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f4681817 MD |
1 | /* |
2 | * lttng-ust-abi.c | |
3 | * | |
4 | * Copyright 2010-2011 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * LTTng UST ABI | |
7 | * | |
8 | * Mimic system calls for: | |
9 | * - session creation, returns an object descriptor or failure. | |
10 | * - channel creation, returns an object descriptor or failure. | |
11 | * - Operates on a session object descriptor | |
12 | * - Takes all channel options as parameters. | |
13 | * - stream get, returns an object descriptor or failure. | |
14 | * - Operates on a channel object descriptor. | |
15 | * - stream notifier get, returns an object descriptor or failure. | |
16 | * - Operates on a channel object descriptor. | |
17 | * - event creation, returns an object descriptor or failure. | |
18 | * - Operates on a channel object descriptor | |
19 | * - Takes an event name as parameter | |
20 | * - Takes an instrumentation source as parameter | |
21 | * - e.g. tracepoints, dynamic_probes... | |
22 | * - Takes instrumentation source specific arguments. | |
23 | * | |
24 | * Dual LGPL v2.1/GPL v2 license. | |
25 | */ | |
26 | ||
27 | #include <ust/lttng-ust-abi.h> | |
28 | #include <urcu/compiler.h> | |
29 | #include <urcu/list.h> | |
30 | #include <ust/lttng-events.h> | |
1dbfff0c | 31 | #include <ust/usterr-signal-safe.h> |
f4681817 MD |
32 | #include "ust/core.h" |
33 | #include "ltt-tracer.h" | |
34 | ||
35 | /* | |
36 | * Object descriptor table. Should be protected from concurrent access | |
37 | * by the caller. | |
38 | */ | |
39 | ||
40 | struct obj; | |
41 | ||
42 | struct objd_ops { | |
43 | long (*cmd)(int objd, unsigned int cmd, unsigned long arg); | |
44 | int (*release)(int objd); | |
45 | }; | |
46 | ||
47 | struct obj { | |
48 | union { | |
49 | struct { | |
50 | void *private_data; | |
51 | const struct objd_ops *ops; | |
52 | int f_count; | |
53 | } s; | |
54 | int freelist_next; /* offset freelist. end is -1. */ | |
55 | } u; | |
56 | }; | |
57 | ||
58 | struct objd_table { | |
59 | struct obj *array; | |
60 | unsigned int len, allocated_len; | |
61 | int freelist_head; /* offset freelist head. end is -1 */ | |
62 | }; | |
63 | ||
64 | static struct objd_table objd_table = { | |
65 | .freelist_head = -1, | |
66 | }; | |
67 | ||
68 | static | |
69 | int objd_alloc(void *private_data, const struct objd_ops *ops) | |
70 | { | |
71 | struct obj *obj; | |
72 | ||
73 | if (objd_table.freelist_head != -1) { | |
74 | obj = &objd_table.array[objd_table.freelist_head]; | |
75 | objd_table.freelist_head = obj->u.freelist_next; | |
76 | goto end; | |
77 | } | |
78 | ||
79 | if (objd_table.len >= objd_table.allocated_len) { | |
80 | unsigned int new_allocated_len, old_allocated_len; | |
81 | struct obj *new_table, *old_table; | |
82 | ||
83 | old_allocated_len = objd_table.allocated_len; | |
84 | old_table = objd_table.array; | |
85 | if (!old_allocated_len) | |
86 | new_allocated_len = 1; | |
87 | else | |
88 | new_allocated_len = old_allocated_len << 1; | |
89 | new_table = zmalloc(sizeof(struct obj) * new_allocated_len); | |
90 | if (!new_table) | |
91 | return -ENOMEM; | |
92 | memcpy(new_table, old_table, | |
93 | sizeof(struct obj) * old_allocated_len); | |
94 | free(old_table); | |
