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, | |
193183fb MD |
302 | unsigned int read_timer_interval, |
303 | int *shm_fd, int *wait_fd, | |
304 | uint64_t *memory_map_size) | |
8020ceb5 MD |
305 | { |
306 | struct ltt_channel *chan; | |
307 | struct ltt_transport *transport; | |
308 | ||
8020ceb5 MD |
309 | if (session->been_active) |
310 | goto active; /* Refuse to add channel to active session */ | |
311 | transport = ltt_transport_find(transport_name); | |
312 | if (!transport) { | |
b5234c06 | 313 | DBG("LTTng transport %s not found\n", |
8020ceb5 MD |
314 | transport_name); |
315 | goto notransport; | |
316 | } | |
b5234c06 | 317 | chan = zmalloc(sizeof(struct ltt_channel)); |
8020ceb5 MD |
318 | if (!chan) |
319 | goto nomem; | |
320 | chan->session = session; | |
321 | chan->id = session->free_chan_id++; | |
322 | /* | |
323 | * Note: the channel creation op already writes into the packet | |
324 | * headers. Therefore the "chan" information used as input | |
325 | * should be already accessible. | |
326 | */ | |
1d498196 | 327 | transport->ops.channel_create("[lttng]", chan, buf_addr, |
8020ceb5 | 328 | subbuf_size, num_subbuf, switch_timer_interval, |
193183fb MD |
329 | read_timer_interval, shm_fd, wait_fd, |
330 | memory_map_size); | |
8020ceb5 MD |
331 | if (!chan->chan) |
332 | goto create_error; | |
976fe9ea | 333 | chan->enabled = 1; |
8020ceb5 | 334 | chan->ops = &transport->ops; |
b5234c06 | 335 | cds_list_add(&chan->list, &session->chan); |
8020ceb5 MD |
336 | return chan; |
337 | ||
338 | create_error: | |
b5234c06 | 339 | free(chan); |
8020ceb5 MD |
340 | nomem: |
341 | notransport: | |
342 | active: | |
8020ceb5 MD |
343 | return NULL; |
344 | } | |
345 | ||
346 | /* | |
347 | * Only used internally at session destruction. | |
348 | */ | |
349 | static | |
350 | void _ltt_channel_destroy(struct ltt_channel *chan) | |
351 | { | |
1d498196 | 352 | chan->ops->channel_destroy(chan); |
b5234c06 | 353 | cds_list_del(&chan->list); |
8020ceb5 | 354 | lttng_destroy_context(chan->ctx); |
b5234c06 | 355 | free(chan); |
8020ceb5 MD |
356 | } |
357 | ||
358 | /* | |
359 | * Supports event creation while tracing session is active. | |
360 | */ | |
361 | struct ltt_event *ltt_event_create(struct ltt_channel *chan, | |
b5234c06 | 362 | struct lttng_ust_event *event_param, |
8020ceb5 MD |
363 | void *filter) |
364 | { | |
365 | struct ltt_event *event; | |
366 | int ret; | |
367 | ||
8165c8da | 368 | if (chan->used_event_id == -1UL) |
8020ceb5 MD |
369 | goto full; |
370 | /* | |
371 | * This is O(n^2) (for each event, the loop is called at event | |
372 | * creation). Might require a hash if we have lots of events. | |
373 | */ | |
b5234c06 | 374 | cds_list_for_each_entry(event, &chan->session->events, list) |
8165c8da | 375 | if (event->desc && !strcmp(event->desc->name, event_param->name)) |
8020ceb5 | 376 | goto exist; |
b5234c06 | 377 | event = zmalloc(sizeof(struct ltt_event)); |
8020ceb5 MD |
378 | if (!event) |
379 | goto cache_error; | |
380 | event->chan = chan; | |
381 | event->filter = filter; | |
8165c8da MD |
382 | /* |
383 | * used_event_id counts the maximum number of event IDs that can | |
384 | * register if all probes register. | |
385 | */ | |
386 | chan->used_event_id++; | |
976fe9ea | 387 | event->enabled = 1; |
8020ceb5 MD |
388 | event->instrumentation = event_param->instrumentation; |
389 | /* Populate ltt_event structure before tracepoint registration. */ | |
b5234c06 | 390 | cmm_smp_wmb(); |
8020ceb5 | 391 | switch (event_param->instrumentation) { |
b5234c06 | 392 | case LTTNG_UST_TRACEPOINT: |
8020ceb5 | 393 | event->desc = ltt_event_get(event_param->name); |
8165c8da MD |
394 | if (event->desc) { |
395 | ret = __tracepoint_probe_register(event_param->name, | |
396 | event->desc->probe_callback, | |
397 | event); | |
398 | if (ret) | |
399 | goto register_error; | |
400 | event->id = chan->free_event_id++; | |
401 | } else { | |
402 | /* | |
403 | * If the probe is not present, event->desc stays NULL, | |
