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); | |
b869b5ae MD |
240 | if (ret) { |
241 | DBG("Error (%d) registering channel to sessiond", ret); | |
32ce8569 | 242 | return ret; |
b869b5ae | 243 | } |
8020ceb5 MD |
244 | } |
245 | ||
b5234c06 MD |
246 | CMM_ACCESS_ONCE(session->active) = 1; |
247 | CMM_ACCESS_ONCE(session->been_active) = 1; | |
8020ceb5 | 248 | end: |
8020ceb5 MD |
249 | return ret; |
250 | } | |
251 | ||
7dd08bec | 252 | int lttng_session_disable(struct lttng_session *session) |
8020ceb5 MD |
253 | { |
254 | int ret = 0; | |
255 | ||
8020ceb5 MD |
256 | if (!session->active) { |
257 | ret = -EBUSY; | |
258 | goto end; | |
259 | } | |
b5234c06 | 260 | CMM_ACCESS_ONCE(session->active) = 0; |
8020ceb5 | 261 | end: |
8020ceb5 MD |
262 | return ret; |
263 | } | |
264 | ||
7dd08bec | 265 | int lttng_channel_enable(struct lttng_channel *channel) |
976fe9ea MD |
266 | { |
267 | int old; | |
268 | ||
9beb36ba MD |
269 | if (channel == channel->session->metadata) |
270 | return -EPERM; | |
b5234c06 | 271 | old = uatomic_xchg(&channel->enabled, 1); |
976fe9ea MD |
272 | if (old) |
273 | return -EEXIST; | |
274 | return 0; | |
275 | } | |
276 | ||
7dd08bec | 277 | int lttng_channel_disable(struct lttng_channel *channel) |
976fe9ea MD |
278 | { |
279 | int old; | |
280 | ||
9beb36ba MD |
281 | if (channel == channel->session->metadata) |
282 | return -EPERM; | |
b5234c06 | 283 | old = uatomic_xchg(&channel->enabled, 0); |
976fe9ea MD |
284 | if (!old) |
285 | return -EEXIST; | |
286 | return 0; | |
287 | } | |
288 | ||
7dd08bec | 289 | int lttng_event_enable(struct lttng_event *event) |
976fe9ea MD |
290 | { |
291 | int old; | |
292 | ||
9beb36ba MD |
293 | if (event->chan == event->chan->session->metadata) |
294 | return -EPERM; | |
b5234c06 | 295 | old = uatomic_xchg(&event->enabled, 1); |
976fe9ea MD |
296 | if (old) |
297 | return -EEXIST; | |
298 | return 0; | |
299 | } | |
300 | ||
7dd08bec | 301 | int lttng_event_disable(struct lttng_event *event) |
976fe9ea MD |
302 | { |
303 | int old; | |
304 | ||
9beb36ba MD |
305 | if (event->chan == event->chan->session->metadata) |
306 | return -EPERM; | |
b5234c06 | 307 | old = uatomic_xchg(&event->enabled, 0); |
976fe9ea MD |
308 | if (!old) |
309 | return -EEXIST; | |
310 | return 0; | |
311 | } | |
312 | ||
8020ceb5 MD |
313 | /* |
314 | * Supports event creation while tracing session is active. | |
315 | */ | |
e58095ef MD |
316 | static |
317 | int lttng_event_create(const struct lttng_event_desc *desc, | |
318 | struct lttng_channel *chan) | |
8020ceb5 | 319 | { |
e58095ef | 320 | const char *event_name = desc->name; |
7dd08bec | 321 | struct lttng_event *event; |
32ce8569 | 322 | struct lttng_session *session = chan->session; |
d56fa719 MD |
323 | struct cds_hlist_head *head; |
324 | struct cds_hlist_node *node; | |
576599a0 | 325 | int ret = 0; |
d56fa719 MD |
326 | size_t name_len = strlen(event_name); |
327 | uint32_t hash; | |
32ce8569 MD |
328 | int notify_socket, loglevel; |
329 | const char *uri; | |
8020ceb5 | 330 | |
d56fa719 MD |
331 | hash = jhash(event_name, name_len, 0); |
332 | head = &chan->session->events_ht.table[hash & (LTTNG_UST_EVENT_HT_SIZE - 1)]; | |
333 | cds_hlist_for_each_entry(event, node, head, hlist) { | |
e58095ef MD |
334 | assert(event->desc); |
335 | if (!strncmp(event->desc->name, | |
336 | desc->name, | |
ff412fb5 | 337 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
576599a0 | 338 | ret = -EEXIST; |
8020ceb5 | 339 | goto exist; |
576599a0 MD |
340 | } |
