1 /*
2  * This application is Copyright 2012 Red Hat, Inc.
3  *	Doug Ledford <dledford@redhat.com>
4  *
5  * mq_perf_tests 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, version 3.
8  *
9  * mq_perf_tests is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * For the full text of the license, see <http://www.gnu.org/licenses/>.
15  *
16  * mq_perf_tests.c
17  *   Tests various types of message queue workloads, concentrating on those
18  *   situations that invole large message sizes, large message queue depths,
19  *   or both, and reports back useful metrics about kernel message queue
20  *   performance.
21  *
22  */
23 #define _GNU_SOURCE
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <unistd.h>
27 #include <fcntl.h>
28 #include <string.h>
29 #include <limits.h>
30 #include <errno.h>
31 #include <signal.h>
32 #include <pthread.h>
33 #include <sched.h>
34 #include <sys/types.h>
35 #include <sys/time.h>
36 #include <sys/resource.h>
37 #include <sys/stat.h>
38 #include <sys/param.h>
39 #include <mqueue.h>
40 #include <popt.h>
41 #include <error.h>
42 
43 #include "../kselftest.h"
44 
45 static char *usage =
46 "Usage:\n"
47 "  %s [-c #[,#..] -f] path\n"
48 "\n"
49 "	-c #	Skip most tests and go straight to a high queue depth test\n"
50 "		and then run that test continuously (useful for running at\n"
51 "		the same time as some other workload to see how much the\n"
52 "		cache thrashing caused by adding messages to a very deep\n"
53 "		queue impacts the performance of other programs).  The number\n"
54 "		indicates which CPU core we should bind the process to during\n"
55 "		the run.  If you have more than one physical CPU, then you\n"
56 "		will need one copy per physical CPU package, and you should\n"
57 "		specify the CPU cores to pin ourself to via a comma separated\n"
58 "		list of CPU values.\n"
59 "	-f	Only usable with continuous mode.  Pin ourself to the CPUs\n"
60 "		as requested, then instead of looping doing a high mq\n"
61 "		workload, just busy loop.  This will allow us to lock up a\n"
62 "		single CPU just like we normally would, but without actually\n"
63 "		thrashing the CPU cache.  This is to make it easier to get\n"
64 "		comparable numbers from some other workload running on the\n"
65 "		other CPUs.  One set of numbers with # CPUs locked up running\n"
66 "		an mq workload, and another set of numbers with those same\n"
67 "		CPUs locked away from the test workload, but not doing\n"
68 "		anything to trash the cache like the mq workload might.\n"
69 "	path	Path name of the message queue to create\n"
70 "\n"
71 "	Note: this program must be run as root in order to enable all tests\n"
72 "\n";
73 
74 char *MAX_MSGS = "/proc/sys/fs/mqueue/msg_max";
75 char *MAX_MSGSIZE = "/proc/sys/fs/mqueue/msgsize_max";
76 
77 #define MAX_CPUS 64
78 char *cpu_option_string;
79 int cpus_to_pin[MAX_CPUS];
80 int num_cpus_to_pin;
81 pthread_t cpu_threads[MAX_CPUS];
82 pthread_t main_thread;
83 cpu_set_t *cpu_set;
84 int cpu_set_size;
85 int cpus_online;
86 
87 #define MSG_SIZE 16
88 #define TEST1_LOOPS 10000000
89 #define TEST2_LOOPS 100000
90 int continuous_mode;
91 int continuous_mode_fake;
92 
93 struct rlimit saved_limits, cur_limits;
94 int saved_max_msgs, saved_max_msgsize;
95 int cur_max_msgs, cur_max_msgsize;
96 FILE *max_msgs, *max_msgsize;
97 int cur_nice;
