| 1 | /* |
| 2 | * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca> |
| 3 | * |
| 4 | * SPDX-License-Identifier: GPL-2.0-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #define _LGPL_SOURCE |
| 9 | #include <limits.h> |
| 10 | #include <inttypes.h> |
| 11 | #include <stdio.h> |
| 12 | #include <stdlib.h> |
| 13 | #include <string.h> |
| 14 | #include <sys/stat.h> |
| 15 | #include <urcu.h> |
| 16 | #include <dirent.h> |
| 17 | #include <sys/types.h> |
| 18 | #include <pthread.h> |
| 19 | |
| 20 | #include <common/common.h> |
| 21 | #include <common/utils.h> |
| 22 | #include <common/trace-chunk.h> |
| 23 | #include <common/sessiond-comm/sessiond-comm.h> |
| 24 | #include <lttng/location-internal.h> |
| 25 | #include "lttng-sessiond.h" |
| 26 | #include "kernel.h" |
| 27 | |
| 28 | #include "session.h" |
| 29 | #include "utils.h" |
| 30 | #include "trace-ust.h" |
| 31 | #include "timer.h" |
| 32 | #include "cmd.h" |
| 33 | |
| 34 | struct ltt_session_destroy_notifier_element { |
| 35 | ltt_session_destroy_notifier notifier; |
| 36 | void *user_data; |
| 37 | }; |
| 38 | |
| 39 | struct ltt_session_clear_notifier_element { |
| 40 | ltt_session_clear_notifier notifier; |
| 41 | void *user_data; |
| 42 | }; |
| 43 | |
| 44 | /* |
| 45 | * NOTES: |
| 46 | * |
| 47 | * No ltt_session.lock is taken here because those data structure are widely |
| 48 | * spread across the lttng-tools code base so before calling functions below |
| 49 | * that can read/write a session, the caller MUST acquire the session lock |
| 50 | * using session_lock() and session_unlock(). |
| 51 | */ |
| 52 | |
| 53 | /* |
| 54 | * Init tracing session list. |
| 55 | * |
| 56 | * Please see session.h for more explanation and correct usage of the list. |
| 57 | */ |
| 58 | static struct ltt_session_list ltt_session_list = { |
| 59 | .head = CDS_LIST_HEAD_INIT(ltt_session_list.head), |
| 60 | .lock = PTHREAD_MUTEX_INITIALIZER, |
| 61 | .removal_cond = PTHREAD_COND_INITIALIZER, |
| 62 | .next_uuid = 0, |
| 63 | }; |
| 64 | |
| 65 | /* These characters are forbidden in a session name. Used by validate_name. */ |
| 66 | static const char *forbidden_name_chars = "/"; |
| 67 | |
| 68 | /* Global hash table to keep the sessions, indexed by id. */ |
| 69 | static struct lttng_ht *ltt_sessions_ht_by_id = NULL; |
| 70 | /* Global hash table to keep the sessions, indexed by name. */ |
| 71 | static struct lttng_ht *ltt_sessions_ht_by_name = NULL; |
| 72 | |
| 73 | /* |
| 74 | * Validate the session name for forbidden characters. |
| 75 | * |
| 76 | * Return 0 on success else -1 meaning a forbidden char. has been found. |
| 77 | */ |
| 78 | static int validate_name(const char *name) |
| 79 | { |
| 80 | int ret; |
| 81 | char *tok, *tmp_name; |
| 82 | |
| 83 | assert(name); |
| 84 | |
| 85 | tmp_name = strdup(name); |
| 86 | if (!tmp_name) { |
| 87 | /* ENOMEM here. */ |
| 88 | ret = -1; |
| 89 | goto error; |
| 90 | } |
| 91 | |
| 92 | tok = strpbrk(tmp_name, forbidden_name_chars); |
| 93 | if (tok) { |
| 94 | DBG("Session name %s contains a forbidden character", name); |
| 95 | /* Forbidden character has been found. */ |
| 96 | ret = -1; |
| 97 | goto error; |
| 98 | } |
| 99 | ret = 0; |
| 100 | |
| 101 | error: |
| 102 | free(tmp_name); |
| 103 | return ret; |
| 104 | } |
| 105 | |
| 106 | /* |
| 107 | * Add a ltt_session structure to the global list. |
| 108 | * |
| 109 | * The caller MUST acquire the session list lock before. |
| 110 | * Returns the unique identifier for the session. |
| 111 | */ |
| 112 | static uint64_t add_session_list(struct ltt_session *ls) |
| 113 | { |
| 114 | assert(ls); |
| 115 | |
| 116 | cds_list_add(&ls->list, <t_session_list.head); |
| 117 | return ltt_session_list.next_uuid++; |
| 118 | } |
| 119 | |
| 120 | /* |
| 121 | * Delete a ltt_session structure to the global list. |
| 122 | * |
| 123 | * The caller MUST acquire the session list lock before. |
| 124 | */ |
| 125 | static void del_session_list(struct ltt_session *ls) |
| 126 | { |
| 127 | assert(ls); |
| 128 | |
| 129 | cds_list_del(&ls->list); |
| 130 | } |
| 131 | |
| 132 | /* |
| 133 | * Return a pointer to the session list. |
| 134 | */ |
| 135 | struct ltt_session_list *session_get_list(void) |
| 136 | { |
| 137 | return <t_session_list; |
| 138 | } |
| 139 | |
| 140 | /* |
| 141 | * Returns once the session list is empty. |
| 142 | */ |
| 143 | void session_list_wait_empty(void) |
| 144 | { |
| 145 | pthread_mutex_lock(<t_session_list.lock); |
| 146 | while (!cds_list_empty(<t_session_list.head)) { |
| 147 | pthread_cond_wait(<t_session_list.removal_cond, |
| 148 | <t_session_list.lock); |
| 149 | } |
| 150 | pthread_mutex_unlock(<t_session_list.lock); |
| 151 | } |
| 152 | |
| 153 | /* |
| 154 | * Acquire session list lock |
| 155 | */ |
| 156 | void session_lock_list(void) |
| 157 | { |
| 158 | pthread_mutex_lock(<t_session_list.lock); |
| 159 | } |
| 160 | |
| 161 | /* |
| 162 | * Try to acquire session list lock |
| 163 | */ |
| 164 | int session_trylock_list(void) |
| 165 | { |
| 166 | return pthread_mutex_trylock(<t_session_list.lock); |
| 167 | } |
| 168 | |
| 169 | /* |
| 170 | * Release session list lock |
| 171 | */ |
| 172 | void session_unlock_list(void) |
| 173 | { |
| 174 | pthread_mutex_unlock(<t_session_list.lock); |
| 175 | } |
| 176 | |
| 177 | /* |
| 178 | * Get the session's consumer destination type. |
| 179 | * |
| 180 | * The caller must hold the session lock. |
| 181 | */ |
| 182 | enum consumer_dst_type session_get_consumer_destination_type( |
| 183 | const struct ltt_session *session) |
| 184 | { |
| 185 | /* |
| 186 | * The output information is duplicated in both of those session types. |
| 187 | * Hence, it doesn't matter from which it is retrieved. However, it is |
| 188 | * possible for only one of them to be set. |
| 189 | */ |
| 190 | return session->kernel_session ? |
| 191 | session->kernel_session->consumer->type : |
| 192 | session->ust_session->consumer->type; |
| 193 | } |
| 194 | |
| 195 | /* |
| 196 | * Get the session's consumer network hostname. |
| 197 | * The caller must ensure that the destination is of type "net". |
| 198 | * |
| 199 | * The caller must hold the session lock. |
