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 | |
37 | * control and probe registration. | |
38 | */ | |
39 | static DEFINE_MUTEX(sessions_mutex); | |
40 | ||
41 | void lock_ust(void) | |
42 | { | |
43 | pthread_mutex_lock(&sessions_mutex); | |
44 | } | |
45 | ||
46 | void unlock_ust(void) | |
47 | { | |
48 | pthread_mutex_unlock(&sessions_mutex); | |
49 | } | |
50 | ||
b5234c06 MD |
51 | static CDS_LIST_HEAD(sessions); |
52 | static CDS_LIST_HEAD(ltt_transport_list); | |
8165c8da MD |
53 | |
54 | /* | |
55 | * Pending probes hash table, containing the registered ltt events for | |
56 | * which tracepoint probes are still missing. Protected by the sessions | |
57 | * mutex. | |
58 | */ | |
59 | #define PENDING_PROBE_HASH_BITS 6 | |
60 | #define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS) | |
61 | static struct cds_hlist_head pending_probe_table[PENDING_PROBE_HASH_SIZE]; | |
62 | ||
63 | struct ust_pending_probe { | |
64 | struct ltt_event *event; | |
65 | struct cds_hlist_node node; | |
66 | char name[]; | |
67 | }; | |
8020ceb5 MD |
68 | |
69 | static void _ltt_event_destroy(struct ltt_event *event); | |
70 | static void _ltt_channel_destroy(struct ltt_channel *chan); | |
71 | static int _ltt_event_unregister(struct ltt_event *event); | |
72 | static | |
73 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
74 | struct ltt_channel *chan, | |
75 | struct ltt_event *event); | |
76 | static | |
77 | int _ltt_session_metadata_statedump(struct ltt_session *session); | |
78 | ||
8165c8da MD |
79 | /* |
80 | * called at event creation if probe is missing. | |
81 | * called with session mutex held. | |
82 | */ | |
83 | static | |
84 | int add_pending_probe(struct ltt_event *event, const char *name) | |
85 | { | |
86 | struct cds_hlist_head *head; | |
8165c8da MD |
87 | struct ust_pending_probe *e; |
88 | size_t name_len = strlen(name) + 1; | |
89 | u32 hash = jhash(name, name_len - 1, 0); | |
90 | ||
91 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; | |
92 | e = zmalloc(sizeof(struct ust_pending_probe) + name_len); | |
93 | if (!e) | |
94 | return -ENOMEM; | |
95 | memcpy(&e->name[0], name, name_len); | |
96 | cds_hlist_add_head(&e->node, head); | |
97 | e->event = event; | |
98 | event->pending_probe = e; | |
99 | return 0; | |
100 | } | |
101 | ||
102 | /* | |
103 | * remove a pending probe. called when at event teardown and when an | |
104 | * event is fixed (probe is loaded). | |
105 | * called with session mutex held. | |
106 | */ | |
107 | static | |
108 | void remove_pending_probe(struct ust_pending_probe *e) | |
109 | { | |
110 | if (!e) | |
111 | return; | |
112 | cds_hlist_del(&e->node); | |
113 | free(e); | |
114 | } | |
115 | ||
116 | /* | |
117 | * Called at library load: connect the probe on the events pending on | |
118 | * probe load. | |
119 | * called with session mutex held. | |
120 | */ | |
121 | int pending_probe_fix_events(const struct lttng_event_desc *desc) | |
122 | { | |
123 | struct cds_hlist_head *head; | |
124 | struct cds_hlist_node *node, *p; | |
125 | struct ust_pending_probe *e; | |
126 | const char *name = desc->name; | |
127 | size_t name_len = strlen(name) + 1; | |
128 | u32 hash = jhash(name, name_len - 1, 0); | |
129 | int ret = 0; | |
130 | ||
131 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; | |
132 | cds_hlist_for_each_entry_safe(e, node, p, head, node) { | |
133 | struct ltt_event *event; | |
134 | struct ltt_channel *chan; | |
135 | ||
136 | if (strcmp(name, e->name)) | |
137 | continue; | |
138 | event = e->event; | |
139 | chan = event->chan; | |
140 | assert(!event->desc); | |
141 | event->desc = desc; | |
142 | event->pending_probe = NULL; | |
143 | remove_pending_probe(e); | |
144 | ret |= __tracepoint_probe_register(name, | |
145 | event->desc->probe_callback, | |
146 | event); | |
147 | ret |= _ltt_event_metadata_statedump(chan->session, chan, | |
148 | event); | |
149 | } | |
150 | return ret; | |
151 | } | |
152 | ||
8020ceb5 MD |
153 | void synchronize_trace(void) |
154 | { | |
8020ceb5 | 155 | synchronize_rcu(); |
8020ceb5 MD |
156 | } |
157 | ||
