Commit | Line | Data |
---|---|---|
4e3c1b9b MD |
1 | /* |
2 | * ltt-events.c | |
3 | * | |
4 | * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
5 | * | |
6 | * Holds LTTng per-session event registry. | |
7 | */ | |
8 | ||
9 | #include <linux/module.h> | |
c0e31d2e MD |
10 | #include <linux/list.h> |
11 | #include <linux/mutex.h> | |
12 | #include <linux/sched.h> | |
11b5a3c2 | 13 | #include <linux/slab.h> |
c099397a | 14 | #include <linux/jiffies.h> |
b13f3ebe | 15 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
4e3c1b9b | 16 | #include "ltt-events.h" |
c099397a | 17 | #include "ltt-tracer.h" |
4e3c1b9b MD |
18 | |
19 | static LIST_HEAD(sessions); | |
c0e31d2e | 20 | static LIST_HEAD(ltt_transport_list); |
4e3c1b9b MD |
21 | static DEFINE_MUTEX(sessions_mutex); |
22 | static struct kmem_cache *event_cache; | |
23 | ||
c099397a MD |
24 | static |
25 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
26 | struct ltt_channel *chan, | |
27 | struct ltt_event *event); | |
28 | static | |
29 | int _ltt_session_metadata_statedump(struct ltt_session *session); | |
30 | ||
31 | ||
32 | static | |
33 | void synchronize_trace(void) | |
abcca994 MD |
34 | { |
35 | synchronize_sched(); | |
36 | #ifdef CONFIG_PREEMPT_RT | |
37 | synchronize_rcu(); | |
38 | #endif | |
39 | } | |
40 | ||
baf20995 | 41 | struct ltt_session *ltt_session_create(void) |
4e3c1b9b MD |
42 | { |
43 | struct ltt_session *session; | |
44 | ||
45 | mutex_lock(&sessions_mutex); | |
f3d01b96 | 46 | session = kzalloc(sizeof(struct ltt_session), GFP_KERNEL); |
4e3c1b9b MD |
47 | if (!session) |
48 | return NULL; | |
4e3c1b9b | 49 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 50 | INIT_LIST_HEAD(&session->events); |
4e3c1b9b MD |
51 | list_add(&session->list, &sessions); |
52 | mutex_unlock(&sessions_mutex); | |
53 | return session; | |
4e3c1b9b MD |
54 | } |
55 | ||
11b5a3c2 | 56 | void ltt_session_destroy(struct ltt_session *session) |
4e3c1b9b MD |
57 | { |
58 | struct ltt_channel *chan, *tmpchan; | |
59 | struct ltt_event *event, *tmpevent; | |
dda6a249 | 60 | int ret; |
4e3c1b9b MD |
61 | |
62 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 63 | ACCESS_ONCE(session->active) = 0; |
dda6a249 MD |
64 | list_for_each_entry(event, &session->events, list) { |
65 | ret = _ltt_event_unregister(event); | |
66 | WARN_ON(ret); | |
67 | } | |
abcca994 | 68 | synchronize_trace(); /* Wait for in-flight events to complete */ |
4e3c1b9b MD |
69 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
70 | _ltt_event_destroy(event); | |
71 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) | |
72 | _ltt_channel_destroy(chan); | |
73 | list_del(&session->list); | |
74 | mutex_unlock(&sessions_mutex); | |
75 | kfree(session); | |
76 | } | |
77 | ||
c0e31d2e MD |
78 | int ltt_session_start(struct ltt_session *session) |
79 | { | |
80 | int ret = 0; | |
c099397a | 81 | struct ltt_channel *chan; |
c0e31d2e MD |
82 | |
83 | mutex_lock(&sessions_mutex); | |
84 | if (session->active) { | |
85 | ret = -EBUSY; | |
86 | goto end; | |
87 | } | |
c099397a MD |
88 | |
89 | /* | |
90 | * Snapshot the number of events per channel to know the type of header | |
91 | * we need to use. | |
92 | */ | |
93 | list_for_each_entry(chan, &session->chan, list) { | |
94 | if (chan->header_type) | |
95 | continue; /* don't change it if session stop/restart */ | |
96 | if (chan->free_event_id < 31) | |
97 | chan->header_type = 1; /* compact */ | |
98 | else | |
99 | chan->header_type = 2; /* large */ | |
100 | } | |
101 | ||
52fc2e1f | 102 | ACCESS_ONCE(session->active) = 1; |
