| 1 | /* |
| 2 | * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU General Public License, version 2 only, as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 9 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 10 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 11 | * more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License along with |
| 14 | * this program; if not, write to the Free Software Foundation, Inc., 51 |
| 15 | * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 16 | */ |
| 17 | |
| 18 | #define _LGPL_SOURCE |
| 19 | #include <assert.h> |
| 20 | #include <inttypes.h> |
| 21 | |
| 22 | #include <common/common.h> |
| 23 | #include <common/hashtable/utils.h> |
| 24 | #include <lttng/lttng.h> |
| 25 | |
| 26 | #include "ust-registry.h" |
| 27 | #include "ust-app.h" |
| 28 | #include "ust-field-utils.h" |
| 29 | #include "utils.h" |
| 30 | #include "lttng-sessiond.h" |
| 31 | #include "notification-thread-commands.h" |
| 32 | |
| 33 | |
| 34 | /* |
| 35 | * Hash table match function for event in the registry. |
| 36 | */ |
| 37 | static int ht_match_event(struct cds_lfht_node *node, const void *_key) |
| 38 | { |
| 39 | const struct ust_registry_event *key; |
| 40 | struct ust_registry_event *event; |
| 41 | int i; |
| 42 | |
| 43 | assert(node); |
| 44 | assert(_key); |
| 45 | |
| 46 | event = caa_container_of(node, struct ust_registry_event, node.node); |
| 47 | assert(event); |
| 48 | key = _key; |
| 49 | |
| 50 | /* It has to be a perfect match. First, compare the event names. */ |
| 51 | if (strncmp(event->name, key->name, sizeof(event->name))) { |
| 52 | goto no_match; |
| 53 | } |
| 54 | |
| 55 | /* Compare log levels. */ |
| 56 | if (event->loglevel_value != key->loglevel_value) { |
| 57 | goto no_match; |
| 58 | } |
| 59 | |
| 60 | /* Compare the number of fields. */ |
| 61 | if (event->nr_fields != key->nr_fields) { |
| 62 | goto no_match; |
| 63 | } |
| 64 | |
| 65 | /* Compare each field individually. */ |
| 66 | for (i = 0; i < event->nr_fields; i++) { |
| 67 | if (!match_ustctl_field(&event->fields[i], &key->fields[i])) { |
| 68 | goto no_match; |
| 69 | } |
| 70 | } |
| 71 | |
| 72 | /* Compare model URI. */ |
| 73 | if (event->model_emf_uri != NULL && key->model_emf_uri == NULL) { |
| 74 | goto no_match; |
| 75 | } else if(event->model_emf_uri == NULL && key->model_emf_uri != NULL) { |
| 76 | goto no_match; |
| 77 | } else if (event->model_emf_uri != NULL && key->model_emf_uri != NULL) { |
| 78 | if (strcmp(event->model_emf_uri, key->model_emf_uri)) { |
| 79 | goto no_match; |
| 80 | } |
| 81 | } |
| 82 | |
| 83 | /* Match */ |
| 84 | return 1; |
| 85 | |
| 86 | no_match: |
| 87 | return 0; |
| 88 | } |
| 89 | |
| 90 | static unsigned long ht_hash_event(void *_key, unsigned long seed) |
| 91 | { |
| 92 | uint64_t hashed_key; |
| 93 | const struct ust_registry_event *key = _key; |
| 94 | |
| 95 | assert(key); |
| 96 | |
| 97 | hashed_key = (uint64_t) hash_key_str(key->name, seed); |
| 98 | |
| 99 | return hash_key_u64(&hashed_key, seed); |
| 100 | } |
| 101 | |
| 102 | static int compare_enums(const struct ust_registry_enum *reg_enum_a, |
| 103 | const struct ust_registry_enum *reg_enum_b) |
| 104 | { |
| 105 | int ret = 0; |
| 106 | size_t i; |
| 107 | |
| 108 | assert(strcmp(reg_enum_a->name, reg_enum_b->name) == 0); |
| 109 | if (reg_enum_a->nr_entries != reg_enum_b->nr_entries) { |
| 110 | ret = -1; |
| 111 | goto end; |
| 112 | } |
| 113 | for (i = 0; i < reg_enum_a->nr_entries; i++) { |
| 114 | const struct ustctl_enum_entry *entries_a, *entries_b; |
| 115 | |
| 116 | entries_a = ®_enum_a->entries[i]; |
| 117 | entries_b = ®_enum_b->entries[i]; |
| 118 | if (entries_a->start.value != entries_b->start.value) { |
| 119 | ret = -1; |
| 120 | goto end; |
| 121 | } |
| 122 | if (entries_a->end.value != entries_b->end.value) { |
| 123 | ret = -1; |
| 124 | goto end; |
| 125 | } |
| 126 | if (entries_a->start.signedness != entries_b->start.signedness) { |
| 127 | ret = -1; |
| 128 | goto end; |
| 129 | } |
| 130 | if (entries_a->end.signedness != entries_b->end.signedness) { |
| 131 | ret = -1; |
| 132 | goto end; |
| 133 | } |
| 134 | |
| 135 | if (strcmp(entries_a->string, entries_b->string)) { |
| 136 | ret = -1; |
| 137 | goto end; |
| 138 | } |
| 139 | } |
| 140 | end: |
| 141 | return ret; |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * Hash table match function for enumerations in the session. Match is |
