Commit | Line | Data |
---|---|---|
8020ceb5 MD |
1 | /* |
2 | * ltt-events.c | |
3 | * | |
4 | * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * Holds LTTng per-session event registry. | |
7 | * | |
8 | * Dual LGPL v2.1/GPL v2 license. | |
9 | */ | |
10 | ||
b5234c06 MD |
11 | #define _GNU_SOURCE |
12 | #include <stdio.h> | |
8a98a75d | 13 | #include <endian.h> |
b5234c06 | 14 | #include <urcu/list.h> |
8165c8da | 15 | #include <urcu/hlist.h> |
b5234c06 MD |
16 | #include <pthread.h> |
17 | #include <urcu-bp.h> | |
18 | #include <urcu/compiler.h> | |
19 | #include <urcu/uatomic.h> | |
20 | #include <uuid/uuid.h> | |
21 | #include <ust/tracepoint.h> | |
22 | #include <errno.h> | |
f4681817 MD |
23 | #include <sys/shm.h> |
24 | #include <sys/ipc.h> | |
25 | #include <ust/lttng-events.h> | |
1dbfff0c | 26 | #include <ust/usterr-signal-safe.h> |
b5234c06 | 27 | #include "ust/core.h" |
8020ceb5 | 28 | #include "ltt-tracer.h" |
8165c8da | 29 | #include "ltt-tracer-core.h" |
b5234c06 | 30 | #include "ust/wait.h" |
8d8a24c8 | 31 | #include "../libringbuffer/shm.h" |
8020ceb5 | 32 | |
8165c8da MD |
33 | typedef u32 uint32_t; |
34 | #include <ust/kcompat/jhash.h> | |
35 | ||
36 | /* | |
37 | * The sessions mutex is the centralized mutex across UST tracing | |
17dfb34b MD |
38 | * control and probe registration. All operations within this file are |
39 | * called by the communication thread, under ust_lock protection. | |
8165c8da MD |
40 | */ |
41 | static DEFINE_MUTEX(sessions_mutex); | |
42 | ||
17dfb34b | 43 | void ust_lock(void) |
8165c8da MD |
44 | { |
45 | pthread_mutex_lock(&sessions_mutex); | |
46 | } | |
47 | ||
17dfb34b | 48 | void ust_unlock(void) |
8165c8da MD |
49 | { |
50 | pthread_mutex_unlock(&sessions_mutex); | |
51 | } | |
52 | ||
b5234c06 MD |
53 | static CDS_LIST_HEAD(sessions); |
54 | static CDS_LIST_HEAD(ltt_transport_list); | |
8165c8da MD |
55 | |
56 | /* | |
57 | * Pending probes hash table, containing the registered ltt events for | |
58 | * which tracepoint probes are still missing. Protected by the sessions | |
59 | * mutex. | |
60 | */ | |
61 | #define PENDING_PROBE_HASH_BITS 6 | |
62 | #define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS) | |
63 | static struct cds_hlist_head pending_probe_table[PENDING_PROBE_HASH_SIZE]; | |
64 | ||
65 | struct ust_pending_probe { | |
66 | struct ltt_event *event; | |
67 | struct cds_hlist_node node; | |
68 | char name[]; | |
69 | }; | |
8020ceb5 MD |
70 | |
71 | static void _ltt_event_destroy(struct ltt_event *event); | |
72 | static void _ltt_channel_destroy(struct ltt_channel *chan); | |
73 | static int _ltt_event_unregister(struct ltt_event *event); | |
74 | static | |
75 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
76 | struct ltt_channel *chan, | |
77 | struct ltt_event *event); | |
78 | static | |
79 | int _ltt_session_metadata_statedump(struct ltt_session *session); | |
80 | ||
8165c8da MD |
81 | /* |
82 | * called at event creation if probe is missing. | |
83 | * called with session mutex held. | |
84 | */ | |
85 | static | |
86 | int add_pending_probe(struct ltt_event *event, const char *name) | |
87 | { | |
88 | struct cds_hlist_head *head; | |
8165c8da MD |
89 | struct ust_pending_probe *e; |
90 | size_t name_len = strlen(name) + 1; | |
91 | u32 hash = jhash(name, name_len - 1, 0); | |
92 | ||
93 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; | |
94 | e = zmalloc(sizeof(struct ust_pending_probe) + name_len); | |
95 | if (!e) | |
96 | return -ENOMEM; | |
97 | memcpy(&e->name[0], name, name_len); | |
98 | cds_hlist_add_head(&e->node, head); | |
99 | e->event = event; | |
100 | event->pending_probe = e; | |
101 | return 0; | |
102 | } | |
103 | ||
104 | /* | |
105 | * remove a pending probe. called when at event teardown and when an | |
106 | * event is fixed (probe is loaded). | |
107 | * called with session mutex held. | |
108 | */ | |
109 | static | |
110 | void remove_pending_probe(struct ust_pending_probe *e) | |
111 | { | |
112 | if (!e) | |
113 | return; | |
114 | cds_hlist_del(&e->node); | |
115 | free(e); | |
116 | } | |
117 | ||
118 | /* | |
119 | * Called at library load: connect the probe on the events pending on | |
120 | * probe load. | |
121 | * called with session mutex held. | |
122 | */ | |