341 | } | |
457a6b58 | 342 | |
32ce8569 MD |
343 | notify_socket = lttng_get_notify_socket(session->owner); |
344 | if (notify_socket < 0) { | |
345 | ret = notify_socket; | |
346 | goto socket_error; | |
347 | } | |
348 | ||
457a6b58 MD |
349 | /* |
350 | * Check if loglevel match. Refuse to connect event if not. | |
351 | */ | |
7dd08bec | 352 | event = zmalloc(sizeof(struct lttng_event)); |
576599a0 MD |
353 | if (!event) { |
354 | ret = -ENOMEM; | |
8020ceb5 | 355 | goto cache_error; |
576599a0 | 356 | } |
8020ceb5 | 357 | event->chan = chan; |
e58095ef | 358 | |
976fe9ea | 359 | event->enabled = 1; |
e58095ef MD |
360 | CDS_INIT_LIST_HEAD(&event->bytecode_runtime_head); |
361 | CDS_INIT_LIST_HEAD(&event->enablers_ref_head); | |
362 | event->desc = desc; | |
32ce8569 MD |
363 | |
364 | if (desc->loglevel) | |
365 | loglevel = *(*event->desc->loglevel); | |
366 | else | |
367 | loglevel = TRACE_DEFAULT; | |
368 | if (desc->u.ext.model_emf_uri) | |
369 | uri = *(desc->u.ext.model_emf_uri); | |
370 | else | |
371 | uri = NULL; | |
372 | ||
2b213b16 MD |
373 | /* Don't register metadata events */ |
374 | if (session->metadata == chan) { | |
375 | event->id = -1U; | |
376 | } else { | |
377 | /* Fetch event ID from sessiond */ | |
378 | ret = ustcomm_register_event(notify_socket, | |
379 | session->objd, | |
380 | chan->objd, | |
381 | event_name, | |
382 | loglevel, | |
383 | desc->signature, | |
384 | desc->nr_fields, | |
385 | desc->fields, | |
386 | uri, | |
387 | &event->id); | |
388 | if (ret < 0) { | |
b869b5ae | 389 | DBG("Error (%d) registering event to sessiond", ret); |
2b213b16 MD |
390 | goto sessiond_register_error; |
391 | } | |
32ce8569 | 392 | } |
2b213b16 | 393 | |
7dd08bec | 394 | /* Populate lttng_event structure before tracepoint registration. */ |
b5234c06 | 395 | cmm_smp_wmb(); |
e58095ef MD |
396 | ret = __tracepoint_probe_register(event_name, |
397 | desc->probe_callback, | |
398 | event, desc->signature); | |
399 | if (ret) | |
32ce8569 MD |
400 | goto tracepoint_register_error; |
401 | ||
e58095ef | 402 | cds_list_add(&event->node, &chan->session->events_head); |
d56fa719 | 403 | cds_hlist_add_head(&event->hlist, head); |
576599a0 | 404 | return 0; |
8020ceb5 | 405 | |
32ce8569 MD |
406 | tracepoint_register_error: |
407 | sessiond_register_error: | |
b5234c06 | 408 | free(event); |
8020ceb5 | 409 | cache_error: |
32ce8569 | 410 | socket_error: |
8020ceb5 | 411 | exist: |
576599a0 | 412 | return ret; |
8020ceb5 MD |
413 | } |
414 | ||
e58095ef MD |
415 | static |
416 | int lttng_desc_match_wildcard_enabler(const struct lttng_event_desc *desc, | |
417 | struct lttng_enabler *enabler) | |
418 | { | |
419 | int loglevel = 0; | |
420 | unsigned int has_loglevel; | |
421 | ||
422 | assert(enabler->type == LTTNG_ENABLER_WILDCARD); | |
423 | /* Compare excluding final '*' */ | |
424 | if (strncmp(desc->name, enabler->event_param.name, | |
425 | strlen(enabler->event_param.name) - 1)) | |
426 | return 0; | |
427 | if (desc->loglevel) { | |
428 | loglevel = *(*desc->loglevel); | |
429 | has_loglevel = 1; | |
430 | } | |
431 | if (!lttng_loglevel_match(loglevel, | |
432 | has_loglevel, | |
433 | enabler->event_param.loglevel_type, | |
434 | enabler->event_param.loglevel)) | |
435 | return 0; | |
436 | return 1; | |
437 | } | |
438 | ||
439 | static | |
440 | int lttng_desc_match_event_enabler(const struct lttng_event_desc *desc, | |
441 | struct lttng_enabler *enabler) | |
442 | { | |
443 | int loglevel = 0; | |
444 | unsigned int has_loglevel = 0; | |
