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 /* threads (channel handling, poll, metadata, sessiond) */
  57
  58 static pthread_t channel_thread, data_thread, metadata_thread,
  59                 sessiond_thread, metadata_timer_thread, health_thread;
  60
  61 /* to count the number of times the user pressed ctrl+c */
  62 static int sigintcount = 0;
  63
  64 /* Argument variables */
  65 int lttng_opt_quiet;    /* not static in error.h */
  66 int lttng_opt_verbose;  /* not static in error.h */
  67 int lttng_opt_mi;       /* not static in error.h */
  68
  69 static int opt_daemon;
  70 static const char *progname;
  71 static char command_sock_path[PATH_MAX]; /* Global command socket path */
  72 static char error_sock_path[PATH_MAX]; /* Global error path */
  73 static enum lttng_consumer_type opt_type = LTTNG_CONSUMER_KERNEL;
  74
  75 /* the liblttngconsumerd context */
  76 static struct lttng_consumer_local_data *ctx;
  77
  78 /* Consumerd health monitoring */
  79 struct health_app *health_consumerd;
  80
  81 const char *tracing_group_name = DEFAULT_TRACING_GROUP;
  82
  83 int lttng_consumer_ready = NR_LTTNG_CONSUMER_READY;
  84
  85 enum lttng_consumer_type lttng_consumer_get_type(void)
  86 {
  87         if (!ctx) {
  88                 return LTTNG_CONSUMER_UNKNOWN;
  89         }
  90         return ctx->type;
  91 }
  92
  93 /*
  94  * Signal handler for the daemon
  95  */
  96 static void sighandler(int sig)
  97 {
  98         if (sig == SIGINT && sigintcount++ == 0) {
  99                 DBG("ignoring first SIGINT");
 100                 return;
 101         }
 102
 103         /*
 104          * Ignore SIGPIPE because it should not stop the consumer whenever a
 105          * SIGPIPE is catched through a FD operation.
 106          */
 107         if (sig == SIGPIPE) {
 108                 return;
 109         }
 110
 111         lttng_consumer_should_exit(ctx);
 112 }
 113
 114 /*
 115  * Setup signal handler for :
 116  *      SIGINT, SIGTERM, SIGPIPE
 117  */
 118 static int set_signal_handler(void)
 119 {
 120         int ret = 0;
 121         struct sigaction sa;
 122         sigset_t sigset;
 123
 124         if ((ret = sigemptyset(&sigset)) < 0) {
 125                 PERROR("sigemptyset");
 126                 return ret;
 127         }
 128
 129         sa.sa_handler = sighandler;
 130         sa.sa_mask = sigset;
 131         sa.sa_flags = 0;
 132         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 133                 PERROR("sigaction");
 134                 return ret;
 135         }
 136
 137         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 138                 PERROR("sigaction");
 139                 return ret;
 140         }
 141
 142         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
 143                 PERROR("sigaction");
 144                 return ret;
 145         }
 146
 147         return ret;
 148 }
 149
 150 /*
 151  * Usage function on stream file.