95 | objd_table.array = new_table; | |
96 | objd_table.allocated_len = new_allocated_len; | |
97 | } | |
98 | obj = &objd_table.array[objd_table.len]; | |
99 | objd_table.len++; | |
100 | end: | |
101 | obj->u.s.private_data = private_data; | |
102 | obj->u.s.ops = ops; | |
103 | obj->u.s.f_count = 1; | |
104 | return obj - objd_table.array; | |
105 | } | |
106 | ||
107 | static | |
108 | struct obj *_objd_get(int id) | |
109 | { | |
110 | if (id >= objd_table.len) | |
111 | return NULL; | |
112 | return &objd_table.array[id]; | |
113 | } | |
114 | ||
115 | static | |
116 | void *objd_private(int id) | |
117 | { | |
118 | struct obj *obj = _objd_get(id); | |
119 | assert(obj); | |
120 | return obj->u.s.private_data; | |
121 | } | |
122 | ||
123 | static | |
124 | void objd_set_private(int id, void *private_data) | |
125 | { | |
126 | struct obj *obj = _objd_get(id); | |
127 | assert(obj); | |
128 | obj->u.s.private_data = private_data; | |
129 | } | |
130 | ||
131 | static | |
132 | const struct objd_ops *objd_ops(int id) | |
133 | { | |
134 | struct obj *obj = _objd_get(id); | |
135 | assert(obj); | |
136 | return obj->u.s.ops; | |
137 | } | |
138 | ||
139 | static | |
140 | void objd_free(int id) | |
141 | { | |
142 | struct obj *obj = _objd_get(id); | |
143 | ||
144 | assert(obj); | |
145 | obj->u.freelist_next = objd_table.freelist_head; | |
146 | objd_table.freelist_head = obj - objd_table.array; | |
147 | } | |
148 | ||
149 | static | |
150 | void objd_ref(int id) | |
151 | { | |
152 | struct obj *obj = _objd_get(id); | |
153 | obj->u.s.f_count++; | |
154 | } | |
155 | ||
156 | static | |
157 | void objd_unref(int id) | |
158 | { | |
159 | struct obj *obj = _objd_get(id); | |
160 | ||
161 | if (!(--obj->u.s.f_count)) { | |
162 | const struct objd_ops *ops = objd_ops(id); | |
163 | ||
164 | if (ops->release) | |
165 | ops->release(id); | |
166 | objd_free(id); | |
167 | } | |
168 | } | |
169 | ||
170 | static | |
171 | void objd_table_destroy(void) | |
172 | { | |
173 | free(objd_table.array); | |
174 | } | |
175 | ||
176 | /* | |
177 | * This is LTTng's own personal way to create an ABI for sessiond. | |
178 | * We send commands over a socket. | |
179 | */ | |
180 | ||
181 | static const struct objd_ops lttng_ops; | |
182 | static const struct objd_ops lttng_session_ops; | |
183 | static const struct objd_ops lttng_channel_ops; | |
184 | static const struct objd_ops lttng_metadata_ops; | |
185 | static const struct objd_ops lttng_event_ops; | |
186 | ||
187 | enum channel_type { | |
188 | PER_CPU_CHANNEL, | |
189 | METADATA_CHANNEL, | |
190 | }; | |
191 | ||
192 | static | |
193 | int lttng_abi_create_session(void) | |
194 | { | |
195 | struct ltt_session *session; | |
196 | int session_objd, ret; | |
197 | ||
198 | session = ltt_session_create(); | |
199 | if (!session) | |
200 | return -ENOMEM; | |
201 | session_objd = objd_alloc(session, <tng_session_ops); | |
202 | if (session_objd < 0) { | |
203 | ret = session_objd; | |
204 | goto objd_error; | |
205 | } | |
206 | session->objd = session_objd; | |
207 | return session_objd; | |
208 | ||
209 | objd_error: | |
210 | ltt_session_destroy(session); | |
211 | return ret; | |
212 | } | |
213 | ||
214 | #if 0 | |
215 | static | |
216 | int lttng_abi_tracepoint_list(void) | |
