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); |
8020ceb5 | 81 | |
e58095ef MD |
82 | static |
83 | void lttng_session_lazy_sync_enablers(struct lttng_session *session); | |
84 | static | |
85 | void lttng_session_sync_enablers(struct lttng_session *session); | |
86 | static | |
87 | void lttng_enabler_destroy(struct lttng_enabler *enabler); | |
88 | ||
6715d7d1 MD |
89 | /* |
90 | * Called with ust lock held. | |
91 | */ | |
92 | int lttng_session_active(void) | |
93 | { | |
94 | struct lttng_session *iter; | |
95 | ||
96 | cds_list_for_each_entry(iter, &sessions, node) { | |
97 | if (iter->active) | |
98 | return 1; | |
99 | } | |
100 | return 0; | |
101 | } | |
102 | ||
e58095ef MD |
103 | static |
104 | int lttng_loglevel_match(int loglevel, | |
105 | unsigned int has_loglevel, | |
457a6b58 MD |
106 | enum lttng_ust_loglevel_type req_type, |
107 | int req_loglevel) | |
108 | { | |
457a6b58 MD |
109 | if (req_type == LTTNG_UST_LOGLEVEL_ALL) |
110 | return 1; | |
e58095ef MD |
111 | if (!has_loglevel) |
112 | loglevel = TRACE_DEFAULT; | |
457a6b58 MD |
113 | switch (req_type) { |
114 | case LTTNG_UST_LOGLEVEL_RANGE: | |
e58095ef | 115 | if (loglevel <= req_loglevel || req_loglevel == -1) |
457a6b58 MD |
116 | return 1; |
117 | else | |
118 | return 0; | |
119 | case LTTNG_UST_LOGLEVEL_SINGLE: | |
e58095ef | 120 | if (loglevel == req_loglevel || req_loglevel == -1) |
457a6b58 MD |
121 | return 1; |
122 | else | |
123 | return 0; | |
124 | case LTTNG_UST_LOGLEVEL_ALL: | |
125 | default: | |
126 | return 1; | |
127 | } | |
128 | } | |
129 | ||
8020ceb5 MD |
130 | void synchronize_trace(void) |
131 | { | |
8020ceb5 | 132 | synchronize_rcu(); |
8020ceb5 MD |
133 | } |
134 | ||
7dd08bec | 135 | struct lttng_session *lttng_session_create(void) |
8020ceb5 | 136 | { |
7dd08bec | 137 | struct lttng_session *session; |
74d81a6c | 138 | int i; |
8020ceb5 | 139 | |
7dd08bec | 140 | session = zmalloc(sizeof(struct lttng_session)); |
8020ceb5 MD |
141 | if (!session) |
142 | return NULL; | |
e58095ef MD |
143 | CDS_INIT_LIST_HEAD(&session->chan_head); |
144 | CDS_INIT_LIST_HEAD(&session->events_head); | |
145 | CDS_INIT_LIST_HEAD(&session->enablers_head); | |
d56fa719 MD |
146 | for (i = 0; i < LTTNG_UST_EVENT_HT_SIZE; i++) |
147 | CDS_INIT_HLIST_HEAD(&session->events_ht.table[i]); | |
e58095ef | 148 | cds_list_add(&session->node, &sessions); |
8020ceb5 MD |
149 | return session; |
150 | } | |
151 | ||
74d81a6c MD |
152 | /* |
153 | * Only used internally at session destruction. | |
154 | */ | |
155 | static | |
156 | void _lttng_channel_unmap(struct lttng_channel *lttng_chan) | |
157 | { | |
158 | struct channel *chan; | |
159 | struct lttng_ust_shm_handle *handle; | |
160 | ||
161 | cds_list_del(<tng_chan->node); | |
162 | lttng_destroy_context(lttng_chan->ctx); | |
163 | chan = lttng_chan->chan; | |
164 | handle = lttng_chan->handle; | |
165 | /* | |
166 | * note: lttng_chan is private data contained within handle. It | |
167 | * will be freed along with the handle. | |
168 | */ | |
169 | channel_destroy(chan, handle, 0); | |
170 | } | |
171 | ||
ac6b4ac6 MD |
172 | static |
173 | void register_event(struct lttng_event *event) | |
174 | { | |
175 | int ret; | |
176 | const struct lttng_event_desc *desc; | |
177 | ||
178 | assert(event->registered == 0); | |
179 | desc = event->desc; | |
180 | ret = __tracepoint_probe_register(desc->name, | |
181 | desc->probe_callback, | |
182 | event, desc->signature); | |
183 | WARN_ON_ONCE(ret); | |
