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/compat/getenv.h>
  51 #include <common/sessiond-comm/sessiond-comm.h>
  52 #include <common/utils.h>
  53
  54 #include "lttng-consumerd.h"
  55 #include "health-consumerd.h"
  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 catched 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 int parse_args(int argc, char **argv)
 191 {
 192         int c, ret = 0;
 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:",
 213                                 long_options, &option_index);
 214                 if (c == -1) {
 215                         break;
 216                 }
 217
 218                 switch (c) {
 219                 case 0:
 220                         fprintf(stderr, "option %s",
 221                                 long_options[option_index].name);
 222                         if (optarg) {
 223                                 fprintf(stderr, " with arg %s\n", optarg);
 224                                 ret = -1;
 225                                 goto end;
 226                         }
 227                         break;
 228                 case 'c':
 229                         if (lttng_is_setuid_setgid()) {
 230                                 WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 231                                         "-c, --consumerd-cmd-sock");
 232                         } else {
 233                                 snprintf(command_sock_path, PATH_MAX, "%s", optarg);
 234                         }
 235                         break;
 236                 case 'e':
 237                         if (lttng_is_setuid_setgid()) {
 238                                 WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 239                                         "-e, --consumerd-err-sock");
 240                         } else {
 241                                 snprintf(error_sock_path, PATH_MAX, "%s", optarg);
 242                         }
 243                         break;
 244                 case 'd':
 245                         opt_daemon = 1;
 246                         break;
 247                 case 'g':
 248                         if (lttng_is_setuid_setgid()) {
 249                                 WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 250                                         "-g, --group");
 251                         } else {
 252                                 tracing_group_name = optarg;
 253                         }
 254                         break;
 255                 case 'h':
 256                         usage(stdout);
 257                         exit(EXIT_SUCCESS);
 258                 case 'q':
 259                         lttng_opt_quiet = 1;
 260                         break;
 261                 case 'v':
 262                         lttng_opt_verbose = 1;
 263                         break;
 264                 case 'V':
 265                         fprintf(stdout, "%s\n", VERSION);
 266                         exit(EXIT_SUCCESS);
 267                 case 'k':
 268                         opt_type = LTTNG_CONSUMER_KERNEL;
 269                         break;
 270 #ifdef HAVE_LIBLTTNG_UST_CTL
 271                 case 'u':
 272 # if (CAA_BITS_PER_LONG == 64)
 273                         opt_type = LTTNG_CONSUMER64_UST;
 274 # elif (CAA_BITS_PER_LONG == 32)
 275                         opt_type = LTTNG_CONSUMER32_UST;
 276 # else
 277 #  error "Unknown bitness"
 278 # endif
 279                         break;
 280 #endif
 281                 default:
 282                         usage(stderr);
 283                         ret = -1;
 284                         goto end;
 285                 }
 286         }
 287 end:
 288         return ret;
 289 }
 290
 291 /*
 292  * Set open files limit to unlimited. This daemon can open a large number of
 293  * file descriptors in order to consumer multiple kernel traces.
 294  */
 295 static void set_ulimit(void)
 296 {
 297         int ret;
 298         struct rlimit lim;
 299
 300         /* The kernel does not allowed an infinite limit for open files */
 301         lim.rlim_cur = 65535;
 302         lim.rlim_max = 65535;
 303
 304         ret = setrlimit(RLIMIT_NOFILE, &lim);
 305         if (ret < 0) {
 306                 PERROR("failed to set open files limit");
 307         }
 308 }
 309
 310 /*
 311  * main
 312  */
 313 int main(int argc, char **argv)
 314 {
 315         int ret = 0, retval = 0;
 316         void *status;
 317         struct lttng_consumer_local_data *tmp_ctx;
 318
 319         if (set_signal_handler()) {
 320                 retval = -1;
 321                 goto exit_set_signal_handler;
 322         }
 323
 324         /* Parse arguments */
 325         progname = argv[0];
 326         if (parse_args(argc, argv)) {
 327                 retval = -1;
 328                 goto exit_options;
 329         }
 330
 331         /* Daemonize */
 332         if (opt_daemon) {
 333                 int i;
 334
 335                 /*
 336                  * fork
 337                  * child: setsid, close FD 0, 1, 2, chdir /
 338                  * parent: exit (if fork is successful)
 339                  */
 340                 ret = daemon(0, 0);
 341                 if (ret < 0) {
 342                         PERROR("daemon");
 343                         retval = -1;
 344                         goto exit_options;
 345                 }
 346                 /*
 347                  * We are in the child. Make sure all other file
 348                  * descriptors are closed, in case we are called with
 349                  * more opened file descriptors than the standard ones.
 350                  */
 351                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
 352                         (void) close(i);
 353                 }
 354         }
 355
 356         /*
 357          * Starting from here, we can create threads. This needs to be after
 358          * lttng_daemonize due to RCU.