445 | ||
446 | assert(enabler->type == LTTNG_ENABLER_EVENT); | |
447 | if (strcmp(desc->name, enabler->event_param.name)) | |
448 | return 0; | |
449 | if (desc->loglevel) { | |
450 | loglevel = *(*desc->loglevel); | |
451 | has_loglevel = 1; | |
452 | } | |
453 | if (!lttng_loglevel_match(loglevel, | |
454 | has_loglevel, | |
455 | enabler->event_param.loglevel_type, | |
456 | enabler->event_param.loglevel)) | |
457 | return 0; | |
458 | return 1; | |
459 | } | |
460 | ||
461 | static | |
462 | int lttng_desc_match_enabler(const struct lttng_event_desc *desc, | |
463 | struct lttng_enabler *enabler) | |
464 | { | |
465 | switch (enabler->type) { | |
466 | case LTTNG_ENABLER_WILDCARD: | |
467 | return lttng_desc_match_wildcard_enabler(desc, enabler); | |
468 | case LTTNG_ENABLER_EVENT: | |
469 | return lttng_desc_match_event_enabler(desc, enabler); | |
470 | default: | |
471 | return -EINVAL; | |
472 | } | |
473 | } | |
474 | ||
475 | static | |
476 | int lttng_event_match_enabler(struct lttng_event *event, | |
477 | struct lttng_enabler *enabler) | |
478 | { | |
479 | return lttng_desc_match_enabler(event->desc, enabler); | |
480 | } | |
481 | ||
482 | static | |
483 | struct lttng_enabler_ref * lttng_event_enabler_ref(struct lttng_event *event, | |
484 | struct lttng_enabler *enabler) | |
485 | { | |
486 | struct lttng_enabler_ref *enabler_ref; | |
487 | ||
488 | cds_list_for_each_entry(enabler_ref, | |
489 | &event->enablers_ref_head, node) { | |
490 | if (enabler_ref->ref == enabler) | |
491 | return enabler_ref; | |
492 | } | |
493 | return NULL; | |
494 | } | |
495 | ||
8020ceb5 | 496 | /* |
e58095ef MD |
497 | * Create struct lttng_event if it is missing and present in the list of |
498 | * tracepoint probes. | |
8020ceb5 | 499 | */ |
e58095ef MD |
500 | static |
501 | void lttng_create_event_if_missing(struct lttng_enabler *enabler) | |
8020ceb5 | 502 | { |
e58095ef MD |
503 | struct lttng_session *session = enabler->chan->session; |
504 | struct lttng_probe_desc *probe_desc; | |
505 | const struct lttng_event_desc *desc; | |
506 | struct lttng_event *event; | |
507 | int i; | |
508 | struct cds_list_head *probe_list; | |
509 | ||
510 | probe_list = lttng_get_probe_list_head(); | |
511 | /* | |
512 | * For each probe event, if we find that a probe event matches | |
513 | * our enabler, create an associated lttng_event if not | |
514 | * already present. | |
515 | */ | |
516 | cds_list_for_each_entry(probe_desc, probe_list, head) { | |
517 | for (i = 0; i < probe_desc->nr_events; i++) { | |
518 | int found = 0, ret; | |
d56fa719 MD |
519 | struct cds_hlist_head *head; |
520 | struct cds_hlist_node *node; | |
521 | const char *event_name; | |
522 | size_t name_len; | |
523 | uint32_t hash; | |
e58095ef MD |
524 | |
525 | desc = probe_desc->event_desc[i]; | |
526 | if (!lttng_desc_match_enabler(desc, enabler)) | |
527 | continue; | |
d56fa719 MD |
528 | event_name = desc->name; |
529 | name_len = strlen(event_name); | |
e58095ef MD |
530 | |
531 | /* | |
d56fa719 | 532 | * Check if already created. |
e58095ef | 533 | */ |
d56fa719 MD |
534 | hash = jhash(event_name, name_len, 0); |
535 | head = &session->events_ht.table[hash & (LTTNG_UST_EVENT_HT_SIZE - 1)]; | |
536 | cds_hlist_for_each_entry(event, node, head, hlist) { | |
e58095ef MD |
537 | if (event->desc == desc) |
538 | found = 1; | |
539 | } | |
540 | if (found) | |
541 | continue; | |
542 | ||
543 | /* | |
544 | * We need to create an event for this | |
545 | * event probe. | |
546 | */ | |