98 char *queue_path = "/mq_perf_tests";
99 mqd_t queue = -1;
100 struct mq_attr result;
101 int mq_prio_max;
102 
103 const struct poptOption options[] = {
104 	{
105 		.longName = "continuous",
106 		.shortName = 'c',
107 		.argInfo = POPT_ARG_STRING,
108 		.arg = &cpu_option_string,
109 		.val = 'c',
110 		.descrip = "Run continuous tests at a high queue depth in "
111 			"order to test the effects of cache thrashing on "
112 			"other tasks on the system.  This test is intended "
113 			"to be run on one core of each physical CPU while "
114 			"some other CPU intensive task is run on all the other "
115 			"cores of that same physical CPU and the other task "
116 			"is timed.  It is assumed that the process of adding "
117 			"messages to the message queue in a tight loop will "
118 			"impact that other task to some degree.  Once the "
119 			"tests are performed in this way, you should then "
120 			"re-run the tests using fake mode in order to check "
121 			"the difference in time required to perform the CPU "
122 			"intensive task",
123 		.argDescrip = "cpu[,cpu]",
124 	},
125 	{
126 		.longName = "fake",
127 		.shortName = 'f',
128 		.argInfo = POPT_ARG_NONE,
129 		.arg = &continuous_mode_fake,
130 		.val = 0,
131 		.descrip = "Tie up the CPUs that we would normally tie up in"
132 			"continuous mode, but don't actually do any mq stuff, "
133 			"just keep the CPU busy so it can't be used to process "
134 			"system level tasks as this would free up resources on "
135 			"the other CPU cores and skew the comparison between "
136 			"the no-mqueue work and mqueue work tests",
137 		.argDescrip = NULL,
138 	},
139 	{
140 		.longName = "path",
141 		.shortName = 'p',
142 		.argInfo = POPT_ARG_STRING | POPT_ARGFLAG_SHOW_DEFAULT,
143 		.arg = &queue_path,
144 		.val = 'p',
145 		.descrip = "The name of the path to use in the mqueue "
146 			"filesystem for our tests",
147 		.argDescrip = "pathname",
148 	},
149 	POPT_AUTOHELP
150 	POPT_TABLEEND
151 };
152 
153 static inline void __set(FILE *stream, int value, char *err_msg);
154 void shutdown(int exit_val, char *err_cause, int line_no);
155 void sig_action_SIGUSR1(int signum, siginfo_t *info, void *context);
156 void sig_action(int signum, siginfo_t *info, void *context);
157 static inline int get(FILE *stream);
158 static inline void set(FILE *stream, int value);
159 static inline int try_set(FILE *stream, int value);
160 static inline void getr(int type, struct rlimit *rlim);
161 static inline void setr(int type, struct rlimit *rlim);
162 static inline void open_queue(struct mq_attr *attr);
163 void increase_limits(void);
164 
165 static inline void __set(FILE *stream, int value, char *err_msg)
166 {
167 	rewind(stream);
168 	if (fprintf(stream, "%d", value) < 0)
169 		perror(err_msg);
170 }
171 
172 
173 void shutdown(int exit_val, char *err_cause, int line_no)
174 {
175 	static int in_shutdown = 0;
176 	int errno_at_shutdown = errno;
177 	int i;
178 
179 	/* In case we get called by multiple threads or from an sighandler */
180 	if (in_shutdown++)
181 		return;
182 
183 	/* Free the cpu_set allocated using CPU_ALLOC in main function */
184 	CPU_FREE(cpu_set);
185 
186 	for (i = 0; i < num_cpus_to_pin; i++)
187 		if (cpu_threads[i]) {
188 			pthread_kill(cpu_threads[i], SIGUSR1);
189 			pthread_join(cpu_threads[i], NULL);
190 		}
191 
192 	if (queue != -1)
