| 1 | /* |
| 2 | * Copyright (C) 2013 Paul Woegerer <paul_woegerer@mentor.com> |
| 3 | * Copyright (C) 2015 Antoine Busque <abusque@efficios.com> |
| 4 | * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | */ |
| 20 | |
| 21 | #define _GNU_SOURCE |
| 22 | #define _LGPL_SOURCE |
| 23 | #include <link.h> |
| 24 | #include <limits.h> |
| 25 | #include <stdio.h> |
| 26 | #include <stdint.h> |
| 27 | #include <stdlib.h> |
| 28 | #include <stdbool.h> |
| 29 | #include <sys/types.h> |
| 30 | #include <unistd.h> |
| 31 | |
| 32 | #include <lttng/ust-elf.h> |
| 33 | #include <helper.h> |
| 34 | #include "lttng-tracer-core.h" |
| 35 | #include "lttng-ust-statedump.h" |
| 36 | #include "jhash.h" |
| 37 | #include "getenv.h" |
| 38 | |
| 39 | #define TRACEPOINT_DEFINE |
| 40 | #include "ust_lib.h" /* Only define. */ |
| 41 | |
| 42 | #define TRACEPOINT_CREATE_PROBES |
| 43 | #define TP_SESSION_CHECK |
| 44 | #include "lttng-ust-statedump-provider.h" /* Define and create probes. */ |
| 45 | |
| 46 | struct dl_iterate_data { |
| 47 | int exec_found; |
| 48 | bool first; |
| 49 | bool cancel; |
| 50 | }; |
| 51 | |
| 52 | struct bin_info_data { |
| 53 | void *base_addr_ptr; |
| 54 | char resolved_path[PATH_MAX]; |
| 55 | char *dbg_file; |
| 56 | uint8_t *build_id; |
| 57 | uint64_t memsz; |
| 58 | size_t build_id_len; |
| 59 | int vdso; |
| 60 | uint32_t crc; |
| 61 | uint8_t is_pic; |
| 62 | uint8_t has_build_id; |
| 63 | uint8_t has_debug_link; |
| 64 | }; |
| 65 | |
| 66 | struct lttng_ust_dl_node { |
| 67 | struct bin_info_data bin_data; |
| 68 | struct cds_hlist_node node; |
| 69 | bool traced; |
| 70 | bool marked; |
| 71 | }; |
| 72 | |
| 73 | #define UST_DL_STATE_HASH_BITS 8 |
| 74 | #define UST_DL_STATE_TABLE_SIZE (1 << UST_DL_STATE_HASH_BITS) |
| 75 | struct cds_hlist_head dl_state_table[UST_DL_STATE_TABLE_SIZE]; |
| 76 | |
| 77 | typedef void (*tracepoint_cb)(struct lttng_session *session, void *priv); |
| 78 | |
| 79 | static |
| 80 | struct lttng_ust_dl_node *alloc_dl_node(const struct bin_info_data *bin_data) |
| 81 | { |
| 82 | struct lttng_ust_dl_node *e; |
| 83 | |
| 84 | e = zmalloc(sizeof(struct lttng_ust_dl_node)); |
| 85 | if (!e) |
| 86 | return NULL; |
| 87 | if (bin_data->dbg_file) { |
| 88 | e->bin_data.dbg_file = strdup(bin_data->dbg_file); |
| 89 | if (!e->bin_data.dbg_file) |
| 90 | goto error; |
| 91 | } |
| 92 | if (bin_data->build_id) { |
| 93 | e->bin_data.build_id = zmalloc(bin_data->build_id_len); |
| 94 | if (!e->bin_data.build_id) |
| 95 | goto error; |
| 96 | memcpy(e->bin_data.build_id, bin_data->build_id, |
| 97 | bin_data->build_id_len); |
| 98 | } |
| 99 | e->bin_data.base_addr_ptr = bin_data->base_addr_ptr; |
| 100 | memcpy(e->bin_data.resolved_path, bin_data->resolved_path, PATH_MAX); |
| 101 | e->bin_data.memsz = bin_data->memsz; |
| 102 | e->bin_data.build_id_len = bin_data->build_id_len; |
| 103 | e->bin_data.vdso = bin_data->vdso; |
| 104 | e->bin_data.crc = bin_data->crc; |
| 105 | e->bin_data.is_pic = bin_data->is_pic; |
| 106 | e->bin_data.has_build_id = bin_data->has_build_id; |
| 107 | e->bin_data.has_debug_link = bin_data->has_debug_link; |
| 108 | return e; |
| 109 | |
| 110 | error: |
| 111 | free(e->bin_data.build_id); |
| 112 | free(e->bin_data.dbg_file); |
| 113 | free(e); |
| 114 | return NULL; |
| 115 | } |
