| 1 | /* |
| 2 | * Copyright (C) 2013 David Goulet <dgoulet@efficios.com> |
| 3 | * |
| 4 | * SPDX-License-Identifier: GPL-2.0-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #define _LGPL_SOURCE |
| 9 | #include <inttypes.h> |
| 10 | |
| 11 | #include <common/common.hpp> |
| 12 | #include <common/hashtable/utils.hpp> |
| 13 | #include <common/exception.hpp> |
| 14 | #include <lttng/lttng.h> |
| 15 | |
| 16 | #include "ust-registry.hpp" |
| 17 | #include "ust-app.hpp" |
| 18 | #include "ust-field-utils.hpp" |
| 19 | #include "utils.hpp" |
| 20 | #include "lttng-sessiond.hpp" |
| 21 | #include "notification-thread-commands.hpp" |
| 22 | |
| 23 | /* |
| 24 | * Hash table match function for event in the registry. |
| 25 | */ |
| 26 | static int ht_match_event(struct cds_lfht_node *node, const void *_key) |
| 27 | { |
| 28 | const struct ust_registry_event *key; |
| 29 | struct ust_registry_event *event; |
| 30 | |
| 31 | LTTNG_ASSERT(node); |
| 32 | LTTNG_ASSERT(_key); |
| 33 | |
| 34 | event = caa_container_of(node, struct ust_registry_event, node.node); |
| 35 | LTTNG_ASSERT(event); |
| 36 | key = (ust_registry_event *) _key; |
| 37 | |
| 38 | /* It has to be a perfect match. First, compare the event names. */ |
| 39 | if (strncmp(event->name, key->name, sizeof(event->name))) { |
| 40 | goto no_match; |
| 41 | } |
| 42 | |
| 43 | /* Compare log levels. */ |
| 44 | if (event->loglevel_value != key->loglevel_value) { |
| 45 | goto no_match; |
| 46 | } |
| 47 | |
| 48 | /* Compare the arrays of fields. */ |
| 49 | if (!match_lttng_ust_ctl_field_array(event->fields, event->nr_fields, |
| 50 | key->fields, key->nr_fields)) { |
| 51 | goto no_match; |
| 52 | } |
| 53 | |
| 54 | /* Compare model URI. */ |
| 55 | if (event->model_emf_uri != NULL && key->model_emf_uri == NULL) { |
| 56 | goto no_match; |
| 57 | } else if(event->model_emf_uri == NULL && key->model_emf_uri != NULL) { |
| 58 | goto no_match; |
| 59 | } else if (event->model_emf_uri != NULL && key->model_emf_uri != NULL) { |
| 60 | if (strcmp(event->model_emf_uri, key->model_emf_uri)) { |
| 61 | goto no_match; |
| 62 | } |
| 63 | } |
| 64 | |
| 65 | /* Match */ |
| 66 | return 1; |
| 67 | |
| 68 | no_match: |
| 69 | return 0; |
| 70 | } |
| 71 | |
| 72 | static unsigned long ht_hash_event(const void *_key, unsigned long seed) |
| 73 | { |
| 74 | uint64_t hashed_key; |
| 75 | const struct ust_registry_event *key = (ust_registry_event *) _key; |
| 76 | |
| 77 | LTTNG_ASSERT(key); |
| 78 | |
| 79 | hashed_key = (uint64_t) hash_key_str(key->name, seed); |
| 80 | |
| 81 | return hash_key_u64(&hashed_key, seed); |
| 82 | } |
| 83 | |
| 84 | static int compare_enums(const struct ust_registry_enum *reg_enum_a, |
| 85 | const struct ust_registry_enum *reg_enum_b) |
| 86 | { |
| 87 | int ret = 0; |
| 88 | size_t i; |
| 89 | |
| 90 | LTTNG_ASSERT(strcmp(reg_enum_a->name, reg_enum_b->name) == 0); |
| 91 | if (reg_enum_a->nr_entries != reg_enum_b->nr_entries) { |
| 92 | ret = -1; |
| 93 | goto end; |
| 94 | } |
| 95 | for (i = 0; i < reg_enum_a->nr_entries; i++) { |
| 96 | const struct lttng_ust_ctl_enum_entry *entries_a, *entries_b; |
| 97 | |
| 98 | entries_a = ®_enum_a->entries[i]; |
| 99 | entries_b = ®_enum_b->entries[i]; |
| 100 | if (entries_a->start.value != entries_b->start.value) { |
| 101 | ret = -1; |
| 102 | goto end; |
| 103 | } |
| 104 | if (entries_a->end.value != entries_b->end.value) { |
| 105 | ret = -1; |
| 106 | goto end; |
| 107 | } |
| 108 | if (entries_a->start.signedness != entries_b->start.signedness) { |
| 109 | ret = -1; |
| 110 | goto end; |
| 111 | } |
| 112 | if (entries_a->end.signedness != entries_b->end.signedness) { |
| 113 | ret = -1; |
| 114 | goto end; |
| 115 | } |
| 116 | |
| 117 | if (strcmp(entries_a->string, entries_b->string)) { |
| 118 | ret = -1; |
| 119 | goto end; |
| 120 | } |
| 121 | } |
| 122 | end: |
| 123 | return ret; |
| 124 | } |
| 125 | |
| 126 | /* |