547 | ret = lttng_event_create(probe_desc->event_desc[i], | |
548 | enabler->chan); | |
549 | if (ret) { | |
32ce8569 MD |
550 | DBG("Unable to create event %s, error %d\n", |
551 | probe_desc->event_desc[i]->name, ret); | |
e58095ef | 552 | } |
8165c8da | 553 | } |
8020ceb5 | 554 | } |
8020ceb5 MD |
555 | } |
556 | ||
557 | /* | |
e58095ef MD |
558 | * Create events associated with an enabler (if not already present), |
559 | * and add backward reference from the event to the enabler. | |
8020ceb5 MD |
560 | */ |
561 | static | |
e58095ef | 562 | int lttng_enabler_ref_events(struct lttng_enabler *enabler) |
8020ceb5 | 563 | { |
e58095ef MD |
564 | struct lttng_session *session = enabler->chan->session; |
565 | struct lttng_event *event; | |
566 | ||
567 | /* First ensure that probe events are created for this enabler. */ | |
568 | lttng_create_event_if_missing(enabler); | |
569 | ||
570 | /* For each event matching enabler in session event list. */ | |
571 | cds_list_for_each_entry(event, &session->events_head, node) { | |
572 | struct lttng_enabler_ref *enabler_ref; | |
573 | ||
574 | if (!lttng_event_match_enabler(event, enabler)) | |
575 | continue; | |
576 | ||
577 | enabler_ref = lttng_event_enabler_ref(event, enabler); | |
578 | if (!enabler_ref) { | |
579 | /* | |
580 | * If no backward ref, create it. | |
581 | * Add backward ref from event to enabler. | |
582 | */ | |
583 | enabler_ref = zmalloc(sizeof(*enabler_ref)); | |
584 | if (!enabler_ref) | |
585 | return -ENOMEM; | |
586 | enabler_ref->ref = enabler; | |
587 | cds_list_add(&enabler_ref->node, | |
588 | &event->enablers_ref_head); | |
8165c8da | 589 | } |
e58095ef MD |
590 | |
591 | /* | |
592 | * Link filter bytecodes if not linked yet. | |
593 | */ | |
594 | lttng_enabler_event_link_bytecode(event, enabler); | |
595 | ||
596 | /* TODO: merge event context. */ | |
597 | } | |
598 | return 0; | |
599 | } | |
600 | ||
601 | /* | |
602 | * Called at library load: connect the probe on all enablers matching | |
603 | * this event. | |
604 | * called with session mutex held. | |
605 | * TODO: currently, for each desc added, we iterate on all event desc | |
606 | * (inefficient). We should create specific code that only target the | |
607 | * added desc. | |
608 | */ | |
609 | int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc) | |
610 | { | |
611 | struct lttng_session *session; | |
612 | ||
613 | cds_list_for_each_entry(session, &sessions, node) { | |
614 | lttng_session_lazy_sync_enablers(session); | |
8020ceb5 | 615 | } |
e58095ef MD |
616 | return 0; |
617 | } | |
618 | ||
619 | /* | |
620 | * Only used internally at session destruction. | |
621 | */ | |
622 | int _lttng_event_unregister(struct lttng_event *event) | |
623 | { | |
624 | return __tracepoint_probe_unregister(event->desc->name, | |
625 | event->desc->probe_callback, | |
626 | event); | |
627 | } | |
628 | ||
629 | /* | |
630 | * Only used internally at session destruction. | |
631 | */ | |
632 | static | |
633 | void _lttng_event_destroy(struct lttng_event *event) | |
634 | { | |
635 | struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref; | |
636 | ||
e58095ef | 637 | cds_list_del(&event->node); |
8020ceb5 | 638 | lttng_destroy_context(event->ctx); |
f488575f | 639 | lttng_free_event_filter_runtime(event); |
e58095ef MD |
640 | /* Free event enabler refs */ |
641 | cds_list_for_each_entry_safe(enabler_ref, tmp_enabler_ref, | |
642 | &event->enablers_ref_head, node) | |
643 | free(enabler_ref); | |
b5234c06 | 644 | free(event); |