184 | if (!ret) | |
185 | event->registered = 1; | |
186 | } | |
187 | ||
188 | static | |
189 | void unregister_event(struct lttng_event *event) | |
190 | { | |
191 | int ret; | |
192 | const struct lttng_event_desc *desc; | |
193 | ||
194 | assert(event->registered == 1); | |
195 | desc = event->desc; | |
196 | ret = __tracepoint_probe_unregister(desc->name, | |
197 | desc->probe_callback, | |
198 | event); | |
199 | WARN_ON_ONCE(ret); | |
200 | if (!ret) | |
201 | event->registered = 0; | |
202 | } | |
203 | ||
204 | /* | |
205 | * Only used internally at session destruction. | |
206 | */ | |
207 | static | |
208 | void _lttng_event_unregister(struct lttng_event *event) | |
209 | { | |
210 | if (event->registered) | |
211 | unregister_event(event); | |
212 | } | |
213 | ||
7dd08bec | 214 | void lttng_session_destroy(struct lttng_session *session) |
8020ceb5 | 215 | { |
7dd08bec MD |
216 | struct lttng_channel *chan, *tmpchan; |
217 | struct lttng_event *event, *tmpevent; | |
e58095ef | 218 | struct lttng_enabler *enabler, *tmpenabler; |
8020ceb5 | 219 | |
b5234c06 | 220 | CMM_ACCESS_ONCE(session->active) = 0; |
e58095ef | 221 | cds_list_for_each_entry(event, &session->events_head, node) { |
ac6b4ac6 | 222 | _lttng_event_unregister(event); |
8020ceb5 MD |
223 | } |
224 | synchronize_trace(); /* Wait for in-flight events to complete */ | |
e58095ef MD |
225 | cds_list_for_each_entry_safe(enabler, tmpenabler, |
226 | &session->enablers_head, node) | |
227 | lttng_enabler_destroy(enabler); | |
228 | cds_list_for_each_entry_safe(event, tmpevent, | |
229 | &session->events_head, node) | |
7dd08bec | 230 | _lttng_event_destroy(event); |
e58095ef | 231 | cds_list_for_each_entry_safe(chan, tmpchan, &session->chan_head, node) |
74d81a6c | 232 | _lttng_channel_unmap(chan); |
e58095ef | 233 | cds_list_del(&session->node); |
b5234c06 | 234 | free(session); |
8020ceb5 MD |
235 | } |
236 | ||
7dd08bec | 237 | int lttng_session_enable(struct lttng_session *session) |
8020ceb5 MD |
238 | { |
239 | int ret = 0; | |
7dd08bec | 240 | struct lttng_channel *chan; |
32ce8569 | 241 | int notify_socket; |
8020ceb5 | 242 | |
8020ceb5 MD |
243 | if (session->active) { |
244 | ret = -EBUSY; | |
245 | goto end; | |
246 | } | |
247 | ||
32ce8569 MD |
248 | notify_socket = lttng_get_notify_socket(session->owner); |
249 | if (notify_socket < 0) | |
250 | return notify_socket; | |
251 | ||
ac6b4ac6 MD |
252 | /* Set transient enabler state to "enabled" */ |
253 | session->tstate = 1; | |
e58095ef MD |
254 | /* We need to sync enablers with session before activation. */ |
255 | lttng_session_sync_enablers(session); | |
256 | ||
8020ceb5 MD |
257 | /* |
258 | * Snapshot the number of events per channel to know the type of header | |
259 | * we need to use. | |
260 | */ | |
e58095ef | 261 | cds_list_for_each_entry(chan, &session->chan_head, node) { |
32ce8569 MD |
262 | const struct lttng_ctx *ctx; |
263 | const struct lttng_event_field *fields = NULL; | |
264 | size_t nr_fields = 0; | |
265 | ||
266 | /* don't change it if session stop/restart */ | |
8020ceb5 | 267 | if (chan->header_type) |
32ce8569 MD |
268 | continue; |
269 | ctx = chan->ctx; | |
270 | if (ctx) { | |
271 | nr_fields = ctx->nr_fields; | |
272 | fields = &ctx->fields->event_field; | |
273 | } | |
274 | ret = ustcomm_register_channel(notify_socket, | |
275 | session->objd, | |
276 | chan->objd, | |
277 | nr_fields, | |
278 | fields, | |
279 | &chan->id, | |
280 | &chan->header_type); | |