c0e31d2e | 103 | synchronize_trace(); /* Wait for in-flight events to complete */ |
c099397a MD |
104 | ret = _ltt_session_metadata_statedump(session); |
105 | if (ret) { | |
106 | ACCESS_ONCE(session->active) = 0; | |
107 | synchronize_trace(); /* Wait for in-flight events to complete */ | |
108 | } | |
c0e31d2e MD |
109 | end: |
110 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 111 | return ret; |
c0e31d2e MD |
112 | } |
113 | ||
114 | int ltt_session_stop(struct ltt_session *session) | |
115 | { | |
116 | int ret = 0; | |
117 | ||
118 | mutex_lock(&sessions_mutex); | |
119 | if (!session->active) { | |
120 | ret = -EBUSY; | |
121 | goto end; | |
122 | } | |
52fc2e1f | 123 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
124 | synchronize_trace(); /* Wait for in-flight events to complete */ |
125 | end: | |
126 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 127 | return ret; |
c0e31d2e MD |
128 | } |
129 | ||
c535175e | 130 | static struct ltt_transport *ltt_transport_find(const char *name) |
f3d01b96 MD |
131 | { |
132 | struct ltt_transport *transport; | |
133 | ||
134 | list_for_each_entry(transport, <t_transport_list, node) { | |
135 | if (!strcmp(transport->name, name)) | |
136 | return transport; | |
137 | } | |
138 | return NULL; | |
139 | } | |
140 | ||
baf20995 | 141 | struct ltt_channel *ltt_channel_create(struct ltt_session *session, |
5dbbdb43 MD |
142 | const char *transport_name, |
143 | void *buf_addr, | |
4e3c1b9b MD |
144 | size_t subbuf_size, size_t num_subbuf, |
145 | unsigned int switch_timer_interval, | |
146 | unsigned int read_timer_interval) | |
147 | { | |
148 | struct ltt_channel *chan; | |
f3d01b96 | 149 | struct ltt_transport *transport; |
4e3c1b9b MD |
150 | |
151 | mutex_lock(&sessions_mutex); | |
f3d01b96 MD |
152 | if (session->active) { |
153 | printk(KERN_WARNING "LTTng refusing to add channel to active session\n"); | |
e5382b6d | 154 | goto active; /* Refuse to add channel to active session */ |
c0e31d2e | 155 | } |
f3d01b96 MD |
156 | transport = ltt_transport_find(transport_name); |
157 | if (!transport) { | |
158 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
159 | transport_name); | |
c0e31d2e | 160 | goto notransport; |
f3d01b96 | 161 | } |
f3d01b96 | 162 | chan = kzalloc(sizeof(struct ltt_channel), GFP_KERNEL); |
4e3c1b9b | 163 | if (!chan) |
c0e31d2e | 164 | goto nomem; |
4e3c1b9b | 165 | chan->session = session; |
653fe716 | 166 | init_waitqueue_head(&chan->notify_wait); |
11b5a3c2 MD |
167 | chan->chan = transport->ops.channel_create("[lttng]", session, buf_addr, |
168 | subbuf_size, num_subbuf, switch_timer_interval, | |
169 | read_timer_interval); | |
f3d01b96 MD |
170 | if (!chan->chan) |
171 | goto create_error; | |
c099397a | 172 | chan->id = session->free_chan_id++; |
11b5a3c2 | 173 | chan->ops = &transport->ops; |
4e3c1b9b MD |
174 | list_add(&chan->list, &session->chan); |
175 | mutex_unlock(&sessions_mutex); | |
176 | return chan; | |
177 | ||
f3d01b96 MD |
178 | create_error: |
179 | kfree(chan); | |
c0e31d2e MD |
180 | nomem: |
181 | notransport: | |
e5382b6d | 182 | active: |
4e3c1b9b MD |
183 | mutex_unlock(&sessions_mutex); |
184 | return NULL; | |
185 | } | |
186 | ||
187 | /* | |
188 | * Only used internally at session destruction. | |
189 | */ | |
11b5a3c2 | 190 | void _ltt_channel_destroy(struct ltt_channel *chan) |
4e3c1b9b | 191 | { |
11b5a3c2 | 192 | chan->ops->channel_destroy(chan->chan); |
4e3c1b9b MD |
193 | list_del(&chan->list); |
194 | kfree(chan); | |
195 | } | |
196 | ||
e5382b6d MD |
197 | /* |
198 | * Supports event creation while tracing session is active. | |
