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 int lttng_opt_mi;       /* not static in error.h */
  69
  70 static int opt_daemon;
  71 static const char *progname;
  72 static char command_sock_path[PATH_MAX]; /* Global command socket path */
  73 static char error_sock_path[PATH_MAX]; /* Global error path */
  74 static enum lttng_consumer_type opt_type = LTTNG_CONSUMER_KERNEL;
  75
  76 /* the liblttngconsumerd context */
  77 static struct lttng_consumer_local_data *ctx;
  78
  79 /* Consumerd health monitoring */
  80 struct health_app *health_consumerd;
  81
  82 const char *tracing_group_name = DEFAULT_TRACING_GROUP;
  83
  84 int lttng_consumer_ready = NR_LTTNG_CONSUMER_READY;
  85
  86 enum lttng_consumer_type lttng_consumer_get_type(void)
  87 {
  88         if (!ctx) {
  89                 return LTTNG_CONSUMER_UNKNOWN;
  90         }
  91         return ctx->type;
  92 }
  93
  94 /*
  95  * Signal handler for the daemon
  96  */
  97 static void sighandler(int sig)
  98 {
  99         if (sig == SIGINT && sigintcount++ == 0) {
 100                 DBG("ignoring first SIGINT");
 101                 return;
 102         }
 103
 104         /*
 105          * Ignore SIGPIPE because it should not stop the consumer whenever a
 106          * SIGPIPE is caught through a FD operation.
 107          */
 108         if (sig == SIGPIPE) {
 109                 return;
 110         }
 111
 112         if (ctx) {
 113                 lttng_consumer_should_exit(ctx);
 114         }
 115 }
 116
 117 /*
 118  * Setup signal handler for :
 119  *      SIGINT, SIGTERM, SIGPIPE
 120  */
 121 static int set_signal_handler(void)
 122 {
 123         int ret = 0;
 124         struct sigaction sa;
 125         sigset_t sigset;
 126
 127         if ((ret = sigemptyset(&sigset)) < 0) {
 128                 perror("sigemptyset");
 129                 return ret;
 130         }
 131
 132         sa.sa_handler = sighandler;
 133         sa.sa_mask = sigset;
 134         sa.sa_flags = 0;
 135         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 136                 perror("sigaction");
 137                 return ret;
 138         }
 139
 140         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 141                 perror("sigaction");
 142                 return ret;
 143         }
 144
 145         if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
 146                 perror("sigaction");
 147                 return ret;
 148         }
 149
 150         return ret;
 151 }
 152
 153 /*
 154  * Usage function on stream file.
 155  */
 156 static void usage(FILE *fp)
 157 {
 158         fprintf(fp, "Usage: %s OPTIONS\n\nOptions:\n", progname);
 159         fprintf(fp, "  -h, --help                         "
 160                         "Display this usage.\n");
 161         fprintf(fp, "  -c, --consumerd-cmd-sock PATH      "
 162                         "Specify path for the command socket\n");
 163         fprintf(fp, "  -e, --consumerd-err-sock PATH      "
 164                         "Specify path for the error socket\n");
 165         fprintf(fp, "  -d, --daemonize                    "
 166                         "Start as a daemon.\n");
 167         fprintf(fp, "  -q, --quiet                        "
 168                         "No output at all.\n");
 169         fprintf(fp, "  -v, --verbose                      "
 170                         "Verbose mode. Activate DBG() macro.\n");
 171         fprintf(fp, "  -V, --version                      "
 172                         "Show version number.\n");
 173         fprintf(fp, "  -g, --group NAME                   "
 174                         "Specify the tracing group name. (default: tracing)\n");
 175         fprintf(fp, "  -k, --kernel                       "
 176                         "Consumer kernel buffers (default).\n");
 177         fprintf(fp, "  -u, --ust                          "
 178                         "Consumer UST buffers.%s\n",
 179 #ifdef HAVE_LIBLTTNG_UST_CTL
 180                         ""
 181 #else
 182                         " (support not compiled in)"
 183 #endif
 184                         );
 185 }
 186
 187 /*
 188  * daemon argument parsing
 189  */
 190 static void parse_args(int argc, char **argv)
 191 {
 192         int c;
 193
 194         static struct option long_options[] = {
 195                 { "consumerd-cmd-sock", 1, 0, 'c' },