193 		if (mq_close(queue))
194 			perror("mq_close() during shutdown");
195 	if (queue_path)
196 		/*
197 		 * Be silent if this fails, if we cleaned up already it's
198 		 * expected to fail
199 		 */
200 		mq_unlink(queue_path);
201 	if (saved_max_msgs)
202 		__set(max_msgs, saved_max_msgs,
203 		      "failed to restore saved_max_msgs");
204 	if (saved_max_msgsize)
205 		__set(max_msgsize, saved_max_msgsize,
206 		      "failed to restore saved_max_msgsize");
207 	if (exit_val)
208 		error(exit_val, errno_at_shutdown, "%s at %d",
209 		      err_cause, line_no);
210 	exit(0);
211 }
212 
213 void sig_action_SIGUSR1(int signum, siginfo_t *info, void *context)
214 {
215 	if (pthread_self() != main_thread)
216 		pthread_exit(0);
217 	else {
218 		fprintf(stderr, "Caught signal %d in SIGUSR1 handler, "
219 				"exiting\n", signum);
220 		shutdown(0, "", 0);
221 		fprintf(stderr, "\n\nReturned from shutdown?!?!\n\n");
222 		exit(0);
223 	}
224 }
225 
226 void sig_action(int signum, siginfo_t *info, void *context)
227 {
228 	if (pthread_self() != main_thread)
229 		pthread_kill(main_thread, signum);
230 	else {
231 		fprintf(stderr, "Caught signal %d, exiting\n", signum);
232 		shutdown(0, "", 0);
233 		fprintf(stderr, "\n\nReturned from shutdown?!?!\n\n");
234 		exit(0);
235 	}
236 }
237 
238 static inline int get(FILE *stream)
239 {
240 	int value;
241 	rewind(stream);
242 	if (fscanf(stream, "%d", &value) != 1)
243 		shutdown(4, "Error reading /proc entry", __LINE__);
244 	return value;
245 }
246 
247 static inline void set(FILE *stream, int value)
248 {
249 	int new_value;
250 
251 	rewind(stream);
252 	if (fprintf(stream, "%d", value) < 0)
253 		return shutdown(5, "Failed writing to /proc file", __LINE__);
254 	new_value = get(stream);
255 	if (new_value != value)
256 		return shutdown(5, "We didn't get what we wrote to /proc back",
257 				__LINE__);
258 }
259 
260 static inline int try_set(FILE *stream, int value)
261 {
262 	int new_value;
263 
264 	rewind(stream);
265 	fprintf(stream, "%d", value);
266 	new_value = get(stream);
267 	return new_value == value;
268 }
269 
270 static inline void getr(int type, struct rlimit *rlim)
271 {
272 	if (getrlimit(type, rlim))
273 		shutdown(6, "getrlimit()", __LINE__);
274 }
275 
276 static inline void setr(int type, struct rlimit *rlim)
277 {
278 	if (setrlimit(type, rlim))
279 		shutdown(7, "setrlimit()", __LINE__);
280 }
281 
282 /**
283  * open_queue - open the global queue for testing
284  * @attr - An attr struct specifying the desired queue traits
285  * @result - An attr struct that lists the actual traits the queue has
286  *
287  * This open is not allowed to fail, failure will result in an orderly
288  * shutdown of the program.  The global queue_path is used to set what
289  * queue to open, the queue descriptor is saved in the global queue
290  * variable.
291  */
292 static inline void open_queue(struct mq_attr *attr)
293 {
294 	int flags = O_RDWR | O_EXCL | O_CREAT | O_NONBLOCK;
295 	int perms = DEFFILEMODE;
296 
297 	queue = mq_open(queue_path, flags, perms, attr);
298 	if (queue == -1)
299 		shutdown(1, "mq_open()", __LINE__);
300 	if (mq_getattr(queue, &result))
301 		shutdown(1, "mq_getattr()", __LINE__);
302 	printf("\n\tQueue %s created:\n", queue_path);
303 	printf("\t\tmq_flags:\t\t\t%s\n", result.mq_flags & O_NONBLOCK ?
