Commit | Line | Data |
---|---|---|
8020ceb5 | 1 | /* |
7dd08bec | 2 | * lttng-events.c |
8020ceb5 | 3 | * |
8020ceb5 MD |
4 | * Holds LTTng per-session event registry. |
5 | * | |
e92f3e28 MD |
6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
8020ceb5 MD |
21 | */ |
22 | ||
b5234c06 MD |
23 | #define _GNU_SOURCE |
24 | #include <stdio.h> | |
25 | #include <urcu/list.h> | |
8165c8da | 26 | #include <urcu/hlist.h> |
b5234c06 | 27 | #include <pthread.h> |
b5234c06 | 28 | #include <errno.h> |
f4681817 MD |
29 | #include <sys/shm.h> |
30 | #include <sys/ipc.h> | |
44c72f10 MD |
31 | #include <stdint.h> |
32 | #include <stddef.h> | |
28b12049 MD |
33 | #include <inttypes.h> |
34 | #include <time.h> | |
2ae57758 | 35 | #include <lttng/ust-endian.h> |
28b12049 | 36 | #include "clock.h" |
44c72f10 MD |
37 | |
38 | #include <urcu-bp.h> | |
39 | #include <urcu/compiler.h> | |
40 | #include <urcu/uatomic.h> | |
41 | #include <urcu/arch.h> | |
42 | ||
43 | #include <lttng/tracepoint.h> | |
4318ae1b | 44 | #include <lttng/ust-events.h> |
44c72f10 MD |
45 | |
46 | #include <usterr-signal-safe.h> | |
47 | #include <helper.h> | |
32ce8569 MD |
48 | #include <ust-ctl.h> |
49 | #include <ust-comm.h> | |
1f18504e | 50 | #include "error.h" |
08114193 | 51 | #include "compat.h" |
eda498b8 | 52 | #include "lttng-ust-uuid.h" |
44c72f10 | 53 | |
457a6b58 | 54 | #include "tracepoint-internal.h" |
7dd08bec MD |
55 | #include "lttng-tracer.h" |
56 | #include "lttng-tracer-core.h" | |
b728d87e | 57 | #include "wait.h" |
8d8a24c8 | 58 | #include "../libringbuffer/shm.h" |
596c4223 | 59 | #include "jhash.h" |
8165c8da MD |
60 | |
61 | /* | |
62 | * The sessions mutex is the centralized mutex across UST tracing | |
17dfb34b MD |
63 | * control and probe registration. All operations within this file are |
64 | * called by the communication thread, under ust_lock protection. | |
8165c8da | 65 | */ |
2b2d6ff7 | 66 | static pthread_mutex_t sessions_mutex = PTHREAD_MUTEX_INITIALIZER; |
8165c8da | 67 | |
17dfb34b | 68 | void ust_lock(void) |
8165c8da MD |
69 | { |
70 | pthread_mutex_lock(&sessions_mutex); | |
71 | } | |
72 | ||
17dfb34b | 73 | void ust_unlock(void) |
8165c8da MD |
74 | { |
75 | pthread_mutex_unlock(&sessions_mutex); | |
76 | } | |
77 | ||
b5234c06 | 78 | static CDS_LIST_HEAD(sessions); |
8165c8da | 79 | |
7dd08bec | 80 | static void _lttng_event_destroy(struct lttng_event *event); |
7dd08bec | 81 | static int _lttng_event_unregister(struct lttng_event *event); |
8020ceb5 | 82 | |
e58095ef MD |
83 | static |
84 | void lttng_session_lazy_sync_enablers(struct lttng_session *session); | |
85 | static | |
86 | void lttng_session_sync_enablers(struct lttng_session *session); | |
87 | static | |
88 | void lttng_enabler_destroy(struct lttng_enabler *enabler); | |
89 | ||
6715d7d1 MD |
90 | /* |
91 | * Called with ust lock held. | |
92 | */ | |
93 | int lttng_session_active(void) | |
94 | { | |
95 | struct lttng_session *iter; | |
96 | ||
97 | cds_list_for_each_entry(iter, &sessions, node) { | |
98 | if (iter->active) | |
99 | return 1; | |
100 | } | |
101 | return 0; | |
102 | } | |
103 | ||
e58095ef MD |
104 | static |
105 | int lttng_loglevel_match(int loglevel, | |
106 | unsigned int has_loglevel, | |
457a6b58 MD |
107 | enum lttng_ust_loglevel_type req_type, |
108 | int req_loglevel) | |
109 | { | |
457a6b58 MD |
110 | if (req_type == LTTNG_UST_LOGLEVEL_ALL) |
111 | return 1; | |
e58095ef MD |
112 | if (!has_loglevel) |
113 | loglevel = TRACE_DEFAULT; | |
457a6b58 MD |
114 | switch (req_type) { |
115 | case LTTNG_UST_LOGLEVEL_RANGE: | |
e58095ef | 116 | if (loglevel <= req_loglevel || req_loglevel == -1) |