158 | struct ltt_session *ltt_session_create(void) | |
159 | { | |
160 | struct ltt_session *session; | |
161 | ||
b5234c06 | 162 | session = zmalloc(sizeof(struct ltt_session)); |
8020ceb5 MD |
163 | if (!session) |
164 | return NULL; | |
1ea11eab | 165 | pthread_mutex_lock(&sessions_mutex); |
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); | |
170 | pthread_mutex_unlock(&sessions_mutex); | |
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 | pthread_mutex_lock(&sessions_mutex); |
181 | CMM_ACCESS_ONCE(session->active) = 0; | |
182 | cds_list_for_each_entry(event, &session->events, list) { | |
8020ceb5 MD |
183 | ret = _ltt_event_unregister(event); |
184 | WARN_ON(ret); | |
185 | } | |
186 | synchronize_trace(); /* Wait for in-flight events to complete */ | |
b5234c06 | 187 | cds_list_for_each_entry_safe(event, tmpevent, &session->events, list) |
8020ceb5 | 188 | _ltt_event_destroy(event); |
b5234c06 | 189 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list) |
8020ceb5 | 190 | _ltt_channel_destroy(chan); |
b5234c06 MD |
191 | cds_list_del(&session->list); |
192 | pthread_mutex_unlock(&sessions_mutex); | |
193 | free(session); | |
8020ceb5 MD |
194 | } |
195 | ||
976fe9ea | 196 | int ltt_session_enable(struct ltt_session *session) |
8020ceb5 MD |
197 | { |
198 | int ret = 0; | |
199 | struct ltt_channel *chan; | |
200 | ||
b5234c06 | 201 | pthread_mutex_lock(&sessions_mutex); |
8020ceb5 MD |
202 | if (session->active) { |
203 | ret = -EBUSY; | |
204 | goto end; | |
205 | } | |
206 | ||
207 | /* | |
208 | * Snapshot the number of events per channel to know the type of header | |
209 | * we need to use. | |
210 | */ | |
b5234c06 | 211 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
212 | if (chan->header_type) |
213 | continue; /* don't change it if session stop/restart */ | |
214 | if (chan->free_event_id < 31) | |
215 | chan->header_type = 1; /* compact */ | |
216 | else | |
217 | chan->header_type = 2; /* large */ | |
218 | } | |
219 | ||
b5234c06 MD |
220 | CMM_ACCESS_ONCE(session->active) = 1; |
221 | CMM_ACCESS_ONCE(session->been_active) = 1; | |
8020ceb5 | 222 | ret = _ltt_session_metadata_statedump(session); |
4b4de73e | 223 | if (ret) |
b5234c06 | 224 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 225 | end: |
b5234c06 | 226 | pthread_mutex_unlock(&sessions_mutex); |
8020ceb5 MD |
227 | return ret; |
228 | } | |
229 | ||
976fe9ea | 230 | int ltt_session_disable(struct ltt_session *session) |
8020ceb5 MD |
231 | { |
232 | int ret = 0; | |
233 | ||
b5234c06 | 234 | pthread_mutex_lock(&sessions_mutex); |
8020ceb5 MD |
235 | if (!session->active) { |
236 | ret = -EBUSY; | |
237 | goto end; | |
238 | } | |
b5234c06 | 239 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 240 | end: |
b5234c06 | 241 | pthread_mutex_unlock(&sessions_mutex); |
8020ceb5 MD |
242 | return ret; |
243 | } | |
244 | ||
976fe9ea MD |
245 | int ltt_channel_enable(struct ltt_channel *channel) |
246 | { | |
247 | int old; | |
248 | ||
9beb36ba MD |
249 | if (channel == channel->session->metadata) |
250 | return -EPERM; | |
b5234c06 | 251 | old = uatomic_xchg(&channel->enabled, 1); |
976fe9ea MD |
252 | if (old) |
253 | return -EEXIST; | |
254 | return 0; | |
255 | } | |
256 | ||
257 | int ltt_channel_disable(struct ltt_channel *channel) | |
258 | { | |
259 | int old; | |
260 | ||
9beb36ba MD |
261 | if (channel == channel->session->metadata) |
262 | return -EPERM; | |
b5234c06 | 263 | old = uatomic_xchg(&channel->enabled, 0); |
976fe9ea MD |
264 | if (!old) |
265 | return -EEXIST; | |
266 | return 0; | |
267 | } | |
268 | ||
269 | int ltt_event_enable(struct ltt_event *event) | |
270 | { | |
271 | int old; | |
272 | ||
9beb36ba MD |
273 | if (event->chan == event->chan->session->metadata) |
274 | return -EPERM; | |
b5234c06 | 275 | old = uatomic_xchg(&event->enabled, 1); |
976fe9ea MD |
276 | if (old) |
277 | return -EEXIST; | |
278 | return 0; | |
279 | } | |
280 | ||
281 | int ltt_event_disable(struct ltt_event *event) | |
282 | { | |
283 | int old; | |
284 | ||
9beb36ba MD |
285 | if (event->chan == event->chan->session->metadata) |
286 | return -EPERM; | |