| 146 | * performed on enumeration name, and confirmed by comparing the enum |
| 147 | * entries. |
| 148 | */ |
| 149 | static int ht_match_enum(struct cds_lfht_node *node, const void *_key) |
| 150 | { |
| 151 | struct ust_registry_enum *_enum; |
| 152 | const struct ust_registry_enum *key; |
| 153 | |
| 154 | assert(node); |
| 155 | assert(_key); |
| 156 | |
| 157 | _enum = caa_container_of(node, struct ust_registry_enum, |
| 158 | node.node); |
| 159 | assert(_enum); |
| 160 | key = _key; |
| 161 | |
| 162 | if (strncmp(_enum->name, key->name, LTTNG_UST_SYM_NAME_LEN)) { |
| 163 | goto no_match; |
| 164 | } |
| 165 | if (compare_enums(_enum, key)) { |
| 166 | goto no_match; |
| 167 | } |
| 168 | |
| 169 | /* Match. */ |
| 170 | return 1; |
| 171 | |
| 172 | no_match: |
| 173 | return 0; |
| 174 | } |
| 175 | |
| 176 | /* |
| 177 | * Hash table match function for enumerations in the session. Match is |
| 178 | * performed by enumeration ID. |
| 179 | */ |
| 180 | static int ht_match_enum_id(struct cds_lfht_node *node, const void *_key) |
| 181 | { |
| 182 | struct ust_registry_enum *_enum; |
| 183 | const struct ust_registry_enum *key = _key; |
| 184 | |
| 185 | assert(node); |
| 186 | assert(_key); |
| 187 | |
| 188 | _enum = caa_container_of(node, struct ust_registry_enum, node.node); |
| 189 | assert(_enum); |
| 190 | |
| 191 | if (_enum->id != key->id) { |
| 192 | goto no_match; |
| 193 | } |
| 194 | |
| 195 | /* Match. */ |
| 196 | return 1; |
| 197 | |
| 198 | no_match: |
| 199 | return 0; |
| 200 | } |
| 201 | |
| 202 | /* |
| 203 | * Hash table hash function for enumerations in the session. The |
| 204 | * enumeration name is used for hashing. |
| 205 | */ |
| 206 | static unsigned long ht_hash_enum(void *_key, unsigned long seed) |
| 207 | { |
| 208 | struct ust_registry_enum *key = _key; |
| 209 | |
| 210 | assert(key); |
| 211 | return hash_key_str(key->name, seed); |
| 212 | } |
| 213 | |
| 214 | /* |
| 215 | * Return negative value on error, 0 if OK. |
| 216 | * |
| 217 | * TODO: we could add stricter verification of more types to catch |
| 218 | * errors in liblttng-ust implementation earlier than consumption by the |
| 219 | * trace reader. |
| 220 | */ |
| 221 | static |
| 222 | int validate_event_field(struct ustctl_field *field, |
| 223 | const char *event_name, |
| 224 | struct ust_app *app) |
| 225 | { |
| 226 | int ret = 0; |
| 227 | |
| 228 | switch(field->type.atype) { |
| 229 | case ustctl_atype_integer: |
| 230 | case ustctl_atype_enum: |
| 231 | case ustctl_atype_array: |
| 232 | case ustctl_atype_sequence: |
| 233 | case ustctl_atype_string: |
| 234 | case ustctl_atype_variant: |
| 235 | break; |
| 236 | case ustctl_atype_struct: |
| 237 | if (field->type.u._struct.nr_fields != 0) { |
| 238 | WARN("Unsupported non-empty struct field."); |
| 239 | ret = -EINVAL; |
| 240 | goto end; |
| 241 | } |
| 242 | break; |
| 243 | |
| 244 | case ustctl_atype_float: |
| 245 | switch (field->type.u.basic._float.mant_dig) { |
| 246 | case 0: |
| 247 | WARN("UST application '%s' (pid: %d) has unknown float mantissa '%u' " |
| 248 | "in field '%s', rejecting event '%s'", |
| 249 | app->name, app->pid, |
| 250 | field->type.u.basic._float.mant_dig, |
| 251 | field->name, |
| 252 | event_name); |
| 253 | ret = -EINVAL; |
| 254 | goto end; |
| 255 | default: |
| 256 | break; |
| 257 | } |
| 258 | break; |
| 259 | |
| 260 | default: |
| 261 | ret = -ENOENT; |
| 262 | goto end; |
| 263 | } |
| 264 | end: |
| 265 | return ret; |
| 266 | } |
| 267 | |
| 268 | static |
| 269 | int validate_event_fields(size_t nr_fields, struct ustctl_field *fields, |
| 270 | const char *event_name, struct ust_app *app) |
| 271 | { |
| 272 | unsigned int i; |
| 273 | |
| 274 | for (i = 0; i < nr_fields; i++) { |
| 275 | if (validate_event_field(&fields[i], event_name, app) < 0) |
| 276 | return -EINVAL; |
| 277 | } |
| 278 | return 0; |
| 279 | } |
| 280 | |
| 281 | /* |
| 282 | * Allocate event and initialize it. This does NOT set a valid event id from a |
| 283 | * registry. |
| 284 | */ |
| 285 | static struct ust_registry_event *alloc_event(int session_objd, |
| 286 | int channel_objd, char *name, char *sig, size_t nr_fields, |
| 287 | struct ustctl_field *fields, int loglevel_value, |
| 288 | char *model_emf_uri, struct ust_app *app) |
| 289 | { |
