| 1 | /* |
| 2 | * ltt-events.c |
| 3 | * |
| 4 | * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | * |
| 6 | * Holds LTTng per-session event registry. |
| 7 | * |
| 8 | * Dual LGPL v2.1/GPL v2 license. |
| 9 | */ |
| 10 | |
| 11 | #define _GNU_SOURCE |
| 12 | #include <stdio.h> |
| 13 | #include <urcu/list.h> |
| 14 | #include <urcu/hlist.h> |
| 15 | #include <pthread.h> |
| 16 | #include <errno.h> |
| 17 | #include <sys/shm.h> |
| 18 | #include <sys/ipc.h> |
| 19 | #include <stdint.h> |
| 20 | #include <stddef.h> |
| 21 | #include <inttypes.h> |
| 22 | #include <time.h> |
| 23 | #include <lttng/ust-endian.h> |
| 24 | #include "clock.h" |
| 25 | |
| 26 | #include <urcu-bp.h> |
| 27 | #include <urcu/compiler.h> |
| 28 | #include <urcu/uatomic.h> |
| 29 | #include <urcu/arch.h> |
| 30 | |
| 31 | #include <lttng/tracepoint.h> |
| 32 | #include <lttng/ust-events.h> |
| 33 | |
| 34 | #include <usterr-signal-safe.h> |
| 35 | #include <helper.h> |
| 36 | #include "error.h" |
| 37 | #include "compat.h" |
| 38 | #include "lttng-ust-uuid.h" |
| 39 | |
| 40 | #include "tracepoint-internal.h" |
| 41 | #include "ltt-tracer.h" |
| 42 | #include "ltt-tracer-core.h" |
| 43 | #include "wait.h" |
| 44 | #include "../libringbuffer/shm.h" |
| 45 | #include "jhash.h" |
| 46 | |
| 47 | /* |
| 48 | * The sessions mutex is the centralized mutex across UST tracing |
| 49 | * control and probe registration. All operations within this file are |
| 50 | * called by the communication thread, under ust_lock protection. |
| 51 | */ |
| 52 | static pthread_mutex_t sessions_mutex = PTHREAD_MUTEX_INITIALIZER; |
| 53 | |
| 54 | void ust_lock(void) |
| 55 | { |
| 56 | pthread_mutex_lock(&sessions_mutex); |
| 57 | } |
| 58 | |
| 59 | void ust_unlock(void) |
| 60 | { |
| 61 | pthread_mutex_unlock(&sessions_mutex); |
| 62 | } |
| 63 | |
| 64 | static CDS_LIST_HEAD(sessions); |
| 65 | |
| 66 | /* |
| 67 | * Wildcard list, containing the active wildcards. |
| 68 | * Protected by ust lock. |
| 69 | */ |
| 70 | static CDS_LIST_HEAD(wildcard_list); |
| 71 | |
| 72 | /* |
| 73 | * Pending probes hash table, containing the registered ltt events for |
| 74 | * which tracepoint probes are still missing. Protected by the sessions |
| 75 | * mutex. |
| 76 | */ |
| 77 | #define PENDING_PROBE_HASH_BITS 6 |
| 78 | #define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS) |
| 79 | static struct cds_hlist_head pending_probe_table[PENDING_PROBE_HASH_SIZE]; |
| 80 | |
| 81 | struct ust_pending_probe { |
| 82 | struct ltt_event *event; |
| 83 | struct cds_hlist_node node; |
| 84 | enum lttng_ust_loglevel_type loglevel_type; |
| 85 | int loglevel; |
| 86 | char name[]; |
| 87 | }; |
| 88 | |
| 89 | static void _ltt_event_destroy(struct ltt_event *event); |
| 90 | static void _ltt_wildcard_destroy(struct session_wildcard *sw); |
| 91 | static void _ltt_channel_destroy(struct ltt_channel *chan); |
| 92 | static int _ltt_event_unregister(struct ltt_event *event); |
| 93 | static |
| 94 | int _ltt_event_metadata_statedump(struct ltt_session *session, |
| 95 | struct ltt_channel *chan, |
| 96 | struct ltt_event *event); |
| 97 | static |
| 98 | int _ltt_session_metadata_statedump(struct ltt_session *session); |
| 99 | |
| 100 | int ltt_loglevel_match(const struct lttng_event_desc *desc, |
| 101 | enum lttng_ust_loglevel_type req_type, |
| 102 | int req_loglevel) |
| 103 | { |
| 104 | int ev_loglevel; |
| 105 | |
| 106 | if (req_type == LTTNG_UST_LOGLEVEL_ALL) |
| 107 | return 1; |
| 108 | if (!desc->loglevel) |
| 109 | ev_loglevel = TRACE_DEFAULT; |
| 110 | else |
| 111 | ev_loglevel = *(*desc->loglevel); |
| 112 | switch (req_type) { |
| 113 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 114 | if (ev_loglevel <= req_loglevel || req_loglevel == -1) |
| 115 | return 1; |
| 116 | else |
| 117 | return 0; |
| 118 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 119 | if (ev_loglevel == req_loglevel || req_loglevel == -1) |
| 120 | return 1; |
| 121 | else |
| 122 | return 0; |
| 123 | case LTTNG_UST_LOGLEVEL_ALL: |
| 124 | default: |
| 125 | return 1; |
| 126 | } |
| 127 | } |
| 128 | |
| 129 | /* |
| 130 | * Return wildcard for a given event name if the event name match the |
| 131 | * one of the wildcards. |
| 132 | * Must be called with ust lock held. |
| 133 | * Returns NULL if not present. |
| 134 | */ |
| 135 | static |
| 136 | struct wildcard_entry *match_wildcard(const struct lttng_event_desc *desc) |
| 137 | { |
| 138 | struct wildcard_entry *e; |
| 139 | |
| 140 | cds_list_for_each_entry(e, &wildcard_list, list) { |
| 141 | /* If only contain '*' */ |
| 142 | if (strlen(e->name) == 1) |
| 143 | goto possible_match; |
| 144 | /* Compare excluding final '*' */ |
| 145 | if (!strncmp(desc->name, e->name, strlen(e->name) - 1)) |
| 146 | goto possible_match; |
| 147 | continue; /* goto next, no match */ |
| 148 | possible_match: |
| 149 | if (ltt_loglevel_match(desc, |
| 150 | e->loglevel_type, |
| 151 | e->loglevel)) { |
| 152 | return e; |
| 153 | } |
| 154 | /* no match, loop to next */ |
| 155 | } |
| 156 | return NULL; |
| 157 | } |
| 158 | |
| 159 | /* |
| 160 | * called at event creation if probe is missing. |
| 161 | * called with session mutex held. |
| 162 | */ |
| 163 | static |
| 164 | int add_pending_probe(struct ltt_event *event, const char *name, |
| 165 | enum lttng_ust_loglevel_type loglevel_type, |
| 166 | int loglevel) |
| 167 | { |
| 168 | struct cds_hlist_head *head; |
| 169 | struct ust_pending_probe *e; |
| 170 | size_t name_len = strlen(name); |
| 171 | uint32_t hash; |
| 172 | |
| 173 | if (name_len > LTTNG_UST_SYM_NAME_LEN - 1) { |
| 174 | WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN - 1); |
| 175 | name_len = LTTNG_UST_SYM_NAME_LEN - 1; |
| 176 | } |
| 177 | hash = jhash(name, name_len, 0); |
| 178 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; |
| 179 | e = zmalloc(sizeof(struct ust_pending_probe) + name_len); |
| 180 | if (!e) |