| 200 | */ |
| 201 | const char *session_get_net_consumer_hostname(const struct ltt_session *session) |
| 202 | { |
| 203 | const char *hostname = NULL; |
| 204 | const struct consumer_output *output; |
| 205 | |
| 206 | output = session->kernel_session ? |
| 207 | session->kernel_session->consumer : |
| 208 | session->ust_session->consumer; |
| 209 | |
| 210 | /* |
| 211 | * hostname is assumed to be the same for both control and data |
| 212 | * connections. |
| 213 | */ |
| 214 | switch (output->dst.net.control.dtype) { |
| 215 | case LTTNG_DST_IPV4: |
| 216 | hostname = output->dst.net.control.dst.ipv4; |
| 217 | break; |
| 218 | case LTTNG_DST_IPV6: |
| 219 | hostname = output->dst.net.control.dst.ipv6; |
| 220 | break; |
| 221 | default: |
| 222 | abort(); |
| 223 | } |
| 224 | return hostname; |
| 225 | } |
| 226 | |
| 227 | /* |
| 228 | * Get the session's consumer network control and data ports. |
| 229 | * The caller must ensure that the destination is of type "net". |
| 230 | * |
| 231 | * The caller must hold the session lock. |
| 232 | */ |
| 233 | void session_get_net_consumer_ports(const struct ltt_session *session, |
| 234 | uint16_t *control_port, uint16_t *data_port) |
| 235 | { |
| 236 | const struct consumer_output *output; |
| 237 | |
| 238 | output = session->kernel_session ? |
| 239 | session->kernel_session->consumer : |
| 240 | session->ust_session->consumer; |
| 241 | *control_port = output->dst.net.control.port; |
| 242 | *data_port = output->dst.net.data.port; |
| 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Get the location of the latest trace archive produced by a rotation. |
| 247 | * |
| 248 | * The caller must hold the session lock. |
| 249 | */ |
| 250 | struct lttng_trace_archive_location *session_get_trace_archive_location( |
| 251 | const struct ltt_session *session) |
| 252 | { |
| 253 | int ret; |
| 254 | struct lttng_trace_archive_location *location = NULL; |
| 255 | char *chunk_path = NULL; |
| 256 | |
| 257 | if (session->rotation_state != LTTNG_ROTATION_STATE_COMPLETED || |
| 258 | !session->last_archived_chunk_name) { |
| 259 | goto end; |
| 260 | } |
| 261 | |
| 262 | switch (session_get_consumer_destination_type(session)) { |
| 263 | case CONSUMER_DST_LOCAL: |
| 264 | ret = asprintf(&chunk_path, |
| 265 | "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY "/%s", |
| 266 | session_get_base_path(session), |
| 267 | session->last_archived_chunk_name); |
| 268 | if (ret == -1) { |
| 269 | goto end; |
| 270 | } |
| 271 | location = lttng_trace_archive_location_local_create( |
| 272 | chunk_path); |
| 273 | break; |
| 274 | case CONSUMER_DST_NET: |
| 275 | { |
| 276 | const char *hostname; |
| 277 | uint16_t control_port, data_port; |
| 278 | |
| 279 | hostname = session_get_net_consumer_hostname(session); |
| 280 | session_get_net_consumer_ports(session, |
| 281 | &control_port, |
| 282 | &data_port); |
| 283 | location = lttng_trace_archive_location_relay_create( |
| 284 | hostname, |
| 285 | LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP, |
| 286 | control_port, data_port, session->last_chunk_path); |
| 287 | break; |
| 288 | } |
| 289 | default: |
| 290 | abort(); |
| 291 | } |
| 292 | end: |
| 293 | free(chunk_path); |
| 294 | return location; |
| 295 | } |
| 296 | |
| 297 | /* |
| 298 | * Allocate the ltt_sessions_ht_by_id and ltt_sessions_ht_by_name HT. |
| 299 | * |
| 300 | * The session list lock must be held. |
| 301 | */ |
| 302 | static int ltt_sessions_ht_alloc(void) |
| 303 | { |
| 304 | int ret = 0; |
| 305 | |
| 306 | DBG("Allocating ltt_sessions_ht_by_id"); |
| 307 | ltt_sessions_ht_by_id = lttng_ht_new(0, LTTNG_HT_TYPE_U64); |
| 308 | if (!ltt_sessions_ht_by_id) { |
| 309 | ret = -1; |
| 310 | ERR("Failed to allocate ltt_sessions_ht_by_id"); |
| 311 | goto end; |
| 312 | } |
| 313 | |
| 314 | DBG("Allocating ltt_sessions_ht_by_name"); |
| 315 | ltt_sessions_ht_by_name = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); |
| 316 | if (!ltt_sessions_ht_by_name) { |
| 317 | ret = -1; |
| 318 | ERR("Failed to allocate ltt_sessions_ht_by_name"); |
| 319 | goto end; |
| 320 | } |
| 321 | |
| 322 | end: |
| 323 | return ret; |
| 324 | } |
| 325 | |
| 326 | /* |
| 327 | * Destroy the ltt_sessions_ht_by_id HT. |
| 328 | * |
| 329 | * The session list lock must be held. |
| 330 | */ |
| 331 | static void ltt_sessions_ht_destroy(void) |
| 332 | { |
| 333 | if (ltt_sessions_ht_by_id) { |
| 334 | ht_cleanup_push(ltt_sessions_ht_by_id); |
| 335 | ltt_sessions_ht_by_id = NULL; |
| 336 | } |
| 337 | |
| 338 | if (ltt_sessions_ht_by_name) { |
| 339 | ht_cleanup_push(ltt_sessions_ht_by_name); |
| 340 | ltt_sessions_ht_by_name = NULL; |
| 341 | } |
| 342 | |
| 343 | return; |
| 344 | } |
| 345 | |
| 346 | /* |
| 347 | * Add a ltt_session to the ltt_sessions_ht_by_id and ltt_sessions_ht_by_name. |
| 348 | * If unallocated, the ltt_sessions_ht_by_id and ltt_sessions_ht_by_name. HTs |
| 349 | * are allocated. The session list lock must be held. |
| 350 | */ |
| 351 | static void add_session_ht(struct ltt_session *ls) |
| 352 | { |
| 353 | int ret; |
| 354 | |
| 355 | assert(ls); |
| 356 | |
| 357 | if (!ltt_sessions_ht_by_id) { |
| 358 | ret = ltt_sessions_ht_alloc(); |
| 359 | if (ret) { |
| 360 | ERR("Error allocating the sessions HT"); |
| 361 | goto end; |
| 362 | } |
| 363 | } |
| 364 | |
| 365 | /* Should always be present with ltt_sessions_ht_by_id. */ |
| 366 | assert(ltt_sessions_ht_by_name); |
| 367 | |
| 368 | lttng_ht_node_init_u64(&ls->node, ls->id); |
| 369 | lttng_ht_add_unique_u64(ltt_sessions_ht_by_id, &ls->node); |
| 370 | |
| 371 | lttng_ht_node_init_str(&ls->node_by_name, ls->name); |
| 372 | lttng_ht_add_unique_str(ltt_sessions_ht_by_name, &ls->node_by_name); |
| 373 | |
| 374 | end: |
| 375 | return; |
| 376 | } |
| 377 | |
| 378 | /* |
| 379 | * Test if ltt_sessions_ht_by_id/name are empty. |
| 380 | * Return 1 if empty, 0 if not empty. |
| 381 | * The session list lock must be held. |
| 382 | */ |
| 383 | static int ltt_sessions_ht_empty(void) |
| 384 | { |
| 385 | unsigned long count; |
| 386 | |
| 387 | if (!ltt_sessions_ht_by_id) { |
| 388 | count = 0; |
| 389 | goto end; |
