[urcu.git] / tests / benchmark / test_rwlock.c

/*
 * test_urcu.c
 *
 * Userspace RCU library - test program
 *
 * Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * 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.
 */

#include <stdio.h>
#include <pthread.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdio.h>
#include <assert.h>
#include <errno.h>

#include <urcu/arch.h>
#include <urcu/tls-compat.h>
#include "cpuset.h"
#include "thread-id.h"

/* hardcoded number of CPUs */
#define NR_CPUS 16384

#ifndef DYNAMIC_LINK_TEST
#define _LGPL_SOURCE
#endif
#include <urcu.h>

struct test_array {
	int a;
};

/*
 * static rwlock initializer is broken on Cygwin. Use runtime
 * initialization.
 */
pthread_rwlock_t lock;

static volatile int test_go, test_stop;

static unsigned long wdelay;

static volatile struct test_array test_array = { 8 };

static unsigned long duration;

/* read-side C.S. duration, in loops */
static unsigned long rduration;

/* write-side C.S. duration, in loops */
static unsigned long wduration;

static inline void loop_sleep(unsigned long loops)
{
	while (loops-- != 0)
		caa_cpu_relax();
}

static int verbose_mode;

#define printf_verbose(fmt, args...)		\
	do {					\
		if (verbose_mode)		\
			printf(fmt, args);	\
	} while (0)

static unsigned int cpu_affinities[NR_CPUS];
static unsigned int next_aff = 0;
static int use_affinity = 0;

pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;

static void set_affinity(void)
{
#if HAVE_SCHED_SETAFFINITY
	cpu_set_t mask;
	int cpu, ret;
#endif /* HAVE_SCHED_SETAFFINITY */

	if (!use_affinity)
		return;

#if HAVE_SCHED_SETAFFINITY
	ret = pthread_mutex_lock(&affinity_mutex);
	if (ret) {
		perror("Error in pthread mutex lock");
		exit(-1);
	}
	cpu = cpu_affinities[next_aff++];
	ret = pthread_mutex_unlock(&affinity_mutex);
	if (ret) {
		perror("Error in pthread mutex unlock");
		exit(-1);
	}

	CPU_ZERO(&mask);
	CPU_SET(cpu, &mask);
#if SCHED_SETAFFINITY_ARGS == 2
	sched_setaffinity(0, &mask);
#else
	sched_setaffinity(0, sizeof(mask), &mask);
#endif
#endif /* HAVE_SCHED_SETAFFINITY */
}

/*
 * returns 0 if test should end.
 */
static int test_duration_write(void)
{
	return !test_stop;
}

static int test_duration_read(void)
{
	return !test_stop;
}

static DEFINE_URCU_TLS(unsigned long long, nr_writes);
static DEFINE_URCU_TLS(unsigned long long, nr_reads);

static unsigned int nr_readers;
static unsigned int nr_writers;

pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;

void rcu_copy_mutex_lock(void)
{
	int ret;
	ret = pthread_mutex_lock(&rcu_copy_mutex);
	if (ret) {
		perror("Error in pthread mutex lock");
		exit(-1);
	}
}

void rcu_copy_mutex_unlock(void)
{
	int ret;

	ret = pthread_mutex_unlock(&rcu_copy_mutex);
	if (ret) {
		perror("Error in pthread mutex unlock");
		exit(-1);
	}
}

void *thr_reader(void *_count)
{
	unsigned long long *count = _count;

	printf_verbose("thread_begin %s, tid %lu\n",
			"reader", urcu_get_thread_id());

	set_affinity();

	while (!test_go)
	{
	}

	for (;;) {
		int a, ret;

		ret = pthread_rwlock_rdlock(&lock);
		if (ret) {
			fprintf(stderr, "reader pthread_rwlock_rdlock: %s\n", strerror(ret));
			abort();
		}

		a = test_array.a;
		assert(a == 8);
		if (caa_unlikely(rduration))
			loop_sleep(rduration);

		ret = pthread_rwlock_unlock(&lock);
		if (ret) {
			fprintf(stderr, "reader pthread_rwlock_unlock: %s\n", strerror(ret));
			abort();
		}

