| 1 | /* |
| 2 | * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca> |
| 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 only, |
| 6 | * as 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 _LGPL_SOURCE |
| 19 | #include <limits.h> |
| 20 | #include <inttypes.h> |
| 21 | #include <stdio.h> |
| 22 | #include <stdlib.h> |
| 23 | #include <string.h> |
| 24 | #include <sys/stat.h> |
| 25 | #include <urcu.h> |
| 26 | #include <dirent.h> |
| 27 | #include <sys/types.h> |
| 28 | #include <pthread.h> |
| 29 | |
| 30 | #include <common/common.h> |
| 31 | #include <common/utils.h> |
| 32 | #include <common/trace-chunk.h> |
| 33 | #include <common/sessiond-comm/sessiond-comm.h> |
| 34 | #include <lttng/location-internal.h> |
| 35 | #include "lttng-sessiond.h" |
| 36 | #include "kernel.h" |
| 37 | |
| 38 | #include "session.h" |
| 39 | #include "utils.h" |
| 40 | #include "trace-ust.h" |
| 41 | #include "timer.h" |
| 42 | |
| 43 | struct ltt_session_destroy_notifier_element { |
| 44 | ltt_session_destroy_notifier notifier; |
| 45 | void *user_data; |
| 46 | }; |
| 47 | |
| 48 | /* |
| 49 | * NOTES: |
| 50 | * |
| 51 | * No ltt_session.lock is taken here because those data structure are widely |
| 52 | * spread across the lttng-tools code base so before caling functions below |
| 53 | * that can read/write a session, the caller MUST acquire the session lock |
| 54 | * using session_lock() and session_unlock(). |
| 55 | */ |
| 56 | |
| 57 | /* |
| 58 | * Init tracing session list. |
| 59 | * |
| 60 | * Please see session.h for more explanation and correct usage of the list. |
| 61 | */ |
| 62 | static struct ltt_session_list ltt_session_list = { |
| 63 | .head = CDS_LIST_HEAD_INIT(ltt_session_list.head), |
| 64 | .lock = PTHREAD_MUTEX_INITIALIZER, |
| 65 | .removal_cond = PTHREAD_COND_INITIALIZER, |
| 66 | .next_uuid = 0, |
| 67 | }; |
| 68 | |
| 69 | /* These characters are forbidden in a session name. Used by validate_name. */ |
| 70 | static const char *forbidden_name_chars = "/"; |
| 71 | |
| 72 | /* Global hash table to keep the sessions, indexed by id. */ |
| 73 | static struct lttng_ht *ltt_sessions_ht_by_id = NULL; |
| 74 | |
| 75 | /* |
| 76 | * Validate the session name for forbidden characters. |
| 77 | * |
| 78 | * Return 0 on success else -1 meaning a forbidden char. has been found. |
| 79 | */ |
| 80 | static int validate_name(const char *name) |
| 81 | { |
| 82 | int ret; |
| 83 | char *tok, *tmp_name; |
| 84 | |
| 85 | assert(name); |
| 86 | |
| 87 | tmp_name = strdup(name); |
| 88 | if (!tmp_name) { |
| 89 | /* ENOMEM here. */ |
| 90 | ret = -1; |
| 91 | goto error; |
| 92 | } |
| 93 | |
| 94 | tok = strpbrk(tmp_name, forbidden_name_chars); |
| 95 | if (tok) { |
| 96 | DBG("Session name %s contains a forbidden character", name); |
| 97 | /* Forbidden character has been found. */ |
| 98 | ret = -1; |
| 99 | goto error; |
| 100 | } |
| 101 | ret = 0; |
| 102 | |
| 103 | error: |
| 104 | free(tmp_name); |
| 105 | return ret; |
| 106 | } |
| 107 | |
| 108 | /* |
| 109 | * Add a ltt_session structure to the global list. |
| 110 | * |
| 111 | * The caller MUST acquire the session list lock before. |
| 112 | * Returns the unique identifier for the session. |
| 113 | */ |
| 114 | static uint64_t add_session_list(struct ltt_session *ls) |
| 115 | { |
| 116 | assert(ls); |
| 117 | |
| 118 | cds_list_add(&ls->list, <t_session_list.head); |
| 119 | return ltt_session_list.next_uuid++; |
| 120 | } |
| 121 | |
| 122 | /* |
| 123 | * Delete a ltt_session structure to the global list. |
| 124 | * |
| 125 | * The caller MUST acquire the session list lock before. |
| 126 | */ |
| 127 | static void del_session_list(struct ltt_session *ls) |
| 128 | { |
| 129 | assert(ls); |
| 130 | |
| 131 | cds_list_del(&ls->list); |
| 132 | } |
| 133 | |
| 134 | /* |
| 135 | * Return a pointer to the session list. |
| 136 | */ |
| 137 | struct ltt_session_list *session_get_list(void) |
| 138 | { |
| 139 | return <t_session_list; |
| 140 | } |
| 141 | |
| 142 | /* |
| 143 | * Returns once the session list is empty. |
| 144 | */ |
| 145 | void session_list_wait_empty(void) |
| 146 | { |
| 147 | pthread_mutex_lock(<t_session_list.lock); |
| 148 | while (!cds_list_empty(<t_session_list.head)) { |
| 149 | pthread_cond_wait(<t_session_list.removal_cond, |
| 150 | <t_session_list.lock); |
| 151 | } |
| 152 | pthread_mutex_unlock(<t_session_list.lock); |
| 153 | } |
| 154 | |
| 155 | /* |
| 156 | * Acquire session list lock |
| 157 | */ |
| 158 | void session_lock_list(void) |
| 159 | { |
| 160 | pthread_mutex_lock(<t_session_list.lock); |
| 161 | } |
| 162 | |
| 163 | /* |
| 164 | * Try to acquire session list lock |
| 165 | */ |
| 166 | int session_trylock_list(void) |
| 167 | { |
| 168 | return pthread_mutex_trylock(<t_session_list.lock); |
| 169 | } |
| 170 | |
| 171 | /* |
| 172 | * Release session list lock |
| 173 | */ |