304 	       "O_NONBLOCK" : "(null)");
305 	printf("\t\tmq_maxmsg:\t\t\t%lu\n", result.mq_maxmsg);
306 	printf("\t\tmq_msgsize:\t\t\t%lu\n", result.mq_msgsize);
307 	printf("\t\tmq_curmsgs:\t\t\t%lu\n", result.mq_curmsgs);
308 }
309 
310 void *fake_cont_thread(void *arg)
311 {
312 	int i;
313 
314 	for (i = 0; i < num_cpus_to_pin; i++)
315 		if (cpu_threads[i] == pthread_self())
316 			break;
317 	printf("\tStarted fake continuous mode thread %d on CPU %d\n", i,
318 	       cpus_to_pin[i]);
319 	while (1)
320 		;
321 }
322 
323 void *cont_thread(void *arg)
324 {
325 	char buff[MSG_SIZE];
326 	int i, priority;
327 
328 	for (i = 0; i < num_cpus_to_pin; i++)
329 		if (cpu_threads[i] == pthread_self())
330 			break;
331 	printf("\tStarted continuous mode thread %d on CPU %d\n", i,
332 	       cpus_to_pin[i]);
333 	while (1) {
334 		while (mq_send(queue, buff, sizeof(buff), 0) == 0)
335 			;
336 		mq_receive(queue, buff, sizeof(buff), &priority);
337 	}
338 }
339 
340 #define drain_queue() \
341 	while (mq_receive(queue, buff, MSG_SIZE, &prio_in) == MSG_SIZE)
342 
343 #define do_untimed_send() \
344 	do { \
345 		if (mq_send(queue, buff, MSG_SIZE, prio_out)) \
346 			shutdown(3, "Test send failure", __LINE__); \
347 	} while (0)
348 
349 #define do_send_recv() \
350 	do { \
351 		clock_gettime(clock, &start); \
352 		if (mq_send(queue, buff, MSG_SIZE, prio_out)) \
353 			shutdown(3, "Test send failure", __LINE__); \
354 		clock_gettime(clock, &middle); \
355 		if (mq_receive(queue, buff, MSG_SIZE, &prio_in) != MSG_SIZE) \
356 			shutdown(3, "Test receive failure", __LINE__); \
357 		clock_gettime(clock, &end); \
358 		nsec = ((middle.tv_sec - start.tv_sec) * 1000000000) + \
359 			(middle.tv_nsec - start.tv_nsec); \
360 		send_total.tv_nsec += nsec; \
361 		if (send_total.tv_nsec >= 1000000000) { \
362 			send_total.tv_sec++; \
363 			send_total.tv_nsec -= 1000000000; \
364 		} \
365 		nsec = ((end.tv_sec - middle.tv_sec) * 1000000000) + \
366 			(end.tv_nsec - middle.tv_nsec); \
367 		recv_total.tv_nsec += nsec; \
368 		if (recv_total.tv_nsec >= 1000000000) { \
369 			recv_total.tv_sec++; \
370 			recv_total.tv_nsec -= 1000000000; \
371 		} \
372 	} while (0)
373 
374 struct test {
375 	char *desc;
376 	void (*func)(int *);
377 };
378 
379 void const_prio(int *prio)
380 {
381 	return;
382 }
383 
384 void inc_prio(int *prio)
385 {
386 	if (++*prio == mq_prio_max)
387 		*prio = 0;
388 }
389 
390 void dec_prio(int *prio)
391 {
392 	if (--*prio < 0)
393 		*prio = mq_prio_max - 1;
394 }
395 
396 void random_prio(int *prio)
397 {
398 	*prio = random() % mq_prio_max;
399 }
400 
401 struct test test2[] = {
402 	{"\n\tTest #2a: Time send/recv message, queue full, constant prio\n",
403 		const_prio},
404 	{"\n\tTest #2b: Time send/recv message, queue full, increasing prio\n",
405 		inc_prio},
406 	{"\n\tTest #2c: Time send/recv message, queue full, decreasing prio\n",
407 		dec_prio},
408 	{"\n\tTest #2d: Time send/recv message, queue full, random prio\n",
409 		random_prio},
410 	{NULL, NULL}
411 };
412 
413 /**
414  * Tests to perform (all done with MSG_SIZE messages):
415  *
416  * 1) Time to add/remove message with 0 messages on queue
417  * 1a) with constant prio
418  * 2) Time to add/remove message when queue close to capacity:
419  * 2a) with constant prio
420  * 2b) with increasing prio
421  * 2c) with decreasing prio
422  * 2d) with random prio
423  * 3) Test limits of priorities honored (double check _SC_MQ_PRIO_MAX)
424  */
425 void *perf_test_thread(void *arg)
426 {
427 	char buff[MSG_SIZE];
428 	int prio_out, prio_in;
429 	int i;
430 	clockid_t clock;
431 	pthread_t *t;
432 	struct timespec res, start, middle, end, send_total, recv_total;
433 	unsigned long long nsec;
434 	struct test *cur_test;
435 
436 	t = &cpu_threads[0];
437 	printf("\n\tStarted mqueue performance test thread on CPU %d\n",
438 	       cpus_to_pin[0]);
439 	mq_prio_max = sysconf(_SC_MQ_PRIO_MAX);
440 	if (mq_prio_max == -1)
441 		shutdown(2, "sysconf(_SC_MQ_PRIO_MAX)", __LINE__);
442 	if (pthread_getcpuclockid(cpu_threads[0], &clock) != 0)
443 		shutdown(2, "pthread_getcpuclockid", __LINE__);
444 
445 	if (clock_getres(clock, &res))
446 		shutdown(2, "clock_getres()", __LINE__);
447 
448 	printf("\t\tMax priorities:\t\t\t%d\n", mq_prio_max);
449 	printf("\t\tClock resolution:\t\t%lu nsec%s\n", res.tv_nsec,
450 	       res.tv_nsec > 1 ? "s" : "");
451 
452 
453 
454 	printf("\n\tTest #1: Time send/recv message, queue empty\n");
455 	printf("\t\t(%d iterations)\n", TEST1_LOOPS);
456 	prio_out = 0;
457 	send_total.tv_sec = 0;
458 	send_total.tv_nsec = 0;
459 	recv_total.tv_sec = 0;
460 	recv_total.tv_nsec = 0;
461 	for (i = 0; i < TEST1_LOOPS; i++)
462 		do_send_recv();
463 	printf("\t\tSend msg:\t\t\t%ld.%lus total time\n",
464 	       send_total.tv_sec, send_total.tv_nsec);
465 	nsec = ((unsigned long long)send_total.tv_sec * 1000000000 +
466 		 send_total.tv_nsec) / TEST1_LOOPS;
467 	printf("\t\t\t\t\t\t%lld nsec/msg\n", nsec);
468 	printf("\t\tRecv msg:\t\t\t%ld.%lus total time\n",
469 	       recv_total.tv_sec, recv_total.tv_nsec);
470 	nsec = ((unsigned long long)recv_total.tv_sec * 1000000000 +
471 		recv_total.tv_nsec) / TEST1_LOOPS;
472 	printf("\t\t\t\t\t\t%lld nsec/msg\n", nsec);
473 
474 
475 	for (cur_test = test2; cur_test->desc != NULL; cur_test++) {
476 		printf("%s:\n", cur_test->desc);
477 		printf("\t\t(%d iterations)\n", TEST2_LOOPS);
478 		prio_out = 0;
479 		send_total.tv_sec = 0;
480 		send_total.tv_nsec = 0;
481 		recv_total.tv_sec = 0;
482 		recv_total.tv_nsec = 0;
483 		printf("\t\tFilling queue...");
484 		fflush(stdout);
485 		clock_gettime(clock, &start);
486 		for (i = 0; i < result.mq_maxmsg - 1; i++) {
487 			do_untimed_send();
488 			cur_test->func(&prio_out);
489 		}
490 		clock_gettime(clock, &end);
491 		nsec = ((unsigned long long)(end.tv_sec - start.tv_sec) *
492 			1000000000) + (end.tv_nsec - start.tv_nsec);
493 		printf("done.\t\t%lld.%llds\n", nsec / 1000000000,
494 		       nsec % 1000000000);
495 		printf("\t\tTesting...");
496 		fflush(stdout);
497 		for (i = 0; i < TEST2_LOOPS; i++) {
498 			do_send_recv();
499 			cur_test->func(&prio_out);
500 		}
501 		printf("done.\n");
502 		printf("\t\tSend msg:\t\t\t%ld.%lus total time\n",
503 		       send_total.tv_sec, send_total.tv_nsec);
504 		nsec = ((unsigned long long)send_total.tv_sec * 1000000000 +
505 			 send_total.tv_nsec) / TEST2_LOOPS;
506 		printf("\t\t\t\t\t\t%lld nsec/msg\n", nsec);
507 		printf("\t\tRecv msg:\t\t\t%ld.%lus total time\n",
