src/bin/lttng-consumerd/lttng-consumerd.c

   1 /*
   2  * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
   3  *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   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, version 2 only,
   7  * as published by the Free Software Foundation.
   8  *
   9  * This program 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  * You should have received a copy of the GNU General Public License along
  15  * with this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  */
  18
  19 #define _GNU_SOURCE
  20 #define _LGPL_SOURCE
  21 #include <fcntl.h>
  22 #include <getopt.h>
  23 #include <grp.h>
  24 #include <limits.h>
  25 #include <pthread.h>
  26 #include <signal.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <sys/ipc.h>
  31 #include <sys/resource.h>
  32 #include <sys/shm.h>
  33 #include <sys/socket.h>
  34 #include <sys/stat.h>
  35 #include <sys/types.h>
  36 #include <urcu/list.h>
  37 #include <poll.h>
  38 #include <unistd.h>
  39 #include <sys/mman.h>
  40 #include <assert.h>
  41 #include <config.h>
  42 #include <urcu/compiler.h>
  43 #include <ulimit.h>
  44
  45 #include <common/defaults.h>
  46 #include <common/common.h>
  47 #include <common/consumer.h>
  48 #include <common/consumer-timer.h>
  49 #include <common/compat/poll.h>
  50 #include <common/sessiond-comm/sessiond-comm.h>
  51 #include <common/utils.h>
  52
  53 #include "lttng-consumerd.h"
  54 #include "health-consumerd.h"
  55
  56 /* TODO : support UST (all direct kernel-ctl accesses). */
  57
  58 /* threads (channel handling, poll, metadata, sessiond) */
  59
  60 static pthread_t channel_thread, data_thread, metadata_thread,
  61                 sessiond_thread, metadata_timer_thread, health_thread;
  62
  63 /* to count the number of times the user pressed ctrl+c */
  64 static int sigintcount = 0;
  65
  66 /* Argument variables */
  67 int lttng_opt_quiet;    /* not static in error.h */
  68 int lttng_opt_verbose;  /* not static in error.h */
  69 int lttng_opt_mi;       /* not static in error.h */
  70
  71 static int opt_daemon;
  72 static const char *progname;
  73 static char command_sock_path[PATH_MAX]; /* Global command socket path */
  74 static char error_sock_path[PATH_MAX]; /* Global error path */
  75 static enum lttng_consumer_type opt_type = LTTNG_CONSUMER_KERNEL;
  76
  77 /* the liblttngconsumerd context */
  78 static struct lttng_consumer_local_data *ctx;
  79
  80 /* Consumerd health monitoring */
  81 struct health_app *health_consumerd;
  82
  83 const char *tracing_group_name = DEFAULT_TRACING_GROUP;
  84
  85 int lttng_consumer_ready = NR_LTTNG_CONSUMER_READY;
  86
  87 enum lttng_consumer_type lttng_consumer_get_type(void)
  88 {
  89         if (!ctx) {
  90                 return LTTNG_CONSUMER_UNKNOWN;
  91         }
  92         return ctx->type;
  93 }
  94
  95 /*
  96  * Signal handler for the daemon
  97  */
  98 static void sighandler(int sig)
  99 {
 100         if (sig == SIGINT && sigintcount++ == 0) {
 101                 DBG("ignoring first SIGINT");
 102                 return;
 103         }
 104
 105         /*
 106          * Ignore SIGPIPE because it should not stop the consumer whenever a
 107          * SIGPIPE is catched through a FD operation.
 108          */
 109         if (sig == SIGPIPE) {
 110                 return;
 111         }
 112
 113         lttng_consumer_should_exit(ctx);
 114 }
 115
 116 /*
 117  * Setup signal handler for :
 118  *      SIGINT, SIGTERM, SIGPIPE
 119  */
 120 static int set_signal_handler(void)
 121 {
 122         int ret = 0;
 123         struct sigaction sa;
 124         sigset_t sigset;
 125
 126         if ((ret = sigemptyset(&sigset)) < 0) {
 127                 perror("sigemptyset");
 128                 return ret;
 129         }
 130
 131         sa.sa_handler = sighandler;
 132         sa.sa_mask = sigset;
 133         sa.sa_flags = 0;
 134         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 135                 perror("sigaction");
 136                 return ret;
 137         }
 138
 139         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 140                 perror("sigaction");
 141                 return ret;
 142         }
 143
 144         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
 145                 perror("sigaction");
 146                 return ret;
 147         }
 148
 149         return ret;
 150 }
 151
 152 /*
 153  * Usage function on stream file.
