| 1 | /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1) |
| 2 | * |
| 3 | * lttng-events.c |
| 4 | * |
| 5 | * Holds LTTng per-session event registry. |
| 6 | * |
| 7 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 8 | */ |
| 9 | |
| 10 | /* |
| 11 | * This page_alloc.h wrapper needs to be included before gfpflags.h because it |
| 12 | * overrides a function with a define. |
| 13 | */ |
| 14 | #include "wrapper/page_alloc.h" |
| 15 | |
| 16 | #include <linux/module.h> |
| 17 | #include <linux/mutex.h> |
| 18 | #include <linux/sched.h> |
| 19 | #include <linux/slab.h> |
| 20 | #include <linux/jiffies.h> |
| 21 | #include <linux/utsname.h> |
| 22 | #include <linux/err.h> |
| 23 | #include <linux/seq_file.h> |
| 24 | #include <linux/file.h> |
| 25 | #include <linux/anon_inodes.h> |
| 26 | #include <wrapper/file.h> |
| 27 | #include <linux/jhash.h> |
| 28 | #include <linux/uaccess.h> |
| 29 | #include <linux/vmalloc.h> |
| 30 | #include <linux/uuid.h> |
| 31 | #include <linux/dmi.h> |
| 32 | |
| 33 | #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_all() */ |
| 34 | #include <wrapper/random.h> |
| 35 | #include <wrapper/tracepoint.h> |
| 36 | #include <wrapper/list.h> |
| 37 | #include <wrapper/types.h> |
| 38 | #include <lttng-kernel-version.h> |
| 39 | #include <lttng-events.h> |
| 40 | #include <lttng-tracer.h> |
| 41 | #include <lttng-abi-old.h> |
| 42 | #include <lttng-endian.h> |
| 43 | #include <lttng-string-utils.h> |
| 44 | #include <wrapper/ringbuffer/backend.h> |
| 45 | #include <wrapper/ringbuffer/frontend.h> |
| 46 | #include <wrapper/time.h> |
| 47 | |
| 48 | #define METADATA_CACHE_DEFAULT_SIZE 4096 |
| 49 | |
| 50 | static LIST_HEAD(sessions); |
| 51 | static LIST_HEAD(lttng_transport_list); |
| 52 | /* |
| 53 | * Protect the sessions and metadata caches. |
| 54 | */ |
| 55 | static DEFINE_MUTEX(sessions_mutex); |
| 56 | static struct kmem_cache *event_cache; |
| 57 | |
| 58 | static void lttng_session_lazy_sync_enablers(struct lttng_session *session); |
| 59 | static void lttng_session_sync_enablers(struct lttng_session *session); |
| 60 | static void lttng_enabler_destroy(struct lttng_enabler *enabler); |
| 61 | |
| 62 | static void _lttng_event_destroy(struct lttng_event *event); |
| 63 | static void _lttng_channel_destroy(struct lttng_channel *chan); |
| 64 | static int _lttng_event_unregister(struct lttng_event *event); |
| 65 | static |
| 66 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
| 67 | struct lttng_channel *chan, |
| 68 | struct lttng_event *event); |
| 69 | static |
| 70 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
| 71 | static |
| 72 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream); |
| 73 | static |
| 74 | int _lttng_field_statedump(struct lttng_session *session, |
| 75 | const struct lttng_event_field *field, |
| 76 | size_t nesting); |
| 77 | |
| 78 | void synchronize_trace(void) |
| 79 | { |
| 80 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,1,0)) |
| 81 | synchronize_rcu(); |
| 82 | #else |
| 83 | synchronize_sched(); |
| 84 | #endif |
| 85 | |
| 86 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
| 87 | #ifdef CONFIG_PREEMPT_RT_FULL |
| 88 | synchronize_rcu(); |
| 89 | #endif |
| 90 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
| 91 | #ifdef CONFIG_PREEMPT_RT |
| 92 | synchronize_rcu(); |
| 93 | #endif |
| 94 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
| 95 | } |
| 96 | |
| 97 | void lttng_lock_sessions(void) |
| 98 | { |
| 99 | mutex_lock(&sessions_mutex); |
| 100 | } |
| 101 | |
| 102 | void lttng_unlock_sessions(void) |
| 103 | { |
| 104 | mutex_unlock(&sessions_mutex); |
| 105 | } |
| 106 | |
| 107 | /* |
| 108 | * Called with sessions lock held. |
| 109 | */ |
| 110 | int lttng_session_active(void) |
| 111 | { |
| 112 | struct lttng_session *iter; |
| 113 | |
| 114 | list_for_each_entry(iter, &sessions, list) { |
| 115 | if (iter->active) |
| 116 | return 1; |
| 117 | } |
| 118 | return 0; |
| 119 | } |
| 120 | |
| 121 | struct lttng_session *lttng_session_create(void) |
| 122 | { |
| 123 | struct lttng_session *session; |
| 124 | struct lttng_metadata_cache *metadata_cache; |
| 125 | int i; |
| 126 | |
| 127 | mutex_lock(&sessions_mutex); |
| 128 | session = lttng_kvzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
| 129 | if (!session) |
| 130 | goto err; |
| 131 | INIT_LIST_HEAD(&session->chan); |
| 132 | INIT_LIST_HEAD(&session->events); |
| 133 | uuid_le_gen(&session->uuid); |
| 134 | |
| 135 | metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache), |
| 136 | GFP_KERNEL); |
| 137 | if (!metadata_cache) |
| 138 | goto err_free_session; |
| 139 | metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE); |
| 140 | if (!metadata_cache->data) |
| 141 | goto err_free_cache; |
| 142 | metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE; |
| 143 | kref_init(&metadata_cache->refcount); |
| 144 | mutex_init(&metadata_cache->lock); |
| 145 | session->metadata_cache = metadata_cache; |
| 146 | INIT_LIST_HEAD(&metadata_cache->metadata_stream); |
| 147 | memcpy(&metadata_cache->uuid, &session->uuid, |
| 148 | sizeof(metadata_cache->uuid)); |
| 149 | INIT_LIST_HEAD(&session->enablers_head); |
| 150 | for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++) |
| 151 | INIT_HLIST_HEAD(&session->events_ht.table[i]); |
| 152 | list_add(&session->list, &sessions); |
| 153 | session->pid_tracker.session = session; |
| 154 | session->pid_tracker.tracker_type = TRACKER_PID; |
| 155 | session->vpid_tracker.session = session; |
| 156 | session->vpid_tracker.tracker_type = TRACKER_VPID; |
| 157 | session->uid_tracker.session = session; |
| 158 | session->uid_tracker.tracker_type = TRACKER_UID; |
| 159 | session->vuid_tracker.session = session; |
| 160 | session->vuid_tracker.tracker_type = TRACKER_VUID; |
| 161 | session->gid_tracker.session = session; |
| 162 | session->gid_tracker.tracker_type = TRACKER_GID; |
| 163 | session->vgid_tracker.session = session; |
| 164 | session->vgid_tracker.tracker_type = TRACKER_VGID; |
| 165 | mutex_unlock(&sessions_mutex); |
| 166 | return session; |
| 167 | |
| 168 | err_free_cache: |
| 169 | kfree(metadata_cache); |
| 170 | err_free_session: |
| 171 | lttng_kvfree(session); |
| 172 | err: |
| 173 | mutex_unlock(&sessions_mutex); |
| 174 | return NULL; |
| 175 | } |
| 176 | |
| 177 | void metadata_cache_destroy(struct kref *kref) |
| 178 | { |
| 179 | struct lttng_metadata_cache *cache = |
| 180 | container_of(kref, struct lttng_metadata_cache, refcount); |
| 181 | vfree(cache->data); |
| 182 | kfree(cache); |
| 183 | } |
| 184 | |
| 185 | void lttng_session_destroy(struct lttng_session *session) |
| 186 | { |
| 187 | struct lttng_channel *chan, *tmpchan; |
| 188 | struct lttng_event *event, *tmpevent; |
| 189 | struct lttng_metadata_stream *metadata_stream; |
| 190 | struct lttng_enabler *enabler, *tmpenabler; |
| 191 | int ret; |
| 192 | |
| 193 | mutex_lock(&sessions_mutex); |
| 194 | WRITE_ONCE(session->active, 0); |
| 195 | list_for_each_entry(chan, &session->chan, list) { |
| 196 | ret = lttng_syscalls_unregister(chan); |
| 197 | WARN_ON(ret); |
| 198 | } |
| 199 | list_for_each_entry(event, &session->events, list) { |
| 200 | ret = _lttng_event_unregister(event); |
| 201 | WARN_ON(ret); |
| 202 | } |
| 203 | synchronize_trace(); /* Wait for in-flight events to complete */ |
| 204 | list_for_each_entry_safe(enabler, tmpenabler, |
| 205 | &session->enablers_head, node) |
| 206 | lttng_enabler_destroy(enabler); |
| 207 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
| 208 | _lttng_event_destroy(event); |
| 209 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { |
| 210 | BUG_ON(chan->channel_type == METADATA_CHANNEL); |
| 211 | _lttng_channel_destroy(chan); |
| 212 | } |
| 213 | list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) |
| 214 | _lttng_metadata_channel_hangup(metadata_stream); |
| 215 | lttng_id_tracker_destroy(&session->pid_tracker, false); |
| 216 | lttng_id_tracker_destroy(&session->vpid_tracker, false); |
| 217 | lttng_id_tracker_destroy(&session->uid_tracker, false); |
| 218 | lttng_id_tracker_destroy(&session->vuid_tracker, false); |
| 219 | lttng_id_tracker_destroy(&session->gid_tracker, false); |
| 220 | lttng_id_tracker_destroy(&session->vgid_tracker, false); |
| 221 | kref_put(&session->metadata_cache->refcount, metadata_cache_destroy); |
| 222 | list_del(&session->list); |
| 223 | mutex_unlock(&sessions_mutex); |
| 224 | lttng_kvfree(session); |
| 225 | } |
| 226 | |
| 227 | int lttng_session_statedump(struct lttng_session *session) |
| 228 | { |
| 229 | int ret; |
| 230 | |
| 231 | mutex_lock(&sessions_mutex); |
| 232 | ret = lttng_statedump_start(session); |
| 233 | mutex_unlock(&sessions_mutex); |
| 234 | return ret; |
| 235 | } |
| 236 | |
| 237 | int lttng_session_enable(struct lttng_session *session) |
| 238 | { |
| 239 | int ret = 0; |
| 240 | struct lttng_channel *chan; |
| 241 | |
| 242 | mutex_lock(&sessions_mutex); |
| 243 | if (session->active) { |
| 244 | ret = -EBUSY; |
| 245 | goto end; |
| 246 | } |
| 247 | |
| 248 | /* Set transient enabler state to "enabled" */ |
| 249 | session->tstate = 1; |
| 250 | |
| 251 | /* We need to sync enablers with session before activation. */ |
| 252 | lttng_session_sync_enablers(session); |
| 253 | |
| 254 | /* |
| 255 | * Snapshot the number of events per channel to know the type of header |
| 256 | * we need to use. |
| 257 | */ |
| 258 | list_for_each_entry(chan, &session->chan, list) { |
| 259 | if (chan->header_type) |
| 260 | continue; /* don't change it if session stop/restart */ |
| 261 | if (chan->free_event_id < 31) |
| 262 | chan->header_type = 1; /* compact */ |
| 263 | else |
| 264 | chan->header_type = 2; /* large */ |
| 265 | } |
| 266 | |
| 267 | /* Clear each stream's quiescent state. */ |
| 268 | list_for_each_entry(chan, &session->chan, list) { |
| 269 | if (chan->channel_type != METADATA_CHANNEL) |
| 270 | lib_ring_buffer_clear_quiescent_channel(chan->chan); |
| 271 | } |
| 272 | |
| 273 | WRITE_ONCE(session->active, 1); |
| 274 | WRITE_ONCE(session->been_active, 1); |
| 275 | ret = _lttng_session_metadata_statedump(session); |
| 276 | if (ret) { |
| 277 | WRITE_ONCE(session->active, 0); |
| 278 | goto end; |
| 279 | } |
| 280 | ret = lttng_statedump_start(session); |
| 281 | if (ret) |
| 282 | WRITE_ONCE(session->active, 0); |
| 283 | end: |
| 284 | mutex_unlock(&sessions_mutex); |
| 285 | return ret; |
| 286 | } |
| 287 | |
| 288 | int lttng_session_disable(struct lttng_session *session) |
| 289 | { |
| 290 | int ret = 0; |
| 291 | struct lttng_channel *chan; |
| 292 | |
| 293 | mutex_lock(&sessions_mutex); |
| 294 | if (!session->active) { |
| 295 | ret = -EBUSY; |
| 296 | goto end; |
| 297 | } |
| 298 | WRITE_ONCE(session->active, 0); |
| 299 | |
| 300 | /* Set transient enabler state to "disabled" */ |
| 301 | session->tstate = 0; |
| 302 | lttng_session_sync_enablers(session); |
| 303 | |
| 304 | /* Set each stream's quiescent state. */ |
| 305 | list_for_each_entry(chan, &session->chan, list) { |
| 306 | if (chan->channel_type != METADATA_CHANNEL) |
| 307 | lib_ring_buffer_set_quiescent_channel(chan->chan); |
| 308 | } |
| 309 | end: |
| 310 | mutex_unlock(&sessions_mutex); |
| 311 | return ret; |
| 312 | } |
| 313 | |
| 314 | int lttng_session_metadata_regenerate(struct lttng_session *session) |
| 315 | { |
| 316 | int ret = 0; |
| 317 | struct lttng_channel *chan; |
| 318 | struct lttng_event *event; |
| 319 | struct lttng_metadata_cache *cache = session->metadata_cache; |
| 320 | struct lttng_metadata_stream *stream; |
| 321 | |
| 322 | mutex_lock(&sessions_mutex); |
| 323 | if (!session->active) { |
| 324 | ret = -EBUSY; |
| 325 | goto end; |
| 326 | } |
| 327 | |
| 328 | mutex_lock(&cache->lock); |
| 329 | memset(cache->data, 0, cache->cache_alloc); |
| 330 | cache->metadata_written = 0; |
| 331 | cache->version++; |
| 332 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) { |
| 333 | stream->metadata_out = 0; |
| 334 | stream->metadata_in = 0; |
| 335 | } |
| 336 | mutex_unlock(&cache->lock); |
| 337 | |
| 338 | session->metadata_dumped = 0; |
| 339 | list_for_each_entry(chan, &session->chan, list) { |
| 340 | chan->metadata_dumped = 0; |
| 341 | } |
| 342 | |
| 343 | list_for_each_entry(event, &session->events, list) { |
| 344 | event->metadata_dumped = 0; |
| 345 | } |
| 346 | |
| 347 | ret = _lttng_session_metadata_statedump(session); |
| 348 | |
| 349 | end: |
| 350 | mutex_unlock(&sessions_mutex); |
| 351 | return ret; |
| 352 | } |
| 353 | |
| 354 | int lttng_channel_enable(struct lttng_channel *channel) |
| 355 | { |
| 356 | int ret = 0; |
| 357 | |
| 358 | mutex_lock(&sessions_mutex); |
| 359 | if (channel->channel_type == METADATA_CHANNEL) { |
| 360 | ret = -EPERM; |
| 361 | goto end; |
| 362 | } |
| 363 | if (channel->enabled) { |
| 364 | ret = -EEXIST; |
| 365 | goto end; |