| 174 | void session_unlock_list(void) |
| 175 | { |
| 176 | pthread_mutex_unlock(<t_session_list.lock); |
| 177 | } |
| 178 | |
| 179 | /* |
| 180 | * Get the session's consumer destination type. |
| 181 | * |
| 182 | * The caller must hold the session lock. |
| 183 | */ |
| 184 | enum consumer_dst_type session_get_consumer_destination_type( |
| 185 | const struct ltt_session *session) |
| 186 | { |
| 187 | /* |
| 188 | * The output information is duplicated in both of those session types. |
| 189 | * Hence, it doesn't matter from which it is retrieved. However, it is |
| 190 | * possible for only one of them to be set. |
| 191 | */ |
| 192 | return session->kernel_session ? |
| 193 | session->kernel_session->consumer->type : |
| 194 | session->ust_session->consumer->type; |
| 195 | } |
| 196 | |
| 197 | /* |
| 198 | * Get the session's consumer network hostname. |
| 199 | * The caller must ensure that the destination is of type "net". |
| 200 | * |
| 201 | * The caller must hold the session lock. |
| 202 | */ |
| 203 | const char *session_get_net_consumer_hostname(const struct ltt_session *session) |
| 204 | { |
| 205 | const char *hostname = NULL; |
| 206 | const struct consumer_output *output; |
| 207 | |
| 208 | output = session->kernel_session ? |
| 209 | session->kernel_session->consumer : |
| 210 | session->ust_session->consumer; |
| 211 | |
| 212 | /* |
| 213 | * hostname is assumed to be the same for both control and data |
| 214 | * connections. |
| 215 | */ |
| 216 | switch (output->dst.net.control.dtype) { |
| 217 | case LTTNG_DST_IPV4: |
| 218 | hostname = output->dst.net.control.dst.ipv4; |
| 219 | break; |
| 220 | case LTTNG_DST_IPV6: |
| 221 | hostname = output->dst.net.control.dst.ipv6; |
| 222 | break; |
| 223 | default: |
| 224 | abort(); |
| 225 | } |
| 226 | return hostname; |
| 227 | } |
| 228 | |
| 229 | /* |
| 230 | * Get the session's consumer network control and data ports. |
| 231 | * The caller must ensure that the destination is of type "net". |
| 232 | * |
| 233 | * The caller must hold the session lock. |
| 234 | */ |
| 235 | void session_get_net_consumer_ports(const struct ltt_session *session, |
| 236 | uint16_t *control_port, uint16_t *data_port) |
| 237 | { |
| 238 | const struct consumer_output *output; |
| 239 | |
| 240 | output = session->kernel_session ? |
| 241 | session->kernel_session->consumer : |
| 242 | session->ust_session->consumer; |
| 243 | *control_port = output->dst.net.control.port; |
| 244 | *data_port = output->dst.net.data.port; |
| 245 | } |
| 246 | |
| 247 | /* |
| 248 | * Get the location of the latest trace archive produced by a rotation. |
| 249 | * |
| 250 | * The caller must hold the session lock. |
| 251 | */ |
| 252 | struct lttng_trace_archive_location *session_get_trace_archive_location( |
| 253 | const struct ltt_session *session) |
| 254 | { |
| 255 | int ret; |
| 256 | struct lttng_trace_archive_location *location = NULL; |
| 257 | char *chunk_path = NULL; |
| 258 | |
| 259 | if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED || |
| 260 | !session->last_archived_chunk_name) { |
| 261 | goto end; |
| 262 | } |
| 263 | |
| 264 | ret = asprintf(&chunk_path, "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s", |
| 265 | session_get_base_path(session), |
| 266 | session->last_archived_chunk_name); |
| 267 | if (ret == -1) { |
| 268 | goto end; |
| 269 | } |
| 270 | |
| 271 | switch (session_get_consumer_destination_type(session)) { |
| 272 | case CONSUMER_DST_LOCAL: |
| 273 | location = lttng_trace_archive_location_local_create( |
| 274 | chunk_path); |
| 275 | break; |
| 276 | case CONSUMER_DST_NET: |
| 277 | { |
| 278 | const char *hostname; |
| 279 | uint16_t control_port, data_port; |
| 280 | |
| 281 | hostname = session_get_net_consumer_hostname(session); |
| 282 | session_get_net_consumer_ports(session, |
| 283 | &control_port, |
| 284 | &data_port); |
| 285 | location = lttng_trace_archive_location_relay_create( |
| 286 | hostname, |
| 287 | LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP, |
| 288 | control_port, data_port, chunk_path); |
| 289 | break; |
| 290 | } |
| 291 | default: |
| 292 | abort(); |
| 293 | } |
| 294 | end: |
| 295 | free(chunk_path); |
| 296 | return location; |
| 297 | } |
| 298 | |
| 299 | /* |
| 300 | * Allocate the ltt_sessions_ht_by_id HT. |
| 301 | * |
| 302 | * The session list lock must be held. |
| 303 | */ |
| 304 | int ltt_sessions_ht_alloc(void) |
| 305 | { |
| 306 | int ret = 0; |
| 307 | |
| 308 | DBG("Allocating ltt_sessions_ht_by_id"); |
| 309 | ltt_sessions_ht_by_id = lttng_ht_new(0, LTTNG_HT_TYPE_U64); |
| 310 | if (!ltt_sessions_ht_by_id) { |
| 311 | ret = -1; |
| 312 | ERR("Failed to allocate ltt_sessions_ht_by_id"); |
| 313 | goto end; |
| 314 | } |
| 315 | end: |
| 316 | return ret; |
| 317 | } |
| 318 | |
| 319 | /* |
| 320 | * Destroy the ltt_sessions_ht_by_id HT. |
| 321 | * |