199 | */ | |
4e3c1b9b | 200 | struct ltt_event *ltt_event_create(struct ltt_channel *chan, char *name, |
baf20995 | 201 | enum instrum_type itype, |
85a9ca7f MD |
202 | const struct lttng_event_desc *event_desc, |
203 | void *filter) | |
4e3c1b9b MD |
204 | { |
205 | struct ltt_event *event; | |
3d084699 | 206 | int ret; |
4e3c1b9b MD |
207 | |
208 | mutex_lock(&sessions_mutex); | |
e5382b6d MD |
209 | if (chan->free_event_id == -1UL) |
210 | goto full; | |
4e3c1b9b | 211 | /* |
dda6a249 MD |
212 | * This is O(n^2) (for each event, the loop is called at event |
213 | * creation). Might require a hash if we have lots of events. | |
4e3c1b9b MD |
214 | */ |
215 | list_for_each_entry(event, &chan->session->events, list) | |
85a9ca7f | 216 | if (!strcmp(event->desc->name, name)) |
4e3c1b9b | 217 | goto exist; |
11b5a3c2 | 218 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
4e3c1b9b MD |
219 | if (!event) |
220 | goto cache_error; | |
4e3c1b9b | 221 | event->chan = chan; |
85a9ca7f | 222 | event->desc = event_desc; |
4e3c1b9b | 223 | event->filter = filter; |
e5382b6d | 224 | event->id = chan->free_event_id++; |
baf20995 | 225 | event->itype = itype; |
e5382b6d MD |
226 | /* Populate ltt_event structure before tracepoint registration. */ |
227 | smp_wmb(); | |
baf20995 MD |
228 | switch (itype) { |
229 | case INSTRUM_TRACEPOINTS: | |
85a9ca7f MD |
230 | ret = tracepoint_probe_register(name, event_desc->probe_callback, |
231 | event); | |
11b5a3c2 MD |
232 | if (ret) |
233 | goto register_error; | |
baf20995 MD |
234 | break; |
235 | default: | |
236 | WARN_ON_ONCE(1); | |
237 | } | |
c099397a MD |
238 | ret = _ltt_event_metadata_statedump(chan->session, chan, event); |
239 | if (ret) | |
240 | goto statedump_error; | |
dda6a249 | 241 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 242 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
243 | return event; |
244 | ||
c099397a MD |
245 | statedump_error: |
246 | WARN_ON_ONCE(tracepoint_probe_unregister(name, event_desc->probe_callback, | |
247 | event)); | |
11b5a3c2 | 248 | register_error: |
11b5a3c2 | 249 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
250 | cache_error: |
251 | exist: | |
e5382b6d | 252 | full: |
4e3c1b9b MD |
253 | mutex_unlock(&sessions_mutex); |
254 | return NULL; | |
255 | } | |
256 | ||
257 | /* | |
258 | * Only used internally at session destruction. | |
259 | */ | |
dda6a249 | 260 | int _ltt_event_unregister(struct ltt_event *event) |
4e3c1b9b | 261 | { |
11b5a3c2 MD |
262 | int ret = -EINVAL; |
263 | ||
baf20995 MD |
264 | switch (event->itype) { |
265 | case INSTRUM_TRACEPOINTS: | |
85a9ca7f MD |
266 | ret = tracepoint_probe_unregister(event->desc->name, |
267 | event->desc->probe_callback, | |
11b5a3c2 MD |
268 | event); |
269 | if (ret) | |
270 | return ret; | |
baf20995 MD |
271 | break; |
272 | default: | |
273 | WARN_ON_ONCE(1); | |
274 | } | |
dda6a249 MD |
275 | return ret; |
276 | } | |
277 | ||
278 | /* | |
279 | * Only used internally at session destruction. | |
280 | */ | |
281 | void _ltt_event_destroy(struct ltt_event *event) | |
282 | { | |
85a9ca7f | 283 | ltt_event_put(event->desc); |
dda6a249 | 284 | list_del(&event->list); |
11b5a3c2 | 285 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
286 | } |
287 | ||
c099397a MD |
288 | int lttng_metadata_printf(struct ltt_session *session, |
289 | const char *fmt, ...) | |
290 | { | |
291 | struct lib_ring_buffer_ctx ctx; | |
292 | struct ltt_channel *chan = session->metadata; | |
293 | char *str; | |
294 | int ret = 0, waitret; | |
295 | size_t len; | |
296 | va_list ap; | |