123 | int pending_probe_fix_events(const struct lttng_event_desc *desc) | |
124 | { | |
125 | struct cds_hlist_head *head; | |
126 | struct cds_hlist_node *node, *p; | |
127 | struct ust_pending_probe *e; | |
128 | const char *name = desc->name; | |
129 | size_t name_len = strlen(name) + 1; | |
130 | u32 hash = jhash(name, name_len - 1, 0); | |
131 | int ret = 0; | |
132 | ||
133 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; | |
134 | cds_hlist_for_each_entry_safe(e, node, p, head, node) { | |
135 | struct ltt_event *event; | |
136 | struct ltt_channel *chan; | |
137 | ||
138 | if (strcmp(name, e->name)) | |
139 | continue; | |
140 | event = e->event; | |
141 | chan = event->chan; | |
142 | assert(!event->desc); | |
143 | event->desc = desc; | |
144 | event->pending_probe = NULL; | |
145 | remove_pending_probe(e); | |
146 | ret |= __tracepoint_probe_register(name, | |
147 | event->desc->probe_callback, | |
148 | event); | |
149 | ret |= _ltt_event_metadata_statedump(chan->session, chan, | |
150 | event); | |
151 | } | |
152 | return ret; | |
153 | } | |
154 | ||
8020ceb5 MD |
155 | void synchronize_trace(void) |
156 | { | |
8020ceb5 | 157 | synchronize_rcu(); |
8020ceb5 MD |
158 | } |
159 | ||
160 | struct ltt_session *ltt_session_create(void) | |
161 | { | |
162 | struct ltt_session *session; | |
163 | ||
b5234c06 | 164 | session = zmalloc(sizeof(struct ltt_session)); |
8020ceb5 MD |
165 | if (!session) |
166 | return NULL; | |
b5234c06 MD |
167 | CDS_INIT_LIST_HEAD(&session->chan); |
168 | CDS_INIT_LIST_HEAD(&session->events); | |
169 | uuid_generate(session->uuid); | |
170 | cds_list_add(&session->list, &sessions); | |
8020ceb5 MD |
171 | return session; |
172 | } | |
173 | ||
174 | void ltt_session_destroy(struct ltt_session *session) | |
175 | { | |
176 | struct ltt_channel *chan, *tmpchan; | |
177 | struct ltt_event *event, *tmpevent; | |
178 | int ret; | |
179 | ||
b5234c06 MD |
180 | CMM_ACCESS_ONCE(session->active) = 0; |
181 | cds_list_for_each_entry(event, &session->events, list) { | |
8020ceb5 MD |
182 | ret = _ltt_event_unregister(event); |
183 | WARN_ON(ret); | |
184 | } | |
185 | synchronize_trace(); /* Wait for in-flight events to complete */ | |
b5234c06 | 186 | cds_list_for_each_entry_safe(event, tmpevent, &session->events, list) |
8020ceb5 | 187 | _ltt_event_destroy(event); |
b5234c06 | 188 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list) |
8020ceb5 | 189 | _ltt_channel_destroy(chan); |
b5234c06 | 190 | cds_list_del(&session->list); |
b5234c06 | 191 | free(session); |
8020ceb5 MD |
192 | } |
193 | ||
976fe9ea | 194 | int ltt_session_enable(struct ltt_session *session) |
8020ceb5 MD |
195 | { |
196 | int ret = 0; | |
197 | struct ltt_channel *chan; | |
198 | ||
8020ceb5 MD |
199 | if (session->active) { |
200 | ret = -EBUSY; | |
201 | goto end; | |
202 | } | |
203 | ||
204 | /* | |
205 | * Snapshot the number of events per channel to know the type of header | |
206 | * we need to use. | |
207 | */ | |
b5234c06 | 208 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
209 | if (chan->header_type) |
210 | continue; /* don't change it if session stop/restart */ | |
211 | if (chan->free_event_id < 31) | |
212 | chan->header_type = 1; /* compact */ | |
213 | else | |
214 | chan->header_type = 2; /* large */ | |
215 | } | |
216 | ||
b5234c06 MD |
217 | CMM_ACCESS_ONCE(session->active) = 1; |
218 | CMM_ACCESS_ONCE(session->been_active) = 1; | |
8020ceb5 | 219 | ret = _ltt_session_metadata_statedump(session); |
4b4de73e | 220 | if (ret) |
b5234c06 | 221 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 222 | end: |
8020ceb5 MD |
223 | return ret; |
224 | } | |
225 | ||
976fe9ea | 226 | int ltt_session_disable(struct ltt_session *session) |
8020ceb5 MD |
227 | { |
228 | int ret = 0; | |
229 | ||
8020ceb5 MD |
230 | if (!session->active) { |
231 | ret = -EBUSY; | |
232 | goto end; | |
233 | } | |
b5234c06 | 234 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 235 | end: |
8020ceb5 MD |
236 | return ret; |
237 | } | |
238 | ||
976fe9ea MD |
239 | int ltt_channel_enable(struct ltt_channel *channel) |
240 | { | |
241 | int old; | |
242 | ||
9beb36ba MD |
243 | if (channel == channel->session->metadata) |
244 | return -EPERM; | |
b5234c06 | 245 | old = uatomic_xchg(&channel->enabled, 1); |
976fe9ea MD |
