Commit | Line | Data |
---|---|---|
8020ceb5 MD |
1 | /* |
2 | * ltt-events.c | |
3 | * | |
4 | * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * Holds LTTng per-session event registry. | |
7 | * | |
8 | * Dual LGPL v2.1/GPL v2 license. | |
9 | */ | |
10 | ||
b5234c06 MD |
11 | #define _GNU_SOURCE |
12 | #include <stdio.h> | |
8a98a75d | 13 | #include <endian.h> |
b5234c06 | 14 | #include <urcu/list.h> |
8165c8da | 15 | #include <urcu/hlist.h> |
b5234c06 | 16 | #include <pthread.h> |
b5234c06 | 17 | #include <uuid/uuid.h> |
b5234c06 | 18 | #include <errno.h> |
f4681817 MD |
19 | #include <sys/shm.h> |
20 | #include <sys/ipc.h> | |
44c72f10 MD |
21 | #include <stdint.h> |
22 | #include <stddef.h> | |
23 | ||
24 | #include <urcu-bp.h> | |
25 | #include <urcu/compiler.h> | |
26 | #include <urcu/uatomic.h> | |
27 | #include <urcu/arch.h> | |
28 | ||
29 | #include <lttng/tracepoint.h> | |
4318ae1b | 30 | #include <lttng/ust-events.h> |
44c72f10 MD |
31 | |
32 | #include <usterr-signal-safe.h> | |
33 | #include <helper.h> | |
1f18504e | 34 | #include "error.h" |
44c72f10 | 35 | |
8020ceb5 | 36 | #include "ltt-tracer.h" |
8165c8da | 37 | #include "ltt-tracer-core.h" |
b728d87e | 38 | #include "wait.h" |
8d8a24c8 | 39 | #include "../libringbuffer/shm.h" |
596c4223 | 40 | #include "jhash.h" |
8165c8da MD |
41 | |
42 | /* | |
43 | * The sessions mutex is the centralized mutex across UST tracing | |
17dfb34b MD |
44 | * control and probe registration. All operations within this file are |
45 | * called by the communication thread, under ust_lock protection. | |
8165c8da | 46 | */ |
2b2d6ff7 | 47 | static pthread_mutex_t sessions_mutex = PTHREAD_MUTEX_INITIALIZER; |
8165c8da | 48 | |
17dfb34b | 49 | void ust_lock(void) |
8165c8da MD |
50 | { |
51 | pthread_mutex_lock(&sessions_mutex); | |
52 | } | |
53 | ||
17dfb34b | 54 | void ust_unlock(void) |
8165c8da MD |
55 | { |
56 | pthread_mutex_unlock(&sessions_mutex); | |
57 | } | |
58 | ||
b5234c06 | 59 | static CDS_LIST_HEAD(sessions); |
8165c8da MD |
60 | |
61 | /* | |
62 | * Pending probes hash table, containing the registered ltt events for | |
63 | * which tracepoint probes are still missing. Protected by the sessions | |
64 | * mutex. | |
65 | */ | |
66 | #define PENDING_PROBE_HASH_BITS 6 | |
67 | #define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS) | |
68 | static struct cds_hlist_head pending_probe_table[PENDING_PROBE_HASH_SIZE]; | |
69 | ||
70 | struct ust_pending_probe { | |
71 | struct ltt_event *event; | |
72 | struct cds_hlist_node node; | |
73 | char name[]; | |
74 | }; | |
8020ceb5 MD |
75 | |
76 | static void _ltt_event_destroy(struct ltt_event *event); | |
574a6217 | 77 | static void _ltt_loglevel_destroy(struct session_loglevel *sl); |
8020ceb5 MD |
78 | static void _ltt_channel_destroy(struct ltt_channel *chan); |
79 | static int _ltt_event_unregister(struct ltt_event *event); | |
80 | static | |
81 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
82 | struct ltt_channel *chan, | |
83 | struct ltt_event *event); | |
84 | static | |
85 | int _ltt_session_metadata_statedump(struct ltt_session *session); | |
86 | ||
8165c8da MD |
87 | /* |
88 | * called at event creation if probe is missing. | |
89 | * called with session mutex held. | |
90 | */ | |
91 | static | |
92 | int add_pending_probe(struct ltt_event *event, const char *name) | |
93 | { | |
94 | struct cds_hlist_head *head; | |
8165c8da MD |
95 | struct ust_pending_probe *e; |
96 | size_t name_len = strlen(name) + 1; | |
23c8854a | 97 | uint32_t hash = jhash(name, name_len - 1, 0); |
8165c8da MD |
98 | |
99 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; | |
100 | e = zmalloc(sizeof(struct ust_pending_probe) + name_len); | |
101 | if (!e) | |
102 | return -ENOMEM; | |
103 | memcpy(&e->name[0], name, name_len); | |
104 | cds_hlist_add_head(&e->node, head); | |
105 | e->event = event; | |
106 | event->pending_probe = e; | |
107 | return 0; | |
108 | } | |
109 | ||
110 | /* | |
111 | * remove a pending probe. called when at event teardown and when an | |
112 | * event is fixed (probe is loaded). | |
113 | * called with session mutex held. | |
114 | */ | |
115 | static | |
116 | void remove_pending_probe(struct ust_pending_probe *e) | |
117 | { | |
118 | if (!e) | |
119 | return; | |
120 | cds_hlist_del(&e->node); | |
121 | free(e); | |
122 | } | |
123 | ||
124 | /* | |
125 | * Called at library load: connect the probe on the events pending on | |
126 | * probe load. | |