217 | { | |
218 | int list_objd, ret; | |
219 | ||
220 | /* TODO: Create list private data */ | |
221 | list_objd = objd_alloc(NULL, <tng_tracepoint_list_ops); | |
222 | if (list_objd < 0) { | |
223 | ret = list_objd; | |
224 | goto objd_error; | |
225 | } | |
226 | ||
227 | return list_objd; | |
228 | ||
229 | objd_error: | |
230 | return ret; | |
231 | } | |
232 | #endif //0 | |
233 | ||
234 | static | |
235 | long lttng_abi_tracer_version(int objd, | |
236 | struct lttng_ust_tracer_version *v) | |
237 | { | |
238 | v->version = LTTNG_UST_VERSION; | |
239 | v->patchlevel = LTTNG_UST_PATCHLEVEL; | |
240 | v->sublevel = LTTNG_UST_SUBLEVEL; | |
241 | return 0; | |
242 | } | |
243 | ||
244 | static | |
245 | long lttng_abi_add_context(int objd, | |
246 | struct lttng_ust_context *context_param, | |
247 | struct lttng_ctx **ctx, struct ltt_session *session) | |
248 | { | |
249 | if (session->been_active) | |
250 | return -EPERM; | |
251 | ||
252 | switch (context_param->ctx) { | |
253 | case LTTNG_UST_CONTEXT_VTID: | |
438bc215 | 254 | //TODO return lttng_add_vtid_to_ctx(ctx); |
f4681817 MD |
255 | default: |
256 | return -EINVAL; | |
257 | } | |
258 | } | |
259 | ||
260 | /** | |
261 | * lttng_cmd - lttng control through socket commands | |
262 | * | |
263 | * @objd: the object descriptor | |
264 | * @cmd: the command | |
265 | * @arg: command arg | |
266 | * | |
267 | * This descriptor implements lttng commands: | |
268 | * LTTNG_UST_SESSION | |
269 | * Returns a LTTng trace session object descriptor | |
270 | * LTTNG_UST_TRACER_VERSION | |
271 | * Returns the LTTng kernel tracer version | |
272 | * LTTNG_UST_TRACEPOINT_LIST | |
273 | * Returns a file descriptor listing available tracepoints | |
274 | * LTTNG_UST_WAIT_QUIESCENT | |
275 | * Returns after all previously running probes have completed | |
276 | * | |
277 | * The returned session will be deleted when its file descriptor is closed. | |
278 | */ | |
279 | static | |
280 | long lttng_cmd(int objd, unsigned int cmd, unsigned long arg) | |
281 | { | |
282 | switch (cmd) { | |
283 | case LTTNG_UST_SESSION: | |
284 | return lttng_abi_create_session(); | |
285 | case LTTNG_UST_TRACER_VERSION: | |
286 | return lttng_abi_tracer_version(objd, | |
287 | (struct lttng_ust_tracer_version *) arg); | |
288 | case LTTNG_UST_TRACEPOINT_LIST: | |
289 | return -ENOSYS; //TODO | |
290 | //return lttng_abi_tracepoint_list(); | |
291 | case LTTNG_UST_WAIT_QUIESCENT: | |
292 | synchronize_trace(); | |
293 | return 0; | |
294 | default: | |
295 | return -EINVAL; | |
296 | } | |
297 | } | |
298 | ||
299 | static const struct objd_ops lttng_ops = { | |
300 | .cmd = lttng_cmd, | |
301 | }; | |
302 | ||
303 | /* | |
304 | * We tolerate no failure in this function (if one happens, we print a dmesg | |
305 | * error, but cannot return any error, because the channel information is | |
306 | * invariant. | |
307 | */ | |
308 | static | |
309 | void lttng_metadata_create_events(int channel_objd) | |
310 | { | |
311 | struct ltt_channel *channel = objd_private(channel_objd); | |
312 | static struct lttng_ust_event metadata_params = { | |
313 | .instrumentation = LTTNG_UST_TRACEPOINT, | |
314 | .name = "lttng_metadata", | |
315 | }; | |
316 | struct ltt_event *event; | |
317 | int ret; | |