b5234c06 | 287 | old = uatomic_xchg(&event->enabled, 0); |
976fe9ea MD |
288 | if (!old) |
289 | return -EEXIST; | |
290 | return 0; | |
291 | } | |
292 | ||
8020ceb5 MD |
293 | static struct ltt_transport *ltt_transport_find(const char *name) |
294 | { | |
295 | struct ltt_transport *transport; | |
296 | ||
b5234c06 | 297 | cds_list_for_each_entry(transport, <t_transport_list, node) { |
8020ceb5 MD |
298 | if (!strcmp(transport->name, name)) |
299 | return transport; | |
300 | } | |
301 | return NULL; | |
302 | } | |
303 | ||
304 | struct ltt_channel *ltt_channel_create(struct ltt_session *session, | |
305 | const char *transport_name, | |
306 | void *buf_addr, | |
307 | size_t subbuf_size, size_t num_subbuf, | |
308 | unsigned int switch_timer_interval, | |
f4681817 | 309 | unsigned int read_timer_interval) |
8020ceb5 MD |
310 | { |
311 | struct ltt_channel *chan; | |
312 | struct ltt_transport *transport; | |
313 | ||
b5234c06 | 314 | pthread_mutex_lock(&sessions_mutex); |
8020ceb5 MD |
315 | if (session->been_active) |
316 | goto active; /* Refuse to add channel to active session */ | |
317 | transport = ltt_transport_find(transport_name); | |
318 | if (!transport) { | |
b5234c06 | 319 | DBG("LTTng transport %s not found\n", |
8020ceb5 MD |
320 | transport_name); |
321 | goto notransport; | |
322 | } | |
b5234c06 | 323 | chan = zmalloc(sizeof(struct ltt_channel)); |
8020ceb5 MD |
324 | if (!chan) |
325 | goto nomem; | |
326 | chan->session = session; | |
327 | chan->id = session->free_chan_id++; | |
328 | /* | |
329 | * Note: the channel creation op already writes into the packet | |
330 | * headers. Therefore the "chan" information used as input | |
331 | * should be already accessible. | |
332 | */ | |
1d498196 | 333 | transport->ops.channel_create("[lttng]", chan, buf_addr, |
8020ceb5 | 334 | subbuf_size, num_subbuf, switch_timer_interval, |
8d8a24c8 | 335 | read_timer_interval); |
8020ceb5 MD |
336 | if (!chan->chan) |
337 | goto create_error; | |
976fe9ea | 338 | chan->enabled = 1; |
8020ceb5 | 339 | chan->ops = &transport->ops; |
b5234c06 MD |
340 | cds_list_add(&chan->list, &session->chan); |
341 | pthread_mutex_unlock(&sessions_mutex); | |
8020ceb5 MD |
342 | return chan; |
343 | ||
344 | create_error: | |
b5234c06 | 345 | free(chan); |
8020ceb5 MD |
346 | nomem: |
347 | notransport: | |
348 | active: | |
b5234c06 | 349 | pthread_mutex_unlock(&sessions_mutex); |
8020ceb5 MD |
350 | return NULL; |
351 | } | |
352 | ||
353 | /* | |
354 | * Only used internally at session destruction. | |
355 | */ | |
356 | static | |
357 | void _ltt_channel_destroy(struct ltt_channel *chan) | |
358 | { | |
1d498196 | 359 | chan->ops->channel_destroy(chan); |
b5234c06 | 360 | cds_list_del(&chan->list); |
8020ceb5 | 361 | lttng_destroy_context(chan->ctx); |
b5234c06 | 362 | free(chan); |
8020ceb5 MD |
363 | } |
364 | ||
365 | /* | |
366 | * Supports event creation while tracing session is active. | |
367 | */ | |
368 | struct ltt_event *ltt_event_create(struct ltt_channel *chan, | |
b5234c06 | 369 | struct lttng_ust_event *event_param, |
8020ceb5 MD |
370 | void *filter) |
371 | { | |
372 | struct ltt_event *event; | |
373 | int ret; | |
374 | ||
b5234c06 | 375 | pthread_mutex_lock(&sessions_mutex); |
8165c8da | 376 | if (chan->used_event_id == -1UL) |
8020ceb5 MD |
377 | goto full; |
378 | /* | |
379 | * This is O(n^2) (for each event, the loop is called at event | |
380 | * creation). Might require a hash if we have lots of events. | |
381 | */ | |
b5234c06 | 382 | cds_list_for_each_entry(event, &chan->session->events, list) |
8165c8da | 383 | if (event->desc && !strcmp(event->desc->name, event_param->name)) |
8020ceb5 | 384 | goto exist; |
b5234c06 | 385 | event = zmalloc(sizeof(struct ltt_event)); |
8020ceb5 MD |
386 | if (!event) |
387 | goto cache_error; | |
388 | event->chan = chan; | |
389 | event->filter = filter; | |
8165c8da MD |
390 | /* |
391 | * used_event_id counts the maximum number of event IDs that can | |
392 | * register if all probes register. | |
393 | */ | |
394 | chan->used_event_id++; | |
976fe9ea | 395 | event->enabled = 1; |
