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