b869b5ae MD |
281 | if (ret) { |
282 | DBG("Error (%d) registering channel to sessiond", ret); | |
32ce8569 | 283 | return ret; |
b869b5ae | 284 | } |
8020ceb5 MD |
285 | } |
286 | ||
ac6b4ac6 | 287 | /* Set atomically the state to "active" */ |
b5234c06 MD |
288 | CMM_ACCESS_ONCE(session->active) = 1; |
289 | CMM_ACCESS_ONCE(session->been_active) = 1; | |
8020ceb5 | 290 | end: |
8020ceb5 MD |
291 | return ret; |
292 | } | |
293 | ||
7dd08bec | 294 | int lttng_session_disable(struct lttng_session *session) |
8020ceb5 MD |
295 | { |
296 | int ret = 0; | |
297 | ||
8020ceb5 MD |
298 | if (!session->active) { |
299 | ret = -EBUSY; | |
300 | goto end; | |
301 | } | |
ac6b4ac6 | 302 | /* Set atomically the state to "inactive" */ |
b5234c06 | 303 | CMM_ACCESS_ONCE(session->active) = 0; |
ac6b4ac6 MD |
304 | |
305 | /* Set transient enabler state to "disabled" */ | |
306 | session->tstate = 0; | |
307 | lttng_session_sync_enablers(session); | |
8020ceb5 | 308 | end: |
8020ceb5 MD |
309 | return ret; |
310 | } | |
311 | ||
7dd08bec | 312 | int lttng_channel_enable(struct lttng_channel *channel) |
976fe9ea | 313 | { |
ac6b4ac6 | 314 | int ret = 0; |
976fe9ea | 315 | |
ac6b4ac6 MD |
316 | if (channel->enabled) { |
317 | ret = -EBUSY; | |
318 | goto end; | |
319 | } | |
320 | /* Set transient enabler state to "enabled" */ | |
321 | channel->tstate = 1; | |
322 | lttng_session_sync_enablers(channel->session); | |
323 | /* Set atomically the state to "enabled" */ | |
324 | CMM_ACCESS_ONCE(channel->enabled) = 1; | |
325 | end: | |
326 | return ret; | |
976fe9ea MD |
327 | } |
328 | ||
7dd08bec | 329 | int lttng_channel_disable(struct lttng_channel *channel) |
976fe9ea | 330 | { |
ac6b4ac6 | 331 | int ret = 0; |
976fe9ea | 332 | |
ac6b4ac6 MD |
333 | if (!channel->enabled) { |
334 | ret = -EBUSY; | |
335 | goto end; | |
336 | } | |
337 | /* Set atomically the state to "disabled" */ | |
338 | CMM_ACCESS_ONCE(channel->enabled) = 0; | |
339 | /* Set transient enabler state to "enabled" */ | |
340 | channel->tstate = 0; | |
341 | lttng_session_sync_enablers(channel->session); | |
342 | end: | |
343 | return ret; | |
976fe9ea MD |
344 | } |
345 | ||
8020ceb5 MD |
346 | /* |
347 | * Supports event creation while tracing session is active. | |
348 | */ | |
e58095ef MD |
349 | static |
350 | int lttng_event_create(const struct lttng_event_desc *desc, | |
351 | struct lttng_channel *chan) | |
8020ceb5 | 352 | { |
e58095ef | 353 | const char *event_name = desc->name; |
7dd08bec | 354 | struct lttng_event *event; |
32ce8569 | 355 | struct lttng_session *session = chan->session; |
d56fa719 MD |
356 | struct cds_hlist_head *head; |
357 | struct cds_hlist_node *node; | |
576599a0 | 358 | int ret = 0; |
d56fa719 MD |
359 | size_t name_len = strlen(event_name); |
360 | uint32_t hash; | |
32ce8569 MD |
361 | int notify_socket, loglevel; |
362 | const char *uri; | |
8020ceb5 | 363 | |
d56fa719 MD |
364 | hash = jhash(event_name, name_len, 0); |
365 | head = &chan->session->events_ht.table[hash & (LTTNG_UST_EVENT_HT_SIZE - 1)]; | |
366 | cds_hlist_for_each_entry(event, node, head, hlist) { | |
e58095ef MD |
367 | assert(event->desc); |
368 | if (!strncmp(event->desc->name, | |
369 | desc->name, | |
ff412fb5 | 370 | LTTNG_UST_SYM_NAME_LEN - 1)) { |
576599a0 | 371 | ret = -EEXIST; |
8020ceb5 | 372 | goto exist; |
576599a0 MD |
373 | } |
374 | } | |
457a6b58 | 375 | |
32ce8569 MD |
376 | notify_socket = lttng_get_notify_socket(session->owner); |
377 | if (notify_socket < 0) { | |