| 181 | return -ENOMEM; |
| 182 | memcpy(&e->name[0], name, name_len + 1); |
| 183 | e->name[name_len] = '\0'; |
| 184 | e->loglevel_type = loglevel_type; |
| 185 | e->loglevel = loglevel; |
| 186 | cds_hlist_add_head(&e->node, head); |
| 187 | e->event = event; |
| 188 | event->pending_probe = e; |
| 189 | return 0; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * remove a pending probe. called when at event teardown and when an |
| 194 | * event is fixed (probe is loaded). |
| 195 | * called with session mutex held. |
| 196 | */ |
| 197 | static |
| 198 | void remove_pending_probe(struct ust_pending_probe *e) |
| 199 | { |
| 200 | if (!e) |
| 201 | return; |
| 202 | cds_hlist_del(&e->node); |
| 203 | free(e); |
| 204 | } |
| 205 | |
| 206 | /* |
| 207 | * Called at library load: connect the probe on the events pending on |
| 208 | * probe load. |
| 209 | * called with session mutex held. |
| 210 | */ |
| 211 | int pending_probe_fix_events(const struct lttng_event_desc *desc) |
| 212 | { |
| 213 | struct cds_hlist_head *head; |
| 214 | struct cds_hlist_node *node, *p; |
| 215 | struct ust_pending_probe *e; |
| 216 | const char *name = desc->name; |
| 217 | int ret = 0; |
| 218 | struct lttng_ust_event event_param; |
| 219 | size_t name_len = strlen(name); |
| 220 | uint32_t hash; |
| 221 | |
| 222 | /* Wildcard */ |
| 223 | { |
| 224 | struct wildcard_entry *wildcard; |
| 225 | |
| 226 | wildcard = match_wildcard(desc); |
| 227 | if (strcmp(desc->name, "lttng_ust:metadata") && wildcard) { |
| 228 | struct session_wildcard *sw; |
| 229 | |
| 230 | cds_list_for_each_entry(sw, &wildcard->session_list, |
| 231 | session_list) { |
| 232 | struct ltt_event *ev; |
| 233 | int ret; |
| 234 | |
| 235 | memcpy(&event_param, &sw->event_param, |
| 236 | sizeof(event_param)); |
| 237 | memcpy(event_param.name, |
| 238 | desc->name, |
| 239 | sizeof(event_param.name)); |
| 240 | /* create event */ |
| 241 | ret = ltt_event_create(sw->chan, |
| 242 | &event_param, NULL, |
| 243 | &ev); |
| 244 | if (ret) { |
| 245 | DBG("Error creating event"); |
| 246 | continue; |
| 247 | } |
| 248 | cds_list_add(&ev->wildcard_list, |
| 249 | &sw->events); |
| 250 | } |
| 251 | } |
| 252 | } |
| 253 | |
| 254 | if (name_len > LTTNG_UST_SYM_NAME_LEN - 1) { |
| 255 | WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN - 1); |
| 256 | name_len = LTTNG_UST_SYM_NAME_LEN - 1; |
| 257 | } |
| 258 | hash = jhash(name, name_len, 0); |
| 259 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; |
| 260 | cds_hlist_for_each_entry_safe(e, node, p, head, node) { |
| 261 | struct ltt_event *event; |
| 262 | struct ltt_channel *chan; |
| 263 | |
| 264 | if (!ltt_loglevel_match(desc, |
| 265 | e->loglevel_type, |
| 266 | e->loglevel)) { |
| 267 | continue; |
| 268 | } |
| 269 | if (strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1)) { |
| 270 | continue; |
| 271 | } |
| 272 | event = e->event; |
| 273 | chan = event->chan; |
| 274 | assert(!event->desc); |
| 275 | event->desc = desc; |
| 276 | event->pending_probe = NULL; |
| 277 | remove_pending_probe(e); |
| 278 | ret |= __tracepoint_probe_register(name, |
| 279 | event->desc->probe_callback, |
| 280 | event); |
| 281 | if (ret) |
| 282 | continue; |
| 283 | event->id = chan->free_event_id++; |
| 284 | ret |= _ltt_event_metadata_statedump(chan->session, chan, |
| 285 | event); |
| 286 | } |
| 287 | return ret; |
| 288 | } |
| 289 | |
| 290 | void synchronize_trace(void) |
| 291 | { |
| 292 | synchronize_rcu(); |
| 293 | } |
| 294 | |
| 295 | struct ltt_session *ltt_session_create(void) |
| 296 | { |
| 297 | struct ltt_session *session; |
| 298 | int ret; |
| 299 | |
| 300 | session = zmalloc(sizeof(struct ltt_session)); |
| 301 | if (!session) |
| 302 | return NULL; |
| 303 | CDS_INIT_LIST_HEAD(&session->chan); |
| 304 | CDS_INIT_LIST_HEAD(&session->events); |
| 305 | CDS_INIT_LIST_HEAD(&session->wildcards); |
| 306 | ret = lttng_ust_uuid_generate(session->uuid); |
| 307 | if (ret != 0) { |
| 308 | session->uuid[0] = '\0'; |
| 309 | } |
| 310 | cds_list_add(&session->list, &sessions); |
| 311 | return session; |
| 312 | } |
| 313 | |
| 314 | void ltt_session_destroy(struct ltt_session *session) |
| 315 | { |
| 316 | struct ltt_channel *chan, *tmpchan; |
| 317 | struct ltt_event *event, *tmpevent; |
| 318 | struct session_wildcard *wildcard, *tmpwildcard; |
| 319 | int ret; |
| 320 | |
| 321 | CMM_ACCESS_ONCE(session->active) = 0; |
| 322 | cds_list_for_each_entry(event, &session->events, list) { |
| 323 | ret = _ltt_event_unregister(event); |
| 324 | WARN_ON(ret); |
| 325 | } |
| 326 | synchronize_trace(); /* Wait for in-flight events to complete */ |
| 327 | cds_list_for_each_entry_safe(wildcard, tmpwildcard, &session->wildcards, list) |
| 328 | _ltt_wildcard_destroy(wildcard); |
| 329 | cds_list_for_each_entry_safe(event, tmpevent, &session->events, list) |
| 330 | _ltt_event_destroy(event); |
| 331 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list) |
| 332 | _ltt_channel_destroy(chan); |
| 333 | cds_list_del(&session->list); |
| 334 | free(session); |
| 335 | } |
| 336 | |
| 337 | int ltt_session_enable(struct ltt_session *session) |
| 338 | { |
| 339 | int ret = 0; |
| 340 | struct ltt_channel *chan; |
| 341 | |
| 342 | if (session->active) { |
| 343 | ret = -EBUSY; |
| 344 | goto end; |
| 345 | } |
| 346 | |
| 347 | /* |
| 348 | * Snapshot the number of events per channel to know the type of header |
| 349 | * we need to use. |
| 350 | */ |
| 351 | cds_list_for_each_entry(chan, &session->chan, list) { |
| 352 | if (chan->header_type) |
| 353 | continue; /* don't change it if session stop/restart */ |
| 354 | if (chan->free_event_id < 31) |
| 355 | chan->header_type = 1; /* compact */ |
| 356 | else |
| 357 | chan->header_type = 2; /* large */ |
| 358 | } |
| 359 | |
| 360 | CMM_ACCESS_ONCE(session->active) = 1; |
| 361 | CMM_ACCESS_ONCE(session->been_active) = 1; |
| 362 | ret = _ltt_session_metadata_statedump(session); |