457a6b58 MD |
117 | return 1; |
118 | else | |
119 | return 0; | |
120 | case LTTNG_UST_LOGLEVEL_SINGLE: | |
e58095ef | 121 | if (loglevel == req_loglevel || req_loglevel == -1) |
457a6b58 MD |
122 | return 1; |
123 | else | |
124 | return 0; | |
125 | case LTTNG_UST_LOGLEVEL_ALL: | |
126 | default: | |
127 | return 1; | |
128 | } | |
129 | } | |
130 | ||
8020ceb5 MD |
131 | void synchronize_trace(void) |
132 | { | |
8020ceb5 | 133 | synchronize_rcu(); |
8020ceb5 MD |
134 | } |
135 | ||
7dd08bec | 136 | struct lttng_session *lttng_session_create(void) |
8020ceb5 | 137 | { |
7dd08bec | 138 | struct lttng_session *session; |
74d81a6c | 139 | int i; |
8020ceb5 | 140 | |
7dd08bec | 141 | session = zmalloc(sizeof(struct lttng_session)); |
8020ceb5 MD |
142 | if (!session) |
143 | return NULL; | |
e58095ef MD |
144 | CDS_INIT_LIST_HEAD(&session->chan_head); |
145 | CDS_INIT_LIST_HEAD(&session->events_head); | |
146 | CDS_INIT_LIST_HEAD(&session->enablers_head); | |
d56fa719 MD |
147 | for (i = 0; i < LTTNG_UST_EVENT_HT_SIZE; i++) |
148 | CDS_INIT_HLIST_HEAD(&session->events_ht.table[i]); | |
e58095ef | 149 | cds_list_add(&session->node, &sessions); |
8020ceb5 MD |
150 | return session; |
151 | } | |
152 | ||
74d81a6c MD |
153 | /* |
154 | * Only used internally at session destruction. | |
155 | */ | |
156 | static | |
157 | void _lttng_channel_unmap(struct lttng_channel *lttng_chan) | |
158 | { | |
159 | struct channel *chan; | |
160 | struct lttng_ust_shm_handle *handle; | |
161 | ||
162 | cds_list_del(<tng_chan->node); | |
163 | lttng_destroy_context(lttng_chan->ctx); | |
164 | chan = lttng_chan->chan; | |
165 | handle = lttng_chan->handle; | |
166 | /* | |
167 | * note: lttng_chan is private data contained within handle. It | |
168 | * will be freed along with the handle. | |
169 | */ | |
170 | channel_destroy(chan, handle, 0); | |
171 | } | |
172 | ||
7dd08bec | 173 | void lttng_session_destroy(struct lttng_session *session) |
8020ceb5 | 174 | { |
7dd08bec MD |
175 | struct lttng_channel *chan, *tmpchan; |
176 | struct lttng_event *event, *tmpevent; | |
e58095ef | 177 | struct lttng_enabler *enabler, *tmpenabler; |
8020ceb5 MD |
178 | int ret; |
179 | ||
b5234c06 | 180 | CMM_ACCESS_ONCE(session->active) = 0; |
e58095ef | 181 | cds_list_for_each_entry(event, &session->events_head, node) { |
7dd08bec | 182 | ret = _lttng_event_unregister(event); |
8020ceb5 MD |
183 | WARN_ON(ret); |
184 | } | |
185 | synchronize_trace(); /* Wait for in-flight events to complete */ | |
e58095ef MD |
186 | cds_list_for_each_entry_safe(enabler, tmpenabler, |
187 | &session->enablers_head, node) | |
188 | lttng_enabler_destroy(enabler); | |
189 | cds_list_for_each_entry_safe(event, tmpevent, | |
190 | &session->events_head, node) | |
7dd08bec | 191 | _lttng_event_destroy(event); |
e58095ef | 192 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan_head, node) |
74d81a6c | 193 | _lttng_channel_unmap(chan); |
e58095ef | 194 | cds_list_del(&session->node); |
b5234c06 | 195 | free(session); |
8020ceb5 MD |
196 | } |
197 | ||
7dd08bec | 198 | int lttng_session_enable(struct lttng_session *session) |
8020ceb5 MD |
199 | { |
200 | int ret = 0; | |
7dd08bec | 201 | struct lttng_channel *chan; |
32ce8569 | 202 | int notify_socket; |
8020ceb5 | 203 | |
8020ceb5 MD |
204 | if (session->active) { |
205 | ret = -EBUSY; | |
206 | goto end; | |
207 | } | |
208 | ||
32ce8569 MD |
209 | notify_socket = lttng_get_notify_socket(session->owner); |
210 | if (notify_socket < 0) | |
211 | return notify_socket; | |
212 | ||
e58095ef MD |
213 | /* We need to sync enablers with session before activation. */ |