297 | ||
298 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
299 | ||
300 | va_start(ap, fmt); | |
301 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
302 | va_end(ap); | |
303 | if (!str) | |
304 | return -ENOMEM; | |
305 | ||
306 | len = strlen(str) + 1; | |
307 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, len, sizeof(char), -1); | |
308 | /* | |
309 | * We don't care about metadata buffer's records lost count, because we | |
310 | * always retry here. Report error if we need to bail out after timeout | |
311 | * or being interrupted. | |
312 | */ | |
313 | waitret = wait_event_interruptible_timeout(*chan->ops->get_reader_wait_queue(chan), | |
314 | ({ | |
315 | ret = chan->ops->event_reserve(&ctx); | |
316 | ret != -ENOBUFS || !ret; | |
317 | }), | |
318 | msecs_to_jiffies(LTTNG_METADATA_TIMEOUT_MSEC)); | |
319 | if (waitret || ret) { | |
320 | printk(KERN_WARNING "LTTng: Failure to write metadata to buffers (%s)\n", | |
321 | waitret == -ERESTARTSYS ? "interrupted" : | |
322 | (ret == -ENOBUFS ? "timeout" : "I/O error")); | |
323 | if (waitret == -ERESTARTSYS) | |
324 | ret = waitret; | |
325 | goto end; | |
326 | } | |
327 | chan->ops->event_write(&ctx, str, len); | |
328 | chan->ops->event_commit(&ctx); | |
329 | end: | |
330 | kfree(str); | |
331 | return ret; | |
332 | } | |
333 | ||
334 | static | |
335 | int _ltt_fields_metadata_statedump(struct ltt_session *session, | |
336 | struct ltt_event *event) | |
337 | { | |
338 | const struct lttng_event_desc *desc = event->desc; | |
339 | int ret = 0; | |
340 | int i; | |
341 | ||
342 | for (i = 0; i < desc->nr_fields; i++) { | |
343 | const struct lttng_event_field *field = &desc->fields[i]; | |
344 | ||
345 | switch (field->type.atype) { | |
346 | case atype_integer: | |
347 | ret = lttng_metadata_printf(session, | |
348 | " integer { size = %u; align = %u; signed = %u;%s } %s;\n", | |
349 | field->type.u.basic.integer.size, | |
350 | field->type.u.basic.integer.alignment, | |
351 | field->type.u.basic.integer.signedness, | |
352 | #ifdef __BIG_ENDIAN | |
353 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", | |
354 | #else | |
355 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
356 | #endif | |
357 | field->name); | |
358 | break; | |
359 | case atype_enum: | |
360 | ret = lttng_metadata_printf(session, | |
361 | " %s %s;\n", | |
362 | field->type.u.basic.enumeration.name, | |
363 | field->name); | |
364 | break; | |
365 | case atype_array: | |
8fa75f34 MD |
366 | { |
367 | const struct lttng_basic_type *elem_type; | |
368 | ||
369 | elem_type = &field->type.u.array.elem_type; | |
370 | ret = lttng_metadata_printf(session, | |
371 | " integer { size = %u; align = %u; signed = %u;%s } %s[%u];\n", | |
372 | elem_type->u.basic.integer.size, | |
373 | elem_type->u.basic.integer.alignment, | |
374 | elem_type->u.basic.integer.signedness, | |
375 | #ifdef __BIG_ENDIAN | |
376 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", | |
377 | #else | |
378 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
379 | #endif | |
380 | field->name, field->type.u.array.length); | |
c099397a | 381 | break; |
8fa75f34 | 382 | } |
c099397a | 383 | case atype_sequence: |
8fa75f34 MD |
384 | { |
385 | const struct lttng_basic_type *elem_type; | |
386 | const struct lttng_basic_type *length_type; | |
387 | ||
388 | elem_type = &field->type.u.sequence.elem_type; | |
389 | length_type = &field->type.u.sequence.length_type; | |
390 | ret = lttng_metadata_printf(session, | |
391 | " integer { size = %u; align = %u; signed = %u;%s } %s[ integer { size = %u; align = %u; signed = %u;%s } ];\n", | |