| 363 | if (ret) |
| 364 | CMM_ACCESS_ONCE(session->active) = 0; |
| 365 | end: |
| 366 | return ret; |
| 367 | } |
| 368 | |
| 369 | int ltt_session_disable(struct ltt_session *session) |
| 370 | { |
| 371 | int ret = 0; |
| 372 | |
| 373 | if (!session->active) { |
| 374 | ret = -EBUSY; |
| 375 | goto end; |
| 376 | } |
| 377 | CMM_ACCESS_ONCE(session->active) = 0; |
| 378 | end: |
| 379 | return ret; |
| 380 | } |
| 381 | |
| 382 | int ltt_channel_enable(struct ltt_channel *channel) |
| 383 | { |
| 384 | int old; |
| 385 | |
| 386 | if (channel == channel->session->metadata) |
| 387 | return -EPERM; |
| 388 | old = uatomic_xchg(&channel->enabled, 1); |
| 389 | if (old) |
| 390 | return -EEXIST; |
| 391 | return 0; |
| 392 | } |
| 393 | |
| 394 | int ltt_channel_disable(struct ltt_channel *channel) |
| 395 | { |
| 396 | int old; |
| 397 | |
| 398 | if (channel == channel->session->metadata) |
| 399 | return -EPERM; |
| 400 | old = uatomic_xchg(&channel->enabled, 0); |
| 401 | if (!old) |
| 402 | return -EEXIST; |
| 403 | return 0; |
| 404 | } |
| 405 | |
| 406 | int ltt_event_enable(struct ltt_event *event) |
| 407 | { |
| 408 | int old; |
| 409 | |
| 410 | if (event->chan == event->chan->session->metadata) |
| 411 | return -EPERM; |
| 412 | old = uatomic_xchg(&event->enabled, 1); |
| 413 | if (old) |
| 414 | return -EEXIST; |
| 415 | return 0; |
| 416 | } |
| 417 | |
| 418 | int ltt_event_disable(struct ltt_event *event) |
| 419 | { |
| 420 | int old; |
| 421 | |
| 422 | if (event->chan == event->chan->session->metadata) |
| 423 | return -EPERM; |
| 424 | old = uatomic_xchg(&event->enabled, 0); |
| 425 | if (!old) |
| 426 | return -EEXIST; |
| 427 | return 0; |
| 428 | } |
| 429 | |
| 430 | struct ltt_channel *ltt_channel_create(struct ltt_session *session, |
| 431 | const char *transport_name, |
| 432 | void *buf_addr, |
| 433 | size_t subbuf_size, size_t num_subbuf, |
| 434 | unsigned int switch_timer_interval, |
| 435 | unsigned int read_timer_interval, |
| 436 | int **shm_fd, int **wait_fd, |
| 437 | uint64_t **memory_map_size, |
| 438 | struct ltt_channel *chan_priv_init) |
| 439 | { |
| 440 | struct ltt_channel *chan = NULL; |
| 441 | struct ltt_transport *transport; |
| 442 | |
| 443 | if (session->been_active) |
| 444 | goto active; /* Refuse to add channel to active session */ |
| 445 | transport = ltt_transport_find(transport_name); |
| 446 | if (!transport) { |
| 447 | DBG("LTTng transport %s not found\n", |
| 448 | transport_name); |
| 449 | goto notransport; |
| 450 | } |
| 451 | chan_priv_init->id = session->free_chan_id++; |
| 452 | chan_priv_init->session = session; |
| 453 | /* |
| 454 | * Note: the channel creation op already writes into the packet |
| 455 | * headers. Therefore the "chan" information used as input |
| 456 | * should be already accessible. |
| 457 | */ |
| 458 | chan = transport->ops.channel_create("[lttng]", buf_addr, |
| 459 | subbuf_size, num_subbuf, switch_timer_interval, |
| 460 | read_timer_interval, shm_fd, wait_fd, |
| 461 | memory_map_size, chan_priv_init); |
| 462 | if (!chan) |
| 463 | goto create_error; |
| 464 | chan->enabled = 1; |
| 465 | chan->ops = &transport->ops; |
| 466 | cds_list_add(&chan->list, &session->chan); |
| 467 | return chan; |
| 468 | |
| 469 | create_error: |
| 470 | notransport: |
| 471 | active: |
| 472 | return NULL; |
| 473 | } |
| 474 | |
| 475 | /* |
| 476 | * Only used internally at session destruction. |
| 477 | */ |
| 478 | static |
| 479 | void _ltt_channel_destroy(struct ltt_channel *chan) |
| 480 | { |
| 481 | cds_list_del(&chan->list); |
| 482 | lttng_destroy_context(chan->ctx); |
| 483 | chan->ops->channel_destroy(chan); |
| 484 | } |
| 485 | |
| 486 | /* |
| 487 | * Supports event creation while tracing session is active. |
| 488 | */ |
| 489 | int ltt_event_create(struct ltt_channel *chan, |
| 490 | struct lttng_ust_event *event_param, |
| 491 | void *filter, |
| 492 | struct ltt_event **_event) |
| 493 | { |
| 494 | const struct lttng_event_desc *desc = NULL; /* silence gcc */ |
| 495 | struct ltt_event *event; |
| 496 | int ret = 0; |
| 497 | |
| 498 | if (chan->used_event_id == -1UL) { |
| 499 | ret = -ENOMEM; |
| 500 | goto full; |
| 501 | } |
| 502 | /* |
| 503 | * This is O(n^2) (for each event, the loop is called at event |
| 504 | * creation). Might require a hash if we have lots of events. |
| 505 | */ |
| 506 | cds_list_for_each_entry(event, &chan->session->events, list) { |
| 507 | if (event->desc && !strncmp(event->desc->name, |
| 508 | event_param->name, |
| 509 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
| 510 | ret = -EEXIST; |
| 511 | goto exist; |
| 512 | } |
| 513 | } |
| 514 | |
| 515 | /* |
| 516 | * Check if loglevel match. Refuse to connect event if not. |
| 517 | */ |
| 518 | if (event_param->instrumentation == LTTNG_UST_TRACEPOINT) { |
| 519 | desc = ltt_event_get(event_param->name); |
| 520 | if (desc) { |
| 521 | if (!ltt_loglevel_match(desc, |
| 522 | event_param->loglevel_type, |
| 523 | event_param->loglevel)) { |
| 524 | ret = -EPERM; |
| 525 | goto no_loglevel_match; |
| 526 | } |
| 527 | } |
| 528 | /* |
| 529 | * If descriptor is not there, it will be added to |
| 530 | * pending probes. |
| 531 | */ |
| 532 | } |
| 533 | event = zmalloc(sizeof(struct ltt_event)); |
| 534 | if (!event) { |
| 535 | ret = -ENOMEM; |
| 536 | goto cache_error; |
| 537 | } |
| 538 | event->chan = chan; |
| 539 | event->filter = filter; |
| 540 | /* |
| 541 | * used_event_id counts the maximum number of event IDs that can |
| 542 | * register if all probes register. |
| 543 | */ |
| 544 | chan->used_event_id++; |
| 545 | event->enabled = 1; |
| 546 | event->instrumentation = event_param->instrumentation; |
| 547 | /* Populate ltt_event structure before tracepoint registration. */ |
| 548 | cmm_smp_wmb(); |
| 549 | switch (event_param->instrumentation) { |
| 550 | case LTTNG_UST_TRACEPOINT: |