| 127 | * Hash table match function for enumerations in the session. Match is |
| 128 | * performed on enumeration name, and confirmed by comparing the enum |
| 129 | * entries. |
| 130 | */ |
| 131 | static int ht_match_enum(struct cds_lfht_node *node, const void *_key) |
| 132 | { |
| 133 | struct ust_registry_enum *_enum; |
| 134 | const struct ust_registry_enum *key; |
| 135 | |
| 136 | LTTNG_ASSERT(node); |
| 137 | LTTNG_ASSERT(_key); |
| 138 | |
| 139 | _enum = caa_container_of(node, struct ust_registry_enum, |
| 140 | node.node); |
| 141 | LTTNG_ASSERT(_enum); |
| 142 | key = (ust_registry_enum *) _key; |
| 143 | |
| 144 | if (strncmp(_enum->name, key->name, LTTNG_UST_ABI_SYM_NAME_LEN)) { |
| 145 | goto no_match; |
| 146 | } |
| 147 | if (compare_enums(_enum, key)) { |
| 148 | goto no_match; |
| 149 | } |
| 150 | |
| 151 | /* Match. */ |
| 152 | return 1; |
| 153 | |
| 154 | no_match: |
| 155 | return 0; |
| 156 | } |
| 157 | |
| 158 | /* |
| 159 | * Hash table match function for enumerations in the session. Match is |
| 160 | * performed by enumeration ID. |
| 161 | */ |
| 162 | static int ht_match_enum_id(struct cds_lfht_node *node, const void *_key) |
| 163 | { |
| 164 | struct ust_registry_enum *_enum; |
| 165 | const struct ust_registry_enum *key = (ust_registry_enum *) _key; |
| 166 | |
| 167 | LTTNG_ASSERT(node); |
| 168 | LTTNG_ASSERT(_key); |
| 169 | |
| 170 | _enum = caa_container_of(node, struct ust_registry_enum, node.node); |
| 171 | LTTNG_ASSERT(_enum); |
| 172 | |
| 173 | if (_enum->id != key->id) { |
| 174 | goto no_match; |
| 175 | } |
| 176 | |
| 177 | /* Match. */ |
| 178 | return 1; |
| 179 | |
| 180 | no_match: |
| 181 | return 0; |
| 182 | } |
| 183 | |
| 184 | /* |
| 185 | * Hash table hash function for enumerations in the session. The |
| 186 | * enumeration name is used for hashing. |
| 187 | */ |
| 188 | static unsigned long ht_hash_enum(void *_key, unsigned long seed) |
| 189 | { |
| 190 | struct ust_registry_enum *key = (ust_registry_enum *) _key; |
| 191 | |
| 192 | LTTNG_ASSERT(key); |
| 193 | return hash_key_str(key->name, seed); |
| 194 | } |
| 195 | |
| 196 | /* |
| 197 | * Return negative value on error, 0 if OK. |
| 198 | * |
| 199 | * TODO: we could add stricter verification of more types to catch |
| 200 | * errors in liblttng-ust implementation earlier than consumption by the |
| 201 | * trace reader. |
| 202 | */ |
| 203 | static |
| 204 | int validate_event_field(struct lttng_ust_ctl_field *field, |
| 205 | const char *event_name, |
| 206 | struct ust_app *app) |
| 207 | { |
| 208 | int ret = 0; |
| 209 | |
| 210 | switch(field->type.atype) { |
| 211 | case lttng_ust_ctl_atype_integer: |
| 212 | case lttng_ust_ctl_atype_enum: |
| 213 | case lttng_ust_ctl_atype_array: |
| 214 | case lttng_ust_ctl_atype_sequence: |
| 215 | case lttng_ust_ctl_atype_string: |
| 216 | case lttng_ust_ctl_atype_variant: |
| 217 | case lttng_ust_ctl_atype_array_nestable: |
| 218 | case lttng_ust_ctl_atype_sequence_nestable: |
| 219 | case lttng_ust_ctl_atype_enum_nestable: |
| 220 | case lttng_ust_ctl_atype_variant_nestable: |
| 221 | break; |
| 222 | case lttng_ust_ctl_atype_struct: |
| 223 | if (field->type.u.legacy._struct.nr_fields != 0) { |
| 224 | WARN("Unsupported non-empty struct field."); |
| 225 | ret = -EINVAL; |
| 226 | goto end; |
| 227 | } |
| 228 | break; |
| 229 | case lttng_ust_ctl_atype_struct_nestable: |
| 230 | if (field->type.u.struct_nestable.nr_fields != 0) { |
| 231 | WARN("Unsupported non-empty struct field."); |
| 232 | ret = -EINVAL; |
| 233 | goto end; |
| 234 | } |
| 235 | break; |
| 236 | |
| 237 | case lttng_ust_ctl_atype_float: |
| 238 | switch (field->type.u._float.mant_dig) { |
| 239 | case 0: |
| 240 | WARN("UST application '%s' (pid: %d) has unknown float mantissa '%u' " |
| 241 | "in field '%s', rejecting event '%s'", |
| 242 | app->name, app->pid, |
| 243 | field->type.u._float.mant_dig, |