		URCU_TLS(nr_reads)++;
		if (caa_unlikely(!test_duration_read()))
			break;
	}

	*count = URCU_TLS(nr_reads);

	printf_verbose("thread_end %s, tid %lu, count %llu\n",
			"reader", urcu_get_thread_id(), *count);
	return ((void*)1);

}

void *thr_writer(void *_count)
{
	unsigned long long *count = _count;

	printf_verbose("thread_begin %s, tid %lu\n",
			"writer", urcu_get_thread_id());

	set_affinity();

	while (!test_go)
	{
	}
	cmm_smp_mb();

	for (;;) {
		int ret;

		ret = pthread_rwlock_wrlock(&lock);
		if (ret) {
			fprintf(stderr, "writer pthread_rwlock_wrlock: %s\n", strerror(ret));
			abort();
		}

		test_array.a = 0;
		test_array.a = 8;
		if (caa_unlikely(wduration))
			loop_sleep(wduration);

		ret = pthread_rwlock_unlock(&lock);
		if (ret) {
			fprintf(stderr, "writer pthread_rwlock_unlock: %s\n", strerror(ret));
			abort();
		}

		URCU_TLS(nr_writes)++;
		if (caa_unlikely(!test_duration_write()))
			break;
		if (caa_unlikely(wdelay))
			loop_sleep(wdelay);
	}
	*count = URCU_TLS(nr_writes);

	printf_verbose("thread_end %s, tid %lu, count %llu\n",
			"writer", urcu_get_thread_id(), *count);
	return ((void*)2);
}

void show_usage(int argc, char **argv)
{
	printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
		argv[0]);
	printf("OPTIONS:\n");
	printf("	[-d delay] (writer period (us))\n");
	printf("	[-c duration] (reader C.S. duration (in loops))\n");
	printf("	[-e duration] (writer C.S. duration (in loops))\n");
	printf("	[-v] (verbose output)\n");
	printf("	[-a cpu#] [-a cpu#]... (affinity)\n");
	printf("\n");
}

int main(int argc, char **argv)
{
	int err;
	pthread_t *tid_reader, *tid_writer;
	void *tret;
	unsigned long long *count_reader, *count_writer;
	unsigned long long tot_reads = 0, tot_writes = 0;
	int i, a;

	if (argc < 4) {
		show_usage(argc, argv);
		return -1;
	}
	cmm_smp_mb();

	err = sscanf(argv[1], "%u", &nr_readers);
	if (err != 1) {
		show_usage(argc, argv);
		return -1;
	}

	err = sscanf(argv[2], "%u", &nr_writers);
	if (err != 1) {
		show_usage(argc, argv);
		return -1;
	}
	
	err = sscanf(argv[3], "%lu", &duration);
	if (err != 1) {
		show_usage(argc, argv);
		return -1;
	}

	for (i = 4; i < argc; i++) {
		if (argv[i][0] != '-')
			continue;
		switch (argv[i][1]) {
		case 'a':
			if (argc < i + 2) {
				show_usage(argc, argv);
				return -1;
			}
			a = atoi(argv[++i]);
			cpu_affinities[next_aff++] = a;
			use_affinity = 1;
			printf_verbose("Adding CPU %d affinity\n", a);
			break;
		case 'c':
			if (argc < i + 2) {
				show_usage(argc, argv);
				return -1;
			}
			rduration = atol(argv[++i]);
			break;
		case 'd':
			if (argc < i + 2) {
				show_usage(argc, argv);
				return -1;
			}
			wdelay = atol(argv[++i]);
			break;
		case 'e':
			if (argc < i + 2) {
				show_usage(argc, argv);
				return -1;
			}
			wduration = atol(argv[++i]);
			break;
		case 'v':
			verbose_mode = 1;
			break;
		}
	}

	printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
		duration, nr_readers, nr_writers);
	printf_verbose("Writer delay : %lu loops.\n", wdelay);
	printf_verbose("Writer duration : %lu loops.\n", wduration);
	printf_verbose("Reader duration : %lu loops.\n", rduration);
	printf_verbose("thread %-6s, tid %lu\n",
			"main", urcu_get_thread_id());

	err = pthread_rwlock_init(&lock, NULL);
	if (err != 0) {
		fprintf(stderr, "pthread_rwlock_init: (%d) %s\n", err, strerror(err));
		exit(1);
	}

	tid_reader = calloc(nr_readers, sizeof(*tid_reader));
	tid_writer = calloc(nr_writers, sizeof(*tid_writer));
	count_reader = calloc(nr_readers, sizeof(*count_reader));
	count_writer = calloc(nr_writers, sizeof(*count_writer));

	next_aff = 0;

	for (i = 0; i < nr_readers; i++) {
		err = pthread_create(&tid_reader[i], NULL, thr_reader,
				     &count_reader[i]);
		if (err != 0)
			exit(1);
	}
	for (i = 0; i < nr_writers; i++) {
		err = pthread_create(&tid_writer[i], NULL, thr_writer,
				     &count_writer[i]);
		if (err != 0)
			exit(1);
	}

	cmm_smp_mb();

	test_go = 1;

	sleep(duration);

	test_stop = 1;

	for (i = 0; i < nr_readers; i++) {
		err = pthread_join(tid_reader[i], &tret);
		if (err != 0)
			exit(1);
		tot_reads += count_reader[i];
	}
	for (i = 0; i < nr_writers; i++) {
		err = pthread_join(tid_writer[i], &tret);
		if (err != 0)
			exit(1);
		tot_writes += count_writer[i];
	}

	printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
	       tot_writes);
	printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
		"nr_writers %3u "
		"wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
		argv[0], duration, nr_readers, rduration, wduration,
		nr_writers, wdelay, tot_reads, tot_writes,
		tot_reads + tot_writes);