392 | elem_type->u.basic.integer.size, | |
393 | elem_type->u.basic.integer.alignment, | |
394 | elem_type->u.basic.integer.signedness, | |
395 | #ifdef __BIG_ENDIAN | |
396 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", | |
397 | #else | |
398 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", | |
399 | #endif | |
400 | field->name, | |
401 | length_type->u.basic.integer.size, | |
402 | length_type->u.basic.integer.alignment, | |
403 | length_type->u.basic.integer.signedness, | |
404 | #ifdef __BIG_ENDIAN | |
405 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", | |
406 | #else | |
407 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "" | |
408 | #endif | |
409 | ); | |
c099397a | 410 | break; |
8fa75f34 | 411 | } |
c099397a MD |
412 | |
413 | case atype_string: | |
414 | ret = lttng_metadata_printf(session, | |
415 | " string%s %s;\n", | |
416 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? | |
417 | " { encoding = ASCII; }" : "", | |
418 | field->name); | |
419 | break; | |
420 | default: | |
421 | WARN_ON_ONCE(1); | |
422 | return -EINVAL; | |
423 | } | |
424 | } | |
425 | return ret; | |
426 | } | |
427 | ||
428 | static | |
429 | int _ltt_event_metadata_statedump(struct ltt_session *session, | |
430 | struct ltt_channel *chan, | |
431 | struct ltt_event *event) | |
432 | { | |
433 | int ret = 0; | |
434 | ||
435 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
436 | return 0; | |
437 | if (chan == session->metadata) | |
438 | return 0; | |
439 | ||
440 | ret = lttng_metadata_printf(session, | |
441 | "event {\n" | |
442 | " name = %s;\n" | |
443 | " id = %u;\n" | |
444 | " stream_id = %u;\n" | |
445 | " event.fields := struct {\n", | |
446 | event->desc->name, | |
447 | event->id, | |
448 | event->chan->id); | |
449 | if (ret) | |
450 | goto end; | |
451 | ||
452 | ret = _ltt_fields_metadata_statedump(session, event); | |
453 | if (ret) | |
454 | goto end; | |
455 | ||
456 | /* | |
457 | * LTTng space reservation can only reserve multiples of the | |
458 | * byte size. | |
459 | */ | |
460 | ret = lttng_metadata_printf(session, | |
461 | " } aligned(%u);\n" | |
462 | "};\n", ltt_get_header_alignment()); | |
463 | if (ret) | |
464 | goto end; | |
465 | ||
466 | ||
467 | ||
468 | ||
469 | event->metadata_dumped = 1; | |
470 | end: | |
471 | return ret; | |
472 | ||
473 | } | |
474 | ||
475 | static | |
476 | int _ltt_channel_metadata_statedump(struct ltt_session *session, | |
477 | struct ltt_channel *chan) | |
478 | { | |
479 | int ret = 0; | |
480 | ||
481 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
482 | return 0; | |
483 | if (chan == session->metadata) | |
484 | return 0; | |
485 | ||
486 | WARN_ON_ONCE(!chan->header_type); | |
487 | ret = lttng_metadata_printf(session, | |
488 | "stream {\n" | |
489 | " id = %u;\n" | |
490 | " event.header := %s;\n", | |
491 | "};\n", | |
492 | chan->id, | |
493 | chan->header_type == 1 ? "struct event_header_compact" : | |
494 | "struct event_header_large"); | |
495 | if (ret) | |
496 | goto end; | |
497 | ||
498 | chan->metadata_dumped = 1; | |
499 | end: | |
500 | return ret; | |
501 | } | |
502 | ||
503 | /* | |
504 | * Output metadata into this session's metadata buffers. | |
505 | */ | |
506 | static | |
507 | int _ltt_session_metadata_statedump(struct ltt_session *session) | |
508 | { | |
509 | struct ltt_channel *chan; | |
510 | struct ltt_event *event; | |
511 | int ret = 0; | |
512 | ||
513 | if (!ACCESS_ONCE(session->active)) | |
514 | return 0; | |
515 | if (session->metadata_dumped) | |
516 | goto skip_session; | |