404 | * waiting for the probe to register, and the event->id | |
405 | * stays unallocated. | |
406 | */ | |
407 | ret = add_pending_probe(event, event_param->name); | |
408 | if (ret) | |
409 | goto add_pending_error; | |
410 | } | |
8020ceb5 | 411 | break; |
8020ceb5 MD |
412 | default: |
413 | WARN_ON_ONCE(1); | |
414 | } | |
8165c8da MD |
415 | if (event->desc) { |
416 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); | |
417 | if (ret) | |
418 | goto statedump_error; | |
419 | } | |
b5234c06 | 420 | cds_list_add(&event->list, &chan->session->events); |
8020ceb5 MD |
421 | return event; |
422 | ||
423 | statedump_error: | |
8165c8da MD |
424 | if (event->desc) { |
425 | WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name, | |
426 | event->desc->probe_callback, | |
427 | event)); | |
428 | ltt_event_put(event->desc); | |
429 | } | |
430 | add_pending_error: | |
8020ceb5 | 431 | register_error: |
b5234c06 | 432 | free(event); |
8020ceb5 MD |
433 | cache_error: |
434 | exist: | |
435 | full: | |
8020ceb5 MD |
436 | return NULL; |
437 | } | |
438 | ||
439 | /* | |
440 | * Only used internally at session destruction. | |
441 | */ | |
442 | int _ltt_event_unregister(struct ltt_event *event) | |
443 | { | |
444 | int ret = -EINVAL; | |
445 | ||
446 | switch (event->instrumentation) { | |
b5234c06 | 447 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
448 | if (event->desc) { |
449 | ret = __tracepoint_probe_unregister(event->desc->name, | |
450 | event->desc->probe_callback, | |
451 | event); | |
452 | if (ret) | |
453 | return ret; | |
454 | } else { | |
455 | remove_pending_probe(event->pending_probe); | |
456 | ret = 0; | |
457 | } | |
8020ceb5 | 458 | break; |
8020ceb5 MD |
459 | default: |
460 | WARN_ON_ONCE(1); | |
461 | } | |
462 | return ret; | |
463 | } | |
464 | ||
465 | /* | |
466 | * Only used internally at session destruction. | |
467 | */ | |
468 | static | |
469 | void _ltt_event_destroy(struct ltt_event *event) | |
470 | { | |
471 | switch (event->instrumentation) { | |
b5234c06 | 472 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
473 | if (event->desc) { |
474 | ltt_event_put(event->desc); | |
475 | } | |
8020ceb5 | 476 | break; |
8020ceb5 MD |
477 | default: |
478 | WARN_ON_ONCE(1); | |
479 | } | |
b5234c06 | 480 | cds_list_del(&event->list); |
8020ceb5 | 481 | lttng_destroy_context(event->ctx); |
b5234c06 | 482 | free(event); |
8020ceb5 MD |
483 | } |
484 | ||
485 | /* | |
486 | * We have exclusive access to our metadata buffer (protected by the | |
17dfb34b | 487 | * ust_lock), so we can do racy operations such as looking for |
8020ceb5 MD |
488 | * remaining space left in packet and write, since mutual exclusion |
489 | * protects us from concurrent writes. | |
490 | */ | |
491 | int lttng_metadata_printf(struct ltt_session *session, | |
492 | const char *fmt, ...) | |
493 | { | |
494 | struct lib_ring_buffer_ctx ctx; | |
495 | struct ltt_channel *chan = session->metadata; | |
b5234c06 | 496 | char *str = NULL; |
8020ceb5 MD |
497 | int ret = 0, waitret; |
498 | size_t len, reserve_len, pos; | |
499 | va_list ap; | |
500 | ||
b5234c06 | 501 | WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active)); |
8020ceb5 MD |
502 | |
503 | va_start(ap, fmt); | |
b5234c06 | 504 | ret = vasprintf(&str, fmt, ap); |
8020ceb5 | 505 | va_end(ap); |
b5234c06 | 506 | if (ret < 0) |
8020ceb5 MD |
507 | return -ENOMEM; |
508 | ||
509 | len = strlen(str); | |
510 | pos = 0; | |
511 | ||
512 | for (pos = 0; pos < len; pos += reserve_len) { | |
513 | reserve_len = min_t(size_t, | |
1d498196 | 514 | chan->ops->packet_avail_size(chan->chan, chan->handle), |
8020ceb5 MD |
515 | len - pos); |
516 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, | |
1d498196 | 517 | sizeof(char), -1, chan->handle); |
8020ceb5 MD |
518 | /* |
519 | * We don't care about metadata buffer's records lost | |
520 | * count, because we always retry here. Report error if | |
521 | * we need to bail out after timeout or being | |