246 | if (old) |
247 | return -EEXIST; | |
248 | return 0; | |
249 | } | |
250 | ||
251 | int ltt_channel_disable(struct ltt_channel *channel) | |
252 | { | |
253 | int old; | |
254 | ||
9beb36ba MD |
255 | if (channel == channel->session->metadata) |
256 | return -EPERM; | |
b5234c06 | 257 | old = uatomic_xchg(&channel->enabled, 0); |
976fe9ea MD |
258 | if (!old) |
259 | return -EEXIST; | |
260 | return 0; | |
261 | } | |
262 | ||
263 | int ltt_event_enable(struct ltt_event *event) | |
264 | { | |
265 | int old; | |
266 | ||
9beb36ba MD |
267 | if (event->chan == event->chan->session->metadata) |
268 | return -EPERM; | |
b5234c06 | 269 | old = uatomic_xchg(&event->enabled, 1); |
976fe9ea MD |
270 | if (old) |
271 | return -EEXIST; | |
272 | return 0; | |
273 | } | |
274 | ||
275 | int ltt_event_disable(struct ltt_event *event) | |
276 | { | |
277 | int old; | |
278 | ||
9beb36ba MD |
279 | if (event->chan == event->chan->session->metadata) |
280 | return -EPERM; | |
b5234c06 | 281 | old = uatomic_xchg(&event->enabled, 0); |
976fe9ea MD |
282 | if (!old) |
283 | return -EEXIST; | |
284 | return 0; | |
285 | } | |
286 | ||
8020ceb5 MD |
287 | static struct ltt_transport *ltt_transport_find(const char *name) |
288 | { | |
289 | struct ltt_transport *transport; | |
290 | ||
b5234c06 | 291 | cds_list_for_each_entry(transport, <t_transport_list, node) { |
8020ceb5 MD |
292 | if (!strcmp(transport->name, name)) |
293 | return transport; | |
294 | } | |
295 | return NULL; | |
296 | } | |
297 | ||
298 | struct ltt_channel *ltt_channel_create(struct ltt_session *session, | |
299 | const char *transport_name, | |
300 | void *buf_addr, | |
301 | size_t subbuf_size, size_t num_subbuf, | |
302 | unsigned int switch_timer_interval, | |
193183fb MD |
303 | unsigned int read_timer_interval, |
304 | int *shm_fd, int *wait_fd, | |
305 | uint64_t *memory_map_size) | |
8020ceb5 MD |
306 | { |
307 | struct ltt_channel *chan; | |
308 | struct ltt_transport *transport; | |
309 | ||
8020ceb5 MD |
310 | if (session->been_active) |
311 | goto active; /* Refuse to add channel to active session */ | |
312 | transport = ltt_transport_find(transport_name); | |
313 | if (!transport) { | |
b5234c06 | 314 | DBG("LTTng transport %s not found\n", |
8020ceb5 MD |
315 | transport_name); |
316 | goto notransport; | |
317 | } | |
b5234c06 | 318 | chan = zmalloc(sizeof(struct ltt_channel)); |
8020ceb5 MD |
319 | if (!chan) |
320 | goto nomem; | |
321 | chan->session = session; | |
322 | chan->id = session->free_chan_id++; | |
323 | /* | |
324 | * Note: the channel creation op already writes into the packet | |
325 | * headers. Therefore the "chan" information used as input | |
326 | * should be already accessible. | |
327 | */ | |
1d498196 | 328 | transport->ops.channel_create("[lttng]", chan, buf_addr, |
8020ceb5 | 329 | subbuf_size, num_subbuf, switch_timer_interval, |
193183fb MD |
330 | read_timer_interval, shm_fd, wait_fd, |
331 | memory_map_size); | |
8020ceb5 MD |
332 | if (!chan->chan) |
333 | goto create_error; | |
976fe9ea | 334 | chan->enabled = 1; |
8020ceb5 | 335 | chan->ops = &transport->ops; |
b5234c06 | 336 | cds_list_add(&chan->list, &session->chan); |
8020ceb5 MD |
337 | return chan; |
338 | ||
339 | create_error: | |
b5234c06 | 340 | free(chan); |
8020ceb5 MD |
341 | nomem: |
342 | notransport: | |
343 | active: | |
8020ceb5 MD |
344 | return NULL; |
345 | } | |
346 | ||
347 | /* | |
348 | * Only used internally at session destruction. | |
349 | */ | |
350 | static | |
351 | void _ltt_channel_destroy(struct ltt_channel *chan) | |
352 | { | |
1d498196 | 353 | chan->ops->channel_destroy(chan); |
b5234c06 | 354 | cds_list_del(&chan->list); |
8020ceb5 | 355 | lttng_destroy_context(chan->ctx); |
b5234c06 | 356 | free(chan); |
8020ceb5 MD |
357 | } |
358 | ||
359 | /* | |
360 | * Supports event creation while tracing session is active. | |
361 | */ | |
362 | struct ltt_event *ltt_event_create(struct ltt_channel *chan, | |
b5234c06 | 363 | struct lttng_ust_event *event_param, |
8020ceb5 MD |
364 | void *filter) |
365 | { | |
366 | struct ltt_event *event; | |
367 | int ret; | |
368 | ||
8165c8da | 369 | if (chan->used_event_id == -1UL) |
8020ceb5 MD |
370 | goto full; |
371 | /* | |
372 | * This is O(n^2) (for each event, the loop is called at event | |