| 366 | } |
| 367 | /* Set transient enabler state to "enabled" */ |
| 368 | channel->tstate = 1; |
| 369 | lttng_session_sync_enablers(channel->session); |
| 370 | /* Set atomically the state to "enabled" */ |
| 371 | WRITE_ONCE(channel->enabled, 1); |
| 372 | end: |
| 373 | mutex_unlock(&sessions_mutex); |
| 374 | return ret; |
| 375 | } |
| 376 | |
| 377 | int lttng_channel_disable(struct lttng_channel *channel) |
| 378 | { |
| 379 | int ret = 0; |
| 380 | |
| 381 | mutex_lock(&sessions_mutex); |
| 382 | if (channel->channel_type == METADATA_CHANNEL) { |
| 383 | ret = -EPERM; |
| 384 | goto end; |
| 385 | } |
| 386 | if (!channel->enabled) { |
| 387 | ret = -EEXIST; |
| 388 | goto end; |
| 389 | } |
| 390 | /* Set atomically the state to "disabled" */ |
| 391 | WRITE_ONCE(channel->enabled, 0); |
| 392 | /* Set transient enabler state to "enabled" */ |
| 393 | channel->tstate = 0; |
| 394 | lttng_session_sync_enablers(channel->session); |
| 395 | end: |
| 396 | mutex_unlock(&sessions_mutex); |
| 397 | return ret; |
| 398 | } |
| 399 | |
| 400 | int lttng_event_enable(struct lttng_event *event) |
| 401 | { |
| 402 | int ret = 0; |
| 403 | |
| 404 | mutex_lock(&sessions_mutex); |
| 405 | if (event->chan->channel_type == METADATA_CHANNEL) { |
| 406 | ret = -EPERM; |
| 407 | goto end; |
| 408 | } |
| 409 | if (event->enabled) { |
| 410 | ret = -EEXIST; |
| 411 | goto end; |
| 412 | } |
| 413 | switch (event->instrumentation) { |
| 414 | case LTTNG_KERNEL_TRACEPOINT: |
| 415 | case LTTNG_KERNEL_SYSCALL: |
| 416 | ret = -EINVAL; |
| 417 | break; |
| 418 | case LTTNG_KERNEL_KPROBE: |
| 419 | case LTTNG_KERNEL_FUNCTION: |
| 420 | case LTTNG_KERNEL_UPROBE: |
| 421 | case LTTNG_KERNEL_NOOP: |
| 422 | WRITE_ONCE(event->enabled, 1); |
| 423 | break; |
| 424 | case LTTNG_KERNEL_KRETPROBE: |
| 425 | ret = lttng_kretprobes_event_enable_state(event, 1); |
| 426 | break; |
| 427 | default: |
| 428 | WARN_ON_ONCE(1); |
| 429 | ret = -EINVAL; |
| 430 | } |
| 431 | end: |
| 432 | mutex_unlock(&sessions_mutex); |
| 433 | return ret; |
| 434 | } |
| 435 | |
| 436 | int lttng_event_disable(struct lttng_event *event) |
| 437 | { |
| 438 | int ret = 0; |
| 439 | |
| 440 | mutex_lock(&sessions_mutex); |
| 441 | if (event->chan->channel_type == METADATA_CHANNEL) { |
| 442 | ret = -EPERM; |
| 443 | goto end; |
| 444 | } |
| 445 | if (!event->enabled) { |
| 446 | ret = -EEXIST; |
| 447 | goto end; |
| 448 | } |
| 449 | switch (event->instrumentation) { |
| 450 | case LTTNG_KERNEL_TRACEPOINT: |
| 451 | case LTTNG_KERNEL_SYSCALL: |
| 452 | ret = -EINVAL; |
| 453 | break; |
| 454 | case LTTNG_KERNEL_KPROBE: |
| 455 | case LTTNG_KERNEL_FUNCTION: |
| 456 | case LTTNG_KERNEL_UPROBE: |
| 457 | case LTTNG_KERNEL_NOOP: |
| 458 | WRITE_ONCE(event->enabled, 0); |
| 459 | break; |
| 460 | case LTTNG_KERNEL_KRETPROBE: |
| 461 | ret = lttng_kretprobes_event_enable_state(event, 0); |
| 462 | break; |
| 463 | default: |
| 464 | WARN_ON_ONCE(1); |
| 465 | ret = -EINVAL; |
| 466 | } |
| 467 | end: |
| 468 | mutex_unlock(&sessions_mutex); |
| 469 | return ret; |
| 470 | } |
| 471 | |
| 472 | static struct lttng_transport *lttng_transport_find(const char *name) |
| 473 | { |
| 474 | struct lttng_transport *transport; |
| 475 | |
| 476 | list_for_each_entry(transport, <tng_transport_list, node) { |
| 477 | if (!strcmp(transport->name, name)) |
| 478 | return transport; |
| 479 | } |
| 480 | return NULL; |
| 481 | } |
| 482 | |
| 483 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
| 484 | const char *transport_name, |
| 485 | void *buf_addr, |
| 486 | size_t subbuf_size, size_t num_subbuf, |
| 487 | unsigned int switch_timer_interval, |
| 488 | unsigned int read_timer_interval, |
| 489 | enum channel_type channel_type) |
| 490 | { |
| 491 | struct lttng_channel *chan; |
| 492 | struct lttng_transport *transport = NULL; |
| 493 | |
| 494 | mutex_lock(&sessions_mutex); |
| 495 | if (session->been_active && channel_type != METADATA_CHANNEL) |
| 496 | goto active; /* Refuse to add channel to active session */ |
| 497 | transport = lttng_transport_find(transport_name); |
| 498 | if (!transport) { |
| 499 | printk(KERN_WARNING "LTTng transport %s not found\n", |
| 500 | transport_name); |
| 501 | goto notransport; |
| 502 | } |
| 503 | if (!try_module_get(transport->owner)) { |
| 504 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); |
| 505 | goto notransport; |
| 506 | } |
| 507 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
| 508 | if (!chan) |
| 509 | goto nomem; |
| 510 | chan->session = session; |
| 511 | chan->id = session->free_chan_id++; |
| 512 | chan->ops = &transport->ops; |
| 513 | /* |
| 514 | * Note: the channel creation op already writes into the packet |
| 515 | * headers. Therefore the "chan" information used as input |
| 516 | * should be already accessible. |
| 517 | */ |
| 518 | chan->chan = transport->ops.channel_create(transport_name, |
| 519 | chan, buf_addr, subbuf_size, num_subbuf, |
| 520 | switch_timer_interval, read_timer_interval); |
| 521 | if (!chan->chan) |
| 522 | goto create_error; |
| 523 | chan->tstate = 1; |
| 524 | chan->enabled = 1; |
| 525 | chan->transport = transport; |
| 526 | chan->channel_type = channel_type; |
| 527 | list_add(&chan->list, &session->chan); |
| 528 | mutex_unlock(&sessions_mutex); |
| 529 | return chan; |
| 530 | |
| 531 | create_error: |
| 532 | kfree(chan); |
| 533 | nomem: |
| 534 | if (transport) |
| 535 | module_put(transport->owner); |
| 536 | notransport: |
| 537 | active: |
| 538 | mutex_unlock(&sessions_mutex); |
| 539 | return NULL; |
| 540 | } |
| 541 | |
| 542 | /* |
| 543 | * Only used internally at session destruction for per-cpu channels, and |
| 544 | * when metadata channel is released. |
| 545 | * Needs to be called with sessions mutex held. |
| 546 | */ |
| 547 | static |
| 548 | void _lttng_channel_destroy(struct lttng_channel *chan) |
| 549 | { |
| 550 | chan->ops->channel_destroy(chan->chan); |
| 551 | module_put(chan->transport->owner); |
| 552 | list_del(&chan->list); |
| 553 | lttng_destroy_context(chan->ctx); |
| 554 | kfree(chan); |
| 555 | } |
| 556 | |
| 557 | void lttng_metadata_channel_destroy(struct lttng_channel *chan) |
| 558 | { |
| 559 | BUG_ON(chan->channel_type != METADATA_CHANNEL); |
| 560 | |
| 561 | /* Protect the metadata cache with the sessions_mutex. */ |
| 562 | mutex_lock(&sessions_mutex); |
| 563 | _lttng_channel_destroy(chan); |
| 564 | mutex_unlock(&sessions_mutex); |
| 565 | } |
| 566 | EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy); |
| 567 | |
| 568 | static |
| 569 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream) |
| 570 | { |
| 571 | stream->finalized = 1; |
| 572 | wake_up_interruptible(&stream->read_wait); |
| 573 | } |
| 574 | |
| 575 | /* |
| 576 | * Supports event creation while tracing session is active. |
| 577 | * Needs to be called with sessions mutex held. |
| 578 | */ |
| 579 | struct lttng_event *_lttng_event_create(struct lttng_channel *chan, |
| 580 | struct lttng_kernel_event *event_param, |
| 581 | void *filter, |
| 582 | const struct lttng_event_desc *event_desc, |
| 583 | enum lttng_kernel_instrumentation itype) |
| 584 | { |
| 585 | struct lttng_session *session = chan->session; |
| 586 | struct lttng_event *event; |
| 587 | const char *event_name; |
| 588 | struct hlist_head *head; |
| 589 | size_t name_len; |
| 590 | uint32_t hash; |
| 591 | int ret; |
| 592 | |
| 593 | if (chan->free_event_id == -1U) { |
| 594 | ret = -EMFILE; |
| 595 | goto full; |
| 596 | } |
| 597 | |
| 598 | switch (itype) { |
| 599 | case LTTNG_KERNEL_TRACEPOINT: |
| 600 | event_name = event_desc->name; |
| 601 | break; |
| 602 | case LTTNG_KERNEL_KPROBE: |
| 603 | case LTTNG_KERNEL_UPROBE: |
| 604 | case LTTNG_KERNEL_KRETPROBE: |
| 605 | case LTTNG_KERNEL_FUNCTION: |
| 606 | case LTTNG_KERNEL_NOOP: |
| 607 | case LTTNG_KERNEL_SYSCALL: |
| 608 | event_name = event_param->name; |
| 609 | break; |
| 610 | default: |
| 611 | WARN_ON_ONCE(1); |
| 612 | ret = -EINVAL; |
| 613 | goto type_error; |
| 614 | } |
| 615 | name_len = strlen(event_name); |
| 616 | hash = jhash(event_name, name_len, 0); |
| 617 | head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; |
| 618 | lttng_hlist_for_each_entry(event, head, hlist) { |
| 619 | WARN_ON_ONCE(!event->desc); |
| 620 | if (!strncmp(event->desc->name, event_name, |
| 621 | LTTNG_KERNEL_SYM_NAME_LEN - 1) |
| 622 | && chan == event->chan) { |
| 623 | ret = -EEXIST; |
| 624 | goto exist; |
| 625 | } |
| 626 | } |
| 627 | |
| 628 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
| 629 | if (!event) { |
| 630 | ret = -ENOMEM; |
| 631 | goto cache_error; |
| 632 | } |
| 633 | event->chan = chan; |
| 634 | event->filter = filter; |
| 635 | event->id = chan->free_event_id++; |
| 636 | event->instrumentation = itype; |
| 637 | event->evtype = LTTNG_TYPE_EVENT; |
| 638 | INIT_LIST_HEAD(&event->bytecode_runtime_head); |
| 639 | INIT_LIST_HEAD(&event->enablers_ref_head); |
| 640 | |
| 641 | switch (itype) { |
| 642 | case LTTNG_KERNEL_TRACEPOINT: |
| 643 | /* Event will be enabled by enabler sync. */ |
| 644 | event->enabled = 0; |
| 645 | event->registered = 0; |
| 646 | event->desc = lttng_event_get(event_name); |
| 647 | if (!event->desc) { |
| 648 | ret = -ENOENT; |
| 649 | goto register_error; |
| 650 | } |
| 651 | /* Populate lttng_event structure before event registration. */ |
| 652 | smp_wmb(); |
| 653 | break; |
| 654 | case LTTNG_KERNEL_KPROBE: |
| 655 | /* |
| 656 | * Needs to be explicitly enabled after creation, since |
| 657 | * we may want to apply filters. |
| 658 | */ |
| 659 | event->enabled = 0; |
| 660 | event->registered = 1; |
| 661 | /* |
| 662 | * Populate lttng_event structure before event |
| 663 | * registration. |
| 664 | */ |
| 665 | smp_wmb(); |
| 666 | ret = lttng_kprobes_register(event_name, |
| 667 | event_param->u.kprobe.symbol_name, |
| 668 | event_param->u.kprobe.offset, |
| 669 | event_param->u.kprobe.addr, |
| 670 | event); |
| 671 | if (ret) { |
| 672 | ret = -EINVAL; |
| 673 | goto register_error; |
| 674 | } |
| 675 | ret = try_module_get(event->desc->owner); |
| 676 | WARN_ON_ONCE(!ret); |
| 677 | break; |
| 678 | case LTTNG_KERNEL_KRETPROBE: |
| 679 | { |
| 680 | struct lttng_event *event_return; |
| 681 | |
| 682 | /* kretprobe defines 2 events */ |
| 683 | /* |
| 684 | * Needs to be explicitly enabled after creation, since |
| 685 | * we may want to apply filters. |
| 686 | */ |
| 687 | event->enabled = 0; |
| 688 | event->registered = 1; |
| 689 | event_return = |
| 690 | kmem_cache_zalloc(event_cache, GFP_KERNEL); |
| 691 | if (!event_return) { |
| 692 | ret = -ENOMEM; |
| 693 | goto register_error; |
| 694 | } |
| 695 | event_return->chan = chan; |
| 696 | event_return->filter = filter; |
| 697 | event_return->id = chan->free_event_id++; |
| 698 | event_return->enabled = 0; |
| 699 | event_return->registered = 1; |
| 700 | event_return->instrumentation = itype; |
| 701 | /* |
| 702 | * Populate lttng_event structure before kretprobe registration. |
| 703 | */ |
| 704 | smp_wmb(); |
| 705 | ret = lttng_kretprobes_register(event_name, |
| 706 | event_param->u.kretprobe.symbol_name, |
| 707 | event_param->u.kretprobe.offset, |
| 708 | event_param->u.kretprobe.addr, |
| 709 | event, event_return); |
| 710 | if (ret) { |
| 711 | kmem_cache_free(event_cache, event_return); |
| 712 | ret = -EINVAL; |
| 713 | goto register_error; |
| 714 | } |
| 715 | /* Take 2 refs on the module: one per event. */ |
| 716 | ret = try_module_get(event->desc->owner); |
| 717 | WARN_ON_ONCE(!ret); |
| 718 | ret = try_module_get(event->desc->owner); |
| 719 | WARN_ON_ONCE(!ret); |
| 720 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
| 721 | event_return); |
| 722 | WARN_ON_ONCE(ret > 0); |
| 723 | if (ret) { |
| 724 | kmem_cache_free(event_cache, event_return); |
| 725 | module_put(event->desc->owner); |
| 726 | module_put(event->desc->owner); |
| 727 | goto statedump_error; |
| 728 | } |
| 729 | list_add(&event_return->list, &chan->session->events); |
| 730 | break; |
| 731 | } |
| 732 | case LTTNG_KERNEL_FUNCTION: |
| 733 | /* |
| 734 | * Needs to be explicitly enabled after creation, since |
| 735 | * we may want to apply filters. |
| 736 | */ |
| 737 | event->enabled = 0; |
| 738 | event->registered = 1; |
| 739 | /* |
| 740 | * Populate lttng_event structure before event |
| 741 | * registration. |
| 742 | */ |
| 743 | smp_wmb(); |
| 744 | ret = lttng_ftrace_register(event_name, |
| 745 | event_param->u.ftrace.symbol_name, |
| 746 | event); |
| 747 | if (ret) { |
| 748 | goto register_error; |
| 749 | } |
| 750 | ret = try_module_get(event->desc->owner); |
| 751 | WARN_ON_ONCE(!ret); |
| 752 | break; |
| 753 | case LTTNG_KERNEL_NOOP: |
| 754 | case LTTNG_KERNEL_SYSCALL: |
| 755 | /* |
| 756 | * Needs to be explicitly enabled after creation, since |
| 757 | * we may want to apply filters. |
| 758 | */ |