| 116 | |
| 117 | static |
| 118 | void free_dl_node(struct lttng_ust_dl_node *e) |
| 119 | { |
| 120 | free(e->bin_data.build_id); |
| 121 | free(e->bin_data.dbg_file); |
| 122 | free(e); |
| 123 | } |
| 124 | |
| 125 | /* Return 0 if same, nonzero if not. */ |
| 126 | static |
| 127 | int compare_bin_data(const struct bin_info_data *a, |
| 128 | const struct bin_info_data *b) |
| 129 | { |
| 130 | if (a->base_addr_ptr != b->base_addr_ptr) |
| 131 | return -1; |
| 132 | if (strcmp(a->resolved_path, b->resolved_path) != 0) |
| 133 | return -1; |
| 134 | if (a->dbg_file && !b->dbg_file) |
| 135 | return -1; |
| 136 | if (!a->dbg_file && b->dbg_file) |
| 137 | return -1; |
| 138 | if (a->dbg_file && strcmp(a->dbg_file, b->dbg_file) != 0) |
| 139 | return -1; |
| 140 | if (a->build_id && !b->build_id) |
| 141 | return -1; |
| 142 | if (!a->build_id && b->build_id) |
| 143 | return -1; |
| 144 | if (a->build_id_len != b->build_id_len) |
| 145 | return -1; |
| 146 | if (a->build_id && |
| 147 | memcmp(a->build_id, b->build_id, a->build_id_len) != 0) |
| 148 | return -1; |
| 149 | if (a->memsz != b->memsz) |
| 150 | return -1; |
| 151 | if (a->vdso != b->vdso) |
| 152 | return -1; |
| 153 | if (a->crc != b->crc) |
| 154 | return -1; |
| 155 | if (a->is_pic != b->is_pic) |
| 156 | return -1; |
| 157 | if (a->has_build_id != b->has_build_id) |
| 158 | return -1; |
| 159 | if (a->has_debug_link != b->has_debug_link) |
| 160 | return -1; |
| 161 | return 0; |
| 162 | } |
| 163 | |
| 164 | static |
| 165 | struct lttng_ust_dl_node *find_or_create_dl_node(struct bin_info_data *bin_data) |
| 166 | { |
| 167 | struct cds_hlist_head *head; |
| 168 | struct lttng_ust_dl_node *e; |
| 169 | unsigned int hash; |
| 170 | bool found = false; |
| 171 | |
| 172 | hash = jhash(&bin_data->base_addr_ptr, |
| 173 | sizeof(bin_data->base_addr_ptr), 0); |
| 174 | head = &dl_state_table[hash & (UST_DL_STATE_TABLE_SIZE - 1)]; |
| 175 | cds_hlist_for_each_entry_2(e, head, node) { |
| 176 | if (compare_bin_data(&e->bin_data, bin_data) != 0) |
| 177 | continue; |
| 178 | found = true; |
| 179 | break; |
| 180 | } |
| 181 | if (!found) { |
| 182 | /* Create */ |
| 183 | e = alloc_dl_node(bin_data); |
| 184 | if (!e) |
| 185 | return NULL; |
| 186 | cds_hlist_add_head(&e->node, head); |
| 187 | } |
| 188 | return e; |
| 189 | } |
| 190 | |
| 191 | static |
| 192 | void remove_dl_node(struct lttng_ust_dl_node *e) |
| 193 | { |
| 194 | cds_hlist_del(&e->node); |
| 195 | } |
| 196 | |
| 197 | /* |
| 198 | * Trace statedump event into all sessions owned by the caller thread |
| 199 | * for which statedump is pending. |
| 200 | */ |
| 201 | static |
| 202 | void trace_statedump_event(tracepoint_cb tp_cb, void *owner, void *priv) |
| 203 | { |
| 204 | struct cds_list_head *sessionsp; |
| 205 | struct lttng_session *session; |
| 206 | |
| 207 | sessionsp = _lttng_get_sessions(); |
| 208 | cds_list_for_each_entry(session, sessionsp, node) { |
| 209 | if (session->owner != owner) |
| 210 | continue; |
| 211 | if (!session->statedump_pending) |
| 212 | continue; |
| 213 | tp_cb(session, priv); |
| 214 | } |
| 215 | } |
| 216 | |
| 217 | static |
| 218 | void trace_bin_info_cb(struct lttng_session *session, void *priv) |
| 219 | { |
| 220 | struct bin_info_data *bin_data = (struct bin_info_data *) priv; |