214 | lttng_session_sync_enablers(session); | |
215 | ||
8020ceb5 MD |
216 | /* |
217 | * Snapshot the number of events per channel to know the type of header | |
218 | * we need to use. | |
219 | */ | |
e58095ef | 220 | cds_list_for_each_entry(chan, &session->chan_head, node) { |
32ce8569 MD |
221 | const struct lttng_ctx *ctx; |
222 | const struct lttng_event_field *fields = NULL; | |
223 | size_t nr_fields = 0; | |
224 | ||
225 | /* don't change it if session stop/restart */ | |
8020ceb5 | 226 | if (chan->header_type) |
32ce8569 MD |
227 | continue; |
228 | ctx = chan->ctx; | |
229 | if (ctx) { | |
230 | nr_fields = ctx->nr_fields; | |
231 | fields = &ctx->fields->event_field; | |
232 | } | |
233 | ret = ustcomm_register_channel(notify_socket, | |
234 | session->objd, | |
235 | chan->objd, | |
236 | nr_fields, | |
237 | fields, | |
238 | &chan->id, | |
239 | &chan->header_type); | |
240 | if (ret) | |
241 | return ret; | |
8020ceb5 MD |
242 | } |
243 | ||
b5234c06 MD |
244 | CMM_ACCESS_ONCE(session->active) = 1; |
245 | CMM_ACCESS_ONCE(session->been_active) = 1; | |
8020ceb5 | 246 | end: |
8020ceb5 MD |
247 | return ret; |
248 | } | |
249 | ||
7dd08bec | 250 | int lttng_session_disable(struct lttng_session *session) |
8020ceb5 MD |
251 | { |
252 | int ret = 0; | |
253 | ||
8020ceb5 MD |
254 | if (!session->active) { |
255 | ret = -EBUSY; | |
256 | goto end; | |
257 | } | |
b5234c06 | 258 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 259 | end: |
8020ceb5 MD |
260 | return ret; |
261 | } | |
262 | ||
7dd08bec | 263 | int lttng_channel_enable(struct lttng_channel *channel) |
976fe9ea MD |
264 | { |
265 | int old; | |
266 | ||
9beb36ba MD |
267 | if (channel == channel->session->metadata) |
268 | return -EPERM; | |
b5234c06 | 269 | old = uatomic_xchg(&channel->enabled, 1); |
976fe9ea MD |
270 | if (old) |
271 | return -EEXIST; | |
272 | return 0; | |
273 | } | |
274 | ||
7dd08bec | 275 | int lttng_channel_disable(struct lttng_channel *channel) |
976fe9ea MD |
276 | { |
277 | int old; | |
278 | ||
9beb36ba MD |
279 | if (channel == channel->session->metadata) |
280 | return -EPERM; | |
b5234c06 | 281 | old = uatomic_xchg(&channel->enabled, 0); |
976fe9ea MD |
282 | if (!old) |
283 | return -EEXIST; | |
284 | return 0; | |
285 | } | |
286 | ||
7dd08bec | 287 | int lttng_event_enable(struct lttng_event *event) |
976fe9ea MD |
288 | { |
289 | int old; | |
290 | ||
9beb36ba MD |
291 | if (event->chan == event->chan->session->metadata) |
292 | return -EPERM; | |
b5234c06 | 293 | old = uatomic_xchg(&event->enabled, 1); |
976fe9ea MD |
294 | if (old) |
295 | return -EEXIST; | |
296 | return 0; | |
297 | } | |
298 | ||
7dd08bec | 299 | int lttng_event_disable(struct lttng_event *event) |
976fe9ea MD |
300 | { |
301 | int old; | |
302 | ||
9beb36ba MD |
303 | if (event->chan == event->chan->session->metadata) |
304 | return -EPERM; | |
b5234c06 | 305 | old = uatomic_xchg(&event->enabled, 0); |
976fe9ea MD |
306 | if (!old) |
307 | return -EEXIST; | |
308 | return 0; | |
309 | } | |
310 | ||
8020ceb5 MD |
311 | /* |
312 | * Supports event creation while tracing session is active. | |
313 | */ | |
e58095ef MD |
314 | static |
315 | int lttng_event_create(const struct lttng_event_desc *desc, | |
316 | struct lttng_channel *chan) | |
8020ceb5 | 317 | { |
e58095ef | 318 | const char *event_name = desc->name; |
7dd08bec | 319 | struct lttng_event *event; |
32ce8569 | 320 | struct lttng_session *session = chan->session; |
d56fa719 MD |
321 | struct cds_hlist_head *head; |
322 | struct cds_hlist_node *node; | |
576599a0 | 323 | int ret = 0; |
d56fa719 MD |
