| 1 | /* |
| 2 | * ltt-events.c |
| 3 | * |
| 4 | * Holds LTTng per-session event registry. |
| 5 | * |
| 6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 7 | * |
| 8 | * This library is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU Lesser General Public |
| 10 | * License as published by the Free Software Foundation; only |
| 11 | * version 2.1 of the License. |
| 12 | * |
| 13 | * This library is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | * Lesser General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU Lesser General Public |
| 19 | * License along with this library; if not, write to the Free Software |
| 20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 21 | */ |
| 22 | |
| 23 | #define _GNU_SOURCE |
| 24 | #include <stdio.h> |
| 25 | #include <urcu/list.h> |
| 26 | #include <urcu/hlist.h> |
| 27 | #include <pthread.h> |
| 28 | #include <errno.h> |
| 29 | #include <sys/shm.h> |
| 30 | #include <sys/ipc.h> |
| 31 | #include <stdint.h> |
| 32 | #include <stddef.h> |
| 33 | #include <inttypes.h> |
| 34 | #include <time.h> |
| 35 | #include <lttng/ust-endian.h> |
| 36 | #include "clock.h" |
| 37 | |
| 38 | #include <urcu-bp.h> |
| 39 | #include <urcu/compiler.h> |
| 40 | #include <urcu/uatomic.h> |
| 41 | #include <urcu/arch.h> |
| 42 | |
| 43 | #include <lttng/tracepoint.h> |
| 44 | #include <lttng/ust-events.h> |
| 45 | |
| 46 | #include <usterr-signal-safe.h> |
| 47 | #include <helper.h> |
| 48 | #include "error.h" |
| 49 | #include "compat.h" |
| 50 | #include "lttng-ust-uuid.h" |
| 51 | |
| 52 | #include "tracepoint-internal.h" |
| 53 | #include "ltt-tracer.h" |
| 54 | #include "ltt-tracer-core.h" |
| 55 | #include "wait.h" |
| 56 | #include "../libringbuffer/shm.h" |
| 57 | #include "jhash.h" |
| 58 | |
| 59 | /* |
| 60 | * The sessions mutex is the centralized mutex across UST tracing |
| 61 | * control and probe registration. All operations within this file are |
| 62 | * called by the communication thread, under ust_lock protection. |
| 63 | */ |
| 64 | static pthread_mutex_t sessions_mutex = PTHREAD_MUTEX_INITIALIZER; |
| 65 | |
| 66 | void ust_lock(void) |
| 67 | { |
| 68 | pthread_mutex_lock(&sessions_mutex); |
| 69 | } |
| 70 | |
| 71 | void ust_unlock(void) |
| 72 | { |
| 73 | pthread_mutex_unlock(&sessions_mutex); |
| 74 | } |
| 75 | |
| 76 | static CDS_LIST_HEAD(sessions); |
| 77 | |
| 78 | /* |
| 79 | * Wildcard list, containing the active wildcards. |
| 80 | * Protected by ust lock. |
| 81 | */ |
| 82 | static CDS_LIST_HEAD(wildcard_list); |
| 83 | |
| 84 | /* |
| 85 | * Pending probes hash table, containing the registered ltt events for |
| 86 | * which tracepoint probes are still missing. Protected by the sessions |
| 87 | * mutex. |
| 88 | */ |
| 89 | #define PENDING_PROBE_HASH_BITS 6 |
| 90 | #define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS) |
| 91 | static struct cds_hlist_head pending_probe_table[PENDING_PROBE_HASH_SIZE]; |
| 92 | |
| 93 | struct ust_pending_probe { |
| 94 | struct ltt_event *event; |
| 95 | struct cds_hlist_node node; |
| 96 | enum lttng_ust_loglevel_type loglevel_type; |
| 97 | int loglevel; |
| 98 | char name[]; |
| 99 | }; |
| 100 | |
| 101 | static void _ltt_event_destroy(struct ltt_event *event); |
| 102 | static void _ltt_wildcard_destroy(struct session_wildcard *sw); |
| 103 | static void _ltt_channel_destroy(struct ltt_channel *chan); |
| 104 | static int _ltt_event_unregister(struct ltt_event *event); |
| 105 | static |
| 106 | int _ltt_event_metadata_statedump(struct ltt_session *session, |
| 107 | struct ltt_channel *chan, |
| 108 | struct ltt_event *event); |
| 109 | static |
| 110 | int _ltt_session_metadata_statedump(struct ltt_session *session); |
| 111 | |
| 112 | int ltt_loglevel_match(const struct lttng_event_desc *desc, |
| 113 | enum lttng_ust_loglevel_type req_type, |
| 114 | int req_loglevel) |
| 115 | { |
| 116 | int ev_loglevel; |
| 117 | |
| 118 | if (req_type == LTTNG_UST_LOGLEVEL_ALL) |
| 119 | return 1; |
| 120 | if (!desc->loglevel) |
| 121 | ev_loglevel = TRACE_DEFAULT; |
| 122 | else |
| 123 | ev_loglevel = *(*desc->loglevel); |
| 124 | switch (req_type) { |
| 125 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 126 | if (ev_loglevel <= req_loglevel || req_loglevel == -1) |
| 127 | return 1; |
| 128 | else |
| 129 | return 0; |
| 130 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 131 | if (ev_loglevel == req_loglevel || req_loglevel == -1) |
| 132 | return 1; |
| 133 | else |
| 134 | return 0; |
| 135 | case LTTNG_UST_LOGLEVEL_ALL: |
| 136 | default: |
| 137 | return 1; |
| 138 | } |
| 139 | } |
| 140 | |
| 141 | /* |
| 142 | * Return wildcard for a given event name if the event name match the |
| 143 | * one of the wildcards. |
| 144 | * Must be called with ust lock held. |
| 145 | * Returns NULL if not present. |
| 146 | */ |
| 147 | static |
| 148 | struct wildcard_entry *match_wildcard(const struct lttng_event_desc *desc) |
| 149 | { |
| 150 | struct wildcard_entry *e; |
| 151 | |
| 152 | cds_list_for_each_entry(e, &wildcard_list, list) { |
| 153 | /* If only contain '*' */ |
| 154 | if (strlen(e->name) == 1) |
| 155 | goto possible_match; |
| 156 | /* Compare excluding final '*' */ |
| 157 | if (!strncmp(desc->name, e->name, strlen(e->name) - 1)) |
| 158 | goto possible_match; |
| 159 | continue; /* goto next, no match */ |
| 160 | possible_match: |
| 161 | if (ltt_loglevel_match(desc, |
| 162 | e->loglevel_type, |
| 163 | e->loglevel)) { |
| 164 | return e; |
| 165 | } |
| 166 | /* no match, loop to next */ |
| 167 | } |
| 168 | return NULL; |
| 169 | } |
| 170 | |
| 171 | /* |
| 172 | * called at event creation if probe is missing. |
| 173 | * called with session mutex held. |
| 174 | */ |
| 175 | static |
| 176 | int add_pending_probe(struct ltt_event *event, const char *name, |
| 177 | enum lttng_ust_loglevel_type loglevel_type, |
| 178 | int loglevel) |
| 179 | { |
| 180 | struct cds_hlist_head *head; |
| 181 | struct ust_pending_probe *e; |
| 182 | size_t name_len = strlen(name) + 1; |
| 183 | uint32_t hash; |
| 184 | |
| 185 | if (name_len > LTTNG_UST_SYM_NAME_LEN) { |
| 186 | WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN); |