| 759 | event->enabled = 0; |
| 760 | event->registered = 0; |
| 761 | event->desc = event_desc; |
| 762 | if (!event->desc) { |
| 763 | ret = -EINVAL; |
| 764 | goto register_error; |
| 765 | } |
| 766 | break; |
| 767 | case LTTNG_KERNEL_UPROBE: |
| 768 | /* |
| 769 | * Needs to be explicitly enabled after creation, since |
| 770 | * we may want to apply filters. |
| 771 | */ |
| 772 | event->enabled = 0; |
| 773 | event->registered = 1; |
| 774 | |
| 775 | /* |
| 776 | * Populate lttng_event structure before event |
| 777 | * registration. |
| 778 | */ |
| 779 | smp_wmb(); |
| 780 | |
| 781 | ret = lttng_uprobes_register(event_param->name, |
| 782 | event_param->u.uprobe.fd, |
| 783 | event); |
| 784 | if (ret) |
| 785 | goto register_error; |
| 786 | ret = try_module_get(event->desc->owner); |
| 787 | WARN_ON_ONCE(!ret); |
| 788 | break; |
| 789 | default: |
| 790 | WARN_ON_ONCE(1); |
| 791 | ret = -EINVAL; |
| 792 | goto register_error; |
| 793 | } |
| 794 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
| 795 | WARN_ON_ONCE(ret > 0); |
| 796 | if (ret) { |
| 797 | goto statedump_error; |
| 798 | } |
| 799 | hlist_add_head(&event->hlist, head); |
| 800 | list_add(&event->list, &chan->session->events); |
| 801 | return event; |
| 802 | |
| 803 | statedump_error: |
| 804 | /* If a statedump error occurs, events will not be readable. */ |
| 805 | register_error: |
| 806 | kmem_cache_free(event_cache, event); |
| 807 | cache_error: |
| 808 | exist: |
| 809 | type_error: |
| 810 | full: |
| 811 | return ERR_PTR(ret); |
| 812 | } |
| 813 | |
| 814 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
| 815 | struct lttng_kernel_event *event_param, |
| 816 | void *filter, |
| 817 | const struct lttng_event_desc *event_desc, |
| 818 | enum lttng_kernel_instrumentation itype) |
| 819 | { |
| 820 | struct lttng_event *event; |
| 821 | |
| 822 | mutex_lock(&sessions_mutex); |
| 823 | event = _lttng_event_create(chan, event_param, filter, event_desc, |
| 824 | itype); |
| 825 | mutex_unlock(&sessions_mutex); |
| 826 | return event; |
| 827 | } |
| 828 | |
| 829 | /* Only used for tracepoints for now. */ |
| 830 | static |
| 831 | void register_event(struct lttng_event *event) |
| 832 | { |
| 833 | const struct lttng_event_desc *desc; |
| 834 | int ret = -EINVAL; |
| 835 | |
| 836 | if (event->registered) |
| 837 | return; |
| 838 | |
| 839 | desc = event->desc; |
| 840 | switch (event->instrumentation) { |
| 841 | case LTTNG_KERNEL_TRACEPOINT: |
| 842 | ret = lttng_wrapper_tracepoint_probe_register(desc->kname, |
| 843 | desc->probe_callback, |
| 844 | event); |
| 845 | break; |
| 846 | case LTTNG_KERNEL_SYSCALL: |
| 847 | ret = lttng_syscall_filter_enable(event->chan, |
| 848 | desc->name); |
| 849 | break; |
| 850 | case LTTNG_KERNEL_KPROBE: |
| 851 | case LTTNG_KERNEL_UPROBE: |
| 852 | case LTTNG_KERNEL_KRETPROBE: |
| 853 | case LTTNG_KERNEL_FUNCTION: |
| 854 | case LTTNG_KERNEL_NOOP: |
| 855 | ret = 0; |
| 856 | break; |
| 857 | default: |
| 858 | WARN_ON_ONCE(1); |
| 859 | } |
| 860 | if (!ret) |
| 861 | event->registered = 1; |
| 862 | } |
| 863 | |
| 864 | /* |
| 865 | * Only used internally at session destruction. |
| 866 | */ |
| 867 | int _lttng_event_unregister(struct lttng_event *event) |
| 868 | { |
| 869 | const struct lttng_event_desc *desc; |
| 870 | int ret = -EINVAL; |
| 871 | |
| 872 | if (!event->registered) |
| 873 | return 0; |
| 874 | |
| 875 | desc = event->desc; |
| 876 | switch (event->instrumentation) { |
| 877 | case LTTNG_KERNEL_TRACEPOINT: |
| 878 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
| 879 | event->desc->probe_callback, |
| 880 | event); |
| 881 | break; |
| 882 | case LTTNG_KERNEL_KPROBE: |
| 883 | lttng_kprobes_unregister(event); |
| 884 | ret = 0; |
| 885 | break; |
| 886 | case LTTNG_KERNEL_KRETPROBE: |
| 887 | lttng_kretprobes_unregister(event); |
| 888 | ret = 0; |
| 889 | break; |
| 890 | case LTTNG_KERNEL_FUNCTION: |
| 891 | lttng_ftrace_unregister(event); |
| 892 | ret = 0; |
| 893 | break; |
| 894 | case LTTNG_KERNEL_SYSCALL: |
| 895 | ret = lttng_syscall_filter_disable(event->chan, |
| 896 | desc->name); |
| 897 | break; |
| 898 | case LTTNG_KERNEL_NOOP: |
| 899 | ret = 0; |
| 900 | break; |
| 901 | case LTTNG_KERNEL_UPROBE: |
| 902 | lttng_uprobes_unregister(event); |
| 903 | ret = 0; |
| 904 | break; |
| 905 | default: |
| 906 | WARN_ON_ONCE(1); |
| 907 | } |
| 908 | if (!ret) |
| 909 | event->registered = 0; |
| 910 | return ret; |
| 911 | } |
| 912 | |
| 913 | /* |
| 914 | * Only used internally at session destruction. |
| 915 | */ |
| 916 | static |
| 917 | void _lttng_event_destroy(struct lttng_event *event) |
| 918 | { |
| 919 | switch (event->instrumentation) { |
| 920 | case LTTNG_KERNEL_TRACEPOINT: |
| 921 | lttng_event_put(event->desc); |
| 922 | break; |
| 923 | case LTTNG_KERNEL_KPROBE: |
| 924 | module_put(event->desc->owner); |
| 925 | lttng_kprobes_destroy_private(event); |
| 926 | break; |
| 927 | case LTTNG_KERNEL_KRETPROBE: |
| 928 | module_put(event->desc->owner); |
| 929 | lttng_kretprobes_destroy_private(event); |
| 930 | break; |
| 931 | case LTTNG_KERNEL_FUNCTION: |
| 932 | module_put(event->desc->owner); |
| 933 | lttng_ftrace_destroy_private(event); |
| 934 | break; |
| 935 | case LTTNG_KERNEL_NOOP: |
| 936 | case LTTNG_KERNEL_SYSCALL: |
| 937 | break; |
| 938 | case LTTNG_KERNEL_UPROBE: |
| 939 | module_put(event->desc->owner); |
| 940 | lttng_uprobes_destroy_private(event); |
| 941 | break; |
| 942 | default: |
| 943 | WARN_ON_ONCE(1); |
| 944 | } |
| 945 | list_del(&event->list); |
| 946 | lttng_destroy_context(event->ctx); |
| 947 | kmem_cache_free(event_cache, event); |
| 948 | } |
| 949 | |
| 950 | struct lttng_id_tracker *get_tracker(struct lttng_session *session, |
| 951 | enum tracker_type tracker_type) |
| 952 | { |
| 953 | switch (tracker_type) { |
| 954 | case TRACKER_PID: |
| 955 | return &session->pid_tracker; |
| 956 | case TRACKER_VPID: |
| 957 | return &session->vpid_tracker; |
| 958 | case TRACKER_UID: |
| 959 | return &session->uid_tracker; |
| 960 | case TRACKER_VUID: |
| 961 | return &session->vuid_tracker; |
| 962 | case TRACKER_GID: |
| 963 | return &session->gid_tracker; |
| 964 | case TRACKER_VGID: |
| 965 | return &session->vgid_tracker; |
| 966 | default: |
| 967 | WARN_ON_ONCE(1); |
| 968 | return NULL; |
| 969 | } |
| 970 | } |
| 971 | |
| 972 | int lttng_session_track_id(struct lttng_session *session, |
| 973 | enum tracker_type tracker_type, int id) |
| 974 | { |
| 975 | struct lttng_id_tracker *tracker; |
| 976 | int ret; |
| 977 | |
| 978 | tracker = get_tracker(session, tracker_type); |
| 979 | if (!tracker) |
| 980 | return -EINVAL; |
| 981 | if (id < -1) |
| 982 | return -EINVAL; |
| 983 | mutex_lock(&sessions_mutex); |
| 984 | if (id == -1) { |
| 985 | /* track all ids: destroy tracker. */ |
| 986 | lttng_id_tracker_destroy(tracker, true); |
| 987 | ret = 0; |
| 988 | } else { |
| 989 | ret = lttng_id_tracker_add(tracker, id); |
| 990 | } |
| 991 | mutex_unlock(&sessions_mutex); |
| 992 | return ret; |
| 993 | } |
| 994 | |
| 995 | int lttng_session_untrack_id(struct lttng_session *session, |
| 996 | enum tracker_type tracker_type, int id) |
| 997 | { |
| 998 | struct lttng_id_tracker *tracker; |
| 999 | int ret; |
| 1000 | |
| 1001 | tracker = get_tracker(session, tracker_type); |
| 1002 | if (!tracker) |
| 1003 | return -EINVAL; |
| 1004 | if (id < -1) |
| 1005 | return -EINVAL; |
| 1006 | mutex_lock(&sessions_mutex); |
| 1007 | if (id == -1) { |
| 1008 | /* untrack all ids: replace by empty tracker. */ |
| 1009 | ret = lttng_id_tracker_empty_set(tracker); |
| 1010 | } else { |
| 1011 | ret = lttng_id_tracker_del(tracker, id); |
| 1012 | } |
| 1013 | mutex_unlock(&sessions_mutex); |
| 1014 | return ret; |
| 1015 | } |
| 1016 | |
| 1017 | static |
| 1018 | void *id_list_start(struct seq_file *m, loff_t *pos) |
| 1019 | { |
| 1020 | struct lttng_id_tracker *id_tracker = m->private; |
| 1021 | struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p; |
| 1022 | struct lttng_id_hash_node *e; |
| 1023 | int iter = 0, i; |
| 1024 | |
| 1025 | mutex_lock(&sessions_mutex); |
| 1026 | if (id_tracker_p) { |
| 1027 | for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) { |
| 1028 | struct hlist_head *head = &id_tracker_p->id_hash[i]; |
| 1029 | |
| 1030 | lttng_hlist_for_each_entry(e, head, hlist) { |
| 1031 | if (iter++ >= *pos) |
| 1032 | return e; |
| 1033 | } |
| 1034 | } |
| 1035 | } else { |
| 1036 | /* ID tracker disabled. */ |
| 1037 | if (iter >= *pos && iter == 0) { |
| 1038 | return id_tracker_p; /* empty tracker */ |
| 1039 | } |
| 1040 | iter++; |
| 1041 | } |
| 1042 | /* End of list */ |
| 1043 | return NULL; |
| 1044 | } |
| 1045 | |
| 1046 | /* Called with sessions_mutex held. */ |
| 1047 | static |
| 1048 | void *id_list_next(struct seq_file *m, void *p, loff_t *ppos) |
| 1049 | { |
| 1050 | struct lttng_id_tracker *id_tracker = m->private; |
| 1051 | struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p; |
| 1052 | struct lttng_id_hash_node *e; |
| 1053 | int iter = 0, i; |
| 1054 | |
| 1055 | (*ppos)++; |
| 1056 | if (id_tracker_p) { |
| 1057 | for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) { |
| 1058 | struct hlist_head *head = &id_tracker_p->id_hash[i]; |
| 1059 | |
| 1060 | lttng_hlist_for_each_entry(e, head, hlist) { |
| 1061 | if (iter++ >= *ppos) |
| 1062 | return e; |
| 1063 | } |
| 1064 | } |
| 1065 | } else { |
| 1066 | /* ID tracker disabled. */ |
| 1067 | if (iter >= *ppos && iter == 0) |
| 1068 | return p; /* empty tracker */ |
| 1069 | iter++; |
| 1070 | } |
| 1071 | |
| 1072 | /* End of list */ |
| 1073 | return NULL; |
| 1074 | } |
| 1075 | |
| 1076 | static |
| 1077 | void id_list_stop(struct seq_file *m, void *p) |
| 1078 | { |
| 1079 | mutex_unlock(&sessions_mutex); |
| 1080 | } |
| 1081 | |
| 1082 | static |
| 1083 | int id_list_show(struct seq_file *m, void *p) |
| 1084 | { |
| 1085 | struct lttng_id_tracker *id_tracker = m->private; |
| 1086 | struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p; |
| 1087 | int id; |
| 1088 | |
| 1089 | if (p == id_tracker_p) { |
| 1090 | /* Tracker disabled. */ |
| 1091 | id = -1; |
| 1092 | } else { |
| 1093 | const struct lttng_id_hash_node *e = p; |
| 1094 | |
| 1095 | id = lttng_id_tracker_get_node_id(e); |
| 1096 | } |
| 1097 | switch (id_tracker->tracker_type) { |
| 1098 | case TRACKER_PID: |
| 1099 | seq_printf(m, "process { pid = %d; };\n", id); |
| 1100 | break; |
| 1101 | case TRACKER_VPID: |
| 1102 | seq_printf(m, "process { vpid = %d; };\n", id); |
| 1103 | break; |
| 1104 | case TRACKER_UID: |
| 1105 | seq_printf(m, "user { uid = %d; };\n", id); |
| 1106 | break; |
| 1107 | case TRACKER_VUID: |
| 1108 | seq_printf(m, "user { vuid = %d; };\n", id); |
| 1109 | break; |
| 1110 | case TRACKER_GID: |
| 1111 | seq_printf(m, "group { gid = %d; };\n", id); |
| 1112 | break; |
| 1113 | case TRACKER_VGID: |
| 1114 | seq_printf(m, "group { vgid = %d; };\n", id); |
| 1115 | break; |
| 1116 | default: |
| 1117 | seq_printf(m, "UNKNOWN { field = %d };\n", id); |
| 1118 | } |
| 1119 | return 0; |
| 1120 | } |
| 1121 | |
| 1122 | static |
| 1123 | const struct seq_operations lttng_tracker_ids_list_seq_ops = { |
| 1124 | .start = id_list_start, |
| 1125 | .next = id_list_next, |
| 1126 | .stop = id_list_stop, |
| 1127 | .show = id_list_show, |
| 1128 | }; |
| 1129 | |
| 1130 | static |
| 1131 | int lttng_tracker_ids_list_open(struct inode *inode, struct file *file) |
| 1132 | { |
| 1133 | return seq_open(file, <tng_tracker_ids_list_seq_ops); |
| 1134 | } |
| 1135 | |
| 1136 | static |
| 1137 | int lttng_tracker_ids_list_release(struct inode *inode, struct file *file) |
| 1138 | { |
| 1139 | struct seq_file *m = file->private_data; |
| 1140 | struct lttng_id_tracker *id_tracker = m->private; |
| 1141 | int ret; |
| 1142 | |
| 1143 | WARN_ON_ONCE(!id_tracker); |
| 1144 | ret = seq_release(inode, file); |
| 1145 | if (!ret) |
| 1146 | fput(id_tracker->session->file); |
| 1147 | return ret; |
| 1148 | } |
| 1149 | |
| 1150 | const struct file_operations lttng_tracker_ids_list_fops = { |
| 1151 | .owner = THIS_MODULE, |
| 1152 | .open = lttng_tracker_ids_list_open, |
| 1153 | .read = seq_read, |
| 1154 | .llseek = seq_lseek, |
| 1155 | .release = lttng_tracker_ids_list_release, |
| 1156 | }; |
| 1157 | |
| 1158 | int lttng_session_list_tracker_ids(struct lttng_session *session, |
| 1159 | enum tracker_type tracker_type) |
| 1160 | { |
| 1161 | struct file *tracker_ids_list_file; |
| 1162 | struct seq_file *m; |
| 1163 | int file_fd, ret; |
| 1164 | |
| 1165 | file_fd = lttng_get_unused_fd(); |
| 1166 | if (file_fd < 0) { |
| 1167 | ret = file_fd; |
| 1168 | goto fd_error; |
| 1169 | } |
| 1170 | |
| 1171 | tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]", |
| 1172 | <tng_tracker_ids_list_fops, |
| 1173 | NULL, O_RDWR); |
| 1174 | if (IS_ERR(tracker_ids_list_file)) { |
