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Fix: Remove 'type' argument from access_ok() function (v5.0)
[lttng-modules.git] / lttng-events.c
1 /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
2 *
3 * lttng-events.c
4 *
5 * Holds LTTng per-session event registry.
6 *
7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 */
9
10 /*
11 * This page_alloc.h wrapper needs to be included before gfpflags.h because it
12 * overrides a function with a define.
13 */
14 #include "wrapper/page_alloc.h"
15
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/jiffies.h>
21 #include <linux/utsname.h>
22 #include <linux/err.h>
23 #include <linux/seq_file.h>
24 #include <linux/file.h>
25 #include <linux/anon_inodes.h>
26 #include <wrapper/file.h>
27 #include <linux/jhash.h>
28 #include <linux/uaccess.h>
29 #include <linux/vmalloc.h>
30 #include <linux/uuid.h>
31
32 #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_all() */
33 #include <wrapper/random.h>
34 #include <wrapper/tracepoint.h>
35 #include <wrapper/list.h>
36 #include <wrapper/types.h>
37 #include <lttng-kernel-version.h>
38 #include <lttng-events.h>
39 #include <lttng-tracer.h>
40 #include <lttng-abi-old.h>
41 #include <lttng-endian.h>
42 #include <lttng-string-utils.h>
43 #include <wrapper/ringbuffer/backend.h>
44 #include <wrapper/ringbuffer/frontend.h>
45
46 #define METADATA_CACHE_DEFAULT_SIZE 4096
47
48 static LIST_HEAD(sessions);
49 static LIST_HEAD(lttng_transport_list);
50 /*
51 * Protect the sessions and metadata caches.
52 */
53 static DEFINE_MUTEX(sessions_mutex);
54 static struct kmem_cache *event_cache;
55
56 static void lttng_session_lazy_sync_enablers(struct lttng_session *session);
57 static void lttng_session_sync_enablers(struct lttng_session *session);
58 static void lttng_enabler_destroy(struct lttng_enabler *enabler);
59
60 static void _lttng_event_destroy(struct lttng_event *event);
61 static void _lttng_channel_destroy(struct lttng_channel *chan);
62 static int _lttng_event_unregister(struct lttng_event *event);
63 static
64 int _lttng_event_metadata_statedump(struct lttng_session *session,
65 struct lttng_channel *chan,
66 struct lttng_event *event);
67 static
68 int _lttng_session_metadata_statedump(struct lttng_session *session);
69 static
70 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
71 static
72 int _lttng_field_statedump(struct lttng_session *session,
73 const struct lttng_event_field *field,
74 size_t nesting);
75
76 void synchronize_trace(void)
77 {
78 synchronize_sched();
79 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
80 #ifdef CONFIG_PREEMPT_RT_FULL
81 synchronize_rcu();
82 #endif
83 #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
84 #ifdef CONFIG_PREEMPT_RT
85 synchronize_rcu();
86 #endif
87 #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
88 }
89
90 void lttng_lock_sessions(void)
91 {
92 mutex_lock(&sessions_mutex);
93 }
94
95 void lttng_unlock_sessions(void)
96 {
97 mutex_unlock(&sessions_mutex);
98 }
99
100 /*
101 * Called with sessions lock held.
102 */
103 int lttng_session_active(void)
104 {
105 struct lttng_session *iter;
106
107 list_for_each_entry(iter, &sessions, list) {
108 if (iter->active)
109 return 1;
110 }
111 return 0;
112 }
113
114 struct lttng_session *lttng_session_create(void)
115 {
116 struct lttng_session *session;
117 struct lttng_metadata_cache *metadata_cache;
118 int i;
119
120 mutex_lock(&sessions_mutex);
121 session = lttng_kvzalloc(sizeof(struct lttng_session), GFP_KERNEL);
122 if (!session)
123 goto err;
124 INIT_LIST_HEAD(&session->chan);
125 INIT_LIST_HEAD(&session->events);
126 uuid_le_gen(&session->uuid);
127
128 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
129 GFP_KERNEL);
130 if (!metadata_cache)
131 goto err_free_session;
132 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
133 if (!metadata_cache->data)
134 goto err_free_cache;
135 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
136 kref_init(&metadata_cache->refcount);
137 mutex_init(&metadata_cache->lock);
138 session->metadata_cache = metadata_cache;
139 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
140 memcpy(&metadata_cache->uuid, &session->uuid,
141 sizeof(metadata_cache->uuid));
142 INIT_LIST_HEAD(&session->enablers_head);
143 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
144 INIT_HLIST_HEAD(&session->events_ht.table[i]);
145 list_add(&session->list, &sessions);
146 mutex_unlock(&sessions_mutex);
147 return session;
148
149 err_free_cache:
150 kfree(metadata_cache);
151 err_free_session:
152 lttng_kvfree(session);
153 err:
154 mutex_unlock(&sessions_mutex);
155 return NULL;
156 }
157
158 void metadata_cache_destroy(struct kref *kref)
159 {
160 struct lttng_metadata_cache *cache =
161 container_of(kref, struct lttng_metadata_cache, refcount);
162 vfree(cache->data);
163 kfree(cache);
164 }
165
166 void lttng_session_destroy(struct lttng_session *session)
167 {
168 struct lttng_channel *chan, *tmpchan;
169 struct lttng_event *event, *tmpevent;
170 struct lttng_metadata_stream *metadata_stream;
171 struct lttng_enabler *enabler, *tmpenabler;
172 int ret;
173
174 mutex_lock(&sessions_mutex);
175 WRITE_ONCE(session->active, 0);
176 list_for_each_entry(chan, &session->chan, list) {
177 ret = lttng_syscalls_unregister(chan);
178 WARN_ON(ret);
179 }
180 list_for_each_entry(event, &session->events, list) {
181 ret = _lttng_event_unregister(event);
182 WARN_ON(ret);
183 }
184 synchronize_trace(); /* Wait for in-flight events to complete */
185 list_for_each_entry_safe(enabler, tmpenabler,
186 &session->enablers_head, node)
187 lttng_enabler_destroy(enabler);
188 list_for_each_entry_safe(event, tmpevent, &session->events, list)
189 _lttng_event_destroy(event);
190 list_for_each_entry_safe(chan, tmpchan, &session->chan, list) {
191 BUG_ON(chan->channel_type == METADATA_CHANNEL);
192 _lttng_channel_destroy(chan);
193 }
194 list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
195 _lttng_metadata_channel_hangup(metadata_stream);
196 if (session->pid_tracker)
197 lttng_pid_tracker_destroy(session->pid_tracker);
198 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
199 list_del(&session->list);
200 mutex_unlock(&sessions_mutex);
201 lttng_kvfree(session);
202 }
203
204 int lttng_session_statedump(struct lttng_session *session)
205 {
206 int ret;
207
208 mutex_lock(&sessions_mutex);
209 ret = lttng_statedump_start(session);
210 mutex_unlock(&sessions_mutex);
211 return ret;
212 }
213
214 int lttng_session_enable(struct lttng_session *session)
215 {
216 int ret = 0;
217 struct lttng_channel *chan;
218
219 mutex_lock(&sessions_mutex);
220 if (session->active) {
221 ret = -EBUSY;
222 goto end;
223 }
224
225 /* Set transient enabler state to "enabled" */
226 session->tstate = 1;
227
228 /* We need to sync enablers with session before activation. */
229 lttng_session_sync_enablers(session);
230
231 /*
232 * Snapshot the number of events per channel to know the type of header
233 * we need to use.
234 */
235 list_for_each_entry(chan, &session->chan, list) {
236 if (chan->header_type)
237 continue; /* don't change it if session stop/restart */
238 if (chan->free_event_id < 31)
239 chan->header_type = 1; /* compact */
240 else
241 chan->header_type = 2; /* large */
242 }
243
244 /* Clear each stream's quiescent state. */
245 list_for_each_entry(chan, &session->chan, list) {
246 if (chan->channel_type != METADATA_CHANNEL)
247 lib_ring_buffer_clear_quiescent_channel(chan->chan);
248 }
249
250 WRITE_ONCE(session->active, 1);
251 WRITE_ONCE(session->been_active, 1);
252 ret = _lttng_session_metadata_statedump(session);
253 if (ret) {
254 WRITE_ONCE(session->active, 0);
255 goto end;
256 }
257 ret = lttng_statedump_start(session);
258 if (ret)
259 WRITE_ONCE(session->active, 0);
260 end:
261 mutex_unlock(&sessions_mutex);
262 return ret;
263 }
264
265 int lttng_session_disable(struct lttng_session *session)
266 {
267 int ret = 0;
268 struct lttng_channel *chan;
269
270 mutex_lock(&sessions_mutex);
271 if (!session->active) {
272 ret = -EBUSY;
273 goto end;
274 }
275 WRITE_ONCE(session->active, 0);
276
277 /* Set transient enabler state to "disabled" */
278 session->tstate = 0;
279 lttng_session_sync_enablers(session);
280
281 /* Set each stream's quiescent state. */
282 list_for_each_entry(chan, &session->chan, list) {
283 if (chan->channel_type != METADATA_CHANNEL)
284 lib_ring_buffer_set_quiescent_channel(chan->chan);
285 }
286 end:
287 mutex_unlock(&sessions_mutex);
288 return ret;
289 }
290
291 int lttng_session_metadata_regenerate(struct lttng_session *session)
292 {
293 int ret = 0;
294 struct lttng_channel *chan;
295 struct lttng_event *event;
296 struct lttng_metadata_cache *cache = session->metadata_cache;
297 struct lttng_metadata_stream *stream;
298
299 mutex_lock(&sessions_mutex);
300 if (!session->active) {
301 ret = -EBUSY;
302 goto end;
303 }
304
305 mutex_lock(&cache->lock);
306 memset(cache->data, 0, cache->cache_alloc);
307 cache->metadata_written = 0;
308 cache->version++;
309 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) {
310 stream->metadata_out = 0;
311 stream->metadata_in = 0;
312 }
313 mutex_unlock(&cache->lock);