| 322 | * The session list lock must be held. |
| 323 | */ |
| 324 | static void ltt_sessions_ht_destroy(void) |
| 325 | { |
| 326 | if (!ltt_sessions_ht_by_id) { |
| 327 | return; |
| 328 | } |
| 329 | ht_cleanup_push(ltt_sessions_ht_by_id); |
| 330 | ltt_sessions_ht_by_id = NULL; |
| 331 | } |
| 332 | |
| 333 | /* |
| 334 | * Add a ltt_session to the ltt_sessions_ht_by_id. |
| 335 | * If unallocated, the ltt_sessions_ht_by_id HT is allocated. |
| 336 | * The session list lock must be held. |
| 337 | */ |
| 338 | static void add_session_ht(struct ltt_session *ls) |
| 339 | { |
| 340 | int ret; |
| 341 | |
| 342 | assert(ls); |
| 343 | |
| 344 | if (!ltt_sessions_ht_by_id) { |
| 345 | ret = ltt_sessions_ht_alloc(); |
| 346 | if (ret) { |
| 347 | ERR("Error allocating the sessions HT"); |
| 348 | goto end; |
| 349 | } |
| 350 | } |
| 351 | lttng_ht_node_init_u64(&ls->node, ls->id); |
| 352 | lttng_ht_add_unique_u64(ltt_sessions_ht_by_id, &ls->node); |
| 353 | |
| 354 | end: |
| 355 | return; |
| 356 | } |
| 357 | |
| 358 | /* |
| 359 | * Test if ltt_sessions_ht_by_id is empty. |
| 360 | * Return 1 if empty, 0 if not empty. |
| 361 | * The session list lock must be held. |
| 362 | */ |
| 363 | static int ltt_sessions_ht_empty(void) |
| 364 | { |
| 365 | int ret; |
| 366 | |
| 367 | if (!ltt_sessions_ht_by_id) { |
| 368 | ret = 1; |
| 369 | goto end; |
| 370 | } |
| 371 | |
| 372 | ret = lttng_ht_get_count(ltt_sessions_ht_by_id) ? 0 : 1; |
| 373 | end: |
| 374 | return ret; |
| 375 | } |
| 376 | |
| 377 | /* |
| 378 | * Remove a ltt_session from the ltt_sessions_ht_by_id. |
| 379 | * If empty, the ltt_sessions_ht_by_id HT is freed. |
| 380 | * The session list lock must be held. |
| 381 | */ |
| 382 | static void del_session_ht(struct ltt_session *ls) |
| 383 | { |
| 384 | struct lttng_ht_iter iter; |
| 385 | int ret; |
| 386 | |
| 387 | assert(ls); |
| 388 | assert(ltt_sessions_ht_by_id); |
| 389 | |
| 390 | iter.iter.node = &ls->node.node; |
| 391 | ret = lttng_ht_del(ltt_sessions_ht_by_id, &iter); |
| 392 | assert(!ret); |
| 393 | |
| 394 | if (ltt_sessions_ht_empty()) { |
| 395 | DBG("Empty ltt_sessions_ht_by_id, destroying it"); |
| 396 | ltt_sessions_ht_destroy(); |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | /* |
| 401 | * Acquire session lock |
| 402 | */ |
| 403 | void session_lock(struct ltt_session *session) |
| 404 | { |
| 405 | assert(session); |
| 406 | |
| 407 | pthread_mutex_lock(&session->lock); |
| 408 | } |
| 409 | |
| 410 | /* |
| 411 | * Release session lock |
| 412 | */ |
| 413 | void session_unlock(struct ltt_session *session) |
| 414 | { |
| 415 | assert(session); |
| 416 | |
| 417 | pthread_mutex_unlock(&session->lock); |
| 418 | } |
| 419 | |
| 420 | static |
| 421 | int _session_set_trace_chunk_no_lock_check(struct ltt_session *session, |
| 422 | struct lttng_trace_chunk *new_trace_chunk, |
| 423 | struct lttng_trace_chunk **_current_trace_chunk) |
| 424 | { |
| 425 | int ret; |
| 426 | unsigned int i, refs_to_acquire = 0, refs_acquired = 0, refs_to_release = 0; |
| 427 | struct cds_lfht_iter iter; |
| 428 | struct consumer_socket *socket; |
| 429 | struct lttng_trace_chunk *current_trace_chunk; |
| 430 | uint64_t chunk_id; |
| 431 | enum lttng_trace_chunk_status chunk_status; |
| 432 | const uint64_t relayd_id = session->consumer->net_seq_index; |
| 433 | const bool is_local_trace = relayd_id == -1ULL; |
| 434 | |
| 435 | rcu_read_lock(); |
| 436 | /* |
| 437 | * Ownership of current trace chunk is transferred to |
| 438 | * `current_trace_chunk`. |
| 439 | */ |
| 440 | current_trace_chunk = session->current_trace_chunk; |
| 441 | session->current_trace_chunk = NULL; |
| 442 | if (session->ust_session) { |
| 443 | lttng_trace_chunk_put( |
| 444 | session->ust_session->current_trace_chunk); |
| 445 | session->ust_session->current_trace_chunk = NULL; |
| 446 | } |
| 447 | if (session->kernel_session) { |
| 448 | lttng_trace_chunk_put( |
| 449 | session->kernel_session->current_trace_chunk); |
| 450 | session->kernel_session->current_trace_chunk = NULL; |
| 451 | } |
| 452 | if (!new_trace_chunk) { |
| 453 | ret = 0; |
| 454 | goto end; |
| 455 | } |
| 456 | chunk_status = lttng_trace_chunk_get_id(new_trace_chunk, &chunk_id); |
| 457 | assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK); |
| 458 | |
| 459 | refs_to_acquire = 1; |
| 460 | refs_to_acquire += !!session->ust_session; |
| 461 | refs_to_acquire += !!session->kernel_session; |
| 462 | |
| 463 | for (refs_acquired = 0; refs_acquired < refs_to_acquire; |
| 464 | refs_acquired++) { |
| 465 | if (!lttng_trace_chunk_get(new_trace_chunk)) { |
| 466 | ERR("Failed to acquire reference to new trace chunk of session \"%s\"", |
| 467 | session->name); |
| 468 | goto error; |
| 469 | } |
| 470 | } |
| 471 | |
| 472 | if (session->ust_session) { |
| 473 | session->ust_session->current_trace_chunk = new_trace_chunk; |
| 474 | if (is_local_trace) { |
