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