314
315 session->metadata_dumped = 0;
316 list_for_each_entry(chan, &session->chan, list) {
317 chan->metadata_dumped = 0;
318 }
319
320 list_for_each_entry(event, &session->events, list) {
321 event->metadata_dumped = 0;
322 }
323
324 ret = _lttng_session_metadata_statedump(session);
325
326 end:
327 mutex_unlock(&sessions_mutex);
328 return ret;
329 }
330
331 int lttng_channel_enable(struct lttng_channel *channel)
332 {
333 int ret = 0;
334
335 mutex_lock(&sessions_mutex);
336 if (channel->channel_type == METADATA_CHANNEL) {
337 ret = -EPERM;
338 goto end;
339 }
340 if (channel->enabled) {
341 ret = -EEXIST;
342 goto end;
343 }
344 /* Set transient enabler state to "enabled" */
345 channel->tstate = 1;
346 lttng_session_sync_enablers(channel->session);
347 /* Set atomically the state to "enabled" */
348 WRITE_ONCE(channel->enabled, 1);
349 end:
350 mutex_unlock(&sessions_mutex);
351 return ret;
352 }
353
354 int lttng_channel_disable(struct lttng_channel *channel)
355 {
356 int ret = 0;
357
358 mutex_lock(&sessions_mutex);
359 if (channel->channel_type == METADATA_CHANNEL) {
360 ret = -EPERM;
361 goto end;
362 }
363 if (!channel->enabled) {
364 ret = -EEXIST;
365 goto end;
366 }
367 /* Set atomically the state to "disabled" */
368 WRITE_ONCE(channel->enabled, 0);
369 /* Set transient enabler state to "enabled" */
370 channel->tstate = 0;
371 lttng_session_sync_enablers(channel->session);
372 end:
373 mutex_unlock(&sessions_mutex);
374 return ret;
375 }
376
377 int lttng_event_enable(struct lttng_event *event)
378 {
379 int ret = 0;
380
381 mutex_lock(&sessions_mutex);
382 if (event->chan->channel_type == METADATA_CHANNEL) {
383 ret = -EPERM;
384 goto end;
385 }
386 if (event->enabled) {
387 ret = -EEXIST;
388 goto end;
389 }
390 switch (event->instrumentation) {
391 case LTTNG_KERNEL_TRACEPOINT:
392 case LTTNG_KERNEL_SYSCALL:
393 ret = -EINVAL;
394 break;
395 case LTTNG_KERNEL_KPROBE:
396 case LTTNG_KERNEL_FUNCTION:
397 case LTTNG_KERNEL_UPROBE:
398 case LTTNG_KERNEL_NOOP:
399 WRITE_ONCE(event->enabled, 1);
400 break;
401 case LTTNG_KERNEL_KRETPROBE:
402 ret = lttng_kretprobes_event_enable_state(event, 1);
403 break;
404 default:
405 WARN_ON_ONCE(1);
406 ret = -EINVAL;
407 }
408 end:
409 mutex_unlock(&sessions_mutex);
410 return ret;
411 }
412
413 int lttng_event_disable(struct lttng_event *event)
414 {
415 int ret = 0;
416
417 mutex_lock(&sessions_mutex);
418 if (event->chan->channel_type == METADATA_CHANNEL) {
419 ret = -EPERM;
420 goto end;
421 }
422 if (!event->enabled) {
423 ret = -EEXIST;
424 goto end;
425 }
426 switch (event->instrumentation) {
427 case LTTNG_KERNEL_TRACEPOINT:
428 case LTTNG_KERNEL_SYSCALL:
429 ret = -EINVAL;
430 break;
431 case LTTNG_KERNEL_KPROBE:
432 case LTTNG_KERNEL_FUNCTION:
433 case LTTNG_KERNEL_UPROBE:
434 case LTTNG_KERNEL_NOOP:
435 WRITE_ONCE(event->enabled, 0);
436 break;
437 case LTTNG_KERNEL_KRETPROBE:
438 ret = lttng_kretprobes_event_enable_state(event, 0);
439 break;
440 default:
441 WARN_ON_ONCE(1);
442 ret = -EINVAL;
443 }
444 end:
445 mutex_unlock(&sessions_mutex);
446 return ret;
447 }
448
449 static struct lttng_transport *lttng_transport_find(const char *name)
450 {
451 struct lttng_transport *transport;
452
453 list_for_each_entry(transport, &lttng_transport_list, node) {
454 if (!strcmp(transport->name, name))
455 return transport;
456 }
457 return NULL;
458 }
459
460 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
461 const char *transport_name,
462 void *buf_addr,
463 size_t subbuf_size, size_t num_subbuf,
464 unsigned int switch_timer_interval,
465 unsigned int read_timer_interval,
466 enum channel_type channel_type)
467 {
468 struct lttng_channel *chan;
469 struct lttng_transport *transport = NULL;
470
471 mutex_lock(&sessions_mutex);
472 if (session->been_active && channel_type != METADATA_CHANNEL)
473 goto active; /* Refuse to add channel to active session */
474 transport = lttng_transport_find(transport_name);
475 if (!transport) {
476 printk(KERN_WARNING "LTTng transport %s not found\n",
477 transport_name);
478 goto notransport;
479 }
480 if (!try_module_get(transport->owner)) {
481 printk(KERN_WARNING "LTT : Can't lock transport module.\n");
482 goto notransport;
483 }
484 chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL);
485 if (!chan)
486 goto nomem;
487 chan->session = session;
488 chan->id = session->free_chan_id++;
489 chan->ops = &transport->ops;
490 /*
491 * Note: the channel creation op already writes into the packet
492 * headers. Therefore the "chan" information used as input
493 * should be already accessible.