8020ceb5 MD |
396 | event->instrumentation = event_param->instrumentation; |
397 | /* Populate ltt_event structure before tracepoint registration. */ | |
b5234c06 | 398 | cmm_smp_wmb(); |
8020ceb5 | 399 | switch (event_param->instrumentation) { |
b5234c06 | 400 | case LTTNG_UST_TRACEPOINT: |
8020ceb5 | 401 | event->desc = ltt_event_get(event_param->name); |
8165c8da MD |
402 | if (event->desc) { |
403 | ret = __tracepoint_probe_register(event_param->name, | |
404 | event->desc->probe_callback, | |
405 | event); | |
406 | if (ret) | |
407 | goto register_error; | |
408 | event->id = chan->free_event_id++; | |
409 | } else { | |
410 | /* | |
411 | * If the probe is not present, event->desc stays NULL, | |
412 | * waiting for the probe to register, and the event->id | |
413 | * stays unallocated. | |
414 | */ | |
415 | ret = add_pending_probe(event, event_param->name); | |
416 | if (ret) | |
417 | goto add_pending_error; | |
418 | } | |
8020ceb5 | 419 | break; |
8020ceb5 MD |
420 | default: |
421 | WARN_ON_ONCE(1); | |
422 | } | |
8165c8da MD |
423 | if (event->desc) { |
424 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); | |
425 | if (ret) | |
426 | goto statedump_error; | |
427 | } | |
b5234c06 MD |
428 | cds_list_add(&event->list, &chan->session->events); |
429 | pthread_mutex_unlock(&sessions_mutex); | |
8020ceb5 MD |
430 | return event; |
431 | ||
432 | statedump_error: | |
8165c8da MD |
433 | if (event->desc) { |
434 | WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name, | |
435 | event->desc->probe_callback, | |
436 | event)); | |
437 | ltt_event_put(event->desc); | |
438 | } | |
439 | add_pending_error: | |
8020ceb5 | 440 | register_error: |
b5234c06 | 441 | free(event); |
8020ceb5 MD |
442 | cache_error: |
443 | exist: | |
444 | full: | |
b5234c06 | 445 | pthread_mutex_unlock(&sessions_mutex); |
8020ceb5 MD |
446 | return NULL; |
447 | } | |
448 | ||
449 | /* | |
450 | * Only used internally at session destruction. | |
451 | */ | |
452 | int _ltt_event_unregister(struct ltt_event *event) | |
453 | { | |
454 | int ret = -EINVAL; | |
455 | ||
456 | switch (event->instrumentation) { | |
b5234c06 | 457 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
458 | if (event->desc) { |
459 | ret = __tracepoint_probe_unregister(event->desc->name, | |
460 | event->desc->probe_callback, | |
461 | event); | |
462 | if (ret) | |
463 | return ret; | |
464 | } else { | |
465 | remove_pending_probe(event->pending_probe); | |
466 | ret = 0; | |
467 | } | |
8020ceb5 | 468 | break; |
8020ceb5 MD |
469 | default: |
470 | WARN_ON_ONCE(1); | |
471 | } | |
472 | return ret; | |
473 | } | |
474 | ||
475 | /* | |
476 | * Only used internally at session destruction. | |
477 | */ | |
478 | static | |
479 | void _ltt_event_destroy(struct ltt_event *event) | |
480 | { | |
481 | switch (event->instrumentation) { | |
b5234c06 | 482 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
483 | if (event->desc) { |
484 | ltt_event_put(event->desc); | |
485 | } | |
8020ceb5 | 486 | break; |
8020ceb5 MD |
487 | default: |
488 | WARN_ON_ONCE(1); | |
489 | } | |
b5234c06 | 490 | cds_list_del(&event->list); |
8020ceb5 | 491 | lttng_destroy_context(event->ctx); |
b5234c06 | 492 | free(event); |
8020ceb5 MD |
493 | } |
494 | ||
495 | /* | |
496 | * We have exclusive access to our metadata buffer (protected by the | |
497 | * sessions_mutex), so we can do racy operations such as looking for | |
498 | * remaining space left in packet and write, since mutual exclusion | |
499 | * protects us from concurrent writes. | |
500 | */ | |
501 | int lttng_metadata_printf(struct ltt_session *session, | |
502 | const char *fmt, ...) | |
503 | { | |
504 | struct lib_ring_buffer_ctx ctx; | |
505 | struct ltt_channel *chan = session->metadata; | |
b5234c06 | 506 | char *str = NULL; |
8020ceb5 MD |
507 | int ret = 0, waitret; |
508 | size_t len, reserve_len, pos; | |
509 | va_list ap; | |
510 | ||
b5234c06 | 511 | WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active)); |
8020ceb5 MD |
512 | |
513 | va_start(ap, fmt); | |
b5234c06 | 514 | ret = vasprintf(&str, fmt, ap); |