| 244 | field->name, |
| 245 | event_name); |
| 246 | ret = -EINVAL; |
| 247 | goto end; |
| 248 | default: |
| 249 | break; |
| 250 | } |
| 251 | break; |
| 252 | |
| 253 | default: |
| 254 | ret = -ENOENT; |
| 255 | goto end; |
| 256 | } |
| 257 | end: |
| 258 | return ret; |
| 259 | } |
| 260 | |
| 261 | static |
| 262 | int validate_event_fields(size_t nr_fields, struct lttng_ust_ctl_field *fields, |
| 263 | const char *event_name, struct ust_app *app) |
| 264 | { |
| 265 | unsigned int i; |
| 266 | |
| 267 | for (i = 0; i < nr_fields; i++) { |
| 268 | if (validate_event_field(&fields[i], event_name, app) < 0) |
| 269 | return -EINVAL; |
| 270 | } |
| 271 | return 0; |
| 272 | } |
| 273 | |
| 274 | /* |
| 275 | * Allocate event and initialize it. This does NOT set a valid event id from a |
| 276 | * registry. |
| 277 | */ |
| 278 | static struct ust_registry_event *alloc_event(int session_objd, |
| 279 | int channel_objd, char *name, char *sig, size_t nr_fields, |
| 280 | struct lttng_ust_ctl_field *fields, int loglevel_value, |
| 281 | char *model_emf_uri, struct ust_app *app) |
| 282 | { |
| 283 | struct ust_registry_event *event = NULL; |
| 284 | |
| 285 | /* |
| 286 | * Ensure that the field content is valid. |
| 287 | */ |
| 288 | if (validate_event_fields(nr_fields, fields, name, app) < 0) { |
| 289 | return NULL; |
| 290 | } |
| 291 | |
| 292 | event = zmalloc<ust_registry_event>(); |
| 293 | if (!event) { |
| 294 | PERROR("zmalloc ust registry event"); |
| 295 | goto error; |
| 296 | } |
| 297 | |
| 298 | event->session_objd = session_objd; |
| 299 | event->channel_objd = channel_objd; |
| 300 | /* Allocated by ustctl. */ |
| 301 | event->signature = sig; |
| 302 | event->nr_fields = nr_fields; |
| 303 | event->fields = fields; |
| 304 | event->loglevel_value = loglevel_value; |
| 305 | event->model_emf_uri = model_emf_uri; |
| 306 | if (name) { |
| 307 | /* Copy event name and force NULL byte. */ |
| 308 | strncpy(event->name, name, sizeof(event->name)); |
| 309 | event->name[sizeof(event->name) - 1] = '\0'; |
| 310 | } |
| 311 | cds_lfht_node_init(&event->node.node); |
| 312 | |
| 313 | error: |
| 314 | return event; |
| 315 | } |
| 316 | |
| 317 | /* |
| 318 | * Free event data structure. This does NOT delete it from any hash table. It's |
| 319 | * safe to pass a NULL pointer. This should be called inside a call RCU if the |
| 320 | * event is previously deleted from a rcu hash table. |
| 321 | */ |
| 322 | static void destroy_event(struct ust_registry_event *event) |
| 323 | { |
| 324 | if (!event) { |
| 325 | return; |
| 326 | } |
| 327 | |
| 328 | free(event->fields); |
| 329 | free(event->model_emf_uri); |
| 330 | free(event->signature); |
| 331 | free(event); |
| 332 | } |
| 333 | |
| 334 | /* |
| 335 | * Destroy event function call of the call RCU. |
| 336 | */ |
| 337 | static void destroy_event_rcu(struct rcu_head *head) |
| 338 | { |
| 339 | struct lttng_ht_node_u64 *node = |
| 340 | caa_container_of(head, struct lttng_ht_node_u64, head); |
| 341 | struct ust_registry_event *event = |
| 342 | caa_container_of(node, struct ust_registry_event, node); |
| 343 | |
| 344 | destroy_event(event); |
| 345 | } |
| 346 | |
| 347 | /* |
| 348 | * Find an event using the name and signature in the given registry. RCU read |
| 349 | * side lock MUST be acquired before calling this function and as long as the |
| 350 | * event reference is kept by the caller. |
| 351 | * |
| 352 | * On success, the event pointer is returned else NULL. |
| 353 | */ |
| 354 | struct ust_registry_event *ust_registry_find_event( |
| 355 | struct ust_registry_channel *chan, char *name, char *sig) |
| 356 | { |
| 357 | struct lttng_ht_node_u64 *node; |
| 358 | struct lttng_ht_iter iter; |
| 359 | struct ust_registry_event *event = NULL; |
| 360 | struct ust_registry_event key; |
| 361 | |
| 362 | LTTNG_ASSERT(chan); |
| 363 | LTTNG_ASSERT(name); |
| 364 | LTTNG_ASSERT(sig); |