| 390 | } |
| 391 | |
| 392 | assert(ltt_sessions_ht_by_name); |
| 393 | |
| 394 | count = lttng_ht_get_count(ltt_sessions_ht_by_id); |
| 395 | assert(count == lttng_ht_get_count(ltt_sessions_ht_by_name)); |
| 396 | end: |
| 397 | return count ? 0 : 1; |
| 398 | } |
| 399 | |
| 400 | /* |
| 401 | * Remove a ltt_session from the ltt_sessions_ht_by_id/name. |
| 402 | * If empty, the ltt_sessions_ht_by_id/name HTs are freed. |
| 403 | * The session list lock must be held. |
| 404 | */ |
| 405 | static void del_session_ht(struct ltt_session *ls) |
| 406 | { |
| 407 | struct lttng_ht_iter iter; |
| 408 | int ret; |
| 409 | |
| 410 | assert(ls); |
| 411 | assert(ltt_sessions_ht_by_id); |
| 412 | assert(ltt_sessions_ht_by_name); |
| 413 | |
| 414 | iter.iter.node = &ls->node.node; |
| 415 | ret = lttng_ht_del(ltt_sessions_ht_by_id, &iter); |
| 416 | assert(!ret); |
| 417 | |
| 418 | iter.iter.node = &ls->node_by_name.node; |
| 419 | ret = lttng_ht_del(ltt_sessions_ht_by_name, &iter); |
| 420 | assert(!ret); |
| 421 | |
| 422 | if (ltt_sessions_ht_empty()) { |
| 423 | DBG("Empty ltt_sessions_ht_by_id/name, destroying hast tables"); |
| 424 | ltt_sessions_ht_destroy(); |
| 425 | } |
| 426 | } |
| 427 | |
| 428 | /* |
| 429 | * Acquire session lock |
| 430 | */ |
| 431 | void session_lock(struct ltt_session *session) |
| 432 | { |
| 433 | assert(session); |
| 434 | |
| 435 | pthread_mutex_lock(&session->lock); |
| 436 | } |
| 437 | |
| 438 | /* |
| 439 | * Release session lock |
| 440 | */ |
| 441 | void session_unlock(struct ltt_session *session) |
| 442 | { |
| 443 | assert(session); |
| 444 | |
| 445 | pthread_mutex_unlock(&session->lock); |
| 446 | } |
| 447 | |
| 448 | static |
| 449 | int _session_set_trace_chunk_no_lock_check(struct ltt_session *session, |
| 450 | struct lttng_trace_chunk *new_trace_chunk, |
| 451 | struct lttng_trace_chunk **_current_trace_chunk) |
| 452 | { |
| 453 | int ret = 0; |
| 454 | unsigned int i, refs_to_acquire = 0, refs_acquired = 0, refs_to_release = 0; |
| 455 | struct cds_lfht_iter iter; |
| 456 | struct consumer_socket *socket; |
| 457 | struct lttng_trace_chunk *current_trace_chunk; |
| 458 | uint64_t chunk_id; |
| 459 | enum lttng_trace_chunk_status chunk_status; |
| 460 | |
| 461 | rcu_read_lock(); |
| 462 | /* |
| 463 | * Ownership of current trace chunk is transferred to |
| 464 | * `current_trace_chunk`. |
| 465 | */ |
| 466 | current_trace_chunk = session->current_trace_chunk; |
| 467 | session->current_trace_chunk = NULL; |
| 468 | if (session->ust_session) { |
| 469 | lttng_trace_chunk_put( |
| 470 | session->ust_session->current_trace_chunk); |
| 471 | session->ust_session->current_trace_chunk = NULL; |
| 472 | } |
| 473 | if (session->kernel_session) { |
| 474 | lttng_trace_chunk_put( |
| 475 | session->kernel_session->current_trace_chunk); |
| 476 | session->kernel_session->current_trace_chunk = NULL; |
| 477 | } |
| 478 | if (!new_trace_chunk) { |
| 479 | ret = 0; |
| 480 | goto end; |
| 481 | } |
| 482 | chunk_status = lttng_trace_chunk_get_id(new_trace_chunk, &chunk_id); |
| 483 | assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK); |
| 484 | |
| 485 | refs_to_acquire = 1; |
| 486 | refs_to_acquire += !!session->ust_session; |
| 487 | refs_to_acquire += !!session->kernel_session; |
| 488 | |
| 489 | for (refs_acquired = 0; refs_acquired < refs_to_acquire; |
| 490 | refs_acquired++) { |
| 491 | if (!lttng_trace_chunk_get(new_trace_chunk)) { |
| 492 | ERR("Failed to acquire reference to new trace chunk of session \"%s\"", |
| 493 | session->name); |
| 494 | goto error; |
| 495 | } |
| 496 | } |
| 497 | |
| 498 | if (session->ust_session) { |
| 499 | const uint64_t relayd_id = |
| 500 | session->ust_session->consumer->net_seq_index; |
| 501 | const bool is_local_trace = |
| 502 | session->ust_session->consumer->type == |
| 503 | CONSUMER_DST_LOCAL; |
| 504 | |
| 505 | session->ust_session->current_trace_chunk = new_trace_chunk; |
| 506 | if (is_local_trace) { |
| 507 | enum lttng_error_code ret_error_code; |
| 508 | |
| 509 | ret_error_code = ust_app_create_channel_subdirectories( |
| 510 | session->ust_session); |
| 511 | if (ret_error_code != LTTNG_OK) { |
| 512 | goto error; |
| 513 | } |
| 514 | } |
| 515 | cds_lfht_for_each_entry( |
| 516 | session->ust_session->consumer->socks->ht, |
| 517 | &iter, socket, node.node) { |
| 518 | pthread_mutex_lock(socket->lock); |
| 519 | ret = consumer_create_trace_chunk(socket, |
| 520 | relayd_id, |
| 521 | session->id, new_trace_chunk, |
| 522 | DEFAULT_UST_TRACE_DIR); |
| 523 | pthread_mutex_unlock(socket->lock); |
| 524 | if (ret) { |
| 525 | goto error; |
| 526 | } |
| 527 | } |
| 528 | } |
| 529 | if (session->kernel_session) { |
| 530 | const uint64_t relayd_id = |
| 531 | session->kernel_session->consumer->net_seq_index; |
| 532 | const bool is_local_trace = |
| 533 | session->kernel_session->consumer->type == |
| 534 | CONSUMER_DST_LOCAL; |
| 535 | |
| 536 | session->kernel_session->current_trace_chunk = new_trace_chunk; |
| 537 | if (is_local_trace) { |
| 538 | enum lttng_error_code ret_error_code; |
| 539 | |
| 540 | ret_error_code = kernel_create_channel_subdirectories( |
| 541 | session->kernel_session); |
| 542 | if (ret_error_code != LTTNG_OK) { |
| 543 | goto error; |
| 544 | } |
| 545 | } |
| 546 | cds_lfht_for_each_entry( |
| 547 | session->kernel_session->consumer->socks->ht, |
| 548 | &iter, socket, node.node) { |
| 549 | pthread_mutex_lock(socket->lock); |
| 550 | ret = consumer_create_trace_chunk(socket, |
| 551 | relayd_id, |
| 552 | session->id, new_trace_chunk, |
| 553 | DEFAULT_KERNEL_TRACE_DIR); |
| 554 | pthread_mutex_unlock(socket->lock); |
| 555 | if (ret) { |
| 556 | goto error; |
| 557 | } |
| 558 | } |
| 559 | } |
| 560 | |
| 561 | /* |
| 562 | * Update local current trace chunk state last, only if all remote |
| 563 | * creations succeeded. |
| 564 | */ |
| 565 | session->current_trace_chunk = new_trace_chunk; |
| 566 | LTTNG_OPTIONAL_SET(&session->most_recent_chunk_id, chunk_id); |
| 567 | end: |
| 568 | if (_current_trace_chunk) { |
| 569 | *_current_trace_chunk = current_trace_chunk; |
| 570 | current_trace_chunk = NULL; |
| 571 | } |
| 572 | end_no_move: |