| 290 | struct ust_registry_event *event = NULL; |
| 291 | |
| 292 | /* |
| 293 | * Ensure that the field content is valid. |
| 294 | */ |
| 295 | if (validate_event_fields(nr_fields, fields, name, app) < 0) { |
| 296 | return NULL; |
| 297 | } |
| 298 | |
| 299 | event = zmalloc(sizeof(*event)); |
| 300 | if (!event) { |
| 301 | PERROR("zmalloc ust registry event"); |
| 302 | goto error; |
| 303 | } |
| 304 | |
| 305 | event->session_objd = session_objd; |
| 306 | event->channel_objd = channel_objd; |
| 307 | /* Allocated by ustctl. */ |
| 308 | event->signature = sig; |
| 309 | event->nr_fields = nr_fields; |
| 310 | event->fields = fields; |
| 311 | event->loglevel_value = loglevel_value; |
| 312 | event->model_emf_uri = model_emf_uri; |
| 313 | if (name) { |
| 314 | /* Copy event name and force NULL byte. */ |
| 315 | strncpy(event->name, name, sizeof(event->name)); |
| 316 | event->name[sizeof(event->name) - 1] = '\0'; |
| 317 | } |
| 318 | cds_lfht_node_init(&event->node.node); |
| 319 | |
| 320 | error: |
| 321 | return event; |
| 322 | } |
| 323 | |
| 324 | /* |
| 325 | * Free event data structure. This does NOT delete it from any hash table. It's |
| 326 | * safe to pass a NULL pointer. This shoudl be called inside a call RCU if the |
| 327 | * event is previously deleted from a rcu hash table. |
| 328 | */ |
| 329 | static void destroy_event(struct ust_registry_event *event) |
| 330 | { |
| 331 | if (!event) { |
| 332 | return; |
| 333 | } |
| 334 | |
| 335 | free(event->fields); |
| 336 | free(event->model_emf_uri); |
| 337 | free(event->signature); |
| 338 | free(event); |
| 339 | } |
| 340 | |
| 341 | /* |
| 342 | * Destroy event function call of the call RCU. |
| 343 | */ |
| 344 | static void destroy_event_rcu(struct rcu_head *head) |
| 345 | { |
| 346 | struct lttng_ht_node_u64 *node = |
| 347 | caa_container_of(head, struct lttng_ht_node_u64, head); |
| 348 | struct ust_registry_event *event = |
| 349 | caa_container_of(node, struct ust_registry_event, node); |
| 350 | |
| 351 | destroy_event(event); |
| 352 | } |
| 353 | |
| 354 | /* |
| 355 | * Find an event using the name and signature in the given registry. RCU read |
| 356 | * side lock MUST be acquired before calling this function and as long as the |
| 357 | * event reference is kept by the caller. |
| 358 | * |
| 359 | * On success, the event pointer is returned else NULL. |
| 360 | */ |
| 361 | struct ust_registry_event *ust_registry_find_event( |
| 362 | struct ust_registry_channel *chan, char *name, char *sig) |
| 363 | { |
| 364 | struct lttng_ht_node_u64 *node; |
| 365 | struct lttng_ht_iter iter; |
| 366 | struct ust_registry_event *event = NULL; |
| 367 | struct ust_registry_event key; |
| 368 | |
| 369 | assert(chan); |
| 370 | assert(name); |
| 371 | assert(sig); |
| 372 | |
| 373 | /* Setup key for the match function. */ |
| 374 | strncpy(key.name, name, sizeof(key.name)); |
| 375 | key.name[sizeof(key.name) - 1] = '\0'; |
| 376 | key.signature = sig; |
| 377 | |
| 378 | cds_lfht_lookup(chan->ht->ht, chan->ht->hash_fct(&key, lttng_ht_seed), |
| 379 | chan->ht->match_fct, &key, &iter.iter); |
| 380 | node = lttng_ht_iter_get_node_u64(&iter); |
| 381 | if (!node) { |
| 382 | goto end; |
| 383 | } |
| 384 | event = caa_container_of(node, struct ust_registry_event, node); |
| 385 | |
| 386 | end: |
| 387 | return event; |
| 388 | } |
| 389 | |
| 390 | /* |
| 391 | * Create a ust_registry_event from the given parameters and add it to the |
| 392 | * registry hash table. If event_id is valid, it is set with the newly created |
| 393 | * event id. |
| 394 | * |
| 395 | * On success, return 0 else a negative value. The created event MUST be unique |
| 396 | * so on duplicate entry -EINVAL is returned. On error, event_id is untouched. |
| 397 | * |
| 398 | * Should be called with session registry mutex held. |
| 399 | */ |
| 400 | int ust_registry_create_event(struct ust_registry_session *session, |
| 401 | uint64_t chan_key, int session_objd, int channel_objd, char *name, |
| 402 | char *sig, size_t nr_fields, struct ustctl_field *fields, |
| 403 | int loglevel_value, char *model_emf_uri, int buffer_type, |
| 404 | uint32_t *event_id_p, struct ust_app *app) |
| 405 | { |
| 406 | int ret; |
| 407 | uint32_t event_id; |
| 408 | struct cds_lfht_node *nptr; |
| 409 | struct ust_registry_event *event = NULL; |
| 410 | struct ust_registry_channel *chan; |