| 365 | ASSERT_RCU_READ_LOCKED(); |
| 366 | |
| 367 | /* Setup key for the match function. */ |
| 368 | strncpy(key.name, name, sizeof(key.name)); |
| 369 | key.name[sizeof(key.name) - 1] = '\0'; |
| 370 | key.signature = sig; |
| 371 | |
| 372 | cds_lfht_lookup(chan->events->ht, chan->events->hash_fct(&key, lttng_ht_seed), |
| 373 | chan->events->match_fct, &key, &iter.iter); |
| 374 | node = lttng_ht_iter_get_node_u64(&iter); |
| 375 | if (!node) { |
| 376 | goto end; |
| 377 | } |
| 378 | event = caa_container_of(node, struct ust_registry_event, node); |
| 379 | |
| 380 | end: |
| 381 | return event; |
| 382 | } |
| 383 | |
| 384 | /* |
| 385 | * Create a ust_registry_event from the given parameters and add it to the |
| 386 | * registry hash table. If event_id is valid, it is set with the newly created |
| 387 | * event id. |
| 388 | * |
| 389 | * On success, return 0 else a negative value. The created event MUST be unique |
| 390 | * so on duplicate entry -EINVAL is returned. On error, event_id is untouched. |
| 391 | * |
| 392 | * Should be called with session registry mutex held. |
| 393 | */ |
| 394 | int ust_registry_create_event(ust_registry_session *session, |
| 395 | uint64_t chan_key, int session_objd, int channel_objd, char *name, |
| 396 | char *sig, size_t nr_fields, struct lttng_ust_ctl_field *fields, |
| 397 | int loglevel_value, char *model_emf_uri, int buffer_type, |
| 398 | uint32_t *event_id_p, struct ust_app *app) |
| 399 | { |
| 400 | int ret; |
| 401 | uint32_t event_id; |
| 402 | struct cds_lfht_node *nptr; |
| 403 | struct ust_registry_event *event = NULL; |
| 404 | struct ust_registry_channel *chan; |
| 405 | |
| 406 | LTTNG_ASSERT(session); |
| 407 | LTTNG_ASSERT(name); |
| 408 | LTTNG_ASSERT(sig); |
| 409 | LTTNG_ASSERT(event_id_p); |
| 410 | |
| 411 | rcu_read_lock(); |
| 412 | |
| 413 | /* |
| 414 | * This should not happen but since it comes from the UST tracer, an |
| 415 | * external party, don't assert and simply validate values. |
| 416 | */ |
| 417 | if (session_objd < 0 || channel_objd < 0) { |
| 418 | ret = -EINVAL; |
| 419 | goto error_free; |
| 420 | } |
| 421 | |
| 422 | chan = ust_registry_channel_find(session, chan_key); |
| 423 | if (!chan) { |
| 424 | ret = -EINVAL; |
| 425 | goto error_free; |
| 426 | } |
| 427 | |
| 428 | /* Check if we've reached the maximum possible id. */ |
| 429 | if (ust_registry_is_max_id(chan->used_event_id)) { |
| 430 | ret = -ENOENT; |
| 431 | goto error_free; |
| 432 | } |
| 433 | |
| 434 | event = alloc_event(session_objd, channel_objd, name, sig, nr_fields, |
| 435 | fields, loglevel_value, model_emf_uri, app); |
| 436 | if (!event) { |
| 437 | ret = -ENOMEM; |
| 438 | goto error_free; |
| 439 | } |
| 440 | |
| 441 | DBG3("UST registry creating event with event: %s, sig: %s, id: %u, " |
| 442 | "chan_objd: %u, sess_objd: %u, chan_id: %u", event->name, |
| 443 | event->signature, event->id, event->channel_objd, |
| 444 | event->session_objd, chan->chan_id); |
| 445 | |
| 446 | /* |
| 447 | * This is an add unique with a custom match function for event. The node |
| 448 | * are matched using the event name and signature. |
| 449 | */ |
| 450 | nptr = cds_lfht_add_unique(chan->events->ht, chan->events->hash_fct(event, |
| 451 | lttng_ht_seed), chan->events->match_fct, event, &event->node.node); |
| 452 | if (nptr != &event->node.node) { |
| 453 | if (buffer_type == LTTNG_BUFFER_PER_UID) { |
| 454 | /* |
| 455 | * This is normal, we just have to send the event id of the |
| 456 | * returned node and make sure we destroy the previously allocated |
| 457 | * event object. |
| 458 | */ |
| 459 | destroy_event(event); |
| 460 | event = caa_container_of(nptr, struct ust_registry_event, |
| 461 | node.node); |
| 462 | LTTNG_ASSERT(event); |
| 463 | event_id = event->id; |
| 464 | } else { |
| 465 | ERR("UST registry create event add unique failed for event: %s, " |