 154  */
 155 static void usage(FILE *fp)
 156 {
 157         fprintf(fp, "Usage: %s OPTIONS\n\nOptions:\n", progname);
 158         fprintf(fp, "  -h, --help                         "
 159                         "Display this usage.\n");
 160         fprintf(fp, "  -c, --consumerd-cmd-sock PATH      "
 161                         "Specify path for the command socket\n");
 162         fprintf(fp, "  -e, --consumerd-err-sock PATH      "
 163                         "Specify path for the error socket\n");
 164         fprintf(fp, "  -d, --daemonize                    "
 165                         "Start as a daemon.\n");
 166         fprintf(fp, "  -q, --quiet                        "
 167                         "No output at all.\n");
 168         fprintf(fp, "  -v, --verbose                      "
 169                         "Verbose mode. Activate DBG() macro.\n");
 170         fprintf(fp, "  -V, --version                      "
 171                         "Show version number.\n");
 172         fprintf(fp, "  -g, --group NAME                   "
 173                         "Specify the tracing group name. (default: tracing)\n");
 174         fprintf(fp, "  -k, --kernel                       "
 175                         "Consumer kernel buffers (default).\n");
 176         fprintf(fp, "  -u, --ust                          "
 177                         "Consumer UST buffers.%s\n",
 178 #ifdef HAVE_LIBLTTNG_UST_CTL
 179                         ""
 180 #else
 181                         " (support not compiled in)"
 182 #endif
 183                         );
 184 }
 185
 186 /*
 187  * daemon argument parsing
 188  */
 189 static int parse_args(int argc, char **argv)
 190 {
 191         int c, ret = 0;
 192
 193         static struct option long_options[] = {
 194                 { "consumerd-cmd-sock", 1, 0, 'c' },
 195                 { "consumerd-err-sock", 1, 0, 'e' },
 196                 { "daemonize", 0, 0, 'd' },
 197                 { "group", 1, 0, 'g' },
 198                 { "help", 0, 0, 'h' },
 199                 { "quiet", 0, 0, 'q' },
 200                 { "verbose", 0, 0, 'v' },
 201                 { "version", 0, 0, 'V' },
 202                 { "kernel", 0, 0, 'k' },
 203 #ifdef HAVE_LIBLTTNG_UST_CTL
 204                 { "ust", 0, 0, 'u' },
 205 #endif
 206                 { NULL, 0, 0, 0 }
 207         };
 208
 209         while (1) {
 210                 int option_index = 0;
 211                 c = getopt_long(argc, argv, "dhqvVku" "c:e:g:", long_options, &option_index);
 212                 if (c == -1) {
 213                         break;
 214                 }
 215
 216                 switch (c) {
 217                 case 0:
 218                         fprintf(stderr, "option %s", long_options[option_index].name);
 219                         if (optarg) {
 220                                 fprintf(stderr, " with arg %s\n", optarg);
 221                                 ret = -1;
 222                                 goto end;
 223                         }
 224                         break;
 225                 case 'c':
 226                         snprintf(command_sock_path, PATH_MAX, "%s", optarg);
 227                         break;
 228                 case 'e':
 229                         snprintf(error_sock_path, PATH_MAX, "%s", optarg);
 230                         break;
 231                 case 'd':
 232                         opt_daemon = 1;
 233                         break;
 234                 case 'g':
 235                         tracing_group_name = optarg;
 236                         break;
 237                 case 'h':
 238                         usage(stdout);
 239                         exit(EXIT_SUCCESS);
 240                 case 'q':
 241                         lttng_opt_quiet = 1;
 242                         break;
 243                 case 'v':
 244                         lttng_opt_verbose = 1;
 245                         break;
 246                 case 'V':
 247                         fprintf(stdout, "%s\n", VERSION);
 248                         exit(EXIT_SUCCESS);
 249                 case 'k':
 250                         opt_type = LTTNG_CONSUMER_KERNEL;
 251                         break;
 252 #ifdef HAVE_LIBLTTNG_UST_CTL
 253                 case 'u':
 254 # if (CAA_BITS_PER_LONG == 64)
 255                         opt_type = LTTNG_CONSUMER64_UST;
 256 # elif (CAA_BITS_PER_LONG == 32)
 257                         opt_type = LTTNG_CONSUMER32_UST;
 258 # else
 259 #  error "Unknown bitness"
 260 # endif
 261                         break;
 262 #endif
 263                 default:
 264                         usage(stderr);
 265                         ret = -1;
 266                         goto end;
 267                 }
 268         }
 269 end:
 270         return ret;
 271 }
 272
 273 /*
 274  * Set open files limit to unlimited. This daemon can open a large number of
 275  * file descriptors in order to consumer multiple kernel traces.
