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
|
/*
* Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
* 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.
*
*/
/*
* @test HandshakeSuspendExitTest
* @summary This test tries to stress the handshakes with new and exiting threads while suspending them.
* @library /testlibrary /test/lib
* @build HandshakeSuspendExitTest
* @run main/othervm -XX:+UnlockDiagnosticVMOptions -XX:GuaranteedSafepointInterval=1 -XX:+HandshakeALot HandshakeSuspendExitTest
*/
public class HandshakeSuspendExitTest implements Runnable {
static Thread[] _suspend_threads = new Thread[16];
static volatile boolean _exit_now = false;
static java.util.concurrent.Semaphore _sem = new java.util.concurrent.Semaphore(0);
@Override
public void run() {
_sem.release();
while (!_exit_now) {
// Leave last 2 threads running.
for (int i = 0; i < _suspend_threads.length - 2; i++) {
if (Thread.currentThread() != _suspend_threads[i]) {
_suspend_threads[i].suspend();
_suspend_threads[i].resume();
}
}
}
_sem.release();
}
public static void main(String... args) throws Exception {
HandshakeSuspendExitTest test = new HandshakeSuspendExitTest();
// Fire-up suspend threads.
for (int i = 0; i < _suspend_threads.length; i++) {
_suspend_threads[i] = new Thread(test);
}
for (int i = 0; i < _suspend_threads.length; i++) {
_suspend_threads[i].start();
}
// Wait for all suspend-threads to start looping.
for (Thread thr : _suspend_threads) {
_sem.acquire();
}
// Fire-up exiting threads.
Thread[] exit_threads = new Thread[128];
for (int i = 0; i < exit_threads.length; i++) {
exit_threads[i] = new Thread();
exit_threads[i].start();
}
// Try to suspend them.
for (Thread thr : exit_threads) {
thr.suspend();
}
for (Thread thr : exit_threads) {
thr.resume();
}
// Start exit and join.
_exit_now = true;
int waiting = _suspend_threads.length;
do {
// Resume any worker threads that might have suspended
// each other at exactly the same time so they can see
// _exit_now and check in via the semaphore.
for (Thread thr : _suspend_threads) {
thr.resume();
}
while (_sem.tryAcquire()) {
--waiting;
}
} while (waiting > 0);
for (Thread thr : _suspend_threads) {
thr.join();
}
for (Thread thr : exit_threads) {
thr.join();
}
}
}
|
