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         if (ctx) {
 105                 lttng_consumer_should_exit(ctx);
 106         }
 107 }
 108
 109 /*
 110  * Setup signal handler for :
 111  *      SIGINT, SIGTERM, SIGPIPE
 112  */
 113 static int set_signal_handler(void)
 114 {
 115         int ret = 0;
 116         struct sigaction sa;
 117         sigset_t sigset;
 118
 119         if ((ret = sigemptyset(&sigset)) < 0) {
 120                 PERROR("sigemptyset");
 121                 return ret;
 122         }
 123
 124         sa.sa_mask = sigset;
 125         sa.sa_flags = 0;
 126
 127         sa.sa_handler = sighandler;
 128         if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
 129                 PERROR("sigaction");
 130                 return ret;
 131         }
 132
 133         if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) {
 134                 PERROR("sigaction");
 135                 return ret;
 136         }
 137
 138         sa.sa_handler = SIG_IGN;
 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 int parse_args(int argc, char **argv)
 185 {
 186         int c, ret = 0;
 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:",
 207                                 long_options, &option_index);
 208                 if (c == -1) {
 209                         break;
 210                 }
 211
 212                 switch (c) {
 213                 case 0:
 214                         fprintf(stderr, "option %s",
 215                                 long_options[option_index].name);
 216                         if (optarg) {
 217                                 fprintf(stderr, " with arg %s\n", optarg);
 218                                 ret = -1;
 219                                 goto end;
 220                         }
 221                         break;
 222                 case 'c':
 223                         if (lttng_is_setuid_setgid()) {
 224                                 WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 225                                         "-c, --consumerd-cmd-sock");
 226                         } else {
 227                                 snprintf(command_sock_path, PATH_MAX, "%s", optarg);
 228                         }
 229                         break;
 230                 case 'e':
 231                         if (lttng_is_setuid_setgid()) {
 232                                 WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 233                                         "-e, --consumerd-err-sock");
 234                         } else {
 235                                 snprintf(error_sock_path, PATH_MAX, "%s", optarg);
 236                         }
 237                         break;
 238                 case 'd':
 239                         opt_daemon = 1;
 240                         break;
 241                 case 'g':
 242                         if (lttng_is_setuid_setgid()) {
 243                                 WARN("Getting '%s' argument from setuid/setgid binary refused for security reasons.",
 244                                         "-g, --group");
 245                         } else {
 246                                 tracing_group_name = optarg;
 247                         }
 248                         break;
 249                 case 'h':
 250                         usage(stdout);
 251                         exit(EXIT_SUCCESS);
 252                 case 'q':
 253                         lttng_opt_quiet = 1;
 254                         break;
 255                 case 'v':
 256                         lttng_opt_verbose = 1;
 257                         break;
 258                 case 'V':
 259                         fprintf(stdout, "%s\n", VERSION);
 260                         exit(EXIT_SUCCESS);
 261                 case 'k':
 262                         opt_type = LTTNG_CONSUMER_KERNEL;
 263                         break;
 264 #ifdef HAVE_LIBLTTNG_UST_CTL
 265                 case 'u':
 266 # if (CAA_BITS_PER_LONG == 64)
 267                         opt_type = LTTNG_CONSUMER64_UST;
 268 # elif (CAA_BITS_PER_LONG == 32)
 269                         opt_type = LTTNG_CONSUMER32_UST;
 270 # else
 271 #  error "Unknown bitness"
 272 # endif
 273                         break;
 274 #endif
 275                 default:
 276                         usage(stderr);
 277                         ret = -1;
 278                         goto end;
 279                 }
 280         }
 281 end:
 282         return ret;
 283 }
 284
 285 /*
 286  * Set open files limit to unlimited. This daemon can open a large number of
 287  * file descriptors in order to consumer multiple kernel traces.