| 551 | event->desc = desc; |
| 552 | if (event->desc) { |
| 553 | ret = __tracepoint_probe_register(event_param->name, |
| 554 | event->desc->probe_callback, |
| 555 | event); |
| 556 | if (ret) |
| 557 | goto register_error; |
| 558 | event->id = chan->free_event_id++; |
| 559 | } else { |
| 560 | /* |
| 561 | * If the probe is not present, event->desc stays NULL, |
| 562 | * waiting for the probe to register, and the event->id |
| 563 | * stays unallocated. |
| 564 | */ |
| 565 | ret = add_pending_probe(event, event_param->name, |
| 566 | event_param->loglevel_type, |
| 567 | event_param->loglevel); |
| 568 | if (ret) |
| 569 | goto add_pending_error; |
| 570 | } |
| 571 | break; |
| 572 | default: |
| 573 | WARN_ON_ONCE(1); |
| 574 | } |
| 575 | if (event->desc) { |
| 576 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); |
| 577 | if (ret) |
| 578 | goto statedump_error; |
| 579 | } |
| 580 | cds_list_add(&event->list, &chan->session->events); |
| 581 | *_event = event; |
| 582 | return 0; |
| 583 | |
| 584 | statedump_error: |
| 585 | if (event->desc) { |
| 586 | WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name, |
| 587 | event->desc->probe_callback, |
| 588 | event)); |
| 589 | ltt_event_put(event->desc); |
| 590 | } |
| 591 | add_pending_error: |
| 592 | register_error: |
| 593 | free(event); |
| 594 | cache_error: |
| 595 | no_loglevel_match: |
| 596 | exist: |
| 597 | full: |
| 598 | return ret; |
| 599 | } |
| 600 | |
| 601 | /* |
| 602 | * Only used internally at session destruction. |
| 603 | */ |
| 604 | int _ltt_event_unregister(struct ltt_event *event) |
| 605 | { |
| 606 | int ret = -EINVAL; |
| 607 | |
| 608 | switch (event->instrumentation) { |
| 609 | case LTTNG_UST_TRACEPOINT: |
| 610 | if (event->desc) { |
| 611 | ret = __tracepoint_probe_unregister(event->desc->name, |
| 612 | event->desc->probe_callback, |
| 613 | event); |
| 614 | if (ret) |
| 615 | return ret; |
| 616 | } else { |
| 617 | remove_pending_probe(event->pending_probe); |
| 618 | ret = 0; |
| 619 | } |
| 620 | break; |
| 621 | default: |
| 622 | WARN_ON_ONCE(1); |
| 623 | } |
| 624 | return ret; |
| 625 | } |
| 626 | |
| 627 | /* |
| 628 | * Only used internally at session destruction. |
| 629 | */ |
| 630 | static |
| 631 | void _ltt_event_destroy(struct ltt_event *event) |
| 632 | { |
| 633 | switch (event->instrumentation) { |
| 634 | case LTTNG_UST_TRACEPOINT: |
| 635 | if (event->desc) { |
| 636 | ltt_event_put(event->desc); |
| 637 | } |
| 638 | break; |
| 639 | default: |
| 640 | WARN_ON_ONCE(1); |
| 641 | } |
| 642 | cds_list_del(&event->list); |
| 643 | lttng_destroy_context(event->ctx); |
| 644 | free(event); |
| 645 | } |
| 646 | |
| 647 | /* |
| 648 | * We have exclusive access to our metadata buffer (protected by the |
| 649 | * ust_lock), so we can do racy operations such as looking for |
| 650 | * remaining space left in packet and write, since mutual exclusion |
| 651 | * protects us from concurrent writes. |
| 652 | */ |
| 653 | int lttng_metadata_printf(struct ltt_session *session, |
| 654 | const char *fmt, ...) |
| 655 | { |
| 656 | struct lttng_ust_lib_ring_buffer_ctx ctx; |
| 657 | struct ltt_channel *chan = session->metadata; |
| 658 | char *str = NULL; |
| 659 | int ret = 0, waitret; |
| 660 | size_t len, reserve_len, pos; |
| 661 | va_list ap; |
| 662 | |
| 663 | WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active)); |
| 664 | |
| 665 | va_start(ap, fmt); |
| 666 | ret = vasprintf(&str, fmt, ap); |
| 667 | va_end(ap); |
| 668 | if (ret < 0) |
| 669 | return -ENOMEM; |
| 670 | |
| 671 | len = strlen(str); |
| 672 | pos = 0; |
| 673 | |
| 674 | for (pos = 0; pos < len; pos += reserve_len) { |
| 675 | reserve_len = min_t(size_t, |
| 676 | chan->ops->packet_avail_size(chan->chan, chan->handle), |
| 677 | len - pos); |
| 678 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, |
| 679 | sizeof(char), -1, chan->handle); |
| 680 | /* |
| 681 | * We don't care about metadata buffer's records lost |
| 682 | * count, because we always retry here. Report error if |
| 683 | * we need to bail out after timeout or being |
| 684 | * interrupted. |
| 685 | */ |
| 686 | waitret = wait_cond_interruptible_timeout( |
| 687 | ({ |
| 688 | ret = chan->ops->event_reserve(&ctx, 0); |
| 689 | ret != -ENOBUFS || !ret; |
| 690 | }), |
| 691 | LTTNG_METADATA_TIMEOUT_MSEC); |
| 692 | if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) { |
| 693 | DBG("LTTng: Failure to write metadata to buffers (%s)\n", |
| 694 | waitret == -EINTR ? "interrupted" : |
| 695 | (ret == -ENOBUFS ? "timeout" : "I/O error")); |
| 696 | if (waitret == -EINTR) |
| 697 | ret = waitret; |
| 698 | goto end; |
| 699 | } |
| 700 | chan->ops->event_write(&ctx, &str[pos], reserve_len); |
| 701 | chan->ops->event_commit(&ctx); |
| 702 | } |
| 703 | end: |
| 704 | free(str); |
| 705 | return ret; |
| 706 | } |
| 707 | |
| 708 | static |
| 709 | int _ltt_field_statedump(struct ltt_session *session, |
| 710 | const struct lttng_event_field *field) |
| 711 | { |
| 712 | int ret = 0; |
| 713 | |
| 714 | switch (field->type.atype) { |
| 715 | case atype_integer: |
| 716 | ret = lttng_metadata_printf(session, |
| 717 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
| 718 | field->type.u.basic.integer.size, |
| 719 | field->type.u.basic.integer.alignment, |
| 720 | field->type.u.basic.integer.signedness, |
| 721 | (field->type.u.basic.integer.encoding == lttng_encode_none) |
| 722 | ? "none" |
| 723 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) |
| 724 | ? "UTF8" |
| 725 | : "ASCII", |
| 726 | field->type.u.basic.integer.base, |
| 727 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 728 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 729 | #else |
| 730 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 731 | #endif |
| 732 | field->name); |
| 733 | break; |
| 734 | case atype_float: |
| 735 | ret = lttng_metadata_printf(session, |
