plugins/lttng-utils/debug-info.c

   1 /*
   2  * Babeltrace - Debug Information State Tracker
   3  *
   4  * Copyright (c) 2015 EfficiOS Inc. and Linux Foundation
   5  * Copyright (c) 2015 Philippe Proulx <pproulx@efficios.com>
   6  * Copyright (c) 2015 Antoine Busque <abusque@efficios.com>
   7  * Copyright (c) 2016 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   8  *
   9  * Permission is hereby granted, free of charge, to any person obtaining a copy
  10  * of this software and associated documentation files (the "Software"), to deal
  11  * in the Software without restriction, including without limitation the rights
  12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  13  * copies of the Software, and to permit persons to whom the Software is
  14  * furnished to do so, subject to the following conditions:
  15  *
  16  * The above copyright notice and this permission notice shall be included in
  17  * all copies or substantial portions of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  22  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  25  * SOFTWARE.
  26  */
  27
  28 #include <assert.h>
  29 #include <glib.h>
  30 #include "debug-info.h"
  31 #include "bin-info.h"
  32 #include "utils.h"
  33 #include "copy.h"
  34
  35 struct proc_debug_info_sources {
  36         /*
  37          * Hash table: base address (pointer to uint64_t) to bin info; owned by
  38          * proc_debug_info_sources.
  39          */
  40         GHashTable *baddr_to_bin_info;
  41
  42         /*
  43          * Hash table: IP (pointer to uint64_t) to (struct debug_info_source *);
  44          * owned by proc_debug_info_sources.
  45          */
  46         GHashTable *ip_to_debug_info_src;
  47 };
  48
  49 struct debug_info {
  50         struct debug_info_component *comp;
  51
  52         /*
  53          * Hash table of VPIDs (pointer to int64_t) to
  54          * (struct ctf_proc_debug_infos*); owned by debug_info.
  55          */
  56         GHashTable *vpid_to_proc_dbg_info_src;
  57         GQuark q_statedump_bin_info;
  58         GQuark q_statedump_debug_link;
  59         GQuark q_statedump_build_id;
  60         GQuark q_statedump_start;
  61         GQuark q_dl_open;
  62         GQuark q_lib_load;
  63         GQuark q_lib_unload;
  64 };
  65
  66 static
  67 int debug_info_init(struct debug_info *info)
  68 {
  69         info->q_statedump_bin_info = g_quark_from_string(
  70                         "lttng_ust_statedump:bin_info");
  71         info->q_statedump_debug_link = g_quark_from_string(
  72                         "lttng_ust_statedump:debug_link)");
  73         info->q_statedump_build_id = g_quark_from_string(
  74                         "lttng_ust_statedump:build_id");
  75         info->q_statedump_start = g_quark_from_string(
  76                         "lttng_ust_statedump:start");
  77         info->q_dl_open = g_quark_from_string("lttng_ust_dl:dlopen");
  78         info->q_lib_load = g_quark_from_string("lttng_ust_lib:load");
  79         info->q_lib_unload = g_quark_from_string("lttng_ust_lib:unload");
  80
  81         return bin_info_init();
  82 }
  83
  84 static
  85 void debug_info_source_destroy(struct debug_info_source *debug_info_src)
  86 {
  87         if (!debug_info_src) {
  88                 return;
  89         }
  90
  91         free(debug_info_src->func);
  92         free(debug_info_src->src_path);
  93         free(debug_info_src->bin_path);
  94         free(debug_info_src->bin_loc);
  95         g_free(debug_info_src);
  96 }
  97
  98 static
  99 struct debug_info_source *debug_info_source_create_from_bin(struct bin_info *bin,
 100                 uint64_t ip)
 101 {
 102         int ret;
 103         struct debug_info_source *debug_info_src = NULL;
 104         struct source_location *src_loc = NULL;
 105
 106         debug_info_src = g_new0(struct debug_info_source, 1);
 107
 108         if (!debug_info_src) {
 109                 goto end;
 110         }
 111
 112         /* Lookup function name */
 113         ret = bin_info_lookup_function_name(bin, ip, &debug_info_src->func);
 114         if (ret) {
 115                 goto error;
 116         }
 117
 118         /* Can't retrieve src_loc from ELF, or could not find binary, skip. */
 119         if (!bin->is_elf_only || !debug_info_src->func) {