508 		       recv_total.tv_sec, recv_total.tv_nsec);
509 		nsec = ((unsigned long long)recv_total.tv_sec * 1000000000 +
510 			recv_total.tv_nsec) / TEST2_LOOPS;
511 		printf("\t\t\t\t\t\t%lld nsec/msg\n", nsec);
512 		printf("\t\tDraining queue...");
513 		fflush(stdout);
514 		clock_gettime(clock, &start);
515 		drain_queue();
516 		clock_gettime(clock, &end);
517 		nsec = ((unsigned long long)(end.tv_sec - start.tv_sec) *
518 			1000000000) + (end.tv_nsec - start.tv_nsec);
519 		printf("done.\t\t%lld.%llds\n", nsec / 1000000000,
520 		       nsec % 1000000000);
521 	}
522 	return 0;
523 }
524 
525 void increase_limits(void)
526 {
527 	cur_limits.rlim_cur = RLIM_INFINITY;
528 	cur_limits.rlim_max = RLIM_INFINITY;
529 	setr(RLIMIT_MSGQUEUE, &cur_limits);
530 	while (try_set(max_msgs, cur_max_msgs += 10))
531 		;
532 	cur_max_msgs = get(max_msgs);
533 	while (try_set(max_msgsize, cur_max_msgsize += 1024))
534 		;
535 	cur_max_msgsize = get(max_msgsize);
536 	if (setpriority(PRIO_PROCESS, 0, -20) != 0)
537 		shutdown(2, "setpriority()", __LINE__);
538 	cur_nice = -20;
539 }
540 
541 int main(int argc, char *argv[])
542 {
543 	struct mq_attr attr;
544 	char *option, *next_option;
545 	int i, cpu, rc;
546 	struct sigaction sa;
547 	poptContext popt_context;
548 	void *retval;
549 
550 	main_thread = pthread_self();
551 	num_cpus_to_pin = 0;
552 
553 	if (sysconf(_SC_NPROCESSORS_ONLN) == -1) {
554 		perror("sysconf(_SC_NPROCESSORS_ONLN)");
555 		exit(1);
556 	}
557 
558 	if (getuid() != 0)
559 		ksft_exit_skip("Not running as root, but almost all tests "
560 			"require root in order to modify\nsystem settings.  "
561 			"Exiting.\n");
562 
563 	cpus_online = MIN(MAX_CPUS, sysconf(_SC_NPROCESSORS_ONLN));
564 	cpu_set = CPU_ALLOC(cpus_online);
565 	if (cpu_set == NULL) {
566 		perror("CPU_ALLOC()");
567 		exit(1);
568 	}
569 	cpu_set_size = CPU_ALLOC_SIZE(cpus_online);
570 	CPU_ZERO_S(cpu_set_size, cpu_set);
571 
572 	popt_context = poptGetContext(NULL, argc, (const char **)argv,
573 				      options, 0);
574 
575 	while ((rc = poptGetNextOpt(popt_context)) > 0) {
576 		switch (rc) {
577 		case 'c':
578 			continuous_mode = 1;
579 			option = cpu_option_string;
580 			do {
581 				next_option = strchr(option, ',');
582 				if (next_option)
583 					*next_option = '\0';
584 				cpu = atoi(option);
585 				if (cpu >= cpus_online)
586 					fprintf(stderr, "CPU %d exceeds "
587 						"cpus online, ignoring.\n",
588 						cpu);
589 				else
590 					cpus_to_pin[num_cpus_to_pin++] = cpu;
591 				if (next_option)
592 					option = ++next_option;
593 			} while (next_option && num_cpus_to_pin < MAX_CPUS);
594 			/* Double check that they didn't give us the same CPU
595 			 * more than once */
596 			for (cpu = 0; cpu < num_cpus_to_pin; cpu++) {
597 				if (CPU_ISSET_S(cpus_to_pin[cpu], cpu_set_size,
598 						cpu_set)) {
599 					fprintf(stderr, "Any given CPU may "
600 						"only be given once.\n");
601 					goto err_code;
602 				} else
603 					CPU_SET_S(cpus_to_pin[cpu],
604 						  cpu_set_size, cpu_set);
605 			}
606 			break;
607 		case 'p':
608 			/*
609 			 * Although we can create a msg queue with a
610 			 * non-absolute path name, unlink will fail.  So,
611 			 * if the name doesn't start with a /, add one
612 			 * when we save it.