| 187 | name_len = LTTNG_UST_SYM_NAME_LEN; |
| 188 | } |
| 189 | hash = jhash(name, name_len - 1, 0); |
| 190 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; |
| 191 | e = zmalloc(sizeof(struct ust_pending_probe) + name_len); |
| 192 | if (!e) |
| 193 | return -ENOMEM; |
| 194 | memcpy(&e->name[0], name, name_len); |
| 195 | e->name[name_len - 1] = '\0'; |
| 196 | e->loglevel_type = loglevel_type; |
| 197 | e->loglevel = loglevel; |
| 198 | cds_hlist_add_head(&e->node, head); |
| 199 | e->event = event; |
| 200 | event->pending_probe = e; |
| 201 | return 0; |
| 202 | } |
| 203 | |
| 204 | /* |
| 205 | * remove a pending probe. called when at event teardown and when an |
| 206 | * event is fixed (probe is loaded). |
| 207 | * called with session mutex held. |
| 208 | */ |
| 209 | static |
| 210 | void remove_pending_probe(struct ust_pending_probe *e) |
| 211 | { |
| 212 | if (!e) |
| 213 | return; |
| 214 | cds_hlist_del(&e->node); |
| 215 | free(e); |
| 216 | } |
| 217 | |
| 218 | /* |
| 219 | * Called at library load: connect the probe on the events pending on |
| 220 | * probe load. |
| 221 | * called with session mutex held. |
| 222 | */ |
| 223 | int pending_probe_fix_events(const struct lttng_event_desc *desc) |
| 224 | { |
| 225 | struct cds_hlist_head *head; |
| 226 | struct cds_hlist_node *node, *p; |
| 227 | struct ust_pending_probe *e; |
| 228 | const char *name = desc->name; |
| 229 | int ret = 0; |
| 230 | struct lttng_ust_event event_param; |
| 231 | size_t name_len = strlen(name) + 1; |
| 232 | uint32_t hash; |
| 233 | |
| 234 | /* Wildcard */ |
| 235 | { |
| 236 | struct wildcard_entry *wildcard; |
| 237 | |
| 238 | wildcard = match_wildcard(desc); |
| 239 | if (strcmp(desc->name, "lttng_ust:metadata") && wildcard) { |
| 240 | struct session_wildcard *sw; |
| 241 | |
| 242 | cds_list_for_each_entry(sw, &wildcard->session_list, |
| 243 | session_list) { |
| 244 | struct ltt_event *ev; |
| 245 | int ret; |
| 246 | |
| 247 | memcpy(&event_param, &sw->event_param, |
| 248 | sizeof(event_param)); |
| 249 | memcpy(event_param.name, |
| 250 | desc->name, |
| 251 | sizeof(event_param.name)); |
| 252 | /* create event */ |
| 253 | ret = ltt_event_create(sw->chan, |
| 254 | &event_param, &ev); |
| 255 | if (ret) { |
| 256 | DBG("Error creating event"); |
| 257 | continue; |
| 258 | } |
| 259 | cds_list_add(&ev->wildcard_list, |
| 260 | &sw->events); |
| 261 | lttng_filter_event_link_bytecode(ev, |
| 262 | sw->filter_bytecode); |
| 263 | } |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | if (name_len > LTTNG_UST_SYM_NAME_LEN) { |
| 268 | WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name, LTTNG_UST_SYM_NAME_LEN); |
| 269 | name_len = LTTNG_UST_SYM_NAME_LEN; |
| 270 | } |
| 271 | hash = jhash(name, name_len - 1, 0); |
| 272 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; |
| 273 | cds_hlist_for_each_entry_safe(e, node, p, head, node) { |
| 274 | struct ltt_event *event; |
| 275 | struct ltt_channel *chan; |
| 276 | |
| 277 | if (!ltt_loglevel_match(desc, |
| 278 | e->loglevel_type, |
| 279 | e->loglevel)) { |
| 280 | continue; |
| 281 | } |
| 282 | if (strncmp(name, e->name, LTTNG_UST_SYM_NAME_LEN - 1)) { |
| 283 | continue; |
| 284 | } |
| 285 | event = e->event; |
| 286 | chan = event->chan; |
| 287 | assert(!event->desc); |
| 288 | event->desc = desc; |
| 289 | event->pending_probe = NULL; |
| 290 | remove_pending_probe(e); |
| 291 | ret |= __tracepoint_probe_register(name, |
| 292 | event->desc->probe_callback, |
| 293 | event, event->desc->signature); |
| 294 | if (ret) |
| 295 | continue; |
| 296 | event->id = chan->free_event_id++; |
| 297 | ret |= _ltt_event_metadata_statedump(chan->session, chan, |
| 298 | event); |
| 299 | lttng_filter_event_link_bytecode(event, |
| 300 | event->filter_bytecode); |
| 301 | } |
| 302 | return ret; |
| 303 | } |
| 304 | |
| 305 | void synchronize_trace(void) |
| 306 | { |
| 307 | synchronize_rcu(); |
| 308 | } |
| 309 | |
| 310 | struct ltt_session *ltt_session_create(void) |
| 311 | { |
| 312 | struct ltt_session *session; |
| 313 | int ret; |
| 314 | |
| 315 | session = zmalloc(sizeof(struct ltt_session)); |
| 316 | if (!session) |
| 317 | return NULL; |
| 318 | CDS_INIT_LIST_HEAD(&session->chan); |
| 319 | CDS_INIT_LIST_HEAD(&session->events); |
| 320 | CDS_INIT_LIST_HEAD(&session->wildcards); |
| 321 | ret = lttng_ust_uuid_generate(session->uuid); |
| 322 | if (ret != 0) { |
| 323 | session->uuid[0] = '\0'; |
| 324 | } |
| 325 | cds_list_add(&session->list, &sessions); |
| 326 | return session; |
| 327 | } |
| 328 | |
| 329 | void ltt_session_destroy(struct ltt_session *session) |
| 330 | { |
| 331 | struct ltt_channel *chan, *tmpchan; |
| 332 | struct ltt_event *event, *tmpevent; |
| 333 | struct session_wildcard *wildcard, *tmpwildcard; |
| 334 | int ret; |
| 335 | |
| 336 | CMM_ACCESS_ONCE(session->active) = 0; |
| 337 | cds_list_for_each_entry(event, &session->events, list) { |
| 338 | ret = _ltt_event_unregister(event); |
| 339 | WARN_ON(ret); |
| 340 | } |
| 341 | synchronize_trace(); /* Wait for in-flight events to complete */ |
| 342 | cds_list_for_each_entry_safe(wildcard, tmpwildcard, &session->wildcards, list) |
| 343 | _ltt_wildcard_destroy(wildcard); |
| 344 | cds_list_for_each_entry_safe(event, tmpevent, &session->events, list) |
| 345 | _ltt_event_destroy(event); |
| 346 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list) |
| 347 | _ltt_channel_destroy(chan); |
| 348 | cds_list_del(&session->list); |
| 349 | free(session); |
| 350 | } |
| 351 | |
| 352 | int ltt_session_enable(struct ltt_session *session) |
| 353 | { |
| 354 | int ret = 0; |
| 355 | struct ltt_channel *chan; |
| 356 | |
| 357 | if (session->active) { |
| 358 | ret = -EBUSY; |
| 359 | goto end; |
| 360 | } |
| 361 | |
| 362 | /* |
| 363 | * Snapshot the number of events per channel to know the type of header |
| 364 | * we need to use. |
| 365 | */ |
| 366 | cds_list_for_each_entry(chan, &session->chan, list) { |
| 367 | if (chan->header_type) |
| 368 | continue; /* don't change it if session stop/restart */ |
| 369 | if (chan->free_event_id < 31) |
| 370 | chan->header_type = 1; /* compact */ |
