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         if (lttng_poll_set_max_size()) {
 350                 retval = -1;
 351                 goto exit_init_data;
 352         }
 353
 354         if (*command_sock_path == '\0') {
 355                 switch (opt_type) {
 356                 case LTTNG_CONSUMER_KERNEL:
 357                         ret = snprintf(command_sock_path, PATH_MAX,
 358                                         DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
 359                                         DEFAULT_LTTNG_RUNDIR);
 360                         if (ret < 0) {
 361                                 retval = -1;
 362                                 goto exit_init_data;
 363                         }
 364                         break;
 365                 case LTTNG_CONSUMER64_UST:
 366                         ret = snprintf(command_sock_path, PATH_MAX,
 367                                         DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
 368                                         DEFAULT_LTTNG_RUNDIR);
 369                         if (ret < 0) {
 370                                 retval = -1;
 371                                 goto exit_init_data;
 372                         }
 373                         break;
 374                 case LTTNG_CONSUMER32_UST:
 375                         ret = snprintf(command_sock_path, PATH_MAX,
 376                                         DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
 377                                         DEFAULT_LTTNG_RUNDIR);
 378                         if (ret < 0) {
 379                                 retval = -1;
 380                                 goto exit_init_data;
 381                         }
 382                         break;
 383                 default:
 384                         ERR("Unknown consumerd type");
 385                         retval = -1;
 386                         goto exit_init_data;
 387                 }
 388         }
 389
 390         /* Init */
 391         if (lttng_consumer_init()) {
 392                 retval = -1;
 393                 goto exit_init_data;
 394         }
 395
 396         /* Initialize communication library */
 397         lttcomm_init();
 398         /* Initialize TCP timeout values */
 399         lttcomm_inet_init();
 400
 401         if (!getuid()) {
 402                 /* Set limit for open files */
 403                 set_ulimit();
 404         }
 405
 406         /* create the consumer instance with and assign the callbacks */
 407         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 408                 NULL, lttng_consumer_on_recv_stream, NULL);
 409         if (!ctx) {
 410                 retval = -1;
 411                 goto exit_init_data;
 412         }
 413
 414         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 415         if (*error_sock_path == '\0') {
 416                 switch (opt_type) {
 417                 case LTTNG_CONSUMER_KERNEL:
 418                         ret = snprintf(error_sock_path, PATH_MAX,
 419                                         DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
 420                                         DEFAULT_LTTNG_RUNDIR);
 421                         if (ret < 0) {
 422                                 retval = -1;
 423                                 goto exit_init_data;
 424                         }
 425                         break;
 426                 case LTTNG_CONSUMER64_UST:
 427                         ret = snprintf(error_sock_path, PATH_MAX,
 428                                         DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
 429                                         DEFAULT_LTTNG_RUNDIR);
 430                         if (ret < 0) {
 431                                 retval = -1;
 432                                 goto exit_init_data;
 433                         }
 434                         break;
 435                 case LTTNG_CONSUMER32_UST:
 436                         ret = snprintf(error_sock_path, PATH_MAX,
 437                                         DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
 438                                         DEFAULT_LTTNG_RUNDIR);
 439                         if (ret < 0) {
 440                                 retval = -1;
 441                                 goto exit_init_data;
 442                         }
 443                         break;
 444                 default:
 445                         ERR("Unknown consumerd type");
 446                         retval = -1;
 447                         goto exit_init_data;
 448                 }
 449         }
 450
 451         /* Connect to the socket created by lttng-sessiond to report errors */
 452         DBG("Connecting to error socket %s", error_sock_path);
 453         ret = lttcomm_connect_unix_sock(error_sock_path);
 454         /*
 455          * Not a fatal error, but all communication with lttng-sessiond will
 456          * fail.
 457          */
 458         if (ret < 0) {
 459                 WARN("Cannot connect to error socket (is lttng-sessiond started?)");
 460         }
 461         lttng_consumer_set_error_sock(ctx, ret);
 462
 463         /*
 464          * Block RT signals used for UST periodical metadata flush and the live
 465          * timer in main, and create a dedicated thread to handle these signals.
 466          */
 467         if (consumer_signal_init()) {
 468                 retval = -1;
 469                 goto exit_init_data;
 470         }
 471
 472         ctx->type = opt_type;
 473
 474         if (utils_create_pipe(health_quit_pipe)) {
 475                 retval = -1;
 476                 goto exit_health_pipe;
 477         }
 478
 479         /* Create thread to manage the client socket */
 480         ret = pthread_create(&health_thread, NULL,
 481                         thread_manage_health, (void *) NULL);
 482         if (ret) {
 483                 errno = ret;
 484                 PERROR("pthread_create health");
 485                 retval = -1;
 486                 goto exit_health_thread;
 487         }
 488
 489         /*
 490          * Wait for health thread to be initialized before letting the
 491          * sessiond thread reply to the sessiond that we are ready.