| 475 | enum lttng_error_code ret_error_code; |
| 476 | |
| 477 | ret_error_code = ust_app_create_channel_subdirectories( |
| 478 | session->ust_session); |
| 479 | if (ret_error_code != LTTNG_OK) { |
| 480 | ret = -ret_error_code; |
| 481 | goto error; |
| 482 | } |
| 483 | } |
| 484 | cds_lfht_for_each_entry( |
| 485 | session->ust_session->consumer->socks->ht, |
| 486 | &iter, socket, node.node) { |
| 487 | pthread_mutex_lock(socket->lock); |
| 488 | ret = consumer_create_trace_chunk(socket, |
| 489 | relayd_id, |
| 490 | session->id, new_trace_chunk); |
| 491 | pthread_mutex_unlock(socket->lock); |
| 492 | if (ret) { |
| 493 | goto error; |
| 494 | } |
| 495 | } |
| 496 | } |
| 497 | if (session->kernel_session) { |
| 498 | session->kernel_session->current_trace_chunk = new_trace_chunk; |
| 499 | if (is_local_trace) { |
| 500 | enum lttng_error_code ret_error_code; |
| 501 | |
| 502 | ret_error_code = kernel_create_channel_subdirectories( |
| 503 | session->kernel_session); |
| 504 | if (ret_error_code != LTTNG_OK) { |
| 505 | ret = -ret_error_code; |
| 506 | goto error; |
| 507 | } |
| 508 | } |
| 509 | cds_lfht_for_each_entry( |
| 510 | session->kernel_session->consumer->socks->ht, |
| 511 | &iter, socket, node.node) { |
| 512 | pthread_mutex_lock(socket->lock); |
| 513 | ret = consumer_create_trace_chunk(socket, |
| 514 | relayd_id, |
| 515 | session->id, new_trace_chunk); |
| 516 | pthread_mutex_unlock(socket->lock); |
| 517 | if (ret) { |
| 518 | goto error; |
| 519 | } |
| 520 | } |
| 521 | } |
| 522 | |
| 523 | /* |
| 524 | * Update local current trace chunk state last, only if all remote |
| 525 | * creations succeeded. |
| 526 | */ |
| 527 | session->current_trace_chunk = new_trace_chunk; |
| 528 | LTTNG_OPTIONAL_SET(&session->most_recent_chunk_id, chunk_id); |
| 529 | end: |
| 530 | if (_current_trace_chunk) { |
| 531 | *_current_trace_chunk = current_trace_chunk; |
| 532 | current_trace_chunk = NULL; |
| 533 | } |
| 534 | end_no_move: |
| 535 | rcu_read_unlock(); |
| 536 | lttng_trace_chunk_put(current_trace_chunk); |
| 537 | return ret; |
| 538 | error: |
| 539 | if (session->ust_session) { |
| 540 | session->ust_session->current_trace_chunk = NULL; |
| 541 | } |
| 542 | if (session->kernel_session) { |
| 543 | session->kernel_session->current_trace_chunk = NULL; |
| 544 | } |
| 545 | /* |
| 546 | * Release references taken in the case where all references could not |
| 547 | * be acquired. |
| 548 | */ |
| 549 | refs_to_release = refs_to_acquire - refs_acquired; |
| 550 | for (i = 0; i < refs_to_release; i++) { |
| 551 | lttng_trace_chunk_put(new_trace_chunk); |
| 552 | } |
| 553 | ret = -1; |
| 554 | goto end_no_move; |
| 555 | } |
| 556 | |
| 557 | static |
| 558 | bool output_supports_trace_chunks(const struct ltt_session *session) |
| 559 | { |
| 560 | if (session->consumer->type == CONSUMER_DST_LOCAL) { |
| 561 | return true; |
| 562 | } else { |
| 563 | struct consumer_output *output; |
| 564 | |
| 565 | if (session->ust_session) { |
| 566 | output = session->ust_session->consumer; |
| 567 | } else if (session->kernel_session) { |
| 568 | output = session->kernel_session->consumer; |
| 569 | } else { |
| 570 | abort(); |
| 571 | } |
| 572 | |
| 573 | if (output->relay_major_version > 2) { |
| 574 | return true; |
| 575 | } else if (output->relay_major_version == 2 && |
| 576 | output->relay_minor_version >= 11) { |
| 577 | return true; |
| 578 | } |
| 579 | } |
| 580 | return false; |
| 581 | } |
| 582 | |
| 583 | struct lttng_trace_chunk *session_create_new_trace_chunk( |
| 584 | struct ltt_session *session, |
| 585 | const char *session_base_path_override, |
| 586 | const char *chunk_name_override) |
| 587 | { |
| 588 | int ret; |
| 589 | struct lttng_trace_chunk *trace_chunk = NULL; |
| 590 | enum lttng_trace_chunk_status chunk_status; |
| 591 | const time_t chunk_creation_ts = time(NULL); |
| 592 | const bool is_local_trace = |
| 593 | session->consumer->type == CONSUMER_DST_LOCAL; |
| 594 | const char *base_path = session_base_path_override ? : |
| 595 | session_get_base_path(session); |
| 596 | struct lttng_directory_handle session_output_directory; |
| 597 | const struct lttng_credentials session_credentials = { |
| 598 | .uid = session->uid, |
| 599 | .gid = session->gid, |
| 600 | }; |
| 601 | uint64_t next_chunk_id; |
| 602 | |
| 603 | if (chunk_creation_ts == (time_t) -1) { |
| 604 | PERROR("Failed to sample time while creation session \"%s\" trace chunk", |
| 605 | session->name); |
| 606 | goto error; |
| 607 | } |
| 608 | |
| 609 | if (!output_supports_trace_chunks(session)) { |
| 610 | goto end; |
| 611 | } |
| 612 | next_chunk_id = session->most_recent_chunk_id.is_set ? |
| 613 | session->most_recent_chunk_id.value + 1 : 0; |
| 614 | |
| 615 | trace_chunk = lttng_trace_chunk_create(next_chunk_id, |
| 616 | chunk_creation_ts); |
| 617 | if (!trace_chunk) { |
| 618 | goto error; |