378 | ret = notify_socket; | |
379 | goto socket_error; | |
380 | } | |
381 | ||
457a6b58 MD |
382 | /* |
383 | * Check if loglevel match. Refuse to connect event if not. | |
384 | */ | |
7dd08bec | 385 | event = zmalloc(sizeof(struct lttng_event)); |
576599a0 MD |
386 | if (!event) { |
387 | ret = -ENOMEM; | |
8020ceb5 | 388 | goto cache_error; |
576599a0 | 389 | } |
8020ceb5 | 390 | event->chan = chan; |
e58095ef | 391 | |
ac6b4ac6 MD |
392 | /* Event will be enabled by enabler sync. */ |
393 | event->enabled = 0; | |
394 | event->registered = 0; | |
e58095ef MD |
395 | CDS_INIT_LIST_HEAD(&event->bytecode_runtime_head); |
396 | CDS_INIT_LIST_HEAD(&event->enablers_ref_head); | |
397 | event->desc = desc; | |
32ce8569 MD |
398 | |
399 | if (desc->loglevel) | |
400 | loglevel = *(*event->desc->loglevel); | |
401 | else | |
402 | loglevel = TRACE_DEFAULT; | |
403 | if (desc->u.ext.model_emf_uri) | |
404 | uri = *(desc->u.ext.model_emf_uri); | |
405 | else | |
406 | uri = NULL; | |
407 | ||
13b21cd6 MD |
408 | /* Fetch event ID from sessiond */ |
409 | ret = ustcomm_register_event(notify_socket, | |
410 | session->objd, | |
411 | chan->objd, | |
412 | event_name, | |
413 | loglevel, | |
414 | desc->signature, | |
415 | desc->nr_fields, | |
416 | desc->fields, | |
417 | uri, | |
418 | &event->id); | |
419 | if (ret < 0) { | |
420 | DBG("Error (%d) registering event to sessiond", ret); | |
421 | goto sessiond_register_error; | |
32ce8569 | 422 | } |
2b213b16 | 423 | |
7dd08bec | 424 | /* Populate lttng_event structure before tracepoint registration. */ |
b5234c06 | 425 | cmm_smp_wmb(); |
e58095ef | 426 | cds_list_add(&event->node, &chan->session->events_head); |
d56fa719 | 427 | cds_hlist_add_head(&event->hlist, head); |
576599a0 | 428 | return 0; |
8020ceb5 | 429 | |
32ce8569 | 430 | sessiond_register_error: |
b5234c06 | 431 | free(event); |
8020ceb5 | 432 | cache_error: |
32ce8569 | 433 | socket_error: |
8020ceb5 | 434 | exist: |
576599a0 | 435 | return ret; |
8020ceb5 MD |
436 | } |
437 | ||
e58095ef MD |
438 | static |
439 | int lttng_desc_match_wildcard_enabler(const struct lttng_event_desc *desc, | |
440 | struct lttng_enabler *enabler) | |
441 | { | |
442 | int loglevel = 0; | |
443 | unsigned int has_loglevel; | |
444 | ||
445 | assert(enabler->type == LTTNG_ENABLER_WILDCARD); | |
446 | /* Compare excluding final '*' */ | |
447 | if (strncmp(desc->name, enabler->event_param.name, | |
448 | strlen(enabler->event_param.name) - 1)) | |
449 | return 0; | |
450 | if (desc->loglevel) { | |
451 | loglevel = *(*desc->loglevel); | |
452 | has_loglevel = 1; | |
453 | } | |
454 | if (!lttng_loglevel_match(loglevel, | |
455 | has_loglevel, | |
456 | enabler->event_param.loglevel_type, | |
457 | enabler->event_param.loglevel)) | |
458 | return 0; | |
459 | return 1; | |
460 | } | |
461 | ||
462 | static | |
463 | int lttng_desc_match_event_enabler(const struct lttng_event_desc *desc, | |
464 | struct lttng_enabler *enabler) | |
465 | { | |
466 | int loglevel = 0; | |
467 | unsigned int has_loglevel = 0; | |
468 | ||
469 | assert(enabler->type == LTTNG_ENABLER_EVENT); | |
470 | if (strcmp(desc->name, enabler->event_param.name)) | |
471 | return 0; | |
472 | if (desc->loglevel) { | |
473 | loglevel = *(*desc->loglevel); | |
474 | has_loglevel = 1; | |
475 | } | |
476 | if (!lttng_loglevel_match(loglevel, | |
477 | has_loglevel, | |
478 | enabler->event_param.loglevel_type, | |
479 | enabler->event_param.loglevel)) | |
480 | return 0; | |