127 | * called with session mutex held. | |
128 | */ | |
129 | int pending_probe_fix_events(const struct lttng_event_desc *desc) | |
130 | { | |
131 | struct cds_hlist_head *head; | |
132 | struct cds_hlist_node *node, *p; | |
133 | struct ust_pending_probe *e; | |
134 | const char *name = desc->name; | |
135 | size_t name_len = strlen(name) + 1; | |
23c8854a | 136 | uint32_t hash = jhash(name, name_len - 1, 0); |
8165c8da MD |
137 | int ret = 0; |
138 | ||
574a6217 | 139 | /* |
1f18504e MD |
140 | * For this event, we need to lookup the loglevel. If active (in |
141 | * the active loglevels hash table), we must create the event. | |
142 | */ | |
574a6217 MD |
143 | if (desc->loglevel) { |
144 | const struct tracepoint_loglevel_entry *ev_ll; | |
145 | struct loglevel_entry *loglevel; | |
146 | ||
147 | ev_ll = *desc->loglevel; | |
148 | loglevel = get_loglevel(ev_ll->identifier); | |
149 | if (loglevel) { | |
150 | struct session_loglevel *sl; | |
151 | ||
152 | cds_list_for_each_entry(sl, &loglevel->session_list, | |
153 | session_list) { | |
154 | struct ltt_event *ev; | |
155 | int ret; | |
156 | ||
157 | /* create event */ | |
158 | ret = ltt_event_create(sl->chan, | |
159 | &sl->event_param, NULL, | |
160 | &ev); | |
161 | /* | |
162 | * TODO: report error. | |
163 | */ | |
164 | if (ret) | |
165 | continue; | |
166 | cds_list_add(&ev->loglevel_list, | |
167 | &sl->events); | |
168 | } | |
169 | } | |
170 | } | |
1f18504e | 171 | |
8165c8da MD |
172 | head = &pending_probe_table[hash & (PENDING_PROBE_HASH_SIZE - 1)]; |
173 | cds_hlist_for_each_entry_safe(e, node, p, head, node) { | |
174 | struct ltt_event *event; | |
175 | struct ltt_channel *chan; | |
176 | ||
177 | if (strcmp(name, e->name)) | |
178 | continue; | |
179 | event = e->event; | |
180 | chan = event->chan; | |
181 | assert(!event->desc); | |
182 | event->desc = desc; | |
183 | event->pending_probe = NULL; | |
184 | remove_pending_probe(e); | |
185 | ret |= __tracepoint_probe_register(name, | |
186 | event->desc->probe_callback, | |
187 | event); | |
636c5aa4 MD |
188 | if (ret) |
189 | continue; | |
190 | event->id = chan->free_event_id++; | |
8165c8da MD |
191 | ret |= _ltt_event_metadata_statedump(chan->session, chan, |
192 | event); | |
193 | } | |
194 | return ret; | |
195 | } | |
196 | ||
8020ceb5 MD |
197 | void synchronize_trace(void) |
198 | { | |
8020ceb5 | 199 | synchronize_rcu(); |
8020ceb5 MD |
200 | } |
201 | ||
202 | struct ltt_session *ltt_session_create(void) | |
203 | { | |
204 | struct ltt_session *session; | |
205 | ||
b5234c06 | 206 | session = zmalloc(sizeof(struct ltt_session)); |
8020ceb5 MD |
207 | if (!session) |
208 | return NULL; | |
b5234c06 MD |
209 | CDS_INIT_LIST_HEAD(&session->chan); |
210 | CDS_INIT_LIST_HEAD(&session->events); | |
1f18504e | 211 | CDS_INIT_LIST_HEAD(&session->loglevels); |
b5234c06 MD |
212 | uuid_generate(session->uuid); |
213 | cds_list_add(&session->list, &sessions); | |
8020ceb5 MD |
214 | return session; |
215 | } | |
216 | ||
217 | void ltt_session_destroy(struct ltt_session *session) | |
218 | { | |
219 | struct ltt_channel *chan, *tmpchan; | |
220 | struct ltt_event *event, *tmpevent; | |
574a6217 | 221 | struct session_loglevel *loglevel, *tmploglevel; |
8020ceb5 MD |
222 | int ret; |
223 | ||
b5234c06 MD |
224 | CMM_ACCESS_ONCE(session->active) = 0; |
225 | cds_list_for_each_entry(event, &session->events, list) { | |
8020ceb5 MD |
226 | ret = _ltt_event_unregister(event); |
227 | WARN_ON(ret); | |
228 | } | |
229 | synchronize_trace(); /* Wait for in-flight events to complete */ | |
1f18504e MD |
230 | cds_list_for_each_entry_safe(loglevel, tmploglevel, &session->loglevels, list) |
231 | _ltt_loglevel_destroy(loglevel); | |
b5234c06 | 232 | cds_list_for_each_entry_safe(event, tmpevent, &session->events, list) |
8020ceb5 | 233 | _ltt_event_destroy(event); |
b5234c06 | 234 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan, list) |
8020ceb5 | 235 | _ltt_channel_destroy(chan); |
b5234c06 | 236 | cds_list_del(&session->list); |
b5234c06 | 237 | free(session); |
8020ceb5 MD |
238 | } |
239 | ||
976fe9ea | 240 | int ltt_session_enable(struct ltt_session *session) |
8020ceb5 MD |
241 | { |
242 | int ret = 0; | |
243 | struct ltt_channel *chan; | |
244 | ||
8020ceb5 MD |
245 | if (session->active) { |
246 | ret = -EBUSY; | |
247 | goto end; | |
248 | } | |
249 | ||
250 | /* | |
251 | * Snapshot the number of events per channel to know the type of header | |
252 | * we need to use. | |
253 | */ | |