| 619 | } |
| 620 | |
| 621 | if (chunk_name_override) { |
| 622 | chunk_status = lttng_trace_chunk_override_name(trace_chunk, |
| 623 | chunk_name_override); |
| 624 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 625 | goto error; |
| 626 | } |
| 627 | } |
| 628 | |
| 629 | if (!is_local_trace) { |
| 630 | /* |
| 631 | * No need to set crendentials and output directory |
| 632 | * for remote trace chunks. |
| 633 | */ |
| 634 | goto end; |
| 635 | } |
| 636 | |
| 637 | chunk_status = lttng_trace_chunk_set_credentials(trace_chunk, |
| 638 | &session_credentials); |
| 639 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 640 | goto error; |
| 641 | } |
| 642 | |
| 643 | DBG("Creating base output directory of session \"%s\" at %s", |
| 644 | session->name, base_path); |
| 645 | ret = utils_mkdir_recursive(base_path, S_IRWXU | S_IRWXG, |
| 646 | session->uid, session->gid); |
| 647 | if (ret) { |
| 648 | goto error; |
| 649 | } |
| 650 | ret = lttng_directory_handle_init(&session_output_directory, |
| 651 | base_path); |
| 652 | if (ret) { |
| 653 | goto error; |
| 654 | } |
| 655 | chunk_status = lttng_trace_chunk_set_as_owner(trace_chunk, |
| 656 | &session_output_directory); |
| 657 | lttng_directory_handle_fini(&session_output_directory); |
| 658 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 659 | goto error; |
| 660 | } |
| 661 | end: |
| 662 | return trace_chunk; |
| 663 | error: |
| 664 | lttng_trace_chunk_put(trace_chunk); |
| 665 | trace_chunk = NULL; |
| 666 | goto end; |
| 667 | } |
| 668 | |
| 669 | int session_close_trace_chunk(const struct ltt_session *session, |
| 670 | struct lttng_trace_chunk *trace_chunk) |
| 671 | { |
| 672 | int ret = 0; |
| 673 | bool error_occurred = false; |
| 674 | struct cds_lfht_iter iter; |
| 675 | struct consumer_socket *socket; |
| 676 | enum lttng_trace_chunk_status chunk_status; |
| 677 | const time_t chunk_close_timestamp = time(NULL); |
| 678 | |
| 679 | if (chunk_close_timestamp == (time_t) -1) { |
| 680 | ERR("Failed to sample the close timestamp of the current trace chunk of session \"%s\"", |
| 681 | session->name); |
| 682 | ret = -1; |
| 683 | goto end; |
| 684 | } |
| 685 | chunk_status = lttng_trace_chunk_set_close_timestamp(trace_chunk, |
| 686 | chunk_close_timestamp); |
| 687 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 688 | ERR("Failed to set the close timestamp of the current trace chunk of session \"%s\"", |
| 689 | session->name); |
| 690 | ret = -1; |
| 691 | goto end; |
| 692 | } |
| 693 | |
| 694 | if (session->ust_session) { |
| 695 | cds_lfht_for_each_entry( |
| 696 | session->ust_session->consumer->socks->ht, |
| 697 | &iter, socket, node.node) { |
| 698 | pthread_mutex_lock(socket->lock); |
| 699 | ret = consumer_close_trace_chunk(socket, |
| 700 | session->consumer->net_seq_index, |
| 701 | session->id, |
| 702 | trace_chunk); |
| 703 | pthread_mutex_unlock(socket->lock); |
| 704 | if (ret) { |
| 705 | ERR("Failed to close trace chunk on user space consumer"); |
| 706 | error_occurred = true; |
| 707 | } |
| 708 | } |
| 709 | } |
| 710 | if (session->kernel_session) { |
| 711 | cds_lfht_for_each_entry( |
| 712 | session->kernel_session->consumer->socks->ht, |
| 713 | &iter, socket, node.node) { |
| 714 | pthread_mutex_lock(socket->lock); |
| 715 | ret = consumer_close_trace_chunk(socket, |
| 716 | session->consumer->net_seq_index, |
| 717 | session->id, |
| 718 | trace_chunk); |
| 719 | pthread_mutex_unlock(socket->lock); |
| 720 | if (ret) { |
| 721 | ERR("Failed to close trace chunk on kernel consumer"); |
| 722 | error_occurred = true; |
| 723 | } |
| 724 | } |
| 725 | } |
| 726 | ret = error_occurred ? -1 : 0; |
| 727 | end: |
| 728 | return ret; |
| 729 | } |
| 730 | |
| 731 | /* |
| 732 | * Set a session's current trace chunk. |
| 733 | * |
| 734 | * Must be called with the session lock held. |
| 735 | */ |
| 736 | int session_set_trace_chunk(struct ltt_session *session, |
| 737 | struct lttng_trace_chunk *new_trace_chunk, |
| 738 | struct lttng_trace_chunk **current_trace_chunk) |
| 739 | { |
| 740 | ASSERT_LOCKED(session->lock); |
| 741 | return _session_set_trace_chunk_no_lock_check(session, new_trace_chunk, |
| 742 | current_trace_chunk); |
| 743 | } |
| 744 | |
| 745 | static |
| 746 | void session_notify_destruction(const struct ltt_session *session) |
| 747 | { |
| 748 | size_t i; |
| 749 | const size_t count = lttng_dynamic_array_get_count( |
| 750 | &session->destroy_notifiers); |
| 751 | |
| 752 | for (i = 0; i < count; i++) { |
| 753 | const struct ltt_session_destroy_notifier_element *element = |
| 754 | lttng_dynamic_array_get_element( |
| 755 | &session->destroy_notifiers, i); |
| 756 | |
| 757 | element->notifier(session, element->user_data); |
| 758 | } |
| 759 | } |
| 760 | |
| 761 | static |
| 762 | void session_release(struct urcu_ref *ref) |
| 763 | { |
| 764 | int ret; |