494 */
495 chan->chan = transport->ops.channel_create(transport_name,
496 chan, buf_addr, subbuf_size, num_subbuf,
497 switch_timer_interval, read_timer_interval);
498 if (!chan->chan)
499 goto create_error;
500 chan->tstate = 1;
501 chan->enabled = 1;
502 chan->transport = transport;
503 chan->channel_type = channel_type;
504 list_add(&chan->list, &session->chan);
505 mutex_unlock(&sessions_mutex);
506 return chan;
507
508 create_error:
509 kfree(chan);
510 nomem:
511 if (transport)
512 module_put(transport->owner);
513 notransport:
514 active:
515 mutex_unlock(&sessions_mutex);
516 return NULL;
517 }
518
519 /*
520 * Only used internally at session destruction for per-cpu channels, and
521 * when metadata channel is released.
522 * Needs to be called with sessions mutex held.
523 */
524 static
525 void _lttng_channel_destroy(struct lttng_channel *chan)
526 {
527 chan->ops->channel_destroy(chan->chan);
528 module_put(chan->transport->owner);
529 list_del(&chan->list);
530 lttng_destroy_context(chan->ctx);
531 kfree(chan);
532 }
533
534 void lttng_metadata_channel_destroy(struct lttng_channel *chan)
535 {
536 BUG_ON(chan->channel_type != METADATA_CHANNEL);
537
538 /* Protect the metadata cache with the sessions_mutex. */
539 mutex_lock(&sessions_mutex);
540 _lttng_channel_destroy(chan);
541 mutex_unlock(&sessions_mutex);
542 }
543 EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
544
545 static
546 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
547 {
548 stream->finalized = 1;
549 wake_up_interruptible(&stream->read_wait);
550 }
551
552 /*
553 * Supports event creation while tracing session is active.
554 * Needs to be called with sessions mutex held.
555 */
556 struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
557 struct lttng_kernel_event *event_param,
558 void *filter,
559 const struct lttng_event_desc *event_desc,
560 enum lttng_kernel_instrumentation itype)
561 {
562 struct lttng_session *session = chan->session;
563 struct lttng_event *event;
564 const char *event_name;
565 struct hlist_head *head;
566 size_t name_len;
567 uint32_t hash;
568 int ret;
569
570 if (chan->free_event_id == -1U) {
571 ret = -EMFILE;
572 goto full;
573 }
574
575 switch (itype) {
576 case LTTNG_KERNEL_TRACEPOINT:
577 event_name = event_desc->name;
578 break;
579 case LTTNG_KERNEL_KPROBE:
580 case LTTNG_KERNEL_UPROBE:
581 case LTTNG_KERNEL_KRETPROBE:
582 case LTTNG_KERNEL_FUNCTION:
583 case LTTNG_KERNEL_NOOP:
584 case LTTNG_KERNEL_SYSCALL:
585 event_name = event_param->name;
586 break;
587 default:
588 WARN_ON_ONCE(1);
589 ret = -EINVAL;
590 goto type_error;
591 }
592 name_len = strlen(event_name);
593 hash = jhash(event_name, name_len, 0);
594 head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
595 lttng_hlist_for_each_entry(event, head, hlist) {
596 WARN_ON_ONCE(!event->desc);
597 if (!strncmp(event->desc->name, event_name,
598 LTTNG_KERNEL_SYM_NAME_LEN - 1)
599 && chan == event->chan) {
600 ret = -EEXIST;
601 goto exist;
602 }
603 }
604
605 event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
606 if (!event) {
607 ret = -ENOMEM;
608 goto cache_error;
609 }
610 event->chan = chan;
611 event->filter = filter;
612 event->id = chan->free_event_id++;
613 event->instrumentation = itype;
614 event->evtype = LTTNG_TYPE_EVENT;
615 INIT_LIST_HEAD(&event->bytecode_runtime_head);
616 INIT_LIST_HEAD(&event->enablers_ref_head);
617
618 switch (itype) {
619 case LTTNG_KERNEL_TRACEPOINT:
620 /* Event will be enabled by enabler sync. */
621 event->enabled = 0;
622 event->registered = 0;
623 event->desc = lttng_event_get(event_name);
624 if (!event->desc) {
625 ret = -ENOENT;
626 goto register_error;
627 }
628 /* Populate lttng_event structure before event registration. */
629 smp_wmb();
630 break;
631 case LTTNG_KERNEL_KPROBE:
632 /*
633 * Needs to be explicitly enabled after creation, since
634 * we may want to apply filters.
635 */
636 event->enabled = 0;
637 event->registered = 1;
638 /*
639 * Populate lttng_event structure before event
640 * registration.
641 */
642 smp_wmb();
643 ret = lttng_kprobes_register(event_name,
644 event_param->u.kprobe.symbol_name,
645 event_param->u.kprobe.offset,
646 event_param->u.kprobe.addr,
647 event);
648 if (ret) {
649 ret = -EINVAL;
650 goto register_error;
651 }
652 ret = try_module_get(event->desc->owner);
653 WARN_ON_ONCE(!ret);
654 break;
655 case LTTNG_KERNEL_KRETPROBE:
656 {
657 struct lttng_event *event_return;
658
659 /* kretprobe defines 2 events */
660 /*
661 * Needs to be explicitly enabled after creation, since
662 * we may want to apply filters.
663 */
664 event->enabled = 0;
665 event->registered = 1;
666 event_return =
667 kmem_cache_zalloc(event_cache, GFP_KERNEL);
668 if (!event_return) {
669 ret = -ENOMEM;
670 goto register_error;
671 }
672 event_return->chan = chan;
673 event_return->filter = filter;
674 event_return->id = chan->free_event_id++;
675 event_return->enabled = 0;
676 event_return->registered = 1;
677 event_return->instrumentation = itype;
678 /*
679 * Populate lttng_event structure before kretprobe registration.