b5234c06 | 254 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
255 | if (chan->header_type) |
256 | continue; /* don't change it if session stop/restart */ | |
257 | if (chan->free_event_id < 31) | |
258 | chan->header_type = 1; /* compact */ | |
259 | else | |
260 | chan->header_type = 2; /* large */ | |
261 | } | |
262 | ||
b5234c06 MD |
263 | CMM_ACCESS_ONCE(session->active) = 1; |
264 | CMM_ACCESS_ONCE(session->been_active) = 1; | |
8020ceb5 | 265 | ret = _ltt_session_metadata_statedump(session); |
4b4de73e | 266 | if (ret) |
b5234c06 | 267 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 268 | end: |
8020ceb5 MD |
269 | return ret; |
270 | } | |
271 | ||
976fe9ea | 272 | int ltt_session_disable(struct ltt_session *session) |
8020ceb5 MD |
273 | { |
274 | int ret = 0; | |
275 | ||
8020ceb5 MD |
276 | if (!session->active) { |
277 | ret = -EBUSY; | |
278 | goto end; | |
279 | } | |
b5234c06 | 280 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 281 | end: |
8020ceb5 MD |
282 | return ret; |
283 | } | |
284 | ||
976fe9ea MD |
285 | int ltt_channel_enable(struct ltt_channel *channel) |
286 | { | |
287 | int old; | |
288 | ||
9beb36ba MD |
289 | if (channel == channel->session->metadata) |
290 | return -EPERM; | |
b5234c06 | 291 | old = uatomic_xchg(&channel->enabled, 1); |
976fe9ea MD |
292 | if (old) |
293 | return -EEXIST; | |
294 | return 0; | |
295 | } | |
296 | ||
297 | int ltt_channel_disable(struct ltt_channel *channel) | |
298 | { | |
299 | int old; | |
300 | ||
9beb36ba MD |
301 | if (channel == channel->session->metadata) |
302 | return -EPERM; | |
b5234c06 | 303 | old = uatomic_xchg(&channel->enabled, 0); |
976fe9ea MD |
304 | if (!old) |
305 | return -EEXIST; | |
306 | return 0; | |
307 | } | |
308 | ||
309 | int ltt_event_enable(struct ltt_event *event) | |
310 | { | |
311 | int old; | |
312 | ||
9beb36ba MD |
313 | if (event->chan == event->chan->session->metadata) |
314 | return -EPERM; | |
b5234c06 | 315 | old = uatomic_xchg(&event->enabled, 1); |
976fe9ea MD |
316 | if (old) |
317 | return -EEXIST; | |
318 | return 0; | |
319 | } | |
320 | ||
321 | int ltt_event_disable(struct ltt_event *event) | |
322 | { | |
323 | int old; | |
324 | ||
9beb36ba MD |
325 | if (event->chan == event->chan->session->metadata) |
326 | return -EPERM; | |
b5234c06 | 327 | old = uatomic_xchg(&event->enabled, 0); |
976fe9ea MD |
328 | if (!old) |
329 | return -EEXIST; | |
330 | return 0; | |
331 | } | |
332 | ||
8020ceb5 MD |
333 | struct ltt_channel *ltt_channel_create(struct ltt_session *session, |
334 | const char *transport_name, | |
335 | void *buf_addr, | |
336 | size_t subbuf_size, size_t num_subbuf, | |
337 | unsigned int switch_timer_interval, | |
193183fb MD |
338 | unsigned int read_timer_interval, |
339 | int *shm_fd, int *wait_fd, | |
d028eddb MD |
340 | uint64_t *memory_map_size, |
341 | struct ltt_channel *chan_priv_init) | |
8020ceb5 | 342 | { |
a3f61e7f | 343 | struct ltt_channel *chan = NULL; |
8020ceb5 MD |
344 | struct ltt_transport *transport; |
345 | ||
8020ceb5 MD |
346 | if (session->been_active) |
347 | goto active; /* Refuse to add channel to active session */ | |
348 | transport = ltt_transport_find(transport_name); | |
349 | if (!transport) { | |
b5234c06 | 350 | DBG("LTTng transport %s not found\n", |
8020ceb5 MD |
351 | transport_name); |
352 | goto notransport; | |
353 | } | |
d028eddb MD |
354 | chan_priv_init->id = session->free_chan_id++; |
355 | chan_priv_init->session = session; | |
8020ceb5 MD |
356 | /* |
357 | * Note: the channel creation op already writes into the packet | |
358 | * headers. Therefore the "chan" information used as input | |
359 | * should be already accessible. | |
360 | */ | |
a3f61e7f | 361 | chan = transport->ops.channel_create("[lttng]", buf_addr, |
8020ceb5 | 362 | subbuf_size, num_subbuf, switch_timer_interval, |
193183fb | 363 | read_timer_interval, shm_fd, wait_fd, |
d028eddb | 364 | memory_map_size, chan_priv_init); |
a3f61e7f | 365 | if (!chan) |
8020ceb5 | 366 | goto create_error; |
976fe9ea | 367 | chan->enabled = 1; |
8020ceb5 | 368 | chan->ops = &transport->ops; |
b5234c06 | 369 | cds_list_add(&chan->list, &session->chan); |
8020ceb5 MD |
370 | return chan; |
371 | ||
372 | create_error: | |
8020ceb5 MD |
373 | notransport: |
374 | active: | |
8020ceb5 MD |
375 | return NULL; |
376 | } | |
377 | ||
378 | /* | |
379 | * Only used internally at session destruction. | |
380 | */ | |
381 | static | |
382 | void _ltt_channel_destroy(struct ltt_channel *chan) | |