522 | * interrupted. | |
523 | */ | |
b5234c06 | 524 | waitret = wait_cond_interruptible_timeout( |
8020ceb5 MD |
525 | ({ |
526 | ret = chan->ops->event_reserve(&ctx, 0); | |
527 | ret != -ENOBUFS || !ret; | |
528 | }), | |
b5234c06 | 529 | LTTNG_METADATA_TIMEOUT_MSEC); |
b472cfc0 | 530 | if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) { |
b5234c06 MD |
531 | DBG("LTTng: Failure to write metadata to buffers (%s)\n", |
532 | waitret == -EINTR ? "interrupted" : | |
8020ceb5 | 533 | (ret == -ENOBUFS ? "timeout" : "I/O error")); |
b5234c06 | 534 | if (waitret == -EINTR) |
8020ceb5 MD |
535 | ret = waitret; |
536 | goto end; | |
537 | } | |
538 | chan->ops->event_write(&ctx, &str[pos], reserve_len); | |
539 | chan->ops->event_commit(&ctx); | |
540 | } | |
541 | end: | |
b5234c06 | 542 | free(str); |
8020ceb5 MD |
543 | return ret; |
544 | } | |
545 | ||
546 | static | |
547 | int _ltt_field_statedump(struct ltt_session *session, | |
548 | const struct lttng_event_field *field) | |
549 | { | |
550 | int ret = 0; | |
551 | ||
552 | switch (field->type.atype) { | |
553 | case atype_integer: | |
554 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 555 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8020ceb5 MD |
556 | field->type.u.basic.integer.size, |
557 | field->type.u.basic.integer.alignment, | |
558 | field->type.u.basic.integer.signedness, | |
559 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
560 | ? "none" | |
561 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
562 | ? "UTF8" | |
563 | : "ASCII", | |
564 | field->type.u.basic.integer.base, | |
403c40b4 MD |
565 | #ifdef __BIG_ENDIAN |
566 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", | |
567 | #else | |
568 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
569 | #endif | |
570 | field->name); | |
571 | break; | |
572 | case atype_float: | |
573 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 574 | " floating_point { exp_dig = %u; mant_dig = %u; align = %u; } _%s;\n", |
403c40b4 MD |
575 | field->type.u.basic._float.exp_dig, |
576 | field->type.u.basic._float.mant_dig, | |
577 | field->type.u.basic._float.alignment, | |
578 | #ifdef __BIG_ENDIAN | |
8020ceb5 MD |
579 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
580 | #else | |
581 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
582 | #endif | |
583 | field->name); | |
584 | break; | |
585 | case atype_enum: | |
586 | ret = lttng_metadata_printf(session, | |
587 | " %s %s;\n", | |
588 | field->type.u.basic.enumeration.name, | |
589 | field->name); | |
590 | break; | |
591 | case atype_array: | |
592 | { | |
593 | const struct lttng_basic_type *elem_type; | |
594 | ||
595 | elem_type = &field->type.u.array.elem_type; | |
596 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 597 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8020ceb5 MD |
598 | elem_type->u.basic.integer.size, |
599 | elem_type->u.basic.integer.alignment, | |
600 | elem_type->u.basic.integer.signedness, | |
601 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
602 | ? "none" | |
603 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
604 | ? "UTF8" | |
605 | : "ASCII", | |
606 | elem_type->u.basic.integer.base, | |
403c40b4 | 607 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
608 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
609 | #else | |
610 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
611 | #endif | |
612 | field->name, field->type.u.array.length); | |
613 | break; | |
614 | } | |
615 | case atype_sequence: | |
616 | { | |
617 | const struct lttng_basic_type *elem_type; | |
618 | const struct lttng_basic_type *length_type; | |
619 | ||
620 | elem_type = &field->type.u.sequence.elem_type; | |
621 | length_type = &field->type.u.sequence.length_type; | |
622 | ret = lttng_metadata_printf(session, | |
623 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
624 | length_type->u.basic.integer.size, | |
625 | (unsigned int) length_type->u.basic.integer.alignment, | |