| 573 | rcu_read_unlock(); |
| 574 | lttng_trace_chunk_put(current_trace_chunk); |
| 575 | return ret; |
| 576 | error: |
| 577 | if (session->ust_session) { |
| 578 | session->ust_session->current_trace_chunk = NULL; |
| 579 | } |
| 580 | if (session->kernel_session) { |
| 581 | session->kernel_session->current_trace_chunk = NULL; |
| 582 | } |
| 583 | /* |
| 584 | * Release references taken in the case where all references could not |
| 585 | * be acquired. |
| 586 | */ |
| 587 | refs_to_release = refs_to_acquire - refs_acquired; |
| 588 | for (i = 0; i < refs_to_release; i++) { |
| 589 | lttng_trace_chunk_put(new_trace_chunk); |
| 590 | } |
| 591 | ret = -1; |
| 592 | goto end_no_move; |
| 593 | } |
| 594 | |
| 595 | struct lttng_trace_chunk *session_create_new_trace_chunk( |
| 596 | const struct ltt_session *session, |
| 597 | const struct consumer_output *consumer_output_override, |
| 598 | const char *session_base_path_override, |
| 599 | const char *chunk_name_override) |
| 600 | { |
| 601 | int ret; |
| 602 | struct lttng_trace_chunk *trace_chunk = NULL; |
| 603 | enum lttng_trace_chunk_status chunk_status; |
| 604 | const time_t chunk_creation_ts = time(NULL); |
| 605 | bool is_local_trace; |
| 606 | const char *base_path; |
| 607 | struct lttng_directory_handle *session_output_directory = NULL; |
| 608 | const struct lttng_credentials session_credentials = { |
| 609 | .uid = LTTNG_OPTIONAL_INIT_VALUE(session->uid), |
| 610 | .gid = LTTNG_OPTIONAL_INIT_VALUE(session->gid), |
| 611 | }; |
| 612 | uint64_t next_chunk_id; |
| 613 | const struct consumer_output *output; |
| 614 | const char *new_path; |
| 615 | |
| 616 | if (consumer_output_override) { |
| 617 | output = consumer_output_override; |
| 618 | } else { |
| 619 | assert(session->ust_session || session->kernel_session); |
| 620 | output = session->ust_session ? |
| 621 | session->ust_session->consumer : |
| 622 | session->kernel_session->consumer; |
| 623 | } |
| 624 | |
| 625 | is_local_trace = output->type == CONSUMER_DST_LOCAL; |
| 626 | base_path = session_base_path_override ? : |
| 627 | consumer_output_get_base_path(output); |
| 628 | |
| 629 | if (chunk_creation_ts == (time_t) -1) { |
| 630 | PERROR("Failed to sample time while creation session \"%s\" trace chunk", |
| 631 | session->name); |
| 632 | goto error; |
| 633 | } |
| 634 | |
| 635 | next_chunk_id = session->most_recent_chunk_id.is_set ? |
| 636 | session->most_recent_chunk_id.value + 1 : 0; |
| 637 | |
| 638 | if (session->current_trace_chunk && |
| 639 | !lttng_trace_chunk_get_name_overridden(session->current_trace_chunk)) { |
| 640 | chunk_status = lttng_trace_chunk_rename_path(session->current_trace_chunk, |
| 641 | DEFAULT_CHUNK_TMP_OLD_DIRECTORY); |
| 642 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 643 | goto error; |
| 644 | } |
| 645 | } |
| 646 | if (!session->current_trace_chunk) { |
| 647 | if (!session->rotated) { |
| 648 | new_path = ""; |
| 649 | } else { |
| 650 | new_path = NULL; |
| 651 | } |
| 652 | } else { |
| 653 | new_path = DEFAULT_CHUNK_TMP_NEW_DIRECTORY; |
| 654 | } |
| 655 | |
| 656 | trace_chunk = lttng_trace_chunk_create(next_chunk_id, |
| 657 | chunk_creation_ts, new_path); |
| 658 | if (!trace_chunk) { |
| 659 | goto error; |
| 660 | } |
| 661 | |
| 662 | if (chunk_name_override) { |
| 663 | chunk_status = lttng_trace_chunk_override_name(trace_chunk, |
| 664 | chunk_name_override); |
| 665 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 666 | goto error; |
| 667 | } |
| 668 | } |
| 669 | |
| 670 | if (!is_local_trace) { |
| 671 | /* |
| 672 | * No need to set crendentials and output directory |
| 673 | * for remote trace chunks. |
| 674 | */ |
| 675 | goto end; |
| 676 | } |
| 677 | |
| 678 | chunk_status = lttng_trace_chunk_set_credentials(trace_chunk, |
| 679 | &session_credentials); |
| 680 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 681 | goto error; |
| 682 | } |
| 683 | |
| 684 | DBG("Creating base output directory of session \"%s\" at %s", |
| 685 | session->name, base_path); |
| 686 | ret = utils_mkdir_recursive(base_path, S_IRWXU | S_IRWXG, |
| 687 | session->uid, session->gid); |
| 688 | if (ret) { |
| 689 | goto error; |
| 690 | } |
| 691 | session_output_directory = lttng_directory_handle_create(base_path); |
| 692 | if (!session_output_directory) { |
| 693 | goto error; |
| 694 | } |
| 695 | chunk_status = lttng_trace_chunk_set_as_owner(trace_chunk, |
| 696 | session_output_directory); |
| 697 | lttng_directory_handle_put(session_output_directory); |
| 698 | session_output_directory = NULL; |
| 699 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 700 | goto error; |
| 701 | } |
| 702 | end: |
| 703 | return trace_chunk; |
| 704 | error: |
| 705 | lttng_directory_handle_put(session_output_directory); |
| 706 | lttng_trace_chunk_put(trace_chunk); |
| 707 | trace_chunk = NULL; |
| 708 | goto end; |
| 709 | } |
| 710 | |
| 711 | int session_close_trace_chunk(struct ltt_session *session, |
| 712 | struct lttng_trace_chunk *trace_chunk, |
| 713 | enum lttng_trace_chunk_command_type close_command, |
| 714 | char *closed_trace_chunk_path) |
| 715 | { |
| 716 | int ret = 0; |
| 717 | bool error_occurred = false; |
| 718 | struct cds_lfht_iter iter; |
| 719 | struct consumer_socket *socket; |
| 720 | enum lttng_trace_chunk_status chunk_status; |
| 721 | const time_t chunk_close_timestamp = time(NULL); |
| 722 | const char *new_path; |
| 723 | |
| 724 | chunk_status = lttng_trace_chunk_set_close_command( |
| 725 | trace_chunk, close_command); |
| 726 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 727 | ret = -1; |
| 728 | goto end; |
| 729 | } |
| 730 | |
| 731 | if (chunk_close_timestamp == (time_t) -1) { |
| 732 | ERR("Failed to sample the close timestamp of the current trace chunk of session \"%s\"", |
| 733 | session->name); |
| 734 | ret = -1; |
| 735 | goto end; |
| 736 | } |
| 737 | |
| 738 | if (close_command == LTTNG_TRACE_CHUNK_COMMAND_TYPE_DELETE && !session->rotated) { |
| 739 | /* New chunk stays in session output directory. */ |
| 740 | new_path = ""; |
| 741 | } else { |
| 742 | /* Use chunk name for new chunk. */ |
| 743 | new_path = NULL; |
| 744 | } |