318 | ||
319 | /* | |
320 | * We tolerate no failure path after event creation. It will stay | |
321 | * invariant for the rest of the session. | |
322 | */ | |
323 | event = ltt_event_create(channel, &metadata_params, NULL); | |
324 | if (!event) { | |
325 | ret = -EINVAL; | |
326 | goto create_error; | |
327 | } | |
328 | return; | |
329 | ||
330 | create_error: | |
331 | WARN_ON(1); | |
332 | return; /* not allowed to return error */ | |
333 | } | |
334 | ||
335 | static | |
336 | int lttng_abi_create_channel(int session_objd, | |
337 | struct lttng_ust_channel *chan_param, | |
338 | enum channel_type channel_type) | |
339 | { | |
340 | struct ltt_session *session = objd_private(session_objd); | |
341 | const struct objd_ops *ops; | |
342 | const char *transport_name; | |
343 | struct ltt_channel *chan; | |
344 | int chan_objd; | |
345 | int ret = 0; | |
346 | ||
347 | chan_objd = objd_alloc(NULL, <tng_channel_ops); | |
348 | if (chan_objd < 0) { | |
349 | ret = chan_objd; | |
350 | goto objd_error; | |
351 | } | |
352 | switch (channel_type) { | |
353 | case PER_CPU_CHANNEL: | |
354 | if (chan_param->output == LTTNG_UST_MMAP) { | |
355 | transport_name = chan_param->overwrite ? | |
356 | "relay-overwrite-mmap" : "relay-discard-mmap"; | |
357 | } else { | |
358 | return -EINVAL; | |
359 | } | |
360 | ops = <tng_channel_ops; | |
361 | break; | |
362 | case METADATA_CHANNEL: | |
363 | if (chan_param->output == LTTNG_UST_MMAP) | |
364 | transport_name = "relay-metadata-mmap"; | |
365 | else | |
366 | return -EINVAL; | |
367 | ops = <tng_metadata_ops; | |
368 | break; | |
369 | default: | |
370 | transport_name = "<unknown>"; | |
371 | break; | |
372 | } | |
373 | /* | |
374 | * We tolerate no failure path after channel creation. It will stay | |
375 | * invariant for the rest of the session. | |
376 | */ | |
377 | chan = ltt_channel_create(session, transport_name, NULL, | |
378 | chan_param->subbuf_size, | |
379 | chan_param->num_subbuf, | |
380 | chan_param->switch_timer_interval, | |
381 | chan_param->read_timer_interval); | |
382 | if (!chan) { | |
383 | ret = -EINVAL; | |
384 | goto chan_error; | |
385 | } | |
386 | objd_set_private(chan_objd, chan); | |
387 | chan->objd = chan_objd; | |
388 | if (channel_type == METADATA_CHANNEL) { | |
389 | session->metadata = chan; | |
390 | lttng_metadata_create_events(chan_objd); | |
391 | } | |
392 | ||
393 | /* The channel created holds a reference on the session */ | |
394 | objd_ref(session_objd); | |
395 | ||
396 | return chan_objd; | |
397 | ||
398 | chan_error: | |
399 | objd_unref(chan_objd); | |
400 | objd_error: | |
401 | return ret; | |
402 | } | |
403 | ||
404 | /** | |
405 | * lttng_session_cmd - lttng session object command | |
406 | * | |
407 | * @obj: the object | |
408 | * @cmd: the command | |
409 | * @arg: command arg | |
410 | * | |
411 | * This descriptor implements lttng commands: | |
412 | * LTTNG_UST_CHANNEL | |
413 | * Returns a LTTng channel object descriptor | |
414 | * LTTNG_UST_ENABLE | |
415 | * Enables tracing for a session (weak enable) | |
416 | * LTTNG_UST_DISABLE | |
417 | * Disables tracing for a session (strong disable) | |
418 | * LTTNG_UST_METADATA | |
419 | * Returns a LTTng metadata object descriptor | |
420 | * | |