| 736 | " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n", |
| 737 | field->type.u.basic._float.exp_dig, |
| 738 | field->type.u.basic._float.mant_dig, |
| 739 | field->type.u.basic._float.alignment, |
| 740 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 741 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 742 | #else |
| 743 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 744 | #endif |
| 745 | field->name); |
| 746 | break; |
| 747 | case atype_enum: |
| 748 | ret = lttng_metadata_printf(session, |
| 749 | " %s %s;\n", |
| 750 | field->type.u.basic.enumeration.name, |
| 751 | field->name); |
| 752 | break; |
| 753 | case atype_array: |
| 754 | { |
| 755 | const struct lttng_basic_type *elem_type; |
| 756 | |
| 757 | elem_type = &field->type.u.array.elem_type; |
| 758 | ret = lttng_metadata_printf(session, |
| 759 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
| 760 | elem_type->u.basic.integer.size, |
| 761 | elem_type->u.basic.integer.alignment, |
| 762 | elem_type->u.basic.integer.signedness, |
| 763 | (elem_type->u.basic.integer.encoding == lttng_encode_none) |
| 764 | ? "none" |
| 765 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 766 | ? "UTF8" |
| 767 | : "ASCII", |
| 768 | elem_type->u.basic.integer.base, |
| 769 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 770 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 771 | #else |
| 772 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 773 | #endif |
| 774 | field->name, field->type.u.array.length); |
| 775 | break; |
| 776 | } |
| 777 | case atype_sequence: |
| 778 | { |
| 779 | const struct lttng_basic_type *elem_type; |
| 780 | const struct lttng_basic_type *length_type; |
| 781 | |
| 782 | elem_type = &field->type.u.sequence.elem_type; |
| 783 | length_type = &field->type.u.sequence.length_type; |
| 784 | ret = lttng_metadata_printf(session, |
| 785 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", |
| 786 | length_type->u.basic.integer.size, |
| 787 | (unsigned int) length_type->u.basic.integer.alignment, |
| 788 | length_type->u.basic.integer.signedness, |
| 789 | (length_type->u.basic.integer.encoding == lttng_encode_none) |
| 790 | ? "none" |
| 791 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 792 | ? "UTF8" |
| 793 | : "ASCII"), |
| 794 | length_type->u.basic.integer.base, |
| 795 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 796 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 797 | #else |
| 798 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 799 | #endif |
| 800 | field->name); |
| 801 | if (ret) |
| 802 | return ret; |
| 803 | |
| 804 | ret = lttng_metadata_printf(session, |
| 805 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
| 806 | elem_type->u.basic.integer.size, |
| 807 | (unsigned int) elem_type->u.basic.integer.alignment, |
| 808 | elem_type->u.basic.integer.signedness, |
| 809 | (elem_type->u.basic.integer.encoding == lttng_encode_none) |
| 810 | ? "none" |
| 811 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 812 | ? "UTF8" |
| 813 | : "ASCII"), |
| 814 | elem_type->u.basic.integer.base, |
| 815 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 816 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 817 | #else |
| 818 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 819 | #endif |
| 820 | field->name, |
| 821 | field->name); |
| 822 | break; |
| 823 | } |
| 824 | |
| 825 | case atype_string: |
| 826 | /* Default encoding is UTF8 */ |
| 827 | ret = lttng_metadata_printf(session, |
| 828 | " string%s _%s;\n", |
| 829 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
| 830 | " { encoding = ASCII; }" : "", |
| 831 | field->name); |
| 832 | break; |
| 833 | default: |
| 834 | WARN_ON_ONCE(1); |
| 835 | return -EINVAL; |
| 836 | } |
| 837 | return ret; |
| 838 | } |
| 839 | |
| 840 | static |
| 841 | int _ltt_context_metadata_statedump(struct ltt_session *session, |
| 842 | struct lttng_ctx *ctx) |
| 843 | { |
| 844 | int ret = 0; |
| 845 | int i; |
| 846 | |
| 847 | if (!ctx) |
| 848 | return 0; |
| 849 | for (i = 0; i < ctx->nr_fields; i++) { |
| 850 | const struct lttng_ctx_field *field = &ctx->fields[i]; |
| 851 | |
| 852 | ret = _ltt_field_statedump(session, &field->event_field); |
| 853 | if (ret) |
| 854 | return ret; |
| 855 | } |
| 856 | return ret; |
| 857 | } |
| 858 | |
| 859 | static |
| 860 | int _ltt_fields_metadata_statedump(struct ltt_session *session, |
| 861 | struct ltt_event *event) |
| 862 | { |
| 863 | const struct lttng_event_desc *desc = event->desc; |
| 864 | int ret = 0; |
| 865 | int i; |
| 866 | |
| 867 | for (i = 0; i < desc->nr_fields; i++) { |
| 868 | const struct lttng_event_field *field = &desc->fields[i]; |
| 869 | |
| 870 | ret = _ltt_field_statedump(session, field); |
| 871 | if (ret) |
| 872 | return ret; |
| 873 | } |
| 874 | return ret; |
| 875 | } |
| 876 | |
| 877 | static |
| 878 | int _ltt_event_metadata_statedump(struct ltt_session *session, |
| 879 | struct ltt_channel *chan, |
| 880 | struct ltt_event *event) |
| 881 | { |
| 882 | int ret = 0; |
| 883 | int loglevel = TRACE_DEFAULT; |
| 884 | |
| 885 | if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
| 886 | return 0; |
| 887 | if (chan == session->metadata) |
| 888 | return 0; |
| 889 | /* |
| 890 | * Don't print events for which probe load is pending. |
| 891 | */ |
| 892 | if (!event->desc) |
| 893 | return 0; |
| 894 | |
| 895 | ret = lttng_metadata_printf(session, |
| 896 | "event {\n" |
| 897 | " name = \"%s\";\n" |
| 898 | " id = %u;\n" |
| 899 | " stream_id = %u;\n", |
| 900 | event->desc->name, |
| 901 | event->id, |
| 902 | event->chan->id); |
| 903 | if (ret) |
| 904 | goto end; |
| 905 | |
| 906 | if (event->desc->loglevel) |
| 907 | loglevel = *(*event->desc->loglevel); |
| 908 | |
| 909 | ret = lttng_metadata_printf(session, |
| 910 | " loglevel = %d;\n", |
| 911 | loglevel); |
| 912 | if (ret) |
| 913 | goto end; |
| 914 | |
| 915 | if (event->ctx) { |