| 765 | struct ltt_ust_session *usess; |
| 766 | struct ltt_kernel_session *ksess; |
| 767 | struct ltt_session *session = container_of(ref, typeof(*session), ref); |
| 768 | |
| 769 | assert(!session->chunk_being_archived); |
| 770 | |
| 771 | usess = session->ust_session; |
| 772 | ksess = session->kernel_session; |
| 773 | |
| 774 | session_notify_destruction(session); |
| 775 | lttng_dynamic_array_reset(&session->destroy_notifiers, NULL); |
| 776 | if (session->current_trace_chunk) { |
| 777 | ret = session_close_trace_chunk(session, session->current_trace_chunk); |
| 778 | if (ret) { |
| 779 | ERR("Failed to close the current trace chunk of session \"%s\" during its release", |
| 780 | session->name); |
| 781 | } |
| 782 | ret = _session_set_trace_chunk_no_lock_check(session, NULL, NULL); |
| 783 | if (ret) { |
| 784 | ERR("Failed to release the current trace chunk of session \"%s\" during its release", |
| 785 | session->name); |
| 786 | } |
| 787 | } |
| 788 | |
| 789 | /* Clean kernel session teardown */ |
| 790 | kernel_destroy_session(ksess); |
| 791 | session->kernel_session = NULL; |
| 792 | |
| 793 | /* UST session teardown */ |
| 794 | if (usess) { |
| 795 | /* Close any relayd session */ |
| 796 | consumer_output_send_destroy_relayd(usess->consumer); |
| 797 | |
| 798 | /* Destroy every UST application related to this session. */ |
| 799 | ret = ust_app_destroy_trace_all(usess); |
| 800 | if (ret) { |
| 801 | ERR("Error in ust_app_destroy_trace_all"); |
| 802 | } |
| 803 | |
| 804 | /* Clean up the rest. */ |
| 805 | trace_ust_destroy_session(usess); |
| 806 | session->ust_session = NULL; |
| 807 | } |
| 808 | |
| 809 | /* |
| 810 | * Must notify the kernel thread here to update it's poll set in order to |
| 811 | * remove the channel(s)' fd just destroyed. |
| 812 | */ |
| 813 | ret = notify_thread_pipe(kernel_poll_pipe[1]); |
| 814 | if (ret < 0) { |
| 815 | PERROR("write kernel poll pipe"); |
| 816 | } |
| 817 | |
| 818 | DBG("Destroying session %s (id %" PRIu64 ")", session->name, session->id); |
| 819 | |
| 820 | consumer_output_put(session->consumer); |
| 821 | snapshot_destroy(&session->snapshot); |
| 822 | |
| 823 | pthread_mutex_destroy(&session->lock); |
| 824 | |
| 825 | if (session->published) { |
| 826 | ASSERT_LOCKED(ltt_session_list.lock); |
| 827 | del_session_list(session); |
| 828 | del_session_ht(session); |
| 829 | pthread_cond_broadcast(<t_session_list.removal_cond); |
| 830 | } |
| 831 | free(session->last_archived_chunk_name); |
| 832 | free(session); |
| 833 | } |
| 834 | |
| 835 | /* |
| 836 | * Acquire a reference to a session. |
| 837 | * This function may fail (return false); its return value must be checked. |
| 838 | */ |
| 839 | bool session_get(struct ltt_session *session) |
| 840 | { |
| 841 | return urcu_ref_get_unless_zero(&session->ref); |
| 842 | } |
| 843 | |
| 844 | /* |
| 845 | * Release a reference to a session. |
| 846 | */ |
| 847 | void session_put(struct ltt_session *session) |
| 848 | { |
| 849 | if (!session) { |
| 850 | return; |
| 851 | } |
| 852 | /* |
| 853 | * The session list lock must be held as any session_put() |
| 854 | * may cause the removal of the session from the session_list. |
| 855 | */ |
| 856 | ASSERT_LOCKED(ltt_session_list.lock); |
| 857 | assert(session->ref.refcount); |
| 858 | urcu_ref_put(&session->ref, session_release); |
| 859 | } |
| 860 | |
| 861 | /* |
| 862 | * Destroy a session. |
| 863 | * |
| 864 | * This method does not immediately release/free the session as other |
| 865 | * components may still hold a reference to the session. However, |
| 866 | * the session should no longer be presented to the user. |
| 867 | * |
| 868 | * Releases the session list's reference to the session |
| 869 | * and marks it as destroyed. Iterations on the session list should be |
| 870 | * mindful of the "destroyed" flag. |
| 871 | */ |
| 872 | void session_destroy(struct ltt_session *session) |
| 873 | { |
| 874 | assert(!session->destroyed); |
| 875 | session->destroyed = true; |
| 876 | session_put(session); |
| 877 | } |
| 878 | |
| 879 | int session_add_destroy_notifier(struct ltt_session *session, |
| 880 | ltt_session_destroy_notifier notifier, void *user_data) |
| 881 | { |
| 882 | const struct ltt_session_destroy_notifier_element element = { |
| 883 | .notifier = notifier, |
| 884 | .user_data = user_data |
| 885 | }; |
| 886 | |
| 887 | return lttng_dynamic_array_add_element(&session->destroy_notifiers, |
| 888 | &element); |
| 889 | } |
| 890 | |
| 891 | /* |
| 892 | * Return a ltt_session structure ptr that matches name. If no session found, |
| 893 | * NULL is returned. This must be called with the session list lock held using |
| 894 | * session_lock_list and session_unlock_list. |
| 895 | * A reference to the session is implicitly acquired by this function. |
| 896 | */ |
| 897 | struct ltt_session *session_find_by_name(const char *name) |