| 1175 | ret = PTR_ERR(tracker_ids_list_file); |
| 1176 | goto file_error; |
| 1177 | } |
| 1178 | if (!atomic_long_add_unless(&session->file->f_count, 1, LONG_MAX)) { |
| 1179 | ret = -EOVERFLOW; |
| 1180 | goto refcount_error; |
| 1181 | } |
| 1182 | ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file); |
| 1183 | if (ret < 0) |
| 1184 | goto open_error; |
| 1185 | m = tracker_ids_list_file->private_data; |
| 1186 | |
| 1187 | m->private = get_tracker(session, tracker_type); |
| 1188 | BUG_ON(!m->private); |
| 1189 | fd_install(file_fd, tracker_ids_list_file); |
| 1190 | |
| 1191 | return file_fd; |
| 1192 | |
| 1193 | open_error: |
| 1194 | atomic_long_dec(&session->file->f_count); |
| 1195 | refcount_error: |
| 1196 | fput(tracker_ids_list_file); |
| 1197 | file_error: |
| 1198 | put_unused_fd(file_fd); |
| 1199 | fd_error: |
| 1200 | return ret; |
| 1201 | } |
| 1202 | |
| 1203 | /* |
| 1204 | * Enabler management. |
| 1205 | */ |
| 1206 | static |
| 1207 | int lttng_match_enabler_star_glob(const char *desc_name, |
| 1208 | const char *pattern) |
| 1209 | { |
| 1210 | if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX, |
| 1211 | desc_name, LTTNG_SIZE_MAX)) |
| 1212 | return 0; |
| 1213 | return 1; |
| 1214 | } |
| 1215 | |
| 1216 | static |
| 1217 | int lttng_match_enabler_name(const char *desc_name, |
| 1218 | const char *name) |
| 1219 | { |
| 1220 | if (strcmp(desc_name, name)) |
| 1221 | return 0; |
| 1222 | return 1; |
| 1223 | } |
| 1224 | |
| 1225 | static |
| 1226 | int lttng_desc_match_enabler(const struct lttng_event_desc *desc, |
| 1227 | struct lttng_enabler *enabler) |
| 1228 | { |
| 1229 | const char *desc_name, *enabler_name; |
| 1230 | |
| 1231 | enabler_name = enabler->event_param.name; |
| 1232 | switch (enabler->event_param.instrumentation) { |
| 1233 | case LTTNG_KERNEL_TRACEPOINT: |
| 1234 | desc_name = desc->name; |
| 1235 | break; |
| 1236 | case LTTNG_KERNEL_SYSCALL: |
| 1237 | desc_name = desc->name; |
| 1238 | if (!strncmp(desc_name, "compat_", strlen("compat_"))) |
| 1239 | desc_name += strlen("compat_"); |
| 1240 | if (!strncmp(desc_name, "syscall_exit_", |
| 1241 | strlen("syscall_exit_"))) { |
| 1242 | desc_name += strlen("syscall_exit_"); |
| 1243 | } else if (!strncmp(desc_name, "syscall_entry_", |
| 1244 | strlen("syscall_entry_"))) { |
| 1245 | desc_name += strlen("syscall_entry_"); |
| 1246 | } else { |
| 1247 | WARN_ON_ONCE(1); |
| 1248 | return -EINVAL; |
| 1249 | } |
| 1250 | break; |
| 1251 | default: |
| 1252 | WARN_ON_ONCE(1); |
| 1253 | return -EINVAL; |
| 1254 | } |
| 1255 | switch (enabler->type) { |
| 1256 | case LTTNG_ENABLER_STAR_GLOB: |
| 1257 | return lttng_match_enabler_star_glob(desc_name, enabler_name); |
| 1258 | case LTTNG_ENABLER_NAME: |
| 1259 | return lttng_match_enabler_name(desc_name, enabler_name); |
| 1260 | default: |
| 1261 | return -EINVAL; |
| 1262 | } |
| 1263 | } |
| 1264 | |
| 1265 | static |
| 1266 | int lttng_event_match_enabler(struct lttng_event *event, |
| 1267 | struct lttng_enabler *enabler) |
| 1268 | { |
| 1269 | if (enabler->event_param.instrumentation != event->instrumentation) |
| 1270 | return 0; |
| 1271 | if (lttng_desc_match_enabler(event->desc, enabler) |
| 1272 | && event->chan == enabler->chan) |
| 1273 | return 1; |
| 1274 | else |
| 1275 | return 0; |
| 1276 | } |
| 1277 | |
| 1278 | static |
| 1279 | struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event, |
| 1280 | struct lttng_enabler *enabler) |
| 1281 | { |
| 1282 | struct lttng_enabler_ref *enabler_ref; |
| 1283 | |
| 1284 | list_for_each_entry(enabler_ref, |
| 1285 | &event->enablers_ref_head, node) { |
| 1286 | if (enabler_ref->ref == enabler) |
| 1287 | return enabler_ref; |
| 1288 | } |
| 1289 | return NULL; |
| 1290 | } |
| 1291 | |
| 1292 | static |
| 1293 | void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) |
| 1294 | { |
| 1295 | struct lttng_session *session = enabler->chan->session; |
| 1296 | struct lttng_probe_desc *probe_desc; |
| 1297 | const struct lttng_event_desc *desc; |
| 1298 | int i; |
| 1299 | struct list_head *probe_list; |
| 1300 | |
| 1301 | probe_list = lttng_get_probe_list_head(); |
| 1302 | /* |
| 1303 | * For each probe event, if we find that a probe event matches |
| 1304 | * our enabler, create an associated lttng_event if not |
| 1305 | * already present. |
| 1306 | */ |
| 1307 | list_for_each_entry(probe_desc, probe_list, head) { |
| 1308 | for (i = 0; i < probe_desc->nr_events; i++) { |
| 1309 | int found = 0; |
| 1310 | struct hlist_head *head; |
| 1311 | const char *event_name; |
| 1312 | size_t name_len; |
| 1313 | uint32_t hash; |
| 1314 | struct lttng_event *event; |
| 1315 | |
| 1316 | desc = probe_desc->event_desc[i]; |
| 1317 | if (!lttng_desc_match_enabler(desc, enabler)) |
| 1318 | continue; |
| 1319 | event_name = desc->name; |
| 1320 | name_len = strlen(event_name); |
| 1321 | |
| 1322 | /* |
| 1323 | * Check if already created. |
| 1324 | */ |
| 1325 | hash = jhash(event_name, name_len, 0); |
| 1326 | head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; |
| 1327 | lttng_hlist_for_each_entry(event, head, hlist) { |
| 1328 | if (event->desc == desc |
| 1329 | && event->chan == enabler->chan) |
| 1330 | found = 1; |
| 1331 | } |
| 1332 | if (found) |
| 1333 | continue; |
| 1334 | |
| 1335 | /* |
| 1336 | * We need to create an event for this |
| 1337 | * event probe. |
| 1338 | */ |
| 1339 | event = _lttng_event_create(enabler->chan, |
| 1340 | NULL, NULL, desc, |
| 1341 | LTTNG_KERNEL_TRACEPOINT); |
| 1342 | if (!event) { |
| 1343 | printk(KERN_INFO "Unable to create event %s\n", |
| 1344 | probe_desc->event_desc[i]->name); |
| 1345 | } |
| 1346 | } |
| 1347 | } |
| 1348 | } |
| 1349 | |
| 1350 | static |
| 1351 | void lttng_create_syscall_if_missing(struct lttng_enabler *enabler) |
| 1352 | { |
| 1353 | int ret; |
| 1354 | |
| 1355 | ret = lttng_syscalls_register(enabler->chan, NULL); |
| 1356 | WARN_ON_ONCE(ret); |
| 1357 | } |
| 1358 | |
| 1359 | /* |
| 1360 | * Create struct lttng_event if it is missing and present in the list of |
| 1361 | * tracepoint probes. |
| 1362 | * Should be called with sessions mutex held. |
| 1363 | */ |
| 1364 | static |
| 1365 | void lttng_create_event_if_missing(struct lttng_enabler *enabler) |
| 1366 | { |
| 1367 | switch (enabler->event_param.instrumentation) { |
| 1368 | case LTTNG_KERNEL_TRACEPOINT: |
| 1369 | lttng_create_tracepoint_if_missing(enabler); |
| 1370 | break; |
| 1371 | case LTTNG_KERNEL_SYSCALL: |
| 1372 | lttng_create_syscall_if_missing(enabler); |
| 1373 | break; |
| 1374 | default: |
| 1375 | WARN_ON_ONCE(1); |
| 1376 | break; |
| 1377 | } |
| 1378 | } |
| 1379 | |
| 1380 | /* |
| 1381 | * Create events associated with an enabler (if not already present), |
| 1382 | * and add backward reference from the event to the enabler. |
| 1383 | * Should be called with sessions mutex held. |
| 1384 | */ |
| 1385 | static |
| 1386 | int lttng_enabler_ref_events(struct lttng_enabler *enabler) |
| 1387 | { |
| 1388 | struct lttng_session *session = enabler->chan->session; |
| 1389 | struct lttng_event *event; |
| 1390 | |
| 1391 | /* First ensure that probe events are created for this enabler. */ |
| 1392 | lttng_create_event_if_missing(enabler); |
| 1393 | |
| 1394 | /* For each event matching enabler in session event list. */ |
| 1395 | list_for_each_entry(event, &session->events, list) { |
| 1396 | struct lttng_enabler_ref *enabler_ref; |
| 1397 | |
| 1398 | if (!lttng_event_match_enabler(event, enabler)) |
| 1399 | continue; |
| 1400 | enabler_ref = lttng_event_enabler_ref(event, enabler); |
| 1401 | if (!enabler_ref) { |
| 1402 | /* |
| 1403 | * If no backward ref, create it. |
| 1404 | * Add backward ref from event to enabler. |
| 1405 | */ |
| 1406 | enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL); |
| 1407 | if (!enabler_ref) |
| 1408 | return -ENOMEM; |
| 1409 | enabler_ref->ref = enabler; |
| 1410 | list_add(&enabler_ref->node, |
| 1411 | &event->enablers_ref_head); |
| 1412 | } |
| 1413 | |
| 1414 | /* |
| 1415 | * Link filter bytecodes if not linked yet. |
| 1416 | */ |
| 1417 | lttng_enabler_event_link_bytecode(event, enabler); |
| 1418 | |
| 1419 | /* TODO: merge event context. */ |
| 1420 | } |
| 1421 | return 0; |
| 1422 | } |
| 1423 | |
| 1424 | /* |
| 1425 | * Called at module load: connect the probe on all enablers matching |
| 1426 | * this event. |
| 1427 | * Called with sessions lock held. |
| 1428 | */ |
| 1429 | int lttng_fix_pending_events(void) |
| 1430 | { |
| 1431 | struct lttng_session *session; |
| 1432 | |
| 1433 | list_for_each_entry(session, &sessions, list) |
| 1434 | lttng_session_lazy_sync_enablers(session); |
| 1435 | return 0; |
| 1436 | } |
| 1437 | |
| 1438 | struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, |
| 1439 | struct lttng_kernel_event *event_param, |
| 1440 | struct lttng_channel *chan) |
| 1441 | { |
| 1442 | struct lttng_enabler *enabler; |
| 1443 | |
| 1444 | enabler = kzalloc(sizeof(*enabler), GFP_KERNEL); |
| 1445 | if (!enabler) |
| 1446 | return NULL; |
| 1447 | enabler->type = type; |
| 1448 | INIT_LIST_HEAD(&enabler->filter_bytecode_head); |
| 1449 | memcpy(&enabler->event_param, event_param, |
| 1450 | sizeof(enabler->event_param)); |
| 1451 | enabler->chan = chan; |
| 1452 | /* ctx left NULL */ |
| 1453 | enabler->enabled = 0; |
| 1454 | enabler->evtype = LTTNG_TYPE_ENABLER; |
| 1455 | mutex_lock(&sessions_mutex); |
| 1456 | list_add(&enabler->node, &enabler->chan->session->enablers_head); |
| 1457 | lttng_session_lazy_sync_enablers(enabler->chan->session); |
| 1458 | mutex_unlock(&sessions_mutex); |
| 1459 | return enabler; |
| 1460 | } |
| 1461 | |
| 1462 | int lttng_enabler_enable(struct lttng_enabler *enabler) |
| 1463 | { |
| 1464 | mutex_lock(&sessions_mutex); |
| 1465 | enabler->enabled = 1; |
| 1466 | lttng_session_lazy_sync_enablers(enabler->chan->session); |
| 1467 | mutex_unlock(&sessions_mutex); |
| 1468 | return 0; |
| 1469 | } |
| 1470 | |
| 1471 | int lttng_enabler_disable(struct lttng_enabler *enabler) |
| 1472 | { |
| 1473 | mutex_lock(&sessions_mutex); |
| 1474 | enabler->enabled = 0; |
| 1475 | lttng_session_lazy_sync_enablers(enabler->chan->session); |
| 1476 | mutex_unlock(&sessions_mutex); |
| 1477 | return 0; |
| 1478 | } |
| 1479 | |
| 1480 | int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler, |
| 1481 | struct lttng_kernel_filter_bytecode __user *bytecode) |
| 1482 | { |
| 1483 | struct lttng_filter_bytecode_node *bytecode_node; |
| 1484 | uint32_t bytecode_len; |
| 1485 | int ret; |
| 1486 | |
| 1487 | ret = get_user(bytecode_len, &bytecode->len); |
| 1488 | if (ret) |
| 1489 | return ret; |
| 1490 | bytecode_node = kzalloc(sizeof(*bytecode_node) + bytecode_len, |
| 1491 | GFP_KERNEL); |
| 1492 | if (!bytecode_node) |
| 1493 | return -ENOMEM; |
| 1494 | ret = copy_from_user(&bytecode_node->bc, bytecode, |
| 1495 | sizeof(*bytecode) + bytecode_len); |
| 1496 | if (ret) |
| 1497 | goto error_free; |
| 1498 | bytecode_node->enabler = enabler; |
| 1499 | /* Enforce length based on allocated size */ |
| 1500 | bytecode_node->bc.len = bytecode_len; |
| 1501 | list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head); |
| 1502 | lttng_session_lazy_sync_enablers(enabler->chan->session); |
| 1503 | return 0; |
| 1504 | |
| 1505 | error_free: |
| 1506 | kfree(bytecode_node); |
| 1507 | return ret; |
| 1508 | } |
| 1509 | |
| 1510 | int lttng_event_add_callsite(struct lttng_event *event, |
| 1511 | struct lttng_kernel_event_callsite __user *callsite) |
| 1512 | { |
| 1513 | |
| 1514 | switch (event->instrumentation) { |
| 1515 | case LTTNG_KERNEL_UPROBE: |
| 1516 | return lttng_uprobes_add_callsite(event, callsite); |
| 1517 | default: |
| 1518 | return -EINVAL; |
| 1519 | } |
| 1520 | } |
| 1521 | |
| 1522 | int lttng_enabler_attach_context(struct lttng_enabler *enabler, |
| 1523 | struct lttng_kernel_context *context_param) |
| 1524 | { |
| 1525 | return -ENOSYS; |
| 1526 | } |
| 1527 | |
| 1528 | static |
| 1529 | void lttng_enabler_destroy(struct lttng_enabler *enabler) |
| 1530 | { |
| 1531 | struct lttng_filter_bytecode_node *filter_node, *tmp_filter_node; |
| 1532 | |
| 1533 | /* Destroy filter bytecode */ |
| 1534 | list_for_each_entry_safe(filter_node, tmp_filter_node, |
| 1535 | &enabler->filter_bytecode_head, node) { |
| 1536 | kfree(filter_node); |
| 1537 | } |
| 1538 | |
| 1539 | /* Destroy contexts */ |
| 1540 | lttng_destroy_context(enabler->ctx); |
| 1541 | |
| 1542 | list_del(&enabler->node); |
| 1543 | kfree(enabler); |
| 1544 | } |
| 1545 | |
| 1546 | /* |
| 1547 | * lttng_session_sync_enablers should be called just before starting a |
| 1548 | * session. |
| 1549 | * Should be called with sessions mutex held. |
| 1550 | */ |
| 1551 | static |
| 1552 | void lttng_session_sync_enablers(struct lttng_session *session) |
| 1553 | { |
| 1554 | struct lttng_enabler *enabler; |
