src/lttngtop.c

   1 /*
   2  * Copyright (C) 2011 Julien Desfossez
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License Version 2 as
   6  * published by the Free Software Foundation;
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #define _GNU_SOURCE
  19 #include <config.h>
  20 #include <stdio.h>
  21 #include <stdint.h>
  22 #include <babeltrace/babeltrace.h>
  23 #include <babeltrace/ctf/events.h>
  24 #include <babeltrace/ctf/callbacks.h>
  25 #include <babeltrace/ctf/iterator.h>
  26 #include <fcntl.h>
  27 #include <pthread.h>
  28 #include <popt.h>
  29 #include <stdlib.h>
  30 #include <ftw.h>
  31 #include <dirent.h>
  32 #include <ctype.h>
  33 #include <sys/stat.h>
  34 #include <unistd.h>
  35 #include <string.h>
  36 #include <errno.h>
  37 #include <sys/types.h>
  38 #include <fts.h>
  39 #include <assert.h>
  40
  41 #include "lttngtoptypes.h"
  42 #include "cputop.h"
  43 #include "iostreamtop.h"
  44 #include "cursesdisplay.h"
  45 #include "common.h"
  46
  47 #define DEFAULT_FILE_ARRAY_SIZE 1
  48
  49 const char *opt_input_path;
  50
  51 struct lttngtop *copy;
  52 pthread_t display_thread;
  53 pthread_t timer_thread;
  54
  55 unsigned long refresh_display = 1 * NSEC_PER_SEC;
  56 unsigned long last_display_update = 0;
  57 int quit = 0;
  58
  59 enum {
  60         OPT_NONE = 0,
  61         OPT_HELP,
  62         OPT_LIST,
  63         OPT_VERBOSE,
  64         OPT_DEBUG,
  65         OPT_NAMES,
  66 };
  67
  68 static struct poptOption long_options[] = {
  69         /* longName, shortName, argInfo, argPtr, value, descrip, argDesc */
  70         { "help", 'h', POPT_ARG_NONE, NULL, OPT_HELP, NULL, NULL },
  71         { NULL, 0, 0, NULL, 0, NULL, NULL },
  72 };
  73
  74 void *refresh_thread(void *p)
  75 {
  76         while (1) {
  77                 if (quit)
  78                         return NULL;
  79                 sem_wait(&pause_sem);
  80                 sem_post(&pause_sem);
  81                 sem_post(&timer);
  82                 sleep(refresh_display/NSEC_PER_SEC);
  83         }
  84 }
  85
  86 void *ncurses_display(void *p)
  87 {
  88         unsigned int current_display_index = 0;
  89
  90         sem_wait(&bootstrap);
  91         init_ncurses();
  92
  93         while (1) {
  94                 sem_wait(&timer);
  95                 sem_wait(&goodtodisplay);
  96                 sem_wait(&pause_sem);
  97
  98                 copy = g_ptr_array_index(copies, current_display_index);
  99                 assert(copy);
 100                 display(current_display_index++);
 101
 102                 sem_post(&goodtoupdate);
 103                 sem_post(&pause_sem);
 104
 105                 if (quit) {
 106                         reset_ncurses();
 107                         pthread_exit(0);
 108                 }
 109         }
 110 }
 111
 112 /*
 113  * hook on each event to check the timestamp and refresh the display if
 114  * necessary
 115  */
 116 enum bt_cb_ret check_timestamp(struct bt_ctf_event *call_data, void *private_data)
 117 {
 118         unsigned long timestamp;
 119
 120         timestamp = bt_ctf_get_timestamp(call_data);
 121         if (timestamp == -1ULL)
 122                 goto error;
 123
 124         if (last_display_update == 0)
 125                 last_display_update = timestamp;
 126
 127         if (timestamp - last_display_update >= refresh_display) {
 128                 sem_wait(&goodtoupdate);
 129                 g_ptr_array_add(copies, get_copy_lttngtop(last_display_update,
 130                                         timestamp));
 131                 sem_post(&goodtodisplay);