324 | size_t name_len = strlen(event_name); |
325 | uint32_t hash; | |
32ce8569 MD |
326 | int notify_socket, loglevel; |
327 | const char *uri; | |
8020ceb5 | 328 | |
d56fa719 MD |
329 | hash = jhash(event_name, name_len, 0); |
330 | head = &chan->session->events_ht.table[hash & (LTTNG_UST_EVENT_HT_SIZE - 1)]; | |
331 | cds_hlist_for_each_entry(event, node, head, hlist) { | |
e58095ef MD |
332 | assert(event->desc); |
333 | if (!strncmp(event->desc->name, | |
334 | desc->name, | |
ff412fb5 | 335 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
576599a0 | 336 | ret = -EEXIST; |
8020ceb5 | 337 | goto exist; |
576599a0 MD |
338 | } |
339 | } | |
457a6b58 | 340 | |
32ce8569 MD |
341 | notify_socket = lttng_get_notify_socket(session->owner); |
342 | if (notify_socket < 0) { | |
343 | ret = notify_socket; | |
344 | goto socket_error; | |
345 | } | |
346 | ||
457a6b58 MD |
347 | /* |
348 | * Check if loglevel match. Refuse to connect event if not. | |
349 | */ | |
7dd08bec | 350 | event = zmalloc(sizeof(struct lttng_event)); |
576599a0 MD |
351 | if (!event) { |
352 | ret = -ENOMEM; | |
8020ceb5 | 353 | goto cache_error; |
576599a0 | 354 | } |
8020ceb5 | 355 | event->chan = chan; |
e58095ef | 356 | |
976fe9ea | 357 | event->enabled = 1; |
e58095ef MD |
358 | CDS_INIT_LIST_HEAD(&event->bytecode_runtime_head); |
359 | CDS_INIT_LIST_HEAD(&event->enablers_ref_head); | |
360 | event->desc = desc; | |
32ce8569 MD |
361 | |
362 | if (desc->loglevel) | |
363 | loglevel = *(*event->desc->loglevel); | |
364 | else | |
365 | loglevel = TRACE_DEFAULT; | |
366 | if (desc->u.ext.model_emf_uri) | |
367 | uri = *(desc->u.ext.model_emf_uri); | |
368 | else | |
369 | uri = NULL; | |
370 | ||
2b213b16 MD |
371 | /* Don't register metadata events */ |
372 | if (session->metadata == chan) { | |
373 | event->id = -1U; | |
374 | } else { | |
375 | /* Fetch event ID from sessiond */ | |
376 | ret = ustcomm_register_event(notify_socket, | |
377 | session->objd, | |
378 | chan->objd, | |
379 | event_name, | |
380 | loglevel, | |
381 | desc->signature, | |
382 | desc->nr_fields, | |
383 | desc->fields, | |
384 | uri, | |
385 | &event->id); | |
386 | if (ret < 0) { | |
387 | goto sessiond_register_error; | |
388 | } | |
32ce8569 | 389 | } |
2b213b16 | 390 | |
7dd08bec | 391 | /* Populate lttng_event structure before tracepoint registration. */ |
b5234c06 | 392 | cmm_smp_wmb(); |
e58095ef MD |
393 | ret = __tracepoint_probe_register(event_name, |
394 | desc->probe_callback, | |
395 | event, desc->signature); | |
396 | if (ret) | |
32ce8569 MD |
397 | goto tracepoint_register_error; |
398 | ||
e58095ef | 399 | cds_list_add(&event->node, &chan->session->events_head); |
d56fa719 | 400 | cds_hlist_add_head(&event->hlist, head); |
576599a0 | 401 | return 0; |
8020ceb5 | 402 | |
32ce8569 MD |
403 | tracepoint_register_error: |
404 | sessiond_register_error: | |
b5234c06 | 405 | free(event); |
8020ceb5 | 406 | cache_error: |
32ce8569 | 407 | socket_error: |
8020ceb5 | 408 | exist: |
576599a0 | 409 | return ret; |
8020ceb5 MD |
410 | } |
411 | ||
e58095ef MD |
412 | static |
413 | int lttng_desc_match_wildcard_enabler(const struct lttng_event_desc *desc, | |
414 | struct lttng_enabler *enabler) | |
415 | { | |
416 | int loglevel = 0; | |
417 | unsigned int has_loglevel; | |
418 | ||
419 | assert(enabler->type == LTTNG_ENABLER_WILDCARD); | |
420 | /* Compare excluding final '*' */ | |
421 | if (strncmp(desc->name, enabler->event_param.name, | |
422 | strlen(enabler->event_param.name) - 1)) | |
423 | return 0; | |
424 | if (desc->loglevel) { | |
425 | loglevel = *(*desc->loglevel); | |
426 | has_loglevel = 1; | |
