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