| 411 | |
| 412 | assert(session); |
| 413 | assert(name); |
| 414 | assert(sig); |
| 415 | assert(event_id_p); |
| 416 | |
| 417 | rcu_read_lock(); |
| 418 | |
| 419 | /* |
| 420 | * This should not happen but since it comes from the UST tracer, an |
| 421 | * external party, don't assert and simply validate values. |
| 422 | */ |
| 423 | if (session_objd < 0 || channel_objd < 0) { |
| 424 | ret = -EINVAL; |
| 425 | goto error_free; |
| 426 | } |
| 427 | |
| 428 | chan = ust_registry_channel_find(session, chan_key); |
| 429 | if (!chan) { |
| 430 | ret = -EINVAL; |
| 431 | goto error_free; |
| 432 | } |
| 433 | |
| 434 | /* Check if we've reached the maximum possible id. */ |
| 435 | if (ust_registry_is_max_id(chan->used_event_id)) { |
| 436 | ret = -ENOENT; |
| 437 | goto error_free; |
| 438 | } |
| 439 | |
| 440 | event = alloc_event(session_objd, channel_objd, name, sig, nr_fields, |
| 441 | fields, loglevel_value, model_emf_uri, app); |
| 442 | if (!event) { |
| 443 | ret = -ENOMEM; |
| 444 | goto error_free; |
| 445 | } |
| 446 | |
| 447 | DBG3("UST registry creating event with event: %s, sig: %s, id: %u, " |
| 448 | "chan_objd: %u, sess_objd: %u, chan_id: %u", event->name, |
| 449 | event->signature, event->id, event->channel_objd, |
| 450 | event->session_objd, chan->chan_id); |
| 451 | |
| 452 | /* |
| 453 | * This is an add unique with a custom match function for event. The node |
| 454 | * are matched using the event name and signature. |
| 455 | */ |
| 456 | nptr = cds_lfht_add_unique(chan->ht->ht, chan->ht->hash_fct(event, |
| 457 | lttng_ht_seed), chan->ht->match_fct, event, &event->node.node); |
| 458 | if (nptr != &event->node.node) { |
| 459 | if (buffer_type == LTTNG_BUFFER_PER_UID) { |
| 460 | /* |
| 461 | * This is normal, we just have to send the event id of the |
| 462 | * returned node and make sure we destroy the previously allocated |
| 463 | * event object. |
| 464 | */ |
| 465 | destroy_event(event); |
| 466 | event = caa_container_of(nptr, struct ust_registry_event, |
| 467 | node.node); |
| 468 | assert(event); |
| 469 | event_id = event->id; |
| 470 | } else { |
| 471 | ERR("UST registry create event add unique failed for event: %s, " |
| 472 | "sig: %s, id: %u, chan_objd: %u, sess_objd: %u", |
| 473 | event->name, event->signature, event->id, |
| 474 | event->channel_objd, event->session_objd); |
| 475 | ret = -EINVAL; |
| 476 | goto error_unlock; |
| 477 | } |
| 478 | } else { |
| 479 | /* Request next event id if the node was successfully added. */ |
| 480 | event_id = event->id = ust_registry_get_next_event_id(chan); |
| 481 | } |
| 482 | |
| 483 | *event_id_p = event_id; |
| 484 | |
| 485 | if (!event->metadata_dumped) { |
| 486 | /* Append to metadata */ |
| 487 | ret = ust_metadata_event_statedump(session, chan, event); |
| 488 | if (ret) { |
| 489 | ERR("Error appending event metadata (errno = %d)", ret); |
| 490 | rcu_read_unlock(); |
| 491 | return ret; |
| 492 | } |
| 493 | } |
| 494 | |
| 495 | rcu_read_unlock(); |
| 496 | return 0; |
| 497 | |
| 498 | error_free: |
| 499 | free(sig); |
| 500 | free(fields); |
| 501 | free(model_emf_uri); |
| 502 | error_unlock: |
| 503 | rcu_read_unlock(); |
| 504 | destroy_event(event); |
| 505 | return ret; |
| 506 | } |
| 507 | |
| 508 | /* |
| 509 | * For a given event in a registry, delete the entry and destroy the event. |
| 510 | * This MUST be called within a RCU read side lock section. |
| 511 | */ |
| 512 | void ust_registry_destroy_event(struct ust_registry_channel *chan, |
| 513 | struct ust_registry_event *event) |
| 514 | { |
| 515 | int ret; |
| 516 | struct lttng_ht_iter iter; |
| 517 | |
| 518 | assert(chan); |
| 519 | assert(event); |
| 520 | |
| 521 | /* Delete the node first. */ |
| 522 | iter.iter.node = &event->node.node; |
| 523 | ret = lttng_ht_del(chan->ht, &iter); |
| 524 | assert(!ret); |
| 525 | |
| 526 | call_rcu(&event->node.head, destroy_event_rcu); |
| 527 | |
| 528 | return; |
| 529 | } |
| 530 | |
| 531 | static void destroy_enum(struct ust_registry_enum *reg_enum) |
| 532 | { |
| 533 | if (!reg_enum) { |
| 534 | return; |
| 535 | } |
| 536 | free(reg_enum->entries); |
| 537 | free(reg_enum); |
| 538 | } |
| 539 | |
| 540 | static void destroy_enum_rcu(struct rcu_head *head) |
| 541 | { |
| 542 | struct ust_registry_enum *reg_enum = |
| 543 | caa_container_of(head, struct ust_registry_enum, rcu_head); |