| 221 | |
| 222 | tracepoint(lttng_ust_statedump, bin_info, |
| 223 | session, bin_data->base_addr_ptr, |
| 224 | bin_data->resolved_path, bin_data->memsz, |
| 225 | bin_data->is_pic, bin_data->has_build_id, |
| 226 | bin_data->has_debug_link); |
| 227 | } |
| 228 | |
| 229 | static |
| 230 | void trace_build_id_cb(struct lttng_session *session, void *priv) |
| 231 | { |
| 232 | struct bin_info_data *bin_data = (struct bin_info_data *) priv; |
| 233 | |
| 234 | tracepoint(lttng_ust_statedump, build_id, |
| 235 | session, bin_data->base_addr_ptr, |
| 236 | bin_data->build_id, bin_data->build_id_len); |
| 237 | } |
| 238 | |
| 239 | static |
| 240 | void trace_debug_link_cb(struct lttng_session *session, void *priv) |
| 241 | { |
| 242 | struct bin_info_data *bin_data = (struct bin_info_data *) priv; |
| 243 | |
| 244 | tracepoint(lttng_ust_statedump, debug_link, |
| 245 | session, bin_data->base_addr_ptr, |
| 246 | bin_data->dbg_file, bin_data->crc); |
| 247 | } |
| 248 | |
| 249 | static |
| 250 | void trace_start_cb(struct lttng_session *session, void *priv) |
| 251 | { |
| 252 | tracepoint(lttng_ust_statedump, start, session); |
| 253 | } |
| 254 | |
| 255 | static |
| 256 | void trace_end_cb(struct lttng_session *session, void *priv) |
| 257 | { |
| 258 | tracepoint(lttng_ust_statedump, end, session); |
| 259 | } |
| 260 | |
| 261 | static |
| 262 | int get_elf_info(struct bin_info_data *bin_data) |
| 263 | { |
| 264 | struct lttng_ust_elf *elf; |
| 265 | int ret = 0, found; |
| 266 | |
| 267 | elf = lttng_ust_elf_create(bin_data->resolved_path); |
| 268 | if (!elf) { |
| 269 | ret = -1; |
| 270 | goto end; |
| 271 | } |
| 272 | |
| 273 | ret = lttng_ust_elf_get_memsz(elf, &bin_data->memsz); |
| 274 | if (ret) { |
| 275 | goto end; |
| 276 | } |
| 277 | |
| 278 | found = 0; |
| 279 | ret = lttng_ust_elf_get_build_id(elf, &bin_data->build_id, |
| 280 | &bin_data->build_id_len, |
| 281 | &found); |
| 282 | if (ret) { |
| 283 | goto end; |
| 284 | } |
| 285 | bin_data->has_build_id = !!found; |
| 286 | found = 0; |
| 287 | ret = lttng_ust_elf_get_debug_link(elf, &bin_data->dbg_file, |
| 288 | &bin_data->crc, |
| 289 | &found); |
| 290 | if (ret) { |
| 291 | goto end; |
| 292 | } |
| 293 | bin_data->has_debug_link = !!found; |
| 294 | |
| 295 | bin_data->is_pic = lttng_ust_elf_is_pic(elf); |
| 296 | |
| 297 | end: |
| 298 | lttng_ust_elf_destroy(elf); |
| 299 | return ret; |
| 300 | } |
| 301 | |
| 302 | static |
| 303 | void trace_baddr(struct bin_info_data *bin_data, void *owner) |
| 304 | { |
| 305 | trace_statedump_event(trace_bin_info_cb, owner, bin_data); |
| 306 | |
| 307 | if (bin_data->has_build_id) |
| 308 | trace_statedump_event(trace_build_id_cb, owner, bin_data); |
| 309 | |
| 310 | if (bin_data->has_debug_link) |
| 311 | trace_statedump_event(trace_debug_link_cb, owner, bin_data); |
| 312 | } |
| 313 | |
| 314 | static |
| 315 | int extract_baddr(struct bin_info_data *bin_data) |
| 316 | { |
| 317 | int ret = 0; |
| 318 | struct lttng_ust_dl_node *e; |
| 319 | |
| 320 | if (!bin_data->vdso) { |
| 321 | ret = get_elf_info(bin_data); |
| 322 | if (ret) { |
| 323 | goto end; |
| 324 | } |
| 325 | } else { |
| 326 | bin_data->memsz = 0; |
| 327 | bin_data->has_build_id = 0; |
| 328 | bin_data->has_debug_link = 0; |
| 329 | } |
| 330 | |
