/******************************************************************************
*
* Copyright © International Business Machines Corp., 2006, 2008
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* NAME
* lookup_pi_state.c
*
* DESCRIPTION
* A test to reproduce a bug in lookup_pi_state()
*
* USAGE:
* Use run_auto.sh script in current directory to build and run test.
*
* AUTHOR
* Darren Hart <dvhltc@us.ibm.com>
*
* HISTORY
* 2006-May-18: Initial version by Darren Hart <dvhltc@us.ibm.com>
*
*****************************************************************************/
#include <stdio.h>
#include <librttest.h>
#define NUM_SLAVES 20
#define SLAVE_PRIO 89
pthread_mutex_t MM;
pthread_mutex_t MS;
pthread_mutex_t MT;
pthread_cond_t CM;
pthread_cond_t CS;
pthread_cond_t CT;
atomic_t slave_order_a = { 0 };
atomic_t slave_order_b = { 0 };
atomic_t slave_order_c = { 0 };
void usage(void)
{
rt_help();
printf("lookup_pi_state specific options:\n");
}
int parse_args(int c, char *v)
{
int handled = 1;
switch (c) {
case 'h':
usage();
exit(0);
default:
handled = 0;
break;
}
return handled;
}
void *slave_thread(void *arg)
{
struct thread *t = (struct thread *)arg;
int id = (intptr_t) t->arg;
// 3
pthread_mutex_lock(&MS);
// 4,5
if (atomic_inc(&slave_order_a) == NUM_SLAVES) {
printf("Slave thread %d notifying master\n", id);
pthread_mutex_lock(&MM); // make sure the master thread is waiting
pthread_cond_signal(&CM);
pthread_mutex_unlock(&MM);
}
printf("Slave thread %d waiting on CS,MS\n", id);
pthread_cond_wait(&CS, &MS); // docs are contradictory on if this
// should be MS or MM
if (atomic_inc(&slave_order_b) <= 6) {
// 10,11
;
// do nothing, just terminate
} else {
// 12
pthread_cond_wait(&CS, &MS);
// 17
}
pthread_mutex_unlock(&MS);
atomic_inc(&slave_order_c);
printf("Slave thread %d terminating\n", id);
return NULL;
}
void *master_thread(void *arg)
{
int i;
struct timespec ts_abs_timeout;
struct thread *t = (struct thread *)arg;
// 1
pthread_mutex_lock(&MM);
for (i = 0; i < NUM_SLAVES; i++) {
create_fifo_thread(slave_thread, (void *)(intptr_t) i,
SLAVE_PRIO);
}
// 2
printf("Master waiting till slaves wait()\n");
pthread_cond_wait(&CM, &MM);
printf("Master awoken\n");
// 6
pthread_mutex_lock(&MS);
// 7
printf("Master doing 3 signals\n");
pthread_cond_signal(&CS);
pthread_cond_signal(&CS);
pthread_cond_signal(&CS);
// 8
printf("Master doing 3 broadcasts\n");
pthread_cond_broadcast(&CS);
pthread_cond_broadcast(&CS);
pthread_cond_broadcast(&CS);
/* if we should timedwait on MS, then we don't need to unlock it here */
pthread_mutex_unlock(&MS);
printf("Master waiting 10 seconds\n");
clock_gettime(CLOCK_REALTIME, &ts_abs_timeout);
ts_abs_timeout.tv_sec += 10;
/*
* docs say CS and MS, but that doesn't seem correct
*
* XXX (garrcoop): then that's a documentation or implementation bug.
* Duh... FIX IT!
*/
pthread_cond_timedwait(&CM, &MM, &ts_abs_timeout);
// 13
pthread_mutex_unlock(&MM);
// 14
printf("Master doing notify of all remaining slaves\n");
pthread_mutex_lock(&MS);
pthread_cond_broadcast(&CS);
// 15
/*
* docs say MM, but that doesn't make sense..
*
* XXX (garrcoop): comments above apply here too
*/
pthread_mutex_unlock(&MS);
// 16
pthread_mutex_lock(&MT);
clock_gettime(CLOCK_REALTIME, &ts_abs_timeout);
ts_abs_timeout.tv_sec += 2;
pthread_cond_timedwait(&CT, &MT, &ts_abs_timeout);
// 18
while (!thread_quit(t))
usleep(10);
printf("All slaves have terminated\n");
return NULL;
}
int main(int argc, char *argv[])
{
init_pi_mutex(&MM);
init_pi_mutex(&MS);
init_pi_mutex(&MT);
setup();
pthread_cond_init(&CM, NULL);
pthread_cond_init(&CS, NULL);
pthread_cond_init(&CT, NULL);
rt_init("h", parse_args, argc, argv);
create_other_thread(master_thread, NULL);
/* wait for the slaves to quit */
while (atomic_get(&slave_order_c) < NUM_SLAVES)
usleep(10);
join_threads();
return 0;
}