| 745 | if (session->current_trace_chunk && |
| 746 | !lttng_trace_chunk_get_name_overridden(session->current_trace_chunk)) { |
| 747 | /* Rename new chunk path. */ |
| 748 | chunk_status = lttng_trace_chunk_rename_path(session->current_trace_chunk, |
| 749 | new_path); |
| 750 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 751 | ret = -1; |
| 752 | goto end; |
| 753 | } |
| 754 | } |
| 755 | if (!lttng_trace_chunk_get_name_overridden(trace_chunk) && |
| 756 | close_command == LTTNG_TRACE_CHUNK_COMMAND_TYPE_NO_OPERATION) { |
| 757 | const char *old_path; |
| 758 | |
| 759 | if (!session->rotated) { |
| 760 | old_path = ""; |
| 761 | } else { |
| 762 | old_path = NULL; |
| 763 | } |
| 764 | /* We need to move back the .tmp_old_chunk to its rightful place. */ |
| 765 | chunk_status = lttng_trace_chunk_rename_path(trace_chunk, |
| 766 | old_path); |
| 767 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 768 | ret = -1; |
| 769 | goto end; |
| 770 | } |
| 771 | } |
| 772 | if (close_command == LTTNG_TRACE_CHUNK_COMMAND_TYPE_MOVE_TO_COMPLETED) { |
| 773 | session->rotated = true; |
| 774 | } |
| 775 | chunk_status = lttng_trace_chunk_set_close_timestamp(trace_chunk, |
| 776 | chunk_close_timestamp); |
| 777 | if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) { |
| 778 | ERR("Failed to set the close timestamp of the current trace chunk of session \"%s\"", |
| 779 | session->name); |
| 780 | ret = -1; |
| 781 | goto end; |
| 782 | } |
| 783 | |
| 784 | if (session->ust_session) { |
| 785 | const uint64_t relayd_id = |
| 786 | session->ust_session->consumer->net_seq_index; |
| 787 | |
| 788 | cds_lfht_for_each_entry( |
| 789 | session->ust_session->consumer->socks->ht, |
| 790 | &iter, socket, node.node) { |
| 791 | pthread_mutex_lock(socket->lock); |
| 792 | ret = consumer_close_trace_chunk(socket, |
| 793 | relayd_id, |
| 794 | session->id, |
| 795 | trace_chunk, closed_trace_chunk_path); |
| 796 | pthread_mutex_unlock(socket->lock); |
| 797 | if (ret) { |
| 798 | ERR("Failed to close trace chunk on user space consumer"); |
| 799 | error_occurred = true; |
| 800 | } |
| 801 | } |
| 802 | } |
| 803 | if (session->kernel_session) { |
| 804 | const uint64_t relayd_id = |
| 805 | session->kernel_session->consumer->net_seq_index; |
| 806 | |
| 807 | cds_lfht_for_each_entry( |
| 808 | session->kernel_session->consumer->socks->ht, |
| 809 | &iter, socket, node.node) { |
| 810 | pthread_mutex_lock(socket->lock); |
| 811 | ret = consumer_close_trace_chunk(socket, |
| 812 | relayd_id, |
| 813 | session->id, |
| 814 | trace_chunk, closed_trace_chunk_path); |
| 815 | pthread_mutex_unlock(socket->lock); |
| 816 | if (ret) { |
| 817 | ERR("Failed to close trace chunk on kernel consumer"); |
| 818 | error_occurred = true; |
| 819 | } |
| 820 | } |
| 821 | } |
| 822 | ret = error_occurred ? -1 : 0; |
| 823 | end: |
| 824 | return ret; |
| 825 | } |
| 826 | |
| 827 | /* |
| 828 | * This function skips the metadata channel as the begin/end timestamps of a |
| 829 | * metadata packet are useless. |
| 830 | * |
| 831 | * Moreover, opening a packet after a "clear" will cause problems for live |
| 832 | * sessions as it will introduce padding that was not part of the first trace |
| 833 | * chunk. The relay daemon expects the content of the metadata stream of |
| 834 | * successive metadata trace chunks to be strict supersets of one another. |
| 835 | * |
| 836 | * For example, flushing a packet at the beginning of the metadata stream of |
| 837 | * a trace chunk resulting from a "clear" session command will cause the |
| 838 | * size of the metadata stream of the new trace chunk to not match the size of |
| 839 | * the metadata stream of the original chunk. This will confuse the relay |
| 840 | * daemon as the same "offset" in a metadata stream will no longer point |
| 841 | * to the same content. |
| 842 | */ |
| 843 | static |
| 844 | enum lttng_error_code session_kernel_open_packets(struct ltt_session *session) |
| 845 | { |
| 846 | enum lttng_error_code ret = LTTNG_OK; |
| 847 | struct consumer_socket *socket; |
| 848 | struct lttng_ht_iter iter; |
| 849 | struct cds_lfht_node *node; |
| 850 | struct ltt_kernel_channel *chan; |
| 851 | |
| 852 | rcu_read_lock(); |
| 853 | |
| 854 | cds_lfht_first(session->kernel_session->consumer->socks->ht, &iter.iter); |
| 855 | node = cds_lfht_iter_get_node(&iter.iter); |
| 856 | socket = container_of(node, typeof(*socket), node.node); |
| 857 | |
| 858 | cds_list_for_each_entry(chan, |
| 859 | &session->kernel_session->channel_list.head, list) { |
| 860 | int open_ret; |
| 861 | |
| 862 | DBG("Open packet of kernel channel: channel key = %" PRIu64 |
| 863 | ", session name = %s, session_id = %" PRIu64, |
| 864 | chan->key, session->name, session->id); |
| 865 | |
| 866 | open_ret = consumer_open_channel_packets(socket, chan->key); |
| 867 | if (open_ret < 0) { |
| 868 | /* General error (no known error expected). */ |
| 869 | ret = LTTNG_ERR_UNK; |
| 870 | goto end; |
| 871 | } |
| 872 | } |
| 873 | |
| 874 | end: |
| 875 | rcu_read_unlock(); |
| 876 | return ret; |
| 877 | } |
| 878 | |
| 879 | enum lttng_error_code session_open_packets(struct ltt_session *session) |
| 880 | { |
| 881 | enum lttng_error_code ret = LTTNG_OK; |
| 882 | |
| 883 | DBG("Opening packets of session channels: session name = %s, session id = %" PRIu64, |
| 884 | session->name, session->id); |
| 885 | |
| 886 | if (session->ust_session) { |
| 887 | ret = ust_app_open_packets(session); |
| 888 | if (ret != LTTNG_OK) { |
| 889 | goto end; |
| 890 | } |
| 891 | } |
| 892 | |
| 893 | if (session->kernel_session) { |
| 894 | ret = session_kernel_open_packets(session); |
| 895 | if (ret != LTTNG_OK) { |
| 896 | goto end; |
| 897 | } |
| 898 | } |
| 899 | |
| 900 | end: |
| 901 | return ret; |
| 902 | } |
| 903 | |
| 904 | /* |
| 905 | * Set a session's current trace chunk. |
| 906 | * |
| 907 | * Must be called with the session lock held. |
| 908 | */ |
| 909 | int session_set_trace_chunk(struct ltt_session *session, |
| 910 | struct lttng_trace_chunk *new_trace_chunk, |
| 911 | struct lttng_trace_chunk **current_trace_chunk) |
| 912 | { |
| 913 | ASSERT_LOCKED(session->lock); |