| 898 | { |
| 899 | struct ltt_session *iter; |
| 900 | |
| 901 | assert(name); |
| 902 | ASSERT_LOCKED(ltt_session_list.lock); |
| 903 | |
| 904 | DBG2("Trying to find session by name %s", name); |
| 905 | |
| 906 | cds_list_for_each_entry(iter, <t_session_list.head, list) { |
| 907 | if (!strncmp(iter->name, name, NAME_MAX) && |
| 908 | !iter->destroyed) { |
| 909 | goto found; |
| 910 | } |
| 911 | } |
| 912 | |
| 913 | return NULL; |
| 914 | found: |
| 915 | return session_get(iter) ? iter : NULL; |
| 916 | } |
| 917 | |
| 918 | /* |
| 919 | * Return an ltt_session that matches the id. If no session is found, |
| 920 | * NULL is returned. This must be called with rcu_read_lock and |
| 921 | * session list lock held (to guarantee the lifetime of the session). |
| 922 | */ |
| 923 | struct ltt_session *session_find_by_id(uint64_t id) |
| 924 | { |
| 925 | struct lttng_ht_node_u64 *node; |
| 926 | struct lttng_ht_iter iter; |
| 927 | struct ltt_session *ls; |
| 928 | |
| 929 | ASSERT_LOCKED(ltt_session_list.lock); |
| 930 | |
| 931 | if (!ltt_sessions_ht_by_id) { |
| 932 | goto end; |
| 933 | } |
| 934 | |
| 935 | lttng_ht_lookup(ltt_sessions_ht_by_id, &id, &iter); |
| 936 | node = lttng_ht_iter_get_node_u64(&iter); |
| 937 | if (node == NULL) { |
| 938 | goto end; |
| 939 | } |
| 940 | ls = caa_container_of(node, struct ltt_session, node); |
| 941 | |
| 942 | DBG3("Session %" PRIu64 " found by id.", id); |
| 943 | return session_get(ls) ? ls : NULL; |
| 944 | |
| 945 | end: |
| 946 | DBG3("Session %" PRIu64 " NOT found by id", id); |
| 947 | return NULL; |
| 948 | } |
| 949 | |
| 950 | /* |
| 951 | * Create a new session and add it to the session list. |
| 952 | * Session list lock must be held by the caller. |
| 953 | */ |
| 954 | enum lttng_error_code session_create(const char *name, uid_t uid, gid_t gid, |
| 955 | struct ltt_session **out_session) |
| 956 | { |
| 957 | int ret; |
| 958 | enum lttng_error_code ret_code; |
| 959 | struct ltt_session *new_session = NULL; |
| 960 | |
| 961 | ASSERT_LOCKED(ltt_session_list.lock); |
| 962 | if (name) { |
| 963 | struct ltt_session *clashing_session; |
| 964 | |
| 965 | clashing_session = session_find_by_name(name); |
| 966 | if (clashing_session) { |
| 967 | session_put(clashing_session); |
| 968 | ret_code = LTTNG_ERR_EXIST_SESS; |
| 969 | goto error; |
| 970 | } |
| 971 | } |
| 972 | new_session = zmalloc(sizeof(struct ltt_session)); |
| 973 | if (!new_session) { |
| 974 | PERROR("Failed to allocate an ltt_session structure"); |
| 975 | ret_code = LTTNG_ERR_NOMEM; |
| 976 | goto error; |
| 977 | } |
| 978 | |
| 979 | lttng_dynamic_array_init(&new_session->destroy_notifiers, |
| 980 | sizeof(struct ltt_session_destroy_notifier_element)); |
| 981 | urcu_ref_init(&new_session->ref); |
| 982 | pthread_mutex_init(&new_session->lock, NULL); |
| 983 | |
| 984 | new_session->creation_time = time(NULL); |
| 985 | if (new_session->creation_time == (time_t) -1) { |
| 986 | PERROR("Failed to sample session creation time"); |
| 987 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 988 | goto error; |
| 989 | } |
| 990 | |
| 991 | /* Create default consumer output. */ |
| 992 | new_session->consumer = consumer_create_output(CONSUMER_DST_LOCAL); |
| 993 | if (new_session->consumer == NULL) { |
| 994 | ret_code = LTTNG_ERR_NOMEM; |
| 995 | goto error; |
| 996 | } |
| 997 | |
| 998 | if (name) { |
| 999 | ret = lttng_strncpy(new_session->name, name, sizeof(new_session->name)); |
| 1000 | if (ret) { |
| 1001 | ret_code = LTTNG_ERR_SESSION_INVALID_CHAR; |
| 1002 | goto error; |
| 1003 | } |
| 1004 | ret = validate_name(name); |
| 1005 | if (ret < 0) { |
| 1006 | ret_code = LTTNG_ERR_SESSION_INVALID_CHAR; |
| 1007 | goto error; |
| 1008 | } |
| 1009 | } else { |
| 1010 | int i = 0; |
| 1011 | bool found_name = false; |
| 1012 | char datetime[16]; |
| 1013 | struct tm *timeinfo; |
| 1014 | |
| 1015 | timeinfo = localtime(&new_session->creation_time); |
| 1016 | if (!timeinfo) { |
| 1017 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1018 | goto error; |
| 1019 | } |
| 1020 | strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo); |
| 1021 | for (i = 0; i < INT_MAX; i++) { |
| 1022 | struct ltt_session *clashing_session; |
| 1023 | |
| 1024 | if (i == 0) { |
| 1025 | ret = snprintf(new_session->name, |
| 1026 | sizeof(new_session->name), |
| 1027 | "%s-%s", |
| 1028 | DEFAULT_SESSION_NAME, |
| 1029 | datetime); |
| 1030 | } else { |
| 1031 | ret = snprintf(new_session->name, |
| 1032 | sizeof(new_session->name), |
| 1033 | "%s%d-%s", |
| 1034 | DEFAULT_SESSION_NAME, i, |
| 1035 | datetime); |
| 1036 | } |
| 1037 | if (ret == -1 || ret >= sizeof(new_session->name)) { |
| 1038 | /* |
| 1039 | * Null-terminate in case the name is used |
| 1040 | * in logging statements. |
| 1041 | */ |
| 1042 | new_session->name[sizeof(new_session->name) - 1] = '\0'; |