 120                 /* Lookup source location */
 121                 ret = bin_info_lookup_source_location(bin, ip, &src_loc);
 122                 printf_verbose("Failed to lookup source location (err: %i)\n", ret);
 123         }
 124
 125         if (src_loc) {
 126                 debug_info_src->line_no = src_loc->line_no;
 127
 128                 if (src_loc->filename) {
 129                         debug_info_src->src_path = strdup(src_loc->filename);
 130                         if (!debug_info_src->src_path) {
 131                                 goto error;
 132                         }
 133
 134                         debug_info_src->short_src_path = get_filename_from_path(
 135                                         debug_info_src->src_path);
 136                 }
 137
 138                 source_location_destroy(src_loc);
 139         }
 140
 141         if (bin->elf_path) {
 142                 debug_info_src->bin_path = strdup(bin->elf_path);
 143                 if (!debug_info_src->bin_path) {
 144                         goto error;
 145                 }
 146
 147                 debug_info_src->short_bin_path = get_filename_from_path(
 148                                 debug_info_src->bin_path);
 149
 150                 ret = bin_info_get_bin_loc(bin, ip, &(debug_info_src->bin_loc));
 151                 if (ret) {
 152                         goto error;
 153                 }
 154         }
 155
 156 end:
 157         return debug_info_src;
 158
 159 error:
 160         debug_info_source_destroy(debug_info_src);
 161         return NULL;
 162 }
 163
 164 static
 165 void proc_debug_info_sources_destroy(
 166                 struct proc_debug_info_sources *proc_dbg_info_src)
 167 {
 168         if (!proc_dbg_info_src) {
 169                 return;
 170         }
 171
 172         if (proc_dbg_info_src->baddr_to_bin_info) {
 173                 g_hash_table_destroy(proc_dbg_info_src->baddr_to_bin_info);
 174         }
 175
 176         if (proc_dbg_info_src->ip_to_debug_info_src) {
 177                 g_hash_table_destroy(proc_dbg_info_src->ip_to_debug_info_src);
 178         }
 179
 180         g_free(proc_dbg_info_src);
 181 }
 182
 183 static
 184 struct proc_debug_info_sources *proc_debug_info_sources_create(void)
 185 {
 186         struct proc_debug_info_sources *proc_dbg_info_src = NULL;
 187
 188         proc_dbg_info_src = g_new0(struct proc_debug_info_sources, 1);
 189         if (!proc_dbg_info_src) {
 190                 goto end;
 191         }
 192
 193         proc_dbg_info_src->baddr_to_bin_info = g_hash_table_new_full(
 194                         g_int64_hash, g_int64_equal, (GDestroyNotify) g_free,
 195                         (GDestroyNotify) bin_info_destroy);
 196         if (!proc_dbg_info_src->baddr_to_bin_info) {
 197                 goto error;
 198         }
 199
 200         proc_dbg_info_src->ip_to_debug_info_src = g_hash_table_new_full(
 201                         g_int64_hash, g_int64_equal, (GDestroyNotify) g_free,
 202                         (GDestroyNotify) debug_info_source_destroy);
 203         if (!proc_dbg_info_src->ip_to_debug_info_src) {
 204                 goto error;
 205         }
 206
 207 end:
 208         return proc_dbg_info_src;
 209
 210 error:
 211         proc_debug_info_sources_destroy(proc_dbg_info_src);
 212         return NULL;
 213 }
 214
 215 static
 216 struct proc_debug_info_sources *proc_debug_info_sources_ht_get_entry(
 217                 GHashTable *ht, int64_t vpid)
 218 {
 219         gpointer key = g_new0(int64_t, 1);
 220         struct proc_debug_info_sources *proc_dbg_info_src = NULL;
 221
 222         if (!key) {
 223                 goto end;
 224         }
 225
 226         *((int64_t *) key) = vpid;
 227
 228         /* Exists? Return it */
 229         proc_dbg_info_src = g_hash_table_lookup(ht, key);
 230         if (proc_dbg_info_src) {
 231                 goto end;
 232         }
 233
 234         /* Otherwise, create and return it */
 235         proc_dbg_info_src = proc_debug_info_sources_create();
 236         if (!proc_dbg_info_src) {
 237                 goto end;
 238         }
 239
 240         g_hash_table_insert(ht, key, proc_dbg_info_src);
 241         /* Ownership passed to ht */
 242         key = NULL;
 243 end:
 244         g_free(key);
 245         return proc_dbg_info_src;
 246 }
 247
 248 static
 249 struct debug_info_source *proc_debug_info_sources_get_entry(
 250                 struct proc_debug_info_sources *proc_dbg_info_src, uint64_t ip)
 251 {
 252         struct debug_info_source *debug_info_src = NULL;
 253         gpointer key = g_new0(uint64_t, 1);
 254         GHashTableIter iter;
 255         gpointer baddr, value;
 256
 257         if (!key) {
 258                 goto end;
 259         }
 260
 261         *((uint64_t *) key) = ip;
 262
 263         /* Look in IP to debug infos hash table first. */
 264         debug_info_src = g_hash_table_lookup(
 265                         proc_dbg_info_src->ip_to_debug_info_src,
 266                         key);
 267         if (debug_info_src) {
 268                 goto end;
 269         }
 270
 271         /* Check in all bin_infos. */
 272         g_hash_table_iter_init(&iter, proc_dbg_info_src->baddr_to_bin_info);
 273
 274         while (g_hash_table_iter_next(&iter, &baddr, &value))
 275         {
 276                 struct bin_info *bin = value;
 277
 278                 if (!bin_info_has_address(value, ip)) {
 279                         continue;
 280                 }
 281
 282                 /*
 283                  * Found; add it to cache.
 284                  *
 285                  * FIXME: this should be bounded in size (and implement
 286                  * a caching policy), and entries should be prunned when
 287                  * libraries are unmapped.
 288                  */
 289                 debug_info_src = debug_info_source_create_from_bin(bin, ip);
 290                 if (debug_info_src) {
 291                         g_hash_table_insert(
 292                                         proc_dbg_info_src->ip_to_debug_info_src,
 293                                         key, debug_info_src);
 294                         /* Ownership passed to ht. */
 295                         key = NULL;
 296                 }
 297                 break;
 298         }
 299
 300 end:
 301         free(key);
 302         return debug_info_src;
 303 }
 304
 305 BT_HIDDEN
 306 struct debug_info_source *debug_info_query(struct debug_info *debug_info,
 307                 int64_t vpid, uint64_t ip)
 308 {
 309         struct debug_info_source *dbg_info_src = NULL;
 310         struct proc_debug_info_sources *proc_dbg_info_src;
 311
 312         proc_dbg_info_src = proc_debug_info_sources_ht_get_entry(
 313                         debug_info->vpid_to_proc_dbg_info_src, vpid);
 314         if (!proc_dbg_info_src) {
 315                 goto end;
 316         }
 317
 318         dbg_info_src = proc_debug_info_sources_get_entry(proc_dbg_info_src, ip);
 319
 320 end:
 321         return dbg_info_src;
 322 }
 323
 324 BT_HIDDEN
 325 struct debug_info *debug_info_create(struct debug_info_component *comp)
 326 {
 327         int ret;
 328         struct debug_info *debug_info;
 329
 330         debug_info = g_new0(struct debug_info, 1);
 331         if (!debug_info) {
 332                 goto end;
 333         }
 334
 335         debug_info->vpid_to_proc_dbg_info_src = g_hash_table_new_full(
 336                         g_int64_hash, g_int64_equal, (GDestroyNotify) g_free,
 337                         (GDestroyNotify) proc_debug_info_sources_destroy);
 338         if (!debug_info->vpid_to_proc_dbg_info_src) {
 339                 goto error;
 340         }
 341
 342         debug_info->comp = comp;
 343         ret = debug_info_init(debug_info);
 344         if (ret) {
 345                 goto error;
 346         }
 347
 348 end:
 349         return debug_info;
 350 error:
 351         g_free(debug_info);
 352         return NULL;
 353 }
 354
 355 BT_HIDDEN
 356 void debug_info_destroy(struct debug_info *debug_info)
 357 {
 358         if (!debug_info) {
 359                 goto end;
 360         }
 361
 362         if (debug_info->vpid_to_proc_dbg_info_src) {
 363                 g_hash_table_destroy(debug_info->vpid_to_proc_dbg_info_src);
 364         }
 365
 366         g_free(debug_info);
 367 end:
 368         return;
 369 }
 370
 371 static
 372 void handle_statedump_build_id_event(FILE *err, struct debug_info *debug_info,
 373                 struct bt_ctf_event *event)
 374 {