| 916 | ret = lttng_metadata_printf(session, |
| 917 | " context := struct {\n"); |
| 918 | if (ret) |
| 919 | goto end; |
| 920 | } |
| 921 | ret = _ltt_context_metadata_statedump(session, event->ctx); |
| 922 | if (ret) |
| 923 | goto end; |
| 924 | if (event->ctx) { |
| 925 | ret = lttng_metadata_printf(session, |
| 926 | " };\n"); |
| 927 | if (ret) |
| 928 | goto end; |
| 929 | } |
| 930 | |
| 931 | ret = lttng_metadata_printf(session, |
| 932 | " fields := struct {\n" |
| 933 | ); |
| 934 | if (ret) |
| 935 | goto end; |
| 936 | |
| 937 | ret = _ltt_fields_metadata_statedump(session, event); |
| 938 | if (ret) |
| 939 | goto end; |
| 940 | |
| 941 | /* |
| 942 | * LTTng space reservation can only reserve multiples of the |
| 943 | * byte size. |
| 944 | */ |
| 945 | ret = lttng_metadata_printf(session, |
| 946 | " };\n" |
| 947 | "};\n\n"); |
| 948 | if (ret) |
| 949 | goto end; |
| 950 | |
| 951 | event->metadata_dumped = 1; |
| 952 | end: |
| 953 | return ret; |
| 954 | |
| 955 | } |
| 956 | |
| 957 | static |
| 958 | int _ltt_channel_metadata_statedump(struct ltt_session *session, |
| 959 | struct ltt_channel *chan) |
| 960 | { |
| 961 | int ret = 0; |
| 962 | |
| 963 | if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
| 964 | return 0; |
| 965 | if (chan == session->metadata) |
| 966 | return 0; |
| 967 | |
| 968 | WARN_ON_ONCE(!chan->header_type); |
| 969 | ret = lttng_metadata_printf(session, |
| 970 | "stream {\n" |
| 971 | " id = %u;\n" |
| 972 | " event.header := %s;\n" |
| 973 | " packet.context := struct packet_context;\n", |
| 974 | chan->id, |
| 975 | chan->header_type == 1 ? "struct event_header_compact" : |
| 976 | "struct event_header_large"); |
| 977 | if (ret) |
| 978 | goto end; |
| 979 | |
| 980 | if (chan->ctx) { |
| 981 | ret = lttng_metadata_printf(session, |
| 982 | " event.context := struct {\n"); |
| 983 | if (ret) |
| 984 | goto end; |
| 985 | } |
| 986 | ret = _ltt_context_metadata_statedump(session, chan->ctx); |
| 987 | if (ret) |
| 988 | goto end; |
| 989 | if (chan->ctx) { |
| 990 | ret = lttng_metadata_printf(session, |
| 991 | " };\n"); |
| 992 | if (ret) |
| 993 | goto end; |
| 994 | } |
| 995 | |
| 996 | ret = lttng_metadata_printf(session, |
| 997 | "};\n\n"); |
| 998 | |
| 999 | chan->metadata_dumped = 1; |
| 1000 | end: |
| 1001 | return ret; |
| 1002 | } |
| 1003 | |
| 1004 | static |
| 1005 | int _ltt_stream_packet_context_declare(struct ltt_session *session) |
| 1006 | { |
| 1007 | return lttng_metadata_printf(session, |
| 1008 | "struct packet_context {\n" |
| 1009 | " uint64_clock_monotonic_t timestamp_begin;\n" |
| 1010 | " uint64_clock_monotonic_t timestamp_end;\n" |
| 1011 | " uint32_t events_discarded;\n" |
| 1012 | " uint32_t content_size;\n" |
| 1013 | " uint32_t packet_size;\n" |
| 1014 | " uint32_t cpu_id;\n" |
| 1015 | "};\n\n" |
| 1016 | ); |
| 1017 | } |
| 1018 | |
| 1019 | /* |
| 1020 | * Compact header: |
| 1021 | * id: range: 0 - 30. |
| 1022 | * id 31 is reserved to indicate an extended header. |
| 1023 | * |
| 1024 | * Large header: |
| 1025 | * id: range: 0 - 65534. |
| 1026 | * id 65535 is reserved to indicate an extended header. |
| 1027 | */ |
| 1028 | static |
| 1029 | int _ltt_event_header_declare(struct ltt_session *session) |
| 1030 | { |
| 1031 | return lttng_metadata_printf(session, |
| 1032 | "struct event_header_compact {\n" |
| 1033 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" |
| 1034 | " variant <id> {\n" |
| 1035 | " struct {\n" |
| 1036 | " uint27_clock_monotonic_t timestamp;\n" |
| 1037 | " } compact;\n" |
| 1038 | " struct {\n" |
| 1039 | " uint32_t id;\n" |
| 1040 | " uint64_clock_monotonic_t timestamp;\n" |
| 1041 | " } extended;\n" |
| 1042 | " } v;\n" |
| 1043 | "} align(%u);\n" |
| 1044 | "\n" |
| 1045 | "struct event_header_large {\n" |
| 1046 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" |
| 1047 | " variant <id> {\n" |
| 1048 | " struct {\n" |
| 1049 | " uint32_clock_monotonic_t timestamp;\n" |
| 1050 | " } compact;\n" |
| 1051 | " struct {\n" |
| 1052 | " uint32_t id;\n" |
| 1053 | " uint64_clock_monotonic_t timestamp;\n" |
| 1054 | " } extended;\n" |
| 1055 | " } v;\n" |
| 1056 | "} align(%u);\n\n", |
| 1057 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 1058 | lttng_alignof(uint16_t) * CHAR_BIT |
| 1059 | ); |
| 1060 | } |
| 1061 | |
| 1062 | /* |
| 1063 | * Approximation of NTP time of day to clock monotonic correlation, |
| 1064 | * taken at start of trace. |
| 1065 | * Yes, this is only an approximation. Yes, we can (and will) do better |
| 1066 | * in future versions. |
| 1067 | */ |
| 1068 | static |
| 1069 | uint64_t measure_clock_offset(void) |
| 1070 | { |
| 1071 | uint64_t offset, monotonic[2], realtime; |
| 1072 | struct timespec rts = { 0, 0 }; |
| 1073 | int ret; |
| 1074 | |
| 1075 | monotonic[0] = trace_clock_read64(); |
| 1076 | ret = clock_gettime(CLOCK_REALTIME, &rts); |
| 1077 | if (ret < 0) |
| 1078 | return 0; |
| 1079 | monotonic[1] = trace_clock_read64(); |
| 1080 | offset = (monotonic[0] + monotonic[1]) >> 1; |
| 1081 | realtime = rts.tv_sec * 1000000000ULL; |
| 1082 | realtime += rts.tv_nsec; |
| 1083 | offset = realtime - offset; |
| 1084 | return offset; |
| 1085 | } |
| 1086 | |
| 1087 | /* |
| 1088 | * Output metadata into this session's metadata buffers. |
| 1089 | */ |
| 1090 | static |
| 1091 | int _ltt_session_metadata_statedump(struct ltt_session *session) |
| 1092 | { |
| 1093 | unsigned char *uuid_c = session->uuid; |
| 1094 | char uuid_s[LTTNG_UST_UUID_STR_LEN], |
| 1095 | clock_uuid_s[LTTNG_UST_UUID_STR_LEN]; |
| 1096 | struct ltt_channel *chan; |
| 1097 | struct ltt_event *event; |
| 1098 | int ret = 0; |
| 1099 | char procname[LTTNG_UST_PROCNAME_LEN] = ""; |
| 1100 | |
| 1101 | if (!CMM_ACCESS_ONCE(session->active)) |
| 1102 | return 0; |
| 1103 | if (session->metadata_dumped) |
| 1104 | goto skip_session; |
| 1105 | if (!session->metadata) { |
