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