| 914 | return _session_set_trace_chunk_no_lock_check(session, new_trace_chunk, |
| 915 | current_trace_chunk); |
| 916 | } |
| 917 | |
| 918 | static |
| 919 | void session_notify_destruction(const struct ltt_session *session) |
| 920 | { |
| 921 | size_t i; |
| 922 | const size_t count = lttng_dynamic_array_get_count( |
| 923 | &session->destroy_notifiers); |
| 924 | |
| 925 | for (i = 0; i < count; i++) { |
| 926 | const struct ltt_session_destroy_notifier_element *element = |
| 927 | lttng_dynamic_array_get_element( |
| 928 | &session->destroy_notifiers, i); |
| 929 | |
| 930 | element->notifier(session, element->user_data); |
| 931 | } |
| 932 | } |
| 933 | |
| 934 | /* |
| 935 | * Fire each clear notifier once, and remove them from the array. |
| 936 | */ |
| 937 | void session_notify_clear(struct ltt_session *session) |
| 938 | { |
| 939 | size_t i; |
| 940 | const size_t count = lttng_dynamic_array_get_count( |
| 941 | &session->clear_notifiers); |
| 942 | |
| 943 | for (i = 0; i < count; i++) { |
| 944 | const struct ltt_session_clear_notifier_element *element = |
| 945 | lttng_dynamic_array_get_element( |
| 946 | &session->clear_notifiers, i); |
| 947 | |
| 948 | element->notifier(session, element->user_data); |
| 949 | } |
| 950 | lttng_dynamic_array_clear(&session->clear_notifiers); |
| 951 | } |
| 952 | |
| 953 | static |
| 954 | void session_release(struct urcu_ref *ref) |
| 955 | { |
| 956 | int ret; |
| 957 | struct ltt_ust_session *usess; |
| 958 | struct ltt_kernel_session *ksess; |
| 959 | struct ltt_session *session = container_of(ref, typeof(*session), ref); |
| 960 | const bool session_published = session->published; |
| 961 | |
| 962 | assert(!session->chunk_being_archived); |
| 963 | |
| 964 | usess = session->ust_session; |
| 965 | ksess = session->kernel_session; |
| 966 | |
| 967 | /* Clean kernel session teardown, keeping data for destroy notifier. */ |
| 968 | kernel_destroy_session(ksess); |
| 969 | |
| 970 | /* UST session teardown, keeping data for destroy notifier. */ |
| 971 | if (usess) { |
| 972 | /* Close any relayd session */ |
| 973 | consumer_output_send_destroy_relayd(usess->consumer); |
| 974 | |
| 975 | /* Destroy every UST application related to this session. */ |
| 976 | ret = ust_app_destroy_trace_all(usess); |
| 977 | if (ret) { |
| 978 | ERR("Error in ust_app_destroy_trace_all"); |
| 979 | } |
| 980 | |
| 981 | /* Clean up the rest, keeping destroy notifier data. */ |
| 982 | trace_ust_destroy_session(usess); |
| 983 | } |
| 984 | |
| 985 | /* |
| 986 | * Must notify the kernel thread here to update it's poll set in order to |
| 987 | * remove the channel(s)' fd just destroyed. |
| 988 | */ |
| 989 | ret = notify_thread_pipe(the_kernel_poll_pipe[1]); |
| 990 | if (ret < 0) { |
| 991 | PERROR("write kernel poll pipe"); |
| 992 | } |
| 993 | |
| 994 | DBG("Destroying session %s (id %" PRIu64 ")", session->name, session->id); |
| 995 | |
| 996 | snapshot_destroy(&session->snapshot); |
| 997 | |
| 998 | pthread_mutex_destroy(&session->lock); |
| 999 | |
| 1000 | if (session_published) { |
| 1001 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1002 | del_session_list(session); |
| 1003 | del_session_ht(session); |
| 1004 | } |
| 1005 | session_notify_destruction(session); |
| 1006 | |
| 1007 | consumer_output_put(session->consumer); |
| 1008 | kernel_free_session(ksess); |
| 1009 | session->kernel_session = NULL; |
| 1010 | if (usess) { |
| 1011 | trace_ust_free_session(usess); |
| 1012 | session->ust_session = NULL; |
| 1013 | } |
| 1014 | lttng_dynamic_array_reset(&session->destroy_notifiers); |
| 1015 | lttng_dynamic_array_reset(&session->clear_notifiers); |
| 1016 | free(session->last_archived_chunk_name); |
| 1017 | free(session->base_path); |
| 1018 | free(session); |
| 1019 | if (session_published) { |
| 1020 | /* |
| 1021 | * Broadcast after free-ing to ensure the memory is |
| 1022 | * reclaimed before the main thread exits. |
| 1023 | */ |
| 1024 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1025 | pthread_cond_broadcast(<t_session_list.removal_cond); |
| 1026 | } |
| 1027 | } |
| 1028 | |
| 1029 | /* |
| 1030 | * Acquire a reference to a session. |
| 1031 | * This function may fail (return false); its return value must be checked. |
| 1032 | */ |
| 1033 | bool session_get(struct ltt_session *session) |
| 1034 | { |
| 1035 | return urcu_ref_get_unless_zero(&session->ref); |
| 1036 | } |
| 1037 | |
| 1038 | /* |
| 1039 | * Release a reference to a session. |
| 1040 | */ |
| 1041 | void session_put(struct ltt_session *session) |
| 1042 | { |
| 1043 | if (!session) { |
| 1044 | return; |
| 1045 | } |
| 1046 | /* |
| 1047 | * The session list lock must be held as any session_put() |
| 1048 | * may cause the removal of the session from the session_list. |
| 1049 | */ |
| 1050 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1051 | assert(session->ref.refcount); |
| 1052 | urcu_ref_put(&session->ref, session_release); |
| 1053 | } |
| 1054 | |
| 1055 | /* |
| 1056 | * Destroy a session. |
| 1057 | * |
| 1058 | * This method does not immediately release/free the session as other |
| 1059 | * components may still hold a reference to the session. However, |
| 1060 | * the session should no longer be presented to the user. |
| 1061 | * |
| 1062 | * Releases the session list's reference to the session |
| 1063 | * and marks it as destroyed. Iterations on the session list should be |
| 1064 | * mindful of the "destroyed" flag. |
| 1065 | */ |
| 1066 | void session_destroy(struct ltt_session *session) |
| 1067 | { |
| 1068 | assert(!session->destroyed); |
| 1069 | session->destroyed = true; |
| 1070 | session_put(session); |
| 1071 | } |
| 1072 | |
| 1073 | int session_add_destroy_notifier(struct ltt_session *session, |
| 1074 | ltt_session_destroy_notifier notifier, void *user_data) |
| 1075 | { |
| 1076 | const struct ltt_session_destroy_notifier_element element = { |
| 1077 | .notifier = notifier, |
| 1078 | .user_data = user_data |
| 1079 | }; |
| 1080 | |
| 1081 | return lttng_dynamic_array_add_element(&session->destroy_notifiers, |
| 1082 | &element); |
| 1083 | } |
| 1084 | |