383 | { | |
b5234c06 | 384 | cds_list_del(&chan->list); |
8020ceb5 | 385 | lttng_destroy_context(chan->ctx); |
a3f61e7f | 386 | chan->ops->channel_destroy(chan); |
8020ceb5 MD |
387 | } |
388 | ||
1f18504e MD |
389 | int ltt_loglevel_create(struct ltt_channel *chan, |
390 | struct lttng_ust_event *event_param, | |
574a6217 | 391 | struct session_loglevel **_sl) |
1f18504e | 392 | { |
574a6217 | 393 | struct session_loglevel *sl; |
1f18504e | 394 | |
574a6217 MD |
395 | sl = add_loglevel(event_param->name, chan, event_param); |
396 | if (!sl || IS_ERR(sl)) { | |
397 | return PTR_ERR(sl); | |
1f18504e | 398 | } |
574a6217 | 399 | *_sl = sl; |
1f18504e MD |
400 | return 0; |
401 | } | |
402 | ||
403 | static | |
574a6217 | 404 | void _ltt_loglevel_destroy(struct session_loglevel *sl) |
1f18504e | 405 | { |
574a6217 | 406 | _remove_loglevel(sl); |
1f18504e MD |
407 | } |
408 | ||
8020ceb5 MD |
409 | /* |
410 | * Supports event creation while tracing session is active. | |
411 | */ | |
576599a0 MD |
412 | int ltt_event_create(struct ltt_channel *chan, |
413 | struct lttng_ust_event *event_param, | |
414 | void *filter, | |
415 | struct ltt_event **_event) | |
8020ceb5 MD |
416 | { |
417 | struct ltt_event *event; | |
576599a0 | 418 | int ret = 0; |
8020ceb5 | 419 | |
576599a0 MD |
420 | if (chan->used_event_id == -1UL) { |
421 | ret = -ENOMEM; | |
8020ceb5 | 422 | goto full; |
576599a0 | 423 | } |
8020ceb5 MD |
424 | /* |
425 | * This is O(n^2) (for each event, the loop is called at event | |
426 | * creation). Might require a hash if we have lots of events. | |
427 | */ | |
576599a0 MD |
428 | cds_list_for_each_entry(event, &chan->session->events, list) { |
429 | if (event->desc && !strcmp(event->desc->name, event_param->name)) { | |
430 | ret = -EEXIST; | |
8020ceb5 | 431 | goto exist; |
576599a0 MD |
432 | } |
433 | } | |
b5234c06 | 434 | event = zmalloc(sizeof(struct ltt_event)); |
576599a0 MD |
435 | if (!event) { |
436 | ret = -ENOMEM; | |
8020ceb5 | 437 | goto cache_error; |
576599a0 | 438 | } |
8020ceb5 MD |
439 | event->chan = chan; |
440 | event->filter = filter; | |
8165c8da MD |
441 | /* |
442 | * used_event_id counts the maximum number of event IDs that can | |
443 | * register if all probes register. | |
444 | */ | |
445 | chan->used_event_id++; | |
976fe9ea | 446 | event->enabled = 1; |
8020ceb5 MD |
447 | event->instrumentation = event_param->instrumentation; |
448 | /* Populate ltt_event structure before tracepoint registration. */ | |
b5234c06 | 449 | cmm_smp_wmb(); |
8020ceb5 | 450 | switch (event_param->instrumentation) { |
b5234c06 | 451 | case LTTNG_UST_TRACEPOINT: |
8020ceb5 | 452 | event->desc = ltt_event_get(event_param->name); |
8165c8da MD |
453 | if (event->desc) { |
454 | ret = __tracepoint_probe_register(event_param->name, | |
455 | event->desc->probe_callback, | |
456 | event); | |
457 | if (ret) | |
458 | goto register_error; | |
459 | event->id = chan->free_event_id++; | |
460 | } else { | |
461 | /* | |
462 | * If the probe is not present, event->desc stays NULL, | |
463 | * waiting for the probe to register, and the event->id | |
464 | * stays unallocated. | |
465 | */ | |
466 | ret = add_pending_probe(event, event_param->name); | |
467 | if (ret) | |
468 | goto add_pending_error; | |
469 | } | |
8020ceb5 | 470 | break; |
df854e41 | 471 | case LTTNG_UST_TRACEPOINT_LOGLEVEL: |
1f18504e | 472 | assert(0); |
df854e41 | 473 | break; |
8020ceb5 MD |
474 | default: |
475 | WARN_ON_ONCE(1); | |
476 | } | |
8165c8da MD |
477 | if (event->desc) { |
478 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); | |
479 | if (ret) | |
480 | goto statedump_error; | |
481 | } | |
b5234c06 | 482 | cds_list_add(&event->list, &chan->session->events); |
576599a0 MD |
483 | *_event = event; |
484 | return 0; | |
8020ceb5 MD |
485 | |
486 | statedump_error: | |
8165c8da MD |
487 | if (event->desc) { |
488 | WARN_ON_ONCE(__tracepoint_probe_unregister(event_param->name, | |
489 | event->desc->probe_callback, | |
490 | event)); | |
491 | ltt_event_put(event->desc); | |
492 | } | |
493 | add_pending_error: | |
8020ceb5 | 494 | register_error: |
b5234c06 | 495 | free(event); |
8020ceb5 MD |
496 | cache_error: |
497 | exist: | |
498 | full: | |
576599a0 | 499 | return ret; |
8020ceb5 MD |
500 | } |
501 | ||
502 | /* | |
503 | * Only used internally at session destruction. | |
504 | */ | |
505 | int _ltt_event_unregister(struct ltt_event *event) | |
506 | { | |
507 | int ret = -EINVAL; | |
508 | ||
509 | switch (event->instrumentation) { | |