| 1555 | struct lttng_event *event; |
| 1556 | |
| 1557 | list_for_each_entry(enabler, &session->enablers_head, node) |
| 1558 | lttng_enabler_ref_events(enabler); |
| 1559 | /* |
| 1560 | * For each event, if at least one of its enablers is enabled, |
| 1561 | * and its channel and session transient states are enabled, we |
| 1562 | * enable the event, else we disable it. |
| 1563 | */ |
| 1564 | list_for_each_entry(event, &session->events, list) { |
| 1565 | struct lttng_enabler_ref *enabler_ref; |
| 1566 | struct lttng_bytecode_runtime *runtime; |
| 1567 | int enabled = 0, has_enablers_without_bytecode = 0; |
| 1568 | |
| 1569 | switch (event->instrumentation) { |
| 1570 | case LTTNG_KERNEL_TRACEPOINT: |
| 1571 | case LTTNG_KERNEL_SYSCALL: |
| 1572 | /* Enable events */ |
| 1573 | list_for_each_entry(enabler_ref, |
| 1574 | &event->enablers_ref_head, node) { |
| 1575 | if (enabler_ref->ref->enabled) { |
| 1576 | enabled = 1; |
| 1577 | break; |
| 1578 | } |
| 1579 | } |
| 1580 | break; |
| 1581 | default: |
| 1582 | /* Not handled with lazy sync. */ |
| 1583 | continue; |
| 1584 | } |
| 1585 | /* |
| 1586 | * Enabled state is based on union of enablers, with |
| 1587 | * intesection of session and channel transient enable |
| 1588 | * states. |
| 1589 | */ |
| 1590 | enabled = enabled && session->tstate && event->chan->tstate; |
| 1591 | |
| 1592 | WRITE_ONCE(event->enabled, enabled); |
| 1593 | /* |
| 1594 | * Sync tracepoint registration with event enabled |
| 1595 | * state. |
| 1596 | */ |
| 1597 | if (enabled) { |
| 1598 | register_event(event); |
| 1599 | } else { |
| 1600 | _lttng_event_unregister(event); |
| 1601 | } |
| 1602 | |
| 1603 | /* Check if has enablers without bytecode enabled */ |
| 1604 | list_for_each_entry(enabler_ref, |
| 1605 | &event->enablers_ref_head, node) { |
| 1606 | if (enabler_ref->ref->enabled |
| 1607 | && list_empty(&enabler_ref->ref->filter_bytecode_head)) { |
| 1608 | has_enablers_without_bytecode = 1; |
| 1609 | break; |
| 1610 | } |
| 1611 | } |
| 1612 | event->has_enablers_without_bytecode = |
| 1613 | has_enablers_without_bytecode; |
| 1614 | |
| 1615 | /* Enable filters */ |
| 1616 | list_for_each_entry(runtime, |
| 1617 | &event->bytecode_runtime_head, node) |
| 1618 | lttng_filter_sync_state(runtime); |
| 1619 | } |
| 1620 | } |
| 1621 | |
| 1622 | /* |
| 1623 | * Apply enablers to session events, adding events to session if need |
| 1624 | * be. It is required after each modification applied to an active |
| 1625 | * session, and right before session "start". |
| 1626 | * "lazy" sync means we only sync if required. |
| 1627 | * Should be called with sessions mutex held. |
| 1628 | */ |
| 1629 | static |
| 1630 | void lttng_session_lazy_sync_enablers(struct lttng_session *session) |
| 1631 | { |
| 1632 | /* We can skip if session is not active */ |
| 1633 | if (!session->active) |
| 1634 | return; |
| 1635 | lttng_session_sync_enablers(session); |
| 1636 | } |
| 1637 | |
| 1638 | /* |
| 1639 | * Serialize at most one packet worth of metadata into a metadata |
| 1640 | * channel. |
| 1641 | * We grab the metadata cache mutex to get exclusive access to our metadata |
| 1642 | * buffer and to the metadata cache. Exclusive access to the metadata buffer |
| 1643 | * allows us to do racy operations such as looking for remaining space left in |
| 1644 | * packet and write, since mutual exclusion protects us from concurrent writes. |
| 1645 | * Mutual exclusion on the metadata cache allow us to read the cache content |
| 1646 | * without racing against reallocation of the cache by updates. |
| 1647 | * Returns the number of bytes written in the channel, 0 if no data |
| 1648 | * was written and a negative value on error. |
| 1649 | */ |
| 1650 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
| 1651 | struct channel *chan) |
| 1652 | { |
| 1653 | struct lib_ring_buffer_ctx ctx; |
| 1654 | int ret = 0; |
| 1655 | size_t len, reserve_len; |
| 1656 | |
| 1657 | /* |
| 1658 | * Ensure we support mutiple get_next / put sequences followed by |
| 1659 | * put_next. The metadata cache lock protects reading the metadata |
| 1660 | * cache. It can indeed be read concurrently by "get_next_subbuf" and |
| 1661 | * "flush" operations on the buffer invoked by different processes. |
| 1662 | * Moreover, since the metadata cache memory can be reallocated, we |
| 1663 | * need to have exclusive access against updates even though we only |
| 1664 | * read it. |
| 1665 | */ |
| 1666 | mutex_lock(&stream->metadata_cache->lock); |
| 1667 | WARN_ON(stream->metadata_in < stream->metadata_out); |
| 1668 | if (stream->metadata_in != stream->metadata_out) |
| 1669 | goto end; |
| 1670 | |
| 1671 | /* Metadata regenerated, change the version. */ |
| 1672 | if (stream->metadata_cache->version != stream->version) |
| 1673 | stream->version = stream->metadata_cache->version; |
| 1674 | |
| 1675 | len = stream->metadata_cache->metadata_written - |
| 1676 | stream->metadata_in; |
| 1677 | if (!len) |
| 1678 | goto end; |
| 1679 | reserve_len = min_t(size_t, |
| 1680 | stream->transport->ops.packet_avail_size(chan), |
| 1681 | len); |
| 1682 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
| 1683 | sizeof(char), -1); |
| 1684 | /* |
| 1685 | * If reservation failed, return an error to the caller. |
| 1686 | */ |
| 1687 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
| 1688 | if (ret != 0) { |
| 1689 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); |
| 1690 | goto end; |
| 1691 | } |
| 1692 | stream->transport->ops.event_write(&ctx, |
| 1693 | stream->metadata_cache->data + stream->metadata_in, |
| 1694 | reserve_len); |
| 1695 | stream->transport->ops.event_commit(&ctx); |
| 1696 | stream->metadata_in += reserve_len; |
| 1697 | ret = reserve_len; |
| 1698 | |
| 1699 | end: |
| 1700 | mutex_unlock(&stream->metadata_cache->lock); |
| 1701 | return ret; |
| 1702 | } |
| 1703 | |
| 1704 | /* |
| 1705 | * Write the metadata to the metadata cache. |
| 1706 | * Must be called with sessions_mutex held. |
| 1707 | * The metadata cache lock protects us from concurrent read access from |
| 1708 | * thread outputting metadata content to ring buffer. |
| 1709 | */ |
| 1710 | int lttng_metadata_printf(struct lttng_session *session, |
| 1711 | const char *fmt, ...) |
| 1712 | { |
| 1713 | char *str; |
| 1714 | size_t len; |
| 1715 | va_list ap; |
| 1716 | struct lttng_metadata_stream *stream; |
| 1717 | |
| 1718 | WARN_ON_ONCE(!READ_ONCE(session->active)); |
| 1719 | |
| 1720 | va_start(ap, fmt); |
| 1721 | str = kvasprintf(GFP_KERNEL, fmt, ap); |
| 1722 | va_end(ap); |
| 1723 | if (!str) |
| 1724 | return -ENOMEM; |
| 1725 | |
| 1726 | len = strlen(str); |
| 1727 | mutex_lock(&session->metadata_cache->lock); |
| 1728 | if (session->metadata_cache->metadata_written + len > |
| 1729 | session->metadata_cache->cache_alloc) { |
| 1730 | char *tmp_cache_realloc; |
| 1731 | unsigned int tmp_cache_alloc_size; |
| 1732 | |
| 1733 | tmp_cache_alloc_size = max_t(unsigned int, |
| 1734 | session->metadata_cache->cache_alloc + len, |
| 1735 | session->metadata_cache->cache_alloc << 1); |
| 1736 | tmp_cache_realloc = vzalloc(tmp_cache_alloc_size); |
| 1737 | if (!tmp_cache_realloc) |
| 1738 | goto err; |
| 1739 | if (session->metadata_cache->data) { |
| 1740 | memcpy(tmp_cache_realloc, |
| 1741 | session->metadata_cache->data, |
| 1742 | session->metadata_cache->cache_alloc); |
| 1743 | vfree(session->metadata_cache->data); |
| 1744 | } |
| 1745 | |
| 1746 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; |
| 1747 | session->metadata_cache->data = tmp_cache_realloc; |
| 1748 | } |
| 1749 | memcpy(session->metadata_cache->data + |
| 1750 | session->metadata_cache->metadata_written, |
| 1751 | str, len); |
| 1752 | session->metadata_cache->metadata_written += len; |
| 1753 | mutex_unlock(&session->metadata_cache->lock); |
| 1754 | kfree(str); |
| 1755 | |
| 1756 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) |
| 1757 | wake_up_interruptible(&stream->read_wait); |
| 1758 | |
| 1759 | return 0; |
| 1760 | |
| 1761 | err: |
| 1762 | mutex_unlock(&session->metadata_cache->lock); |
| 1763 | kfree(str); |
| 1764 | return -ENOMEM; |
| 1765 | } |
| 1766 | |
| 1767 | static |
| 1768 | int print_tabs(struct lttng_session *session, size_t nesting) |
| 1769 | { |
| 1770 | size_t i; |
| 1771 | |
| 1772 | for (i = 0; i < nesting; i++) { |
| 1773 | int ret; |
| 1774 | |
| 1775 | ret = lttng_metadata_printf(session, " "); |
| 1776 | if (ret) { |
| 1777 | return ret; |
| 1778 | } |
| 1779 | } |
| 1780 | return 0; |
| 1781 | } |
| 1782 | |
| 1783 | /* |
| 1784 | * Must be called with sessions_mutex held. |
| 1785 | */ |
| 1786 | static |
| 1787 | int _lttng_struct_type_statedump(struct lttng_session *session, |
| 1788 | const struct lttng_type *type, |
| 1789 | size_t nesting) |
| 1790 | { |
| 1791 | int ret; |
| 1792 | uint32_t i, nr_fields; |
| 1793 | |
| 1794 | ret = print_tabs(session, nesting); |
| 1795 | if (ret) |
| 1796 | return ret; |
| 1797 | ret = lttng_metadata_printf(session, |
| 1798 | "struct {\n"); |
| 1799 | if (ret) |
| 1800 | return ret; |
| 1801 | nr_fields = type->u._struct.nr_fields; |
| 1802 | for (i = 0; i < nr_fields; i++) { |
| 1803 | const struct lttng_event_field *iter_field; |
| 1804 | |
| 1805 | iter_field = &type->u._struct.fields[i]; |
| 1806 | ret = _lttng_field_statedump(session, iter_field, nesting + 1); |
| 1807 | if (ret) |
| 1808 | return ret; |
| 1809 | } |
| 1810 | ret = print_tabs(session, nesting); |
| 1811 | if (ret) |
| 1812 | return ret; |
| 1813 | ret = lttng_metadata_printf(session, |
| 1814 | "}"); |
| 1815 | return ret; |
| 1816 | } |
| 1817 | |
| 1818 | /* |
| 1819 | * Must be called with sessions_mutex held. |
| 1820 | */ |
| 1821 | static |
| 1822 | int _lttng_struct_statedump(struct lttng_session *session, |
| 1823 | const struct lttng_event_field *field, |
| 1824 | size_t nesting) |
| 1825 | { |
| 1826 | int ret; |
| 1827 | |
| 1828 | ret = _lttng_struct_type_statedump(session, |
| 1829 | &field->type, nesting); |
| 1830 | if (ret) |
| 1831 | return ret; |
| 1832 | ret = lttng_metadata_printf(session, |
| 1833 | "_%s;\n", |
| 1834 | field->name); |
| 1835 | return ret; |
| 1836 | } |
| 1837 | |
| 1838 | /* |
| 1839 | * Must be called with sessions_mutex held. |
| 1840 | */ |
| 1841 | static |
| 1842 | int _lttng_variant_type_statedump(struct lttng_session *session, |
| 1843 | const struct lttng_type *type, |
| 1844 | size_t nesting) |
| 1845 | { |
| 1846 | int ret; |
| 1847 | uint32_t i, nr_choices; |
| 1848 | |
| 1849 | ret = print_tabs(session, nesting); |
| 1850 | if (ret) |
| 1851 | return ret; |
| 1852 | ret = lttng_metadata_printf(session, |
| 1853 | "variant <_%s> {\n", |
| 1854 | type->u.variant.tag_name); |
| 1855 | if (ret) |
| 1856 | return ret; |
| 1857 | nr_choices = type->u.variant.nr_choices; |
| 1858 | for (i = 0; i < nr_choices; i++) { |
| 1859 | const struct lttng_event_field *iter_field; |
| 1860 | |
| 1861 | iter_field = &type->u.variant.choices[i]; |
| 1862 | ret = _lttng_field_statedump(session, iter_field, nesting + 1); |
| 1863 | if (ret) |
| 1864 | return ret; |
| 1865 | } |
| 1866 | ret = print_tabs(session, nesting); |
| 1867 | if (ret) |
| 1868 | return ret; |
| 1869 | ret = lttng_metadata_printf(session, |
| 1870 | "}"); |
| 1871 | return ret; |
| 1872 | } |
| 1873 | |
| 1874 | /* |
| 1875 | * Must be called with sessions_mutex held. |
| 1876 | */ |
| 1877 | static |
| 1878 | int _lttng_variant_statedump(struct lttng_session *session, |
| 1879 | const struct lttng_event_field *field, |
| 1880 | size_t nesting) |
| 1881 | { |
| 1882 | int ret; |
| 1883 | |
| 1884 | ret = _lttng_variant_type_statedump(session, |
| 1885 | &field->type, nesting); |
| 1886 | if (ret) |
| 1887 | return ret; |
| 1888 | ret = lttng_metadata_printf(session, |
| 1889 | "_%s;\n", |
| 1890 | field->name); |
| 1891 | return ret; |
| 1892 | } |
| 1893 | |
| 1894 | /* |
| 1895 | * Must be called with sessions_mutex held. |
| 1896 | */ |
| 1897 | static |
| 1898 | int _lttng_array_compound_statedump(struct lttng_session *session, |
| 1899 | const struct lttng_event_field *field, |
| 1900 | size_t nesting) |
| 1901 | { |
| 1902 | int ret; |
| 1903 | const struct lttng_type *elem_type; |
| 1904 | |
| 1905 | /* Only array of structures and variants are currently supported. */ |
| 1906 | elem_type = field->type.u.array_compound.elem_type; |
| 1907 | switch (elem_type->atype) { |
| 1908 | case atype_struct: |
| 1909 | ret = _lttng_struct_type_statedump(session, elem_type, nesting); |
| 1910 | if (ret) |
| 1911 | return ret; |
| 1912 | break; |
| 1913 | case atype_variant: |
| 1914 | ret = _lttng_variant_type_statedump(session, elem_type, nesting); |
| 1915 | if (ret) |
| 1916 | return ret; |
| 1917 | break; |
| 1918 | default: |
| 1919 | return -EINVAL; |
| 1920 | } |
| 1921 | ret = lttng_metadata_printf(session, |