421 | * The returned channel will be deleted when its file descriptor is closed. | |
422 | */ | |
423 | static | |
424 | long lttng_session_cmd(int objd, unsigned int cmd, unsigned long arg) | |
425 | { | |
426 | struct ltt_session *session = objd_private(objd); | |
427 | ||
428 | switch (cmd) { | |
429 | case LTTNG_UST_CHANNEL: | |
430 | return lttng_abi_create_channel(objd, | |
431 | (struct lttng_ust_channel *) arg, | |
432 | PER_CPU_CHANNEL); | |
433 | case LTTNG_UST_SESSION_START: | |
434 | case LTTNG_UST_ENABLE: | |
435 | return ltt_session_enable(session); | |
436 | case LTTNG_UST_SESSION_STOP: | |
437 | case LTTNG_UST_DISABLE: | |
438 | return ltt_session_disable(session); | |
439 | case LTTNG_UST_METADATA: | |
440 | return lttng_abi_create_channel(objd, | |
441 | (struct lttng_ust_channel *) arg, | |
442 | METADATA_CHANNEL); | |
443 | default: | |
444 | return -EINVAL; | |
445 | } | |
446 | } | |
447 | ||
448 | /* | |
449 | * Called when the last file reference is dropped. | |
450 | * | |
451 | * Big fat note: channels and events are invariant for the whole session after | |
452 | * their creation. So this session destruction also destroys all channel and | |
453 | * event structures specific to this session (they are not destroyed when their | |
454 | * individual file is released). | |
455 | */ | |
456 | static | |
457 | int lttng_session_release(int objd) | |
458 | { | |
459 | struct ltt_session *session = objd_private(objd); | |
460 | ||
461 | if (session) | |
462 | ltt_session_destroy(session); | |
463 | return 0; | |
464 | } | |
465 | ||
466 | static const struct objd_ops lttng_session_ops = { | |
467 | .release = lttng_session_release, | |
468 | .cmd = lttng_session_cmd, | |
469 | }; | |
470 | ||
471 | #if 0 | |
472 | static | |
473 | int lttng_abi_open_stream(int channel_objd) | |
474 | { | |
475 | struct ltt_channel *channel = objd_private(channel_objd); | |
476 | struct lib_ring_buffer *buf; | |
477 | int stream_objd, ret; | |
478 | ||
479 | buf = channel->ops->buffer_read_open(channel->chan); | |
480 | if (!buf) | |
481 | return -ENOENT; | |
482 | ||
483 | stream_objd = objd_alloc(buf, &lib_ring_buffer_objd_ops); | |
484 | if (stream_objd < 0) { | |
485 | ret = stream_objd; | |
486 | goto objd_error; | |
487 | } | |
488 | /* | |
489 | * The stream holds a reference to the channel within the generic ring | |
490 | * buffer library, so no need to hold a refcount on the channel and | |
491 | * session files here. | |
492 | */ | |
493 | return stream_objd; | |
494 | ||
495 | objd_error: | |
496 | channel->ops->buffer_read_close(buf); | |
497 | return ret; | |
498 | } | |
499 | #endif //0 | |
500 | ||
501 | static | |
502 | int lttng_abi_create_event(int channel_objd, | |
503 | struct lttng_ust_event *event_param) | |
504 | { | |
505 | struct ltt_channel *channel = objd_private(channel_objd); | |
506 | struct ltt_event *event; | |
507 | int event_objd, ret; | |
508 | ||
509 | event_param->name[LTTNG_UST_SYM_NAME_LEN - 1] = '\0'; | |
510 | event_objd = objd_alloc(NULL, <tng_event_ops); | |
511 | if (event_objd < 0) { | |
512 | ret = event_objd; | |
513 | goto objd_error; | |
514 | } | |
515 | /* | |
516 | * We tolerate no failure path after event creation. It will stay | |
517 | * invariant for the rest of the session. | |