 132                 sem_post(&bootstrap);
 133                 last_display_update = timestamp;
 134         }
 135         return BT_CB_OK;
 136
 137 error:
 138         fprintf(stderr, "check_timestamp callback error\n");
 139         return BT_CB_ERROR_STOP;
 140 }
 141
 142 /*
 143  * get_perf_counter : get or create and return a perf_counter struct for
 144  * either a process or a cpu (only one of the 2 parameters mandatory)
 145  */
 146 struct perfcounter *get_perf_counter(const char *name, struct processtop *proc,
 147                 struct cputime *cpu)
 148 {
 149         struct perfcounter *ret, *global;
 150         GHashTable *table;
 151
 152         if (proc)
 153                 table = proc->perf;
 154         else if (cpu)
 155                 table = cpu->perf;
 156         else
 157                 goto error;
 158
 159         ret = g_hash_table_lookup(table, (gpointer) name);
 160         if (ret)
 161                 goto end;
 162
 163         ret = g_new0(struct perfcounter, 1);
 164         /* by default, make it visible in the UI */
 165         ret->visible = 1;
 166         g_hash_table_insert(table, (gpointer) strdup(name), ret);
 167
 168         global = g_hash_table_lookup(global_perf_liszt, (gpointer) name);
 169         if (!global) {
 170                 global = g_new0(struct perfcounter, 1);
 171                 memcpy(global, ret, sizeof(struct perfcounter));
 172                 /* by default, sort on the first perf context */
 173                 if (g_hash_table_size(global_perf_liszt) == 0)
 174                         global->sort = 1;
 175                 g_hash_table_insert(global_perf_liszt, (gpointer) strdup(name), global);
 176         }
 177
 178 end:
 179         return ret;
 180
 181 error:
 182         return NULL;
 183 }
 184
 185 void update_perf_value(struct processtop *proc, struct cputime *cpu,
 186                 const char *name, int value)
 187 {
 188         struct perfcounter *cpu_perf, *process_perf;
 189
 190         cpu_perf = get_perf_counter(name, NULL, cpu);
 191         if (cpu_perf->count < value) {
 192                 process_perf = get_perf_counter(name, proc, NULL);
 193                 process_perf->count += value - cpu_perf->count;
 194                 cpu_perf->count = value;
 195         }
 196 }
 197
 198 void extract_perf_counter_scope(const struct bt_ctf_event *event,
 199                 const struct definition *scope,
 200                 struct processtop *proc,
 201                 struct cputime *cpu)
 202 {
 203         struct definition const * const *list = NULL;
 204         unsigned int count;
 205         int i, ret;
 206
 207         if (!scope)
 208                 goto end;
 209
 210         ret = bt_ctf_get_field_list(event, scope, &list, &count);
 211         if (ret < 0)
 212                 goto end;
 213
 214         for (i = 0; i < count; i++) {
 215                 const char *name = bt_ctf_field_name(list[i]);
 216                 if (strncmp(name, "perf_", 5) == 0) {
 217                         int value = bt_ctf_get_uint64(list[i]);
 218                         if (bt_ctf_field_get_error())
 219                                 continue;
 220                         update_perf_value(proc, cpu, name, value);
 221                 }
 222         }
 223
 224 end:
 225         return;
 226 }
 227
 228 void update_perf_counter(struct processtop *proc, const struct bt_ctf_event *event)
 229 {
 230         struct cputime *cpu;
 231         const struct definition *scope;
 232
 233         cpu = get_cpu(get_cpu_id(event));
 234
 235         scope = bt_ctf_get_top_level_scope(event, BT_STREAM_EVENT_CONTEXT);