| 1922 | " _%s[%u];\n", |
| 1923 | field->name, |
| 1924 | field->type.u.array_compound.length); |
| 1925 | return ret; |
| 1926 | } |
| 1927 | |
| 1928 | /* |
| 1929 | * Must be called with sessions_mutex held. |
| 1930 | */ |
| 1931 | static |
| 1932 | int _lttng_sequence_compound_statedump(struct lttng_session *session, |
| 1933 | const struct lttng_event_field *field, |
| 1934 | size_t nesting) |
| 1935 | { |
| 1936 | int ret; |
| 1937 | const char *length_name; |
| 1938 | const struct lttng_type *elem_type; |
| 1939 | |
| 1940 | length_name = field->type.u.sequence_compound.length_name; |
| 1941 | |
| 1942 | /* Only array of structures and variants are currently supported. */ |
| 1943 | elem_type = field->type.u.sequence_compound.elem_type; |
| 1944 | switch (elem_type->atype) { |
| 1945 | case atype_struct: |
| 1946 | ret = _lttng_struct_type_statedump(session, elem_type, nesting); |
| 1947 | if (ret) |
| 1948 | return ret; |
| 1949 | break; |
| 1950 | case atype_variant: |
| 1951 | ret = _lttng_variant_type_statedump(session, elem_type, nesting); |
| 1952 | if (ret) |
| 1953 | return ret; |
| 1954 | break; |
| 1955 | default: |
| 1956 | return -EINVAL; |
| 1957 | } |
| 1958 | ret = lttng_metadata_printf(session, |
| 1959 | " _%s[ _%s ];\n", |
| 1960 | field->name, |
| 1961 | length_name); |
| 1962 | return ret; |
| 1963 | } |
| 1964 | |
| 1965 | /* |
| 1966 | * Must be called with sessions_mutex held. |
| 1967 | */ |
| 1968 | static |
| 1969 | int _lttng_enum_statedump(struct lttng_session *session, |
| 1970 | const struct lttng_event_field *field, |
| 1971 | size_t nesting) |
| 1972 | { |
| 1973 | const struct lttng_enum_desc *enum_desc; |
| 1974 | const struct lttng_integer_type *container_type; |
| 1975 | int ret; |
| 1976 | unsigned int i, nr_entries; |
| 1977 | |
| 1978 | enum_desc = field->type.u.basic.enumeration.desc; |
| 1979 | container_type = &field->type.u.basic.enumeration.container_type; |
| 1980 | nr_entries = enum_desc->nr_entries; |
| 1981 | |
| 1982 | ret = print_tabs(session, nesting); |
| 1983 | if (ret) |
| 1984 | goto end; |
| 1985 | ret = lttng_metadata_printf(session, |
| 1986 | "enum : integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } {\n", |
| 1987 | container_type->size, |
| 1988 | container_type->alignment, |
| 1989 | container_type->signedness, |
| 1990 | (container_type->encoding == lttng_encode_none) |
| 1991 | ? "none" |
| 1992 | : (container_type->encoding == lttng_encode_UTF8) |
| 1993 | ? "UTF8" |
| 1994 | : "ASCII", |
| 1995 | container_type->base, |
| 1996 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 1997 | container_type->reverse_byte_order ? " byte_order = le;" : "" |
| 1998 | #else |
| 1999 | container_type->reverse_byte_order ? " byte_order = be;" : "" |
| 2000 | #endif |
| 2001 | ); |
| 2002 | if (ret) |
| 2003 | goto end; |
| 2004 | /* Dump all entries */ |
| 2005 | for (i = 0; i < nr_entries; i++) { |
| 2006 | const struct lttng_enum_entry *entry = &enum_desc->entries[i]; |
| 2007 | int j, len; |
| 2008 | |
| 2009 | ret = print_tabs(session, nesting + 1); |
| 2010 | if (ret) |
| 2011 | goto end; |
| 2012 | ret = lttng_metadata_printf(session, |
| 2013 | "\""); |
| 2014 | if (ret) |
| 2015 | goto end; |
| 2016 | len = strlen(entry->string); |
| 2017 | /* Escape the character '"' */ |
| 2018 | for (j = 0; j < len; j++) { |
| 2019 | char c = entry->string[j]; |
| 2020 | |
| 2021 | switch (c) { |
| 2022 | case '"': |
| 2023 | ret = lttng_metadata_printf(session, |
| 2024 | "\\\""); |
| 2025 | break; |
| 2026 | case '\\': |
| 2027 | ret = lttng_metadata_printf(session, |
| 2028 | "\\\\"); |
| 2029 | break; |
| 2030 | default: |
| 2031 | ret = lttng_metadata_printf(session, |
| 2032 | "%c", c); |
| 2033 | break; |
| 2034 | } |
| 2035 | if (ret) |
| 2036 | goto end; |
| 2037 | } |
| 2038 | ret = lttng_metadata_printf(session, "\""); |
| 2039 | if (ret) |
| 2040 | goto end; |
| 2041 | |
| 2042 | if (entry->options.is_auto) { |
| 2043 | ret = lttng_metadata_printf(session, ",\n"); |
| 2044 | if (ret) |
| 2045 | goto end; |
| 2046 | } else { |
| 2047 | ret = lttng_metadata_printf(session, |
| 2048 | " = "); |
| 2049 | if (ret) |
| 2050 | goto end; |
| 2051 | if (entry->start.signedness) |
| 2052 | ret = lttng_metadata_printf(session, |
| 2053 | "%lld", (long long) entry->start.value); |
| 2054 | else |
| 2055 | ret = lttng_metadata_printf(session, |
| 2056 | "%llu", entry->start.value); |
| 2057 | if (ret) |
| 2058 | goto end; |
| 2059 | if (entry->start.signedness == entry->end.signedness && |
| 2060 | entry->start.value |
| 2061 | == entry->end.value) { |
| 2062 | ret = lttng_metadata_printf(session, |
| 2063 | ",\n"); |
| 2064 | } else { |
| 2065 | if (entry->end.signedness) { |
| 2066 | ret = lttng_metadata_printf(session, |
| 2067 | " ... %lld,\n", |
| 2068 | (long long) entry->end.value); |
| 2069 | } else { |
| 2070 | ret = lttng_metadata_printf(session, |
| 2071 | " ... %llu,\n", |
| 2072 | entry->end.value); |
| 2073 | } |
| 2074 | } |
| 2075 | if (ret) |
| 2076 | goto end; |
| 2077 | } |
| 2078 | } |
| 2079 | ret = print_tabs(session, nesting); |
| 2080 | if (ret) |
| 2081 | goto end; |
| 2082 | ret = lttng_metadata_printf(session, "} _%s;\n", |
| 2083 | field->name); |
| 2084 | end: |
| 2085 | return ret; |
| 2086 | } |
| 2087 | |
| 2088 | /* |
| 2089 | * Must be called with sessions_mutex held. |
| 2090 | */ |
| 2091 | static |
| 2092 | int _lttng_field_statedump(struct lttng_session *session, |
| 2093 | const struct lttng_event_field *field, |
| 2094 | size_t nesting) |
| 2095 | { |
| 2096 | int ret = 0; |
| 2097 | |
| 2098 | switch (field->type.atype) { |
| 2099 | case atype_integer: |
| 2100 | ret = print_tabs(session, nesting); |
| 2101 | if (ret) |
| 2102 | return ret; |
| 2103 | ret = lttng_metadata_printf(session, |
| 2104 | "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
| 2105 | field->type.u.basic.integer.size, |
| 2106 | field->type.u.basic.integer.alignment, |
| 2107 | field->type.u.basic.integer.signedness, |
| 2108 | (field->type.u.basic.integer.encoding == lttng_encode_none) |
| 2109 | ? "none" |
| 2110 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) |
| 2111 | ? "UTF8" |
| 2112 | : "ASCII", |
| 2113 | field->type.u.basic.integer.base, |
| 2114 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 2115 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 2116 | #else |
| 2117 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 2118 | #endif |
| 2119 | field->name); |
| 2120 | break; |
| 2121 | case atype_enum: |
| 2122 | ret = _lttng_enum_statedump(session, field, nesting); |
| 2123 | break; |
| 2124 | case atype_array: |
| 2125 | case atype_array_bitfield: |
| 2126 | { |
| 2127 | const struct lttng_basic_type *elem_type; |
| 2128 | |
| 2129 | elem_type = &field->type.u.array.elem_type; |
| 2130 | if (field->type.u.array.elem_alignment) { |
| 2131 | ret = print_tabs(session, nesting); |
| 2132 | if (ret) |
| 2133 | return ret; |
| 2134 | ret = lttng_metadata_printf(session, |
| 2135 | "struct { } align(%u) _%s_padding;\n", |
| 2136 | field->type.u.array.elem_alignment * CHAR_BIT, |
| 2137 | field->name); |
| 2138 | if (ret) |
| 2139 | return ret; |
| 2140 | } |
| 2141 | ret = print_tabs(session, nesting); |
| 2142 | if (ret) |
| 2143 | return ret; |
| 2144 | ret = lttng_metadata_printf(session, |
| 2145 | "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
| 2146 | elem_type->u.basic.integer.size, |
| 2147 | elem_type->u.basic.integer.alignment, |
| 2148 | elem_type->u.basic.integer.signedness, |
| 2149 | (elem_type->u.basic.integer.encoding == lttng_encode_none) |
| 2150 | ? "none" |
| 2151 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 2152 | ? "UTF8" |
| 2153 | : "ASCII", |
| 2154 | elem_type->u.basic.integer.base, |
| 2155 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 2156 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 2157 | #else |
| 2158 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 2159 | #endif |
| 2160 | field->name, field->type.u.array.length); |
| 2161 | break; |
| 2162 | } |
| 2163 | case atype_sequence: |
| 2164 | case atype_sequence_bitfield: |
| 2165 | { |
| 2166 | const struct lttng_basic_type *elem_type; |
| 2167 | const struct lttng_basic_type *length_type; |
| 2168 | |
| 2169 | elem_type = &field->type.u.sequence.elem_type; |
| 2170 | length_type = &field->type.u.sequence.length_type; |
| 2171 | ret = print_tabs(session, nesting); |
| 2172 | if (ret) |
| 2173 | return ret; |
| 2174 | ret = lttng_metadata_printf(session, |
| 2175 | "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", |
| 2176 | length_type->u.basic.integer.size, |
| 2177 | (unsigned int) length_type->u.basic.integer.alignment, |
| 2178 | length_type->u.basic.integer.signedness, |
| 2179 | (length_type->u.basic.integer.encoding == lttng_encode_none) |
| 2180 | ? "none" |
| 2181 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 2182 | ? "UTF8" |
| 2183 | : "ASCII"), |
| 2184 | length_type->u.basic.integer.base, |
| 2185 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 2186 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 2187 | #else |
| 2188 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 2189 | #endif |
| 2190 | field->name); |
| 2191 | if (ret) |
| 2192 | return ret; |
| 2193 | |
| 2194 | if (field->type.u.sequence.elem_alignment) { |
| 2195 | ret = print_tabs(session, nesting); |
| 2196 | if (ret) |
| 2197 | return ret; |
| 2198 | ret = lttng_metadata_printf(session, |
| 2199 | "struct { } align(%u) _%s_padding;\n", |
| 2200 | field->type.u.sequence.elem_alignment * CHAR_BIT, |
| 2201 | field->name); |
| 2202 | if (ret) |
| 2203 | return ret; |
| 2204 | } |
| 2205 | ret = print_tabs(session, nesting); |
| 2206 | if (ret) |
| 2207 | return ret; |
| 2208 | ret = lttng_metadata_printf(session, |
| 2209 | "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
| 2210 | elem_type->u.basic.integer.size, |
| 2211 | (unsigned int) elem_type->u.basic.integer.alignment, |
| 2212 | elem_type->u.basic.integer.signedness, |
| 2213 | (elem_type->u.basic.integer.encoding == lttng_encode_none) |
| 2214 | ? "none" |
| 2215 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
| 2216 | ? "UTF8" |
| 2217 | : "ASCII"), |
| 2218 | elem_type->u.basic.integer.base, |
| 2219 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 2220 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
| 2221 | #else |
| 2222 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
| 2223 | #endif |
| 2224 | field->name, |
| 2225 | field->name); |
| 2226 | break; |
| 2227 | } |
| 2228 | |
| 2229 | case atype_string: |
| 2230 | /* Default encoding is UTF8 */ |
| 2231 | ret = print_tabs(session, nesting); |
| 2232 | if (ret) |
| 2233 | return ret; |
| 2234 | ret = lttng_metadata_printf(session, |
| 2235 | "string%s _%s;\n", |
| 2236 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
| 2237 | " { encoding = ASCII; }" : "", |
| 2238 | field->name); |
| 2239 | break; |
| 2240 | case atype_struct: |
| 2241 | ret = _lttng_struct_statedump(session, field, nesting); |
| 2242 | break; |
| 2243 | case atype_array_compound: |
| 2244 | ret = _lttng_array_compound_statedump(session, field, nesting); |
| 2245 | break; |
| 2246 | case atype_sequence_compound: |
| 2247 | ret = _lttng_sequence_compound_statedump(session, field, nesting); |
| 2248 | break; |
| 2249 | case atype_variant: |
| 2250 | ret = _lttng_variant_statedump(session, field, nesting); |
| 2251 | break; |
| 2252 | |
| 2253 | default: |
| 2254 | WARN_ON_ONCE(1); |
| 2255 | return -EINVAL; |
| 2256 | } |
| 2257 | return ret; |
| 2258 | } |
| 2259 | |
| 2260 | static |
| 2261 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
| 2262 | struct lttng_ctx *ctx) |
| 2263 | { |
| 2264 | int ret = 0; |
| 2265 | int i; |
| 2266 | |
| 2267 | if (!ctx) |
| 2268 | return 0; |
| 2269 | for (i = 0; i < ctx->nr_fields; i++) { |
| 2270 | const struct lttng_ctx_field *field = &ctx->fields[i]; |
| 2271 | |
| 2272 | ret = _lttng_field_statedump(session, &field->event_field, 2); |
| 2273 | if (ret) |
| 2274 | return ret; |
| 2275 | } |
| 2276 | return ret; |
| 2277 | } |
| 2278 | |
| 2279 | static |
| 2280 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
| 2281 | struct lttng_event *event) |
| 2282 | { |
| 2283 | const struct lttng_event_desc *desc = event->desc; |
| 2284 | int ret = 0; |
| 2285 | int i; |
| 2286 | |
| 2287 | for (i = 0; i < desc->nr_fields; i++) { |
| 2288 | const struct lttng_event_field *field = &desc->fields[i]; |
| 2289 | |
| 2290 | ret = _lttng_field_statedump(session, field, 2); |
| 2291 | if (ret) |
| 2292 | return ret; |
| 2293 | } |
| 2294 | return ret; |
| 2295 | } |
| 2296 | |
| 2297 | /* |
| 2298 | * Must be called with sessions_mutex held. |
| 2299 | */ |
| 2300 | static |
| 2301 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
| 2302 | struct lttng_channel *chan, |