373 | * creation). Might require a hash if we have lots of events. | |
374 | */ | |
b5234c06 | 375 | cds_list_for_each_entry(event, &chan->session->events, list) |
8165c8da | 376 | if (event->desc && !strcmp(event->desc->name, event_param->name)) |
8020ceb5 | 377 | goto exist; |
b5234c06 | 378 | event = zmalloc(sizeof(struct ltt_event)); |
8020ceb5 MD |
379 | if (!event) |
380 | goto cache_error; | |
381 | event->chan = chan; | |
382 | event->filter = filter; | |
8165c8da MD |
383 | /* |
384 | * used_event_id counts the maximum number of event IDs that can | |
385 | * register if all probes register. | |
386 | */ | |
387 | chan->used_event_id++; | |
976fe9ea | 388 | event->enabled = 1; |
8020ceb5 MD |
389 | event->instrumentation = event_param->instrumentation; |
390 | /* Populate ltt_event structure before tracepoint registration. */ | |
b5234c06 | 391 | cmm_smp_wmb(); |
8020ceb5 | 392 | switch (event_param->instrumentation) { |
b5234c06 | 393 | case LTTNG_UST_TRACEPOINT: |
8020ceb5 | 394 | event->desc = ltt_event_get(event_param->name); |
8165c8da MD |
395 | if (event->desc) { |
396 | ret = __tracepoint_probe_register(event_param->name, | |
397 | event->desc->probe_callback, | |
398 | event); | |
399 | if (ret) | |
400 | goto register_error; | |
401 | event->id = chan->free_event_id++; | |
402 | } else { | |
403 | /* | |
404 | * If the probe is not present, event->desc stays NULL, | |
405 | * waiting for the probe to register, and the event->id | |
406 | * stays unallocated. | |
407 | */ | |
408 | ret = add_pending_probe(event, event_param->name); | |
409 | if (ret) | |
410 | goto add_pending_error; | |
411 | } | |
8020ceb5 | 412 | break; |
8020ceb5 MD |
413 | default: |
414 | WARN_ON_ONCE(1); | |
415 | } | |
8165c8da MD |
416 | if (event->desc) { |
417 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); | |
418 | if (ret) | |
419 | goto statedump_error; | |
420 | } | |
b5234c06 | 421 | cds_list_add(&event->list, &chan->session->events); |
8020ceb5 MD |
422 | return event; |
423 | ||
424 | statedump_error: | |
8165c8da MD |
425 | if (event->desc) { |
426 | WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name, | |
427 | event->desc->probe_callback, | |
428 | event)); | |
429 | ltt_event_put(event->desc); | |
430 | } | |
431 | add_pending_error: | |
8020ceb5 | 432 | register_error: |
b5234c06 | 433 | free(event); |
8020ceb5 MD |
434 | cache_error: |
435 | exist: | |
436 | full: | |
8020ceb5 MD |
437 | return NULL; |
438 | } | |
439 | ||
440 | /* | |
441 | * Only used internally at session destruction. | |
442 | */ | |
443 | int _ltt_event_unregister(struct ltt_event *event) | |
444 | { | |
445 | int ret = -EINVAL; | |
446 | ||
447 | switch (event->instrumentation) { | |
b5234c06 | 448 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
449 | if (event->desc) { |
450 | ret = __tracepoint_probe_unregister(event->desc->name, | |
451 | event->desc->probe_callback, | |
452 | event); | |
453 | if (ret) | |
454 | return ret; | |
455 | } else { | |
456 | remove_pending_probe(event->pending_probe); | |
457 | ret = 0; | |
458 | } | |
8020ceb5 | 459 | break; |
8020ceb5 MD |
460 | default: |
461 | WARN_ON_ONCE(1); | |
462 | } | |
463 | return ret; | |
464 | } | |
465 | ||
466 | /* | |
467 | * Only used internally at session destruction. | |
468 | */ | |
469 | static | |
470 | void _ltt_event_destroy(struct ltt_event *event) | |
471 | { | |
472 | switch (event->instrumentation) { | |
b5234c06 | 473 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
474 | if (event->desc) { |
475 | ltt_event_put(event->desc); | |
476 | } | |
8020ceb5 | 477 | break; |
8020ceb5 MD |
478 | default: |
479 | WARN_ON_ONCE(1); | |
480 | } | |
b5234c06 | 481 | cds_list_del(&event->list); |
8020ceb5 | 482 | lttng_destroy_context(event->ctx); |
b5234c06 | 483 | free(event); |
8020ceb5 MD |
484 | } |
485 | ||
486 | /* | |
487 | * We have exclusive access to our metadata buffer (protected by the | |
17dfb34b | 488 | * ust_lock), so we can do racy operations such as looking for |
8020ceb5 MD |
489 | * remaining space left in packet and write, since mutual exclusion |
490 | * protects us from concurrent writes. | |
491 | */ | |
492 | int lttng_metadata_printf(struct ltt_session *session, | |
493 | const char *fmt, ...) | |
494 | { | |