 375         struct proc_debug_info_sources *proc_dbg_info_src;
 376         struct bin_info *bin = NULL;
 377         int ret;
 378         int64_t vpid;
 379         uint64_t baddr;
 380
 381         ret = get_stream_event_context_int_field_value(err,
 382                         event, "_vpid", &vpid);
 383         if (ret) {
 384                 goto end;
 385         }
 386
 387         ret = get_payload_unsigned_int_field_value(err,
 388                         event, "_baddr", &baddr);
 389         if (ret) {
 390                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 391                                 __FILE__, __LINE__);
 392                 goto end;
 393         }
 394
 395         proc_dbg_info_src = proc_debug_info_sources_ht_get_entry(
 396                         debug_info->vpid_to_proc_dbg_info_src, vpid);
 397         if (!proc_dbg_info_src) {
 398                 goto end;
 399         }
 400
 401         bin = g_hash_table_lookup(proc_dbg_info_src->baddr_to_bin_info,
 402                         (gpointer) &baddr);
 403         if (!bin) {
 404                 /*
 405                  * The build_id event comes after the bin has been
 406                  * created. If it isn't found, just ignore this event.
 407                  */
 408                 goto end;
 409         }
 410
 411         ret = get_payload_build_id_field_value(err, event, "_build_id",
 412                         &bin->build_id, &bin->build_id_len);
 413         if (ret) {
 414                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 415                                 __FILE__, __LINE__);
 416                 goto end;
 417         }
 418
 419         /*
 420          * Reset the is_elf_only flag in case it had been set
 421          * previously, because we might find separate debug info using
 422          * the new build id information.
 423          */
 424         bin->is_elf_only = false;
 425
 426         // TODO
 427         //      bin_info_set_build_id(bin, build_id, build_id_len);
 428
 429 end:
 430         return;
 431 }
 432
 433 static
 434 void handle_statedump_debug_link_event(FILE *err, struct debug_info *debug_info,
 435                 struct bt_ctf_event *event)
 436 {
 437         struct proc_debug_info_sources *proc_dbg_info_src;
 438         struct bin_info *bin = NULL;
 439         int64_t vpid;
 440         uint64_t baddr;
 441         const char *filename = NULL;
 442         uint32_t crc32;
 443         uint64_t tmp;
 444         int ret;
 445
 446         ret = get_stream_event_context_int_field_value(err, event,
 447                         "_vpid", &vpid);
 448         if (ret) {
 449                 goto end;
 450         }
 451
 452         ret = get_payload_unsigned_int_field_value(err,
 453                         event, "_baddr", &baddr);
 454         if (ret) {
 455                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 456                                 __FILE__, __LINE__);
 457                 ret = -1;
 458                 goto end;
 459         }
 460
 461         ret = get_payload_unsigned_int_field_value(err, event, "_crc32", &tmp);
 462         if (ret) {
 463                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 464                                 __FILE__, __LINE__);
 465                 ret = -1;
 466                 goto end;
 467         }
 468         crc32 = (uint32_t) tmp;
 469
 470         ret = get_payload_string_field_value(err,
 471                         event, "_filename", &filename);
 472         if (ret) {
 473                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 474                                 __FILE__, __LINE__);
 475                 ret = -1;
 476                 goto end;
 477         }
 478
 479         proc_dbg_info_src = proc_debug_info_sources_ht_get_entry(
 480                         debug_info->vpid_to_proc_dbg_info_src, vpid);
 481         if (!proc_dbg_info_src) {
 482                 goto end;
 483         }
 484
 485         bin = g_hash_table_lookup(proc_dbg_info_src->baddr_to_bin_info,
 486                         (gpointer) &baddr);
 487         if (!bin) {
 488                 /*
 489                  * The debug_link event comes after the bin has been
 490                  * created. If it isn't found, just ignore this event.