| 2303 | struct lttng_event *event) |
| 2304 | { |
| 2305 | int ret = 0; |
| 2306 | |
| 2307 | if (event->metadata_dumped || !READ_ONCE(session->active)) |
| 2308 | return 0; |
| 2309 | if (chan->channel_type == METADATA_CHANNEL) |
| 2310 | return 0; |
| 2311 | |
| 2312 | ret = lttng_metadata_printf(session, |
| 2313 | "event {\n" |
| 2314 | " name = \"%s\";\n" |
| 2315 | " id = %u;\n" |
| 2316 | " stream_id = %u;\n", |
| 2317 | event->desc->name, |
| 2318 | event->id, |
| 2319 | event->chan->id); |
| 2320 | if (ret) |
| 2321 | goto end; |
| 2322 | |
| 2323 | if (event->ctx) { |
| 2324 | ret = lttng_metadata_printf(session, |
| 2325 | " context := struct {\n"); |
| 2326 | if (ret) |
| 2327 | goto end; |
| 2328 | } |
| 2329 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
| 2330 | if (ret) |
| 2331 | goto end; |
| 2332 | if (event->ctx) { |
| 2333 | ret = lttng_metadata_printf(session, |
| 2334 | " };\n"); |
| 2335 | if (ret) |
| 2336 | goto end; |
| 2337 | } |
| 2338 | |
| 2339 | ret = lttng_metadata_printf(session, |
| 2340 | " fields := struct {\n" |
| 2341 | ); |
| 2342 | if (ret) |
| 2343 | goto end; |
| 2344 | |
| 2345 | ret = _lttng_fields_metadata_statedump(session, event); |
| 2346 | if (ret) |
| 2347 | goto end; |
| 2348 | |
| 2349 | /* |
| 2350 | * LTTng space reservation can only reserve multiples of the |
| 2351 | * byte size. |
| 2352 | */ |
| 2353 | ret = lttng_metadata_printf(session, |
| 2354 | " };\n" |
| 2355 | "};\n\n"); |
| 2356 | if (ret) |
| 2357 | goto end; |
| 2358 | |
| 2359 | event->metadata_dumped = 1; |
| 2360 | end: |
| 2361 | return ret; |
| 2362 | |
| 2363 | } |
| 2364 | |
| 2365 | /* |
| 2366 | * Must be called with sessions_mutex held. |
| 2367 | */ |
| 2368 | static |
| 2369 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
| 2370 | struct lttng_channel *chan) |
| 2371 | { |
| 2372 | int ret = 0; |
| 2373 | |
| 2374 | if (chan->metadata_dumped || !READ_ONCE(session->active)) |
| 2375 | return 0; |
| 2376 | |
| 2377 | if (chan->channel_type == METADATA_CHANNEL) |
| 2378 | return 0; |
| 2379 | |
| 2380 | WARN_ON_ONCE(!chan->header_type); |
| 2381 | ret = lttng_metadata_printf(session, |
| 2382 | "stream {\n" |
| 2383 | " id = %u;\n" |
| 2384 | " event.header := %s;\n" |
| 2385 | " packet.context := struct packet_context;\n", |
| 2386 | chan->id, |
| 2387 | chan->header_type == 1 ? "struct event_header_compact" : |
| 2388 | "struct event_header_large"); |
| 2389 | if (ret) |
| 2390 | goto end; |
| 2391 | |
| 2392 | if (chan->ctx) { |
| 2393 | ret = lttng_metadata_printf(session, |
| 2394 | " event.context := struct {\n"); |
| 2395 | if (ret) |
| 2396 | goto end; |
| 2397 | } |
| 2398 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
| 2399 | if (ret) |
| 2400 | goto end; |
| 2401 | if (chan->ctx) { |
| 2402 | ret = lttng_metadata_printf(session, |
| 2403 | " };\n"); |
| 2404 | if (ret) |
| 2405 | goto end; |
| 2406 | } |
| 2407 | |
| 2408 | ret = lttng_metadata_printf(session, |
| 2409 | "};\n\n"); |
| 2410 | |
| 2411 | chan->metadata_dumped = 1; |
| 2412 | end: |
| 2413 | return ret; |
| 2414 | } |
| 2415 | |
| 2416 | /* |
| 2417 | * Must be called with sessions_mutex held. |
| 2418 | */ |
| 2419 | static |
| 2420 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
| 2421 | { |
| 2422 | return lttng_metadata_printf(session, |
| 2423 | "struct packet_context {\n" |
| 2424 | " uint64_clock_monotonic_t timestamp_begin;\n" |
| 2425 | " uint64_clock_monotonic_t timestamp_end;\n" |
| 2426 | " uint64_t content_size;\n" |
| 2427 | " uint64_t packet_size;\n" |
| 2428 | " uint64_t packet_seq_num;\n" |
| 2429 | " unsigned long events_discarded;\n" |
| 2430 | " uint32_t cpu_id;\n" |
| 2431 | "};\n\n" |
| 2432 | ); |
| 2433 | } |
| 2434 | |
| 2435 | /* |
| 2436 | * Compact header: |
| 2437 | * id: range: 0 - 30. |
| 2438 | * id 31 is reserved to indicate an extended header. |
| 2439 | * |
| 2440 | * Large header: |
| 2441 | * id: range: 0 - 65534. |
| 2442 | * id 65535 is reserved to indicate an extended header. |
| 2443 | * |
| 2444 | * Must be called with sessions_mutex held. |
| 2445 | */ |
| 2446 | static |
| 2447 | int _lttng_event_header_declare(struct lttng_session *session) |
| 2448 | { |
| 2449 | return lttng_metadata_printf(session, |
| 2450 | "struct event_header_compact {\n" |
| 2451 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" |
| 2452 | " variant <id> {\n" |
| 2453 | " struct {\n" |
| 2454 | " uint27_clock_monotonic_t timestamp;\n" |
| 2455 | " } compact;\n" |
| 2456 | " struct {\n" |
| 2457 | " uint32_t id;\n" |
| 2458 | " uint64_clock_monotonic_t timestamp;\n" |
| 2459 | " } extended;\n" |
| 2460 | " } v;\n" |
| 2461 | "} align(%u);\n" |
| 2462 | "\n" |
| 2463 | "struct event_header_large {\n" |
| 2464 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" |
| 2465 | " variant <id> {\n" |
| 2466 | " struct {\n" |
| 2467 | " uint32_clock_monotonic_t timestamp;\n" |
| 2468 | " } compact;\n" |
| 2469 | " struct {\n" |
| 2470 | " uint32_t id;\n" |
| 2471 | " uint64_clock_monotonic_t timestamp;\n" |
| 2472 | " } extended;\n" |
| 2473 | " } v;\n" |
| 2474 | "} align(%u);\n\n", |
| 2475 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 2476 | lttng_alignof(uint16_t) * CHAR_BIT |
| 2477 | ); |
| 2478 | } |
| 2479 | |
| 2480 | /* |
| 2481 | * Approximation of NTP time of day to clock monotonic correlation, |
| 2482 | * taken at start of trace. |
| 2483 | * Yes, this is only an approximation. Yes, we can (and will) do better |
| 2484 | * in future versions. |
| 2485 | * This function may return a negative offset. It may happen if the |
| 2486 | * system sets the REALTIME clock to 0 after boot. |
| 2487 | * |
| 2488 | * Use 64bit timespec on kernels that have it, this makes 32bit arch |
| 2489 | * y2038 compliant. |
| 2490 | */ |
| 2491 | static |
| 2492 | int64_t measure_clock_offset(void) |
| 2493 | { |
| 2494 | uint64_t monotonic_avg, monotonic[2], realtime; |
| 2495 | uint64_t tcf = trace_clock_freq(); |
| 2496 | int64_t offset; |
| 2497 | unsigned long flags; |
| 2498 | #ifdef LTTNG_KERNEL_HAS_TIMESPEC64 |
| 2499 | struct timespec64 rts = { 0, 0 }; |
| 2500 | #else |
| 2501 | struct timespec rts = { 0, 0 }; |
| 2502 | #endif |
| 2503 | |
| 2504 | /* Disable interrupts to increase correlation precision. */ |
| 2505 | local_irq_save(flags); |
| 2506 | monotonic[0] = trace_clock_read64(); |
| 2507 | #ifdef LTTNG_KERNEL_HAS_TIMESPEC64 |
| 2508 | ktime_get_real_ts64(&rts); |
| 2509 | #else |
| 2510 | getnstimeofday(&rts); |
| 2511 | #endif |
| 2512 | monotonic[1] = trace_clock_read64(); |
| 2513 | local_irq_restore(flags); |
| 2514 | |
| 2515 | monotonic_avg = (monotonic[0] + monotonic[1]) >> 1; |
| 2516 | realtime = (uint64_t) rts.tv_sec * tcf; |
| 2517 | if (tcf == NSEC_PER_SEC) { |
| 2518 | realtime += rts.tv_nsec; |
| 2519 | } else { |
| 2520 | uint64_t n = rts.tv_nsec * tcf; |
| 2521 | |
| 2522 | do_div(n, NSEC_PER_SEC); |
| 2523 | realtime += n; |
| 2524 | } |
| 2525 | offset = (int64_t) realtime - monotonic_avg; |
| 2526 | return offset; |
| 2527 | } |
| 2528 | |
| 2529 | static |
| 2530 | int print_escaped_ctf_string(struct lttng_session *session, const char *string) |
| 2531 | { |
| 2532 | int ret = 0; |
| 2533 | size_t i; |
| 2534 | char cur; |
| 2535 | |
| 2536 | i = 0; |
| 2537 | cur = string[i]; |
| 2538 | while (cur != '\0') { |
| 2539 | switch (cur) { |
| 2540 | case '\n': |
| 2541 | ret = lttng_metadata_printf(session, "%s", "\\n"); |
| 2542 | break; |
| 2543 | case '\\': |
| 2544 | case '"': |
| 2545 | ret = lttng_metadata_printf(session, "%c", '\\'); |
| 2546 | if (ret) |
| 2547 | goto error; |
| 2548 | /* We still print the current char */ |
| 2549 | /* Fallthrough */ |
| 2550 | default: |
| 2551 | ret = lttng_metadata_printf(session, "%c", cur); |
| 2552 | break; |
| 2553 | } |
| 2554 | |
| 2555 | if (ret) |
| 2556 | goto error; |
| 2557 | |
| 2558 | cur = string[++i]; |
| 2559 | } |
| 2560 | error: |
| 2561 | return ret; |
| 2562 | } |
| 2563 | |
| 2564 | static |
| 2565 | int print_metadata_escaped_field(struct lttng_session *session, const char *field, |
| 2566 | const char *field_value) |
| 2567 | { |
| 2568 | int ret; |
| 2569 | |
| 2570 | ret = lttng_metadata_printf(session, " %s = \"", field); |
| 2571 | if (ret) |
| 2572 | goto error; |
| 2573 | |
| 2574 | ret = print_escaped_ctf_string(session, field_value); |
| 2575 | if (ret) |
| 2576 | goto error; |
| 2577 | |
| 2578 | ret = lttng_metadata_printf(session, "\";\n"); |
| 2579 | |
| 2580 | error: |
| 2581 | return ret; |
| 2582 | } |
| 2583 | |
| 2584 | /* |
| 2585 | * Output metadata into this session's metadata buffers. |
| 2586 | * Must be called with sessions_mutex held. |
| 2587 | */ |
| 2588 | static |
| 2589 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
| 2590 | { |
| 2591 | unsigned char *uuid_c = session->uuid.b; |
| 2592 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
| 2593 | const char *product_uuid; |
| 2594 | struct lttng_channel *chan; |
| 2595 | struct lttng_event *event; |
| 2596 | int ret = 0; |
| 2597 | |
| 2598 | if (!READ_ONCE(session->active)) |
| 2599 | return 0; |
| 2600 | if (session->metadata_dumped) |
| 2601 | goto skip_session; |
| 2602 | |
| 2603 | snprintf(uuid_s, sizeof(uuid_s), |
| 2604 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
| 2605 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], |
| 2606 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], |
| 2607 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], |
| 2608 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); |
| 2609 | |
| 2610 | ret = lttng_metadata_printf(session, |
| 2611 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
| 2612 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" |
| 2613 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" |
| 2614 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" |
| 2615 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
| 2616 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
| 2617 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" |
| 2618 | "\n" |
| 2619 | "trace {\n" |
| 2620 | " major = %u;\n" |
| 2621 | " minor = %u;\n" |
| 2622 | " uuid = \"%s\";\n" |
| 2623 | " byte_order = %s;\n" |
| 2624 | " packet.header := struct {\n" |
| 2625 | " uint32_t magic;\n" |
| 2626 | " uint8_t uuid[16];\n" |
| 2627 | " uint32_t stream_id;\n" |
| 2628 | " uint64_t stream_instance_id;\n" |
| 2629 | " };\n" |
| 2630 | "};\n\n", |
| 2631 | lttng_alignof(uint8_t) * CHAR_BIT, |
| 2632 | lttng_alignof(uint16_t) * CHAR_BIT, |
| 2633 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 2634 | lttng_alignof(uint64_t) * CHAR_BIT, |
| 2635 | sizeof(unsigned long) * CHAR_BIT, |
| 2636 | lttng_alignof(unsigned long) * CHAR_BIT, |
| 2637 | CTF_SPEC_MAJOR, |
| 2638 | CTF_SPEC_MINOR, |
| 2639 | uuid_s, |
| 2640 | #if __BYTE_ORDER == __BIG_ENDIAN |
| 2641 | "be" |
| 2642 | #else |
| 2643 | "le" |
| 2644 | #endif |
| 2645 | ); |
| 2646 | if (ret) |
| 2647 | goto end; |
| 2648 | |
| 2649 | ret = lttng_metadata_printf(session, |
| 2650 | "env {\n" |
| 2651 | " hostname = \"%s\";\n" |
| 2652 | " domain = \"kernel\";\n" |
| 2653 | " sysname = \"%s\";\n" |
| 2654 | " kernel_release = \"%s\";\n" |
| 2655 | " kernel_version = \"%s\";\n" |
| 2656 | " tracer_name = \"lttng-modules\";\n" |
| 2657 | " tracer_major = %d;\n" |
| 2658 | " tracer_minor = %d;\n" |
| 2659 | " tracer_patchlevel = %d;\n" |
| 2660 | " trace_buffering_scheme = \"global\";\n", |
| 2661 | current->nsproxy->uts_ns->name.nodename, |
| 2662 | utsname()->sysname, |
| 2663 | utsname()->release, |
| 2664 | utsname()->version, |
| 2665 | LTTNG_MODULES_MAJOR_VERSION, |
| 2666 | LTTNG_MODULES_MINOR_VERSION, |
| 2667 | LTTNG_MODULES_PATCHLEVEL_VERSION |
| 2668 | ); |
| 2669 | if (ret) |
| 2670 | goto end; |
| 2671 | |
| 2672 | ret = print_metadata_escaped_field(session, "trace_name", session->name); |
| 2673 | if (ret) |
| 2674 | goto end; |
| 2675 | ret = print_metadata_escaped_field(session, "trace_creation_datetime", |
| 2676 | session->creation_time); |
| 2677 | if (ret) |
| 2678 | goto end; |
| 2679 | |
| 2680 | /* Add the product UUID to the 'env' section */ |
| 2681 | product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID); |
| 2682 | if (product_uuid) { |
| 2683 | ret = lttng_metadata_printf(session, |
| 2684 | " product_uuid = \"%s\";\n", |
| 2685 | product_uuid |
| 2686 | ); |
| 2687 | if (ret) |
| 2688 | goto end; |
| 2689 | } |
| 2690 | |
| 2691 | /* Close the 'env' section */ |
| 2692 | ret = lttng_metadata_printf(session, "};\n\n"); |
| 2693 | if (ret) |
| 2694 | goto end; |
| 2695 | |
| 2696 | ret = lttng_metadata_printf(session, |
| 2697 | "clock {\n" |
| 2698 | " name = \"%s\";\n", |
| 2699 | trace_clock_name() |
| 2700 | ); |
| 2701 | if (ret) |
| 2702 | goto end; |
| 2703 | |
| 2704 | if (!trace_clock_uuid(clock_uuid_s)) { |
| 2705 | ret = lttng_metadata_printf(session, |
| 2706 | " uuid = \"%s\";\n", |