| 331 | e = find_or_create_dl_node(bin_data); |
| 332 | if (!e) { |
| 333 | ret = -1; |
| 334 | goto end; |
| 335 | } |
| 336 | e->marked = true; |
| 337 | end: |
| 338 | free(bin_data->build_id); |
| 339 | bin_data->build_id = NULL; |
| 340 | free(bin_data->dbg_file); |
| 341 | bin_data->dbg_file = NULL; |
| 342 | return ret; |
| 343 | } |
| 344 | |
| 345 | static |
| 346 | void trace_statedump_start(void *owner) |
| 347 | { |
| 348 | trace_statedump_event(trace_start_cb, owner, NULL); |
| 349 | } |
| 350 | |
| 351 | static |
| 352 | void trace_statedump_end(void *owner) |
| 353 | { |
| 354 | trace_statedump_event(trace_end_cb, owner, NULL); |
| 355 | } |
| 356 | |
| 357 | static |
| 358 | void iter_begin(struct dl_iterate_data *data) |
| 359 | { |
| 360 | unsigned int i; |
| 361 | |
| 362 | /* |
| 363 | * UST lock nests within dynamic loader lock. |
| 364 | * |
| 365 | * Hold this lock across handling of the module listing to |
| 366 | * protect memory allocation at early process start, due to |
| 367 | * interactions with libc-wrapper lttng malloc instrumentation. |
| 368 | */ |
| 369 | if (ust_lock()) { |
| 370 | data->cancel = true; |
| 371 | return; |
| 372 | } |
| 373 | |
| 374 | /* Ensure all entries are unmarked. */ |
| 375 | for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { |
| 376 | struct cds_hlist_head *head; |
| 377 | struct lttng_ust_dl_node *e; |
| 378 | |
| 379 | head = &dl_state_table[i]; |
| 380 | cds_hlist_for_each_entry_2(e, head, node) |
| 381 | assert(!e->marked); |
| 382 | } |
| 383 | } |
| 384 | |
| 385 | static |
| 386 | void trace_lib_load(const struct bin_info_data *bin_data, void *ip) |
| 387 | { |
| 388 | tracepoint(lttng_ust_lib, load, |
| 389 | ip, bin_data->base_addr_ptr, bin_data->resolved_path, |
| 390 | bin_data->memsz, bin_data->has_build_id, |
| 391 | bin_data->has_debug_link); |
| 392 | |
| 393 | if (bin_data->has_build_id) { |
| 394 | tracepoint(lttng_ust_lib, build_id, |
| 395 | ip, bin_data->base_addr_ptr, bin_data->build_id, |
| 396 | bin_data->build_id_len); |
| 397 | } |
| 398 | |
| 399 | if (bin_data->has_debug_link) { |
| 400 | tracepoint(lttng_ust_lib, debug_link, |
| 401 | ip, bin_data->base_addr_ptr, bin_data->dbg_file, |
| 402 | bin_data->crc); |
| 403 | } |
| 404 | } |
| 405 | |
| 406 | static |
| 407 | void trace_lib_unload(const struct bin_info_data *bin_data, void *ip) |
| 408 | { |
| 409 | tracepoint(lttng_ust_lib, unload, ip, bin_data->base_addr_ptr); |
| 410 | } |
| 411 | |
| 412 | static |
| 413 | void iter_end(struct dl_iterate_data *data, void *ip) |
| 414 | { |
| 415 | unsigned int i; |
| 416 | |
| 417 | /* |
| 418 | * Iterate on hash table. |
| 419 | * For each marked, traced, do nothing. |
| 420 | * For each marked, not traced, trace lib open event. traced = true. |
| 421 | * For each unmarked, traced, trace lib close event. remove node. |
| 422 | * For each unmarked, not traced, remove node. |
| 423 | */ |
| 424 | for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { |
| 425 | struct cds_hlist_head *head; |
| 426 | struct lttng_ust_dl_node *e; |
| 427 | |
| 428 | head = &dl_state_table[i]; |
| 429 | cds_hlist_for_each_entry_2(e, head, node) { |
| 430 | if (e->marked) { |
| 431 | if (!e->traced) { |
| 432 | trace_lib_load(&e->bin_data, ip); |
| 433 | e->traced = true; |
| 434 | } |