626 | length_type->u.basic.integer.signedness, | |
627 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
628 | ? "none" | |
629 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
630 | ? "UTF8" | |
631 | : "ASCII"), | |
632 | length_type->u.basic.integer.base, | |
403c40b4 | 633 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
634 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
635 | #else | |
636 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
637 | #endif | |
638 | field->name); | |
639 | if (ret) | |
640 | return ret; | |
641 | ||
642 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 643 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8020ceb5 MD |
644 | elem_type->u.basic.integer.size, |
645 | (unsigned int) elem_type->u.basic.integer.alignment, | |
646 | elem_type->u.basic.integer.signedness, | |
647 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
648 | ? "none" | |
649 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
650 | ? "UTF8" | |
651 | : "ASCII"), | |
652 | elem_type->u.basic.integer.base, | |
403c40b4 | 653 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
654 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
655 | #else | |
656 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
657 | #endif | |
658 | field->name, | |
659 | field->name); | |
660 | break; | |
661 | } | |
662 | ||
663 | case atype_string: | |
664 | /* Default encoding is UTF8 */ | |
665 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 666 | " string%s _%s;\n", |
8020ceb5 MD |
667 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
668 | " { encoding = ASCII; }" : "", | |
669 | field->name); | |
670 | break; | |
671 | default: | |
672 | WARN_ON_ONCE(1); | |
673 | return -EINVAL; | |
674 | } | |
675 | return ret; | |
676 | } | |
677 | ||
678 | static | |
679 | int _ltt_context_metadata_statedump(struct ltt_session *session, | |
680 | struct lttng_ctx *ctx) | |
681 | { | |
682 | int ret = 0; | |
683 | int i; | |
684 | ||
685 | if (!ctx) | |
686 | return 0; | |
687 | for (i = 0; i < ctx->nr_fields; i++) { | |
688 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
689 | ||
690 | ret = _ltt_field_statedump(session, &field->event_field); | |
691 | if (ret) | |
692 | return ret; | |
693 | } | |
694 | return ret; | |
695 | } | |
696 | ||
697 | static | |
698 | int _ltt_fields_metadata_statedump(struct ltt_session *session, | |
699 | struct ltt_event *event) | |
700 | { | |
701 | const struct lttng_event_desc *desc = event->desc; | |
702 | int ret = 0; | |
703 | int i; | |
704 | ||
705 | for (i = 0; i < desc->nr_fields; i++) { | |
706 | const struct lttng_event_field *field = &desc->fields[i]; | |
707 | ||
708 | ret = _ltt_field_statedump(session, field); | |
709 | if (ret) | |
710 | return ret; | |
711 | } | |
712 | return ret; | |
713 | } | |
714 | ||
715 | static | |
716 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
717 | struct ltt_channel *chan, | |
718 | struct ltt_event *event) | |
719 | { | |
720 | int ret = 0; | |
721 | ||
b5234c06 | 722 | if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
723 | return 0; |
724 | if (chan == session->metadata) | |
725 | return 0; | |
8165c8da MD |
726 | /* |
727 | * Don't print events for which probe load is pending. | |
728 | */ | |
729 | if (!event->desc) | |
730 | return 0; | |
8020ceb5 MD |
731 | |
732 | ret = lttng_metadata_printf(session, | |
733 | "event {\n" | |
734 | " name = %s;\n" | |
735 | " id = %u;\n" | |
736 | " stream_id = %u;\n", | |
737 | event->desc->name, | |
738 | event->id, | |
739 | event->chan->id); | |
740 | if (ret) | |
741 | goto end; | |
742 | ||
743 | if (event->ctx) { | |
744 | ret = lttng_metadata_printf(session, | |
745 | " context := struct {\n"); | |
746 | if (ret) | |
747 | goto end; | |
748 | } | |
749 | ret = _ltt_context_metadata_statedump(session, event->ctx); | |
750 | if (ret) | |
751 | goto end; | |
752 | if (event->ctx) { | |
753 | ret = lttng_metadata_printf(session, | |
754 | " };\n"); | |