f40270ad | 517 | if (!session->metadata) { |
cd4bd11f | 518 | printk(KERN_WARNING "LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
f40270ad MD |
519 | return -EPERM; |
520 | } | |
c099397a MD |
521 | |
522 | skip_session: | |
523 | list_for_each_entry(chan, &session->chan, list) { | |
524 | ret = _ltt_channel_metadata_statedump(session, chan); | |
525 | if (ret) | |
526 | goto end; | |
527 | } | |
528 | ||
529 | list_for_each_entry(event, &session->events, list) { | |
530 | ret = _ltt_event_metadata_statedump(session, chan, event); | |
531 | if (ret) | |
532 | goto end; | |
533 | } | |
534 | session->metadata_dumped = 1; | |
535 | end: | |
536 | return ret; | |
537 | } | |
538 | ||
c0e31d2e MD |
539 | /** |
540 | * ltt_transport_register - LTT transport registration | |
541 | * @transport: transport structure | |
542 | * | |
543 | * Registers a transport which can be used as output to extract the data out of | |
544 | * LTTng. The module calling this registration function must ensure that no | |
545 | * trap-inducing code will be executed by the transport functions. E.g. | |
546 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
547 | * is made visible to the transport function. This registration acts as a | |
548 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
549 | * after its registration must it synchronize the TLBs. | |
550 | */ | |
551 | void ltt_transport_register(struct ltt_transport *transport) | |
552 | { | |
553 | /* | |
554 | * Make sure no page fault can be triggered by the module about to be | |
555 | * registered. We deal with this here so we don't have to call | |
556 | * vmalloc_sync_all() in each module's init. | |
557 | */ | |
6d2a620c | 558 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
559 | |
560 | mutex_lock(&sessions_mutex); | |
561 | list_add_tail(&transport->node, <t_transport_list); | |
562 | mutex_unlock(&sessions_mutex); | |
563 | } | |
564 | EXPORT_SYMBOL_GPL(ltt_transport_register); | |
565 | ||
566 | /** | |
567 | * ltt_transport_unregister - LTT transport unregistration | |
568 | * @transport: transport structure | |
569 | */ | |
570 | void ltt_transport_unregister(struct ltt_transport *transport) | |
571 | { | |
572 | mutex_lock(&sessions_mutex); | |
573 | list_del(&transport->node); | |
574 | mutex_unlock(&sessions_mutex); | |
575 | } | |
576 | EXPORT_SYMBOL_GPL(ltt_transport_unregister); | |
577 | ||
4e3c1b9b MD |
578 | static int __init ltt_events_init(void) |
579 | { | |
1c25284c MD |
580 | int ret; |
581 | ||
11b5a3c2 MD |
582 | event_cache = KMEM_CACHE(ltt_event, 0); |
583 | if (!event_cache) | |
4e3c1b9b | 584 | return -ENOMEM; |
02119ee5 MD |
585 | ret = ltt_debugfs_abi_init(); |
586 | if (ret) | |
587 | goto error_abi; | |
4e3c1b9b | 588 | return 0; |
02119ee5 | 589 | error_abi: |
1c25284c MD |
590 | kmem_cache_destroy(event_cache); |
591 | return ret; | |
4e3c1b9b MD |
592 | } |
593 | ||
11b5a3c2 MD |
594 | module_init(ltt_events_init); |
595 | ||
4e3c1b9b MD |
596 | static void __exit ltt_events_exit(void) |
597 | { | |
92e94819 MD |
598 | struct ltt_session *session, *tmpsession; |
599 | ||
1c25284c | 600 | ltt_debugfs_abi_exit(); |
92e94819 MD |
601 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
602 | ltt_session_destroy(session); | |
11b5a3c2 | 603 | kmem_cache_destroy(event_cache); |
4e3c1b9b | 604 | } |
92e94819 | 605 | |
11b5a3c2 MD |
606 | module_exit(ltt_events_exit); |
607 | ||
92e94819 MD |
608 | MODULE_LICENSE("GPL and additional rights"); |
609 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
610 | MODULE_DESCRIPTION("LTTng Events"); |