427 | } | |
428 | if (!lttng_loglevel_match(loglevel, | |
429 | has_loglevel, | |
430 | enabler->event_param.loglevel_type, | |
431 | enabler->event_param.loglevel)) | |
432 | return 0; | |
433 | return 1; | |
434 | } | |
435 | ||
436 | static | |
437 | int lttng_desc_match_event_enabler(const struct lttng_event_desc *desc, | |
438 | struct lttng_enabler *enabler) | |
439 | { | |
440 | int loglevel = 0; | |
441 | unsigned int has_loglevel = 0; | |
442 | ||
443 | assert(enabler->type == LTTNG_ENABLER_EVENT); | |
444 | if (strcmp(desc->name, enabler->event_param.name)) | |
445 | return 0; | |
446 | if (desc->loglevel) { | |
447 | loglevel = *(*desc->loglevel); | |
448 | has_loglevel = 1; | |
449 | } | |
450 | if (!lttng_loglevel_match(loglevel, | |
451 | has_loglevel, | |
452 | enabler->event_param.loglevel_type, | |
453 | enabler->event_param.loglevel)) | |
454 | return 0; | |
455 | return 1; | |
456 | } | |
457 | ||
458 | static | |
459 | int lttng_desc_match_enabler(const struct lttng_event_desc *desc, | |
460 | struct lttng_enabler *enabler) | |
461 | { | |
462 | switch (enabler->type) { | |
463 | case LTTNG_ENABLER_WILDCARD: | |
464 | return lttng_desc_match_wildcard_enabler(desc, enabler); | |
465 | case LTTNG_ENABLER_EVENT: | |
466 | return lttng_desc_match_event_enabler(desc, enabler); | |
467 | default: | |
468 | return -EINVAL; | |
469 | } | |
470 | } | |
471 | ||
472 | static | |
473 | int lttng_event_match_enabler(struct lttng_event *event, | |
474 | struct lttng_enabler *enabler) | |
475 | { | |
476 | return lttng_desc_match_enabler(event->desc, enabler); | |
477 | } | |
478 | ||
479 | static | |
480 | struct lttng_enabler_ref * lttng_event_enabler_ref(struct lttng_event *event, | |
481 | struct lttng_enabler *enabler) | |
482 | { | |
483 | struct lttng_enabler_ref *enabler_ref; | |
484 | ||
485 | cds_list_for_each_entry(enabler_ref, | |
486 | &event->enablers_ref_head, node) { | |
487 | if (enabler_ref->ref == enabler) | |
488 | return enabler_ref; | |
489 | } | |
490 | return NULL; | |
491 | } | |
492 | ||
8020ceb5 | 493 | /* |
e58095ef MD |
494 | * Create struct lttng_event if it is missing and present in the list of |
495 | * tracepoint probes. | |
8020ceb5 | 496 | */ |
e58095ef MD |
497 | static |
498 | void lttng_create_event_if_missing(struct lttng_enabler *enabler) | |
8020ceb5 | 499 | { |
e58095ef MD |
500 | struct lttng_session *session = enabler->chan->session; |
501 | struct lttng_probe_desc *probe_desc; | |
502 | const struct lttng_event_desc *desc; | |
503 | struct lttng_event *event; | |
504 | int i; | |
505 | struct cds_list_head *probe_list; | |
506 | ||
507 | probe_list = lttng_get_probe_list_head(); | |
508 | /* | |
509 | * For each probe event, if we find that a probe event matches | |
510 | * our enabler, create an associated lttng_event if not | |
511 | * already present. | |
512 | */ | |
513 | cds_list_for_each_entry(probe_desc, probe_list, head) { | |
514 | for (i = 0; i < probe_desc->nr_events; i++) { | |
515 | int found = 0, ret; | |
d56fa719 MD |
516 | struct cds_hlist_head *head; |
517 | struct cds_hlist_node *node; | |
518 | const char *event_name; | |
519 | size_t name_len; | |
520 | uint32_t hash; | |
e58095ef MD |
521 | |
522 | desc = probe_desc->event_desc[i]; | |
523 | if (!lttng_desc_match_enabler(desc, enabler)) | |
524 | continue; | |
d56fa719 MD |
525 | event_name = desc->name; |
526 | name_len = strlen(event_name); | |
e58095ef MD |
527 | |
528 | /* | |
d56fa719 | 529 | * Check if already created. |
e58095ef | 530 | */ |
d56fa719 MD |
531 | hash = jhash(event_name, name_len, 0); |
532 | head = &session->events_ht.table[hash & (LTTNG_UST_EVENT_HT_SIZE - 1)]; | |