| 466 | "sig: %s, id: %u, chan_objd: %u, sess_objd: %u", |
| 467 | event->name, event->signature, event->id, |
| 468 | event->channel_objd, event->session_objd); |
| 469 | ret = -EINVAL; |
| 470 | goto error_unlock; |
| 471 | } |
| 472 | } else { |
| 473 | /* Request next event id if the node was successfully added. */ |
| 474 | event_id = event->id = ust_registry_get_next_event_id(chan); |
| 475 | } |
| 476 | |
| 477 | *event_id_p = event_id; |
| 478 | |
| 479 | if (!event->metadata_dumped) { |
| 480 | /* Append to metadata */ |
| 481 | ret = ust_metadata_event_statedump(session, chan, event); |
| 482 | if (ret) { |
| 483 | ERR("Error appending event metadata (errno = %d)", ret); |
| 484 | rcu_read_unlock(); |
| 485 | return ret; |
| 486 | } |
| 487 | } |
| 488 | |
| 489 | rcu_read_unlock(); |
| 490 | return 0; |
| 491 | |
| 492 | error_free: |
| 493 | free(sig); |
| 494 | free(fields); |
| 495 | free(model_emf_uri); |
| 496 | error_unlock: |
| 497 | rcu_read_unlock(); |
| 498 | destroy_event(event); |
| 499 | return ret; |
| 500 | } |
| 501 | |
| 502 | /* |
| 503 | * For a given event in a registry, delete the entry and destroy the event. |
| 504 | * This MUST be called within a RCU read side lock section. |
| 505 | */ |
| 506 | void ust_registry_destroy_event(struct ust_registry_channel *chan, |
| 507 | struct ust_registry_event *event) |
| 508 | { |
| 509 | int ret; |
| 510 | struct lttng_ht_iter iter; |
| 511 | |
| 512 | LTTNG_ASSERT(chan); |
| 513 | LTTNG_ASSERT(event); |
| 514 | ASSERT_RCU_READ_LOCKED(); |
| 515 | |
| 516 | /* Delete the node first. */ |
| 517 | iter.iter.node = &event->node.node; |
| 518 | ret = lttng_ht_del(chan->events, &iter); |
| 519 | LTTNG_ASSERT(!ret); |
| 520 | |
| 521 | call_rcu(&event->node.head, destroy_event_rcu); |
| 522 | |
| 523 | return; |
| 524 | } |
| 525 | |
| 526 | static void destroy_enum(struct ust_registry_enum *reg_enum) |
| 527 | { |
| 528 | if (!reg_enum) { |
| 529 | return; |
| 530 | } |
| 531 | free(reg_enum->entries); |
| 532 | free(reg_enum); |
| 533 | } |
| 534 | |
| 535 | static void destroy_enum_rcu(struct rcu_head *head) |
| 536 | { |
| 537 | struct ust_registry_enum *reg_enum = |
| 538 | caa_container_of(head, struct ust_registry_enum, rcu_head); |
| 539 | |
| 540 | destroy_enum(reg_enum); |
| 541 | } |
| 542 | |
| 543 | /* |
| 544 | * Lookup enumeration by name and comparing enumeration entries. |
| 545 | * Needs to be called from RCU read-side critical section. |
| 546 | */ |
| 547 | static struct ust_registry_enum *ust_registry_lookup_enum( |
| 548 | ust_registry_session *session, |
| 549 | const struct ust_registry_enum *reg_enum_lookup) |
| 550 | { |
| 551 | struct ust_registry_enum *reg_enum = NULL; |
| 552 | struct lttng_ht_node_str *node; |
| 553 | struct lttng_ht_iter iter; |
| 554 | |
| 555 | ASSERT_RCU_READ_LOCKED(); |
| 556 | |
| 557 | cds_lfht_lookup(session->_enums->ht, |
| 558 | ht_hash_enum((void *) reg_enum_lookup, lttng_ht_seed), |
| 559 | ht_match_enum, reg_enum_lookup, &iter.iter); |
| 560 | node = lttng_ht_iter_get_node_str(&iter); |
| 561 | if (!node) { |
| 562 | goto end; |
| 563 | } |
| 564 | reg_enum = caa_container_of(node, struct ust_registry_enum, node); |
| 565 | end: |
| 566 | return reg_enum; |
| 567 | } |
| 568 | |
| 569 | /* |
| 570 | * Lookup enumeration by enum ID. |
| 571 | * Needs to be called from RCU read-side critical section. |
| 572 | */ |
| 573 | struct ust_registry_enum * |
| 574 | ust_registry_lookup_enum_by_id(ust_registry_session *session, |
| 575 | const char *enum_name, uint64_t enum_id) |
| 576 | { |
| 577 | struct ust_registry_enum *reg_enum = NULL; |
| 578 | struct lttng_ht_node_str *node; |
| 579 | struct lttng_ht_iter iter; |
| 580 | struct ust_registry_enum reg_enum_lookup; |
| 581 | |
| 582 | ASSERT_RCU_READ_LOCKED(); |
| 583 | |
| 584 | memset(®_enum_lookup, 0, sizeof(reg_enum_lookup)); |
| 585 | strncpy(reg_enum_lookup.name, enum_name, LTTNG_UST_ABI_SYM_NAME_LEN); |