495 | struct lib_ring_buffer_ctx ctx; | |
496 | struct ltt_channel *chan = session->metadata; | |
b5234c06 | 497 | char *str = NULL; |
8020ceb5 MD |
498 | int ret = 0, waitret; |
499 | size_t len, reserve_len, pos; | |
500 | va_list ap; | |
501 | ||
b5234c06 | 502 | WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active)); |
8020ceb5 MD |
503 | |
504 | va_start(ap, fmt); | |
b5234c06 | 505 | ret = vasprintf(&str, fmt, ap); |
8020ceb5 | 506 | va_end(ap); |
b5234c06 | 507 | if (ret < 0) |
8020ceb5 MD |
508 | return -ENOMEM; |
509 | ||
510 | len = strlen(str); | |
511 | pos = 0; | |
512 | ||
513 | for (pos = 0; pos < len; pos += reserve_len) { | |
514 | reserve_len = min_t(size_t, | |
1d498196 | 515 | chan->ops->packet_avail_size(chan->chan, chan->handle), |
8020ceb5 MD |
516 | len - pos); |
517 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, | |
1d498196 | 518 | sizeof(char), -1, chan->handle); |
8020ceb5 MD |
519 | /* |
520 | * We don't care about metadata buffer's records lost | |
521 | * count, because we always retry here. Report error if | |
522 | * we need to bail out after timeout or being | |
523 | * interrupted. | |
524 | */ | |
b5234c06 | 525 | waitret = wait_cond_interruptible_timeout( |
8020ceb5 MD |
526 | ({ |
527 | ret = chan->ops->event_reserve(&ctx, 0); | |
528 | ret != -ENOBUFS || !ret; | |
529 | }), | |
b5234c06 | 530 | LTTNG_METADATA_TIMEOUT_MSEC); |
b472cfc0 | 531 | if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) { |
b5234c06 MD |
532 | DBG("LTTng: Failure to write metadata to buffers (%s)\n", |
533 | waitret == -EINTR ? "interrupted" : | |
8020ceb5 | 534 | (ret == -ENOBUFS ? "timeout" : "I/O error")); |
b5234c06 | 535 | if (waitret == -EINTR) |
8020ceb5 MD |
536 | ret = waitret; |
537 | goto end; | |
538 | } | |
539 | chan->ops->event_write(&ctx, &str[pos], reserve_len); | |
540 | chan->ops->event_commit(&ctx); | |
541 | } | |
542 | end: | |
b5234c06 | 543 | free(str); |
8020ceb5 MD |
544 | return ret; |
545 | } | |
546 | ||
547 | static | |
548 | int _ltt_field_statedump(struct ltt_session *session, | |
549 | const struct lttng_event_field *field) | |
550 | { | |
551 | int ret = 0; | |
552 | ||
553 | switch (field->type.atype) { | |
554 | case atype_integer: | |
555 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 556 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8020ceb5 MD |
557 | field->type.u.basic.integer.size, |
558 | field->type.u.basic.integer.alignment, | |
559 | field->type.u.basic.integer.signedness, | |
560 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
561 | ? "none" | |
562 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
563 | ? "UTF8" | |
564 | : "ASCII", | |
565 | field->type.u.basic.integer.base, | |
8a98a75d | 566 | #if (BYTE_ORDER == BIG_ENDIAN) |
403c40b4 MD |
567 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
568 | #else | |
569 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
570 | #endif | |
571 | field->name); | |
572 | break; | |
573 | case atype_float: | |
574 | ret = lttng_metadata_printf(session, | |
8a98a75d | 575 | " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n", |
403c40b4 MD |
576 | field->type.u.basic._float.exp_dig, |
577 | field->type.u.basic._float.mant_dig, | |
578 | field->type.u.basic._float.alignment, | |
8a98a75d | 579 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
580 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
581 | #else | |
582 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
583 | #endif | |
584 | field->name); | |
585 | break; | |
586 | case atype_enum: | |
587 | ret = lttng_metadata_printf(session, | |
588 | " %s %s;\n", | |
589 | field->type.u.basic.enumeration.name, | |
590 | field->name); | |
591 | break; | |
592 | case atype_array: | |
593 | { | |
594 | const struct lttng_basic_type *elem_type; | |
595 | ||
596 | elem_type = &field->type.u.array.elem_type; | |
597 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 598 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8020ceb5 MD |
599 | elem_type->u.basic.integer.size, |
600 | elem_type->u.basic.integer.alignment, | |
601 | elem_type->u.basic.integer.signedness, | |
602 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
603 | ? "none" | |
604 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