481 | return 1; | |
482 | } | |
483 | ||
484 | static | |
485 | int lttng_desc_match_enabler(const struct lttng_event_desc *desc, | |
486 | struct lttng_enabler *enabler) | |
487 | { | |
488 | switch (enabler->type) { | |
489 | case LTTNG_ENABLER_WILDCARD: | |
490 | return lttng_desc_match_wildcard_enabler(desc, enabler); | |
491 | case LTTNG_ENABLER_EVENT: | |
492 | return lttng_desc_match_event_enabler(desc, enabler); | |
493 | default: | |
494 | return -EINVAL; | |
495 | } | |
496 | } | |
497 | ||
498 | static | |
499 | int lttng_event_match_enabler(struct lttng_event *event, | |
500 | struct lttng_enabler *enabler) | |
501 | { | |
502 | return lttng_desc_match_enabler(event->desc, enabler); | |
503 | } | |
504 | ||
505 | static | |
506 | struct lttng_enabler_ref * lttng_event_enabler_ref(struct lttng_event *event, | |
507 | struct lttng_enabler *enabler) | |
508 | { | |
509 | struct lttng_enabler_ref *enabler_ref; | |
510 | ||
511 | cds_list_for_each_entry(enabler_ref, | |
512 | &event->enablers_ref_head, node) { | |
513 | if (enabler_ref->ref == enabler) | |
514 | return enabler_ref; | |
515 | } | |
516 | return NULL; | |
517 | } | |
518 | ||
8020ceb5 | 519 | /* |
e58095ef MD |
520 | * Create struct lttng_event if it is missing and present in the list of |
521 | * tracepoint probes. | |
8020ceb5 | 522 | */ |
e58095ef MD |
523 | static |
524 | void lttng_create_event_if_missing(struct lttng_enabler *enabler) | |
8020ceb5 | 525 | { |
e58095ef MD |
526 | struct lttng_session *session = enabler->chan->session; |
527 | struct lttng_probe_desc *probe_desc; | |
528 | const struct lttng_event_desc *desc; | |
529 | struct lttng_event *event; | |
530 | int i; | |
531 | struct cds_list_head *probe_list; | |
532 | ||
533 | probe_list = lttng_get_probe_list_head(); | |
534 | /* | |
535 | * For each probe event, if we find that a probe event matches | |
536 | * our enabler, create an associated lttng_event if not | |
537 | * already present. | |
538 | */ | |
539 | cds_list_for_each_entry(probe_desc, probe_list, head) { | |
540 | for (i = 0; i < probe_desc->nr_events; i++) { | |
541 | int found = 0, ret; | |
d56fa719 MD |
542 | struct cds_hlist_head *head; |
543 | struct cds_hlist_node *node; | |
544 | const char *event_name; | |
545 | size_t name_len; | |
546 | uint32_t hash; | |
e58095ef MD |
547 | |
548 | desc = probe_desc->event_desc[i]; | |
549 | if (!lttng_desc_match_enabler(desc, enabler)) | |
550 | continue; | |
d56fa719 MD |
551 | event_name = desc->name; |
552 | name_len = strlen(event_name); | |
e58095ef MD |
553 | |
554 | /* | |
d56fa719 | 555 | * Check if already created. |
e58095ef | 556 | */ |
d56fa719 MD |
557 | hash = jhash(event_name, name_len, 0); |
558 | head = &session->events_ht.table[hash & (LTTNG_UST_EVENT_HT_SIZE - 1)]; | |
559 | cds_hlist_for_each_entry(event, node, head, hlist) { | |
e58095ef MD |
560 | if (event->desc == desc) |
561 | found = 1; | |
562 | } | |
563 | if (found) | |
564 | continue; | |
565 | ||
566 | /* | |
567 | * We need to create an event for this | |
568 | * event probe. | |
569 | */ | |
570 | ret = lttng_event_create(probe_desc->event_desc[i], | |
571 | enabler->chan); | |
572 | if (ret) { | |
32ce8569 MD |
573 | DBG("Unable to create event %s, error %d\n", |
574 | probe_desc->event_desc[i]->name, ret); | |
e58095ef | 575 | } |
8165c8da | 576 | } |
8020ceb5 | 577 | } |
8020ceb5 MD |
578 | } |
579 | ||
580 | /* | |
e58095ef MD |
581 | * Create events associated with an enabler (if not already present), |