| 2707 | clock_uuid_s |
| 2708 | ); |
| 2709 | if (ret) |
| 2710 | goto end; |
| 2711 | } |
| 2712 | |
| 2713 | ret = lttng_metadata_printf(session, |
| 2714 | " description = \"%s\";\n" |
| 2715 | " freq = %llu; /* Frequency, in Hz */\n" |
| 2716 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" |
| 2717 | " offset = %lld;\n" |
| 2718 | "};\n\n", |
| 2719 | trace_clock_description(), |
| 2720 | (unsigned long long) trace_clock_freq(), |
| 2721 | (long long) measure_clock_offset() |
| 2722 | ); |
| 2723 | if (ret) |
| 2724 | goto end; |
| 2725 | |
| 2726 | ret = lttng_metadata_printf(session, |
| 2727 | "typealias integer {\n" |
| 2728 | " size = 27; align = 1; signed = false;\n" |
| 2729 | " map = clock.%s.value;\n" |
| 2730 | "} := uint27_clock_monotonic_t;\n" |
| 2731 | "\n" |
| 2732 | "typealias integer {\n" |
| 2733 | " size = 32; align = %u; signed = false;\n" |
| 2734 | " map = clock.%s.value;\n" |
| 2735 | "} := uint32_clock_monotonic_t;\n" |
| 2736 | "\n" |
| 2737 | "typealias integer {\n" |
| 2738 | " size = 64; align = %u; signed = false;\n" |
| 2739 | " map = clock.%s.value;\n" |
| 2740 | "} := uint64_clock_monotonic_t;\n\n", |
| 2741 | trace_clock_name(), |
| 2742 | lttng_alignof(uint32_t) * CHAR_BIT, |
| 2743 | trace_clock_name(), |
| 2744 | lttng_alignof(uint64_t) * CHAR_BIT, |
| 2745 | trace_clock_name() |
| 2746 | ); |
| 2747 | if (ret) |
| 2748 | goto end; |
| 2749 | |
| 2750 | ret = _lttng_stream_packet_context_declare(session); |
| 2751 | if (ret) |
| 2752 | goto end; |
| 2753 | |
| 2754 | ret = _lttng_event_header_declare(session); |
| 2755 | if (ret) |
| 2756 | goto end; |
| 2757 | |
| 2758 | skip_session: |
| 2759 | list_for_each_entry(chan, &session->chan, list) { |
| 2760 | ret = _lttng_channel_metadata_statedump(session, chan); |
| 2761 | if (ret) |
| 2762 | goto end; |
| 2763 | } |
| 2764 | |
| 2765 | list_for_each_entry(event, &session->events, list) { |
| 2766 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
| 2767 | if (ret) |
| 2768 | goto end; |
| 2769 | } |
| 2770 | session->metadata_dumped = 1; |
| 2771 | end: |
| 2772 | return ret; |
| 2773 | } |
| 2774 | |
| 2775 | /** |
| 2776 | * lttng_transport_register - LTT transport registration |
| 2777 | * @transport: transport structure |
| 2778 | * |
| 2779 | * Registers a transport which can be used as output to extract the data out of |
| 2780 | * LTTng. The module calling this registration function must ensure that no |
| 2781 | * trap-inducing code will be executed by the transport functions. E.g. |
| 2782 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory |
| 2783 | * is made visible to the transport function. This registration acts as a |
| 2784 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory |
| 2785 | * after its registration must it synchronize the TLBs. |
| 2786 | */ |
| 2787 | void lttng_transport_register(struct lttng_transport *transport) |
| 2788 | { |
| 2789 | /* |
| 2790 | * Make sure no page fault can be triggered by the module about to be |
| 2791 | * registered. We deal with this here so we don't have to call |
| 2792 | * vmalloc_sync_all() in each module's init. |
| 2793 | */ |
| 2794 | wrapper_vmalloc_sync_all(); |
| 2795 | |
| 2796 | mutex_lock(&sessions_mutex); |
| 2797 | list_add_tail(&transport->node, <tng_transport_list); |
| 2798 | mutex_unlock(&sessions_mutex); |
| 2799 | } |
| 2800 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
| 2801 | |
| 2802 | /** |
| 2803 | * lttng_transport_unregister - LTT transport unregistration |
| 2804 | * @transport: transport structure |
| 2805 | */ |
| 2806 | void lttng_transport_unregister(struct lttng_transport *transport) |
| 2807 | { |
| 2808 | mutex_lock(&sessions_mutex); |
| 2809 | list_del(&transport->node); |
| 2810 | mutex_unlock(&sessions_mutex); |
| 2811 | } |
| 2812 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
| 2813 | |
| 2814 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) |
| 2815 | |
| 2816 | enum cpuhp_state lttng_hp_prepare; |
| 2817 | enum cpuhp_state lttng_hp_online; |
| 2818 | |
| 2819 | static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node) |
| 2820 | { |
| 2821 | struct lttng_cpuhp_node *lttng_node; |
| 2822 | |
| 2823 | lttng_node = container_of(node, struct lttng_cpuhp_node, node); |
| 2824 | switch (lttng_node->component) { |
| 2825 | case LTTNG_RING_BUFFER_FRONTEND: |
| 2826 | return 0; |
| 2827 | case LTTNG_RING_BUFFER_BACKEND: |
| 2828 | return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node); |
| 2829 | case LTTNG_RING_BUFFER_ITER: |
| 2830 | return 0; |
| 2831 | case LTTNG_CONTEXT_PERF_COUNTERS: |
| 2832 | return 0; |
| 2833 | default: |
| 2834 | return -EINVAL; |
| 2835 | } |
| 2836 | } |
| 2837 | |
| 2838 | static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node) |
| 2839 | { |
| 2840 | struct lttng_cpuhp_node *lttng_node; |
| 2841 | |
| 2842 | lttng_node = container_of(node, struct lttng_cpuhp_node, node); |
| 2843 | switch (lttng_node->component) { |
| 2844 | case LTTNG_RING_BUFFER_FRONTEND: |
| 2845 | return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node); |
| 2846 | case LTTNG_RING_BUFFER_BACKEND: |
| 2847 | return 0; |
| 2848 | case LTTNG_RING_BUFFER_ITER: |
| 2849 | return 0; |
| 2850 | case LTTNG_CONTEXT_PERF_COUNTERS: |
| 2851 | return lttng_cpuhp_perf_counter_dead(cpu, lttng_node); |
| 2852 | default: |
| 2853 | return -EINVAL; |
| 2854 | } |
| 2855 | } |
| 2856 | |
| 2857 | static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node) |
| 2858 | { |
| 2859 | struct lttng_cpuhp_node *lttng_node; |
| 2860 | |
| 2861 | lttng_node = container_of(node, struct lttng_cpuhp_node, node); |
| 2862 | switch (lttng_node->component) { |
| 2863 | case LTTNG_RING_BUFFER_FRONTEND: |
| 2864 | return lttng_cpuhp_rb_frontend_online(cpu, lttng_node); |
| 2865 | case LTTNG_RING_BUFFER_BACKEND: |
| 2866 | return 0; |
| 2867 | case LTTNG_RING_BUFFER_ITER: |
| 2868 | return lttng_cpuhp_rb_iter_online(cpu, lttng_node); |
| 2869 | case LTTNG_CONTEXT_PERF_COUNTERS: |
| 2870 | return lttng_cpuhp_perf_counter_online(cpu, lttng_node); |
| 2871 | default: |
| 2872 | return -EINVAL; |
| 2873 | } |
| 2874 | } |
| 2875 | |
| 2876 | static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node) |
| 2877 | { |
| 2878 | struct lttng_cpuhp_node *lttng_node; |
| 2879 | |
| 2880 | lttng_node = container_of(node, struct lttng_cpuhp_node, node); |
| 2881 | switch (lttng_node->component) { |
| 2882 | case LTTNG_RING_BUFFER_FRONTEND: |
| 2883 | return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node); |
| 2884 | case LTTNG_RING_BUFFER_BACKEND: |
| 2885 | return 0; |
| 2886 | case LTTNG_RING_BUFFER_ITER: |
| 2887 | return 0; |
| 2888 | case LTTNG_CONTEXT_PERF_COUNTERS: |
| 2889 | return 0; |
| 2890 | default: |
| 2891 | return -EINVAL; |
| 2892 | } |
| 2893 | } |
| 2894 | |
| 2895 | static int __init lttng_init_cpu_hotplug(void) |
| 2896 | { |
| 2897 | int ret; |
| 2898 | |
| 2899 | ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare", |
| 2900 | lttng_hotplug_prepare, |
| 2901 | lttng_hotplug_dead); |
| 2902 | if (ret < 0) { |
| 2903 | return ret; |
| 2904 | } |
| 2905 | lttng_hp_prepare = ret; |
| 2906 | lttng_rb_set_hp_prepare(ret); |
| 2907 | |
| 2908 | ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online", |
| 2909 | lttng_hotplug_online, |
| 2910 | lttng_hotplug_offline); |
| 2911 | if (ret < 0) { |
| 2912 | cpuhp_remove_multi_state(lttng_hp_prepare); |
| 2913 | lttng_hp_prepare = 0; |
| 2914 | return ret; |
| 2915 | } |
| 2916 | lttng_hp_online = ret; |
| 2917 | lttng_rb_set_hp_online(ret); |
| 2918 | |
| 2919 | return 0; |
| 2920 | } |
| 2921 | |
| 2922 | static void __exit lttng_exit_cpu_hotplug(void) |
| 2923 | { |
| 2924 | lttng_rb_set_hp_online(0); |
| 2925 | cpuhp_remove_multi_state(lttng_hp_online); |
| 2926 | lttng_rb_set_hp_prepare(0); |
| 2927 | cpuhp_remove_multi_state(lttng_hp_prepare); |
| 2928 | } |
| 2929 | |
| 2930 | #else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */ |
| 2931 | static int lttng_init_cpu_hotplug(void) |
| 2932 | { |
| 2933 | return 0; |
| 2934 | } |
| 2935 | static void lttng_exit_cpu_hotplug(void) |
| 2936 | { |
| 2937 | } |
| 2938 | #endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */ |
| 2939 | |
| 2940 | |
| 2941 | static int __init lttng_events_init(void) |
| 2942 | { |
| 2943 | int ret; |
| 2944 | |
| 2945 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
| 2946 | if (ret) |
| 2947 | return ret; |
| 2948 | ret = wrapper_get_pfnblock_flags_mask_init(); |
| 2949 | if (ret) |
| 2950 | return ret; |
| 2951 | ret = wrapper_get_pageblock_flags_mask_init(); |
| 2952 | if (ret) |
| 2953 | return ret; |
| 2954 | ret = lttng_probes_init(); |
| 2955 | if (ret) |
| 2956 | return ret; |
| 2957 | ret = lttng_context_init(); |
| 2958 | if (ret) |
| 2959 | return ret; |
| 2960 | ret = lttng_tracepoint_init(); |
| 2961 | if (ret) |
| 2962 | goto error_tp; |
| 2963 | event_cache = KMEM_CACHE(lttng_event, 0); |
| 2964 | if (!event_cache) { |
| 2965 | ret = -ENOMEM; |
| 2966 | goto error_kmem; |
| 2967 | } |
| 2968 | ret = lttng_abi_init(); |
| 2969 | if (ret) |
| 2970 | goto error_abi; |
| 2971 | ret = lttng_logger_init(); |
| 2972 | if (ret) |
| 2973 | goto error_logger; |
| 2974 | ret = lttng_init_cpu_hotplug(); |
| 2975 | if (ret) |
| 2976 | goto error_hotplug; |
| 2977 | printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n", |
| 2978 | __stringify(LTTNG_MODULES_MAJOR_VERSION), |
| 2979 | __stringify(LTTNG_MODULES_MINOR_VERSION), |
| 2980 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION), |
| 2981 | LTTNG_MODULES_EXTRAVERSION, |
| 2982 | LTTNG_VERSION_NAME, |
| 2983 | #ifdef LTTNG_EXTRA_VERSION_GIT |
| 2984 | LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT, |
| 2985 | #else |
| 2986 | "", |
| 2987 | #endif |
| 2988 | #ifdef LTTNG_EXTRA_VERSION_NAME |
| 2989 | LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME); |
| 2990 | #else |
| 2991 | ""); |
| 2992 | #endif |
| 2993 | return 0; |
| 2994 | |
| 2995 | error_hotplug: |
| 2996 | lttng_logger_exit(); |
| 2997 | error_logger: |
| 2998 | lttng_abi_exit(); |
| 2999 | error_abi: |
| 3000 | kmem_cache_destroy(event_cache); |
| 3001 | error_kmem: |
| 3002 | lttng_tracepoint_exit(); |
| 3003 | error_tp: |
| 3004 | lttng_context_exit(); |
| 3005 | printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n", |
| 3006 | __stringify(LTTNG_MODULES_MAJOR_VERSION), |
| 3007 | __stringify(LTTNG_MODULES_MINOR_VERSION), |
| 3008 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION), |
| 3009 | LTTNG_MODULES_EXTRAVERSION, |
| 3010 | LTTNG_VERSION_NAME, |
| 3011 | #ifdef LTTNG_EXTRA_VERSION_GIT |
| 3012 | LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT, |
| 3013 | #else |
| 3014 | "", |
| 3015 | #endif |
| 3016 | #ifdef LTTNG_EXTRA_VERSION_NAME |
| 3017 | LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME); |
| 3018 | #else |
| 3019 | ""); |
| 3020 | #endif |
| 3021 | return ret; |
| 3022 | } |
| 3023 | |
| 3024 | module_init(lttng_events_init); |
| 3025 | |
| 3026 | static void __exit lttng_events_exit(void) |
| 3027 | { |
| 3028 | struct lttng_session *session, *tmpsession; |
| 3029 | |
| 3030 | lttng_exit_cpu_hotplug(); |
| 3031 | lttng_logger_exit(); |
| 3032 | lttng_abi_exit(); |
| 3033 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
| 3034 | lttng_session_destroy(session); |
| 3035 | kmem_cache_destroy(event_cache); |
| 3036 | lttng_tracepoint_exit(); |
| 3037 | lttng_context_exit(); |
| 3038 | printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n", |
| 3039 | __stringify(LTTNG_MODULES_MAJOR_VERSION), |
| 3040 | __stringify(LTTNG_MODULES_MINOR_VERSION), |
| 3041 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION), |
| 3042 | LTTNG_MODULES_EXTRAVERSION, |
| 3043 | LTTNG_VERSION_NAME, |
| 3044 | #ifdef LTTNG_EXTRA_VERSION_GIT |
| 3045 | LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT, |
| 3046 | #else |
| 3047 | "", |
| 3048 | #endif |
| 3049 | #ifdef LTTNG_EXTRA_VERSION_NAME |
| 3050 | LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME); |
| 3051 | #else |
| 3052 | ""); |
| 3053 | #endif |
| 3054 | } |
| 3055 | |
| 3056 | module_exit(lttng_events_exit); |
| 3057 | |
| 3058 | #include "extra_version/patches.i" |
| 3059 | #ifdef LTTNG_EXTRA_VERSION_GIT |
| 3060 | MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT); |
| 3061 | #endif |
| 3062 | #ifdef LTTNG_EXTRA_VERSION_NAME |
| 3063 | MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME); |
| 3064 | #endif |
| 3065 | MODULE_LICENSE("GPL and additional rights"); |
| 3066 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); |
| 3067 | MODULE_DESCRIPTION("LTTng tracer"); |
| 3068 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
| 3069 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." |
| 3070 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
| 3071 | LTTNG_MODULES_EXTRAVERSION); |