| 371 | else |
| 372 | chan->header_type = 2; /* large */ |
| 373 | } |
| 374 | |
| 375 | CMM_ACCESS_ONCE(session->active) = 1; |
| 376 | CMM_ACCESS_ONCE(session->been_active) = 1; |
| 377 | ret = _ltt_session_metadata_statedump(session); |
| 378 | if (ret) |
| 379 | CMM_ACCESS_ONCE(session->active) = 0; |
| 380 | end: |
| 381 | return ret; |
| 382 | } |
| 383 | |
| 384 | int ltt_session_disable(struct ltt_session *session) |
| 385 | { |
| 386 | int ret = 0; |
| 387 | |
| 388 | if (!session->active) { |
| 389 | ret = -EBUSY; |
| 390 | goto end; |
| 391 | } |
| 392 | CMM_ACCESS_ONCE(session->active) = 0; |
| 393 | end: |
| 394 | return ret; |
| 395 | } |
| 396 | |
| 397 | int ltt_channel_enable(struct ltt_channel *channel) |
| 398 | { |
| 399 | int old; |
| 400 | |
| 401 | if (channel == channel->session->metadata) |
| 402 | return -EPERM; |
| 403 | old = uatomic_xchg(&channel->enabled, 1); |
| 404 | if (old) |
| 405 | return -EEXIST; |
| 406 | return 0; |
| 407 | } |
| 408 | |
| 409 | int ltt_channel_disable(struct ltt_channel *channel) |
| 410 | { |
| 411 | int old; |
| 412 | |
| 413 | if (channel == channel->session->metadata) |
| 414 | return -EPERM; |
| 415 | old = uatomic_xchg(&channel->enabled, 0); |
| 416 | if (!old) |
| 417 | return -EEXIST; |
| 418 | return 0; |
| 419 | } |
| 420 | |
| 421 | int ltt_event_enable(struct ltt_event *event) |
| 422 | { |
| 423 | int old; |
| 424 | |
| 425 | if (event->chan == event->chan->session->metadata) |
| 426 | return -EPERM; |
| 427 | old = uatomic_xchg(&event->enabled, 1); |
| 428 | if (old) |
| 429 | return -EEXIST; |
| 430 | return 0; |
| 431 | } |
| 432 | |
| 433 | int ltt_event_disable(struct ltt_event *event) |
| 434 | { |
| 435 | int old; |
| 436 | |
| 437 | if (event->chan == event->chan->session->metadata) |
| 438 | return -EPERM; |
| 439 | old = uatomic_xchg(&event->enabled, 0); |
| 440 | if (!old) |
| 441 | return -EEXIST; |
| 442 | return 0; |
| 443 | } |
| 444 | |
| 445 | struct ltt_channel *ltt_channel_create(struct ltt_session *session, |
| 446 | const char *transport_name, |
| 447 | void *buf_addr, |
| 448 | size_t subbuf_size, size_t num_subbuf, |
| 449 | unsigned int switch_timer_interval, |
| 450 | unsigned int read_timer_interval, |
| 451 | int **shm_fd, int **wait_fd, |
| 452 | uint64_t **memory_map_size, |
| 453 | struct ltt_channel *chan_priv_init) |
| 454 | { |
| 455 | struct ltt_channel *chan = NULL; |
| 456 | struct ltt_transport *transport; |
| 457 | |
| 458 | if (session->been_active) |
| 459 | goto active; /* Refuse to add channel to active session */ |
| 460 | transport = ltt_transport_find(transport_name); |
| 461 | if (!transport) { |
| 462 | DBG("LTTng transport %s not found\n", |
| 463 | transport_name); |
| 464 | goto notransport; |
| 465 | } |
| 466 | chan_priv_init->id = session->free_chan_id++; |
| 467 | chan_priv_init->session = session; |
| 468 | /* |
| 469 | * Note: the channel creation op already writes into the packet |
| 470 | * headers. Therefore the "chan" information used as input |
| 471 | * should be already accessible. |
| 472 | */ |
| 473 | chan = transport->ops.channel_create(transport_name, buf_addr, |
| 474 | subbuf_size, num_subbuf, switch_timer_interval, |
| 475 | read_timer_interval, shm_fd, wait_fd, |
| 476 | memory_map_size, chan_priv_init); |
| 477 | if (!chan) |
| 478 | goto create_error; |
| 479 | chan->enabled = 1; |
| 480 | chan->ops = &transport->ops; |
| 481 | cds_list_add(&chan->list, &session->chan); |
| 482 | return chan; |
| 483 | |
| 484 | create_error: |
| 485 | notransport: |
| 486 | active: |
| 487 | return NULL; |
| 488 | } |
| 489 | |
| 490 | /* |
| 491 | * Only used internally at session destruction. |
| 492 | */ |
| 493 | static |
| 494 | void _ltt_channel_destroy(struct ltt_channel *chan) |
| 495 | { |
| 496 | cds_list_del(&chan->list); |
| 497 | lttng_destroy_context(chan->ctx); |
| 498 | chan->ops->channel_destroy(chan); |
| 499 | } |
| 500 | |
| 501 | /* |
| 502 | * Supports event creation while tracing session is active. |
| 503 | */ |
| 504 | int ltt_event_create(struct ltt_channel *chan, |
| 505 | struct lttng_ust_event *event_param, |
| 506 | struct ltt_event **_event) |
| 507 | { |
| 508 | const struct lttng_event_desc *desc = NULL; /* silence gcc */ |
| 509 | struct ltt_event *event; |
| 510 | int ret = 0; |
| 511 | |
| 512 | if (chan->used_event_id == -1U) { |
| 513 | ret = -ENOMEM; |
| 514 | goto full; |
| 515 | } |
| 516 | /* |
| 517 | * This is O(n^2) (for each event, the loop is called at event |
| 518 | * creation). Might require a hash if we have lots of events. |
| 519 | */ |
| 520 | cds_list_for_each_entry(event, &chan->session->events, list) { |
| 521 | if (event->desc && !strncmp(event->desc->name, |
| 522 | event_param->name, |
| 523 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
| 524 | ret = -EEXIST; |
| 525 | goto exist; |
| 526 | } |
| 527 | } |
| 528 | |
| 529 | /* |
| 530 | * Check if loglevel match. Refuse to connect event if not. |
| 531 | */ |
| 532 | if (event_param->instrumentation == LTTNG_UST_TRACEPOINT) { |
| 533 | desc = ltt_event_get(event_param->name); |
| 534 | if (desc) { |
| 535 | if (!ltt_loglevel_match(desc, |
| 536 | event_param->loglevel_type, |
| 537 | event_param->loglevel)) { |
| 538 | ret = -EPERM; |
| 539 | goto no_loglevel_match; |
| 540 | } |
| 541 | } |
| 542 | /* |
| 543 | * If descriptor is not there, it will be added to |
| 544 | * pending probes. |
| 545 | */ |
| 546 | } |
| 547 | event = zmalloc(sizeof(struct ltt_event)); |
| 548 | if (!event) { |
| 549 | ret = -ENOMEM; |
| 550 | goto cache_error; |
| 551 | } |
| 552 | event->chan = chan; |
| 553 | /* |
| 554 | * used_event_id counts the maximum number of event IDs that can |
| 555 | * register if all probes register. |
| 556 | */ |
| 557 | chan->used_event_id++; |
| 558 | event->enabled = 1; |
| 559 | event->instrumentation = event_param->instrumentation; |
| 560 | /* Populate ltt_event structure before tracepoint registration. */ |
| 561 | cmm_smp_wmb(); |
| 562 | switch (event_param->instrumentation) { |
| 563 | case LTTNG_UST_TRACEPOINT: |
| 564 | event->desc = desc; |
| 565 | if (event->desc) { |