	err = pthread_rwlock_destroy(&lock);
	if (err != 0) {
		fprintf(stderr, "pthread_rwlock_destroy: (%d) %s\n", err, strerror(err));
		exit(1);
	}
	free(tid_reader);
	free(tid_writer);
	free(count_reader);
	free(count_writer);
	return 0;
}
Commit	Line	Data
	1	/*
	2	* test_urcu.c
	3	*
	4	* Userspace RCU library - test program
	5	*
	6	* Copyright February 2009 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License along
	19	* with this program; if not, write to the Free Software Foundation, Inc.,
	20	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	21	*/
	22
	23	#include <stdio.h>
	24	#include <pthread.h>
	25	#include <stdlib.h>
	26	#include <string.h>
	27	#include <sys/types.h>
	28	#include <sys/wait.h>
	29	#include <unistd.h>
	30	#include <stdio.h>
	31	#include <assert.h>
	32	#include <errno.h>
	33
	34	#include <urcu/arch.h>
	35	#include <urcu/tls-compat.h>
	36	#include "cpuset.h"
	37	#include "thread-id.h"
	38
	39	/* hardcoded number of CPUs */
	40	#define NR_CPUS 16384
	41
	42	#ifndef DYNAMIC_LINK_TEST
	43	#define _LGPL_SOURCE
	44	#endif
	45	#include <urcu.h>
	46
	47	struct test_array {
	48	int a;
	49	};
	50
	51	/*
	52	* static rwlock initializer is broken on Cygwin. Use runtime
	53	* initialization.
	54	*/
	55	pthread_rwlock_t lock;
	56
	57	static volatile int test_go, test_stop;
	58
	59	static unsigned long wdelay;
	60
	61	static volatile struct test_array test_array = { 8 };
	62
	63	static unsigned long duration;
	64
	65	/* read-side C.S. duration, in loops */
	66	static unsigned long rduration;
	67
	68	/* write-side C.S. duration, in loops */
	69	static unsigned long wduration;
	70
	71	static inline void loop_sleep(unsigned long loops)
	72	{
	73	while (loops-- != 0)
	74	caa_cpu_relax();
	75	}
	76
	77	static int verbose_mode;
	78
	79	#define printf_verbose(fmt, args...) \
	80	do { \
	81	if (verbose_mode) \
	82	printf(fmt, args); \
	83	} while (0)
	84
	85	static unsigned int cpu_affinities[NR_CPUS];
	86	static unsigned int next_aff = 0;
	87	static int use_affinity = 0;
	88
	89	pthread_mutex_t affinity_mutex = PTHREAD_MUTEX_INITIALIZER;
	90
	91	static void set_affinity(void)
	92	{
	93	#if HAVE_SCHED_SETAFFINITY
	94	cpu_set_t mask;
	95	int cpu, ret;
	96	#endif /* HAVE_SCHED_SETAFFINITY */
	97
	98	if (!use_affinity)
	99	return;
	100
	101	#if HAVE_SCHED_SETAFFINITY
	102	ret = pthread_mutex_lock(&affinity_mutex);
	103	if (ret) {
	104	perror("Error in pthread mutex lock");
	105	exit(-1);
	106	}
	107	cpu = cpu_affinities[next_aff++];
	108	ret = pthread_mutex_unlock(&affinity_mutex);
	109	if (ret) {
	110	perror("Error in pthread mutex unlock");
	111	exit(-1);
	112	}
	113
	114	CPU_ZERO(&mask);
	115	CPU_SET(cpu, &mask);
	116	#if SCHED_SETAFFINITY_ARGS == 2
	117	sched_setaffinity(0, &mask);
	118	#else
	119	sched_setaffinity(0, sizeof(mask), &mask);
	120	#endif
	121	#endif /* HAVE_SCHED_SETAFFINITY */
	122	}
	123
	124	/*
	125	* returns 0 if test should end.
	126	*/
	127	static int test_duration_write(void)
	128	{
	129	return !test_stop;
	130	}
	131
	132	static int test_duration_read(void)
	133	{
	134	return !test_stop;
	135	}
	136
	137	static DEFINE_URCU_TLS(unsigned long long, nr_writes);
	138	static DEFINE_URCU_TLS(unsigned long long, nr_reads);
	139
	140	static unsigned int nr_readers;
	141	static unsigned int nr_writers;
	142
	143	pthread_mutex_t rcu_copy_mutex = PTHREAD_MUTEX_INITIALIZER;
	144