8020ceb5 | 515 | va_end(ap); |
b5234c06 | 516 | if (ret < 0) |
8020ceb5 MD |
517 | return -ENOMEM; |
518 | ||
519 | len = strlen(str); | |
520 | pos = 0; | |
521 | ||
522 | for (pos = 0; pos < len; pos += reserve_len) { | |
523 | reserve_len = min_t(size_t, | |
1d498196 | 524 | chan->ops->packet_avail_size(chan->chan, chan->handle), |
8020ceb5 MD |
525 | len - pos); |
526 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, | |
1d498196 | 527 | sizeof(char), -1, chan->handle); |
8020ceb5 MD |
528 | /* |
529 | * We don't care about metadata buffer's records lost | |
530 | * count, because we always retry here. Report error if | |
531 | * we need to bail out after timeout or being | |
532 | * interrupted. | |
533 | */ | |
b5234c06 | 534 | waitret = wait_cond_interruptible_timeout( |
8020ceb5 MD |
535 | ({ |
536 | ret = chan->ops->event_reserve(&ctx, 0); | |
537 | ret != -ENOBUFS || !ret; | |
538 | }), | |
b5234c06 | 539 | LTTNG_METADATA_TIMEOUT_MSEC); |
b472cfc0 | 540 | if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) { |
b5234c06 MD |
541 | DBG("LTTng: Failure to write metadata to buffers (%s)\n", |
542 | waitret == -EINTR ? "interrupted" : | |
8020ceb5 | 543 | (ret == -ENOBUFS ? "timeout" : "I/O error")); |
b5234c06 | 544 | if (waitret == -EINTR) |
8020ceb5 MD |
545 | ret = waitret; |
546 | goto end; | |
547 | } | |
548 | chan->ops->event_write(&ctx, &str[pos], reserve_len); | |
549 | chan->ops->event_commit(&ctx); | |
550 | } | |
551 | end: | |
b5234c06 | 552 | free(str); |
8020ceb5 MD |
553 | return ret; |
554 | } | |
555 | ||
556 | static | |
557 | int _ltt_field_statedump(struct ltt_session *session, | |
558 | const struct lttng_event_field *field) | |
559 | { | |
560 | int ret = 0; | |
561 | ||
562 | switch (field->type.atype) { | |
563 | case atype_integer: | |
564 | ret = lttng_metadata_printf(session, | |
565 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s;\n", | |
566 | field->type.u.basic.integer.size, | |
567 | field->type.u.basic.integer.alignment, | |
568 | field->type.u.basic.integer.signedness, | |
569 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
570 | ? "none" | |
571 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
572 | ? "UTF8" | |
573 | : "ASCII", | |
574 | field->type.u.basic.integer.base, | |
403c40b4 MD |
575 | #ifdef __BIG_ENDIAN |
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_float: | |
583 | ret = lttng_metadata_printf(session, | |
584 | " floating_point { exp_dig = %u; mant_dig = %u; align = %u; } %s;\n", | |
585 | field->type.u.basic._float.exp_dig, | |
586 | field->type.u.basic._float.mant_dig, | |
587 | field->type.u.basic._float.alignment, | |
588 | #ifdef __BIG_ENDIAN | |
8020ceb5 MD |
589 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
590 | #else | |
591 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
592 | #endif | |
593 | field->name); | |
594 | break; | |
595 | case atype_enum: | |
596 | ret = lttng_metadata_printf(session, | |
597 | " %s %s;\n", | |
598 | field->type.u.basic.enumeration.name, | |
599 | field->name); | |
600 | break; | |
601 | case atype_array: | |
602 | { | |
603 | const struct lttng_basic_type *elem_type; | |
604 | ||
605 | elem_type = &field->type.u.array.elem_type; | |
606 | ret = lttng_metadata_printf(session, | |
607 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[%u];\n", | |
608 | elem_type->u.basic.integer.size, | |
609 | elem_type->u.basic.integer.alignment, | |
610 | elem_type->u.basic.integer.signedness, | |
611 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
612 | ? "none" | |
613 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
614 | ? "UTF8" | |
615 | : "ASCII", | |
616 | elem_type->u.basic.integer.base, | |
403c40b4 | 617 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
618 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
619 | #else | |
620 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
621 | #endif | |
622 | field->name, field->type.u.array.length); | |
623 | break; | |
624 | } | |
625 | case atype_sequence: | |
626 | { | |
627 | const struct lttng_basic_type *elem_type; | |