b5234c06 | 510 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
511 | if (event->desc) { |
512 | ret = __tracepoint_probe_unregister(event->desc->name, | |
513 | event->desc->probe_callback, | |
514 | event); | |
515 | if (ret) | |
516 | return ret; | |
517 | } else { | |
518 | remove_pending_probe(event->pending_probe); | |
519 | ret = 0; | |
520 | } | |
8020ceb5 | 521 | break; |
8020ceb5 MD |
522 | default: |
523 | WARN_ON_ONCE(1); | |
524 | } | |
525 | return ret; | |
526 | } | |
527 | ||
528 | /* | |
529 | * Only used internally at session destruction. | |
530 | */ | |
531 | static | |
532 | void _ltt_event_destroy(struct ltt_event *event) | |
533 | { | |
534 | switch (event->instrumentation) { | |
b5234c06 | 535 | case LTTNG_UST_TRACEPOINT: |
8165c8da MD |
536 | if (event->desc) { |
537 | ltt_event_put(event->desc); | |
538 | } | |
8020ceb5 | 539 | break; |
8020ceb5 MD |
540 | default: |
541 | WARN_ON_ONCE(1); | |
542 | } | |
b5234c06 | 543 | cds_list_del(&event->list); |
8020ceb5 | 544 | lttng_destroy_context(event->ctx); |
b5234c06 | 545 | free(event); |
8020ceb5 MD |
546 | } |
547 | ||
548 | /* | |
549 | * We have exclusive access to our metadata buffer (protected by the | |
17dfb34b | 550 | * ust_lock), so we can do racy operations such as looking for |
8020ceb5 MD |
551 | * remaining space left in packet and write, since mutual exclusion |
552 | * protects us from concurrent writes. | |
553 | */ | |
554 | int lttng_metadata_printf(struct ltt_session *session, | |
555 | const char *fmt, ...) | |
556 | { | |
4cfec15c | 557 | struct lttng_ust_lib_ring_buffer_ctx ctx; |
8020ceb5 | 558 | struct ltt_channel *chan = session->metadata; |
b5234c06 | 559 | char *str = NULL; |
8020ceb5 MD |
560 | int ret = 0, waitret; |
561 | size_t len, reserve_len, pos; | |
562 | va_list ap; | |
563 | ||
b5234c06 | 564 | WARN_ON_ONCE(!CMM_ACCESS_ONCE(session->active)); |
8020ceb5 MD |
565 | |
566 | va_start(ap, fmt); | |
b5234c06 | 567 | ret = vasprintf(&str, fmt, ap); |
8020ceb5 | 568 | va_end(ap); |
b5234c06 | 569 | if (ret < 0) |
8020ceb5 MD |
570 | return -ENOMEM; |
571 | ||
572 | len = strlen(str); | |
573 | pos = 0; | |
574 | ||
575 | for (pos = 0; pos < len; pos += reserve_len) { | |
576 | reserve_len = min_t(size_t, | |
1d498196 | 577 | chan->ops->packet_avail_size(chan->chan, chan->handle), |
8020ceb5 MD |
578 | len - pos); |
579 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, | |
1d498196 | 580 | sizeof(char), -1, chan->handle); |
8020ceb5 MD |
581 | /* |
582 | * We don't care about metadata buffer's records lost | |
583 | * count, because we always retry here. Report error if | |
584 | * we need to bail out after timeout or being | |
585 | * interrupted. | |
586 | */ | |
b5234c06 | 587 | waitret = wait_cond_interruptible_timeout( |
8020ceb5 MD |
588 | ({ |
589 | ret = chan->ops->event_reserve(&ctx, 0); | |
590 | ret != -ENOBUFS || !ret; | |
591 | }), | |
b5234c06 | 592 | LTTNG_METADATA_TIMEOUT_MSEC); |
b472cfc0 | 593 | if (waitret == -ETIMEDOUT || waitret == -EINTR || ret) { |
b5234c06 MD |
594 | DBG("LTTng: Failure to write metadata to buffers (%s)\n", |
595 | waitret == -EINTR ? "interrupted" : | |
8020ceb5 | 596 | (ret == -ENOBUFS ? "timeout" : "I/O error")); |
b5234c06 | 597 | if (waitret == -EINTR) |
8020ceb5 MD |
598 | ret = waitret; |
599 | goto end; | |
600 | } | |
601 | chan->ops->event_write(&ctx, &str[pos], reserve_len); | |
602 | chan->ops->event_commit(&ctx); | |
603 | } | |
604 | end: | |
b5234c06 | 605 | free(str); |
8020ceb5 MD |
606 | return ret; |
607 | } | |
608 | ||
609 | static | |
610 | int _ltt_field_statedump(struct ltt_session *session, | |
611 | const struct lttng_event_field *field) | |
612 | { | |
613 | int ret = 0; | |
614 | ||
615 | switch (field->type.atype) { | |
616 | case atype_integer: | |
617 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 618 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8020ceb5 MD |
619 | field->type.u.basic.integer.size, |
620 | field->type.u.basic.integer.alignment, | |
621 | field->type.u.basic.integer.signedness, | |
622 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
623 | ? "none" | |
624 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
625 | ? "UTF8" | |
626 | : "ASCII", | |
627 | field->type.u.basic.integer.base, | |
8a98a75d | 628 | #if (BYTE_ORDER == BIG_ENDIAN) |
403c40b4 MD |
629 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
630 | #else | |
631 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