| 544 | |
| 545 | destroy_enum(reg_enum); |
| 546 | } |
| 547 | |
| 548 | /* |
| 549 | * Lookup enumeration by name and comparing enumeration entries. |
| 550 | * Needs to be called from RCU read-side critical section. |
| 551 | */ |
| 552 | struct ust_registry_enum * |
| 553 | ust_registry_lookup_enum(struct ust_registry_session *session, |
| 554 | const struct ust_registry_enum *reg_enum_lookup) |
| 555 | { |
| 556 | struct ust_registry_enum *reg_enum = NULL; |
| 557 | struct lttng_ht_node_str *node; |
| 558 | struct lttng_ht_iter iter; |
| 559 | |
| 560 | cds_lfht_lookup(session->enums->ht, |
| 561 | ht_hash_enum((void *) reg_enum_lookup, lttng_ht_seed), |
| 562 | ht_match_enum, reg_enum_lookup, &iter.iter); |
| 563 | node = lttng_ht_iter_get_node_str(&iter); |
| 564 | if (!node) { |
| 565 | goto end; |
| 566 | } |
| 567 | reg_enum = caa_container_of(node, struct ust_registry_enum, node); |
| 568 | end: |
| 569 | return reg_enum; |
| 570 | } |
| 571 | |
| 572 | /* |
| 573 | * Lookup enumeration by enum ID. |
| 574 | * Needs to be called from RCU read-side critical section. |
| 575 | */ |
| 576 | struct ust_registry_enum * |
| 577 | ust_registry_lookup_enum_by_id(struct ust_registry_session *session, |
| 578 | const char *enum_name, uint64_t enum_id) |
| 579 | { |
| 580 | struct ust_registry_enum *reg_enum = NULL; |
| 581 | struct lttng_ht_node_str *node; |
| 582 | struct lttng_ht_iter iter; |
| 583 | struct ust_registry_enum reg_enum_lookup; |
| 584 | |
| 585 | memset(®_enum_lookup, 0, sizeof(reg_enum_lookup)); |
| 586 | strncpy(reg_enum_lookup.name, enum_name, LTTNG_UST_SYM_NAME_LEN); |
| 587 | reg_enum_lookup.name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0'; |
| 588 | reg_enum_lookup.id = enum_id; |
| 589 | cds_lfht_lookup(session->enums->ht, |
| 590 | ht_hash_enum((void *) ®_enum_lookup, lttng_ht_seed), |
| 591 | ht_match_enum_id, ®_enum_lookup, &iter.iter); |
| 592 | node = lttng_ht_iter_get_node_str(&iter); |
| 593 | if (!node) { |
| 594 | goto end; |
| 595 | } |
| 596 | reg_enum = caa_container_of(node, struct ust_registry_enum, node); |
| 597 | end: |
| 598 | return reg_enum; |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * Create a ust_registry_enum from the given parameters and add it to the |
| 603 | * registry hash table, or find it if already there. |
| 604 | * |
| 605 | * On success, return 0 else a negative value. |
| 606 | * |
| 607 | * Should be called with session registry mutex held. |
| 608 | * |
| 609 | * We receive ownership of entries. |
| 610 | */ |
| 611 | int ust_registry_create_or_find_enum(struct ust_registry_session *session, |
| 612 | int session_objd, char *enum_name, |
| 613 | struct ustctl_enum_entry *entries, size_t nr_entries, |
| 614 | uint64_t *enum_id) |
| 615 | { |
| 616 | int ret = 0; |
| 617 | struct cds_lfht_node *nodep; |
| 618 | struct ust_registry_enum *reg_enum = NULL, *old_reg_enum; |
| 619 | |
| 620 | assert(session); |
| 621 | assert(enum_name); |
| 622 | |
| 623 | rcu_read_lock(); |
| 624 | |
| 625 | /* |
| 626 | * This should not happen but since it comes from the UST tracer, an |
| 627 | * external party, don't assert and simply validate values. |
| 628 | */ |
| 629 | if (session_objd < 0) { |
| 630 | ret = -EINVAL; |
| 631 | goto end; |
| 632 | } |
| 633 | |
| 634 | /* Check if the enumeration was already dumped */ |
| 635 | reg_enum = zmalloc(sizeof(*reg_enum)); |
| 636 | if (!reg_enum) { |
| 637 | PERROR("zmalloc ust registry enumeration"); |
| 638 | ret = -ENOMEM; |
| 639 | goto end; |
| 640 | } |
| 641 | strncpy(reg_enum->name, enum_name, LTTNG_UST_SYM_NAME_LEN); |
| 642 | reg_enum->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0'; |
| 643 | /* entries will be owned by reg_enum. */ |
| 644 | reg_enum->entries = entries; |
| 645 | reg_enum->nr_entries = nr_entries; |
| 646 | entries = NULL; |
| 647 | |
| 648 | old_reg_enum = ust_registry_lookup_enum(session, reg_enum); |
| 649 | if (old_reg_enum) { |
| 650 | DBG("enum %s already in sess_objd: %u", enum_name, session_objd); |
| 651 | /* Fall through. Use prior enum. */ |
| 652 | destroy_enum(reg_enum); |
| 653 | reg_enum = old_reg_enum; |
| 654 | } else { |
| 655 | DBG("UST registry creating enum: %s, sess_objd: %u", |
| 656 | enum_name, session_objd); |
| 657 | if (session->next_enum_id == -1ULL) { |
| 658 | ret = -EOVERFLOW; |
| 659 | destroy_enum(reg_enum); |