 288  */
 289 static void set_ulimit(void)
 290 {
 291         int ret;
 292         struct rlimit lim;
 293
 294         /* The kernel does not allowed an infinite limit for open files */
 295         lim.rlim_cur = 65535;
 296         lim.rlim_max = 65535;
 297
 298         ret = setrlimit(RLIMIT_NOFILE, &lim);
 299         if (ret < 0) {
 300                 PERROR("failed to set open files limit");
 301         }
 302 }
 303
 304 /*
 305  * main
 306  */
 307 int main(int argc, char **argv)
 308 {
 309         int ret = 0, retval = 0;
 310         void *status;
 311         struct lttng_consumer_local_data *tmp_ctx;
 312
 313         if (set_signal_handler()) {
 314                 retval = -1;
 315                 goto exit_set_signal_handler;
 316         }
 317
 318         /* Parse arguments */
 319         progname = argv[0];
 320         if (parse_args(argc, argv)) {
 321                 retval = -1;
 322                 goto exit_options;
 323         }
 324
 325         /* Daemonize */
 326         if (opt_daemon) {
 327                 int i;
 328
 329                 /*
 330                  * fork
 331                  * child: setsid, close FD 0, 1, 2, chdir /
 332                  * parent: exit (if fork is successful)
 333                  */
 334                 ret = daemon(0, 0);
 335                 if (ret < 0) {
 336                         PERROR("daemon");
 337                         retval = -1;
 338                         goto exit_options;
 339                 }
 340                 /*
 341                  * We are in the child. Make sure all other file
 342                  * descriptors are closed, in case we are called with
 343                  * more opened file descriptors than the standard ones.
 344                  */
 345                 for (i = 3; i < sysconf(_SC_OPEN_MAX); i++) {
 346                         (void) close(i);
 347                 }
 348         }
 349
 350         /*
 351          * Starting from here, we can create threads. This needs to be after
 352          * lttng_daemonize due to RCU.
 353          */
 354
 355         health_consumerd = health_app_create(NR_HEALTH_CONSUMERD_TYPES);
 356         if (!health_consumerd) {
 357                 retval = -1;
 358                 goto exit_health_consumerd_cleanup;
 359         }
 360
 361         /* Set up max poll set size */
 362         if (lttng_poll_set_max_size()) {
 363                 retval = -1;
 364                 goto exit_init_data;
 365         }
 366
 367         if (*command_sock_path == '\0') {
 368                 switch (opt_type) {
 369                 case LTTNG_CONSUMER_KERNEL:
 370                         ret = snprintf(command_sock_path, PATH_MAX,
 371                                         DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
 372                                         DEFAULT_LTTNG_RUNDIR);
 373                         if (ret < 0) {
 374                                 retval = -1;
 375                                 goto exit_init_data;
 376                         }
 377                         break;
 378                 case LTTNG_CONSUMER64_UST:
 379                         ret = snprintf(command_sock_path, PATH_MAX,
 380                                         DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
 381                                         DEFAULT_LTTNG_RUNDIR);
 382                         if (ret < 0) {
 383                                 retval = -1;
 384                                 goto exit_init_data;
 385                         }
 386                         break;
 387                 case LTTNG_CONSUMER32_UST:
 388                         ret = snprintf(command_sock_path, PATH_MAX,
 389                                         DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
 390                                         DEFAULT_LTTNG_RUNDIR);
 391                         if (ret < 0) {
 392                                 retval = -1;
 393                                 goto exit_init_data;
 394                         }
 395                         break;
 396                 default:
 397                         ERR("Unknown consumerd type");
 398                         retval = -1;
 399                         goto exit_init_data;
 400                 }
 401         }
 402
 403         /* Init */
 404         if (lttng_consumer_init()) {