| 566 | ret = __tracepoint_probe_register(event_param->name, |
| 567 | event->desc->probe_callback, |
| 568 | event, event->desc->signature); |
| 569 | if (ret) |
| 570 | goto register_error; |
| 571 | event->id = chan->free_event_id++; |
| 572 | } else { |
| 573 | /* |
| 574 | * If the probe is not present, event->desc stays NULL, |
| 575 | * waiting for the probe to register, and the event->id |
| 576 | * stays unallocated. |
| 577 | */ |
| 578 | ret = add_pending_probe(event, event_param->name, |
| 579 | event_param->loglevel_type, |
| 580 | event_param->loglevel); |
| 581 | if (ret) |
| 582 | goto add_pending_error; |
| 583 | } |
| 584 | break; |
| 585 | default: |
| 586 | WARN_ON_ONCE(1); |
| 587 | } |
| 588 | if (event->desc) { |
| 589 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); |
| 590 | if (ret) |
| 591 | goto statedump_error; |
| 592 | } |
| 593 | cds_list_add(&event->list, &chan->session->events); |
| 594 | *_event = event; |
| 595 | return 0; |
| 596 | |
| 597 | statedump_error: |
| 598 | if (event->desc) { |
| 599 | WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name, |
| 600 | event->desc->probe_callback, |
| 601 | event)); |
| 602 | ltt_event_put(event->desc); |
| 603 | } |
| 604 | add_pending_error: |
| 605 | register_error: |
| 606 | free(event); |
| 607 | cache_error: |
| 608 | no_loglevel_match: |
| 609 | exist: |
| 610 | full: |
| 611 | return ret; |
| 612 | } |
| 613 | |
| 614 | /* |
| 615 | * Only used internally at session destruction. |
| 616 | */ |
| 617 | int _ltt_event_unregister(struct ltt_event *event) |
| 618 | { |
| 619 | int ret = -EINVAL; |
| 620 | |
| 621 | switch (event->instrumentation) { |
| 622 | case LTTNG_UST_TRACEPOINT: |
| 623 | if (event->desc) { |
| 624 | ret = __tracepoint_probe_unregister(event->desc->name, |
| 625 | event->desc->probe_callback, |
| 626 | event); |
| 627 | if (ret) |
| 628 | return ret; |
| 629 | } else { |
| 630 | remove_pending_probe(event->pending_probe); |
| 631 | ret = 0; |
| 632 | } |
| 633 | break; |
| 634 | default: |
| 635 | WARN_ON_ONCE(1); |
| 636 | } |
| 637 | return ret; |
| 638 | } |
| 639 | |
| 640 | /* |
| 641 | * Only used internally at session destruction. |
| 642 | */ |
| 643 | static |
| 644 | void _ltt_event_destroy(struct ltt_event *event) |
| 645 | { |
| 646 | switch (event->instrumentation) { |
| 647 | case LTTNG_UST_TRACEPOINT: |
| 648 | if (event->desc) { |
| 649 | ltt_event_put(event->desc); |
| 650 | } |
| 651 | break; |
| 652 | default: |
| 653 | WARN_ON_ONCE(1); |
| 654 | } |
| 655 | cds_list_del(&event->list); |
| 656 | lttng_destroy_context(event->ctx); |
| 657 | free(event->filter_bytecode); |
| 658 | free(event->filter_data); |
| 659 | free(event); |
| 660 | } |
| 661 | |
| 662 | /* |
| 663 | * We have exclusive access to our metadata buffer (protected by the |
| 664 | * ust_lock), so we can do racy operations such as looking for |
| 665 | * remaining space left in packet and write, since mutual exclusion |
| 666 | * protects us from concurrent writes. |
| 667 | */ |
| 668 | int lttng_metadata_printf(struct ltt_session *session, |
| 669 | const char *fmt, ...) |
| 670 | { |
| 671 | struct lttng_ust_lib_ring_buffer_ctx ctx; |
| 672 | struct ltt_channel *chan = session->metadata; |
| 673 | char *str = NULL; |
| 674 | int ret = 0, waitret; |
| 675 | size_t len, reserve_len, pos; |
| 676 | va_list ap; |
| 677 | |
| 678 | WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active)); |
| 679 | |
| 680 | va_start(ap, fmt); |
| 681 | ret = vasprintf(&str, fmt, ap); |
| 682 | va_end(ap); |
| 683 | if (ret < 0) |
| 684 | return -ENOMEM; |
| 685 | |
| 686 | len = strlen(str); |
| 687 | pos = 0; |
| 688 | |
| 689 | for (pos = 0; pos < len; pos += reserve_len) { |
| 690 | reserve_len = min_t(size_t, |
| 691 | chan->ops->packet_avail_size(chan->chan, chan->handle), |
| 692 | len - pos); |
| 693 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, |
| 694 | sizeof(char), -1, chan->handle); |
| 695 | /* |
| 696 | * We don't care about metadata buffer's records lost |
| 697 | * count, because we always retry here. Report error if |
| 698 | * we need to bail out after timeout or being |
| 699 | * interrupted. |
| 700 | */ |
| 701 | waitret = wait_cond_interruptible_timeout( |
| 702 | ({ |
| 703 | ret = chan->ops->event_reserve(&ctx, 0); |
| 704 | ret != -ENOBUFS || !ret; |
| 705 | }), |
| 706 | LTTNG_METADATA_TIMEOUT_MSEC); |
| 707 | if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) { |
| 708 | DBG("LTTng: Failure to write metadata to buffers (%s)\n", |
| 709 | waitret == -EINTR ? "interrupted" : |
| 710 | (ret == -ENOBUFS ? "timeout" : "I/O error")); |
| 711 | if (waitret == -EINTR) |
| 712 | ret = waitret; |
| 713 | goto end; |
| 714 | } |
| 715 | chan->ops->event_write(&ctx, &str[pos], reserve_len); |
| 716 | chan->ops->event_commit(&ctx); |
| 717 | } |
| 718 | end: |
| 719 | free(str); |
| 720 | return ret; |
| 721 | } |
| 722 | |
| 723 | static |
| 724 | int _ltt_field_statedump(struct ltt_session *session, |
| 725 | const struct lttng_event_field *field) |
| 726 | { |
| 727 | int ret = 0; |
| 728 | |
| 729 | if (field->nowrite) |
| 730 | return 0; |
| 731 | |
| 732 | switch (field->type.atype) { |
| 733 | case atype_integer: |
| 734 | ret = lttng_metadata_printf(session, |
| 735 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
| 736 | field->type.u.basic.integer.size, |
| 737 | field->type.u.basic.integer.alignment, |
| 738 | field->type.u.basic.integer.signedness, |
| 739 | (field->type.u.basic.integer.encoding == lttng_encode_none) |
| 740 | ? "none" |
| 741 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) |
| 742 | ? "UTF8" |
| 743 | : "ASCII", |
| 744 | field->type.u.basic.integer.base, |
| 745 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 746 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 747 | #else |
| 748 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 749 | #endif |
| 750 | field->name); |
| 751 | break; |
| 752 | case atype_float: |
| 753 | ret = lttng_metadata_printf(session, |
| 754 | " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n", |
| 755 | field->type.u.basic._float.exp_dig, |
| 756 | field->type.u.basic._float.mant_dig, |