| 435 | e->marked = false; |
| 436 | } else { |
| 437 | if (e->traced) |
| 438 | trace_lib_unload(&e->bin_data, ip); |
| 439 | remove_dl_node(e); |
| 440 | free_dl_node(e); |
| 441 | } |
| 442 | } |
| 443 | } |
| 444 | ust_unlock(); |
| 445 | } |
| 446 | |
| 447 | static |
| 448 | int extract_bin_info_events(struct dl_phdr_info *info, size_t size, void *_data) |
| 449 | { |
| 450 | int j, ret = 0; |
| 451 | struct dl_iterate_data *data = _data; |
| 452 | |
| 453 | if (data->first) { |
| 454 | iter_begin(data); |
| 455 | data->first = false; |
| 456 | } |
| 457 | |
| 458 | if (data->cancel) |
| 459 | goto end; |
| 460 | |
| 461 | for (j = 0; j < info->dlpi_phnum; j++) { |
| 462 | struct bin_info_data bin_data; |
| 463 | |
| 464 | if (info->dlpi_phdr[j].p_type != PT_LOAD) |
| 465 | continue; |
| 466 | |
| 467 | memset(&bin_data, 0, sizeof(bin_data)); |
| 468 | |
| 469 | /* Calculate virtual memory address of the loadable segment */ |
| 470 | bin_data.base_addr_ptr = (void *) info->dlpi_addr + |
| 471 | info->dlpi_phdr[j].p_vaddr; |
| 472 | |
| 473 | if ((info->dlpi_name == NULL || info->dlpi_name[0] == 0)) { |
| 474 | /* |
| 475 | * Only the first phdr without a dlpi_name |
| 476 | * encountered is considered as the program |
| 477 | * executable. The rest are vdsos. |
| 478 | */ |
| 479 | if (!data->exec_found) { |
| 480 | ssize_t path_len; |
| 481 | data->exec_found = 1; |
| 482 | |
| 483 | /* |
| 484 | * Use /proc/self/exe to resolve the |
| 485 | * executable's full path. |
| 486 | */ |
| 487 | path_len = readlink("/proc/self/exe", |
| 488 | bin_data.resolved_path, |
| 489 | PATH_MAX - 1); |
| 490 | if (path_len <= 0) |
| 491 | break; |
| 492 | |
| 493 | bin_data.resolved_path[path_len] = '\0'; |
| 494 | bin_data.vdso = 0; |
| 495 | } else { |
| 496 | snprintf(bin_data.resolved_path, |
| 497 | PATH_MAX - 1, "[vdso]"); |
| 498 | bin_data.vdso = 1; |
| 499 | } |
| 500 | } else { |
| 501 | /* |
| 502 | * For regular dl_phdr_info entries check if |
| 503 | * the path to the binary really exists. If not, |
| 504 | * treat as vdso and use dlpi_name as 'path'. |
| 505 | */ |
| 506 | if (!realpath(info->dlpi_name, |
| 507 | bin_data.resolved_path)) { |
| 508 | snprintf(bin_data.resolved_path, |
| 509 | PATH_MAX - 1, "[%s]", |
| 510 | info->dlpi_name); |
| 511 | bin_data.vdso = 1; |
| 512 | } else { |
| 513 | bin_data.vdso = 0; |
| 514 | } |
| 515 | } |
| 516 | |
| 517 | ret = extract_baddr(&bin_data); |
| 518 | break; |
| 519 | } |
| 520 | end: |
| 521 | return ret; |
| 522 | } |
| 523 | |
| 524 | static |
| 525 | void ust_dl_table_statedump(void *owner) |
| 526 | { |
| 527 | unsigned int i; |
| 528 | |
| 529 | if (ust_lock()) |
| 530 | goto end; |
| 531 | |
| 532 | /* Statedump each traced table entry into session for owner. */ |
| 533 | for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { |
| 534 | struct cds_hlist_head *head; |
| 535 | struct lttng_ust_dl_node *e; |
| 536 | |
| 537 | head = &dl_state_table[i]; |
| 538 | cds_hlist_for_each_entry_2(e, head, node) { |
| 539 | if (e->traced) |
| 540 | trace_baddr(&e->bin_data, owner); |
| 541 | } |
| 542 | } |
| 543 | |
| 544 | end: |
| 545 | ust_unlock(); |
| 546 | } |
| 547 | |
| 548 | void lttng_ust_dl_update(void *ip) |
| 549 | { |
| 550 | struct dl_iterate_data data; |
| 551 | |
| 552 | if (lttng_getenv("LTTNG_UST_WITHOUT_BADDR_STATEDUMP")) |