582 | * and add backward reference from the event to the enabler. | |
8020ceb5 MD |
583 | */ |
584 | static | |
e58095ef | 585 | int lttng_enabler_ref_events(struct lttng_enabler *enabler) |
8020ceb5 | 586 | { |
e58095ef MD |
587 | struct lttng_session *session = enabler->chan->session; |
588 | struct lttng_event *event; | |
589 | ||
590 | /* First ensure that probe events are created for this enabler. */ | |
591 | lttng_create_event_if_missing(enabler); | |
592 | ||
593 | /* For each event matching enabler in session event list. */ | |
594 | cds_list_for_each_entry(event, &session->events_head, node) { | |
595 | struct lttng_enabler_ref *enabler_ref; | |
596 | ||
597 | if (!lttng_event_match_enabler(event, enabler)) | |
598 | continue; | |
599 | ||
600 | enabler_ref = lttng_event_enabler_ref(event, enabler); | |
601 | if (!enabler_ref) { | |
602 | /* | |
603 | * If no backward ref, create it. | |
604 | * Add backward ref from event to enabler. | |
605 | */ | |
606 | enabler_ref = zmalloc(sizeof(*enabler_ref)); | |
607 | if (!enabler_ref) | |
608 | return -ENOMEM; | |
609 | enabler_ref->ref = enabler; | |
610 | cds_list_add(&enabler_ref->node, | |
611 | &event->enablers_ref_head); | |
8165c8da | 612 | } |
e58095ef MD |
613 | |
614 | /* | |
615 | * Link filter bytecodes if not linked yet. | |
616 | */ | |
617 | lttng_enabler_event_link_bytecode(event, enabler); | |
618 | ||
619 | /* TODO: merge event context. */ | |
620 | } | |
621 | return 0; | |
622 | } | |
623 | ||
624 | /* | |
625 | * Called at library load: connect the probe on all enablers matching | |
626 | * this event. | |
627 | * called with session mutex held. | |
628 | * TODO: currently, for each desc added, we iterate on all event desc | |
629 | * (inefficient). We should create specific code that only target the | |
630 | * added desc. | |
631 | */ | |
632 | int lttng_fix_pending_event_desc(const struct lttng_event_desc *desc) | |
633 | { | |
634 | struct lttng_session *session; | |
635 | ||
636 | cds_list_for_each_entry(session, &sessions, node) { | |
637 | lttng_session_lazy_sync_enablers(session); | |
8020ceb5 | 638 | } |
e58095ef MD |
639 | return 0; |
640 | } | |
641 | ||
e58095ef MD |
642 | /* |
643 | * Only used internally at session destruction. | |
644 | */ | |
645 | static | |
646 | void _lttng_event_destroy(struct lttng_event *event) | |
647 | { | |
648 | struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref; | |
649 | ||
e58095ef | 650 | cds_list_del(&event->node); |
8020ceb5 | 651 | lttng_destroy_context(event->ctx); |
f488575f | 652 | lttng_free_event_filter_runtime(event); |
e58095ef MD |
653 | /* Free event enabler refs */ |
654 | cds_list_for_each_entry_safe(enabler_ref, tmp_enabler_ref, | |
655 | &event->enablers_ref_head, node) | |
656 | free(enabler_ref); | |
b5234c06 | 657 | free(event); |
8020ceb5 MD |
658 | } |
659 | ||
003fedf4 | 660 | void lttng_ust_events_exit(void) |
8020ceb5 | 661 | { |
7dd08bec | 662 | struct lttng_session *session, *tmpsession; |
8020ceb5 | 663 | |
e58095ef | 664 | cds_list_for_each_entry_safe(session, tmpsession, &sessions, node) |
7dd08bec | 665 | lttng_session_destroy(session); |
8020ceb5 | 666 | } |
457a6b58 | 667 | |
e58095ef MD |
668 | /* |
669 | * Enabler management. | |
670 | */ | |
671 | struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, | |
672 | struct lttng_ust_event *event_param, | |
673 | struct lttng_channel *chan) | |
457a6b58 | 674 | { |
e58095ef MD |