605 | ? "UTF8" | |
606 | : "ASCII", | |
607 | elem_type->u.basic.integer.base, | |
8a98a75d | 608 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
609 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
610 | #else | |
611 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
612 | #endif | |
613 | field->name, field->type.u.array.length); | |
614 | break; | |
615 | } | |
616 | case atype_sequence: | |
617 | { | |
618 | const struct lttng_basic_type *elem_type; | |
619 | const struct lttng_basic_type *length_type; | |
620 | ||
621 | elem_type = &field->type.u.sequence.elem_type; | |
622 | length_type = &field->type.u.sequence.length_type; | |
623 | ret = lttng_metadata_printf(session, | |
624 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
625 | length_type->u.basic.integer.size, | |
626 | (unsigned int) length_type->u.basic.integer.alignment, | |
627 | length_type->u.basic.integer.signedness, | |
628 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
629 | ? "none" | |
630 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
631 | ? "UTF8" | |
632 | : "ASCII"), | |
633 | length_type->u.basic.integer.base, | |
8a98a75d | 634 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
635 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
636 | #else | |
637 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
638 | #endif | |
639 | field->name); | |
640 | if (ret) | |
641 | return ret; | |
642 | ||
643 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 644 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8020ceb5 MD |
645 | elem_type->u.basic.integer.size, |
646 | (unsigned int) elem_type->u.basic.integer.alignment, | |
647 | elem_type->u.basic.integer.signedness, | |
648 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
649 | ? "none" | |
650 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
651 | ? "UTF8" | |
652 | : "ASCII"), | |
653 | elem_type->u.basic.integer.base, | |
8a98a75d | 654 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
655 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
656 | #else | |
657 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
658 | #endif | |
659 | field->name, | |
660 | field->name); | |
661 | break; | |
662 | } | |
663 | ||
664 | case atype_string: | |
665 | /* Default encoding is UTF8 */ | |
666 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 667 | " string%s _%s;\n", |
8020ceb5 MD |
668 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
669 | " { encoding = ASCII; }" : "", | |
670 | field->name); | |
671 | break; | |
672 | default: | |
673 | WARN_ON_ONCE(1); | |
674 | return -EINVAL; | |
675 | } | |
676 | return ret; | |
677 | } | |
678 | ||
679 | static | |
680 | int _ltt_context_metadata_statedump(struct ltt_session *session, | |
681 | struct lttng_ctx *ctx) | |
682 | { | |
683 | int ret = 0; | |
684 | int i; | |
685 | ||
686 | if (!ctx) | |
687 | return 0; | |
688 | for (i = 0; i < ctx->nr_fields; i++) { | |
689 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
690 | ||
691 | ret = _ltt_field_statedump(session, &field->event_field); | |
692 | if (ret) | |
693 | return ret; | |
694 | } | |
695 | return ret; | |
696 | } | |
697 | ||
698 | static | |
699 | int _ltt_fields_metadata_statedump(struct ltt_session *session, | |
700 | struct ltt_event *event) | |
701 | { | |
702 | const struct lttng_event_desc *desc = event->desc; | |
703 | int ret = 0; | |
704 | int i; | |
705 | ||
706 | for (i = 0; i < desc->nr_fields; i++) { | |
707 | const struct lttng_event_field *field = &desc->fields[i]; | |
708 | ||
709 | ret = _ltt_field_statedump(session, field); | |
710 | if (ret) | |
711 | return ret; | |
712 | } | |
713 | return ret; | |
714 | } | |
715 | ||
716 | static | |
717 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
718 | struct ltt_channel *chan, | |
719 | struct ltt_event *event) | |
720 | { | |
721 | int ret = 0; | |
722 | ||
b5234c06 | 723 | if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
724 | return 0; |
725 | if (chan == session->metadata) | |
726 | return 0; | |
8165c8da MD |
727 | /* |
728 | * Don't print events for which probe load is pending. | |
729 | */ | |
730 | if (!event->desc) | |
731 | return 0; | |
8020ceb5 MD |
732 | |
733 | ret = lttng_metadata_printf(session, | |
734 | "event {\n" | |