533 | cds_hlist_for_each_entry(event, node, head, hlist) { | |
e58095ef MD |
534 | if (event->desc == desc) |
535 | found = 1; | |
536 | } | |
537 | if (found) | |
538 | continue; | |
539 | ||
540 | /* | |
541 | * We need to create an event for this | |
542 | * event probe. | |
543 | */ | |
544 | ret = lttng_event_create(probe_desc->event_desc[i], | |
545 | enabler->chan); | |
546 | if (ret) { | |
32ce8569 MD |
547 | DBG("Unable to create event %s, error %d\n", |
548 | probe_desc->event_desc[i]->name, ret); | |
e58095ef | 549 | } |
8165c8da | 550 | } |
8020ceb5 | 551 | } |
8020ceb5 MD |
552 | } |
553 | ||
554 | /* | |
e58095ef MD |
555 | * Create events associated with an enabler (if not already present), |
556 | * and add backward reference from the event to the enabler. | |
8020ceb5 MD |
557 | */ |
558 | static | |
e58095ef | 559 | int lttng_enabler_ref_events(struct lttng_enabler *enabler) |
8020ceb5 | 560 | { |
e58095ef MD |
561 | struct lttng_session *session = enabler->chan->session; |
562 | struct lttng_event *event; | |
563 | ||
564 | /* First ensure that probe events are created for this enabler. */ | |
565 | lttng_create_event_if_missing(enabler); | |
566 | ||
567 | /* For each event matching enabler in session event list. */ | |
568 | cds_list_for_each_entry(event, &session->events_head, node) { | |
569 | struct lttng_enabler_ref *enabler_ref; | |
570 | ||
571 | if (!lttng_event_match_enabler(event, enabler)) | |
572 | continue; | |
573 | ||
574 | enabler_ref = lttng_event_enabler_ref(event, enabler); | |
575 | if (!enabler_ref) { | |
576 | /* | |
577 | * If no backward ref, create it. | |
578 | * Add backward ref from event to enabler. | |
579 | */ | |
580 | enabler_ref = zmalloc(sizeof(*enabler_ref)); | |
581 | if (!enabler_ref) | |
582 | return -ENOMEM; | |
583 | enabler_ref->ref = enabler; | |
584 | cds_list_add(&enabler_ref->node, | |
585 | &event->enablers_ref_head); | |
8165c8da | 586 | } |
e58095ef MD |
587 | |
588 | /* | |
589 | * Link filter bytecodes if not linked yet. | |
590 | */ | |
591 | lttng_enabler_event_link_bytecode(event, enabler); | |
592 | ||
593 | /* TODO: merge event context. */ | |
594 | } | |
595 | return 0; | |
596 | } | |
597 | ||
598 | /* | |
599 | * Called at library load: connect the probe on all enablers matching | |
600 | * this event. | |
601 | * called with session mutex held. | |
602 | * TODO: currently, for each desc added, we iterate on all event desc | |
603 | * (inefficient). We should create specific code that only target the | |
604 | * added desc. | |
605 | */ | |
606 | int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc) | |
607 | { | |
608 | struct lttng_session *session; | |
609 | ||
610 | cds_list_for_each_entry(session, &sessions, node) { | |
611 | lttng_session_lazy_sync_enablers(session); | |
8020ceb5 | 612 | } |
e58095ef MD |
613 | return 0; |
614 | } | |
615 | ||
616 | /* | |
617 | * Only used internally at session destruction. | |
618 | */ | |
619 | int _lttng_event_unregister(struct lttng_event *event) | |
620 | { | |
621 | return __tracepoint_probe_unregister(event->desc->name, | |
622 | event->desc->probe_callback, | |
623 | event); | |
624 | } | |
625 | ||
626 | /* | |
627 | * Only used internally at session destruction. | |
628 | */ | |
629 | static | |
630 | void _lttng_event_destroy(struct lttng_event *event) | |
631 | { | |
632 | struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref; | |
633 | ||
e58095ef | 634 | cds_list_del(&event->node); |
8020ceb5 | 635 | lttng_destroy_context(event->ctx); |
f488575f | 636 | lttng_free_event_filter_runtime(event); |