 236         extract_perf_counter_scope(event, scope, proc, cpu);
 237
 238         scope = bt_ctf_get_top_level_scope(event, BT_STREAM_PACKET_CONTEXT);
 239         extract_perf_counter_scope(event, scope, proc, cpu);
 240
 241         scope = bt_ctf_get_top_level_scope(event, BT_EVENT_CONTEXT);
 242         extract_perf_counter_scope(event, scope, proc, cpu);
 243 }
 244
 245 enum bt_cb_ret fix_process_table(struct bt_ctf_event *call_data,
 246                 void *private_data)
 247 {
 248         int pid, tid, ppid;
 249         char *comm;
 250         struct processtop *parent, *child;
 251         unsigned long timestamp;
 252
 253         /* FIXME : display nice error when missing context pid, tid, ppid and comm */
 254
 255         timestamp = bt_ctf_get_timestamp(call_data);
 256         if (timestamp == -1ULL)
 257                 goto error;
 258
 259         pid = get_context_pid(call_data);
 260         if (pid == -1ULL) {
 261 //              fprintf(stderr, "Missing pid context info\n");
 262                 goto error;
 263         }
 264         tid = get_context_tid(call_data);
 265         if (tid == -1ULL) {
 266 //              fprintf(stderr, "Missing tid context info\n");
 267                 goto error;
 268         }
 269         ppid = get_context_ppid(call_data);
 270         if (ppid == -1ULL) {
 271 //              fprintf(stderr, "Missing ppid context info\n");
 272                 goto error;
 273         }
 274         comm = get_context_comm(call_data);
 275         if (!comm) {
 276 //              fprintf(stderr, "Missing procname context info\n");
 277                 goto error;
 278         }
 279
 280         /* find or create the current process */
 281         child = find_process_tid(&lttngtop, tid, comm);
 282         if (!child)
 283                 child = add_proc(&lttngtop, tid, comm, timestamp);
 284         update_proc(child, pid, tid, ppid, comm);
 285
 286         if (pid != tid) {
 287                 /* find or create the parent */
 288                 parent = find_process_tid(&lttngtop, pid, comm);
 289                 if (!parent) {
 290                         parent = add_proc(&lttngtop, pid, comm, timestamp);
 291                         parent->pid = pid;
 292                 }
 293
 294                 /* attach the parent to the current process */
 295                 child->threadparent = parent;
 296                 add_thread(parent, child);
 297         }
 298
 299         update_perf_counter(child, call_data);
 300
 301         return BT_CB_OK;
 302
 303 error:
 304         return BT_CB_ERROR_STOP;
 305 }
 306
 307 void init_lttngtop()
 308 {
 309         copies = g_ptr_array_new();
 310         global_perf_liszt = g_hash_table_new(g_str_hash, g_str_equal);
 311
 312         sem_init(&goodtodisplay, 0, 0);
 313         sem_init(&goodtoupdate, 0, 1);
 314         sem_init(&timer, 0, 1);
 315         sem_init(&bootstrap, 0, 0);
 316         sem_init(&pause_sem, 0, 1);
 317         sem_init(&end_trace_sem, 0, 0);
 318
 319         reset_global_counters();
 320         lttngtop.nbproc = 0;
 321         lttngtop.nbthreads = 0;
 322         lttngtop.nbfiles = 0;
 323
 324         lttngtop.process_table = g_ptr_array_new();
 325         lttngtop.files_table = g_ptr_array_new();
 326         lttngtop.cpu_table = g_ptr_array_new();
 327 }
 328
 329 void usage(FILE *fp)
 330 {
 331         fprintf(fp, "LTTngTop %s\n\n", VERSION);
 332         fprintf(fp, "Usage : lttngtop /path/to/trace\n");
 333 }
 334
 335 /*
 336  * Return 0 if caller should continue, < 0 if caller should return
 337  * error, > 0 if caller should exit without reporting error.