 359          */
 360
 361         health_consumerd = health_app_create(NR_HEALTH_CONSUMERD_TYPES);
 362         if (!health_consumerd) {
 363                 retval = -1;
 364                 goto exit_health_consumerd_cleanup;
 365         }
 366
 367         /* Set up max poll set size */
 368         if (lttng_poll_set_max_size()) {
 369                 retval = -1;
 370                 goto exit_init_data;
 371         }
 372
 373         if (*command_sock_path == '\0') {
 374                 switch (opt_type) {
 375                 case LTTNG_CONSUMER_KERNEL:
 376                         ret = snprintf(command_sock_path, PATH_MAX,
 377                                         DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
 378                                         DEFAULT_LTTNG_RUNDIR);
 379                         if (ret < 0) {
 380                                 retval = -1;
 381                                 goto exit_init_data;
 382                         }
 383                         break;
 384                 case LTTNG_CONSUMER64_UST:
 385                         ret = snprintf(command_sock_path, PATH_MAX,
 386                                         DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
 387                                         DEFAULT_LTTNG_RUNDIR);
 388                         if (ret < 0) {
 389                                 retval = -1;
 390                                 goto exit_init_data;
 391                         }
 392                         break;
 393                 case LTTNG_CONSUMER32_UST:
 394                         ret = snprintf(command_sock_path, PATH_MAX,
 395                                         DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
 396                                         DEFAULT_LTTNG_RUNDIR);
 397                         if (ret < 0) {
 398                                 retval = -1;
 399                                 goto exit_init_data;
 400                         }
 401                         break;
 402                 default:
 403                         ERR("Unknown consumerd type");
 404                         retval = -1;
 405                         goto exit_init_data;
 406                 }
 407         }
 408
 409         /* Init */
 410         if (lttng_consumer_init()) {
 411                 retval = -1;
 412                 goto exit_init_data;
 413         }
 414
 415         /* Initialize communication library */
 416         lttcomm_init();
 417         /* Initialize TCP timeout values */
 418         lttcomm_inet_init();
 419
 420         if (!getuid()) {
 421                 /* Set limit for open files */
 422                 set_ulimit();
 423         }
 424
 425         if (run_as_create_worker(argv[0]) < 0) {
 426                 goto exit_init_data;
 427         }
 428
 429         /* create the consumer instance with and assign the callbacks */
 430         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 431                 NULL, lttng_consumer_on_recv_stream, NULL);
 432         if (!ctx) {
 433                 retval = -1;
 434                 goto exit_init_data;
 435         }
 436
 437         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 438         if (*error_sock_path == '\0') {
 439                 switch (opt_type) {
 440                 case LTTNG_CONSUMER_KERNEL:
 441                         ret = snprintf(error_sock_path, PATH_MAX,
 442                                         DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
 443                                         DEFAULT_LTTNG_RUNDIR);
 444                         if (ret < 0) {
 445                                 retval = -1;
 446                                 goto exit_init_data;
 447                         }
 448                         break;
 449                 case LTTNG_CONSUMER64_UST:
 450                         ret = snprintf(error_sock_path, PATH_MAX,
 451                                         DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
 452                                         DEFAULT_LTTNG_RUNDIR);
 453                         if (ret < 0) {
 454                                 retval = -1;
 455                                 goto exit_init_data;
 456                         }
 457                         break;
 458                 case LTTNG_CONSUMER32_UST:
 459                         ret = snprintf(error_sock_path, PATH_MAX,
 460                                         DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
 461                                         DEFAULT_LTTNG_RUNDIR);
 462                         if (ret < 0) {
 463                                 retval = -1;
 464                                 goto exit_init_data;
 465                         }
 466                         break;
 467                 default:
 468                         ERR("Unknown consumerd type");
 469                         retval = -1;
 470                         goto exit_init_data;
 471                 }
 472         }
 473
 474         /* Connect to the socket created by lttng-sessiond to report errors */
 475         DBG("Connecting to error socket %s", error_sock_path);
 476         ret = lttcomm_connect_unix_sock(error_sock_path);
 477         /*
 478          * Not a fatal error, but all communication with lttng-sessiond will
 479          * fail.
 480          */
 481         if (ret < 0) {
 482                 WARN("Cannot connect to error socket (is lttng-sessiond started?)");
 483         }
 484         lttng_consumer_set_error_sock(ctx, ret);
 485
 486         /*
 487          * Block RT signals used for UST periodical metadata flush and the live
 488          * timer in main, and create a dedicated thread to handle these signals.
 489          */
 490         if (consumer_signal_init()) {
 491                 retval = -1;
 492                 goto exit_init_data;
 493         }
 494
 495         ctx->type = opt_type;
 496
 497         if (utils_create_pipe(health_quit_pipe)) {
 498                 retval = -1;
 499                 goto exit_health_pipe;
 500         }
 501
 502         /* Create thread to manage the client socket */
 503         ret = pthread_create(&health_thread, NULL,
 504                         thread_manage_health, (void *) NULL);
 505         if (ret) {
 506                 errno = ret;
 507                 PERROR("pthread_create health");
 508                 retval = -1;
 509                 goto exit_health_thread;
 510         }
 511
 512         /*
 513          * Wait for health thread to be initialized before letting the
 514          * sessiond thread reply to the sessiond that we are ready.