| 1085 | int session_add_clear_notifier(struct ltt_session *session, |
| 1086 | ltt_session_clear_notifier notifier, void *user_data) |
| 1087 | { |
| 1088 | const struct ltt_session_clear_notifier_element element = { |
| 1089 | .notifier = notifier, |
| 1090 | .user_data = user_data |
| 1091 | }; |
| 1092 | |
| 1093 | return lttng_dynamic_array_add_element(&session->clear_notifiers, |
| 1094 | &element); |
| 1095 | } |
| 1096 | |
| 1097 | /* |
| 1098 | * Return a ltt_session structure ptr that matches name. If no session found, |
| 1099 | * NULL is returned. This must be called with the session list lock held using |
| 1100 | * session_lock_list and session_unlock_list. |
| 1101 | * A reference to the session is implicitly acquired by this function. |
| 1102 | */ |
| 1103 | struct ltt_session *session_find_by_name(const char *name) |
| 1104 | { |
| 1105 | struct ltt_session *iter; |
| 1106 | |
| 1107 | assert(name); |
| 1108 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1109 | |
| 1110 | DBG2("Trying to find session by name %s", name); |
| 1111 | |
| 1112 | cds_list_for_each_entry(iter, <t_session_list.head, list) { |
| 1113 | if (!strncmp(iter->name, name, NAME_MAX) && |
| 1114 | !iter->destroyed) { |
| 1115 | goto found; |
| 1116 | } |
| 1117 | } |
| 1118 | |
| 1119 | return NULL; |
| 1120 | found: |
| 1121 | return session_get(iter) ? iter : NULL; |
| 1122 | } |
| 1123 | |
| 1124 | /* |
| 1125 | * Return an ltt_session that matches the id. If no session is found, |
| 1126 | * NULL is returned. This must be called with rcu_read_lock and |
| 1127 | * session list lock held (to guarantee the lifetime of the session). |
| 1128 | */ |
| 1129 | struct ltt_session *session_find_by_id(uint64_t id) |
| 1130 | { |
| 1131 | struct lttng_ht_node_u64 *node; |
| 1132 | struct lttng_ht_iter iter; |
| 1133 | struct ltt_session *ls; |
| 1134 | |
| 1135 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1136 | |
| 1137 | if (!ltt_sessions_ht_by_id) { |
| 1138 | goto end; |
| 1139 | } |
| 1140 | |
| 1141 | lttng_ht_lookup(ltt_sessions_ht_by_id, &id, &iter); |
| 1142 | node = lttng_ht_iter_get_node_u64(&iter); |
| 1143 | if (node == NULL) { |
| 1144 | goto end; |
| 1145 | } |
| 1146 | ls = caa_container_of(node, struct ltt_session, node); |
| 1147 | |
| 1148 | DBG3("Session %" PRIu64 " found by id.", id); |
| 1149 | return session_get(ls) ? ls : NULL; |
| 1150 | |
| 1151 | end: |
| 1152 | DBG3("Session %" PRIu64 " NOT found by id", id); |
| 1153 | return NULL; |
| 1154 | } |
| 1155 | |
| 1156 | /* |
| 1157 | * Create a new session and add it to the session list. |
| 1158 | * Session list lock must be held by the caller. |
| 1159 | */ |
| 1160 | enum lttng_error_code session_create(const char *name, uid_t uid, gid_t gid, |
| 1161 | struct ltt_session **out_session) |
| 1162 | { |
| 1163 | int ret; |
| 1164 | enum lttng_error_code ret_code; |
| 1165 | struct ltt_session *new_session = NULL; |
| 1166 | |
| 1167 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1168 | if (name) { |
| 1169 | struct ltt_session *clashing_session; |
| 1170 | |
| 1171 | clashing_session = session_find_by_name(name); |
| 1172 | if (clashing_session) { |
| 1173 | session_put(clashing_session); |
| 1174 | ret_code = LTTNG_ERR_EXIST_SESS; |
| 1175 | goto error; |
| 1176 | } |
| 1177 | } |
| 1178 | new_session = zmalloc(sizeof(struct ltt_session)); |
| 1179 | if (!new_session) { |
| 1180 | PERROR("Failed to allocate an ltt_session structure"); |
| 1181 | ret_code = LTTNG_ERR_NOMEM; |
| 1182 | goto error; |
| 1183 | } |
| 1184 | |
| 1185 | lttng_dynamic_array_init(&new_session->destroy_notifiers, |
| 1186 | sizeof(struct ltt_session_destroy_notifier_element), |
| 1187 | NULL); |
| 1188 | lttng_dynamic_array_init(&new_session->clear_notifiers, |
| 1189 | sizeof(struct ltt_session_clear_notifier_element), |
| 1190 | NULL); |
| 1191 | urcu_ref_init(&new_session->ref); |
| 1192 | pthread_mutex_init(&new_session->lock, NULL); |
| 1193 | |
| 1194 | new_session->creation_time = time(NULL); |
| 1195 | if (new_session->creation_time == (time_t) -1) { |
| 1196 | PERROR("Failed to sample session creation time"); |
| 1197 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1198 | goto error; |
| 1199 | } |
| 1200 | |
| 1201 | /* Create default consumer output. */ |
| 1202 | new_session->consumer = consumer_create_output(CONSUMER_DST_LOCAL); |
| 1203 | if (new_session->consumer == NULL) { |
| 1204 | ret_code = LTTNG_ERR_NOMEM; |
| 1205 | goto error; |
| 1206 | } |
| 1207 | |
| 1208 | if (name) { |
| 1209 | ret = lttng_strncpy(new_session->name, name, sizeof(new_session->name)); |
| 1210 | if (ret) { |
| 1211 | ret_code = LTTNG_ERR_SESSION_INVALID_CHAR; |
| 1212 | goto error; |
| 1213 | } |
| 1214 | ret = validate_name(name); |
| 1215 | if (ret < 0) { |
| 1216 | ret_code = LTTNG_ERR_SESSION_INVALID_CHAR; |
| 1217 | goto error; |
| 1218 | } |
| 1219 | } else { |
| 1220 | int i = 0; |
| 1221 | bool found_name = false; |
| 1222 | char datetime[16]; |
| 1223 | struct tm *timeinfo; |
| 1224 | |
| 1225 | timeinfo = localtime(&new_session->creation_time); |
| 1226 | if (!timeinfo) { |
| 1227 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1228 | goto error; |
| 1229 | } |
| 1230 | strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo); |
| 1231 | for (i = 0; i < INT_MAX; i++) { |
| 1232 | struct ltt_session *clashing_session; |
| 1233 | |
| 1234 | if (i == 0) { |
| 1235 | ret = snprintf(new_session->name, |
| 1236 | sizeof(new_session->name), |
| 1237 | "%s-%s", |
| 1238 | DEFAULT_SESSION_NAME, |
| 1239 | datetime); |
| 1240 | } else { |
| 1241 | ret = snprintf(new_session->name, |
| 1242 | sizeof(new_session->name), |
| 1243 | "%s%d-%s", |
| 1244 | DEFAULT_SESSION_NAME, i, |
| 1245 | datetime); |
| 1246 | } |
| 1247 | new_session->name_contains_creation_time = true; |
| 1248 | if (ret == -1 || ret >= sizeof(new_session->name)) { |
| 1249 | /* |
| 1250 | * Null-terminate in case the name is used |
| 1251 | * in logging statements. |
| 1252 | */ |
| 1253 | new_session->name[sizeof(new_session->name) - 1] = '\0'; |
| 1254 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1255 | goto error; |
| 1256 | } |
| 1257 | |
| 1258 | clashing_session = |