	145	void rcu_copy_mutex_lock(void)
	146	{
	147	int ret;
	148	ret = pthread_mutex_lock(&rcu_copy_mutex);
	149	if (ret) {
	150	perror("Error in pthread mutex lock");
	151	exit(-1);
	152	}
	153	}
	154
	155	void rcu_copy_mutex_unlock(void)
	156	{
	157	int ret;
	158
	159	ret = pthread_mutex_unlock(&rcu_copy_mutex);
	160	if (ret) {
	161	perror("Error in pthread mutex unlock");
	162	exit(-1);
	163	}
	164	}
	165
	166	void thr_reader(void _count)
	167	{
	168	unsigned long long *count = _count;
	169
	170	printf_verbose("thread_begin %s, tid %lu\n",
	171	"reader", urcu_get_thread_id());
	172
	173	set_affinity();
	174
	175	while (!test_go)
	176	{
	177	}
	178
	179	for (;;) {
	180	int a, ret;
	181
	182	ret = pthread_rwlock_rdlock(&lock);
	183	if (ret) {
	184	fprintf(stderr, "reader pthread_rwlock_rdlock: %s\n", strerror(ret));
	185	abort();
	186	}
	187
	188	a = test_array.a;
	189	assert(a == 8);
	190	if (caa_unlikely(rduration))
	191	loop_sleep(rduration);
	192
	193	ret = pthread_rwlock_unlock(&lock);
	194	if (ret) {
	195	fprintf(stderr, "reader pthread_rwlock_unlock: %s\n", strerror(ret));
	196	abort();
	197	}
	198
	199	URCU_TLS(nr_reads)++;
	200	if (caa_unlikely(!test_duration_read()))
	201	break;
	202	}
	203
	204	*count = URCU_TLS(nr_reads);
	205
	206	printf_verbose("thread_end %s, tid %lu, count %llu\n",
	207	"reader", urcu_get_thread_id(), *count);
	208	return ((void*)1);
	209
	210	}
	211
	212	void thr_writer(void _count)
	213	{
	214	unsigned long long *count = _count;
	215
	216	printf_verbose("thread_begin %s, tid %lu\n",
	217	"writer", urcu_get_thread_id());
	218
	219	set_affinity();
	220
	221	while (!test_go)
	222	{
	223	}
	224	cmm_smp_mb();
	225
	226	for (;;) {
	227	int ret;
	228
	229	ret = pthread_rwlock_wrlock(&lock);
	230	if (ret) {
	231	fprintf(stderr, "writer pthread_rwlock_wrlock: %s\n", strerror(ret));
	232	abort();
	233	}
	234
	235	test_array.a = 0;
	236	test_array.a = 8;
	237	if (caa_unlikely(wduration))
	238	loop_sleep(wduration);
	239
	240	ret = pthread_rwlock_unlock(&lock);
	241	if (ret) {
	242	fprintf(stderr, "writer pthread_rwlock_unlock: %s\n", strerror(ret));
	243	abort();
	244	}
	245
	246	URCU_TLS(nr_writes)++;
	247	if (caa_unlikely(!test_duration_write()))
	248	break;
	249	if (caa_unlikely(wdelay))
	250	loop_sleep(wdelay);
	251	}
	252	*count = URCU_TLS(nr_writes);
	253
	254	printf_verbose("thread_end %s, tid %lu, count %llu\n",
	255	"writer", urcu_get_thread_id(), *count);
	256	return ((void*)2);
	257	}
	258
	259	void show_usage(int argc, char **argv)
	260	{
	261	printf("Usage : %s nr_readers nr_writers duration (s) <OPTIONS>\n",
	262	argv[0]);
	263	printf("OPTIONS:\n");
	264	printf(" [-d delay] (writer period (us))\n");
	265	printf(" [-c duration] (reader C.S. duration (in loops))\n");
	266	printf(" [-e duration] (writer C.S. duration (in loops))\n");
	267	printf(" [-v] (verbose output)\n");
	268	printf(" [-a cpu#] [-a cpu#]... (affinity)\n");
	269	printf("\n");
	270	}
	271
	272	int main(int argc, char **argv)
	273	{
	274	int err;
	275	pthread_t tid_reader, tid_writer;
	276	void *tret;
	277	unsigned long long count_reader, count_writer;
	278	unsigned long long tot_reads = 0, tot_writes = 0;
	279	int i, a;
	280
	281	if (argc < 4) {
	282	show_usage(argc, argv);
	283	return -1;
	284	}
	285	cmm_smp_mb();
	286
	287	err = sscanf(argv[1], "%u", &nr_readers);
	288	if (err != 1) {
	289	show_usage(argc, argv);
	290	return -1;