8020ceb5 MD |
645 | } |
646 | ||
003fedf4 | 647 | void lttng_ust_events_exit(void) |
8020ceb5 | 648 | { |
7dd08bec | 649 | struct lttng_session *session, *tmpsession; |
8020ceb5 | 650 | |
e58095ef | 651 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, node) |
7dd08bec | 652 | lttng_session_destroy(session); |
8020ceb5 | 653 | } |
457a6b58 | 654 | |
e58095ef MD |
655 | /* |
656 | * Enabler management. | |
657 | */ | |
658 | struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, | |
659 | struct lttng_ust_event *event_param, | |
660 | struct lttng_channel *chan) | |
457a6b58 | 661 | { |
e58095ef MD |
662 | struct lttng_enabler *enabler; |
663 | ||
664 | enabler = zmalloc(sizeof(*enabler)); | |
665 | if (!enabler) | |
666 | return NULL; | |
667 | enabler->type = type; | |
668 | CDS_INIT_LIST_HEAD(&enabler->filter_bytecode_head); | |
669 | memcpy(&enabler->event_param, event_param, | |
670 | sizeof(enabler->event_param)); | |
671 | enabler->chan = chan; | |
672 | /* ctx left NULL */ | |
673 | enabler->enabled = 1; | |
674 | cds_list_add(&enabler->node, &enabler->chan->session->enablers_head); | |
675 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
676 | return enabler; | |
457a6b58 MD |
677 | } |
678 | ||
e58095ef | 679 | int lttng_enabler_enable(struct lttng_enabler *enabler) |
457a6b58 | 680 | { |
e58095ef MD |
681 | enabler->enabled = 1; |
682 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
683 | return 0; | |
457a6b58 | 684 | } |
457a6b58 | 685 | |
e58095ef | 686 | int lttng_enabler_disable(struct lttng_enabler *enabler) |
457a6b58 | 687 | { |
e58095ef MD |
688 | if (enabler->chan == enabler->chan->session->metadata) |
689 | return -EPERM; | |
690 | enabler->enabled = 0; | |
691 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
692 | return 0; | |
693 | } | |
457a6b58 | 694 | |
e58095ef MD |
695 | int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler, |
696 | struct lttng_ust_filter_bytecode_node *bytecode) | |
697 | { | |
698 | bytecode->enabler = enabler; | |
699 | cds_list_add_tail(&bytecode->node, &enabler->filter_bytecode_head); | |
700 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
701 | return 0; | |
702 | } | |
f488575f | 703 | |
e58095ef MD |
704 | int lttng_attach_context(struct lttng_ust_context *context_param, |
705 | struct lttng_ctx **ctx, struct lttng_session *session) | |
706 | { | |
457a6b58 | 707 | /* |
e58095ef MD |
708 | * We cannot attach a context after trace has been started for a |
709 | * session because the metadata does not allow expressing this | |
710 | * information outside of the original channel scope. | |
457a6b58 | 711 | */ |
e58095ef MD |
712 | if (session->been_active) |
713 | return -EPERM; | |
457a6b58 | 714 | |
e58095ef MD |
715 | switch (context_param->ctx) { |
716 | case LTTNG_UST_CONTEXT_PTHREAD_ID: | |
717 | return lttng_add_pthread_id_to_ctx(ctx); | |
718 | case LTTNG_UST_CONTEXT_VTID: | |
719 | return lttng_add_vtid_to_ctx(ctx); | |
720 | case LTTNG_UST_CONTEXT_VPID: | |
721 | return lttng_add_vpid_to_ctx(ctx); | |
722 | case LTTNG_UST_CONTEXT_PROCNAME: | |
723 | return lttng_add_procname_to_ctx(ctx); | |
724 | default: | |
725 | return -EINVAL; | |
457a6b58 | 726 | } |
457a6b58 MD |
727 | } |
728 | ||
e58095ef MD |
729 | int lttng_enabler_attach_context(struct lttng_enabler *enabler, |
730 | struct lttng_ust_context *context_param) | |
457a6b58 | 731 | { |
e58095ef MD |
732 | #if 0 // disabled for now. |
733 | struct lttng_session *session = enabler->chan->session; | |