518 | */ | |
519 | event = ltt_event_create(channel, event_param, NULL); | |
520 | if (!event) { | |
521 | ret = -EINVAL; | |
522 | goto event_error; | |
523 | } | |
524 | objd_set_private(event_objd, event); | |
525 | /* The event holds a reference on the channel */ | |
526 | objd_ref(channel_objd); | |
527 | return event_objd; | |
528 | ||
529 | event_error: | |
530 | objd_unref(event_objd); | |
531 | objd_error: | |
532 | return ret; | |
533 | } | |
534 | ||
535 | /** | |
536 | * lttng_channel_cmd - lttng control through object descriptors | |
537 | * | |
538 | * @objd: the object descriptor | |
539 | * @cmd: the command | |
540 | * @arg: command arg | |
541 | * | |
542 | * This object descriptor implements lttng commands: | |
543 | * LTTNG_UST_STREAM | |
544 | * Returns an event stream object descriptor or failure. | |
545 | * (typically, one event stream records events from one CPU) | |
546 | * LTTNG_UST_EVENT | |
547 | * Returns an event object descriptor or failure. | |
548 | * LTTNG_UST_CONTEXT | |
549 | * Prepend a context field to each event in the channel | |
550 | * LTTNG_UST_ENABLE | |
551 | * Enable recording for events in this channel (weak enable) | |
552 | * LTTNG_UST_DISABLE | |
553 | * Disable recording for events in this channel (strong disable) | |
554 | * | |
555 | * Channel and event file descriptors also hold a reference on the session. | |
556 | */ | |
557 | static | |
558 | long lttng_channel_cmd(int objd, unsigned int cmd, unsigned long arg) | |
559 | { | |
560 | struct ltt_channel *channel = objd_private(objd); | |
561 | ||
562 | switch (cmd) { | |
563 | case LTTNG_UST_STREAM: | |
564 | return -ENOSYS; //TODO | |
565 | //return lttng_abi_open_stream(objd); | |
566 | case LTTNG_UST_EVENT: | |
567 | return lttng_abi_create_event(objd, (struct lttng_ust_event *) arg); | |
568 | case LTTNG_UST_CONTEXT: | |
569 | return lttng_abi_add_context(objd, | |
570 | (struct lttng_ust_context *) arg, | |
571 | &channel->ctx, channel->session); | |
572 | case LTTNG_UST_ENABLE: | |
573 | return ltt_channel_enable(channel); | |
574 | case LTTNG_UST_DISABLE: | |
575 | return ltt_channel_disable(channel); | |
576 | default: | |
577 | return -EINVAL; | |
578 | } | |
579 | } | |
580 | ||
581 | /** | |
582 | * lttng_metadata_cmd - lttng control through object descriptors | |
583 | * | |
584 | * @objd: the object descriptor | |
585 | * @cmd: the command | |
586 | * @arg: command arg | |
587 | * | |
588 | * This object descriptor implements lttng commands: | |
589 | * LTTNG_UST_STREAM | |
590 | * Returns an event stream file descriptor or failure. | |
591 | * | |
592 | * Channel and event file descriptors also hold a reference on the session. | |
593 | */ | |
594 | static | |
595 | long lttng_metadata_cmd(int objd, unsigned int cmd, unsigned long arg) | |
596 | { | |
597 | switch (cmd) { | |
598 | case LTTNG_UST_STREAM: | |
599 | return -ENOSYS; //TODO | |
600 | //return lttng_abi_open_stream(objd); | |
601 | default: | |
602 | return -EINVAL; | |
603 | } | |
604 | } | |
605 | ||
606 | #if 0 | |
607 | /** | |
608 | * lttng_channel_poll - lttng stream addition/removal monitoring | |
609 | * | |
610 | * @file: the file | |
611 | * @wait: poll table | |
612 | */ | |
613 | unsigned int lttng_channel_poll(struct file *file, poll_table *wait) | |