| 1106 | DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
| 1107 | return -EPERM; |
| 1108 | } |
| 1109 | |
| 1110 | snprintf(uuid_s, sizeof(uuid_s), |
| 1111 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
| 1112 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], |
| 1113 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], |
| 1114 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], |
| 1115 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); |
| 1116 | |
| 1117 | ret = lttng_metadata_printf(session, |
| 1118 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
| 1119 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" |
| 1120 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" |
| 1121 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" |
| 1122 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
| 1123 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" |
| 1124 | "\n" |
| 1125 | "trace {\n" |
| 1126 | " major = %u;\n" |
| 1127 | " minor = %u;\n" |
| 1128 | " uuid = \"%s\";\n" |
| 1129 | " byte_order = %s;\n" |
| 1130 | " packet.header := struct {\n" |
| 1131 | " uint32_t magic;\n" |
| 1132 | " uint8_t uuid[16];\n" |
| 1133 | " uint32_t stream_id;\n" |
| 1134 | " };\n" |
| 1135 | "};\n\n", |
| 1136 | lttng_alignof(uint8_t) * CHAR_BIT, |
| 1137 | lttng_alignof(uint16_t) * CHAR_BIT, |
| 1138 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 1139 | lttng_alignof(uint64_t) * CHAR_BIT, |
| 1140 | CTF_SPEC_MAJOR, |
| 1141 | CTF_SPEC_MINOR, |
| 1142 | uuid_s, |
| 1143 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 1144 | "be" |
| 1145 | #else |
| 1146 | "le" |
| 1147 | #endif |
| 1148 | ); |
| 1149 | if (ret) |
| 1150 | goto end; |
| 1151 | |
| 1152 | /* ignore error, just use empty string if error. */ |
| 1153 | lttng_ust_getprocname(procname); |
| 1154 | procname[LTTNG_UST_PROCNAME_LEN - 1] = '\0'; |
| 1155 | ret = lttng_metadata_printf(session, |
| 1156 | "env {\n" |
| 1157 | " vpid = %d;\n" |
| 1158 | " procname = \"%s\";\n" |
| 1159 | " domain = \"ust\";\n" |
| 1160 | " tracer_name = \"lttng-ust\";\n" |
| 1161 | " tracer_major = %u;\n" |
| 1162 | " tracer_minor = %u;\n" |
| 1163 | " tracer_patchlevel = %u;\n" |
| 1164 | "};\n\n", |
| 1165 | (int) getpid(), |
| 1166 | procname, |
| 1167 | LTTNG_UST_MAJOR_VERSION, |
| 1168 | LTTNG_UST_MINOR_VERSION, |
| 1169 | LTTNG_UST_PATCHLEVEL_VERSION |
| 1170 | ); |
| 1171 | if (ret) |
| 1172 | goto end; |
| 1173 | |
| 1174 | ret = lttng_metadata_printf(session, |
| 1175 | "clock {\n" |
| 1176 | " name = %s;\n", |
| 1177 | "monotonic" |
| 1178 | ); |
| 1179 | if (ret) |
| 1180 | goto end; |
| 1181 | |
| 1182 | if (!trace_clock_uuid(clock_uuid_s)) { |
| 1183 | ret = lttng_metadata_printf(session, |
| 1184 | " uuid = \"%s\";\n", |
| 1185 | clock_uuid_s |
| 1186 | ); |
| 1187 | if (ret) |
| 1188 | goto end; |
| 1189 | } |
| 1190 | |
| 1191 | ret = lttng_metadata_printf(session, |
| 1192 | " description = \"Monotonic Clock\";\n" |
| 1193 | " freq = %" PRIu64 "; /* Frequency, in Hz */\n" |
| 1194 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" |
| 1195 | " offset = %" PRIu64 ";\n" |
| 1196 | "};\n\n", |
| 1197 | trace_clock_freq(), |
| 1198 | measure_clock_offset() |
| 1199 | ); |
| 1200 | if (ret) |
| 1201 | goto end; |
| 1202 | |
| 1203 | ret = lttng_metadata_printf(session, |
| 1204 | "typealias integer {\n" |
| 1205 | " size = 27; align = 1; signed = false;\n" |
| 1206 | " map = clock.monotonic.value;\n" |
| 1207 | "} := uint27_clock_monotonic_t;\n" |
| 1208 | "\n" |
| 1209 | "typealias integer {\n" |
| 1210 | " size = 32; align = %u; signed = false;\n" |
| 1211 | " map = clock.monotonic.value;\n" |
| 1212 | "} := uint32_clock_monotonic_t;\n" |
| 1213 | "\n" |
| 1214 | "typealias integer {\n" |
| 1215 | " size = 64; align = %u; signed = false;\n" |
| 1216 | " map = clock.monotonic.value;\n" |
| 1217 | "} := uint64_clock_monotonic_t;\n\n", |
| 1218 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 1219 | lttng_alignof(uint64_t) * CHAR_BIT |
| 1220 | ); |
| 1221 | if (ret) |
| 1222 | goto end; |
| 1223 | |
| 1224 | ret = _ltt_stream_packet_context_declare(session); |
| 1225 | if (ret) |
| 1226 | goto end; |
| 1227 | |
| 1228 | ret = _ltt_event_header_declare(session); |
| 1229 | if (ret) |
| 1230 | goto end; |
| 1231 | |
| 1232 | skip_session: |
| 1233 | cds_list_for_each_entry(chan, &session->chan, list) { |
| 1234 | ret = _ltt_channel_metadata_statedump(session, chan); |
| 1235 | if (ret) |
| 1236 | goto end; |
| 1237 | } |
| 1238 | |
| 1239 | cds_list_for_each_entry(event, &session->events, list) { |
| 1240 | ret = _ltt_event_metadata_statedump(session, event->chan, event); |
| 1241 | if (ret) |
| 1242 | goto end; |
| 1243 | } |
| 1244 | session->metadata_dumped = 1; |
| 1245 | end: |
| 1246 | return ret; |
| 1247 | } |
| 1248 | |
| 1249 | void lttng_ust_events_exit(void) |
| 1250 | { |
| 1251 | struct ltt_session *session, *tmpsession; |
| 1252 | |
| 1253 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, list) |
| 1254 | ltt_session_destroy(session); |
| 1255 | } |
| 1256 | |
| 1257 | /* WILDCARDS */ |
| 1258 | |
| 1259 | static |
| 1260 | int wildcard_same_loglevel(struct wildcard_entry *e, |
| 1261 | enum lttng_ust_loglevel_type loglevel_type, |
| 1262 | int loglevel) |
| 1263 | { |
| 1264 | if (e->loglevel_type == loglevel_type && e->loglevel == loglevel) |
| 1265 | return 1; |
| 1266 | else |
| 1267 | return 0; |
| 1268 | } |
| 1269 | |
| 1270 | #if 0 |
| 1271 | static |
| 1272 | int wildcard_is_within(struct wildcard_entry *e, |
| 1273 | enum lttng_ust_loglevel_type loglevel_type, |
| 1274 | int loglevel) |
| 1275 | { |
| 1276 | if (e->loglevel_type == LTTNG_UST_LOGLEVEL_ALL |
| 1277 | || e->loglevel == -1) |
| 1278 | return 1; |
| 1279 | switch (e->loglevel_type) { |
| 1280 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 1281 | switch (loglevel_type) { |
| 1282 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 1283 | if (e->loglevel >= loglevel) |