735 | " name = %s;\n" | |
736 | " id = %u;\n" | |
737 | " stream_id = %u;\n", | |
738 | event->desc->name, | |
739 | event->id, | |
740 | event->chan->id); | |
741 | if (ret) | |
742 | goto end; | |
743 | ||
744 | if (event->ctx) { | |
745 | ret = lttng_metadata_printf(session, | |
746 | " context := struct {\n"); | |
747 | if (ret) | |
748 | goto end; | |
749 | } | |
750 | ret = _ltt_context_metadata_statedump(session, event->ctx); | |
751 | if (ret) | |
752 | goto end; | |
753 | if (event->ctx) { | |
754 | ret = lttng_metadata_printf(session, | |
755 | " };\n"); | |
756 | if (ret) | |
757 | goto end; | |
758 | } | |
759 | ||
760 | ret = lttng_metadata_printf(session, | |
761 | " fields := struct {\n" | |
762 | ); | |
763 | if (ret) | |
764 | goto end; | |
765 | ||
766 | ret = _ltt_fields_metadata_statedump(session, event); | |
767 | if (ret) | |
768 | goto end; | |
769 | ||
770 | /* | |
771 | * LTTng space reservation can only reserve multiples of the | |
772 | * byte size. | |
773 | */ | |
774 | ret = lttng_metadata_printf(session, | |
775 | " };\n" | |
776 | "};\n\n"); | |
777 | if (ret) | |
778 | goto end; | |
779 | ||
780 | event->metadata_dumped = 1; | |
781 | end: | |
782 | return ret; | |
783 | ||
784 | } | |
785 | ||
786 | static | |
787 | int _ltt_channel_metadata_statedump(struct ltt_session *session, | |
788 | struct ltt_channel *chan) | |
789 | { | |
790 | int ret = 0; | |
791 | ||
b5234c06 | 792 | if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
793 | return 0; |
794 | if (chan == session->metadata) | |
795 | return 0; | |
796 | ||
797 | WARN_ON_ONCE(!chan->header_type); | |
798 | ret = lttng_metadata_printf(session, | |
799 | "stream {\n" | |
800 | " id = %u;\n" | |
801 | " event.header := %s;\n" | |
802 | " packet.context := struct packet_context;\n", | |
803 | chan->id, | |
804 | chan->header_type == 1 ? "struct event_header_compact" : | |
805 | "struct event_header_large"); | |
806 | if (ret) | |
807 | goto end; | |
808 | ||
809 | if (chan->ctx) { | |
810 | ret = lttng_metadata_printf(session, | |
811 | " event.context := struct {\n"); | |
812 | if (ret) | |
813 | goto end; | |
814 | } | |
815 | ret = _ltt_context_metadata_statedump(session, chan->ctx); | |
816 | if (ret) | |
817 | goto end; | |
818 | if (chan->ctx) { | |
819 | ret = lttng_metadata_printf(session, | |
820 | " };\n"); | |
821 | if (ret) | |
822 | goto end; | |
823 | } | |
824 | ||
825 | ret = lttng_metadata_printf(session, | |
826 | "};\n\n"); | |
827 | ||
828 | chan->metadata_dumped = 1; | |
829 | end: | |
830 | return ret; | |
831 | } | |
832 | ||
833 | static | |
834 | int _ltt_stream_packet_context_declare(struct ltt_session *session) | |
835 | { | |
836 | return lttng_metadata_printf(session, | |
837 | "struct packet_context {\n" | |
838 | " uint64_t timestamp_begin;\n" | |
839 | " uint64_t timestamp_end;\n" | |
840 | " uint32_t events_discarded;\n" | |
841 | " uint32_t content_size;\n" | |
842 | " uint32_t packet_size;\n" | |
843 | " uint32_t cpu_id;\n" | |
844 | "};\n\n" | |
845 | ); | |
846 | } | |
847 | ||
848 | /* | |
849 | * Compact header: | |
850 | * id: range: 0 - 30. | |
851 | * id 31 is reserved to indicate an extended header. | |
852 | * | |
853 | * Large header: | |
854 | * id: range: 0 - 65534. | |
855 | * id 65535 is reserved to indicate an extended header. | |
856 | */ | |
857 | static | |
858 | int _ltt_event_header_declare(struct ltt_session *session) | |
859 | { | |
860 | return lttng_metadata_printf(session, | |
861 | "struct event_header_compact {\n" | |
862 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
863 | " variant <id> {\n" | |
864 | " struct {\n" | |
865 | " uint27_t timestamp;\n" | |
866 | " } compact;\n" | |
867 | " struct {\n" | |
868 | " uint32_t id;\n" | |
869 | " uint64_t timestamp;\n" | |
870 | " } extended;\n" | |
871 | " } v;\n" | |
872 | "} align(%u);\n" | |
873 | "\n" | |
874 | "struct event_header_large {\n" | |
875 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
876 | " variant <id> {\n" | |
877 | " struct {\n" | |
878 | " uint32_t timestamp;\n" | |
879 | " } compact;\n" | |
880 | " struct {\n" | |
881 | " uint32_t id;\n" | |
882 | " uint64_t timestamp;\n" | |
883 | " } extended;\n" | |
884 | " } v;\n" | |
885 | "} align(%u);\n\n", | |
1dbfff0c MD |