680 */
681 smp_wmb();
682 ret = lttng_kretprobes_register(event_name,
683 event_param->u.kretprobe.symbol_name,
684 event_param->u.kretprobe.offset,
685 event_param->u.kretprobe.addr,
686 event, event_return);
687 if (ret) {
688 kmem_cache_free(event_cache, event_return);
689 ret = -EINVAL;
690 goto register_error;
691 }
692 /* Take 2 refs on the module: one per event. */
693 ret = try_module_get(event->desc->owner);
694 WARN_ON_ONCE(!ret);
695 ret = try_module_get(event->desc->owner);
696 WARN_ON_ONCE(!ret);
697 ret = _lttng_event_metadata_statedump(chan->session, chan,
698 event_return);
699 WARN_ON_ONCE(ret > 0);
700 if (ret) {
701 kmem_cache_free(event_cache, event_return);
702 module_put(event->desc->owner);
703 module_put(event->desc->owner);
704 goto statedump_error;
705 }
706 list_add(&event_return->list, &chan->session->events);
707 break;
708 }
709 case LTTNG_KERNEL_FUNCTION:
710 /*
711 * Needs to be explicitly enabled after creation, since
712 * we may want to apply filters.
713 */
714 event->enabled = 0;
715 event->registered = 1;
716 /*
717 * Populate lttng_event structure before event
718 * registration.
719 */
720 smp_wmb();
721 ret = lttng_ftrace_register(event_name,
722 event_param->u.ftrace.symbol_name,
723 event);
724 if (ret) {
725 goto register_error;
726 }
727 ret = try_module_get(event->desc->owner);
728 WARN_ON_ONCE(!ret);
729 break;
730 case LTTNG_KERNEL_NOOP:
731 case LTTNG_KERNEL_SYSCALL:
732 /*
733 * Needs to be explicitly enabled after creation, since
734 * we may want to apply filters.
735 */
736 event->enabled = 0;
737 event->registered = 0;
738 event->desc = event_desc;
739 if (!event->desc) {
740 ret = -EINVAL;
741 goto register_error;
742 }
743 break;
744 case LTTNG_KERNEL_UPROBE:
745 /*
746 * Needs to be explicitly enabled after creation, since
747 * we may want to apply filters.
748 */
749 event->enabled = 0;
750 event->registered = 1;
751
752 /*
753 * Populate lttng_event structure before event
754 * registration.
755 */
756 smp_wmb();
757
758 ret = lttng_uprobes_register(event_param->name,
759 event_param->u.uprobe.fd,
760 event);
761 if (ret)
762 goto register_error;
763 ret = try_module_get(event->desc->owner);
764 WARN_ON_ONCE(!ret);
765 break;
766 default:
767 WARN_ON_ONCE(1);
768 ret = -EINVAL;
769 goto register_error;
770 }
771 ret = _lttng_event_metadata_statedump(chan->session, chan, event);
772 WARN_ON_ONCE(ret > 0);
773 if (ret) {
774 goto statedump_error;
775 }
776 hlist_add_head(&event->hlist, head);
777 list_add(&event->list, &chan->session->events);
778 return event;
779
780 statedump_error:
781 /* If a statedump error occurs, events will not be readable. */
782 register_error:
783 kmem_cache_free(event_cache, event);
784 cache_error:
785 exist:
786 type_error:
787 full:
788 return ERR_PTR(ret);
789 }
790
791 struct lttng_event *lttng_event_create(struct lttng_channel *chan,
792 struct lttng_kernel_event *event_param,
793 void *filter,
794 const struct lttng_event_desc *event_desc,
795 enum lttng_kernel_instrumentation itype)
796 {
797 struct lttng_event *event;
798
799 mutex_lock(&sessions_mutex);
800 event = _lttng_event_create(chan, event_param, filter, event_desc,
801 itype);
802 mutex_unlock(&sessions_mutex);
803 return event;
804 }
805
806 /* Only used for tracepoints for now. */
807 static
808 void register_event(struct lttng_event *event)
809 {
810 const struct lttng_event_desc *desc;
811 int ret = -EINVAL;
812
813 if (event->registered)
814 return;
815
816 desc = event->desc;
817 switch (event->instrumentation) {
818 case LTTNG_KERNEL_TRACEPOINT:
819 ret = lttng_wrapper_tracepoint_probe_register(desc->kname,
820 desc->probe_callback,
821 event);
822 break;
823 case LTTNG_KERNEL_SYSCALL:
824 ret = lttng_syscall_filter_enable(event->chan,
825 desc->name);
826 break;
827 case LTTNG_KERNEL_KPROBE:
828 case LTTNG_KERNEL_UPROBE:
829 case LTTNG_KERNEL_KRETPROBE:
830 case LTTNG_KERNEL_FUNCTION:
831 case LTTNG_KERNEL_NOOP:
832 ret = 0;
833 break;
834 default:
835 WARN_ON_ONCE(1);
836 }
837 if (!ret)
838 event->registered = 1;
839 }
840
841 /*
842 * Only used internally at session destruction.