632 | #endif | |
633 | field->name); | |
634 | break; | |
635 | case atype_float: | |
636 | ret = lttng_metadata_printf(session, | |
8a98a75d | 637 | " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n", |
403c40b4 MD |
638 | field->type.u.basic._float.exp_dig, |
639 | field->type.u.basic._float.mant_dig, | |
640 | field->type.u.basic._float.alignment, | |
8a98a75d | 641 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
642 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
643 | #else | |
644 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
645 | #endif | |
646 | field->name); | |
647 | break; | |
648 | case atype_enum: | |
649 | ret = lttng_metadata_printf(session, | |
650 | " %s %s;\n", | |
651 | field->type.u.basic.enumeration.name, | |
652 | field->name); | |
653 | break; | |
654 | case atype_array: | |
655 | { | |
656 | const struct lttng_basic_type *elem_type; | |
657 | ||
658 | elem_type = &field->type.u.array.elem_type; | |
659 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 660 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8020ceb5 MD |
661 | elem_type->u.basic.integer.size, |
662 | elem_type->u.basic.integer.alignment, | |
663 | elem_type->u.basic.integer.signedness, | |
664 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
665 | ? "none" | |
666 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
667 | ? "UTF8" | |
668 | : "ASCII", | |
669 | elem_type->u.basic.integer.base, | |
8a98a75d | 670 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
671 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
672 | #else | |
673 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
674 | #endif | |
675 | field->name, field->type.u.array.length); | |
676 | break; | |
677 | } | |
678 | case atype_sequence: | |
679 | { | |
680 | const struct lttng_basic_type *elem_type; | |
681 | const struct lttng_basic_type *length_type; | |
682 | ||
683 | elem_type = &field->type.u.sequence.elem_type; | |
684 | length_type = &field->type.u.sequence.length_type; | |
685 | ret = lttng_metadata_printf(session, | |
686 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
687 | length_type->u.basic.integer.size, | |
688 | (unsigned int) length_type->u.basic.integer.alignment, | |
689 | length_type->u.basic.integer.signedness, | |
690 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
691 | ? "none" | |
692 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
693 | ? "UTF8" | |
694 | : "ASCII"), | |
695 | length_type->u.basic.integer.base, | |
8a98a75d | 696 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
697 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
698 | #else | |
699 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
700 | #endif | |
701 | field->name); | |
702 | if (ret) | |
703 | return ret; | |
704 | ||
705 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 706 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8020ceb5 MD |
707 | elem_type->u.basic.integer.size, |
708 | (unsigned int) elem_type->u.basic.integer.alignment, | |
709 | elem_type->u.basic.integer.signedness, | |
710 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
711 | ? "none" | |
712 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
713 | ? "UTF8" | |
714 | : "ASCII"), | |
715 | elem_type->u.basic.integer.base, | |
8a98a75d | 716 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
717 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
718 | #else | |
719 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
720 | #endif | |
721 | field->name, | |
722 | field->name); | |
723 | break; | |
724 | } | |
725 | ||
726 | case atype_string: | |
727 | /* Default encoding is UTF8 */ | |
728 | ret = lttng_metadata_printf(session, | |
4e2ee1f5 | 729 | " string%s _%s;\n", |
8020ceb5 MD |
730 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
731 | " { encoding = ASCII; }" : "", | |
732 | field->name); | |
733 | break; | |
734 | default: | |
735 | WARN_ON_ONCE(1); | |
736 | return -EINVAL; | |
737 | } | |
738 | return ret; | |
739 | } | |
740 | ||
741 | static | |
742 | int _ltt_context_metadata_statedump(struct ltt_session *session, | |
743 | struct lttng_ctx *ctx) | |
744 | { | |
745 | int ret = 0; | |
746 | int i; | |
747 | ||
748 | if (!ctx) | |
749 | return 0; | |
750 | for (i = 0; i < ctx->nr_fields; i++) { | |
751 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
752 | ||
753 | ret = _ltt_field_statedump(session, &field->event_field); | |
754 | if (ret) | |
755 | return ret; | |
756 | } | |