755 | if (ret) | |
756 | goto end; | |
757 | } | |
758 | ||
759 | ret = lttng_metadata_printf(session, | |
760 | " fields := struct {\n" | |
761 | ); | |
762 | if (ret) | |
763 | goto end; | |
764 | ||
765 | ret = _ltt_fields_metadata_statedump(session, event); | |
766 | if (ret) | |
767 | goto end; | |
768 | ||
769 | /* | |
770 | * LTTng space reservation can only reserve multiples of the | |
771 | * byte size. | |
772 | */ | |
773 | ret = lttng_metadata_printf(session, | |
774 | " };\n" | |
775 | "};\n\n"); | |
776 | if (ret) | |
777 | goto end; | |
778 | ||
779 | event->metadata_dumped = 1; | |
780 | end: | |
781 | return ret; | |
782 | ||
783 | } | |
784 | ||
785 | static | |
786 | int _ltt_channel_metadata_statedump(struct ltt_session *session, | |
787 | struct ltt_channel *chan) | |
788 | { | |
789 | int ret = 0; | |
790 | ||
b5234c06 | 791 | if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
792 | return 0; |
793 | if (chan == session->metadata) | |
794 | return 0; | |
795 | ||
796 | WARN_ON_ONCE(!chan->header_type); | |
797 | ret = lttng_metadata_printf(session, | |
798 | "stream {\n" | |
799 | " id = %u;\n" | |
800 | " event.header := %s;\n" | |
801 | " packet.context := struct packet_context;\n", | |
802 | chan->id, | |
803 | chan->header_type == 1 ? "struct event_header_compact" : | |
804 | "struct event_header_large"); | |
805 | if (ret) | |
806 | goto end; | |
807 | ||
808 | if (chan->ctx) { | |
809 | ret = lttng_metadata_printf(session, | |
810 | " event.context := struct {\n"); | |
811 | if (ret) | |
812 | goto end; | |
813 | } | |
814 | ret = _ltt_context_metadata_statedump(session, chan->ctx); | |
815 | if (ret) | |
816 | goto end; | |
817 | if (chan->ctx) { | |
818 | ret = lttng_metadata_printf(session, | |
819 | " };\n"); | |
820 | if (ret) | |
821 | goto end; | |
822 | } | |
823 | ||
824 | ret = lttng_metadata_printf(session, | |
825 | "};\n\n"); | |
826 | ||
827 | chan->metadata_dumped = 1; | |
828 | end: | |
829 | return ret; | |
830 | } | |
831 | ||
832 | static | |
833 | int _ltt_stream_packet_context_declare(struct ltt_session *session) | |
834 | { | |
835 | return lttng_metadata_printf(session, | |
836 | "struct packet_context {\n" | |
837 | " uint64_t timestamp_begin;\n" | |
838 | " uint64_t timestamp_end;\n" | |
839 | " uint32_t events_discarded;\n" | |
840 | " uint32_t content_size;\n" | |
841 | " uint32_t packet_size;\n" | |
842 | " uint32_t cpu_id;\n" | |
843 | "};\n\n" | |
844 | ); | |
845 | } | |
846 | ||
847 | /* | |
848 | * Compact header: | |
849 | * id: range: 0 - 30. | |
850 | * id 31 is reserved to indicate an extended header. | |
851 | * | |
852 | * Large header: | |
853 | * id: range: 0 - 65534. | |
854 | * id 65535 is reserved to indicate an extended header. | |
855 | */ | |
856 | static | |
857 | int _ltt_event_header_declare(struct ltt_session *session) | |
858 | { | |
859 | return lttng_metadata_printf(session, | |
860 | "struct event_header_compact {\n" | |
861 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
862 | " variant <id> {\n" | |
863 | " struct {\n" | |
864 | " uint27_t timestamp;\n" | |
865 | " } compact;\n" | |
866 | " struct {\n" | |
867 | " uint32_t id;\n" | |
868 | " uint64_t timestamp;\n" | |
869 | " } extended;\n" | |
870 | " } v;\n" | |
871 | "} align(%u);\n" | |
872 | "\n" | |
873 | "struct event_header_large {\n" | |
874 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
875 | " variant <id> {\n" | |
876 | " struct {\n" | |
877 | " uint32_t timestamp;\n" | |
878 | " } compact;\n" | |
879 | " struct {\n" | |
880 | " uint32_t id;\n" | |
881 | " uint64_t timestamp;\n" | |
882 | " } extended;\n" | |
883 | " } v;\n" | |
884 | "} align(%u);\n\n", | |
1dbfff0c MD |
885 | lttng_alignof(uint32_t) * CHAR_BIT, |
886 | lttng_alignof(uint16_t) * CHAR_BIT | |
8020ceb5 MD |
887 | ); |
888 | } | |
889 | ||
890 | /* | |
891 | * Output metadata into this session's metadata buffers. | |
892 | */ | |
893 | static | |
894 | int _ltt_session_metadata_statedump(struct ltt_session *session) | |