675 | struct lttng_enabler *enabler; |
676 | ||
677 | enabler = zmalloc(sizeof(*enabler)); | |
678 | if (!enabler) | |
679 | return NULL; | |
680 | enabler->type = type; | |
681 | CDS_INIT_LIST_HEAD(&enabler->filter_bytecode_head); | |
682 | memcpy(&enabler->event_param, event_param, | |
683 | sizeof(enabler->event_param)); | |
684 | enabler->chan = chan; | |
685 | /* ctx left NULL */ | |
686 | enabler->enabled = 1; | |
687 | cds_list_add(&enabler->node, &enabler->chan->session->enablers_head); | |
688 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
689 | return enabler; | |
457a6b58 MD |
690 | } |
691 | ||
e58095ef | 692 | int lttng_enabler_enable(struct lttng_enabler *enabler) |
457a6b58 | 693 | { |
e58095ef MD |
694 | enabler->enabled = 1; |
695 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
696 | return 0; | |
457a6b58 | 697 | } |
457a6b58 | 698 | |
e58095ef | 699 | int lttng_enabler_disable(struct lttng_enabler *enabler) |
457a6b58 | 700 | { |
e58095ef MD |
701 | enabler->enabled = 0; |
702 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
703 | return 0; | |
704 | } | |
457a6b58 | 705 | |
e58095ef MD |
706 | int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler, |
707 | struct lttng_ust_filter_bytecode_node *bytecode) | |
708 | { | |
709 | bytecode->enabler = enabler; | |
710 | cds_list_add_tail(&bytecode->node, &enabler->filter_bytecode_head); | |
711 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
712 | return 0; | |
713 | } | |
f488575f | 714 | |
e58095ef MD |
715 | int lttng_attach_context(struct lttng_ust_context *context_param, |
716 | struct lttng_ctx **ctx, struct lttng_session *session) | |
717 | { | |
457a6b58 | 718 | /* |
e58095ef MD |
719 | * We cannot attach a context after trace has been started for a |
720 | * session because the metadata does not allow expressing this | |
721 | * information outside of the original channel scope. | |
457a6b58 | 722 | */ |
e58095ef MD |
723 | if (session->been_active) |
724 | return -EPERM; | |
457a6b58 | 725 | |
e58095ef MD |
726 | switch (context_param->ctx) { |
727 | case LTTNG_UST_CONTEXT_PTHREAD_ID: | |
728 | return lttng_add_pthread_id_to_ctx(ctx); | |
729 | case LTTNG_UST_CONTEXT_VTID: | |
730 | return lttng_add_vtid_to_ctx(ctx); | |
731 | case LTTNG_UST_CONTEXT_VPID: | |
732 | return lttng_add_vpid_to_ctx(ctx); | |
733 | case LTTNG_UST_CONTEXT_PROCNAME: | |
734 | return lttng_add_procname_to_ctx(ctx); | |
735 | default: | |
736 | return -EINVAL; | |
457a6b58 | 737 | } |
457a6b58 MD |
738 | } |
739 | ||
e58095ef MD |
740 | int lttng_enabler_attach_context(struct lttng_enabler *enabler, |
741 | struct lttng_ust_context *context_param) | |
457a6b58 | 742 | { |
e58095ef MD |
743 | #if 0 // disabled for now. |
744 | struct lttng_session *session = enabler->chan->session; | |
745 | int ret; | |
457a6b58 | 746 | |
e58095ef MD |
747 | ret = lttng_attach_context(context_param, &enabler->ctx, |
748 | session); | |
749 | if (ret) | |
750 | return ret; | |
751 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
752 | #endif | |
753 | return -ENOSYS; | |
457a6b58 MD |
754 | } |
755 | ||
e58095ef MD |
756 | static |
757 | void lttng_enabler_destroy(struct lttng_enabler *enabler) | |
457a6b58 | 758 | { |
e58095ef | 759 | struct lttng_ust_filter_bytecode_node *filter_node, *tmp_filter_node; |
457a6b58 | 760 | |
e58095ef MD |
761 | /* Destroy filter bytecode */ |
762 | cds_list_for_each_entry_safe(filter_node, tmp_filter_node, | |
763 | &enabler->filter_bytecode_head, node) { | |