734 | int ret; | |
457a6b58 | 735 | |
e58095ef MD |
736 | ret = lttng_attach_context(context_param, &enabler->ctx, |
737 | session); | |
738 | if (ret) | |
739 | return ret; | |
740 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
741 | #endif | |
742 | return -ENOSYS; | |
457a6b58 MD |
743 | } |
744 | ||
e58095ef MD |
745 | static |
746 | void lttng_enabler_destroy(struct lttng_enabler *enabler) | |
457a6b58 | 747 | { |
e58095ef | 748 | struct lttng_ust_filter_bytecode_node *filter_node, *tmp_filter_node; |
457a6b58 | 749 | |
e58095ef MD |
750 | /* Destroy filter bytecode */ |
751 | cds_list_for_each_entry_safe(filter_node, tmp_filter_node, | |
752 | &enabler->filter_bytecode_head, node) { | |
753 | free(filter_node); | |
457a6b58 | 754 | } |
e58095ef MD |
755 | |
756 | /* Destroy contexts */ | |
757 | lttng_destroy_context(enabler->ctx); | |
758 | ||
759 | cds_list_del(&enabler->node); | |
760 | free(enabler); | |
457a6b58 MD |
761 | } |
762 | ||
e58095ef MD |
763 | /* |
764 | * lttng_session_sync_enablers should be called just before starting a | |
765 | * session. | |
766 | */ | |
457a6b58 | 767 | static |
e58095ef | 768 | void lttng_session_sync_enablers(struct lttng_session *session) |
457a6b58 | 769 | { |
e58095ef MD |
770 | struct lttng_enabler *enabler; |
771 | struct lttng_event *event; | |
457a6b58 | 772 | |
e58095ef MD |
773 | cds_list_for_each_entry(enabler, &session->enablers_head, node) |
774 | lttng_enabler_ref_events(enabler); | |
775 | /* | |
776 | * For each event, if at least one of its enablers is enabled, | |
777 | * we enable the event, else we disable it. | |
778 | */ | |
779 | cds_list_for_each_entry(event, &session->events_head, node) { | |
780 | struct lttng_enabler_ref *enabler_ref; | |
781 | struct lttng_bytecode_runtime *runtime; | |
dcdeaff0 | 782 | int enabled = 0, has_enablers_without_bytecode = 0; |
e58095ef MD |
783 | |
784 | /* Enable events */ | |
785 | cds_list_for_each_entry(enabler_ref, | |
786 | &event->enablers_ref_head, node) { | |
787 | if (enabler_ref->ref->enabled) { | |
788 | enabled = 1; | |
789 | break; | |
790 | } | |
791 | } | |
792 | event->enabled = enabled; | |
457a6b58 | 793 | |
1f49fc05 | 794 | /* Check if has enablers without bytecode enabled */ |
dcdeaff0 MD |
795 | cds_list_for_each_entry(enabler_ref, |
796 | &event->enablers_ref_head, node) { | |
1f49fc05 MD |
797 | if (enabler_ref->ref->enabled |
798 | && cds_list_empty(&enabler_ref->ref->filter_bytecode_head)) { | |
dcdeaff0 MD |
799 | has_enablers_without_bytecode = 1; |
800 | break; | |
801 | } | |
802 | } | |
803 | event->has_enablers_without_bytecode = | |
804 | has_enablers_without_bytecode; | |
805 | ||
e58095ef MD |
806 | /* Enable filters */ |
807 | cds_list_for_each_entry(runtime, | |
808 | &event->bytecode_runtime_head, node) { | |
809 | lttng_filter_sync_state(runtime); | |
457a6b58 MD |
810 | } |
811 | } | |
457a6b58 MD |
812 | } |
813 | ||
e58095ef MD |
814 | /* |
815 | * Apply enablers to session events, adding events to session if need | |
816 | * be. It is required after each modification applied to an active | |
817 | * session, and right before session "start". | |
818 | * "lazy" sync means we only sync if required. | |
819 | */ | |
820 | static | |
821 | void lttng_session_lazy_sync_enablers(struct lttng_session *session) | |
457a6b58 | 822 | { |
e58095ef MD |
823 | /* We can skip if session is not active */ |
824 | if (!session->active) | |
825 | return; | |
826 | lttng_session_sync_enablers(session); | |
457a6b58 | 827 | } |