 405                 retval = -1;
 406                 goto exit_init_data;
 407         }
 408
 409         /* Initialize communication library */
 410         lttcomm_init();
 411         /* Initialize TCP timeout values */
 412         lttcomm_inet_init();
 413
 414         if (!getuid()) {
 415                 /* Set limit for open files */
 416                 set_ulimit();
 417         }
 418
 419         if (run_as_create_worker(argv[0]) < 0) {
 420                 goto exit_init_data;
 421         }
 422
 423         /* create the consumer instance with and assign the callbacks */
 424         ctx = lttng_consumer_create(opt_type, lttng_consumer_read_subbuffer,
 425                 NULL, lttng_consumer_on_recv_stream, NULL);
 426         if (!ctx) {
 427                 retval = -1;
 428                 goto exit_init_data;
 429         }
 430
 431         lttng_consumer_set_command_sock_path(ctx, command_sock_path);
 432         if (*error_sock_path == '\0') {
 433                 switch (opt_type) {
 434                 case LTTNG_CONSUMER_KERNEL:
 435                         ret = snprintf(error_sock_path, PATH_MAX,
 436                                         DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
 437                                         DEFAULT_LTTNG_RUNDIR);
 438                         if (ret < 0) {
 439                                 retval = -1;
 440                                 goto exit_init_data;
 441                         }
 442                         break;
 443                 case LTTNG_CONSUMER64_UST:
 444                         ret = snprintf(error_sock_path, PATH_MAX,
 445                                         DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
 446                                         DEFAULT_LTTNG_RUNDIR);
 447                         if (ret < 0) {
 448                                 retval = -1;
 449                                 goto exit_init_data;
 450                         }
 451                         break;
 452                 case LTTNG_CONSUMER32_UST:
 453                         ret = snprintf(error_sock_path, PATH_MAX,
 454                                         DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
 455                                         DEFAULT_LTTNG_RUNDIR);
 456                         if (ret < 0) {
 457                                 retval = -1;
 458                                 goto exit_init_data;
 459                         }
 460                         break;
 461                 default:
 462                         ERR("Unknown consumerd type");
 463                         retval = -1;
 464                         goto exit_init_data;
 465                 }
 466         }
 467
 468         /* Connect to the socket created by lttng-sessiond to report errors */
 469         DBG("Connecting to error socket %s", error_sock_path);
 470         ret = lttcomm_connect_unix_sock(error_sock_path);
 471         /*
 472          * Not a fatal error, but all communication with lttng-sessiond will
 473          * fail.
 474          */
 475         if (ret < 0) {
 476                 WARN("Cannot connect to error socket (is lttng-sessiond started?)");
 477         }
 478         lttng_consumer_set_error_sock(ctx, ret);
 479
 480         /*
 481          * Block RT signals used for UST periodical metadata flush and the live
 482          * timer in main, and create a dedicated thread to handle these signals.
 483          */
 484         if (consumer_signal_init()) {
 485                 retval = -1;
 486                 goto exit_init_data;
 487         }
 488
 489         ctx->type = opt_type;
 490
 491         if (utils_create_pipe(health_quit_pipe)) {
 492                 retval = -1;
 493                 goto exit_health_pipe;
 494         }
 495
 496         /* Create thread to manage the client socket */
 497         ret = pthread_create(&health_thread, NULL,
 498                         thread_manage_health, (void *) NULL);
 499         if (ret) {
 500                 errno = ret;
 501                 PERROR("pthread_create health");
 502                 retval = -1;
 503                 goto exit_health_thread;
 504         }
 505
 506         /*
 507          * Wait for health thread to be initialized before letting the
 508          * sessiond thread reply to the sessiond that we are ready.