757 | return ret; | |
758 | } | |
759 | ||
760 | static | |
761 | int _ltt_fields_metadata_statedump(struct ltt_session *session, | |
762 | struct ltt_event *event) | |
763 | { | |
764 | const struct lttng_event_desc *desc = event->desc; | |
765 | int ret = 0; | |
766 | int i; | |
767 | ||
768 | for (i = 0; i < desc->nr_fields; i++) { | |
769 | const struct lttng_event_field *field = &desc->fields[i]; | |
770 | ||
771 | ret = _ltt_field_statedump(session, field); | |
772 | if (ret) | |
773 | return ret; | |
774 | } | |
775 | return ret; | |
776 | } | |
777 | ||
778 | static | |
779 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
780 | struct ltt_channel *chan, | |
781 | struct ltt_event *event) | |
782 | { | |
783 | int ret = 0; | |
784 | ||
b5234c06 | 785 | if (event->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
786 | return 0; |
787 | if (chan == session->metadata) | |
788 | return 0; | |
8165c8da MD |
789 | /* |
790 | * Don't print events for which probe load is pending. | |
791 | */ | |
792 | if (!event->desc) | |
793 | return 0; | |
8020ceb5 MD |
794 | |
795 | ret = lttng_metadata_printf(session, | |
796 | "event {\n" | |
7083f0fe | 797 | " name = \"%s\";\n" |
8020ceb5 MD |
798 | " id = %u;\n" |
799 | " stream_id = %u;\n", | |
800 | event->desc->name, | |
801 | event->id, | |
802 | event->chan->id); | |
803 | if (ret) | |
804 | goto end; | |
805 | ||
806 | if (event->ctx) { | |
807 | ret = lttng_metadata_printf(session, | |
808 | " context := struct {\n"); | |
809 | if (ret) | |
810 | goto end; | |
811 | } | |
812 | ret = _ltt_context_metadata_statedump(session, event->ctx); | |
813 | if (ret) | |
814 | goto end; | |
815 | if (event->ctx) { | |
816 | ret = lttng_metadata_printf(session, | |
817 | " };\n"); | |
818 | if (ret) | |
819 | goto end; | |
820 | } | |
821 | ||
822 | ret = lttng_metadata_printf(session, | |
823 | " fields := struct {\n" | |
824 | ); | |
825 | if (ret) | |
826 | goto end; | |
827 | ||
828 | ret = _ltt_fields_metadata_statedump(session, event); | |
829 | if (ret) | |
830 | goto end; | |
831 | ||
832 | /* | |
833 | * LTTng space reservation can only reserve multiples of the | |
834 | * byte size. | |
835 | */ | |
836 | ret = lttng_metadata_printf(session, | |
837 | " };\n" | |
838 | "};\n\n"); | |
839 | if (ret) | |
840 | goto end; | |
841 | ||
842 | event->metadata_dumped = 1; | |
843 | end: | |
844 | return ret; | |
845 | ||
846 | } | |
847 | ||
848 | static | |
849 | int _ltt_channel_metadata_statedump(struct ltt_session *session, | |
850 | struct ltt_channel *chan) | |
851 | { | |
852 | int ret = 0; | |
853 | ||
b5234c06 | 854 | if (chan->metadata_dumped || !CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
855 | return 0; |
856 | if (chan == session->metadata) | |
857 | return 0; | |
858 | ||
859 | WARN_ON_ONCE(!chan->header_type); | |
860 | ret = lttng_metadata_printf(session, | |
861 | "stream {\n" | |
862 | " id = %u;\n" | |
863 | " event.header := %s;\n" | |
864 | " packet.context := struct packet_context;\n", | |
865 | chan->id, | |
866 | chan->header_type == 1 ? "struct event_header_compact" : | |
867 | "struct event_header_large"); | |
868 | if (ret) | |
869 | goto end; | |
870 | ||
871 | if (chan->ctx) { | |
872 | ret = lttng_metadata_printf(session, | |
873 | " event.context := struct {\n"); | |
874 | if (ret) | |
875 | goto end; | |
876 | } | |
877 | ret = _ltt_context_metadata_statedump(session, chan->ctx); | |
878 | if (ret) | |
879 | goto end; | |
880 | if (chan->ctx) { | |
881 | ret = lttng_metadata_printf(session, | |
882 | " };\n"); | |
883 | if (ret) | |
884 | goto end; | |
885 | } | |
886 | ||
887 | ret = lttng_metadata_printf(session, | |
888 | "};\n\n"); | |
889 | ||
890 | chan->metadata_dumped = 1; | |
891 | end: | |
892 | return ret; | |
893 | } | |
894 | ||
895 | static | |
896 | int _ltt_stream_packet_context_declare(struct ltt_session *session) | |
897 | { | |
898 | return lttng_metadata_printf(session, | |
899 | "struct packet_context {\n" | |
900 | " uint64_t timestamp_begin;\n" | |
901 | " uint64_t timestamp_end;\n" | |
902 | " uint32_t events_discarded;\n" | |
903 | " uint32_t content_size;\n" | |
904 | " uint32_t packet_size;\n" | |
905 | " uint32_t cpu_id;\n" | |
906 | "};\n\n" | |
907 | ); | |
908 | } | |
909 | ||
910 | /* | |
911 | * Compact header: | |
912 | * id: range: 0 - 30. | |
913 | * id 31 is reserved to indicate an extended header. | |
914 | * | |
915 | * Large header: | |
916 | * id: range: 0 - 65534. | |