| 757 | field->type.u.basic._float.alignment, |
| 758 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 759 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 760 | #else |
| 761 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 762 | #endif |
| 763 | field->name); |
| 764 | break; |
| 765 | case atype_enum: |
| 766 | ret = lttng_metadata_printf(session, |
| 767 | " %s %s;\n", |
| 768 | field->type.u.basic.enumeration.name, |
| 769 | field->name); |
| 770 | break; |
| 771 | case atype_array: |
| 772 | { |
| 773 | const struct lttng_basic_type *elem_type; |
| 774 | |
| 775 | elem_type = &field->type.u.array.elem_type; |
| 776 | ret = lttng_metadata_printf(session, |
| 777 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
| 778 | elem_type->u.basic.integer.size, |
| 779 | elem_type->u.basic.integer.alignment, |
| 780 | elem_type->u.basic.integer.signedness, |
| 781 | (elem_type->u.basic.integer.encoding == lttng_encode_none) |
| 782 | ? "none" |
| 783 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 784 | ? "UTF8" |
| 785 | : "ASCII", |
| 786 | elem_type->u.basic.integer.base, |
| 787 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 788 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 789 | #else |
| 790 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 791 | #endif |
| 792 | field->name, field->type.u.array.length); |
| 793 | break; |
| 794 | } |
| 795 | case atype_sequence: |
| 796 | { |
| 797 | const struct lttng_basic_type *elem_type; |
| 798 | const struct lttng_basic_type *length_type; |
| 799 | |
| 800 | elem_type = &field->type.u.sequence.elem_type; |
| 801 | length_type = &field->type.u.sequence.length_type; |
| 802 | ret = lttng_metadata_printf(session, |
| 803 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", |
| 804 | length_type->u.basic.integer.size, |
| 805 | (unsigned int) length_type->u.basic.integer.alignment, |
| 806 | length_type->u.basic.integer.signedness, |
| 807 | (length_type->u.basic.integer.encoding == lttng_encode_none) |
| 808 | ? "none" |
| 809 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 810 | ? "UTF8" |
| 811 | : "ASCII"), |
| 812 | length_type->u.basic.integer.base, |
| 813 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 814 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 815 | #else |
| 816 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 817 | #endif |
| 818 | field->name); |
| 819 | if (ret) |
| 820 | return ret; |
| 821 | |
| 822 | ret = lttng_metadata_printf(session, |
| 823 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
| 824 | elem_type->u.basic.integer.size, |
| 825 | (unsigned int) elem_type->u.basic.integer.alignment, |
| 826 | elem_type->u.basic.integer.signedness, |
| 827 | (elem_type->u.basic.integer.encoding == lttng_encode_none) |
| 828 | ? "none" |
| 829 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 830 | ? "UTF8" |
| 831 | : "ASCII"), |
| 832 | elem_type->u.basic.integer.base, |
| 833 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 834 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 835 | #else |
| 836 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 837 | #endif |
| 838 | field->name, |
| 839 | field->name); |
| 840 | break; |
| 841 | } |
| 842 | |
| 843 | case atype_string: |
| 844 | /* Default encoding is UTF8 */ |
| 845 | ret = lttng_metadata_printf(session, |
| 846 | " string%s _%s;\n", |
| 847 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
| 848 | " { encoding = ASCII; }" : "", |
| 849 | field->name); |
| 850 | break; |
| 851 | default: |
| 852 | WARN_ON_ONCE(1); |
| 853 | return -EINVAL; |
| 854 | } |
| 855 | return ret; |
| 856 | } |
| 857 | |
| 858 | static |
| 859 | int _ltt_context_metadata_statedump(struct ltt_session *session, |
| 860 | struct lttng_ctx *ctx) |
| 861 | { |
| 862 | int ret = 0; |
| 863 | int i; |
| 864 | |
| 865 | if (!ctx) |
| 866 | return 0; |
| 867 | for (i = 0; i < ctx->nr_fields; i++) { |
| 868 | const struct lttng_ctx_field *field = &ctx->fields[i]; |
| 869 | |
| 870 | ret = _ltt_field_statedump(session, &field->event_field); |
| 871 | if (ret) |
| 872 | return ret; |
| 873 | } |
| 874 | return ret; |
| 875 | } |
| 876 | |
| 877 | static |
| 878 | int _ltt_fields_metadata_statedump(struct ltt_session *session, |
| 879 | struct ltt_event *event) |
| 880 | { |
| 881 | const struct lttng_event_desc *desc = event->desc; |
| 882 | int ret = 0; |
| 883 | int i; |
| 884 | |
| 885 | for (i = 0; i < desc->nr_fields; i++) { |
| 886 | const struct lttng_event_field *field = &desc->fields[i]; |
| 887 | |
| 888 | ret = _ltt_field_statedump(session, field); |
| 889 | if (ret) |
| 890 | return ret; |
| 891 | } |
| 892 | return ret; |
| 893 | } |
| 894 | |
| 895 | static |
| 896 | int _ltt_event_metadata_statedump(struct ltt_session *session, |
| 897 | struct ltt_channel *chan, |
| 898 | struct ltt_event *event) |
| 899 | { |
| 900 | int ret = 0; |
| 901 | int loglevel = TRACE_DEFAULT; |
| 902 | |
| 903 | if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
| 904 | return 0; |
| 905 | if (chan == session->metadata) |
| 906 | return 0; |
| 907 | /* |
| 908 | * Don't print events for which probe load is pending. |
| 909 | */ |
| 910 | if (!event->desc) |
| 911 | return 0; |
| 912 | |
| 913 | ret = lttng_metadata_printf(session, |
| 914 | "event {\n" |
| 915 | " name = \"%s\";\n" |
| 916 | " id = %u;\n" |
| 917 | " stream_id = %u;\n", |
| 918 | event->desc->name, |
| 919 | event->id, |
| 920 | event->chan->id); |
| 921 | if (ret) |
| 922 | goto end; |
| 923 | |
| 924 | if (event->desc->loglevel) |
| 925 | loglevel = *(*event->desc->loglevel); |
| 926 | |
| 927 | ret = lttng_metadata_printf(session, |
| 928 | " loglevel = %d;\n", |
| 929 | loglevel); |
| 930 | if (ret) |
| 931 | goto end; |
| 932 | |
| 933 | if (event->ctx) { |
| 934 | ret = lttng_metadata_printf(session, |
| 935 | " context := struct {\n"); |
| 936 | if (ret) |
| 937 | goto end; |
| 938 | } |
| 939 | ret = _ltt_context_metadata_statedump(session, event->ctx); |
| 940 | if (ret) |
| 941 | goto end; |
| 942 | if (event->ctx) { |
| 943 | ret = lttng_metadata_printf(session, |
| 944 | " };\n"); |
| 945 | if (ret) |