843 */
844 int _lttng_event_unregister(struct lttng_event *event)
845 {
846 const struct lttng_event_desc *desc;
847 int ret = -EINVAL;
848
849 if (!event->registered)
850 return 0;
851
852 desc = event->desc;
853 switch (event->instrumentation) {
854 case LTTNG_KERNEL_TRACEPOINT:
855 ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname,
856 event->desc->probe_callback,
857 event);
858 break;
859 case LTTNG_KERNEL_KPROBE:
860 lttng_kprobes_unregister(event);
861 ret = 0;
862 break;
863 case LTTNG_KERNEL_KRETPROBE:
864 lttng_kretprobes_unregister(event);
865 ret = 0;
866 break;
867 case LTTNG_KERNEL_FUNCTION:
868 lttng_ftrace_unregister(event);
869 ret = 0;
870 break;
871 case LTTNG_KERNEL_SYSCALL:
872 ret = lttng_syscall_filter_disable(event->chan,
873 desc->name);
874 break;
875 case LTTNG_KERNEL_NOOP:
876 ret = 0;
877 break;
878 case LTTNG_KERNEL_UPROBE:
879 lttng_uprobes_unregister(event);
880 ret = 0;
881 break;
882 default:
883 WARN_ON_ONCE(1);
884 }
885 if (!ret)
886 event->registered = 0;
887 return ret;
888 }
889
890 /*
891 * Only used internally at session destruction.
892 */
893 static
894 void _lttng_event_destroy(struct lttng_event *event)
895 {
896 switch (event->instrumentation) {
897 case LTTNG_KERNEL_TRACEPOINT:
898 lttng_event_put(event->desc);
899 break;
900 case LTTNG_KERNEL_KPROBE:
901 module_put(event->desc->owner);
902 lttng_kprobes_destroy_private(event);
903 break;
904 case LTTNG_KERNEL_KRETPROBE:
905 module_put(event->desc->owner);
906 lttng_kretprobes_destroy_private(event);
907 break;
908 case LTTNG_KERNEL_FUNCTION:
909 module_put(event->desc->owner);
910 lttng_ftrace_destroy_private(event);
911 break;
912 case LTTNG_KERNEL_NOOP:
913 case LTTNG_KERNEL_SYSCALL:
914 break;
915 case LTTNG_KERNEL_UPROBE:
916 module_put(event->desc->owner);
917 lttng_uprobes_destroy_private(event);
918 break;
919 default:
920 WARN_ON_ONCE(1);
921 }
922 list_del(&event->list);
923 lttng_destroy_context(event->ctx);
924 kmem_cache_free(event_cache, event);
925 }
926
927 int lttng_session_track_pid(struct lttng_session *session, int pid)
928 {
929 int ret;
930
931 if (pid < -1)
932 return -EINVAL;
933 mutex_lock(&sessions_mutex);
934 if (pid == -1) {
935 /* track all pids: destroy tracker. */
936 if (session->pid_tracker) {
937 struct lttng_pid_tracker *lpf;
938
939 lpf = session->pid_tracker;
940 rcu_assign_pointer(session->pid_tracker, NULL);
941 synchronize_trace();
942 lttng_pid_tracker_destroy(lpf);
943 }
944 ret = 0;
945 } else {
946 if (!session->pid_tracker) {
947 struct lttng_pid_tracker *lpf;
948
949 lpf = lttng_pid_tracker_create();
950 if (!lpf) {
951 ret = -ENOMEM;
952 goto unlock;
953 }
954 ret = lttng_pid_tracker_add(lpf, pid);
955 rcu_assign_pointer(session->pid_tracker, lpf);
956 } else {
957 ret = lttng_pid_tracker_add(session->pid_tracker, pid);
958 }
959 }
960 unlock:
961 mutex_unlock(&sessions_mutex);
962 return ret;
963 }
964
965 int lttng_session_untrack_pid(struct lttng_session *session, int pid)
966 {
967 int ret;
968
969 if (pid < -1)
970 return -EINVAL;
971 mutex_lock(&sessions_mutex);
972 if (pid == -1) {
973 /* untrack all pids: replace by empty tracker. */
974 struct lttng_pid_tracker *old_lpf = session->pid_tracker;
975 struct lttng_pid_tracker *lpf;
976
977 lpf = lttng_pid_tracker_create();
978 if (!lpf) {
979 ret = -ENOMEM;
980 goto unlock;
981 }
982 rcu_assign_pointer(session->pid_tracker, lpf);
983 synchronize_trace();
984 if (old_lpf)
985 lttng_pid_tracker_destroy(old_lpf);
986 ret = 0;
987 } else {
988 if (!session->pid_tracker) {
989 ret = -ENOENT;
990 goto unlock;
991 }
992 ret = lttng_pid_tracker_del(session->pid_tracker, pid);
993 }
994 unlock:
995 mutex_unlock(&sessions_mutex);
996 return ret;
997 }
998
999 static
1000 void *pid_list_start(struct seq_file *m, loff_t *pos)
1001 {
1002 struct lttng_session *session = m->private;
1003 struct lttng_pid_tracker *lpf;
1004 struct lttng_pid_hash_node *e;
1005 int iter = 0, i;