 152  */
 153 static void usage(FILE *fp)
 154 {
 155         fprintf(fp, "Usage: %s OPTIONS\n\nOptions:\n", progname);
 156         fprintf(fp, "  -h, --help                         "
 157                         "Display this usage.\n");
 158         fprintf(fp, "  -c, --consumerd-cmd-sock PATH      "
 159                         "Specify path for the command socket\n");
 160         fprintf(fp, "  -e, --consumerd-err-sock PATH      "
 161                         "Specify path for the error socket\n");
 162         fprintf(fp, "  -d, --daemonize                    "
 163                         "Start as a daemon.\n");
 164         fprintf(fp, "  -q, --quiet                        "
 165                         "No output at all.\n");
 166         fprintf(fp, "  -v, --verbose                      "
 167                         "Verbose mode. Activate DBG() macro.\n");
 168         fprintf(fp, "  -V, --version                      "
 169                         "Show version number.\n");
 170         fprintf(fp, "  -g, --group NAME                   "
 171                         "Specify the tracing group name. (default: tracing)\n");
 172         fprintf(fp, "  -k, --kernel                       "
 173                         "Consumer kernel buffers (default).\n");
 174         fprintf(fp, "  -u, --ust                          "
 175                         "Consumer UST buffers.%s\n",
 176 #ifdef HAVE_LIBLTTNG_UST_CTL
 177                         ""
 178 #else
 179                         " (support not compiled in)"
 180 #endif
 181                         );
 182 }
 183
 184 /*
 185  * daemon argument parsing
 186  */
 187 static int parse_args(int argc, char **argv)
 188 {
 189         int c, ret = 0;
 190
 191         static struct option long_options[] = {
 192                 { "consumerd-cmd-sock", 1, 0, 'c' },
 193                 { "consumerd-err-sock", 1, 0, 'e' },
 194                 { "daemonize", 0, 0, 'd' },
 195                 { "group", 1, 0, 'g' },
 196                 { "help", 0, 0, 'h' },
 197                 { "quiet", 0, 0, 'q' },
 198                 { "verbose", 0, 0, 'v' },
 199                 { "version", 0, 0, 'V' },
 200                 { "kernel", 0, 0, 'k' },
 201 #ifdef HAVE_LIBLTTNG_UST_CTL
 202                 { "ust", 0, 0, 'u' },
 203 #endif
 204                 { NULL, 0, 0, 0 }
 205         };
 206
 207         while (1) {
 208                 int option_index = 0;
 209                 c = getopt_long(argc, argv, "dhqvVku" "c:e:g:",
 210                                 long_options, &option_index);
 211                 if (c == -1) {
 212                         break;
 213                 }
 214
 215                 switch (c) {
 216                 case 0:
 217                         fprintf(stderr, "option %s",
 218                                 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, retval = 0;
 298         void *status;
 299
 300         if (set_signal_handler()) {
 301                 retval = -1;
 302                 goto exit_set_signal_handler;
 303         }
 304
 305         /* Parse arguments */
 306         progname = argv[0];
 307         if (parse_args(argc, argv)) {
 308                 retval = -1;
 309                 goto exit_options;
 310         }
 311
 312         /* Daemonize */
 313         if (opt_daemon) {
 314                 int i;
 315
 316                 /*
 317                  * fork
 318                  * child: setsid, close FD 0, 1, 2, chdir /
 319                  * parent: exit (if fork is successful)
 320                  */
 321                 ret = daemon(0, 0);
 322                 if (ret < 0) {
 323                         PERROR("daemon");
 324                         retval = -1;
 325                         goto exit_options;
 326                 }
 327                 /*
 328                  * We are in the child. Make sure all other file
 329                  * descriptors are closed, in case we are called with
 330                  * more opened file descriptors than the standard ones.
 331                  */
 332                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
 333                         (void) close(i);
 334                 }
 335         }
 336
 337         /*
 338          * Starting from here, we can create threads. This needs to be after
 339          * lttng_daemonize due to RCU.