 491                  */
 492                 goto end;
 493         }
 494
 495         bin_info_set_debug_link(bin, filename, crc32);
 496
 497 end:
 498         return;
 499 }
 500
 501 static
 502 void handle_bin_info_event(FILE *err, struct debug_info *debug_info,
 503                 struct bt_ctf_event *event, bool has_pic_field)
 504 {
 505         struct proc_debug_info_sources *proc_dbg_info_src;
 506         struct bin_info *bin;
 507         uint64_t baddr, memsz;
 508         int64_t vpid;
 509         const char *path;
 510         gpointer key = NULL;
 511         bool is_pic;
 512         int ret;
 513
 514         ret = get_payload_unsigned_int_field_value(err,
 515                         event, "_baddr", &baddr);
 516         if (ret) {
 517                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 518                                 __FILE__, __LINE__);
 519                 goto end;
 520         }
 521
 522         ret = get_payload_unsigned_int_field_value(err,
 523                         event, "_memsz", &memsz);
 524         if (ret) {
 525                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 526                                 __FILE__, __LINE__);
 527                 goto end;
 528         }
 529
 530         /*
 531          * This field is not produced by the dlopen event emitted before
 532          * lttng-ust 2.9.
 533          */
 534         ret = get_payload_string_field_value(err,
 535                         event, "_path", &path);
 536         if (ret || !path) {
 537                 goto end;
 538         }
 539
 540         if (has_pic_field) {
 541                 uint64_t tmp;
 542
 543                 ret = get_payload_unsigned_int_field_value(err,
 544                                 event, "_is_pic", &tmp);
 545                 if (ret) {
 546                         fprintf(err, "[error] %s in %s:%d\n", __func__,
 547                                         __FILE__, __LINE__);
 548                         ret = -1;
 549                         goto end;
 550                 }
 551                 is_pic = (tmp == 1);
 552         } else {
 553                 /*
 554                  * dlopen has no is_pic field, because the shared
 555                  * object is always PIC.
 556                  */
 557                 is_pic = true;
 558         }
 559
 560         ret = get_stream_event_context_int_field_value(err, event, "_vpid",
 561                         &vpid);
 562         if (ret) {
 563                 goto end;
 564         }
 565
 566         if (memsz == 0) {
 567                 /* Ignore VDSO. */
 568                 goto end;
 569         }
 570
 571         proc_dbg_info_src = proc_debug_info_sources_ht_get_entry(
 572                         debug_info->vpid_to_proc_dbg_info_src, vpid);
 573         if (!proc_dbg_info_src) {
 574                 goto end;
 575         }
 576
 577         key = g_new0(uint64_t, 1);
 578         if (!key) {
 579                 goto end;
 580         }
 581
 582         *((uint64_t *) key) = baddr;
 583
 584         bin = g_hash_table_lookup(proc_dbg_info_src->baddr_to_bin_info,
 585                         key);
 586         if (bin) {
 587                 goto end;
 588         }
 589
 590         bin = bin_info_create(path, baddr, memsz, is_pic,
 591                 debug_info->comp->arg_debug_dir,
 592                 debug_info->comp->arg_target_prefix);
 593         if (!bin) {
 594                 goto end;
 595         }
 596
 597         g_hash_table_insert(proc_dbg_info_src->baddr_to_bin_info,
 598                         key, bin);
 599         /* Ownership passed to ht. */
 600         key = NULL;
 601
 602 end:
 603         g_free(key);
 604         return;
 605 }
 606
 607 static inline
 608 void handle_statedump_bin_info_event(FILE *err, struct debug_info *debug_info,
 609                 struct bt_ctf_event *event)
 610 {
 611         handle_bin_info_event(err, debug_info, event, true);
 612 }
 613
 614 static inline
 615 void handle_lib_load_event(FILE *err, struct debug_info *debug_info,
 616                 struct bt_ctf_event *event)
 617 {
 618         handle_bin_info_event(err, debug_info, event, false);
 619 }
 620
 621 static inline
 622 void handle_lib_unload_event(FILE *err, struct debug_info *debug_info,
 623                 struct bt_ctf_event *event)
 624 {
 625         struct proc_debug_info_sources *proc_dbg_info_src;