 338  */
 339 static int parse_options(int argc, char **argv)
 340 {
 341         poptContext pc;
 342         int opt, ret = 0;
 343
 344         if (argc == 1) {
 345                 usage(stdout);
 346                 return 1;   /* exit cleanly */
 347         }
 348
 349         pc = poptGetContext(NULL, argc, (const char **) argv, long_options, 0);
 350         poptReadDefaultConfig(pc, 0);
 351
 352         while ((opt = poptGetNextOpt(pc)) != -1) {
 353                 switch (opt) {
 354                         case OPT_HELP:
 355                                 usage(stdout);
 356                                 ret = 1;    /* exit cleanly */
 357                                 goto end;
 358                         case OPT_LIST:
 359                         //      list_formats(stdout);
 360                                 ret = 1;
 361                                 goto end;
 362                         case OPT_VERBOSE:
 363 //                              babeltrace_verbose = 1;
 364                                 break;
 365                         case OPT_DEBUG:
 366 //                              babeltrace_debug = 1;
 367                                 break;
 368                         case OPT_NAMES:
 369 //                              opt_field_names = 1;
 370                                 break;
 371                         default:
 372                                 ret = -EINVAL;
 373                                 goto end;
 374                 }
 375         }
 376
 377         opt_input_path = poptGetArg(pc);
 378         if (!opt_input_path) {
 379                 ret = -EINVAL;
 380                 goto end;
 381         }
 382 end:
 383         if (pc) {
 384                 poptFreeContext(pc);
 385         }
 386         return ret;
 387 }
 388
 389 void iter_trace(struct bt_context *bt_ctx)
 390 {
 391         struct bt_ctf_iter *iter;
 392         struct bt_iter_pos begin_pos;
 393         const struct bt_ctf_event *event;
 394         int ret = 0;
 395
 396         begin_pos.type = BT_SEEK_BEGIN;
 397         iter = bt_ctf_iter_create(bt_ctx, &begin_pos, NULL);
 398
 399         /* at each event check if we need to refresh */
 400         bt_ctf_iter_add_callback(iter, 0, NULL, 0,
 401                         check_timestamp,
 402                         NULL, NULL, NULL);
 403         /* at each event, verify the status of the process table */
 404         bt_ctf_iter_add_callback(iter, 0, NULL, 0,
 405                         fix_process_table,
 406                         NULL, NULL, NULL);
 407         /* to handle the scheduling events */
 408         bt_ctf_iter_add_callback(iter,
 409                         g_quark_from_static_string("sched_switch"),
 410                         NULL, 0, handle_sched_switch, NULL, NULL, NULL);
 411         /* to clean up the process table */
 412         bt_ctf_iter_add_callback(iter,
 413                         g_quark_from_static_string("sched_process_free"),
 414                         NULL, 0, handle_sched_process_free, NULL, NULL, NULL);
 415         /* to get all the process from the statedumps */
 416         bt_ctf_iter_add_callback(iter,
 417                         g_quark_from_static_string(
 418                                 "lttng_statedump_process_state"),
 419                         NULL, 0, handle_statedump_process_state,
 420                         NULL, NULL, NULL);
 421
 422         /* for IO top */
 423         bt_ctf_iter_add_callback(iter,
 424                         g_quark_from_static_string("exit_syscall"),
 425                         NULL, 0, handle_exit_syscall, NULL, NULL, NULL);
 426         bt_ctf_iter_add_callback(iter,
 427                         g_quark_from_static_string("sys_write"),
 428                         NULL, 0, handle_sys_write, NULL, NULL, NULL);
 429         bt_ctf_iter_add_callback(iter,
 430                         g_quark_from_static_string("sys_read"),
 431                         NULL, 0, handle_sys_read, NULL, NULL, NULL);
 432         bt_ctf_iter_add_callback(iter,
 433                         g_quark_from_static_string("sys_open"),
 434                         NULL, 0, handle_sys_open, NULL, NULL, NULL);
 435         bt_ctf_iter_add_callback(iter,
 436                         g_quark_from_static_string("sys_close"),
 437                         NULL, 0, handle_sys_close, NULL, NULL, NULL);
 438         bt_ctf_iter_add_callback(iter,
 439                         g_quark_from_static_string(
 440                                         "lttng_statedump_file_descriptor"),
 441                         NULL, 0, handle_statedump_file_descriptor,
 442                         NULL, NULL, NULL);
 443
 444         while ((event = bt_ctf_iter_read_event(iter)) != NULL) {
 445                 ret = bt_iter_next(bt_ctf_get_iter(iter));
 446                 if (ret < 0)
 447                         goto end_iter;
 448         }
 449
 450         /* block until quit, we reached the end of the trace */
 451         sem_wait(&end_trace_sem);
 452
 453 end_iter:
 454         bt_ctf_iter_destroy(iter);
 455 }
 456
 457 /*
 458  * bt_context_add_traces_recursive: Open a trace recursively
 459  * (copied from BSD code in converter/babeltrace.c)
 460  *
 461  * Find each trace present in the subdirectory starting from the given
 462  * path, and add them to the context. The packet_seek parameter can be
 463  * NULL: this specify to use the default format packet_seek.
 464  *
 465  * Return: 0 on success, nonzero on failure.
 466  * Unable to open toplevel: failure.