1006
1007 mutex_lock(&sessions_mutex);
1008 lpf = session->pid_tracker;
1009 if (lpf) {
1010 for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) {
1011 struct hlist_head *head = &lpf->pid_hash[i];
1012
1013 lttng_hlist_for_each_entry(e, head, hlist) {
1014 if (iter++ >= *pos)
1015 return e;
1016 }
1017 }
1018 } else {
1019 /* PID tracker disabled. */
1020 if (iter >= *pos && iter == 0) {
1021 return session; /* empty tracker */
1022 }
1023 iter++;
1024 }
1025 /* End of list */
1026 return NULL;
1027 }
1028
1029 /* Called with sessions_mutex held. */
1030 static
1031 void *pid_list_next(struct seq_file *m, void *p, loff_t *ppos)
1032 {
1033 struct lttng_session *session = m->private;
1034 struct lttng_pid_tracker *lpf;
1035 struct lttng_pid_hash_node *e;
1036 int iter = 0, i;
1037
1038 (*ppos)++;
1039 lpf = session->pid_tracker;
1040 if (lpf) {
1041 for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) {
1042 struct hlist_head *head = &lpf->pid_hash[i];
1043
1044 lttng_hlist_for_each_entry(e, head, hlist) {
1045 if (iter++ >= *ppos)
1046 return e;
1047 }
1048 }
1049 } else {
1050 /* PID tracker disabled. */
1051 if (iter >= *ppos && iter == 0)
1052 return session; /* empty tracker */
1053 iter++;
1054 }
1055
1056 /* End of list */
1057 return NULL;
1058 }
1059
1060 static
1061 void pid_list_stop(struct seq_file *m, void *p)
1062 {
1063 mutex_unlock(&sessions_mutex);
1064 }
1065
1066 static
1067 int pid_list_show(struct seq_file *m, void *p)
1068 {
1069 int pid;
1070
1071 if (p == m->private) {
1072 /* Tracker disabled. */
1073 pid = -1;
1074 } else {
1075 const struct lttng_pid_hash_node *e = p;
1076
1077 pid = lttng_pid_tracker_get_node_pid(e);
1078 }
1079 seq_printf(m, "process { pid = %d; };\n", pid);
1080 return 0;
1081 }
1082
1083 static
1084 const struct seq_operations lttng_tracker_pids_list_seq_ops = {
1085 .start = pid_list_start,
1086 .next = pid_list_next,
1087 .stop = pid_list_stop,
1088 .show = pid_list_show,
1089 };
1090
1091 static
1092 int lttng_tracker_pids_list_open(struct inode *inode, struct file *file)
1093 {
1094 return seq_open(file, &lttng_tracker_pids_list_seq_ops);
1095 }
1096
1097 static
1098 int lttng_tracker_pids_list_release(struct inode *inode, struct file *file)
1099 {
1100 struct seq_file *m = file->private_data;
1101 struct lttng_session *session = m->private;
1102 int ret;
1103
1104 WARN_ON_ONCE(!session);
1105 ret = seq_release(inode, file);
1106 if (!ret && session)
1107 fput(session->file);
1108 return ret;
1109 }
1110
1111 const struct file_operations lttng_tracker_pids_list_fops = {
1112 .owner = THIS_MODULE,
1113 .open = lttng_tracker_pids_list_open,
1114 .read = seq_read,
1115 .llseek = seq_lseek,
1116 .release = lttng_tracker_pids_list_release,
1117 };
1118
1119 int lttng_session_list_tracker_pids(struct lttng_session *session)
1120 {
1121 struct file *tracker_pids_list_file;
1122 struct seq_file *m;
1123 int file_fd, ret;
1124
1125 file_fd = lttng_get_unused_fd();
1126 if (file_fd < 0) {
1127 ret = file_fd;
1128 goto fd_error;
1129 }
1130
1131 tracker_pids_list_file = anon_inode_getfile("[lttng_tracker_pids_list]",
1132 &lttng_tracker_pids_list_fops,
1133 NULL, O_RDWR);
1134 if (IS_ERR(tracker_pids_list_file)) {
1135 ret = PTR_ERR(tracker_pids_list_file);
1136 goto file_error;
1137 }
1138 if (atomic_long_add_unless(&session->file->f_count,
1139 1, INT_MAX) == INT_MAX) {
1140 goto refcount_error;
1141 }
1142 ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file);
1143 if (ret < 0)
1144 goto open_error;
1145 m = tracker_pids_list_file->private_data;
1146 m->private = session;
1147 fd_install(file_fd, tracker_pids_list_file);
1148
1149 return file_fd;
1150
1151 open_error:
1152 atomic_long_dec(&session->file->f_count);
1153 refcount_error:
1154 fput(tracker_pids_list_file);
1155 file_error:
1156 put_unused_fd(file_fd);
1157 fd_error:
1158 return ret;
1159 }
1160
1161 /*
1162 * Enabler management.