614 | { | |
615 | struct ltt_channel *channel = file->private_data; | |
616 | unsigned int mask = 0; | |
617 | ||
618 | if (file->f_mode & FMODE_READ) { | |
619 | poll_wait_set_exclusive(wait); | |
620 | poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan), | |
621 | wait); | |
622 | ||
623 | if (channel->ops->is_disabled(channel->chan)) | |
624 | return POLLERR; | |
625 | if (channel->ops->is_finalized(channel->chan)) | |
626 | return POLLHUP; | |
627 | if (channel->ops->buffer_has_read_closed_stream(channel->chan)) | |
628 | return POLLIN | POLLRDNORM; | |
629 | return 0; | |
630 | } | |
631 | return mask; | |
632 | ||
633 | } | |
634 | #endif //0 | |
635 | ||
636 | static | |
637 | int lttng_channel_release(int objd) | |
638 | { | |
639 | struct ltt_channel *channel = objd_private(objd); | |
640 | ||
641 | if (channel) | |
642 | objd_unref(channel->session->objd); | |
643 | return 0; | |
644 | } | |
645 | ||
646 | static const struct objd_ops lttng_channel_ops = { | |
647 | .release = lttng_channel_release, | |
648 | //.poll = lttng_channel_poll, | |
649 | .cmd = lttng_channel_cmd, | |
650 | }; | |
651 | ||
652 | static const struct objd_ops lttng_metadata_ops = { | |
653 | .release = lttng_channel_release, | |
654 | .cmd = lttng_metadata_cmd, | |
655 | }; | |
656 | ||
657 | /** | |
658 | * lttng_event_cmd - lttng control through object descriptors | |
659 | * | |
660 | * @objd: the object descriptor | |
661 | * @cmd: the command | |
662 | * @arg: command arg | |
663 | * | |
664 | * This object descriptor implements lttng commands: | |
665 | * LTTNG_UST_CONTEXT | |
666 | * Prepend a context field to each record of this event | |
667 | * LTTNG_UST_ENABLE | |
668 | * Enable recording for this event (weak enable) | |
669 | * LTTNG_UST_DISABLE | |
670 | * Disable recording for this event (strong disable) | |
671 | */ | |
672 | static | |
673 | long lttng_event_cmd(int objd, unsigned int cmd, unsigned long arg) | |
674 | { | |
675 | struct ltt_event *event = objd_private(objd); | |
676 | ||
677 | switch (cmd) { | |
678 | case LTTNG_UST_CONTEXT: | |
679 | return lttng_abi_add_context(objd, | |
680 | (struct lttng_ust_context *) arg, | |
681 | &event->ctx, event->chan->session); | |
682 | case LTTNG_UST_ENABLE: | |
683 | return ltt_event_enable(event); | |
684 | case LTTNG_UST_DISABLE: | |
685 | return ltt_event_disable(event); | |
686 | default: | |
687 | return -EINVAL; | |
688 | } | |
689 | } | |
690 | ||
691 | static | |
692 | int lttng_event_release(int objd) | |
693 | { | |
694 | struct ltt_event *event = objd_private(objd); | |
695 | ||
696 | if (event) | |
697 | objd_unref(event->chan->objd); | |
698 | return 0; | |
699 | } | |
700 | ||
701 | /* TODO: filter control ioctl */ | |
702 | static const struct objd_ops lttng_event_ops = { | |
703 | .release = lttng_event_release, | |
704 | .cmd = lttng_event_cmd, | |
705 | }; | |
706 | ||
707 | void __attribute__((constructor)) lttng_ust_abi_init(void) | |
708 | { | |
5e96a467 | 709 | init_usterr(); |
f4681817 MD |
710 | /* TODO: initialize socket */ |
711 | } | |
712 | ||
713 | static | |
714 | void __attribute__((destructor)) lttng_ust_abi_exit(void) | |
715 | { | |
716 | /* TODO: teardown socket */ | |
717 | objd_table_destroy(); | |
718 | } |