 467  * Unable to open some subdirectory or file: warn and continue;
 468  */
 469 int bt_context_add_traces_recursive(struct bt_context *ctx, const char *path,
 470                 const char *format_str,
 471                 void (*packet_seek)(struct stream_pos *pos,
 472                         size_t offset, int whence))
 473 {
 474         FTS *tree;
 475         FTSENT *node;
 476         GArray *trace_ids;
 477         char lpath[PATH_MAX];
 478         char * const paths[2] = { lpath, NULL };
 479         int ret = -1;
 480
 481         /*
 482          * Need to copy path, because fts_open can change it.
 483          * It is the pointer array, not the strings, that are constant.
 484          */
 485         strncpy(lpath, path, PATH_MAX);
 486         lpath[PATH_MAX - 1] = '\0';
 487
 488         tree = fts_open(paths, FTS_NOCHDIR | FTS_LOGICAL, 0);
 489         if (tree == NULL) {
 490                 fprintf(stderr, "[error] [Context] Cannot traverse \"%s\" for reading.\n",
 491                                 path);
 492                 return -EINVAL;
 493         }
 494
 495         trace_ids = g_array_new(FALSE, TRUE, sizeof(int));
 496
 497         while ((node = fts_read(tree))) {
 498                 int dirfd, metafd;
 499
 500                 if (!(node->fts_info & FTS_D))
 501                         continue;
 502
 503                 dirfd = open(node->fts_accpath, 0);
 504                 if (dirfd < 0) {
 505                         fprintf(stderr, "[error] [Context] Unable to open trace "
 506                                 "directory file descriptor.\n");
 507                         ret = dirfd;
 508                         goto error;
 509                 }
 510                 metafd = openat(dirfd, "metadata", O_RDONLY);
 511                 if (metafd < 0) {
 512                         ret = close(dirfd);
 513                         if (ret < 0) {
 514                                 perror("close");
 515                                 goto error;
 516                         }
 517                 } else {
 518                         int trace_id;
 519
 520                         ret = close(metafd);
 521                         if (ret < 0) {
 522                                 perror("close");
 523                                 goto error;
 524                         }
 525                         ret = close(dirfd);
 526                         if (ret < 0) {
 527                                 perror("close");
 528                                 goto error;
 529                         }
 530
 531                         trace_id = bt_context_add_trace(ctx,
 532                                 node->fts_accpath, format_str,
 533                                 packet_seek, NULL, NULL);
 534                         if (trace_id < 0) {
 535                                 fprintf(stderr, "[warning] [Context] opening trace \"%s\" from %s "
 536                                         "for reading.\n", node->fts_accpath, path);
 537                                 /* Allow to skip erroneous traces. */
 538                                 continue;
 539                         }
 540                         g_array_append_val(trace_ids, trace_id);
 541                 }
 542         }
 543
 544         g_array_free(trace_ids, TRUE);
 545         return ret;
 546
 547 error:
 548         return ret;
 549 }
 550
 551 static int check_field_requirements(const struct bt_ctf_field_decl *const * field_list,
 552                 int field_cnt, int *tid_check, int *pid_check,
 553                 int *procname_check, int *ppid_check)
 554 {
 555         int j;
 556
 557         for (j = 0; j < field_cnt; j++) {
 558                 if (*tid_check == 0) {
 559                         if (strncmp(bt_ctf_get_decl_field_name(field_list[j]), "tid", 3) == 0) {
 560                                 (*tid_check)++;
 561                         }
 562                 }
 563                 if (*pid_check == 0) {
 564                         if (strncmp(bt_ctf_get_decl_field_name(field_list[j]), "pid", 3) == 0)
 565                                 (*pid_check)++;
 566                 }
 567                 if (*ppid_check == 0) {
 568                         if (strncmp(bt_ctf_get_decl_field_name(field_list[j]), "ppid", 4) == 0)
 569                                 (*ppid_check)++;
 570                 }
 571                 if (*procname_check == 0) {
 572                         if (strncmp(bt_ctf_get_decl_field_name(field_list[j]), "procname", 8) == 0)
 573                                 (*procname_check)++;
 574                 }
 575         }
 576         /* if all checks are OK, no need to continue the checks */
 577         if (*tid_check == 1 && *pid_check == 1 && *ppid_check == 1 &&
 578                         *procname_check == 1)
 579                 return 0;
 580
 581         return -1;
 582 }
 583
 584 /*
 585  * check_requirements: check if the required context informations are available
 586  *
 587  * If each mandatory context information is available for at least in one
 588  * event, return 0 otherwise return -1.