 276  */
 277 static void set_ulimit(void)
 278 {
 279         int ret;
 280         struct rlimit lim;
 281
 282         /* The kernel does not allowed an infinite limit for open files */
 283         lim.rlim_cur = 65535;
 284         lim.rlim_max = 65535;
 285
 286         ret = setrlimit(RLIMIT_NOFILE, &lim);
 287         if (ret < 0) {
 288                 PERROR("failed to set open files limit");
 289         }
 290 }
 291
 292 /*
 293  * main
 294  */
 295 int main(int argc, char **argv)
 296 {
 297         int ret = 0;
 298         void *status;
 299
 300         /* Parse arguments */
 301         progname = argv[0];
 302         parse_args(argc, argv);
 303
 304         /* Daemonize */
 305         if (opt_daemon) {
 306                 int i;
 307
 308                 /*
 309                  * fork
 310                  * child: setsid, close FD 0, 1, 2, chdir /
 311                  * parent: exit (if fork is successful)
 312                  */
 313                 ret = daemon(0, 0);
 314                 if (ret < 0) {
 315                         PERROR("daemon");
 316                         goto error;
 317                 }
 318                 /*
 319                  * We are in the child. Make sure all other file
 320                  * descriptors are closed, in case we are called with
 321                  * more opened file descriptors than the standard ones.
 322                  */
 323                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
 324                         (void) close(i);
 325                 }
 326         }
 327
 328         /* Set up max poll set size */
 329         lttng_poll_set_max_size();
 330
 331         if (*command_sock_path == '\0') {
 332                 switch (opt_type) {
 333                 case LTTNG_CONSUMER_KERNEL:
 334                         snprintf(command_sock_path, PATH_MAX, DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
 335                                         DEFAULT_LTTNG_RUNDIR);
 336                         break;
 337                 case LTTNG_CONSUMER64_UST:
 338                         snprintf(command_sock_path, PATH_MAX,
 339                                         DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 340                         break;
 341                 case LTTNG_CONSUMER32_UST:
 342                         snprintf(command_sock_path, PATH_MAX,
 343                                         DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 344                         break;
 345                 default:
 346                         WARN("Unknown consumerd type");
 347                         goto error;
 348                 }
 349         }
 350
 351         /* Init */
 352         if (lttng_consumer_init() < 0) {
 353                 goto error;
 354         }
 355
 356         /* Init socket timeouts */
 357         lttcomm_init();
 358         lttcomm_inet_init();
 359
 360         if (!getuid()) {
 361                 /* Set limit for open files */
 362                 set_ulimit();
 363         }
 364
 365         health_consumerd = health_app_create(NR_HEALTH_CONSUMERD_TYPES);
 366         if (!health_consumerd) {
 367                 goto error;
 368         }
 369
 370         /* create the consumer instance with and assign the callbacks */
 371         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 372                 NULL, lttng_consumer_on_recv_stream, NULL);
 373         if (ctx == NULL) {
 374                 goto error;
 375         }
 376
 377         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 378         if (*error_sock_path == '\0') {
 379                 switch (opt_type) {
 380                 case LTTNG_CONSUMER_KERNEL:
 381                         snprintf(error_sock_path, PATH_MAX, DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
 382                                         DEFAULT_LTTNG_RUNDIR);
 383                         break;
 384                 case LTTNG_CONSUMER64_UST:
 385                         snprintf(error_sock_path, PATH_MAX,
 386                                         DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 387                         break;
 388                 case LTTNG_CONSUMER32_UST:
 389                         snprintf(error_sock_path, PATH_MAX,
 390                                         DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 391                         break;
 392                 default:
 393                         WARN("Unknown consumerd type");
 394                         goto error;
 395                 }
 396         }
 397
 398         if (set_signal_handler() < 0) {
 399                 goto error;
 400         }
 401
 402         /* Connect to the socket created by lttng-sessiond to report errors */
 403         DBG("Connecting to error socket %s", error_sock_path);
 404         ret = lttcomm_connect_unix_sock(error_sock_path);
 405         /* not a fatal error, but all communication with lttng-sessiond will fail */
 406         if (ret < 0) {
 407                 WARN("Cannot connect to error socket (is lttng-sessiond started?)");
 408         }
 409         lttng_consumer_set_error_sock(ctx, ret);
 410
 411         /*
 412          * Block RT signals used for UST periodical metadata flush and the live
 413          * timer in main, and create a dedicated thread to handle these signals.