| 660 | goto end; |
| 661 | } |
| 662 | reg_enum->id = session->next_enum_id++; |
| 663 | cds_lfht_node_init(®_enum->node.node); |
| 664 | nodep = cds_lfht_add_unique(session->enums->ht, |
| 665 | ht_hash_enum(reg_enum, lttng_ht_seed), |
| 666 | ht_match_enum_id, reg_enum, |
| 667 | ®_enum->node.node); |
| 668 | assert(nodep == ®_enum->node.node); |
| 669 | } |
| 670 | DBG("UST registry reply with enum %s with id %" PRIu64 " in sess_objd: %u", |
| 671 | enum_name, reg_enum->id, session_objd); |
| 672 | *enum_id = reg_enum->id; |
| 673 | end: |
| 674 | free(entries); |
| 675 | rcu_read_unlock(); |
| 676 | return ret; |
| 677 | } |
| 678 | |
| 679 | /* |
| 680 | * For a given enumeration in a registry, delete the entry and destroy |
| 681 | * the enumeration. |
| 682 | * This MUST be called within a RCU read side lock section. |
| 683 | */ |
| 684 | void ust_registry_destroy_enum(struct ust_registry_session *reg_session, |
| 685 | struct ust_registry_enum *reg_enum) |
| 686 | { |
| 687 | int ret; |
| 688 | struct lttng_ht_iter iter; |
| 689 | |
| 690 | assert(reg_session); |
| 691 | assert(reg_enum); |
| 692 | |
| 693 | /* Delete the node first. */ |
| 694 | iter.iter.node = ®_enum->node.node; |
| 695 | ret = lttng_ht_del(reg_session->enums, &iter); |
| 696 | assert(!ret); |
| 697 | call_rcu(®_enum->rcu_head, destroy_enum_rcu); |
| 698 | } |
| 699 | |
| 700 | /* |
| 701 | * We need to execute ht_destroy outside of RCU read-side critical |
| 702 | * section and outside of call_rcu thread, so we postpone its execution |
| 703 | * using ht_cleanup_push. It is simpler than to change the semantic of |
| 704 | * the many callers of delete_ust_app_session(). |
| 705 | */ |
| 706 | static |
| 707 | void destroy_channel_rcu(struct rcu_head *head) |
| 708 | { |
| 709 | struct ust_registry_channel *chan = |
| 710 | caa_container_of(head, struct ust_registry_channel, rcu_head); |
| 711 | |
| 712 | if (chan->ht) { |
| 713 | ht_cleanup_push(chan->ht); |
| 714 | } |
| 715 | free(chan->ctx_fields); |
| 716 | free(chan); |
| 717 | } |
| 718 | |
| 719 | /* |
| 720 | * Destroy every element of the registry and free the memory. This does NOT |
| 721 | * free the registry pointer since it might not have been allocated before so |
| 722 | * it's the caller responsability. |
| 723 | */ |
| 724 | static void destroy_channel(struct ust_registry_channel *chan, bool notif) |
| 725 | { |
| 726 | struct lttng_ht_iter iter; |
| 727 | struct ust_registry_event *event; |
| 728 | enum lttng_error_code cmd_ret; |
| 729 | |
| 730 | assert(chan); |
| 731 | |
| 732 | if (notif) { |
| 733 | cmd_ret = notification_thread_command_remove_channel( |
| 734 | notification_thread_handle, chan->consumer_key, |
| 735 | LTTNG_DOMAIN_UST); |
| 736 | if (cmd_ret != LTTNG_OK) { |
| 737 | ERR("Failed to remove channel from notification thread"); |
| 738 | } |
| 739 | } |
| 740 | |
| 741 | rcu_read_lock(); |
| 742 | /* Destroy all event associated with this registry. */ |
| 743 | cds_lfht_for_each_entry(chan->ht->ht, &iter.iter, event, node.node) { |
| 744 | /* Delete the node from the ht and free it. */ |
| 745 | ust_registry_destroy_event(chan, event); |
| 746 | } |
| 747 | rcu_read_unlock(); |
| 748 | call_rcu(&chan->rcu_head, destroy_channel_rcu); |
| 749 | } |
| 750 | |
| 751 | /* |
| 752 | * Initialize registry with default values. |
| 753 | */ |
| 754 | int ust_registry_channel_add(struct ust_registry_session *session, |
| 755 | uint64_t key) |
| 756 | { |
| 757 | int ret = 0; |
| 758 | struct ust_registry_channel *chan; |
| 759 | |
| 760 | assert(session); |
| 761 | |
| 762 | chan = zmalloc(sizeof(*chan)); |
| 763 | if (!chan) { |
| 764 | PERROR("zmalloc ust registry channel"); |
| 765 | ret = -ENOMEM; |
| 766 | goto error_alloc; |
| 767 | } |
| 768 | |
| 769 | chan->ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); |
| 770 | if (!chan->ht) { |
| 771 | ret = -ENOMEM; |
| 772 | goto error; |
| 773 | } |
| 774 | |
| 775 | /* Set custom match function. */ |
| 776 | chan->ht->match_fct = ht_match_event; |
| 777 | chan->ht->hash_fct = ht_hash_event; |
| 778 | |
| 779 | /* |
| 780 | * Assign a channel ID right now since the event notification comes |
| 781 | * *before* the channel notify so the ID needs to be set at this point so |
| 782 | * the metadata can be dumped for that event. |
| 783 | */ |
| 784 | if (ust_registry_is_max_id(session->used_channel_id)) { |