 589  */
 590 int check_requirements(struct bt_context *ctx)
 591 {
 592         unsigned int i, evt_cnt, field_cnt;
 593         struct bt_ctf_event_decl *const * evt_list;
 594         const struct bt_ctf_field_decl *const * field_list;
 595         int tid_check = 0;
 596         int pid_check = 0;
 597         int procname_check = 0;
 598         int ppid_check = 0;
 599         int ret = 0;
 600
 601         bt_ctf_get_event_decl_list(0, ctx, &evt_list, &evt_cnt);
 602         for (i = 0; i < evt_cnt; i++) {
 603                 bt_ctf_get_decl_fields(evt_list[i], BT_STREAM_EVENT_CONTEXT,
 604                                 &field_list, &field_cnt);
 605                 ret = check_field_requirements(field_list, field_cnt,
 606                                 &tid_check, &pid_check, &procname_check,
 607                                 &ppid_check);
 608                 if (ret == 0)
 609                         goto end;
 610
 611                 bt_ctf_get_decl_fields(evt_list[i], BT_EVENT_CONTEXT,
 612                                 &field_list, &field_cnt);
 613                 ret = check_field_requirements(field_list, field_cnt,
 614                                 &tid_check, &pid_check, &procname_check,
 615                                 &ppid_check);
 616                 if (ret == 0)
 617                         goto end;
 618
 619                 bt_ctf_get_decl_fields(evt_list[i], BT_STREAM_PACKET_CONTEXT,
 620                                 &field_list, &field_cnt);
 621                 ret = check_field_requirements(field_list, field_cnt,
 622                                 &tid_check, &pid_check, &procname_check,
 623                                 &ppid_check);
 624                 if (ret == 0)
 625                         goto end;
 626         }
 627
 628         if (tid_check == 0) {
 629                 ret = -1;
 630                 fprintf(stderr, "[error] missing tid context information\n");
 631         }
 632         if (pid_check == 0) {
 633                 ret = -1;
 634                 fprintf(stderr, "[error] missing pid context information\n");
 635         }
 636         if (ppid_check == 0) {
 637                 ret = -1;
 638                 fprintf(stderr, "[error] missing ppid context information\n");
 639         }
 640         if (procname_check == 0) {
 641                 ret = -1;
 642                 fprintf(stderr, "[error] missing procname context information\n");
 643         }
 644
 645 end:
 646         return ret;
 647 }
 648
 649 int main(int argc, char **argv)
 650 {
 651         int ret;
 652         struct bt_context *bt_ctx = NULL;
 653
 654         ret = parse_options(argc, argv);
 655         if (ret < 0) {
 656                 fprintf(stdout, "Error parsing options.\n\n");
 657                 usage(stdout);
 658                 exit(EXIT_FAILURE);
 659         } else if (ret > 0) {
 660                 exit(EXIT_SUCCESS);
 661         }
 662
 663         init_lttngtop();
 664
 665         bt_ctx = bt_context_create();
 666         ret = bt_context_add_traces_recursive(bt_ctx, opt_input_path, "ctf", NULL);
 667         if (ret < 0) {
 668                 fprintf(stderr, "[error] Opening the trace\n");
 669                 goto end;
 670         }
 671
 672         ret = check_requirements(bt_ctx);
 673         if (ret < 0) {
 674                 fprintf(stderr, "[error] missing mandatory context informations\n");
 675                 goto end;
 676         }
 677
 678         pthread_create(&display_thread, NULL, ncurses_display, (void *) NULL);
 679         pthread_create(&timer_thread, NULL, refresh_thread, (void *) NULL);
 680
 681         iter_trace(bt_ctx);
 682
 683         quit = 1;
 684         pthread_join(display_thread, NULL);
 685         pthread_join(timer_thread, NULL);
 686
 687 end:
 688         bt_context_put(bt_ctx);
 689         return 0;
 690 }