 196                 { "consumerd-err-sock", 1, 0, 'e' },
 197                 { "daemonize", 0, 0, 'd' },
 198                 { "group", 1, 0, 'g' },
 199                 { "help", 0, 0, 'h' },
 200                 { "quiet", 0, 0, 'q' },
 201                 { "verbose", 0, 0, 'v' },
 202                 { "version", 0, 0, 'V' },
 203                 { "kernel", 0, 0, 'k' },
 204 #ifdef HAVE_LIBLTTNG_UST_CTL
 205                 { "ust", 0, 0, 'u' },
 206 #endif
 207                 { NULL, 0, 0, 0 }
 208         };
 209
 210         while (1) {
 211                 int option_index = 0;
 212                 c = getopt_long(argc, argv, "dhqvVku" "c:e:g:", long_options, &option_index);
 213                 if (c == -1) {
 214                         break;
 215                 }
 216
 217                 switch (c) {
 218                 case 0:
 219                         fprintf(stderr, "option %s", long_options[option_index].name);
 220                         if (optarg) {
 221                                 fprintf(stderr, " with arg %s\n", optarg);
 222                         }
 223                         break;
 224                 case 'c':
 225                         snprintf(command_sock_path, PATH_MAX, "%s", optarg);
 226                         break;
 227                 case 'e':
 228                         snprintf(error_sock_path, PATH_MAX, "%s", optarg);
 229                         break;
 230                 case 'd':
 231                         opt_daemon = 1;
 232                         break;
 233                 case 'g':
 234                         tracing_group_name = optarg;
 235                         break;
 236                 case 'h':
 237                         usage(stdout);
 238                         exit(EXIT_SUCCESS);
 239                 case 'q':
 240                         lttng_opt_quiet = 1;
 241                         break;
 242                 case 'v':
 243                         lttng_opt_verbose = 1;
 244                         break;
 245                 case 'V':
 246                         fprintf(stdout, "%s\n", VERSION);
 247                         exit(EXIT_SUCCESS);
 248                 case 'k':
 249                         opt_type = LTTNG_CONSUMER_KERNEL;
 250                         break;
 251 #ifdef HAVE_LIBLTTNG_UST_CTL
 252                 case 'u':
 253 # if (CAA_BITS_PER_LONG == 64)
 254                         opt_type = LTTNG_CONSUMER64_UST;
 255 # elif (CAA_BITS_PER_LONG == 32)
 256                         opt_type = LTTNG_CONSUMER32_UST;
 257 # else
 258 #  error "Unknown bitness"
 259 # endif
 260                         break;
 261 #endif
 262                 default:
 263                         usage(stderr);
 264                         exit(EXIT_FAILURE);
 265                 }
 266         }
 267 }
 268
 269 /*
 270  * Set open files limit to unlimited. This daemon can open a large number of
 271  * file descriptors in order to consumer multiple kernel traces.
 272  */
 273 static void set_ulimit(void)
 274 {
 275         int ret;
 276         struct rlimit lim;
 277
 278         /* The kernel does not allowed an infinite limit for open files */
 279         lim.rlim_cur = 65535;
 280         lim.rlim_max = 65535;
 281
 282         ret = setrlimit(RLIMIT_NOFILE, &lim);
 283         if (ret < 0) {
 284                 PERROR("failed to set open files limit");
 285         }
 286 }
 287
 288 /*
 289  * main
 290  */
 291 int main(int argc, char **argv)
 292 {
 293         int ret = 0;
 294         void *status;
 295         struct lttng_consumer_local_data *tmp_ctx;
 296
 297         /* Parse arguments */
 298         progname = argv[0];
 299         parse_args(argc, argv);
 300
 301         /* Daemonize */
 302         if (opt_daemon) {
 303                 int i;
 304
 305                 /*
 306                  * fork
 307                  * child: setsid, close FD 0, 1, 2, chdir /
 308                  * parent: exit (if fork is successful)
 309                  */
 310                 ret = daemon(0, 0);
 311                 if (ret < 0) {
 312                         PERROR("daemon");
 313                         goto error;
 314                 }
 315                 /*
 316                  * We are in the child. Make sure all other file
 317                  * descriptors are closed, in case we are called with
 318                  * more opened file descriptors than the standard ones.