 509          */
 510         while (uatomic_read(&lttng_consumer_ready)) {
 511                 usleep(100000);
 512         }
 513         cmm_smp_mb();   /* Read ready before following operations */
 514
 515         /* Create thread to manage channels */
 516         ret = pthread_create(&channel_thread, NULL,
 517                         consumer_thread_channel_poll,
 518                         (void *) ctx);
 519         if (ret) {
 520                 errno = ret;
 521                 PERROR("pthread_create");
 522                 retval = -1;
 523                 goto exit_channel_thread;
 524         }
 525
 526         /* Create thread to manage the polling/writing of trace metadata */
 527         ret = pthread_create(&metadata_thread, NULL,
 528                         consumer_thread_metadata_poll,
 529                         (void *) ctx);
 530         if (ret) {
 531                 errno = ret;
 532                 PERROR("pthread_create");
 533                 retval = -1;
 534                 goto exit_metadata_thread;
 535         }
 536
 537         /* Create thread to manage the polling/writing of trace data */
 538         ret = pthread_create(&data_thread, NULL, consumer_thread_data_poll,
 539                         (void *) ctx);
 540         if (ret) {
 541                 errno = ret;
 542                 PERROR("pthread_create");
 543                 retval = -1;
 544                 goto exit_data_thread;
 545         }
 546
 547         /* Create the thread to manage the receive of fd */
 548         ret = pthread_create(&sessiond_thread, NULL,
 549                         consumer_thread_sessiond_poll,
 550                         (void *) ctx);
 551         if (ret) {
 552                 errno = ret;
 553                 PERROR("pthread_create");
 554                 retval = -1;
 555                 goto exit_sessiond_thread;
 556         }
 557
 558         /*
 559          * Create the thread to manage the UST metadata periodic timer and
 560          * live timer.
 561          */
 562         ret = pthread_create(&metadata_timer_thread, NULL,
 563                         consumer_timer_thread, (void *) ctx);
 564         if (ret) {
 565                 errno = ret;
 566                 PERROR("pthread_create");
 567                 retval = -1;
 568                 goto exit_metadata_timer_thread;
 569         }
 570
 571         ret = pthread_detach(metadata_timer_thread);
 572         if (ret) {
 573                 errno = ret;
 574                 PERROR("pthread_detach");
 575                 retval = -1;
 576                 goto exit_metadata_timer_detach;
 577         }
 578
 579         /*
 580          * This is where we start awaiting program completion (e.g. through
 581          * signal that asks threads to teardown.
 582          */
 583
 584 exit_metadata_timer_detach:
 585 exit_metadata_timer_thread:
 586         ret = pthread_join(sessiond_thread, &status);
 587         if (ret) {
 588                 errno = ret;
 589                 PERROR("pthread_join sessiond_thread");
 590                 retval = -1;
 591         }
 592 exit_sessiond_thread:
 593
 594         ret = pthread_join(data_thread, &status);
 595         if (ret) {
 596                 errno = ret;
 597                 PERROR("pthread_join data_thread");
 598                 retval = -1;
 599         }
 600 exit_data_thread:
 601
 602         ret = pthread_join(metadata_thread, &status);
 603         if (ret) {
 604                 errno = ret;
 605                 PERROR("pthread_join metadata_thread");
 606                 retval = -1;
 607         }
 608 exit_metadata_thread:
 609
 610         ret = pthread_join(channel_thread, &status);
 611         if (ret) {
 612                 errno = ret;
 613                 PERROR("pthread_join channel_thread");
 614                 retval = -1;
 615         }
 616 exit_channel_thread:
 617
 618         ret = pthread_join(health_thread, &status);
 619         if (ret) {
 620                 errno = ret;
 621                 PERROR("pthread_join health_thread");
 622                 retval = -1;
 623         }
 624 exit_health_thread:
 625
 626         utils_close_pipe(health_quit_pipe);
 627 exit_health_pipe:
 628
 629 exit_init_data:
 630         tmp_ctx = ctx;
 631         ctx = NULL;
 632         cmm_barrier();  /* Clear ctx for signal handler. */
 633         lttng_consumer_destroy(tmp_ctx);
 634         lttng_consumer_cleanup();
 635
 636         if (health_consumerd) {
 637                 health_app_destroy(health_consumerd);
 638         }
 639         /* Ensure all prior call_rcu are done. */
 640         rcu_barrier();
 641
 642         run_as_destroy_worker();
 643
 644 exit_health_consumerd_cleanup:
 645 exit_options:
 646 exit_set_signal_handler:
 647
 648         if (!retval) {
 649                 exit(EXIT_SUCCESS);
 650         } else {
 651                 exit(EXIT_FAILURE);
 652         }
 653 }