| 1043 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1044 | goto error; |
| 1045 | } |
| 1046 | |
| 1047 | clashing_session = |
| 1048 | session_find_by_name(new_session->name); |
| 1049 | session_put(clashing_session); |
| 1050 | if (!clashing_session) { |
| 1051 | found_name = true; |
| 1052 | break; |
| 1053 | } |
| 1054 | } |
| 1055 | if (found_name) { |
| 1056 | DBG("Generated session name \"%s\"", new_session->name); |
| 1057 | new_session->has_auto_generated_name = true; |
| 1058 | } else { |
| 1059 | ERR("Failed to auto-generate a session name"); |
| 1060 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1061 | goto error; |
| 1062 | } |
| 1063 | } |
| 1064 | |
| 1065 | ret = gethostname(new_session->hostname, sizeof(new_session->hostname)); |
| 1066 | if (ret < 0) { |
| 1067 | if (errno == ENAMETOOLONG) { |
| 1068 | new_session->hostname[sizeof(new_session->hostname) - 1] = '\0'; |
| 1069 | ERR("Hostname exceeds the maximal permitted length and has been truncated to %s", |
| 1070 | new_session->hostname); |
| 1071 | } else { |
| 1072 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1073 | goto error; |
| 1074 | } |
| 1075 | } |
| 1076 | |
| 1077 | new_session->uid = uid; |
| 1078 | new_session->gid = gid; |
| 1079 | |
| 1080 | ret = snapshot_init(&new_session->snapshot); |
| 1081 | if (ret < 0) { |
| 1082 | ret_code = LTTNG_ERR_NOMEM; |
| 1083 | goto error; |
| 1084 | } |
| 1085 | |
| 1086 | new_session->rotation_state = LTTNG_ROTATION_STATE_NO_ROTATION; |
| 1087 | |
| 1088 | /* Add new session to the session list. */ |
| 1089 | new_session->id = add_session_list(new_session); |
| 1090 | |
| 1091 | /* |
| 1092 | * Add the new session to the ltt_sessions_ht_by_id. |
| 1093 | * No ownership is taken by the hash table; it is merely |
| 1094 | * a wrapper around the session list used for faster access |
| 1095 | * by session id. |
| 1096 | */ |
| 1097 | add_session_ht(new_session); |
| 1098 | new_session->published = true; |
| 1099 | |
| 1100 | /* |
| 1101 | * Consumer is left to NULL since the create_session_uri command will |
| 1102 | * set it up and, if valid, assign it to the session. |
| 1103 | */ |
| 1104 | DBG("Tracing session %s created with ID %" PRIu64 " by uid = %d, gid = %d", |
| 1105 | new_session->name, new_session->id, new_session->uid, |
| 1106 | new_session->gid); |
| 1107 | ret_code = LTTNG_OK; |
| 1108 | end: |
| 1109 | if (new_session) { |
| 1110 | (void) session_get(new_session); |
| 1111 | *out_session = new_session; |
| 1112 | } |
| 1113 | return ret_code; |
| 1114 | error: |
| 1115 | session_put(new_session); |
| 1116 | new_session = NULL; |
| 1117 | goto end; |
| 1118 | } |
| 1119 | |
| 1120 | /* |
| 1121 | * Check if the UID or GID match the session. Root user has access to all |
| 1122 | * sessions. |
| 1123 | */ |
| 1124 | int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid) |
| 1125 | { |
| 1126 | assert(session); |
| 1127 | |
| 1128 | if (uid != session->uid && gid != session->gid && uid != 0) { |
| 1129 | return 0; |
| 1130 | } else { |
| 1131 | return 1; |
| 1132 | } |
| 1133 | } |
| 1134 | |
| 1135 | /* |
| 1136 | * Set a session's rotation state and reset all associated state. |
| 1137 | * |
| 1138 | * This function resets the rotation state (check timers, pending |
| 1139 | * flags, etc.) and sets the result of the last rotation. The result |
| 1140 | * can be queries by a liblttng-ctl client. |
| 1141 | * |
| 1142 | * Be careful of the result passed to this function. For instance, |
| 1143 | * on failure to launch a rotation, a client will expect the rotation |
| 1144 | * state to be set to "NO_ROTATION". If an error occured while the |
| 1145 | * rotation was "ONGOING", result should be set to "ERROR", which will |
| 1146 | * allow a client to report it. |
| 1147 | * |
| 1148 | * Must be called with the session and session_list locks held. |
| 1149 | */ |
| 1150 | int session_reset_rotation_state(struct ltt_session *session, |
| 1151 | enum lttng_rotation_state result) |
| 1152 | { |
| 1153 | int ret = 0; |
| 1154 | |
| 1155 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1156 | ASSERT_LOCKED(session->lock); |
| 1157 | |
| 1158 | session->rotation_state = result; |
| 1159 | if (session->rotation_pending_check_timer_enabled) { |
| 1160 | ret = timer_session_rotation_pending_check_stop(session); |
| 1161 | } |
| 1162 | if (session->chunk_being_archived) { |
| 1163 | uint64_t chunk_id; |
| 1164 | enum lttng_trace_chunk_status chunk_status; |
| 1165 | |
| 1166 | chunk_status = lttng_trace_chunk_get_id( |
| 1167 | session->chunk_being_archived, |
| 1168 | &chunk_id); |
| 1169 | assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK); |
| 1170 | LTTNG_OPTIONAL_SET(&session->last_archived_chunk_id, |
| 1171 | chunk_id); |
| 1172 | lttng_trace_chunk_put(session->chunk_being_archived); |
| 1173 | session->chunk_being_archived = NULL; |
| 1174 | } |
| 1175 | return ret; |
| 1176 | } |