e58095ef MD |
637 | /* Free event enabler refs */ |
638 | cds_list_for_each_entry_safe(enabler_ref, tmp_enabler_ref, | |
639 | &event->enablers_ref_head, node) | |
640 | free(enabler_ref); | |
b5234c06 | 641 | free(event); |
8020ceb5 MD |
642 | } |
643 | ||
003fedf4 | 644 | void lttng_ust_events_exit(void) |
8020ceb5 | 645 | { |
7dd08bec | 646 | struct lttng_session *session, *tmpsession; |
8020ceb5 | 647 | |
e58095ef | 648 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, node) |
7dd08bec | 649 | lttng_session_destroy(session); |
8020ceb5 | 650 | } |
457a6b58 | 651 | |
e58095ef MD |
652 | /* |
653 | * Enabler management. | |
654 | */ | |
655 | struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, | |
656 | struct lttng_ust_event *event_param, | |
657 | struct lttng_channel *chan) | |
457a6b58 | 658 | { |
e58095ef MD |
659 | struct lttng_enabler *enabler; |
660 | ||
661 | enabler = zmalloc(sizeof(*enabler)); | |
662 | if (!enabler) | |
663 | return NULL; | |
664 | enabler->type = type; | |
665 | CDS_INIT_LIST_HEAD(&enabler->filter_bytecode_head); | |
666 | memcpy(&enabler->event_param, event_param, | |
667 | sizeof(enabler->event_param)); | |
668 | enabler->chan = chan; | |
669 | /* ctx left NULL */ | |
670 | enabler->enabled = 1; | |
671 | cds_list_add(&enabler->node, &enabler->chan->session->enablers_head); | |
672 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
673 | return enabler; | |
457a6b58 MD |
674 | } |
675 | ||
e58095ef | 676 | int lttng_enabler_enable(struct lttng_enabler *enabler) |
457a6b58 | 677 | { |
e58095ef MD |
678 | enabler->enabled = 1; |
679 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
680 | return 0; | |
457a6b58 | 681 | } |
457a6b58 | 682 | |
e58095ef | 683 | int lttng_enabler_disable(struct lttng_enabler *enabler) |
457a6b58 | 684 | { |
e58095ef MD |
685 | if (enabler->chan == enabler->chan->session->metadata) |
686 | return -EPERM; | |
687 | enabler->enabled = 0; | |
688 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
689 | return 0; | |
690 | } | |
457a6b58 | 691 | |
e58095ef MD |
692 | int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler, |
693 | struct lttng_ust_filter_bytecode_node *bytecode) | |
694 | { | |
695 | bytecode->enabler = enabler; | |
696 | cds_list_add_tail(&bytecode->node, &enabler->filter_bytecode_head); | |
697 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
698 | return 0; | |
699 | } | |
f488575f | 700 | |
e58095ef MD |
701 | int lttng_attach_context(struct lttng_ust_context *context_param, |
702 | struct lttng_ctx **ctx, struct lttng_session *session) | |
703 | { | |
457a6b58 | 704 | /* |
e58095ef MD |
705 | * We cannot attach a context after trace has been started for a |
706 | * session because the metadata does not allow expressing this | |
707 | * information outside of the original channel scope. | |
457a6b58 | 708 | */ |
e58095ef MD |
709 | if (session->been_active) |
710 | return -EPERM; | |
457a6b58 | 711 | |
e58095ef MD |
712 | switch (context_param->ctx) { |
713 | case LTTNG_UST_CONTEXT_PTHREAD_ID: | |
714 | return lttng_add_pthread_id_to_ctx(ctx); | |
715 | case LTTNG_UST_CONTEXT_VTID: | |
716 | return lttng_add_vtid_to_ctx(ctx); | |
717 | case LTTNG_UST_CONTEXT_VPID: | |
718 | return lttng_add_vpid_to_ctx(ctx); | |
719 | case LTTNG_UST_CONTEXT_PROCNAME: | |
720 | return lttng_add_procname_to_ctx(ctx); | |
721 | default: | |
722 | return -EINVAL; | |
457a6b58 | 723 | } |
457a6b58 MD |
724 | } |
725 | ||
e58095ef MD |
726 | int lttng_enabler_attach_context(struct lttng_enabler *enabler, |
727 | struct lttng_ust_context *context_param) | |
457a6b58 | 728 | { |