| 946 | goto end; |
| 947 | } |
| 948 | |
| 949 | ret = lttng_metadata_printf(session, |
| 950 | " fields := struct {\n" |
| 951 | ); |
| 952 | if (ret) |
| 953 | goto end; |
| 954 | |
| 955 | ret = _ltt_fields_metadata_statedump(session, event); |
| 956 | if (ret) |
| 957 | goto end; |
| 958 | |
| 959 | /* |
| 960 | * LTTng space reservation can only reserve multiples of the |
| 961 | * byte size. |
| 962 | */ |
| 963 | ret = lttng_metadata_printf(session, |
| 964 | " };\n" |
| 965 | "};\n\n"); |
| 966 | if (ret) |
| 967 | goto end; |
| 968 | |
| 969 | event->metadata_dumped = 1; |
| 970 | end: |
| 971 | return ret; |
| 972 | |
| 973 | } |
| 974 | |
| 975 | static |
| 976 | int _ltt_channel_metadata_statedump(struct ltt_session *session, |
| 977 | struct ltt_channel *chan) |
| 978 | { |
| 979 | int ret = 0; |
| 980 | |
| 981 | if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
| 982 | return 0; |
| 983 | if (chan == session->metadata) |
| 984 | return 0; |
| 985 | |
| 986 | WARN_ON_ONCE(!chan->header_type); |
| 987 | ret = lttng_metadata_printf(session, |
| 988 | "stream {\n" |
| 989 | " id = %u;\n" |
| 990 | " event.header := %s;\n" |
| 991 | " packet.context := struct packet_context;\n", |
| 992 | chan->id, |
| 993 | chan->header_type == 1 ? "struct event_header_compact" : |
| 994 | "struct event_header_large"); |
| 995 | if (ret) |
| 996 | goto end; |
| 997 | |
| 998 | if (chan->ctx) { |
| 999 | ret = lttng_metadata_printf(session, |
| 1000 | " event.context := struct {\n"); |
| 1001 | if (ret) |
| 1002 | goto end; |
| 1003 | } |
| 1004 | ret = _ltt_context_metadata_statedump(session, chan->ctx); |
| 1005 | if (ret) |
| 1006 | goto end; |
| 1007 | if (chan->ctx) { |
| 1008 | ret = lttng_metadata_printf(session, |
| 1009 | " };\n"); |
| 1010 | if (ret) |
| 1011 | goto end; |
| 1012 | } |
| 1013 | |
| 1014 | ret = lttng_metadata_printf(session, |
| 1015 | "};\n\n"); |
| 1016 | |
| 1017 | chan->metadata_dumped = 1; |
| 1018 | end: |
| 1019 | return ret; |
| 1020 | } |
| 1021 | |
| 1022 | static |
| 1023 | int _ltt_stream_packet_context_declare(struct ltt_session *session) |
| 1024 | { |
| 1025 | return lttng_metadata_printf(session, |
| 1026 | "struct packet_context {\n" |
| 1027 | " uint64_clock_monotonic_t timestamp_begin;\n" |
| 1028 | " uint64_clock_monotonic_t timestamp_end;\n" |
| 1029 | " unsigned long events_discarded;\n" |
| 1030 | " uint32_t content_size;\n" |
| 1031 | " uint32_t packet_size;\n" |
| 1032 | " uint32_t cpu_id;\n" |
| 1033 | "};\n\n" |
| 1034 | ); |
| 1035 | } |
| 1036 | |
| 1037 | /* |
| 1038 | * Compact header: |
| 1039 | * id: range: 0 - 30. |
| 1040 | * id 31 is reserved to indicate an extended header. |
| 1041 | * |
| 1042 | * Large header: |
| 1043 | * id: range: 0 - 65534. |
| 1044 | * id 65535 is reserved to indicate an extended header. |
| 1045 | */ |
| 1046 | static |
| 1047 | int _ltt_event_header_declare(struct ltt_session *session) |
| 1048 | { |
| 1049 | return lttng_metadata_printf(session, |
| 1050 | "struct event_header_compact {\n" |
| 1051 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" |
| 1052 | " variant <id> {\n" |
| 1053 | " struct {\n" |
| 1054 | " uint27_clock_monotonic_t timestamp;\n" |
| 1055 | " } compact;\n" |
| 1056 | " struct {\n" |
| 1057 | " uint32_t id;\n" |
| 1058 | " uint64_clock_monotonic_t timestamp;\n" |
| 1059 | " } extended;\n" |
| 1060 | " } v;\n" |
| 1061 | "} align(%u);\n" |
| 1062 | "\n" |
| 1063 | "struct event_header_large {\n" |
| 1064 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" |
| 1065 | " variant <id> {\n" |
| 1066 | " struct {\n" |
| 1067 | " uint32_clock_monotonic_t timestamp;\n" |
| 1068 | " } compact;\n" |
| 1069 | " struct {\n" |
| 1070 | " uint32_t id;\n" |
| 1071 | " uint64_clock_monotonic_t timestamp;\n" |
| 1072 | " } extended;\n" |
| 1073 | " } v;\n" |
| 1074 | "} align(%u);\n\n", |
| 1075 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 1076 | lttng_alignof(uint16_t) * CHAR_BIT |
| 1077 | ); |
| 1078 | } |
| 1079 | |
| 1080 | /* |
| 1081 | * Approximation of NTP time of day to clock monotonic correlation, |
| 1082 | * taken at start of trace. |
| 1083 | * Yes, this is only an approximation. Yes, we can (and will) do better |
| 1084 | * in future versions. |
| 1085 | */ |
| 1086 | static |
| 1087 | uint64_t measure_clock_offset(void) |
| 1088 | { |
| 1089 | uint64_t offset, monotonic[2], realtime; |
| 1090 | struct timespec rts = { 0, 0 }; |
| 1091 | int ret; |
| 1092 | |
| 1093 | monotonic[0] = trace_clock_read64(); |
| 1094 | ret = clock_gettime(CLOCK_REALTIME, &rts); |
| 1095 | if (ret < 0) |
| 1096 | return 0; |
| 1097 | monotonic[1] = trace_clock_read64(); |
| 1098 | offset = (monotonic[0] + monotonic[1]) >> 1; |
| 1099 | realtime = (uint64_t) rts.tv_sec * 1000000000ULL; |
| 1100 | realtime += rts.tv_nsec; |
| 1101 | offset = realtime - offset; |
| 1102 | return offset; |
| 1103 | } |
| 1104 | |
| 1105 | /* |
| 1106 | * Output metadata into this session's metadata buffers. |
| 1107 | */ |
| 1108 | static |
| 1109 | int _ltt_session_metadata_statedump(struct ltt_session *session) |
| 1110 | { |
| 1111 | unsigned char *uuid_c = session->uuid; |
| 1112 | char uuid_s[LTTNG_UST_UUID_STR_LEN], |
| 1113 | clock_uuid_s[LTTNG_UST_UUID_STR_LEN]; |
| 1114 | struct ltt_channel *chan; |
| 1115 | struct ltt_event *event; |
| 1116 | int ret = 0; |
| 1117 | char procname[LTTNG_UST_PROCNAME_LEN] = ""; |
| 1118 | char hostname[HOST_NAME_MAX]; |
| 1119 | |
| 1120 | if (!CMM_ACCESS_ONCE(session->active)) |
| 1121 | return 0; |
| 1122 | if (session->metadata_dumped) |
| 1123 | goto skip_session; |
| 1124 | if (!session->metadata) { |
| 1125 | DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
| 1126 | return -EPERM; |
| 1127 | } |
| 1128 | |
| 1129 | snprintf(uuid_s, sizeof(uuid_s), |
| 1130 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
| 1131 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], |
| 1132 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], |
| 1133 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], |
| 1134 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); |
| 1135 | |
| 1136 | ret = lttng_metadata_printf(session, |
