm: 3,415; makefile: 2,772; awk: 351; sed: 172; perl: 114; jsp: 24; csh: 3
file content (142 lines) | stat: -rw-r--r-- 5,467 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
/*
 * 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.
 */

/*
 * 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 Martin Buchholz 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 8022642 8065320 8129861
 * @summary Ensure relative sanity when zero core threads
 * @library /lib/testlibrary/
 * @modules java.base/java.util.concurrent:open
 */

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

import java.lang.reflect.Field;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;
import java.util.function.BooleanSupplier;
import jdk.testlibrary.Utils;

public class ZeroCoreThreads {
    static final long LONG_DELAY_MS = Utils.adjustTimeout(10_000);

    static long millisElapsedSince(long startTime) {
        return (System.nanoTime() - startTime) / (1000L * 1000L);
    }

    static void spinWaitUntil(BooleanSupplier predicate, long timeoutMillis) {
        long startTime = -1L;
        while (!predicate.getAsBoolean()) {
            if (startTime == -1L)
                startTime = System.nanoTime();
            else if (millisElapsedSince(startTime) > timeoutMillis)
                throw new AssertionError(
                    String.format("timed out after %s ms", timeoutMillis));
            Thread.yield();
        }
    }

    static boolean hasWaiters(ReentrantLock lock, Condition condition) {
        lock.lock();
        try {
            return lock.hasWaiters(condition);
        } finally {
            lock.unlock();
        }
    }

    static void awaitHasWaiters(ReentrantLock lock, Condition condition,
                                long timeoutMillis) {
        spinWaitUntil(() -> hasWaiters(lock, condition), timeoutMillis);
    }

    static <T> T getField(Object x, String fieldName) {
        try {
            Field field = x.getClass().getDeclaredField(fieldName);
            field.setAccessible(true);
            return (T) field.get(x);
        } catch (ReflectiveOperationException ex) {
            throw new AssertionError(ex);
        }
    }

    void test(String[] args) throws Throwable {
        ScheduledThreadPoolExecutor p = new ScheduledThreadPoolExecutor(0);
        try {
            test(p);
        } finally {
            p.shutdownNow();
            check(p.awaitTermination(LONG_DELAY_MS, MILLISECONDS));
        }
    }

    void test(ScheduledThreadPoolExecutor p) throws Throwable {
        Runnable dummy = new Runnable() { public void run() {
            throw new AssertionError("shouldn't get here"); }};
        BlockingQueue q = p.getQueue();
        ReentrantLock lock = getField(q, "lock");
        Condition available = getField(q, "available");

        equal(0, p.getPoolSize());
        equal(0, p.getLargestPoolSize());
        equal(0L, p.getTaskCount());
        equal(0L, p.getCompletedTaskCount());
        p.schedule(dummy, 1L, HOURS);
        // Ensure one pool thread actually waits in timed queue poll
        awaitHasWaiters(lock, available, LONG_DELAY_MS);
        equal(1, p.getPoolSize());
        equal(1, p.getLargestPoolSize());
        equal(1L, p.getTaskCount());
        equal(0L, p.getCompletedTaskCount());
    }

    //--------------------- Infrastructure ---------------------------
    volatile int passed = 0, failed = 0;
    void pass() {passed++;}
    void fail() {failed++; Thread.dumpStack();}
    void fail(String msg) {System.err.println(msg); fail();}
    void unexpected(Throwable t) {failed++; t.printStackTrace();}
    void check(boolean cond) {if (cond) pass(); else fail();}
    void equal(Object x, Object y) {
        if (x == null ? y == null : x.equals(y)) pass();
        else fail(x + " not equal to " + y);}
    public static void main(String[] args) throws Throwable {
        new ZeroCoreThreads().instanceMain(args);}
    void instanceMain(String[] args) throws Throwable {
        try {test(args);} catch (Throwable t) {unexpected(t);}
        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
        if (failed > 0) throw new AssertionError("Some tests failed");}
}