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