613 			 */
614 			option = queue_path;
615 			if (*option != '/') {
616 				queue_path = malloc(strlen(option) + 2);
617 				if (!queue_path) {
618 					perror("malloc()");
619 					goto err_code;
620 				}
621 				queue_path[0] = '/';
622 				queue_path[1] = 0;
623 				strcat(queue_path, option);
624 				free(option);
625 			}
626 			break;
627 		}
628 	}
629 
630 	if (continuous_mode && num_cpus_to_pin == 0) {
631 		fprintf(stderr, "Must pass at least one CPU to continuous "
632 			"mode.\n");
633 		poptPrintUsage(popt_context, stderr, 0);
634 		goto err_code;
635 	} else if (!continuous_mode) {
636 		num_cpus_to_pin = 1;
637 		cpus_to_pin[0] = cpus_online - 1;
638 	}
639 
640 	max_msgs = fopen(MAX_MSGS, "r+");
641 	max_msgsize = fopen(MAX_MSGSIZE, "r+");
642 	if (!max_msgs)
643 		shutdown(2, "Failed to open msg_max", __LINE__);
644 	if (!max_msgsize)
645 		shutdown(2, "Failed to open msgsize_max", __LINE__);
646 
647 	/* Load up the current system values for everything we can */
648 	getr(RLIMIT_MSGQUEUE, &saved_limits);
649 	cur_limits = saved_limits;
650 	saved_max_msgs = cur_max_msgs = get(max_msgs);
651 	saved_max_msgsize = cur_max_msgsize = get(max_msgsize);
652 	errno = 0;
653 	cur_nice = getpriority(PRIO_PROCESS, 0);
654 	if (errno)
655 		shutdown(2, "getpriority()", __LINE__);
656 
657 	/* Tell the user our initial state */
658 	printf("\nInitial system state:\n");
659 	printf("\tUsing queue path:\t\t\t%s\n", queue_path);
660 	printf("\tRLIMIT_MSGQUEUE(soft):\t\t\t%ld\n",
661 		(long) saved_limits.rlim_cur);
662 	printf("\tRLIMIT_MSGQUEUE(hard):\t\t\t%ld\n",
663 		(long) saved_limits.rlim_max);
664 	printf("\tMaximum Message Size:\t\t\t%d\n", saved_max_msgsize);
665 	printf("\tMaximum Queue Size:\t\t\t%d\n", saved_max_msgs);
666 	printf("\tNice value:\t\t\t\t%d\n", cur_nice);
667 	printf("\n");
668 
669 	increase_limits();
670 
671 	printf("Adjusted system state for testing:\n");
672 	if (cur_limits.rlim_cur == RLIM_INFINITY) {
673 		printf("\tRLIMIT_MSGQUEUE(soft):\t\t\t(unlimited)\n");
674 		printf("\tRLIMIT_MSGQUEUE(hard):\t\t\t(unlimited)\n");
675 	} else {
676 		printf("\tRLIMIT_MSGQUEUE(soft):\t\t\t%ld\n",
677 		       (long) cur_limits.rlim_cur);
678 		printf("\tRLIMIT_MSGQUEUE(hard):\t\t\t%ld\n",
679 		       (long) cur_limits.rlim_max);
680 	}
681 	printf("\tMaximum Message Size:\t\t\t%d\n", cur_max_msgsize);
682 	printf("\tMaximum Queue Size:\t\t\t%d\n", cur_max_msgs);
683 	printf("\tNice value:\t\t\t\t%d\n", cur_nice);
684 	printf("\tContinuous mode:\t\t\t(%s)\n", continuous_mode ?
