tools/testing/selftests/mqueue/mq_perf_tests.c

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