 319                  */
 320                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
 321                         (void) close(i);
 322                 }
 323         }
 324
 325         /* Set up max poll set size */
 326         lttng_poll_set_max_size();
 327
 328         if (*command_sock_path == '\0') {
 329                 switch (opt_type) {
 330                 case LTTNG_CONSUMER_KERNEL:
 331                         snprintf(command_sock_path, PATH_MAX, DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
 332                                         DEFAULT_LTTNG_RUNDIR);
 333                         break;
 334                 case LTTNG_CONSUMER64_UST:
 335                         snprintf(command_sock_path, PATH_MAX,
 336                                         DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 337                         break;
 338                 case LTTNG_CONSUMER32_UST:
 339                         snprintf(command_sock_path, PATH_MAX,
 340                                         DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 341                         break;
 342                 default:
 343                         WARN("Unknown consumerd type");
 344                         goto error;
 345                 }
 346         }
 347
 348         /* Init */
 349         if (lttng_consumer_init() < 0) {
 350                 goto error;
 351         }
 352
 353         /* Init socket timeouts */
 354         lttcomm_init();
 355         lttcomm_inet_init();
 356
 357         if (!getuid()) {
 358                 /* Set limit for open files */
 359                 set_ulimit();
 360         }
 361
 362         health_consumerd = health_app_create(NR_HEALTH_CONSUMERD_TYPES);
 363         if (!health_consumerd) {
 364                 goto error;
 365         }
 366
 367         /* create the consumer instance with and assign the callbacks */
 368         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 369                 NULL, lttng_consumer_on_recv_stream, NULL);
 370         if (ctx == NULL) {
 371                 goto error;
 372         }
 373
 374         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 375         if (*error_sock_path == '\0') {
 376                 switch (opt_type) {
 377                 case LTTNG_CONSUMER_KERNEL:
 378                         snprintf(error_sock_path, PATH_MAX, DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
 379                                         DEFAULT_LTTNG_RUNDIR);
 380                         break;
 381                 case LTTNG_CONSUMER64_UST:
 382                         snprintf(error_sock_path, PATH_MAX,
 383                                         DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 384                         break;
 385                 case LTTNG_CONSUMER32_UST:
 386                         snprintf(error_sock_path, PATH_MAX,
 387                                         DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH, DEFAULT_LTTNG_RUNDIR);
 388                         break;
 389                 default:
 390                         WARN("Unknown consumerd type");
 391                         goto error;
 392                 }
 393         }
 394
 395         if (set_signal_handler() < 0) {
 396                 goto error;
 397         }
 398
 399         /* Connect to the socket created by lttng-sessiond to report errors */
 400         DBG("Connecting to error socket %s", error_sock_path);
 401         ret = lttcomm_connect_unix_sock(error_sock_path);
 402         /* not a fatal error, but all communication with lttng-sessiond will fail */
 403         if (ret < 0) {
 404                 WARN("Cannot connect to error socket (is lttng-sessiond started?)");
 405         }
 406         lttng_consumer_set_error_sock(ctx, ret);
 407
 408         /*
 409          * Block RT signals used for UST periodical metadata flush and the live
 410          * timer in main, and create a dedicated thread to handle these signals.