| 1137 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
| 1138 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" |
| 1139 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" |
| 1140 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" |
| 1141 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
| 1142 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
| 1143 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" |
| 1144 | "\n" |
| 1145 | "trace {\n" |
| 1146 | " major = %u;\n" |
| 1147 | " minor = %u;\n" |
| 1148 | " uuid = \"%s\";\n" |
| 1149 | " byte_order = %s;\n" |
| 1150 | " packet.header := struct {\n" |
| 1151 | " uint32_t magic;\n" |
| 1152 | " uint8_t uuid[16];\n" |
| 1153 | " uint32_t stream_id;\n" |
| 1154 | " };\n" |
| 1155 | "};\n\n", |
| 1156 | lttng_alignof(uint8_t) * CHAR_BIT, |
| 1157 | lttng_alignof(uint16_t) * CHAR_BIT, |
| 1158 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 1159 | lttng_alignof(uint64_t) * CHAR_BIT, |
| 1160 | sizeof(unsigned long) * CHAR_BIT, |
| 1161 | lttng_alignof(unsigned long) * CHAR_BIT, |
| 1162 | CTF_SPEC_MAJOR, |
| 1163 | CTF_SPEC_MINOR, |
| 1164 | uuid_s, |
| 1165 | #if (BYTE_ORDER == BIG_ENDIAN) |
| 1166 | "be" |
| 1167 | #else |
| 1168 | "le" |
| 1169 | #endif |
| 1170 | ); |
| 1171 | if (ret) |
| 1172 | goto end; |
| 1173 | |
| 1174 | /* ignore error, just use empty string if error. */ |
| 1175 | hostname[0] = '\0'; |
| 1176 | ret = gethostname(hostname, sizeof(hostname)); |
| 1177 | if (ret && errno == ENAMETOOLONG) |
| 1178 | hostname[HOST_NAME_MAX - 1] = '\0'; |
| 1179 | lttng_ust_getprocname(procname); |
| 1180 | procname[LTTNG_UST_PROCNAME_LEN - 1] = '\0'; |
| 1181 | ret = lttng_metadata_printf(session, |
| 1182 | "env {\n" |
| 1183 | " hostname = \"%s\";\n" |
| 1184 | " vpid = %d;\n" |
| 1185 | " procname = \"%s\";\n" |
| 1186 | " domain = \"ust\";\n" |
| 1187 | " tracer_name = \"lttng-ust\";\n" |
| 1188 | " tracer_major = %u;\n" |
| 1189 | " tracer_minor = %u;\n" |
| 1190 | " tracer_patchlevel = %u;\n" |
| 1191 | "};\n\n", |
| 1192 | hostname, |
| 1193 | (int) getpid(), |
| 1194 | procname, |
| 1195 | LTTNG_UST_MAJOR_VERSION, |
| 1196 | LTTNG_UST_MINOR_VERSION, |
| 1197 | LTTNG_UST_PATCHLEVEL_VERSION |
| 1198 | ); |
| 1199 | if (ret) |
| 1200 | goto end; |
| 1201 | |
| 1202 | ret = lttng_metadata_printf(session, |
| 1203 | "clock {\n" |
| 1204 | " name = %s;\n", |
| 1205 | "monotonic" |
| 1206 | ); |
| 1207 | if (ret) |
| 1208 | goto end; |
| 1209 | |
| 1210 | if (!trace_clock_uuid(clock_uuid_s)) { |
| 1211 | ret = lttng_metadata_printf(session, |
| 1212 | " uuid = \"%s\";\n", |
| 1213 | clock_uuid_s |
| 1214 | ); |
| 1215 | if (ret) |
| 1216 | goto end; |
| 1217 | } |
| 1218 | |
| 1219 | ret = lttng_metadata_printf(session, |
| 1220 | " description = \"Monotonic Clock\";\n" |
| 1221 | " freq = %" PRIu64 "; /* Frequency, in Hz */\n" |
| 1222 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" |
| 1223 | " offset = %" PRIu64 ";\n" |
| 1224 | "};\n\n", |
| 1225 | trace_clock_freq(), |
| 1226 | measure_clock_offset() |
| 1227 | ); |
| 1228 | if (ret) |
| 1229 | goto end; |
| 1230 | |
| 1231 | ret = lttng_metadata_printf(session, |
| 1232 | "typealias integer {\n" |
| 1233 | " size = 27; align = 1; signed = false;\n" |
| 1234 | " map = clock.monotonic.value;\n" |
| 1235 | "} := uint27_clock_monotonic_t;\n" |
| 1236 | "\n" |
| 1237 | "typealias integer {\n" |
| 1238 | " size = 32; align = %u; signed = false;\n" |
| 1239 | " map = clock.monotonic.value;\n" |
| 1240 | "} := uint32_clock_monotonic_t;\n" |
| 1241 | "\n" |
| 1242 | "typealias integer {\n" |
| 1243 | " size = 64; align = %u; signed = false;\n" |
| 1244 | " map = clock.monotonic.value;\n" |
| 1245 | "} := uint64_clock_monotonic_t;\n\n", |
| 1246 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 1247 | lttng_alignof(uint64_t) * CHAR_BIT |
| 1248 | ); |
| 1249 | if (ret) |
| 1250 | goto end; |
| 1251 | |
| 1252 | ret = _ltt_stream_packet_context_declare(session); |
| 1253 | if (ret) |
| 1254 | goto end; |
| 1255 | |
| 1256 | ret = _ltt_event_header_declare(session); |
| 1257 | if (ret) |
| 1258 | goto end; |
| 1259 | |
| 1260 | skip_session: |
| 1261 | cds_list_for_each_entry(chan, &session->chan, list) { |
| 1262 | ret = _ltt_channel_metadata_statedump(session, chan); |
| 1263 | if (ret) |
| 1264 | goto end; |
| 1265 | } |
| 1266 | |
| 1267 | cds_list_for_each_entry(event, &session->events, list) { |
| 1268 | ret = _ltt_event_metadata_statedump(session, event->chan, event); |
| 1269 | if (ret) |
| 1270 | goto end; |
| 1271 | } |
| 1272 | session->metadata_dumped = 1; |
| 1273 | end: |
| 1274 | return ret; |
| 1275 | } |
| 1276 | |
| 1277 | void lttng_ust_events_exit(void) |
| 1278 | { |
| 1279 | struct ltt_session *session, *tmpsession; |
| 1280 | |
| 1281 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, list) |
| 1282 | ltt_session_destroy(session); |
| 1283 | } |
| 1284 | |
| 1285 | /* WILDCARDS */ |
| 1286 | |
| 1287 | static |
| 1288 | int wildcard_same_loglevel(struct wildcard_entry *e, |
| 1289 | enum lttng_ust_loglevel_type loglevel_type, |
| 1290 | int loglevel) |
| 1291 | { |
| 1292 | if (e->loglevel_type == loglevel_type && e->loglevel == loglevel) |
| 1293 | return 1; |
| 1294 | else |
| 1295 | return 0; |
| 1296 | } |
| 1297 | |
| 1298 | #if 0 |
| 1299 | static |
| 1300 | int wildcard_is_within(struct wildcard_entry *e, |
| 1301 | enum lttng_ust_loglevel_type loglevel_type, |
| 1302 | int loglevel) |
| 1303 | { |
| 1304 | if (e->loglevel_type == LTTNG_UST_LOGLEVEL_ALL |
| 1305 | || e->loglevel == -1) |
| 1306 | return 1; |
| 1307 | switch (e->loglevel_type) { |
| 1308 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 1309 | switch (loglevel_type) { |
| 1310 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 1311 | if (e->loglevel >= loglevel) |
| 1312 | return 1; |
| 1313 | else |
| 1314 | return 0; |
| 1315 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 1316 | if (e->loglevel <= 0 && loglevel == 0) |
| 1317 | return 1; |
| 1318 | else |
| 1319 | return 0; |
| 1320 | } |
| 1321 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 1322 | switch (loglevel_type) { |
| 1323 | case LTTNG_UST_LOGLEVEL_RANGE: |