628 | const struct lttng_basic_type *length_type; | |
629 | ||
630 | elem_type = &field->type.u.sequence.elem_type; | |
631 | length_type = &field->type.u.sequence.length_type; | |
632 | ret = lttng_metadata_printf(session, | |
633 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
634 | length_type->u.basic.integer.size, | |
635 | (unsigned int) length_type->u.basic.integer.alignment, | |
636 | length_type->u.basic.integer.signedness, | |
637 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
638 | ? "none" | |
639 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
640 | ? "UTF8" | |
641 | : "ASCII"), | |
642 | length_type->u.basic.integer.base, | |
403c40b4 | 643 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
644 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
645 | #else | |
646 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
647 | #endif | |
648 | field->name); | |
649 | if (ret) | |
650 | return ret; | |
651 | ||
652 | ret = lttng_metadata_printf(session, | |
653 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } %s[ __%s_length ];\n", | |
654 | elem_type->u.basic.integer.size, | |
655 | (unsigned int) elem_type->u.basic.integer.alignment, | |
656 | elem_type->u.basic.integer.signedness, | |
657 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
658 | ? "none" | |
659 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
660 | ? "UTF8" | |
661 | : "ASCII"), | |
662 | elem_type->u.basic.integer.base, | |
403c40b4 | 663 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
664 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
665 | #else | |
666 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
667 | #endif | |
668 | field->name, | |
669 | field->name); | |
670 | break; | |
671 | } | |
672 | ||
673 | case atype_string: | |
674 | /* Default encoding is UTF8 */ | |
675 | ret = lttng_metadata_printf(session, | |
676 | " string%s %s;\n", | |
677 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? | |
678 | " { encoding = ASCII; }" : "", | |
679 | field->name); | |
680 | break; | |
681 | default: | |
682 | WARN_ON_ONCE(1); | |
683 | return -EINVAL; | |
684 | } | |
685 | return ret; | |
686 | } | |
687 | ||
688 | static | |
689 | int _ltt_context_metadata_statedump(struct ltt_session *session, | |
690 | struct lttng_ctx *ctx) | |
691 | { | |
692 | int ret = 0; | |
693 | int i; | |
694 | ||
695 | if (!ctx) | |
696 | return 0; | |
697 | for (i = 0; i < ctx->nr_fields; i++) { | |
698 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
699 | ||
700 | ret = _ltt_field_statedump(session, &field->event_field); | |
701 | if (ret) | |
702 | return ret; | |
703 | } | |
704 | return ret; | |
705 | } | |
706 | ||
707 | static | |
708 | int _ltt_fields_metadata_statedump(struct ltt_session *session, | |
709 | struct ltt_event *event) | |
710 | { | |
711 | const struct lttng_event_desc *desc = event->desc; | |
712 | int ret = 0; | |
713 | int i; | |
714 | ||
715 | for (i = 0; i < desc->nr_fields; i++) { | |
716 | const struct lttng_event_field *field = &desc->fields[i]; | |
717 | ||
718 | ret = _ltt_field_statedump(session, field); | |
719 | if (ret) | |
720 | return ret; | |
721 | } | |
722 | return ret; | |
723 | } | |
724 | ||
725 | static | |
726 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
727 | struct ltt_channel *chan, | |
728 | struct ltt_event *event) | |
729 | { | |
730 | int ret = 0; | |
731 | ||
b5234c06 | 732 | if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
733 | return 0; |
734 | if (chan == session->metadata) | |
735 | return 0; | |
8165c8da MD |
736 | /* |
737 | * Don't print events for which probe load is pending. | |
738 | */ | |
739 | if (!event->desc) | |
740 | return 0; | |
8020ceb5 MD |
741 | |
742 | ret = lttng_metadata_printf(session, | |
743 | "event {\n" | |
744 | " name = %s;\n" | |
745 | " id = %u;\n" | |
746 | " stream_id = %u;\n", | |
747 | event->desc->name, | |
748 | event->id, | |
749 | event->chan->id); | |
750 | if (ret) | |
751 | goto end; | |
752 | ||
753 | if (event->ctx) { | |
754 | ret = lttng_metadata_printf(session, | |
755 | " context := struct {\n"); | |