 340          */
 341
 342         health_consumerd = health_app_create(NR_HEALTH_CONSUMERD_TYPES);
 343         if (!health_consumerd) {
 344                 retval = -1;
 345                 goto exit_health_consumerd_cleanup;
 346         }
 347
 348         /* Set up max poll set size */
 349         lttng_poll_set_max_size();
 350
 351         if (*command_sock_path == '\0') {
 352                 switch (opt_type) {
 353                 case LTTNG_CONSUMER_KERNEL:
 354                         ret = snprintf(command_sock_path, PATH_MAX,
 355                                         DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
 356                                         DEFAULT_LTTNG_RUNDIR);
 357                         if (ret < 0) {
 358                                 retval = -1;
 359                                 goto exit_init_data;
 360                         }
 361                         break;
 362                 case LTTNG_CONSUMER64_UST:
 363                         ret = snprintf(command_sock_path, PATH_MAX,
 364                                         DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
 365                                         DEFAULT_LTTNG_RUNDIR);
 366                         if (ret < 0) {
 367                                 retval = -1;
 368                                 goto exit_init_data;
 369                         }
 370                         break;
 371                 case LTTNG_CONSUMER32_UST:
 372                         ret = snprintf(command_sock_path, PATH_MAX,
 373                                         DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
 374                                         DEFAULT_LTTNG_RUNDIR);
 375                         if (ret < 0) {
 376                                 retval = -1;
 377                                 goto exit_init_data;
 378                         }
 379                         break;
 380                 default:
 381                         ERR("Unknown consumerd type");
 382                         retval = -1;
 383                         goto exit_init_data;
 384                 }
 385         }
 386
 387         /* Init */
 388         if (lttng_consumer_init()) {
 389                 retval = -1;
 390                 goto exit_init_data;
 391         }
 392
 393         /* Initialize communication library */
 394         lttcomm_init();
 395         /* Initialize TCP timeout values */
 396         lttcomm_inet_init();
 397
 398         if (!getuid()) {
 399                 /* Set limit for open files */
 400                 set_ulimit();
 401         }
 402
 403         /* create the consumer instance with and assign the callbacks */
 404         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 405                 NULL, lttng_consumer_on_recv_stream, NULL);
 406         if (!ctx) {
 407                 retval = -1;
 408                 goto exit_init_data;
 409         }
 410
 411         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 412         if (*error_sock_path == '\0') {
 413                 switch (opt_type) {
 414                 case LTTNG_CONSUMER_KERNEL:
 415                         ret = snprintf(error_sock_path, PATH_MAX,
 416                                         DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
 417                                         DEFAULT_LTTNG_RUNDIR);
 418                         if (ret < 0) {
 419                                 retval = -1;
 420                                 goto exit_init_data;
 421                         }
 422                         break;
 423                 case LTTNG_CONSUMER64_UST:
 424                         ret = snprintf(error_sock_path, PATH_MAX,
 425                                         DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
 426                                         DEFAULT_LTTNG_RUNDIR);
 427                         if (ret < 0) {
 428                                 retval = -1;
 429                                 goto exit_init_data;
 430                         }
 431                         break;
 432                 case LTTNG_CONSUMER32_UST:
 433                         ret = snprintf(error_sock_path, PATH_MAX,
 434                                         DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
 435                                         DEFAULT_LTTNG_RUNDIR);
 436                         if (ret < 0) {
 437                                 retval = -1;
 438                                 goto exit_init_data;
 439                         }
 440                         break;
 441                 default:
 442                         ERR("Unknown consumerd type");
 443                         retval = -1;
 444                         goto exit_init_data;
 445                 }
 446         }
 447
 448         /* Connect to the socket created by lttng-sessiond to report errors */
 449         DBG("Connecting to error socket %s", error_sock_path);
 450         ret = lttcomm_connect_unix_sock(error_sock_path);
 451         /*
 452          * Not a fatal error, but all communication with lttng-sessiond will
 453          * fail.
 454          */
 455         if (ret < 0) {
 456                 WARN("Cannot connect to error socket (is lttng-sessiond started?)");
 457         }
 458         lttng_consumer_set_error_sock(ctx, ret);
 459
 460         /*
 461          * Block RT signals used for UST periodical metadata flush and the live
 462          * timer in main, and create a dedicated thread to handle these signals.
 463          */
 464         if (consumer_signal_init()) {
 465                 retval = -1;
 466                 goto exit_init_data;
 467         }
 468
 469         ctx->type = opt_type;
 470
 471         if (utils_create_pipe(health_quit_pipe)) {
 472                 retval = -1;
 473                 goto exit_health_pipe;
 474         }
 475
 476         /* Create thread to manage the client socket */
 477         ret = pthread_create(&health_thread, NULL,
 478                         thread_manage_health, (void *) NULL);
 479         if (ret) {
 480                 errno = ret;
 481                 PERROR("pthread_create health");
 482                 retval = -1;
 483                 goto exit_health_thread;
 484         }
 485
 486         /*
 487          * Wait for health thread to be initialized before letting the
 488          * sessiond thread reply to the sessiond that we are ready.