895 | { | |
b5234c06 MD |
896 | unsigned char *uuid_c = session->uuid; |
897 | char uuid_s[37]; | |
8020ceb5 MD |
898 | struct ltt_channel *chan; |
899 | struct ltt_event *event; | |
900 | int ret = 0; | |
901 | ||
b5234c06 | 902 | if (!CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
903 | return 0; |
904 | if (session->metadata_dumped) | |
905 | goto skip_session; | |
906 | if (!session->metadata) { | |
b5234c06 | 907 | DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
8020ceb5 MD |
908 | return -EPERM; |
909 | } | |
910 | ||
911 | snprintf(uuid_s, sizeof(uuid_s), | |
912 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", | |
913 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
914 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
915 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
916 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
917 | ||
918 | ret = lttng_metadata_printf(session, | |
919 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" | |
920 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
921 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
922 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
923 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" | |
924 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
925 | "\n" | |
926 | "trace {\n" | |
927 | " major = %u;\n" | |
928 | " minor = %u;\n" | |
929 | " uuid = \"%s\";\n" | |
930 | " byte_order = %s;\n" | |
931 | " packet.header := struct {\n" | |
932 | " uint32_t magic;\n" | |
933 | " uint8_t uuid[16];\n" | |
934 | " uint32_t stream_id;\n" | |
935 | " };\n" | |
936 | "};\n\n", | |
1dbfff0c MD |
937 | lttng_alignof(uint8_t) * CHAR_BIT, |
938 | lttng_alignof(uint16_t) * CHAR_BIT, | |
939 | lttng_alignof(uint32_t) * CHAR_BIT, | |
940 | lttng_alignof(uint64_t) * CHAR_BIT, | |
8020ceb5 MD |
941 | CTF_VERSION_MAJOR, |
942 | CTF_VERSION_MINOR, | |
943 | uuid_s, | |
403c40b4 | 944 | #ifdef __BIG_ENDIAN |
8020ceb5 MD |
945 | "be" |
946 | #else | |
947 | "le" | |
948 | #endif | |
949 | ); | |
950 | if (ret) | |
951 | goto end; | |
952 | ||
953 | ret = _ltt_stream_packet_context_declare(session); | |
954 | if (ret) | |
955 | goto end; | |
956 | ||
957 | ret = _ltt_event_header_declare(session); | |
958 | if (ret) | |
959 | goto end; | |
960 | ||
961 | skip_session: | |
b5234c06 | 962 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
963 | ret = _ltt_channel_metadata_statedump(session, chan); |
964 | if (ret) | |
965 | goto end; | |
966 | } | |
967 | ||
b5234c06 | 968 | cds_list_for_each_entry(event, &session->events, list) { |
8020ceb5 MD |
969 | ret = _ltt_event_metadata_statedump(session, event->chan, event); |
970 | if (ret) | |
971 | goto end; | |
972 | } | |
973 | session->metadata_dumped = 1; | |
974 | end: | |
975 | return ret; | |
976 | } | |
977 | ||
978 | /** | |
979 | * ltt_transport_register - LTT transport registration | |
980 | * @transport: transport structure | |
981 | * | |
982 | * Registers a transport which can be used as output to extract the data out of | |
17dfb34b | 983 | * LTTng. Called with ust_lock held. |
8020ceb5 MD |
984 | */ |
985 | void ltt_transport_register(struct ltt_transport *transport) | |
986 | { | |
b5234c06 | 987 | cds_list_add_tail(&transport->node, <t_transport_list); |
8020ceb5 | 988 | } |
8020ceb5 MD |
989 | |
990 | /** | |
991 | * ltt_transport_unregister - LTT transport unregistration | |
992 | * @transport: transport structure | |
17dfb34b | 993 | * Called with ust_lock held. |
8020ceb5 MD |
994 | */ |
995 | void ltt_transport_unregister(struct ltt_transport *transport) | |
996 | { | |
b5234c06 | 997 | cds_list_del(&transport->node); |
8020ceb5 MD |
998 | } |
999 | ||
1ea11eab | 1000 | void ltt_events_exit(void) |
8020ceb5 MD |
1001 | { |
1002 | struct ltt_session *session, *tmpsession; | |
1003 | ||
b5234c06 | 1004 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, list) |
8020ceb5 | 1005 | ltt_session_destroy(session); |
8020ceb5 | 1006 | } |