| 1284 | return 1; |
| 1285 | else |
| 1286 | return 0; |
| 1287 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 1288 | if (e->loglevel <= 0 && loglevel == 0) |
| 1289 | return 1; |
| 1290 | else |
| 1291 | return 0; |
| 1292 | } |
| 1293 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 1294 | switch (loglevel_type) { |
| 1295 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 1296 | if (loglevel <= 0) |
| 1297 | return 1; |
| 1298 | else |
| 1299 | return 0; |
| 1300 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 1301 | if (e->loglevel == loglevel) |
| 1302 | return 1; |
| 1303 | else |
| 1304 | return 0; |
| 1305 | } |
| 1306 | } |
| 1307 | } |
| 1308 | #endif |
| 1309 | |
| 1310 | /* |
| 1311 | * Add the wildcard to the wildcard list. Must be called with |
| 1312 | * ust lock held. |
| 1313 | */ |
| 1314 | static |
| 1315 | struct session_wildcard *add_wildcard(struct ltt_channel *chan, |
| 1316 | struct lttng_ust_event *event_param) |
| 1317 | { |
| 1318 | struct wildcard_entry *e; |
| 1319 | struct session_wildcard *sw; |
| 1320 | size_t name_len = strlen(event_param->name) + 1; |
| 1321 | int found = 0; |
| 1322 | |
| 1323 | /* |
| 1324 | * Try to find global wildcard entry. Given that this is shared |
| 1325 | * across all sessions, we need to check for exact loglevel |
| 1326 | * match, not just whether contained within the existing ones. |
| 1327 | */ |
| 1328 | cds_list_for_each_entry(e, &wildcard_list, list) { |
| 1329 | if (!strncmp(event_param->name, e->name, |
| 1330 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
| 1331 | if (wildcard_same_loglevel(e, |
| 1332 | event_param->loglevel_type, |
| 1333 | event_param->loglevel)) { |
| 1334 | found = 1; |
| 1335 | break; |
| 1336 | } |
| 1337 | } |
| 1338 | } |
| 1339 | |
| 1340 | if (!found) { |
| 1341 | /* |
| 1342 | * Create global wildcard entry if not found. Using |
| 1343 | * zmalloc here to allocate a variable length element. |
| 1344 | * Could cause some memory fragmentation if overused. |
| 1345 | */ |
| 1346 | e = zmalloc(sizeof(struct wildcard_entry) + name_len); |
| 1347 | if (!e) |
| 1348 | return ERR_PTR(-ENOMEM); |
| 1349 | memcpy(&e->name[0], event_param->name, name_len); |
| 1350 | cds_list_add(&e->list, &wildcard_list); |
| 1351 | CDS_INIT_LIST_HEAD(&e->session_list); |
| 1352 | } |
| 1353 | |
| 1354 | /* session wildcard */ |
| 1355 | cds_list_for_each_entry(sw, &e->session_list, session_list) { |
| 1356 | if (chan == sw->chan) { |
| 1357 | DBG("wildcard %s busy for this channel", |
| 1358 | event_param->name); |
| 1359 | return ERR_PTR(-EEXIST); /* Already there */ |
| 1360 | } |
| 1361 | } |
| 1362 | sw = zmalloc(sizeof(struct session_wildcard)); |
| 1363 | if (!sw) |
| 1364 | return ERR_PTR(-ENOMEM); |
| 1365 | sw->chan = chan; |
| 1366 | sw->enabled = 1; |
| 1367 | memcpy(&sw->event_param, event_param, sizeof(sw->event_param)); |
| 1368 | sw->event_param.instrumentation = LTTNG_UST_TRACEPOINT; |
| 1369 | sw->event_param.loglevel_type = event_param->loglevel_type; |
| 1370 | sw->event_param.loglevel = event_param->loglevel; |
| 1371 | CDS_INIT_LIST_HEAD(&sw->events); |
| 1372 | cds_list_add(&sw->list, &chan->session->wildcards); |
| 1373 | cds_list_add(&sw->session_list, &e->session_list); |
| 1374 | sw->entry = e; |
| 1375 | ltt_probes_create_wildcard_events(e, sw); |
| 1376 | return sw; |
| 1377 | } |
| 1378 | |
| 1379 | /* |
| 1380 | * Remove the wildcard from the wildcard list. Must be called with |
| 1381 | * ust_lock held. Only called at session teardown. |
| 1382 | */ |
| 1383 | static |
| 1384 | void _remove_wildcard(struct session_wildcard *wildcard) |
| 1385 | { |
| 1386 | struct ltt_event *ev, *tmp; |
| 1387 | |
| 1388 | /* |
| 1389 | * Just remove the events owned (for enable/disable) by this |
| 1390 | * wildcard from the list. The session teardown will take care |
| 1391 | * of freeing the event memory. |
| 1392 | */ |
| 1393 | cds_list_for_each_entry_safe(ev, tmp, &wildcard->events, |
| 1394 | wildcard_list) { |
| 1395 | cds_list_del(&ev->wildcard_list); |
| 1396 | } |
| 1397 | cds_list_del(&wildcard->session_list); |
| 1398 | cds_list_del(&wildcard->list); |
| 1399 | if (cds_list_empty(&wildcard->entry->session_list)) { |
| 1400 | cds_list_del(&wildcard->entry->list); |
| 1401 | free(wildcard->entry); |
| 1402 | } |
| 1403 | free(wildcard); |
| 1404 | } |
| 1405 | |
| 1406 | int ltt_wildcard_create(struct ltt_channel *chan, |
| 1407 | struct lttng_ust_event *event_param, |
| 1408 | struct session_wildcard **_sw) |
| 1409 | { |
| 1410 | struct session_wildcard *sw; |
| 1411 | |
| 1412 | sw = add_wildcard(chan, event_param); |
| 1413 | if (!sw || IS_ERR(sw)) { |
| 1414 | return PTR_ERR(sw); |
| 1415 | } |
| 1416 | *_sw = sw; |
| 1417 | return 0; |
| 1418 | } |
| 1419 | |
| 1420 | static |
| 1421 | void _ltt_wildcard_destroy(struct session_wildcard *sw) |
| 1422 | { |
| 1423 | _remove_wildcard(sw); |
| 1424 | } |
| 1425 | |
| 1426 | int ltt_wildcard_enable(struct session_wildcard *wildcard) |
| 1427 | { |
| 1428 | struct ltt_event *ev; |
| 1429 | int ret; |
| 1430 | |
| 1431 | if (wildcard->enabled) |
| 1432 | return -EEXIST; |
| 1433 | cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) { |
| 1434 | ret = ltt_event_enable(ev); |
| 1435 | if (ret) { |
| 1436 | DBG("Error: enable error.\n"); |
| 1437 | return ret; |
| 1438 | } |
| 1439 | } |
| 1440 | wildcard->enabled = 1; |
| 1441 | return 0; |
| 1442 | } |
| 1443 | |
| 1444 | int ltt_wildcard_disable(struct session_wildcard *wildcard) |
| 1445 | { |
| 1446 | struct ltt_event *ev; |
| 1447 | int ret; |
| 1448 | |
| 1449 | if (!wildcard->enabled) |
| 1450 | return -EEXIST; |
| 1451 | cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) { |
| 1452 | ret = ltt_event_disable(ev); |
| 1453 | if (ret) { |
| 1454 | DBG("Error: disable error.\n"); |
| 1455 | return ret; |
| 1456 | } |
| 1457 | } |
| 1458 | wildcard->enabled = 0; |
| 1459 | return 0; |
| 1460 | } |