| 1259 | session_find_by_name(new_session->name); |
| 1260 | session_put(clashing_session); |
| 1261 | if (!clashing_session) { |
| 1262 | found_name = true; |
| 1263 | break; |
| 1264 | } |
| 1265 | } |
| 1266 | if (found_name) { |
| 1267 | DBG("Generated session name \"%s\"", new_session->name); |
| 1268 | new_session->has_auto_generated_name = true; |
| 1269 | } else { |
| 1270 | ERR("Failed to auto-generate a session name"); |
| 1271 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1272 | goto error; |
| 1273 | } |
| 1274 | } |
| 1275 | |
| 1276 | ret = gethostname(new_session->hostname, sizeof(new_session->hostname)); |
| 1277 | if (ret < 0) { |
| 1278 | if (errno == ENAMETOOLONG) { |
| 1279 | new_session->hostname[sizeof(new_session->hostname) - 1] = '\0'; |
| 1280 | ERR("Hostname exceeds the maximal permitted length and has been truncated to %s", |
| 1281 | new_session->hostname); |
| 1282 | } else { |
| 1283 | ret_code = LTTNG_ERR_SESSION_FAIL; |
| 1284 | goto error; |
| 1285 | } |
| 1286 | } |
| 1287 | |
| 1288 | new_session->uid = uid; |
| 1289 | new_session->gid = gid; |
| 1290 | |
| 1291 | ret = snapshot_init(&new_session->snapshot); |
| 1292 | if (ret < 0) { |
| 1293 | ret_code = LTTNG_ERR_NOMEM; |
| 1294 | goto error; |
| 1295 | } |
| 1296 | |
| 1297 | new_session->rotation_state = LTTNG_ROTATION_STATE_NO_ROTATION; |
| 1298 | |
| 1299 | /* Add new session to the session list. */ |
| 1300 | new_session->id = add_session_list(new_session); |
| 1301 | |
| 1302 | /* |
| 1303 | * Add the new session to the ltt_sessions_ht_by_id. |
| 1304 | * No ownership is taken by the hash table; it is merely |
| 1305 | * a wrapper around the session list used for faster access |
| 1306 | * by session id. |
| 1307 | */ |
| 1308 | add_session_ht(new_session); |
| 1309 | new_session->published = true; |
| 1310 | |
| 1311 | /* |
| 1312 | * Consumer is left to NULL since the create_session_uri command will |
| 1313 | * set it up and, if valid, assign it to the session. |
| 1314 | */ |
| 1315 | DBG("Tracing session %s created with ID %" PRIu64 " by uid = %d, gid = %d", |
| 1316 | new_session->name, new_session->id, new_session->uid, |
| 1317 | new_session->gid); |
| 1318 | ret_code = LTTNG_OK; |
| 1319 | end: |
| 1320 | if (new_session) { |
| 1321 | (void) session_get(new_session); |
| 1322 | *out_session = new_session; |
| 1323 | } |
| 1324 | return ret_code; |
| 1325 | error: |
| 1326 | session_put(new_session); |
| 1327 | new_session = NULL; |
| 1328 | goto end; |
| 1329 | } |
| 1330 | |
| 1331 | /* |
| 1332 | * Check if the UID matches the session. Root user has access to all |
| 1333 | * sessions. |
| 1334 | */ |
| 1335 | bool session_access_ok(struct ltt_session *session, uid_t uid) |
| 1336 | { |
| 1337 | assert(session); |
| 1338 | return (uid == session->uid) || uid == 0; |
| 1339 | } |
| 1340 | |
| 1341 | /* |
| 1342 | * Set a session's rotation state and reset all associated state. |
| 1343 | * |
| 1344 | * This function resets the rotation state (check timers, pending |
| 1345 | * flags, etc.) and sets the result of the last rotation. The result |
| 1346 | * can be queries by a liblttng-ctl client. |
| 1347 | * |
| 1348 | * Be careful of the result passed to this function. For instance, |
| 1349 | * on failure to launch a rotation, a client will expect the rotation |
| 1350 | * state to be set to "NO_ROTATION". If an error occurred while the |
| 1351 | * rotation was "ONGOING", result should be set to "ERROR", which will |
| 1352 | * allow a client to report it. |
| 1353 | * |
| 1354 | * Must be called with the session and session_list locks held. |
| 1355 | */ |
| 1356 | int session_reset_rotation_state(struct ltt_session *session, |
| 1357 | enum lttng_rotation_state result) |
| 1358 | { |
| 1359 | int ret = 0; |
| 1360 | |
| 1361 | ASSERT_LOCKED(ltt_session_list.lock); |
| 1362 | ASSERT_LOCKED(session->lock); |
| 1363 | |
| 1364 | session->rotation_state = result; |
| 1365 | if (session->rotation_pending_check_timer_enabled) { |
| 1366 | ret = timer_session_rotation_pending_check_stop(session); |
| 1367 | } |
| 1368 | if (session->chunk_being_archived) { |
| 1369 | uint64_t chunk_id; |
| 1370 | enum lttng_trace_chunk_status chunk_status; |
| 1371 | |
| 1372 | chunk_status = lttng_trace_chunk_get_id( |
| 1373 | session->chunk_being_archived, |
| 1374 | &chunk_id); |
| 1375 | assert(chunk_status == LTTNG_TRACE_CHUNK_STATUS_OK); |
| 1376 | LTTNG_OPTIONAL_SET(&session->last_archived_chunk_id, |
| 1377 | chunk_id); |
| 1378 | lttng_trace_chunk_put(session->chunk_being_archived); |
| 1379 | session->chunk_being_archived = NULL; |
| 1380 | /* |
| 1381 | * Fire the clear reply notifiers if we are completing a clear |
| 1382 | * rotation. |
| 1383 | */ |
| 1384 | session_notify_clear(session); |
| 1385 | } |
| 1386 | return ret; |
| 1387 | } |
| 1388 | |
| 1389 | /* |
| 1390 | * Sample the id of a session looked up via its name. |
| 1391 | * Here the term "sampling" hint the caller that this return the id at a given |
| 1392 | * point in time with no guarantee that the session for which the id was |
| 1393 | * sampled still exist at that point. |
| 1394 | * |
| 1395 | * Return 0 when the session is not found, |
| 1396 | * Return 1 when the session is found and set `id`. |
| 1397 | */ |
| 1398 | bool sample_session_id_by_name(const char *name, uint64_t *id) |
| 1399 | { |
| 1400 | bool found = false; |
| 1401 | struct lttng_ht_node_str *node; |
| 1402 | struct lttng_ht_iter iter; |
| 1403 | struct ltt_session *ls; |
| 1404 | |
| 1405 | rcu_read_lock(); |
| 1406 | |
| 1407 | if (!ltt_sessions_ht_by_name) { |
| 1408 | found = false; |
| 1409 | goto end; |
| 1410 | } |
| 1411 | |
| 1412 | lttng_ht_lookup(ltt_sessions_ht_by_name, name, &iter); |
| 1413 | node = lttng_ht_iter_get_node_str(&iter); |
| 1414 | if (node == NULL) { |
| 1415 | found = false; |
| 1416 | goto end; |
| 1417 | } |
| 1418 | |
| 1419 | ls = caa_container_of(node, struct ltt_session, node_by_name); |
| 1420 | *id = ls->id; |
| 1421 | found = true; |
| 1422 | |
| 1423 | DBG3("Session id `%" PRIu64 "` sampled for session `%s", *id, name); |
| 1424 | end: |
| 1425 | rcu_read_unlock(); |
| 1426 | return found; |
| 1427 | } |