764 | free(filter_node); | |
457a6b58 | 765 | } |
e58095ef MD |
766 | |
767 | /* Destroy contexts */ | |
768 | lttng_destroy_context(enabler->ctx); | |
769 | ||
770 | cds_list_del(&enabler->node); | |
771 | free(enabler); | |
457a6b58 MD |
772 | } |
773 | ||
e58095ef MD |
774 | /* |
775 | * lttng_session_sync_enablers should be called just before starting a | |
776 | * session. | |
777 | */ | |
457a6b58 | 778 | static |
e58095ef | 779 | void lttng_session_sync_enablers(struct lttng_session *session) |
457a6b58 | 780 | { |
e58095ef MD |
781 | struct lttng_enabler *enabler; |
782 | struct lttng_event *event; | |
457a6b58 | 783 | |
e58095ef MD |
784 | cds_list_for_each_entry(enabler, &session->enablers_head, node) |
785 | lttng_enabler_ref_events(enabler); | |
786 | /* | |
787 | * For each event, if at least one of its enablers is enabled, | |
ac6b4ac6 MD |
788 | * and its channel and session transient states are enabled, we |
789 | * enable the event, else we disable it. | |
e58095ef MD |
790 | */ |
791 | cds_list_for_each_entry(event, &session->events_head, node) { | |
792 | struct lttng_enabler_ref *enabler_ref; | |
793 | struct lttng_bytecode_runtime *runtime; | |
dcdeaff0 | 794 | int enabled = 0, has_enablers_without_bytecode = 0; |
e58095ef MD |
795 | |
796 | /* Enable events */ | |
797 | cds_list_for_each_entry(enabler_ref, | |
798 | &event->enablers_ref_head, node) { | |
799 | if (enabler_ref->ref->enabled) { | |
800 | enabled = 1; | |
801 | break; | |
802 | } | |
803 | } | |
ac6b4ac6 MD |
804 | /* |
805 | * Enabled state is based on union of enablers, with | |
806 | * intesection of session and channel transient enable | |
807 | * states. | |
808 | */ | |
809 | enabled = enabled && session->tstate && event->chan->tstate; | |
810 | ||
811 | CMM_STORE_SHARED(event->enabled, enabled); | |
812 | /* | |
813 | * Sync tracepoint registration with event enabled | |
814 | * state. | |
815 | */ | |
816 | if (enabled) { | |
817 | if (!event->registered) | |
818 | register_event(event); | |
819 | } else { | |
820 | if (event->registered) | |
821 | unregister_event(event); | |
822 | } | |
457a6b58 | 823 | |
1f49fc05 | 824 | /* Check if has enablers without bytecode enabled */ |
dcdeaff0 MD |
825 | cds_list_for_each_entry(enabler_ref, |
826 | &event->enablers_ref_head, node) { | |
1f49fc05 MD |
827 | if (enabler_ref->ref->enabled |
828 | && cds_list_empty(&enabler_ref->ref->filter_bytecode_head)) { | |
dcdeaff0 MD |
829 | has_enablers_without_bytecode = 1; |
830 | break; | |
831 | } | |
832 | } | |
833 | event->has_enablers_without_bytecode = | |
834 | has_enablers_without_bytecode; | |
835 | ||
e58095ef MD |
836 | /* Enable filters */ |
837 | cds_list_for_each_entry(runtime, | |
838 | &event->bytecode_runtime_head, node) { | |
839 | lttng_filter_sync_state(runtime); | |
457a6b58 MD |
840 | } |
841 | } | |
457a6b58 MD |
842 | } |
843 | ||
e58095ef MD |
844 | /* |
845 | * Apply enablers to session events, adding events to session if need | |
846 | * be. It is required after each modification applied to an active | |
847 | * session, and right before session "start". | |
848 | * "lazy" sync means we only sync if required. | |
849 | */ | |
850 | static | |
851 | void lttng_session_lazy_sync_enablers(struct lttng_session *session) | |
457a6b58 | 852 | { |
e58095ef MD |
853 | /* We can skip if session is not active */ |
854 | if (!session->active) | |
855 | return; | |
856 | lttng_session_sync_enablers(session); | |
457a6b58 | 857 | } |