756 | if (ret) | |
757 | goto end; | |
758 | } | |
759 | ret = _ltt_context_metadata_statedump(session, event->ctx); | |
760 | if (ret) | |
761 | goto end; | |
762 | if (event->ctx) { | |
763 | ret = lttng_metadata_printf(session, | |
764 | " };\n"); | |
765 | if (ret) | |
766 | goto end; | |
767 | } | |
768 | ||
769 | ret = lttng_metadata_printf(session, | |
770 | " fields := struct {\n" | |
771 | ); | |
772 | if (ret) | |
773 | goto end; | |
774 | ||
775 | ret = _ltt_fields_metadata_statedump(session, event); | |
776 | if (ret) | |
777 | goto end; | |
778 | ||
779 | /* | |
780 | * LTTng space reservation can only reserve multiples of the | |
781 | * byte size. | |
782 | */ | |
783 | ret = lttng_metadata_printf(session, | |
784 | " };\n" | |
785 | "};\n\n"); | |
786 | if (ret) | |
787 | goto end; | |
788 | ||
789 | event->metadata_dumped = 1; | |
790 | end: | |
791 | return ret; | |
792 | ||
793 | } | |
794 | ||
795 | static | |
796 | int _ltt_channel_metadata_statedump(struct ltt_session *session, | |
797 | struct ltt_channel *chan) | |
798 | { | |
799 | int ret = 0; | |
800 | ||
b5234c06 | 801 | if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
802 | return 0; |
803 | if (chan == session->metadata) | |
804 | return 0; | |
805 | ||
806 | WARN_ON_ONCE(!chan->header_type); | |
807 | ret = lttng_metadata_printf(session, | |
808 | "stream {\n" | |
809 | " id = %u;\n" | |
810 | " event.header := %s;\n" | |
811 | " packet.context := struct packet_context;\n", | |
812 | chan->id, | |
813 | chan->header_type == 1 ? "struct event_header_compact" : | |
814 | "struct event_header_large"); | |
815 | if (ret) | |
816 | goto end; | |
817 | ||
818 | if (chan->ctx) { | |
819 | ret = lttng_metadata_printf(session, | |
820 | " event.context := struct {\n"); | |
821 | if (ret) | |
822 | goto end; | |
823 | } | |
824 | ret = _ltt_context_metadata_statedump(session, chan->ctx); | |
825 | if (ret) | |
826 | goto end; | |
827 | if (chan->ctx) { | |
828 | ret = lttng_metadata_printf(session, | |
829 | " };\n"); | |
830 | if (ret) | |
831 | goto end; | |
832 | } | |
833 | ||
834 | ret = lttng_metadata_printf(session, | |
835 | "};\n\n"); | |
836 | ||
837 | chan->metadata_dumped = 1; | |
838 | end: | |
839 | return ret; | |
840 | } | |
841 | ||
842 | static | |
843 | int _ltt_stream_packet_context_declare(struct ltt_session *session) | |
844 | { | |
845 | return lttng_metadata_printf(session, | |
846 | "struct packet_context {\n" | |
847 | " uint64_t timestamp_begin;\n" | |
848 | " uint64_t timestamp_end;\n" | |
849 | " uint32_t events_discarded;\n" | |
850 | " uint32_t content_size;\n" | |
851 | " uint32_t packet_size;\n" | |
852 | " uint32_t cpu_id;\n" | |
853 | "};\n\n" | |
854 | ); | |
855 | } | |
856 | ||
857 | /* | |
858 | * Compact header: | |
859 | * id: range: 0 - 30. | |
860 | * id 31 is reserved to indicate an extended header. | |
861 | * | |
862 | * Large header: | |
863 | * id: range: 0 - 65534. | |
864 | * id 65535 is reserved to indicate an extended header. | |
865 | */ | |
866 | static | |
867 | int _ltt_event_header_declare(struct ltt_session *session) | |
868 | { | |
869 | return lttng_metadata_printf(session, | |
870 | "struct event_header_compact {\n" | |
871 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
872 | " variant <id> {\n" | |
873 | " struct {\n" | |
874 | " uint27_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" | |
882 | "\n" | |
883 | "struct event_header_large {\n" | |
884 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
885 | " variant <id> {\n" | |
886 | " struct {\n" | |
887 | " uint32_t timestamp;\n" | |
888 | " } compact;\n" | |
889 | " struct {\n" | |
890 | " uint32_t id;\n" | |
891 | " uint64_t timestamp;\n" | |
892 | " } extended;\n" | |
893 | " } v;\n" | |
894 | "} align(%u);\n\n", | |
1dbfff0c MD |
895 | lttng_alignof(uint32_t) * CHAR_BIT, |
896 | lttng_alignof(uint16_t) * CHAR_BIT | |
8020ceb5 MD |
897 | ); |
898 | } | |
899 | ||
900 | /* | |
901 | * Output metadata into this session's metadata buffers. | |
902 | */ | |
903 | static | |
904 | int _ltt_session_metadata_statedump(struct ltt_session *session) | |