 626         uint64_t baddr;
 627         int64_t vpid;
 628         gpointer key_ptr = NULL;
 629         int ret;
 630
 631         ret = get_payload_unsigned_int_field_value(err,
 632                         event, "_baddr", &baddr);
 633         if (ret) {
 634                 fprintf(err, "[error] %s in %s:%d\n", __func__,
 635                                 __FILE__, __LINE__);
 636                 ret = -1;
 637                 goto end;
 638         }
 639
 640         ret = get_stream_event_context_int_field_value(err, event, "_vpid",
 641                         &vpid);
 642         if (ret) {
 643                 goto end;
 644         }
 645
 646         proc_dbg_info_src = proc_debug_info_sources_ht_get_entry(
 647                         debug_info->vpid_to_proc_dbg_info_src, vpid);
 648         if (!proc_dbg_info_src) {
 649                 goto end;
 650         }
 651
 652         key_ptr = (gpointer) &baddr;
 653         (void) g_hash_table_remove(proc_dbg_info_src->baddr_to_bin_info,
 654                         key_ptr);
 655 end:
 656         return;
 657 }
 658
 659 static
 660 void handle_statedump_start(FILE *err, struct debug_info *debug_info,
 661                 struct bt_ctf_event *event)
 662 {
 663         struct proc_debug_info_sources *proc_dbg_info_src;
 664         int64_t vpid;
 665         int ret;
 666
 667         ret = get_stream_event_context_int_field_value(err, event,
 668                         "_vpid", &vpid);
 669         if (ret) {
 670                 goto end;
 671         }
 672
 673         proc_dbg_info_src = proc_debug_info_sources_ht_get_entry(
 674                         debug_info->vpid_to_proc_dbg_info_src, vpid);
 675         if (!proc_dbg_info_src) {
 676                 goto end;
 677         }
 678
 679         g_hash_table_remove_all(proc_dbg_info_src->baddr_to_bin_info);
 680         g_hash_table_remove_all(proc_dbg_info_src->ip_to_debug_info_src);
 681
 682 end:
 683         return;
 684 }
 685
 686 BT_HIDDEN
 687 void debug_info_handle_event(FILE *err, struct bt_ctf_event *event,
 688                 struct debug_info *debug_info)
 689 {
 690         struct bt_ctf_event_class *event_class;
 691         const char *event_name;
 692         GQuark q_event_name;
 693
 694         if (!debug_info || !event) {
 695                 goto end;
 696         }
 697         event_class = bt_ctf_event_get_class(event);
 698         if (!event_class) {
 699                 goto end;
 700         }
 701         event_name = bt_ctf_event_class_get_name(event_class);
 702         if (!event_name) {
 703                 goto end_put_class;
 704         }
 705         q_event_name = g_quark_try_string(event_name);
 706
 707         if (q_event_name == debug_info->q_statedump_bin_info) {
 708                 /* State dump */
 709                 handle_statedump_bin_info_event(err, debug_info, event);
 710         } else if (q_event_name == debug_info->q_dl_open ||
 711                         q_event_name == debug_info->q_lib_load) {
 712                 /*
 713                  * dl_open and lib_load events are both checked for since
 714                  * only dl_open was produced as of lttng-ust 2.8.
 715                  *
 716                  * lib_load, which is produced from lttng-ust 2.9+, is a lot
 717                  * more reliable since it will be emitted when other functions
 718                  * of the dlopen family are called (e.g. dlmopen) and when
 719                  * library are transitively loaded.
 720                  */
 721                 handle_lib_load_event(err, debug_info, event);
 722         } else if (q_event_name == debug_info->q_statedump_start) {
 723                 /* Start state dump */
 724                 handle_statedump_start(err, debug_info, event);
 725         } else if (q_event_name == debug_info->q_statedump_debug_link) {
 726                 /* Debug link info */
 727                 handle_statedump_debug_link_event(err, debug_info, event);
 728         } else if (q_event_name == debug_info->q_statedump_build_id) {
 729                 /* Build ID info */
 730                 handle_statedump_build_id_event(err, debug_info, event);
 731         } else if (q_event_name == debug_info-> q_lib_unload) {
 732                 handle_lib_unload_event(err, debug_info, event);
 733         }
 734
 735 end_put_class:
 736         bt_put(event_class);
 737 end:
 738         return;
 739 }