 492          */
 493         while (uatomic_read(&lttng_consumer_ready)) {
 494                 usleep(100000);
 495         }
 496         cmm_smp_mb();   /* Read ready before following operations */
 497
 498         /* Create thread to manage channels */
 499         ret = pthread_create(&channel_thread, NULL,
 500                         consumer_thread_channel_poll,
 501                         (void *) ctx);
 502         if (ret) {
 503                 errno = ret;
 504                 PERROR("pthread_create");
 505                 retval = -1;
 506                 goto exit_channel_thread;
 507         }
 508
 509         /* Create thread to manage the polling/writing of trace metadata */
 510         ret = pthread_create(&metadata_thread, NULL,
 511                         consumer_thread_metadata_poll,
 512                         (void *) ctx);
 513         if (ret) {
 514                 errno = ret;
 515                 PERROR("pthread_create");
 516                 retval = -1;
 517                 goto exit_metadata_thread;
 518         }
 519
 520         /* Create thread to manage the polling/writing of trace data */
 521         ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
 522                         (void *) ctx);
 523         if (ret) {
 524                 errno = ret;
 525                 PERROR("pthread_create");
 526                 retval = -1;
 527                 goto exit_data_thread;
 528         }
 529
 530         /* Create the thread to manage the receive of fd */
 531         ret = pthread_create(&sessiond_thread, NULL,
 532                         consumer_thread_sessiond_poll,
 533                         (void *) ctx);
 534         if (ret) {
 535                 errno = ret;
 536                 PERROR("pthread_create");
 537                 retval = -1;
 538                 goto exit_sessiond_thread;
 539         }
 540
 541         /*
 542          * Create the thread to manage the UST metadata periodic timer and
 543          * live timer.
 544          */
 545         ret = pthread_create(&metadata_timer_thread, NULL,
 546                         consumer_timer_thread, (void *) ctx);
 547         if (ret) {
 548                 errno = ret;
 549                 PERROR("pthread_create");
 550                 retval = -1;
 551                 goto exit_metadata_timer_thread;
 552         }
 553
 554         ret = pthread_detach(metadata_timer_thread);
 555         if (ret) {
 556                 errno = ret;
 557                 PERROR("pthread_detach");
 558                 retval = -1;
 559                 goto exit_metadata_timer_detach;
 560         }
 561
 562         /*
 563          * This is where we start awaiting program completion (e.g. through
 564          * signal that asks threads to teardown.
 565          */
 566
 567 exit_metadata_timer_detach:
 568 exit_metadata_timer_thread:
 569         ret = pthread_join(sessiond_thread, &status);
 570         if (ret) {
 571                 errno = ret;
 572                 PERROR("pthread_join sessiond_thread");
 573                 retval = -1;
 574         }
 575 exit_sessiond_thread:
 576
 577         ret = pthread_join(data_thread, &status);
 578         if (ret) {
 579                 errno = ret;
 580                 PERROR("pthread_join data_thread");
 581                 retval = -1;
 582         }
 583 exit_data_thread:
 584
 585         ret = pthread_join(metadata_thread, &status);
 586         if (ret) {
 587                 errno = ret;
 588                 PERROR("pthread_join metadata_thread");
 589                 retval = -1;
 590         }
 591 exit_metadata_thread:
 592
 593         ret = pthread_join(channel_thread, &status);
 594         if (ret) {
 595                 errno = ret;
 596                 PERROR("pthread_join channel_thread");
 597                 retval = -1;
 598         }
 599 exit_channel_thread:
 600
 601         ret = pthread_join(health_thread, &status);
 602         if (ret) {
 603                 errno = ret;
 604                 PERROR("pthread_join health_thread");
 605                 retval = -1;
 606         }
 607 exit_health_thread:
 608
 609         utils_close_pipe(health_quit_pipe);
 610 exit_health_pipe:
 611
 612 exit_init_data:
 613         lttng_consumer_destroy(ctx);
 614         lttng_consumer_cleanup();
 615
 616         if (health_consumerd) {
 617                 health_app_destroy(health_consumerd);
 618         }
 619 exit_health_consumerd_cleanup:
 620
 621 exit_options:
 622
 623 exit_set_signal_handler:
 624         if (!retval) {
 625                 exit(EXIT_SUCCESS);
 626         } else {
 627                 exit(EXIT_FAILURE);
 628         }
 629 }