| 785 | ret = -1; |
| 786 | goto error; |
| 787 | } |
| 788 | chan->chan_id = ust_registry_get_next_chan_id(session); |
| 789 | |
| 790 | rcu_read_lock(); |
| 791 | lttng_ht_node_init_u64(&chan->node, key); |
| 792 | lttng_ht_add_unique_u64(session->channels, &chan->node); |
| 793 | rcu_read_unlock(); |
| 794 | |
| 795 | return 0; |
| 796 | |
| 797 | error: |
| 798 | destroy_channel(chan, false); |
| 799 | error_alloc: |
| 800 | return ret; |
| 801 | } |
| 802 | |
| 803 | /* |
| 804 | * Find a channel in the given registry. RCU read side lock MUST be acquired |
| 805 | * before calling this function and as long as the event reference is kept by |
| 806 | * the caller. |
| 807 | * |
| 808 | * On success, the pointer is returned else NULL. |
| 809 | */ |
| 810 | struct ust_registry_channel *ust_registry_channel_find( |
| 811 | struct ust_registry_session *session, uint64_t key) |
| 812 | { |
| 813 | struct lttng_ht_node_u64 *node; |
| 814 | struct lttng_ht_iter iter; |
| 815 | struct ust_registry_channel *chan = NULL; |
| 816 | |
| 817 | assert(session); |
| 818 | assert(session->channels); |
| 819 | |
| 820 | DBG3("UST registry channel finding key %" PRIu64, key); |
| 821 | |
| 822 | lttng_ht_lookup(session->channels, &key, &iter); |
| 823 | node = lttng_ht_iter_get_node_u64(&iter); |
| 824 | if (!node) { |
| 825 | goto end; |
| 826 | } |
| 827 | chan = caa_container_of(node, struct ust_registry_channel, node); |
| 828 | |
| 829 | end: |
| 830 | return chan; |
| 831 | } |
| 832 | |
| 833 | /* |
| 834 | * Remove channel using key from registry and free memory. |
| 835 | */ |
| 836 | void ust_registry_channel_del_free(struct ust_registry_session *session, |
| 837 | uint64_t key, bool notif) |
| 838 | { |
| 839 | struct lttng_ht_iter iter; |
| 840 | struct ust_registry_channel *chan; |
| 841 | int ret; |
| 842 | |
| 843 | assert(session); |
| 844 | |
| 845 | rcu_read_lock(); |
| 846 | chan = ust_registry_channel_find(session, key); |
| 847 | if (!chan) { |
| 848 | rcu_read_unlock(); |
| 849 | goto end; |
| 850 | } |
| 851 | |
| 852 | iter.iter.node = &chan->node.node; |
| 853 | ret = lttng_ht_del(session->channels, &iter); |
| 854 | assert(!ret); |
| 855 | rcu_read_unlock(); |
| 856 | destroy_channel(chan, notif); |
| 857 | |
| 858 | end: |
| 859 | return; |
| 860 | } |
| 861 | |
| 862 | /* |
| 863 | * Initialize registry with default values and set the newly allocated session |
| 864 | * pointer to sessionp. |
| 865 | * |
| 866 | * Return 0 on success and sessionp is set or else return -1 and sessionp is |
| 867 | * kept untouched. |
| 868 | */ |
| 869 | int ust_registry_session_init(struct ust_registry_session **sessionp, |
| 870 | struct ust_app *app, |
| 871 | uint32_t bits_per_long, |
| 872 | uint32_t uint8_t_alignment, |
| 873 | uint32_t uint16_t_alignment, |
| 874 | uint32_t uint32_t_alignment, |
| 875 | uint32_t uint64_t_alignment, |
| 876 | uint32_t long_alignment, |
| 877 | int byte_order, |
| 878 | uint32_t major, |
| 879 | uint32_t minor, |
| 880 | const char *root_shm_path, |
| 881 | const char *shm_path, |
| 882 | uid_t euid, |
| 883 | gid_t egid) |
| 884 | { |
| 885 | int ret; |
| 886 | struct ust_registry_session *session; |
| 887 | |
| 888 | assert(sessionp); |
| 889 | |
| 890 | session = zmalloc(sizeof(*session)); |
| 891 | if (!session) { |
| 892 | PERROR("zmalloc ust registry session"); |
| 893 | goto error_alloc; |
| 894 | } |
| 895 | |
| 896 | pthread_mutex_init(&session->lock, NULL); |
| 897 | session->bits_per_long = bits_per_long; |
| 898 | session->uint8_t_alignment = uint8_t_alignment; |
| 899 | session->uint16_t_alignment = uint16_t_alignment; |
| 900 | session->uint32_t_alignment = uint32_t_alignment; |
| 901 | session->uint64_t_alignment = uint64_t_alignment; |
| 902 | session->long_alignment = long_alignment; |
| 903 | session->byte_order = byte_order; |
| 904 | session->metadata_fd = -1; |
| 905 | session->uid = euid; |
| 906 | session->gid = egid; |
| 907 | session->next_enum_id = 0; |
| 908 | session->major = major; |
| 909 | session->minor = minor; |
| 910 | strncpy(session->root_shm_path, root_shm_path, |
| 911 | sizeof(session->root_shm_path)); |
| 912 | session->root_shm_path[sizeof(session->root_shm_path) - 1] = '\0'; |
| 913 | if (shm_path[0]) { |
| 914 | strncpy(session->shm_path, shm_path, |
| 915 | sizeof(session->shm_path)); |