| 1324 | if (loglevel <= 0) |
| 1325 | return 1; |
| 1326 | else |
| 1327 | return 0; |
| 1328 | case LTTNG_UST_LOGLEVEL_SINGLE: |
| 1329 | if (e->loglevel == loglevel) |
| 1330 | return 1; |
| 1331 | else |
| 1332 | return 0; |
| 1333 | } |
| 1334 | } |
| 1335 | } |
| 1336 | #endif |
| 1337 | |
| 1338 | /* |
| 1339 | * Add the wildcard to the wildcard list. Must be called with |
| 1340 | * ust lock held. |
| 1341 | */ |
| 1342 | static |
| 1343 | struct session_wildcard *add_wildcard(struct ltt_channel *chan, |
| 1344 | struct lttng_ust_event *event_param) |
| 1345 | { |
| 1346 | struct wildcard_entry *e; |
| 1347 | struct session_wildcard *sw; |
| 1348 | size_t name_len = strlen(event_param->name) + 1; |
| 1349 | int found = 0; |
| 1350 | |
| 1351 | /* |
| 1352 | * Try to find global wildcard entry. Given that this is shared |
| 1353 | * across all sessions, we need to check for exact loglevel |
| 1354 | * match, not just whether contained within the existing ones. |
| 1355 | */ |
| 1356 | cds_list_for_each_entry(e, &wildcard_list, list) { |
| 1357 | if (!strncmp(event_param->name, e->name, |
| 1358 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
| 1359 | if (wildcard_same_loglevel(e, |
| 1360 | event_param->loglevel_type, |
| 1361 | event_param->loglevel)) { |
| 1362 | found = 1; |
| 1363 | break; |
| 1364 | } |
| 1365 | } |
| 1366 | } |
| 1367 | |
| 1368 | if (!found) { |
| 1369 | /* |
| 1370 | * Create global wildcard entry if not found. Using |
| 1371 | * zmalloc here to allocate a variable length element. |
| 1372 | * Could cause some memory fragmentation if overused. |
| 1373 | */ |
| 1374 | e = zmalloc(sizeof(struct wildcard_entry) + name_len); |
| 1375 | if (!e) |
| 1376 | return ERR_PTR(-ENOMEM); |
| 1377 | memcpy(&e->name[0], event_param->name, name_len); |
| 1378 | e->loglevel_type = event_param->loglevel_type; |
| 1379 | e->loglevel = event_param->loglevel; |
| 1380 | cds_list_add(&e->list, &wildcard_list); |
| 1381 | CDS_INIT_LIST_HEAD(&e->session_list); |
| 1382 | } |
| 1383 | |
| 1384 | /* session wildcard */ |
| 1385 | cds_list_for_each_entry(sw, &e->session_list, session_list) { |
| 1386 | if (chan == sw->chan) { |
| 1387 | DBG("wildcard %s busy for this channel", |
| 1388 | event_param->name); |
| 1389 | return ERR_PTR(-EEXIST); /* Already there */ |
| 1390 | } |
| 1391 | } |
| 1392 | sw = zmalloc(sizeof(struct session_wildcard)); |
| 1393 | if (!sw) |
| 1394 | return ERR_PTR(-ENOMEM); |
| 1395 | sw->chan = chan; |
| 1396 | sw->enabled = 1; |
| 1397 | memcpy(&sw->event_param, event_param, sizeof(sw->event_param)); |
| 1398 | sw->event_param.instrumentation = LTTNG_UST_TRACEPOINT; |
| 1399 | sw->event_param.loglevel_type = event_param->loglevel_type; |
| 1400 | sw->event_param.loglevel = event_param->loglevel; |
| 1401 | CDS_INIT_LIST_HEAD(&sw->events); |
| 1402 | cds_list_add(&sw->list, &chan->session->wildcards); |
| 1403 | cds_list_add(&sw->session_list, &e->session_list); |
| 1404 | sw->entry = e; |
| 1405 | ltt_probes_create_wildcard_events(e, sw); |
| 1406 | return sw; |
| 1407 | } |
| 1408 | |
| 1409 | /* |
| 1410 | * Remove the wildcard from the wildcard list. Must be called with |
| 1411 | * ust_lock held. Only called at session teardown. |
| 1412 | */ |
| 1413 | static |
| 1414 | void _remove_wildcard(struct session_wildcard *wildcard) |
| 1415 | { |
| 1416 | struct ltt_event *ev, *tmp; |
| 1417 | |
| 1418 | /* |
| 1419 | * Just remove the events owned (for enable/disable) by this |
| 1420 | * wildcard from the list. The session teardown will take care |
| 1421 | * of freeing the event memory. |
| 1422 | */ |
| 1423 | cds_list_for_each_entry_safe(ev, tmp, &wildcard->events, |
| 1424 | wildcard_list) { |
| 1425 | cds_list_del(&ev->wildcard_list); |
| 1426 | } |
| 1427 | cds_list_del(&wildcard->session_list); |
| 1428 | cds_list_del(&wildcard->list); |
| 1429 | if (cds_list_empty(&wildcard->entry->session_list)) { |
| 1430 | cds_list_del(&wildcard->entry->list); |
| 1431 | free(wildcard->entry); |
| 1432 | } |
| 1433 | free(wildcard->filter_bytecode); |
| 1434 | free(wildcard); |
| 1435 | } |
| 1436 | |
| 1437 | int ltt_wildcard_create(struct ltt_channel *chan, |
| 1438 | struct lttng_ust_event *event_param, |
| 1439 | struct session_wildcard **_sw) |
| 1440 | { |
| 1441 | struct session_wildcard *sw; |
| 1442 | |
| 1443 | sw = add_wildcard(chan, event_param); |
| 1444 | if (!sw || IS_ERR(sw)) { |
| 1445 | return PTR_ERR(sw); |
| 1446 | } |
| 1447 | *_sw = sw; |
| 1448 | return 0; |
| 1449 | } |
| 1450 | |
| 1451 | static |
| 1452 | void _ltt_wildcard_destroy(struct session_wildcard *sw) |
| 1453 | { |
| 1454 | _remove_wildcard(sw); |
| 1455 | } |
| 1456 | |
| 1457 | int ltt_wildcard_enable(struct session_wildcard *wildcard) |
| 1458 | { |
| 1459 | struct ltt_event *ev; |
| 1460 | int ret; |
| 1461 | |
| 1462 | if (wildcard->enabled) |
| 1463 | return -EEXIST; |
| 1464 | cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) { |
| 1465 | ret = ltt_event_enable(ev); |
| 1466 | if (ret) { |
| 1467 | DBG("Error: enable error.\n"); |
| 1468 | return ret; |
| 1469 | } |
| 1470 | } |
| 1471 | wildcard->enabled = 1; |
| 1472 | return 0; |
| 1473 | } |
| 1474 | |
| 1475 | int ltt_wildcard_disable(struct session_wildcard *wildcard) |
| 1476 | { |
| 1477 | struct ltt_event *ev; |
| 1478 | int ret; |
| 1479 | |
| 1480 | if (!wildcard->enabled) |
| 1481 | return -EEXIST; |
| 1482 | cds_list_for_each_entry(ev, &wildcard->events, wildcard_list) { |
| 1483 | ret = ltt_event_disable(ev); |
| 1484 | if (ret) { |
| 1485 | DBG("Error: disable error.\n"); |
| 1486 | return ret; |
| 1487 | } |
| 1488 | } |
| 1489 | wildcard->enabled = 0; |
| 1490 | return 0; |
| 1491 | } |
| 1492 | |
| 1493 | /* |
| 1494 | * Take the TLS "fault" in libuuid if dlopen'd, which can take the |
| 1495 | * dynamic linker mutex, outside of the UST lock, since the UST lock is |
| 1496 | * taken in constructors, which are called with dynamic linker mutex |
| 1497 | * held. |
| 1498 | */ |
| 1499 | void lttng_fixup_event_tls(void) |
| 1500 | { |
| 1501 | unsigned char uuid[LTTNG_UST_UUID_STR_LEN]; |
| 1502 | |
| 1503 | (void) lttng_ust_uuid_generate(uuid); |
| 1504 | } |