 414          */
 415         consumer_signal_init();
 416
 417         ctx->type = opt_type;
 418
 419         ret = utils_create_pipe(health_quit_pipe);
 420         if (ret < 0) {
 421                 goto error_health_pipe;
 422         }
 423
 424         /* Create thread to manage the client socket */
 425         ret = pthread_create(&health_thread, NULL,
 426                         thread_manage_health, (void *) NULL);
 427         if (ret != 0) {
 428                 PERROR("pthread_create health");
 429                 goto health_error;
 430         }
 431
 432         /*
 433          * Wait for health thread to be initialized before letting the
 434          * sessiond thread reply to the sessiond that we are ready.
 435          */
 436         while (uatomic_read(&lttng_consumer_ready)) {
 437                 usleep(100000);
 438         }
 439         cmm_smp_mb();   /* Read ready before following operations */
 440
 441         /* Create thread to manage channels */
 442         ret = pthread_create(&channel_thread, NULL, consumer_thread_channel_poll,
 443                         (void *) ctx);
 444         if (ret != 0) {
 445                 perror("pthread_create");
 446                 goto channel_error;
 447         }
 448
 449         /* Create thread to manage the polling/writing of trace metadata */
 450         ret = pthread_create(&metadata_thread, NULL, consumer_thread_metadata_poll,
 451                         (void *) ctx);
 452         if (ret != 0) {
 453                 perror("pthread_create");
 454                 goto metadata_error;
 455         }
 456
 457         /* Create thread to manage the polling/writing of trace data */
 458         ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
 459                         (void *) ctx);
 460         if (ret != 0) {
 461                 perror("pthread_create");
 462                 goto data_error;
 463         }
 464
 465         /* Create the thread to manage the receive of fd */
 466         ret = pthread_create(&sessiond_thread, NULL, consumer_thread_sessiond_poll,
 467                         (void *) ctx);
 468         if (ret != 0) {
 469                 perror("pthread_create");
 470                 goto sessiond_error;
 471         }
 472
 473         /*
 474          * Create the thread to manage the UST metadata periodic timer and
 475          * live timer.
 476          */
 477         ret = pthread_create(&metadata_timer_thread, NULL,
 478                         consumer_timer_thread, (void *) ctx);
 479         if (ret != 0) {
 480                 perror("pthread_create");
 481                 goto metadata_timer_error;
 482         }
 483
 484         ret = pthread_detach(metadata_timer_thread);
 485         if (ret) {
 486                 errno = ret;
 487                 perror("pthread_detach");
 488         }
 489
 490 metadata_timer_error:
 491         ret = pthread_join(sessiond_thread, &status);
 492         if (ret != 0) {
 493                 perror("pthread_join");
 494                 goto error;
 495         }
 496
 497 sessiond_error:
 498         ret = pthread_join(data_thread, &status);
 499         if (ret != 0) {
 500                 perror("pthread_join");
 501                 goto error;
 502         }
 503
 504 data_error:
 505         ret = pthread_join(metadata_thread, &status);
 506         if (ret != 0) {
 507                 perror("pthread_join");
 508                 goto error;
 509         }
 510
 511 metadata_error:
 512         ret = pthread_join(channel_thread, &status);
 513         if (ret != 0) {
 514                 perror("pthread_join");
 515                 goto error;
 516         }
 517
 518 channel_error:
 519         ret = pthread_join(health_thread, &status);
 520         if (ret != 0) {
 521                 PERROR("pthread_join health thread");
 522                 goto error;     /* join error, exit without cleanup */
 523         }
 524
 525 health_error:
 526         utils_close_pipe(health_quit_pipe);
 527
 528 error_health_pipe:
 529         if (!ret) {
 530                 ret = EXIT_SUCCESS;
 531                 goto end;
 532         }
 533
 534 error:
 535         ret = EXIT_FAILURE;
 536
 537 end:
 538         lttng_consumer_destroy(ctx);
 539         lttng_consumer_cleanup();
 540         if (health_consumerd) {
 541                 health_app_destroy(health_consumerd);
 542         }
 543
 544         return ret;
 545 }