886 | lttng_alignof(uint32_t) * CHAR_BIT, |
887 | lttng_alignof(uint16_t) * CHAR_BIT | |
8020ceb5 MD |
888 | ); |
889 | } | |
890 | ||
891 | /* | |
892 | * Output metadata into this session's metadata buffers. | |
893 | */ | |
894 | static | |
895 | int _ltt_session_metadata_statedump(struct ltt_session *session) | |
896 | { | |
b5234c06 MD |
897 | unsigned char *uuid_c = session->uuid; |
898 | char uuid_s[37]; | |
8020ceb5 MD |
899 | struct ltt_channel *chan; |
900 | struct ltt_event *event; | |
901 | int ret = 0; | |
902 | ||
b5234c06 | 903 | if (!CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
904 | return 0; |
905 | if (session->metadata_dumped) | |
906 | goto skip_session; | |
907 | if (!session->metadata) { | |
b5234c06 | 908 | DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
8020ceb5 MD |
909 | return -EPERM; |
910 | } | |
911 | ||
912 | snprintf(uuid_s, sizeof(uuid_s), | |
913 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", | |
914 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
915 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
916 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
917 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
918 | ||
919 | ret = lttng_metadata_printf(session, | |
920 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" | |
921 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
922 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
923 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
924 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" | |
925 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
926 | "\n" | |
927 | "trace {\n" | |
928 | " major = %u;\n" | |
929 | " minor = %u;\n" | |
930 | " uuid = \"%s\";\n" | |
931 | " byte_order = %s;\n" | |
932 | " packet.header := struct {\n" | |
933 | " uint32_t magic;\n" | |
934 | " uint8_t uuid[16];\n" | |
935 | " uint32_t stream_id;\n" | |
936 | " };\n" | |
937 | "};\n\n", | |
1dbfff0c MD |
938 | lttng_alignof(uint8_t) * CHAR_BIT, |
939 | lttng_alignof(uint16_t) * CHAR_BIT, | |
940 | lttng_alignof(uint32_t) * CHAR_BIT, | |
941 | lttng_alignof(uint64_t) * CHAR_BIT, | |
8020ceb5 MD |
942 | CTF_VERSION_MAJOR, |
943 | CTF_VERSION_MINOR, | |
944 | uuid_s, | |
8a98a75d | 945 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
946 | "be" |
947 | #else | |
948 | "le" | |
949 | #endif | |
950 | ); | |
951 | if (ret) | |
952 | goto end; | |
953 | ||
954 | ret = _ltt_stream_packet_context_declare(session); | |
955 | if (ret) | |
956 | goto end; | |
957 | ||
958 | ret = _ltt_event_header_declare(session); | |
959 | if (ret) | |
960 | goto end; | |
961 | ||
962 | skip_session: | |
b5234c06 | 963 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
964 | ret = _ltt_channel_metadata_statedump(session, chan); |
965 | if (ret) | |
966 | goto end; | |
967 | } | |
968 | ||
b5234c06 | 969 | cds_list_for_each_entry(event, &session->events, list) { |
8020ceb5 MD |
970 | ret = _ltt_event_metadata_statedump(session, event->chan, event); |
971 | if (ret) | |
972 | goto end; | |
973 | } | |
974 | session->metadata_dumped = 1; | |
975 | end: | |
976 | return ret; | |
977 | } | |
978 | ||
979 | /** | |
980 | * ltt_transport_register - LTT transport registration | |
981 | * @transport: transport structure | |
982 | * | |
983 | * Registers a transport which can be used as output to extract the data out of | |
17dfb34b | 984 | * LTTng. Called with ust_lock held. |
8020ceb5 MD |
985 | */ |
986 | void ltt_transport_register(struct ltt_transport *transport) | |
987 | { | |
b5234c06 | 988 | cds_list_add_tail(&transport->node, <t_transport_list); |
8020ceb5 | 989 | } |
8020ceb5 MD |
990 | |
991 | /** | |
992 | * ltt_transport_unregister - LTT transport unregistration | |
993 | * @transport: transport structure | |
17dfb34b | 994 | * Called with ust_lock held. |
8020ceb5 MD |
995 | */ |
996 | void ltt_transport_unregister(struct ltt_transport *transport) | |
997 | { | |
b5234c06 | 998 | cds_list_del(&transport->node); |
8020ceb5 MD |
999 | } |
1000 | ||
1ea11eab | 1001 | void ltt_events_exit(void) |
8020ceb5 MD |
1002 | { |
1003 | struct ltt_session *session, *tmpsession; | |
1004 | ||
b5234c06 | 1005 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, list) |
8020ceb5 | 1006 | ltt_session_destroy(session); |
8020ceb5 | 1007 | } |