| 586 | reg_enum_lookup.name[LTTNG_UST_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 587 | reg_enum_lookup.id = enum_id; |
| 588 | cds_lfht_lookup(session->_enums->ht, |
| 589 | ht_hash_enum((void *) ®_enum_lookup, lttng_ht_seed), |
| 590 | ht_match_enum_id, ®_enum_lookup, &iter.iter); |
| 591 | node = lttng_ht_iter_get_node_str(&iter); |
| 592 | if (!node) { |
| 593 | goto end; |
| 594 | } |
| 595 | reg_enum = caa_container_of(node, struct ust_registry_enum, node); |
| 596 | end: |
| 597 | return reg_enum; |
| 598 | } |
| 599 | |
| 600 | /* |
| 601 | * Create a ust_registry_enum from the given parameters and add it to the |
| 602 | * registry hash table, or find it if already there. |
| 603 | * |
| 604 | * On success, return 0 else a negative value. |
| 605 | * |
| 606 | * Should be called with session registry mutex held. |
| 607 | * |
| 608 | * We receive ownership of entries. |
| 609 | */ |
| 610 | int ust_registry_create_or_find_enum(ust_registry_session *session, |
| 611 | int session_objd, char *enum_name, |
| 612 | struct lttng_ust_ctl_enum_entry *entries, size_t nr_entries, |
| 613 | uint64_t *enum_id) |
| 614 | { |
| 615 | int ret = 0; |
| 616 | struct cds_lfht_node *nodep; |
| 617 | struct ust_registry_enum *reg_enum = NULL, *old_reg_enum; |
| 618 | |
| 619 | LTTNG_ASSERT(session); |
| 620 | LTTNG_ASSERT(enum_name); |
| 621 | |
| 622 | rcu_read_lock(); |
| 623 | |
| 624 | /* |
| 625 | * This should not happen but since it comes from the UST tracer, an |
| 626 | * external party, don't assert and simply validate values. |
| 627 | */ |
| 628 | if (session_objd < 0) { |
| 629 | ret = -EINVAL; |
| 630 | goto end; |
| 631 | } |
| 632 | |
| 633 | /* Check if the enumeration was already dumped */ |
| 634 | reg_enum = zmalloc<ust_registry_enum>(); |
| 635 | if (!reg_enum) { |
| 636 | PERROR("zmalloc ust registry enumeration"); |
| 637 | ret = -ENOMEM; |
| 638 | goto end; |
| 639 | } |
| 640 | strncpy(reg_enum->name, enum_name, LTTNG_UST_ABI_SYM_NAME_LEN); |
| 641 | reg_enum->name[LTTNG_UST_ABI_SYM_NAME_LEN - 1] = '\0'; |
| 642 | /* entries will be owned by reg_enum. */ |
| 643 | reg_enum->entries = entries; |
| 644 | reg_enum->nr_entries = nr_entries; |
| 645 | entries = NULL; |
| 646 | |
| 647 | old_reg_enum = ust_registry_lookup_enum(session, reg_enum); |
| 648 | if (old_reg_enum) { |
| 649 | DBG("enum %s already in sess_objd: %u", enum_name, session_objd); |
| 650 | /* Fall through. Use prior enum. */ |
| 651 | destroy_enum(reg_enum); |
| 652 | reg_enum = old_reg_enum; |
| 653 | } else { |
| 654 | DBG("UST registry creating enum: %s, sess_objd: %u", |
| 655 | enum_name, session_objd); |
| 656 | if (session->_next_enum_id == -1ULL) { |
| 657 | ret = -EOVERFLOW; |
| 658 | destroy_enum(reg_enum); |
| 659 | goto end; |
| 660 | } |
| 661 | reg_enum->id = session->_next_enum_id++; |
| 662 | cds_lfht_node_init(®_enum->node.node); |
| 663 | nodep = cds_lfht_add_unique(session->_enums->ht, |
| 664 | ht_hash_enum(reg_enum, lttng_ht_seed), |
| 665 | ht_match_enum_id, reg_enum, |
| 666 | ®_enum->node.node); |
| 667 | LTTNG_ASSERT(nodep == ®_enum->node.node); |
| 668 | } |
| 669 | DBG("UST registry reply with enum %s with id %" PRIu64 " in sess_objd: %u", |
| 670 | enum_name, reg_enum->id, session_objd); |
| 671 | *enum_id = reg_enum->id; |
| 672 | end: |
| 673 | free(entries); |
| 674 | rcu_read_unlock(); |
| 675 | return ret; |
| 676 | } |
| 677 | |
| 678 | /* |
| 679 | * For a given enumeration in a registry, delete the entry and destroy |
| 680 | * the enumeration. |
| 681 | * This MUST be called within a RCU read side lock section. |
| 682 | */ |
| 683 | void ust_registry_destroy_enum(ust_registry_session *reg_session, |
| 684 | struct ust_registry_enum *reg_enum) |
| 685 | { |
| 686 | int ret; |
| 687 | struct lttng_ht_iter iter; |
| 688 | |
| 689 | LTTNG_ASSERT(reg_session); |
| 690 | LTTNG_ASSERT(reg_enum); |
| 691 | ASSERT_RCU_READ_LOCKED(); |