905 | { | |
b5234c06 MD |
906 | unsigned char *uuid_c = session->uuid; |
907 | char uuid_s[37]; | |
8020ceb5 MD |
908 | struct ltt_channel *chan; |
909 | struct ltt_event *event; | |
910 | int ret = 0; | |
911 | ||
b5234c06 | 912 | if (!CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
913 | return 0; |
914 | if (session->metadata_dumped) | |
915 | goto skip_session; | |
916 | if (!session->metadata) { | |
b5234c06 | 917 | DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
8020ceb5 MD |
918 | return -EPERM; |
919 | } | |
920 | ||
921 | snprintf(uuid_s, sizeof(uuid_s), | |
922 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", | |
923 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
924 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
925 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
926 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
927 | ||
928 | ret = lttng_metadata_printf(session, | |
929 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" | |
930 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
931 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
932 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
933 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" | |
934 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
935 | "\n" | |
936 | "trace {\n" | |
937 | " major = %u;\n" | |
938 | " minor = %u;\n" | |
939 | " uuid = \"%s\";\n" | |
940 | " byte_order = %s;\n" | |
941 | " packet.header := struct {\n" | |
942 | " uint32_t magic;\n" | |
943 | " uint8_t uuid[16];\n" | |
944 | " uint32_t stream_id;\n" | |
945 | " };\n" | |
946 | "};\n\n", | |
1dbfff0c MD |
947 | lttng_alignof(uint8_t) * CHAR_BIT, |
948 | lttng_alignof(uint16_t) * CHAR_BIT, | |
949 | lttng_alignof(uint32_t) * CHAR_BIT, | |
950 | lttng_alignof(uint64_t) * CHAR_BIT, | |
8020ceb5 MD |
951 | CTF_VERSION_MAJOR, |
952 | CTF_VERSION_MINOR, | |
953 | uuid_s, | |
403c40b4 | 954 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
955 | "be" |
956 | #else | |
957 | "le" | |
958 | #endif | |
959 | ); | |
960 | if (ret) | |
961 | goto end; | |
962 | ||
963 | ret = _ltt_stream_packet_context_declare(session); | |
964 | if (ret) | |
965 | goto end; | |
966 | ||
967 | ret = _ltt_event_header_declare(session); | |
968 | if (ret) | |
969 | goto end; | |
970 | ||
971 | skip_session: | |
b5234c06 | 972 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
973 | ret = _ltt_channel_metadata_statedump(session, chan); |
974 | if (ret) | |
975 | goto end; | |
976 | } | |
977 | ||
b5234c06 | 978 | cds_list_for_each_entry(event, &session->events, list) { |
8020ceb5 MD |
979 | ret = _ltt_event_metadata_statedump(session, event->chan, event); |
980 | if (ret) | |
981 | goto end; | |
982 | } | |
983 | session->metadata_dumped = 1; | |
984 | end: | |
985 | return ret; | |
986 | } | |
987 | ||
988 | /** | |
989 | * ltt_transport_register - LTT transport registration | |
990 | * @transport: transport structure | |
991 | * | |
992 | * Registers a transport which can be used as output to extract the data out of | |
b5234c06 | 993 | * LTTng. |
8020ceb5 MD |
994 | */ |
995 | void ltt_transport_register(struct ltt_transport *transport) | |
996 | { | |
b5234c06 MD |
997 | pthread_mutex_lock(&sessions_mutex); |
998 | cds_list_add_tail(&transport->node, <t_transport_list); | |
999 | pthread_mutex_unlock(&sessions_mutex); | |
8020ceb5 | 1000 | } |
8020ceb5 MD |
1001 | |
1002 | /** | |
1003 | * ltt_transport_unregister - LTT transport unregistration | |
1004 | * @transport: transport structure | |
1005 | */ | |
1006 | void ltt_transport_unregister(struct ltt_transport *transport) | |
1007 | { | |
b5234c06 MD |
1008 | pthread_mutex_lock(&sessions_mutex); |
1009 | cds_list_del(&transport->node); | |
1010 | pthread_mutex_unlock(&sessions_mutex); | |
8020ceb5 MD |
1011 | } |
1012 | ||
1ea11eab | 1013 | void ltt_events_exit(void) |
8020ceb5 MD |
1014 | { |
1015 | struct ltt_session *session, *tmpsession; | |
1016 | ||
b5234c06 | 1017 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, list) |
8020ceb5 | 1018 | ltt_session_destroy(session); |
8020ceb5 | 1019 | } |