| 916 | session->shm_path[sizeof(session->shm_path) - 1] = '\0'; |
| 917 | strncpy(session->metadata_path, shm_path, |
| 918 | sizeof(session->metadata_path)); |
| 919 | session->metadata_path[sizeof(session->metadata_path) - 1] = '\0'; |
| 920 | strncat(session->metadata_path, "/metadata", |
| 921 | sizeof(session->metadata_path) |
| 922 | - strlen(session->metadata_path) - 1); |
| 923 | } |
| 924 | if (session->shm_path[0]) { |
| 925 | ret = run_as_mkdir_recursive(session->shm_path, |
| 926 | S_IRWXU | S_IRWXG, |
| 927 | euid, egid); |
| 928 | if (ret) { |
| 929 | PERROR("run_as_mkdir_recursive"); |
| 930 | goto error; |
| 931 | } |
| 932 | } |
| 933 | if (session->metadata_path[0]) { |
| 934 | /* Create metadata file */ |
| 935 | ret = run_as_open(session->metadata_path, |
| 936 | O_WRONLY | O_CREAT | O_EXCL, |
| 937 | S_IRUSR | S_IWUSR, euid, egid); |
| 938 | if (ret < 0) { |
| 939 | PERROR("Opening metadata file"); |
| 940 | goto error; |
| 941 | } |
| 942 | session->metadata_fd = ret; |
| 943 | } |
| 944 | |
| 945 | session->enums = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); |
| 946 | if (!session->enums) { |
| 947 | ERR("Failed to create enums hash table"); |
| 948 | goto error; |
| 949 | } |
| 950 | /* hash/match functions are specified at call site. */ |
| 951 | session->enums->match_fct = NULL; |
| 952 | session->enums->hash_fct = NULL; |
| 953 | |
| 954 | session->channels = lttng_ht_new(0, LTTNG_HT_TYPE_U64); |
| 955 | if (!session->channels) { |
| 956 | goto error; |
| 957 | } |
| 958 | |
| 959 | ret = lttng_uuid_generate(session->uuid); |
| 960 | if (ret) { |
| 961 | ERR("Failed to generate UST uuid (errno = %d)", ret); |
| 962 | goto error; |
| 963 | } |
| 964 | |
| 965 | pthread_mutex_lock(&session->lock); |
| 966 | ret = ust_metadata_session_statedump(session, app, major, minor); |
| 967 | pthread_mutex_unlock(&session->lock); |
| 968 | if (ret) { |
| 969 | ERR("Failed to generate session metadata (errno = %d)", ret); |
| 970 | goto error; |
| 971 | } |
| 972 | |
| 973 | *sessionp = session; |
| 974 | |
| 975 | return 0; |
| 976 | |
| 977 | error: |
| 978 | ust_registry_session_destroy(session); |
| 979 | free(session); |
| 980 | error_alloc: |
| 981 | return -1; |
| 982 | } |
| 983 | |
| 984 | /* |
| 985 | * Destroy session registry. This does NOT free the given pointer since it |
| 986 | * might get passed as a reference. The registry lock should NOT be acquired. |
| 987 | */ |
| 988 | void ust_registry_session_destroy(struct ust_registry_session *reg) |
| 989 | { |
| 990 | int ret; |
| 991 | struct lttng_ht_iter iter; |
| 992 | struct ust_registry_channel *chan; |
| 993 | struct ust_registry_enum *reg_enum; |
| 994 | |
| 995 | if (!reg) { |
| 996 | return; |
| 997 | } |
| 998 | |
| 999 | /* On error, EBUSY can be returned if lock. Code flow error. */ |
| 1000 | ret = pthread_mutex_destroy(®->lock); |
| 1001 | assert(!ret); |
| 1002 | |
| 1003 | if (reg->channels) { |
| 1004 | rcu_read_lock(); |
| 1005 | /* Destroy all event associated with this registry. */ |
| 1006 | cds_lfht_for_each_entry(reg->channels->ht, &iter.iter, chan, |
| 1007 | node.node) { |
| 1008 | /* Delete the node from the ht and free it. */ |
| 1009 | ret = lttng_ht_del(reg->channels, &iter); |
| 1010 | assert(!ret); |
| 1011 | destroy_channel(chan, true); |
| 1012 | } |
| 1013 | rcu_read_unlock(); |
| 1014 | ht_cleanup_push(reg->channels); |
| 1015 | } |
| 1016 | |
| 1017 | free(reg->metadata); |
| 1018 | if (reg->metadata_fd >= 0) { |
| 1019 | ret = close(reg->metadata_fd); |
| 1020 | if (ret) { |
| 1021 | PERROR("close"); |
| 1022 | } |
| 1023 | ret = run_as_unlink(reg->metadata_path, |
| 1024 | reg->uid, reg->gid); |
| 1025 | if (ret) { |
| 1026 | PERROR("unlink"); |
| 1027 | } |
| 1028 | } |
| 1029 | if (reg->root_shm_path[0]) { |
| 1030 | /* |
| 1031 | * Try deleting the directory hierarchy. |
| 1032 | */ |
| 1033 | (void) run_as_rmdir_recursive(reg->root_shm_path, |
| 1034 | reg->uid, reg->gid); |
| 1035 | } |
| 1036 | /* Destroy the enum hash table */ |
| 1037 | if (reg->enums) { |
| 1038 | rcu_read_lock(); |
| 1039 | /* Destroy all enum entries associated with this registry. */ |
| 1040 | cds_lfht_for_each_entry(reg->enums->ht, &iter.iter, reg_enum, |
| 1041 | node.node) { |
| 1042 | ust_registry_destroy_enum(reg, reg_enum); |
| 1043 | } |
| 1044 | rcu_read_unlock(); |
| 1045 | ht_cleanup_push(reg->enums); |
| 1046 | } |
| 1047 | } |