	291	}
	292
	293	err = sscanf(argv[2], "%u", &nr_writers);
	294	if (err != 1) {
	295	show_usage(argc, argv);
	296	return -1;
	297	}
	298
	299	err = sscanf(argv[3], "%lu", &duration);
	300	if (err != 1) {
	301	show_usage(argc, argv);
	302	return -1;
	303	}
	304
	305	for (i = 4; i < argc; i++) {
	306	if (argv[i][0] != '-')
	307	continue;
	308	switch (argv[i][1]) {
	309	case 'a':
	310	if (argc < i + 2) {
	311	show_usage(argc, argv);
	312	return -1;
	313	}
	314	a = atoi(argv[++i]);
	315	cpu_affinities[next_aff++] = a;
	316	use_affinity = 1;
	317	printf_verbose("Adding CPU %d affinity\n", a);
	318	break;
	319	case 'c':
	320	if (argc < i + 2) {
	321	show_usage(argc, argv);
	322	return -1;
	323	}
	324	rduration = atol(argv[++i]);
	325	break;
	326	case 'd':
	327	if (argc < i + 2) {
	328	show_usage(argc, argv);
	329	return -1;
	330	}
	331	wdelay = atol(argv[++i]);
	332	break;
	333	case 'e':
	334	if (argc < i + 2) {
	335	show_usage(argc, argv);
	336	return -1;
	337	}
	338	wduration = atol(argv[++i]);
	339	break;
	340	case 'v':
	341	verbose_mode = 1;
	342	break;
	343	}
	344	}
	345
	346	printf_verbose("running test for %lu seconds, %u readers, %u writers.\n",
	347	duration, nr_readers, nr_writers);
	348	printf_verbose("Writer delay : %lu loops.\n", wdelay);
	349	printf_verbose("Writer duration : %lu loops.\n", wduration);
	350	printf_verbose("Reader duration : %lu loops.\n", rduration);
	351	printf_verbose("thread %-6s, tid %lu\n",
	352	"main", urcu_get_thread_id());
	353
	354	err = pthread_rwlock_init(&lock, NULL);
	355	if (err != 0) {
	356	fprintf(stderr, "pthread_rwlock_init: (%d) %s\n", err, strerror(err));
	357	exit(1);
	358	}
	359
	360	tid_reader = calloc(nr_readers, sizeof(*tid_reader));
	361	tid_writer = calloc(nr_writers, sizeof(*tid_writer));
	362	count_reader = calloc(nr_readers, sizeof(*count_reader));
	363	count_writer = calloc(nr_writers, sizeof(*count_writer));
	364
	365	next_aff = 0;
	366
	367	for (i = 0; i < nr_readers; i++) {
	368	err = pthread_create(&tid_reader[i], NULL, thr_reader,
	369	&count_reader[i]);
	370	if (err != 0)
	371	exit(1);
	372	}
	373	for (i = 0; i < nr_writers; i++) {
	374	err = pthread_create(&tid_writer[i], NULL, thr_writer,
	375	&count_writer[i]);
	376	if (err != 0)
	377	exit(1);
	378	}
	379
	380	cmm_smp_mb();
	381
	382	test_go = 1;
	383
	384	sleep(duration);
	385
	386	test_stop = 1;
	387
	388	for (i = 0; i < nr_readers; i++) {
	389	err = pthread_join(tid_reader[i], &tret);
	390	if (err != 0)
	391	exit(1);
	392	tot_reads += count_reader[i];
	393	}
	394	for (i = 0; i < nr_writers; i++) {
	395	err = pthread_join(tid_writer[i], &tret);
	396	if (err != 0)
	397	exit(1);
	398	tot_writes += count_writer[i];
	399	}
	400
	401	printf_verbose("total number of reads : %llu, writes %llu\n", tot_reads,
	402	tot_writes);
	403	printf("SUMMARY %-25s testdur %4lu nr_readers %3u rdur %6lu wdur %6lu "
	404	"nr_writers %3u "
	405	"wdelay %6lu nr_reads %12llu nr_writes %12llu nr_ops %12llu\n",
	406	argv[0], duration, nr_readers, rduration, wduration,
	407	nr_writers, wdelay, tot_reads, tot_writes,
	408	tot_reads + tot_writes);
	409
	410	err = pthread_rwlock_destroy(&lock);
	411	if (err != 0) {
	412	fprintf(stderr, "pthread_rwlock_destroy: (%d) %s\n", err, strerror(err));
	413	exit(1);
	414	}
	415	free(tid_reader);
	416	free(tid_writer);
	417	free(count_reader);
	418	free(count_writer);
	419	return 0;
	420	}