| 553 | return; |
| 554 | |
| 555 | /* |
| 556 | * Fixup lttng-ust TLS when called from dlopen/dlclose |
| 557 | * instrumentation. |
| 558 | */ |
| 559 | lttng_ust_fixup_tls(); |
| 560 | |
| 561 | data.exec_found = 0; |
| 562 | data.first = true; |
| 563 | data.cancel = false; |
| 564 | /* |
| 565 | * Iterate through the list of currently loaded shared objects and |
| 566 | * generate tables entries for loadable segments using |
| 567 | * extract_bin_info_events. |
| 568 | * Removed libraries are detected by mark-and-sweep: marking is |
| 569 | * done in the iteration over libraries, and sweeping is |
| 570 | * performed by iter_end(). |
| 571 | */ |
| 572 | dl_iterate_phdr(extract_bin_info_events, &data); |
| 573 | if (data.first) |
| 574 | iter_begin(&data); |
| 575 | iter_end(&data, ip); |
| 576 | } |
| 577 | |
| 578 | /* |
| 579 | * Generate a statedump of base addresses of all shared objects loaded |
| 580 | * by the traced application, as well as for the application's |
| 581 | * executable itself. |
| 582 | */ |
| 583 | static |
| 584 | int do_baddr_statedump(void *owner) |
| 585 | { |
| 586 | if (lttng_getenv("LTTNG_UST_WITHOUT_BADDR_STATEDUMP")) |
| 587 | return 0; |
| 588 | lttng_ust_dl_update(LTTNG_UST_CALLER_IP()); |
| 589 | ust_dl_table_statedump(owner); |
| 590 | return 0; |
| 591 | } |
| 592 | |
| 593 | /* |
| 594 | * Generate a statedump of a given traced application. A statedump is |
| 595 | * delimited by start and end events. For a given (process, session) |
| 596 | * pair, begin/end events are serialized and will match. However, in a |
| 597 | * session, statedumps from different processes may be |
| 598 | * interleaved. The vpid context should be used to identify which |
| 599 | * events belong to which process. |
| 600 | * |
| 601 | * Grab the ust_lock outside of the RCU read-side lock because we |
| 602 | * perform synchronize_rcu with the ust_lock held, which can trigger |
| 603 | * deadlocks otherwise. |
| 604 | */ |
| 605 | int do_lttng_ust_statedump(void *owner) |
| 606 | { |
| 607 | ust_lock_nocheck(); |
| 608 | trace_statedump_start(owner); |
| 609 | ust_unlock(); |
| 610 | |
| 611 | do_baddr_statedump(owner); |
| 612 | |
| 613 | ust_lock_nocheck(); |
| 614 | trace_statedump_end(owner); |
| 615 | ust_unlock(); |
| 616 | |
| 617 | return 0; |
| 618 | } |
| 619 | |
| 620 | void lttng_ust_statedump_init(void) |
| 621 | { |
| 622 | __tracepoints__init(); |
| 623 | __tracepoints__ptrs_init(); |
| 624 | __lttng_events_init__lttng_ust_statedump(); |
| 625 | lttng_ust_dl_update(LTTNG_UST_CALLER_IP()); |
| 626 | } |
| 627 | |
| 628 | static |
| 629 | void ust_dl_state_destroy(void) |
| 630 | { |
| 631 | unsigned int i; |
| 632 | |
| 633 | for (i = 0; i < UST_DL_STATE_TABLE_SIZE; i++) { |
| 634 | struct cds_hlist_head *head; |
| 635 | struct lttng_ust_dl_node *e, *tmp; |
| 636 | |
| 637 | head = &dl_state_table[i]; |
| 638 | cds_hlist_for_each_entry_safe_2(e, tmp, head, node) |
| 639 | free_dl_node(e); |
| 640 | CDS_INIT_HLIST_HEAD(head); |
| 641 | } |
| 642 | } |
| 643 | |
| 644 | void lttng_ust_statedump_destroy(void) |
| 645 | { |
| 646 | __lttng_events_exit__lttng_ust_statedump(); |
| 647 | __tracepoints__ptrs_destroy(); |
| 648 | __tracepoints__destroy(); |
| 649 | ust_dl_state_destroy(); |
| 650 | } |