685 	       (continuous_mode_fake ? "fake mode" : "enabled") :
686 	       "disabled");
687 	printf("\tCPUs to pin:\t\t\t\t%d", cpus_to_pin[0]);
688 	for (cpu = 1; cpu < num_cpus_to_pin; cpu++)
689 			printf(",%d", cpus_to_pin[cpu]);
690 	printf("\n");
691 
692 	sa.sa_sigaction = sig_action_SIGUSR1;
693 	sigemptyset(&sa.sa_mask);
694 	sigaddset(&sa.sa_mask, SIGHUP);
695 	sigaddset(&sa.sa_mask, SIGINT);
696 	sigaddset(&sa.sa_mask, SIGQUIT);
697 	sigaddset(&sa.sa_mask, SIGTERM);
698 	sa.sa_flags = SA_SIGINFO;
699 	if (sigaction(SIGUSR1, &sa, NULL) == -1)
700 		shutdown(1, "sigaction(SIGUSR1)", __LINE__);
701 	sa.sa_sigaction = sig_action;
702 	if (sigaction(SIGHUP, &sa, NULL) == -1)
703 		shutdown(1, "sigaction(SIGHUP)", __LINE__);
704 	if (sigaction(SIGINT, &sa, NULL) == -1)
705 		shutdown(1, "sigaction(SIGINT)", __LINE__);
706 	if (sigaction(SIGQUIT, &sa, NULL) == -1)
707 		shutdown(1, "sigaction(SIGQUIT)", __LINE__);
708 	if (sigaction(SIGTERM, &sa, NULL) == -1)
709 		shutdown(1, "sigaction(SIGTERM)", __LINE__);
710 
711 	if (!continuous_mode_fake) {
712 		attr.mq_flags = O_NONBLOCK;
713 		attr.mq_maxmsg = cur_max_msgs;
714 		attr.mq_msgsize = MSG_SIZE;
715 		open_queue(&attr);
716 	}
717 	for (i = 0; i < num_cpus_to_pin; i++) {
718 		pthread_attr_t thread_attr;
719 		void *thread_func;
720 
721 		if (continuous_mode_fake)
722 			thread_func = &fake_cont_thread;
723 		else if (continuous_mode)
724 			thread_func = &cont_thread;
725 		else
726 			thread_func = &perf_test_thread;
727 
728 		CPU_ZERO_S(cpu_set_size, cpu_set);
729 		CPU_SET_S(cpus_to_pin[i], cpu_set_size, cpu_set);
730 		pthread_attr_init(&thread_attr);
731 		pthread_attr_setaffinity_np(&thread_attr, cpu_set_size,
732 					    cpu_set);
733 		if (pthread_create(&cpu_threads[i], &thread_attr, thread_func,
734 				   NULL))
735 			shutdown(1, "pthread_create()", __LINE__);
736 		pthread_attr_destroy(&thread_attr);
737 	}
738 
739 	if (!continuous_mode) {
740 		pthread_join(cpu_threads[0], &retval);
741 		shutdown((long)retval, "perf_test_thread()", __LINE__);
742 	} else {
743 		while (1)
744 			sleep(1);
745 	}
746 	shutdown(0, "", 0);
747 
748 err_code:
749 	CPU_FREE(cpu_set);
750 	exit(1);
751 
752 }
753