e58095ef MD |
729 | #if 0 // disabled for now. |
730 | struct lttng_session *session = enabler->chan->session; | |
731 | int ret; | |
457a6b58 | 732 | |
e58095ef MD |
733 | ret = lttng_attach_context(context_param, &enabler->ctx, |
734 | session); | |
735 | if (ret) | |
736 | return ret; | |
737 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
738 | #endif | |
739 | return -ENOSYS; | |
457a6b58 MD |
740 | } |
741 | ||
e58095ef MD |
742 | static |
743 | void lttng_enabler_destroy(struct lttng_enabler *enabler) | |
457a6b58 | 744 | { |
e58095ef | 745 | struct lttng_ust_filter_bytecode_node *filter_node, *tmp_filter_node; |
457a6b58 | 746 | |
e58095ef MD |
747 | /* Destroy filter bytecode */ |
748 | cds_list_for_each_entry_safe(filter_node, tmp_filter_node, | |
749 | &enabler->filter_bytecode_head, node) { | |
750 | free(filter_node); | |
457a6b58 | 751 | } |
e58095ef MD |
752 | |
753 | /* Destroy contexts */ | |
754 | lttng_destroy_context(enabler->ctx); | |
755 | ||
756 | cds_list_del(&enabler->node); | |
757 | free(enabler); | |
457a6b58 MD |
758 | } |
759 | ||
e58095ef MD |
760 | /* |
761 | * lttng_session_sync_enablers should be called just before starting a | |
762 | * session. | |
763 | */ | |
457a6b58 | 764 | static |
e58095ef | 765 | void lttng_session_sync_enablers(struct lttng_session *session) |
457a6b58 | 766 | { |
e58095ef MD |
767 | struct lttng_enabler *enabler; |
768 | struct lttng_event *event; | |
457a6b58 | 769 | |
e58095ef MD |
770 | cds_list_for_each_entry(enabler, &session->enablers_head, node) |
771 | lttng_enabler_ref_events(enabler); | |
772 | /* | |
773 | * For each event, if at least one of its enablers is enabled, | |
774 | * we enable the event, else we disable it. | |
775 | */ | |
776 | cds_list_for_each_entry(event, &session->events_head, node) { | |
777 | struct lttng_enabler_ref *enabler_ref; | |
778 | struct lttng_bytecode_runtime *runtime; | |
dcdeaff0 | 779 | int enabled = 0, has_enablers_without_bytecode = 0; |
e58095ef MD |
780 | |
781 | /* Enable events */ | |
782 | cds_list_for_each_entry(enabler_ref, | |
783 | &event->enablers_ref_head, node) { | |
784 | if (enabler_ref->ref->enabled) { | |
785 | enabled = 1; | |
786 | break; | |
787 | } | |
788 | } | |
789 | event->enabled = enabled; | |
457a6b58 | 790 | |
1f49fc05 | 791 | /* Check if has enablers without bytecode enabled */ |
dcdeaff0 MD |
792 | cds_list_for_each_entry(enabler_ref, |
793 | &event->enablers_ref_head, node) { | |
1f49fc05 MD |
794 | if (enabler_ref->ref->enabled |
795 | && cds_list_empty(&enabler_ref->ref->filter_bytecode_head)) { | |
dcdeaff0 MD |
796 | has_enablers_without_bytecode = 1; |
797 | break; | |
798 | } | |
799 | } | |
800 | event->has_enablers_without_bytecode = | |
801 | has_enablers_without_bytecode; | |
802 | ||
e58095ef MD |
803 | /* Enable filters */ |
804 | cds_list_for_each_entry(runtime, | |
805 | &event->bytecode_runtime_head, node) { | |
806 | lttng_filter_sync_state(runtime); | |
457a6b58 MD |
807 | } |
808 | } | |
457a6b58 MD |
809 | } |
810 | ||
e58095ef MD |
811 | /* |
812 | * Apply enablers to session events, adding events to session if need | |
813 | * be. It is required after each modification applied to an active | |
814 | * session, and right before session "start". | |
815 | * "lazy" sync means we only sync if required. | |
816 | */ | |
817 | static | |
818 | void lttng_session_lazy_sync_enablers(struct lttng_session *session) | |
457a6b58 | 819 | { |
e58095ef MD |
820 | /* We can skip if session is not active */ |
821 | if (!session->active) | |
822 | return; | |
823 | lttng_session_sync_enablers(session); | |
457a6b58 | 824 | } |