1/******************************************************************************
2 *
3 *	 Copyright © International Business Machines	Corp., 2006, 2008
4 *
5 *	 This program is free software;	you can redistribute it and/or modify
6 *	 it under the terms of the GNU General Public License as published by
7 *	 the Free Software Foundation; either version 2 of the License, or
8 *	 (at your option) any later version.
9 *
10 *	 This program is distributed in the hope that it will be useful,
11 *	 but WITHOUT ANY WARRANTY;	without even the implied warranty of
12 *	 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See
13 *	 the GNU General Public License for more details.
14 *
15 *	 You should have received a copy of the GNU General Public License
16 *	 along with this program;	if not, write to the Free Software
17 *	 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * NAME
20 *			lookup_pi_state.c
21 *
22 * DESCRIPTION
23 *			 A test to reproduce a bug in lookup_pi_state()
24 *
25 * USAGE:
26 *			Use run_auto.sh script in current directory to build and run test.
27 *
28 * AUTHOR
29 *			Darren Hart <dvhltc@us.ibm.com>
30 *
31 * HISTORY
32 *  2006-May-18:	Initial version by Darren Hart <dvhltc@us.ibm.com>
33 *
34 *****************************************************************************/
35
36#include <stdio.h>
37#include <librttest.h>
38
39#define NUM_SLAVES 20
40#define SLAVE_PRIO 89
41
42pthread_mutex_t MM;
43pthread_mutex_t MS;
44pthread_mutex_t MT;
45pthread_cond_t CM;
46pthread_cond_t CS;
47pthread_cond_t CT;
48
49atomic_t slave_order_a = { 0 };
50atomic_t slave_order_b = { 0 };
51atomic_t slave_order_c = { 0 };
52
53void usage(void)
54{
55	rt_help();
56	printf("lookup_pi_state specific options:\n");
57}
58
59int parse_args(int c, char *v)
60{
61
62	int handled = 1;
63	switch (c) {
64	case 'h':
65		usage();
66		exit(0);
67	default:
68		handled = 0;
69		break;
70	}
71	return handled;
72}
73
74void *slave_thread(void *arg)
75{
76	struct thread *t = (struct thread *)arg;
77	int id = (intptr_t) t->arg;
78// 3
79	pthread_mutex_lock(&MS);
80// 4,5
81	if (atomic_inc(&slave_order_a) == NUM_SLAVES) {
82		printf("Slave thread %d notifying master\n", id);
83		pthread_mutex_lock(&MM);	// make sure the master thread is waiting
84		pthread_cond_signal(&CM);
85		pthread_mutex_unlock(&MM);
86	}
87	printf("Slave thread %d waiting on CS,MS\n", id);
88	pthread_cond_wait(&CS, &MS);	// docs are contradictory on if this
89	// should be MS or MM
90
91	if (atomic_inc(&slave_order_b) <= 6) {
92// 10,11
93		;
94		// do nothing, just terminate
95	} else {
96// 12
97		pthread_cond_wait(&CS, &MS);
98// 17
99	}
100	pthread_mutex_unlock(&MS);
101	atomic_inc(&slave_order_c);
102	printf("Slave thread %d terminating\n", id);
103	return NULL;
104}
105
106void *master_thread(void *arg)
107{
108	int i;
109	struct timespec ts_abs_timeout;
110	struct thread *t = (struct thread *)arg;
111// 1
112	pthread_mutex_lock(&MM);
113	for (i = 0; i < NUM_SLAVES; i++) {
114		create_fifo_thread(slave_thread, (void *)(intptr_t) i,
115				   SLAVE_PRIO);
116	}
117// 2
118	printf("Master waiting till slaves wait()\n");
119	pthread_cond_wait(&CM, &MM);
120	printf("Master awoken\n");
121// 6
122	pthread_mutex_lock(&MS);
123// 7
124	printf("Master doing 3 signals\n");
125	pthread_cond_signal(&CS);
126	pthread_cond_signal(&CS);
127	pthread_cond_signal(&CS);
128// 8
129	printf("Master doing 3 broadcasts\n");
130	pthread_cond_broadcast(&CS);
131	pthread_cond_broadcast(&CS);
132	pthread_cond_broadcast(&CS);
133
134	/* if we should timedwait on MS, then we don't need to unlock it here */
135	pthread_mutex_unlock(&MS);
136
137	printf("Master waiting 10 seconds\n");
138	clock_gettime(CLOCK_REALTIME, &ts_abs_timeout);
139	ts_abs_timeout.tv_sec += 10;
140	/*
141	 * docs say CS and MS, but that doesn't seem correct
142	 *
143	 * XXX (garrcoop): then that's a documentation or implementation bug.
144	 * Duh... FIX IT!
145	 */
146	pthread_cond_timedwait(&CM, &MM, &ts_abs_timeout);
147// 13
148	pthread_mutex_unlock(&MM);
149// 14
150	printf("Master doing notify of all remaining slaves\n");
151	pthread_mutex_lock(&MS);
152	pthread_cond_broadcast(&CS);
153// 15
154	/*
155	 * docs say MM, but that doesn't make sense..
156	 *
157	 * XXX (garrcoop): comments above apply here too
158	 */
159	pthread_mutex_unlock(&MS);
160// 16
161	pthread_mutex_lock(&MT);
162	clock_gettime(CLOCK_REALTIME, &ts_abs_timeout);
163	ts_abs_timeout.tv_sec += 2;
164	pthread_cond_timedwait(&CT, &MT, &ts_abs_timeout);
165// 18
166	while (!thread_quit(t))
167		usleep(10);
168
169	printf("All slaves have terminated\n");
170
171	return NULL;
172}
173
174int main(int argc, char *argv[])
175{
176	init_pi_mutex(&MM);
177	init_pi_mutex(&MS);
178	init_pi_mutex(&MT);
179	setup();
180
181	pthread_cond_init(&CM, NULL);
182	pthread_cond_init(&CS, NULL);
183	pthread_cond_init(&CT, NULL);
184
185	rt_init("h", parse_args, argc, argv);
186
187	create_other_thread(master_thread, NULL);
188
189	/* wait for the slaves to quit */
190	while (atomic_get(&slave_order_c) < NUM_SLAVES)
191		usleep(10);
192
193	join_threads();
194
195	return 0;
196}
197