 489          */
 490         while (uatomic_read(&lttng_consumer_ready)) {
 491                 usleep(100000);
 492         }
 493         cmm_smp_mb();   /* Read ready before following operations */
 494
 495         /* Create thread to manage channels */
 496         ret = pthread_create(&channel_thread, NULL,
 497                         consumer_thread_channel_poll,
 498                         (void *) ctx);
 499         if (ret) {
 500                 errno = ret;
 501                 PERROR("pthread_create");
 502                 retval = -1;
 503                 goto exit_channel_thread;
 504         }
 505
 506         /* Create thread to manage the polling/writing of trace metadata */
 507         ret = pthread_create(&metadata_thread, NULL,
 508                         consumer_thread_metadata_poll,
 509                         (void *) ctx);
 510         if (ret) {
 511                 errno = ret;
 512                 PERROR("pthread_create");
 513                 retval = -1;
 514                 goto exit_metadata_thread;
 515         }
 516
 517         /* Create thread to manage the polling/writing of trace data */
 518         ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
 519                         (void *) ctx);
 520         if (ret) {
 521                 errno = ret;
 522                 PERROR("pthread_create");
 523                 retval = -1;
 524                 goto exit_data_thread;
 525         }
 526
 527         /* Create the thread to manage the receive of fd */
 528         ret = pthread_create(&sessiond_thread, NULL,
 529                         consumer_thread_sessiond_poll,
 530                         (void *) ctx);
 531         if (ret) {
 532                 errno = ret;
 533                 PERROR("pthread_create");
 534                 retval = -1;
 535                 goto exit_sessiond_thread;
 536         }
 537
 538         /*
 539          * Create the thread to manage the UST metadata periodic timer and
 540          * live timer.
 541          */
 542         ret = pthread_create(&metadata_timer_thread, NULL,
 543                         consumer_timer_thread, (void *) ctx);
 544         if (ret) {
 545                 errno = ret;
 546                 PERROR("pthread_create");
 547                 retval = -1;
 548                 goto exit_metadata_timer_thread;
 549         }
 550
 551         ret = pthread_detach(metadata_timer_thread);
 552         if (ret) {
 553                 errno = ret;
 554                 PERROR("pthread_detach");
 555                 retval = -1;
 556                 goto exit_metadata_timer_detach;
 557         }
 558
 559         /*
 560          * This is where we start awaiting program completion (e.g. through
 561          * signal that asks threads to teardown.
 562          */
 563
 564 exit_metadata_timer_detach:
 565 exit_metadata_timer_thread:
 566         ret = pthread_join(sessiond_thread, &status);
 567         if (ret) {
 568                 errno = ret;
 569                 PERROR("pthread_join sessiond_thread");
 570                 retval = -1;
 571         }
 572 exit_sessiond_thread:
 573
 574         ret = pthread_join(data_thread, &status);
 575         if (ret) {
 576                 errno = ret;
 577                 PERROR("pthread_join data_thread");
 578                 retval = -1;
 579         }
 580 exit_data_thread:
 581
 582         ret = pthread_join(metadata_thread, &status);
 583         if (ret) {
 584                 errno = ret;
 585                 PERROR("pthread_join metadata_thread");
 586                 retval = -1;
 587         }
 588 exit_metadata_thread:
 589
 590         ret = pthread_join(channel_thread, &status);
 591         if (ret) {
 592                 errno = ret;
 593                 PERROR("pthread_join channel_thread");
 594                 retval = -1;
 595         }
 596 exit_channel_thread:
 597
 598         ret = pthread_join(health_thread, &status);
 599         if (ret) {
 600                 errno = ret;
 601                 PERROR("pthread_join health_thread");
 602                 retval = -1;
 603         }
 604 exit_health_thread:
 605
 606         utils_close_pipe(health_quit_pipe);
 607 exit_health_pipe:
 608
 609 exit_init_data:
 610         lttng_consumer_destroy(ctx);
 611         lttng_consumer_cleanup();
 612
 613         if (health_consumerd) {
 614                 health_app_destroy(health_consumerd);
 615         }
 616 exit_health_consumerd_cleanup:
 617
 618 exit_options:
 619
 620 exit_set_signal_handler:
 621         if (!retval) {
 622                 exit(EXIT_SUCCESS);
 623         } else {
 624                 exit(EXIT_FAILURE);
 625         }
 626 }