 411          */
 412         consumer_signal_init();
 413
 414         ctx->type = opt_type;
 415
 416         ret = utils_create_pipe(health_quit_pipe);
 417         if (ret < 0) {
 418                 goto error_health_pipe;
 419         }
 420
 421         /* Create thread to manage the client socket */
 422         ret = pthread_create(&health_thread, NULL,
 423                         thread_manage_health, (void *) NULL);
 424         if (ret != 0) {
 425                 PERROR("pthread_create health");
 426                 goto health_error;
 427         }
 428
 429         /*
 430          * Wait for health thread to be initialized before letting the
 431          * sessiond thread reply to the sessiond that we are ready.
 432          */
 433         while (uatomic_read(&lttng_consumer_ready)) {
 434                 usleep(100000);
 435         }
 436         cmm_smp_mb();   /* Read ready before following operations */
 437
 438         /* Create thread to manage channels */
 439         ret = pthread_create(&channel_thread, NULL, consumer_thread_channel_poll,
 440                         (void *) ctx);
 441         if (ret != 0) {
 442                 perror("pthread_create");
 443                 goto channel_error;
 444         }
 445
 446         /* Create thread to manage the polling/writing of trace metadata */
 447         ret = pthread_create(&metadata_thread, NULL, consumer_thread_metadata_poll,
 448                         (void *) ctx);
 449         if (ret != 0) {
 450                 perror("pthread_create");
 451                 goto metadata_error;
 452         }
 453
 454         /* Create thread to manage the polling/writing of trace data */
 455         ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
 456                         (void *) ctx);
 457         if (ret != 0) {
 458                 perror("pthread_create");
 459                 goto data_error;
 460         }
 461
 462         /* Create the thread to manage the receive of fd */
 463         ret = pthread_create(&sessiond_thread, NULL, consumer_thread_sessiond_poll,
 464                         (void *) ctx);
 465         if (ret != 0) {
 466                 perror("pthread_create");
 467                 goto sessiond_error;
 468         }
 469
 470         /*
 471          * Create the thread to manage the UST metadata periodic timer and
 472          * live timer.
 473          */
 474         ret = pthread_create(&metadata_timer_thread, NULL,
 475                         consumer_timer_thread, (void *) ctx);
 476         if (ret != 0) {
 477                 perror("pthread_create");
 478                 goto metadata_timer_error;
 479         }
 480
 481         ret = pthread_detach(metadata_timer_thread);
 482         if (ret) {
 483                 errno = ret;
 484                 perror("pthread_detach");
 485         }
 486
 487 metadata_timer_error:
 488         ret = pthread_join(sessiond_thread, &status);
 489         if (ret != 0) {
 490                 perror("pthread_join");
 491                 goto error;
 492         }
 493
 494 sessiond_error:
 495         ret = pthread_join(data_thread, &status);
 496         if (ret != 0) {
 497                 perror("pthread_join");
 498                 goto error;
 499         }
 500
 501 data_error:
 502         ret = pthread_join(metadata_thread, &status);
 503         if (ret != 0) {
 504                 perror("pthread_join");
 505                 goto error;
 506         }
 507
 508 metadata_error:
 509         ret = pthread_join(channel_thread, &status);
 510         if (ret != 0) {
 511                 perror("pthread_join");
 512                 goto error;
 513         }
 514
 515 channel_error:
 516         ret = pthread_join(health_thread, &status);
 517         if (ret != 0) {
 518                 PERROR("pthread_join health thread");
 519                 goto error;     /* join error, exit without cleanup */
 520         }
 521
 522 health_error:
 523         utils_close_pipe(health_quit_pipe);
 524
 525 error_health_pipe:
 526         if (!ret) {
 527                 ret = EXIT_SUCCESS;
 528                 goto end;
 529         }
 530
 531 error:
 532         ret = EXIT_FAILURE;
 533
 534 end:
 535         tmp_ctx = ctx;
 536         ctx = NULL;
 537         cmm_barrier();  /* Clear ctx for signal handler. */
 538         lttng_consumer_destroy(tmp_ctx);
 539         lttng_consumer_cleanup();
 540         if (health_consumerd) {
 541                 health_app_destroy(health_consumerd);
 542         }
 543
 544         /* Ensure all prior call_rcu are done. */
 545         rcu_barrier();
 546         return ret;
 547 }