917 | * id 65535 is reserved to indicate an extended header. | |
918 | */ | |
919 | static | |
920 | int _ltt_event_header_declare(struct ltt_session *session) | |
921 | { | |
922 | return lttng_metadata_printf(session, | |
923 | "struct event_header_compact {\n" | |
924 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
925 | " variant <id> {\n" | |
926 | " struct {\n" | |
927 | " uint27_t timestamp;\n" | |
928 | " } compact;\n" | |
929 | " struct {\n" | |
930 | " uint32_t id;\n" | |
931 | " uint64_t timestamp;\n" | |
932 | " } extended;\n" | |
933 | " } v;\n" | |
934 | "} align(%u);\n" | |
935 | "\n" | |
936 | "struct event_header_large {\n" | |
937 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
938 | " variant <id> {\n" | |
939 | " struct {\n" | |
940 | " uint32_t timestamp;\n" | |
941 | " } compact;\n" | |
942 | " struct {\n" | |
943 | " uint32_t id;\n" | |
944 | " uint64_t timestamp;\n" | |
945 | " } extended;\n" | |
946 | " } v;\n" | |
947 | "} align(%u);\n\n", | |
1dbfff0c MD |
948 | lttng_alignof(uint32_t) * CHAR_BIT, |
949 | lttng_alignof(uint16_t) * CHAR_BIT | |
8020ceb5 MD |
950 | ); |
951 | } | |
952 | ||
953 | /* | |
954 | * Output metadata into this session's metadata buffers. | |
955 | */ | |
956 | static | |
957 | int _ltt_session_metadata_statedump(struct ltt_session *session) | |
958 | { | |
b5234c06 MD |
959 | unsigned char *uuid_c = session->uuid; |
960 | char uuid_s[37]; | |
8020ceb5 MD |
961 | struct ltt_channel *chan; |
962 | struct ltt_event *event; | |
963 | int ret = 0; | |
964 | ||
b5234c06 | 965 | if (!CMM_ACCESS_ONCE(session->active)) |
8020ceb5 MD |
966 | return 0; |
967 | if (session->metadata_dumped) | |
968 | goto skip_session; | |
969 | if (!session->metadata) { | |
b5234c06 | 970 | DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
8020ceb5 MD |
971 | return -EPERM; |
972 | } | |
973 | ||
974 | snprintf(uuid_s, sizeof(uuid_s), | |
975 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", | |
976 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
977 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
978 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
979 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
980 | ||
981 | ret = lttng_metadata_printf(session, | |
982 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" | |
983 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
984 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
985 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
986 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" | |
987 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
988 | "\n" | |
989 | "trace {\n" | |
990 | " major = %u;\n" | |
991 | " minor = %u;\n" | |
992 | " uuid = \"%s\";\n" | |
993 | " byte_order = %s;\n" | |
994 | " packet.header := struct {\n" | |
995 | " uint32_t magic;\n" | |
996 | " uint8_t uuid[16];\n" | |
997 | " uint32_t stream_id;\n" | |
998 | " };\n" | |
999 | "};\n\n", | |
1dbfff0c MD |
1000 | lttng_alignof(uint8_t) * CHAR_BIT, |
1001 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1002 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1003 | lttng_alignof(uint64_t) * CHAR_BIT, | |
8020ceb5 MD |
1004 | CTF_VERSION_MAJOR, |
1005 | CTF_VERSION_MINOR, | |
1006 | uuid_s, | |
8a98a75d | 1007 | #if (BYTE_ORDER == BIG_ENDIAN) |
8020ceb5 MD |
1008 | "be" |
1009 | #else | |
1010 | "le" | |
1011 | #endif | |
1012 | ); | |
1013 | if (ret) | |
1014 | goto end; | |
1015 | ||
1016 | ret = _ltt_stream_packet_context_declare(session); | |
1017 | if (ret) | |
1018 | goto end; | |
1019 | ||
1020 | ret = _ltt_event_header_declare(session); | |
1021 | if (ret) | |
1022 | goto end; | |
1023 | ||
1024 | skip_session: | |
b5234c06 | 1025 | cds_list_for_each_entry(chan, &session->chan, list) { |
8020ceb5 MD |
1026 | ret = _ltt_channel_metadata_statedump(session, chan); |
1027 | if (ret) | |
1028 | goto end; | |
1029 | } | |
1030 | ||
b5234c06 | 1031 | cds_list_for_each_entry(event, &session->events, list) { |
8020ceb5 MD |
1032 | ret = _ltt_event_metadata_statedump(session, event->chan, event); |
1033 | if (ret) | |
1034 | goto end; | |
1035 | } | |
1036 | session->metadata_dumped = 1; | |
1037 | end: | |
1038 | return ret; | |
1039 | } | |
1040 | ||
003fedf4 | 1041 | void lttng_ust_events_exit(void) |
8020ceb5 MD |
1042 | { |
1043 | struct ltt_session *session, *tmpsession; | |
1044 | ||
b5234c06 | 1045 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, list) |
8020ceb5 | 1046 | ltt_session_destroy(session); |
8020ceb5 | 1047 | } |