| 692 | |
| 693 | /* Delete the node first. */ |
| 694 | iter.iter.node = ®_enum->node.node; |
| 695 | ret = lttng_ht_del(reg_session->_enums.get(), &iter); |
| 696 | LTTNG_ASSERT(!ret); |
| 697 | call_rcu(®_enum->rcu_head, destroy_enum_rcu); |
| 698 | } |
| 699 | |
| 700 | static |
| 701 | void destroy_channel_rcu(struct rcu_head *head) |
| 702 | { |
| 703 | struct ust_registry_channel *chan = |
| 704 | caa_container_of(head, struct ust_registry_channel, rcu_head); |
| 705 | |
| 706 | if (chan->events) { |
| 707 | lttng_ht_destroy(chan->events); |
| 708 | } |
| 709 | |
| 710 | free(chan->ctx_fields); |
| 711 | free(chan); |
| 712 | } |
| 713 | |
| 714 | /* |
| 715 | * Destroy every element of the registry and free the memory. This does NOT |
| 716 | * free the registry pointer since it might not have been allocated before so |
| 717 | * it's the caller responsability. |
| 718 | */ |
| 719 | void ust_registry_channel_destroy(struct ust_registry_channel *chan, bool notify) |
| 720 | { |
| 721 | struct lttng_ht_iter iter; |
| 722 | struct ust_registry_event *event; |
| 723 | enum lttng_error_code cmd_ret; |
| 724 | |
| 725 | LTTNG_ASSERT(chan); |
| 726 | |
| 727 | if (notify) { |
| 728 | cmd_ret = notification_thread_command_remove_channel( |
| 729 | the_notification_thread_handle, |
| 730 | chan->consumer_key, LTTNG_DOMAIN_UST); |
| 731 | if (cmd_ret != LTTNG_OK) { |
| 732 | ERR("Failed to remove channel from notification thread"); |
| 733 | } |
| 734 | } |
| 735 | |
| 736 | if (chan->events) { |
| 737 | rcu_read_lock(); |
| 738 | /* Destroy all event associated with this registry. */ |
| 739 | cds_lfht_for_each_entry( |
| 740 | chan->events->ht, &iter.iter, event, node.node) { |
| 741 | /* Delete the node from the ht and free it. */ |
| 742 | ust_registry_destroy_event(chan, event); |
| 743 | } |
| 744 | rcu_read_unlock(); |
| 745 | } |
| 746 | call_rcu(&chan->rcu_head, destroy_channel_rcu); |
| 747 | } |
| 748 | |
| 749 | /* |
| 750 | * Initialize registry with default values. |
| 751 | */ |
| 752 | int ust_registry_channel_add(ust_registry_session *session, |
| 753 | uint64_t key) |
| 754 | { |
| 755 | int ret = 0; |
| 756 | struct ust_registry_channel *chan; |
| 757 | |
| 758 | LTTNG_ASSERT(session); |
| 759 | |
| 760 | chan = zmalloc<ust_registry_channel>(); |
| 761 | if (!chan) { |
| 762 | PERROR("zmalloc ust registry channel"); |
| 763 | ret = -ENOMEM; |
| 764 | goto error_alloc; |
| 765 | } |
| 766 | |
| 767 | chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING); |
| 768 | if (!chan->events) { |
| 769 | ret = -ENOMEM; |
| 770 | goto error; |
| 771 | } |
| 772 | |
| 773 | /* Set custom match function. */ |
| 774 | chan->events->match_fct = ht_match_event; |
| 775 | chan->events->hash_fct = ht_hash_event; |
| 776 | |
| 777 | /* |
| 778 | * Assign a channel ID right now since the event notification comes |
| 779 | * *before* the channel notify so the ID needs to be set at this point so |
| 780 | * the metadata can be dumped for that event. |
| 781 | */ |
| 782 | if (ust_registry_is_max_id(session->_used_channel_id)) { |
| 783 | ret = -1; |
| 784 | goto error; |
| 785 | } |
| 786 | chan->chan_id = ust_registry_get_next_chan_id(session); |
| 787 | |
| 788 | rcu_read_lock(); |
| 789 | lttng_ht_node_init_u64(&chan->node, key); |
| 790 | lttng_ht_add_unique_u64(session->_channels.get(), &chan->node); |
| 791 | rcu_read_unlock(); |
| 792 | |
| 793 | return 0; |
| 794 | |
| 795 | error: |
| 796 | ust_registry_channel_destroy(chan, false); |
| 797 | error_alloc: |
| 798 | return ret; |
| 799 | } |
| 800 | |
| 801 | /* |
| 802 | * Find a channel in the given registry. RCU read side lock MUST be acquired |
| 803 | * before calling this function and as long as the event reference is kept by |
| 804 | * the caller. |
| 805 | * |
| 806 | * On success, the pointer is returned else NULL. |
| 807 | */ |
| 808 | struct ust_registry_channel *ust_registry_channel_find( |