 515          */
 516         while (uatomic_read(&lttng_consumer_ready)) {
 517                 usleep(100000);
 518         }
 519         cmm_smp_mb();   /* Read ready before following operations */
 520
 521         /* Create thread to manage channels */
 522         ret = pthread_create(&channel_thread, NULL,
 523                         consumer_thread_channel_poll,
 524                         (void *) ctx);
 525         if (ret) {
 526                 errno = ret;
 527                 PERROR("pthread_create");
 528                 retval = -1;
 529                 goto exit_channel_thread;
 530         }
 531
 532         /* Create thread to manage the polling/writing of trace metadata */
 533         ret = pthread_create(&metadata_thread, NULL,
 534                         consumer_thread_metadata_poll,
 535                         (void *) ctx);
 536         if (ret) {
 537                 errno = ret;
 538                 PERROR("pthread_create");
 539                 retval = -1;
 540                 goto exit_metadata_thread;
 541         }
 542
 543         /* Create thread to manage the polling/writing of trace data */
 544         ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
 545                         (void *) ctx);
 546         if (ret) {
 547                 errno = ret;
 548                 PERROR("pthread_create");
 549                 retval = -1;
 550                 goto exit_data_thread;
 551         }
 552
 553         /* Create the thread to manage the receive of fd */
 554         ret = pthread_create(&sessiond_thread, NULL,
 555                         consumer_thread_sessiond_poll,
 556                         (void *) ctx);
 557         if (ret) {
 558                 errno = ret;
 559                 PERROR("pthread_create");
 560                 retval = -1;
 561                 goto exit_sessiond_thread;
 562         }
 563
 564         /*
 565          * Create the thread to manage the UST metadata periodic timer and
 566          * live timer.
 567          */
 568         ret = pthread_create(&metadata_timer_thread, NULL,
 569                         consumer_timer_thread, (void *) ctx);
 570         if (ret) {
 571                 errno = ret;
 572                 PERROR("pthread_create");
 573                 retval = -1;
 574                 goto exit_metadata_timer_thread;
 575         }
 576
 577         ret = pthread_detach(metadata_timer_thread);
 578         if (ret) {
 579                 errno = ret;
 580                 PERROR("pthread_detach");
 581                 retval = -1;
 582                 goto exit_metadata_timer_detach;
 583         }
 584
 585         /*
 586          * This is where we start awaiting program completion (e.g. through
 587          * signal that asks threads to teardown.
 588          */
 589
 590 exit_metadata_timer_detach:
 591 exit_metadata_timer_thread:
 592         ret = pthread_join(sessiond_thread, &status);
 593         if (ret) {
 594                 errno = ret;
 595                 PERROR("pthread_join sessiond_thread");
 596                 retval = -1;
 597         }
 598 exit_sessiond_thread:
 599
 600         ret = pthread_join(data_thread, &status);
 601         if (ret) {
 602                 errno = ret;
 603                 PERROR("pthread_join data_thread");
 604                 retval = -1;
 605         }
 606 exit_data_thread:
 607
 608         ret = pthread_join(metadata_thread, &status);
 609         if (ret) {
 610                 errno = ret;
 611                 PERROR("pthread_join metadata_thread");
 612                 retval = -1;
 613         }
 614 exit_metadata_thread:
 615
 616         ret = pthread_join(channel_thread, &status);
 617         if (ret) {
 618                 errno = ret;
 619                 PERROR("pthread_join channel_thread");
 620                 retval = -1;
 621         }
 622 exit_channel_thread:
 623
 624         ret = pthread_join(health_thread, &status);
 625         if (ret) {
 626                 errno = ret;
 627                 PERROR("pthread_join health_thread");
 628                 retval = -1;
 629         }
 630 exit_health_thread:
 631
 632         utils_close_pipe(health_quit_pipe);
 633 exit_health_pipe:
 634
 635 exit_init_data:
 636         tmp_ctx = ctx;
 637         ctx = NULL;
 638         cmm_barrier();  /* Clear ctx for signal handler. */
 639         lttng_consumer_destroy(tmp_ctx);
 640         lttng_consumer_cleanup();
 641
 642         if (health_consumerd) {
 643                 health_app_destroy(health_consumerd);
 644         }
 645 exit_health_consumerd_cleanup:
 646
 647 exit_options:
 648
 649 exit_set_signal_handler:
 650         /* Ensure all prior call_rcu are done. */
 651         rcu_barrier();
 652
 653         if (!retval) {
 654                 exit(EXIT_SUCCESS);
 655         } else {
 656                 exit(EXIT_FAILURE);
 657         }
 658 }