| 809 | ust_registry_session *session, uint64_t key) |
| 810 | { |
| 811 | struct lttng_ht_node_u64 *node; |
| 812 | struct lttng_ht_iter iter; |
| 813 | struct ust_registry_channel *chan = NULL; |
| 814 | |
| 815 | LTTNG_ASSERT(session); |
| 816 | LTTNG_ASSERT(session->_channels); |
| 817 | ASSERT_RCU_READ_LOCKED(); |
| 818 | |
| 819 | DBG3("UST registry channel finding key %" PRIu64, key); |
| 820 | |
| 821 | lttng_ht_lookup(session->_channels.get(), &key, &iter); |
| 822 | node = lttng_ht_iter_get_node_u64(&iter); |
| 823 | if (!node) { |
| 824 | goto end; |
| 825 | } |
| 826 | chan = caa_container_of(node, struct ust_registry_channel, node); |
| 827 | |
| 828 | end: |
| 829 | return chan; |
| 830 | } |
| 831 | |
| 832 | /* |
| 833 | * Remove channel using key from registry and free memory. |
| 834 | */ |
| 835 | void ust_registry_channel_del_free(ust_registry_session *session, |
| 836 | uint64_t key, bool notif) |
| 837 | { |
| 838 | struct lttng_ht_iter iter; |
| 839 | struct ust_registry_channel *chan; |
| 840 | int ret; |
| 841 | |
| 842 | LTTNG_ASSERT(session); |
| 843 | |
| 844 | rcu_read_lock(); |
| 845 | chan = ust_registry_channel_find(session, key); |
| 846 | if (!chan) { |
| 847 | rcu_read_unlock(); |
| 848 | goto end; |
| 849 | } |
| 850 | |
| 851 | iter.iter.node = &chan->node.node; |
| 852 | ret = lttng_ht_del(session->_channels.get(), &iter); |
| 853 | LTTNG_ASSERT(!ret); |
| 854 | rcu_read_unlock(); |
| 855 | ust_registry_channel_destroy(chan, notif); |
| 856 | |
| 857 | end: |
| 858 | return; |
| 859 | } |
| 860 | |
| 861 | ust_registry_session *ust_registry_session_per_uid_create(uint32_t bits_per_long, |
| 862 | uint32_t uint8_t_alignment, |
| 863 | uint32_t uint16_t_alignment, |
| 864 | uint32_t uint32_t_alignment, |
| 865 | uint32_t uint64_t_alignment, |
| 866 | uint32_t long_alignment, |
| 867 | int byte_order, |
| 868 | uint32_t major, |
| 869 | uint32_t minor, |
| 870 | const char *root_shm_path, |
| 871 | const char *shm_path, |
| 872 | uid_t euid, |
| 873 | gid_t egid, |
| 874 | uint64_t tracing_id, |
| 875 | uid_t tracing_uid) |
| 876 | { |
| 877 | try { |
| 878 | return new ust_registry_session_per_uid(bits_per_long, uint8_t_alignment, |
| 879 | uint16_t_alignment, uint32_t_alignment, uint64_t_alignment, |
| 880 | long_alignment, byte_order, major, minor, root_shm_path, shm_path, |
| 881 | euid, egid, tracing_id, tracing_uid); |
| 882 | } catch (const std::exception &ex) { |
| 883 | ERR("Failed to create per-uid registry session: %s", ex.what()); |
| 884 | return nullptr; |
| 885 | } |
| 886 | } |
| 887 | |
| 888 | ust_registry_session *ust_registry_session_per_pid_create(struct ust_app *app, |
| 889 | uint32_t bits_per_long, |
| 890 | uint32_t uint8_t_alignment, |
| 891 | uint32_t uint16_t_alignment, |
| 892 | uint32_t uint32_t_alignment, |
| 893 | uint32_t uint64_t_alignment, |
| 894 | uint32_t long_alignment, |
| 895 | int byte_order, |
| 896 | uint32_t major, |
| 897 | uint32_t minor, |
| 898 | const char *root_shm_path, |
| 899 | const char *shm_path, |
| 900 | uid_t euid, |
| 901 | gid_t egid, |
| 902 | uint64_t tracing_id) |
| 903 | { |
| 904 | try { |
| 905 | return new ust_registry_session_per_pid(*app, bits_per_long, uint8_t_alignment, |
| 906 | uint16_t_alignment, uint32_t_alignment, uint64_t_alignment, |
| 907 | long_alignment, byte_order, major, minor, root_shm_path, shm_path, |
| 908 | euid, egid, tracing_id); |
| 909 | } catch (const std::exception &ex) { |
| 910 | ERR("Failed to create per-pid registry session: %s", ex.what()); |
| 911 | return nullptr; |
| 912 | } |
| 913 | } |
| 914 | |
| 915 | /* |
| 916 | * Destroy session registry. This does NOT free the given pointer since it |
| 917 | * might get passed as a reference. The registry lock should NOT be acquired. |
| 918 | */ |
| 919 | void ust_registry_session_destroy(ust_registry_session *reg) |
| 920 | { |
| 921 | delete reg; |
| 922 | } |