1163 */
1164 static
1165 int lttng_match_enabler_star_glob(const char *desc_name,
1166 const char *pattern)
1167 {
1168 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1169 desc_name, LTTNG_SIZE_MAX))
1170 return 0;
1171 return 1;
1172 }
1173
1174 static
1175 int lttng_match_enabler_name(const char *desc_name,
1176 const char *name)
1177 {
1178 if (strcmp(desc_name, name))
1179 return 0;
1180 return 1;
1181 }
1182
1183 static
1184 int lttng_desc_match_enabler(const struct lttng_event_desc *desc,
1185 struct lttng_enabler *enabler)
1186 {
1187 const char *desc_name, *enabler_name;
1188
1189 enabler_name = enabler->event_param.name;
1190 switch (enabler->event_param.instrumentation) {
1191 case LTTNG_KERNEL_TRACEPOINT:
1192 desc_name = desc->name;
1193 break;
1194 case LTTNG_KERNEL_SYSCALL:
1195 desc_name = desc->name;
1196 if (!strncmp(desc_name, "compat_", strlen("compat_")))
1197 desc_name += strlen("compat_");
1198 if (!strncmp(desc_name, "syscall_exit_",
1199 strlen("syscall_exit_"))) {
1200 desc_name += strlen("syscall_exit_");
1201 } else if (!strncmp(desc_name, "syscall_entry_",
1202 strlen("syscall_entry_"))) {
1203 desc_name += strlen("syscall_entry_");
1204 } else {
1205 WARN_ON_ONCE(1);
1206 return -EINVAL;
1207 }
1208 break;
1209 default:
1210 WARN_ON_ONCE(1);
1211 return -EINVAL;
1212 }
1213 switch (enabler->type) {
1214 case LTTNG_ENABLER_STAR_GLOB:
1215 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1216 case LTTNG_ENABLER_NAME:
1217 return lttng_match_enabler_name(desc_name, enabler_name);
1218 default:
1219 return -EINVAL;
1220 }
1221 }
1222
1223 static
1224 int lttng_event_match_enabler(struct lttng_event *event,
1225 struct lttng_enabler *enabler)
1226 {
1227 if (enabler->event_param.instrumentation != event->instrumentation)
1228 return 0;
1229 if (lttng_desc_match_enabler(event->desc, enabler)
1230 && event->chan == enabler->chan)
1231 return 1;
1232 else
1233 return 0;
1234 }
1235
1236 static
1237 struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event,
1238 struct lttng_enabler *enabler)
1239 {
1240 struct lttng_enabler_ref *enabler_ref;
1241
1242 list_for_each_entry(enabler_ref,
1243 &event->enablers_ref_head, node) {
1244 if (enabler_ref->ref == enabler)
1245 return enabler_ref;
1246 }
1247 return NULL;
1248 }
1249
1250 static
1251 void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler)
1252 {
1253 struct lttng_session *session = enabler->chan->session;
1254 struct lttng_probe_desc *probe_desc;
1255 const struct lttng_event_desc *desc;
1256 int i;
1257 struct list_head *probe_list;
1258
1259 probe_list = lttng_get_probe_list_head();
1260 /*
1261 * For each probe event, if we find that a probe event matches
1262 * our enabler, create an associated lttng_event if not
1263 * already present.
1264 */
1265 list_for_each_entry(probe_desc, probe_list, head) {
1266 for (i = 0; i < probe_desc->nr_events; i++) {
1267 int found = 0;
1268 struct hlist_head *head;
1269 const char *event_name;
1270 size_t name_len;
1271 uint32_t hash;
1272 struct lttng_event *event;
1273
1274 desc = probe_desc->event_desc[i];
1275 if (!lttng_desc_match_enabler(desc, enabler))
1276 continue;
1277 event_name = desc->name;
1278 name_len = strlen(event_name);
1279
1280 /*
1281 * Check if already created.
1282 */
1283 hash = jhash(event_name, name_len, 0);
1284 head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
1285 lttng_hlist_for_each_entry(event, head, hlist) {
1286 if (event->desc == desc
1287 && event->chan == enabler->chan)
1288 found = 1;
1289 }
1290 if (found)
1291 continue;
1292
1293 /*
1294 * We need to create an event for this
1295 * event probe.
1296 */
1297 event = _lttng_event_create(enabler->chan,
1298 NULL, NULL, desc,
1299 LTTNG_KERNEL_TRACEPOINT);
1300 if (!event) {
1301 printk(KERN_INFO "Unable to create event %s\n",
1302 probe_desc->event_desc[i]->name);
1303 }
1304 }
1305 }
1306 }
1307
1308 static
1309 void lttng_create_syscall_if_missing(struct lttng_enabler *enabler)
1310 {
1311 int ret;
1312
1313 ret = lttng_syscalls_register(enabler->chan, NULL);
1314 WARN_ON_ONCE(ret);
1315 }
1316
1317 /*
1318 * Create struct lttng_event if it is missing and present in the list of
1319 * tracepoint probes.
1320 * Should be called with sessions mutex held.
1321 */
1322 static
1323 void lttng_create_event_if_missing(struct lttng_enabler *enabler)
1324 {
1325 switch (enabler->event_param.instrumentation) {
1326 case LTTNG_KERNEL_TRACEPOINT:
1327 lttng_create_tracepoint_if_missing(enabler);
1328 break;
1329 case LTTNG_KERNEL_SYSCALL:
1330 lttng_create_syscall_if_missing(enabler);
1331 break;
1332 default:
1333 WARN_ON_ONCE(1);
1334 break;
1335 }
1336 }
1337
1338 /*
1339 * Create events associated with an enabler (if not already present),
1340 * and add backward reference from the event to the enabler.
1341 * Should be called with sessions mutex held.
1342 */
1343 static
1344 int lttng_enabler_ref_events(struct lttng_enabler *enabler)
1345 {
1346 struct lttng_session *session = enabler->chan->session;
1347 struct lttng_event *event;
1348
1349 /* First ensure that probe events are created for this enabler. */
1350 lttng_create_event_if_missing(enabler);
1351
1352 /* For each event matching enabler in session event list. */
1353 list_for_each_entry(event, &session->events, list) {
1354 struct lttng_enabler_ref *enabler_ref;
1355
1356 if (!lttng_event_match_enabler(event, enabler))
1357 continue;
1358 enabler_ref = lttng_event_enabler_ref(event, enabler);
1359 if (!enabler_ref) {
1360 /*
1361 * If no backward ref, create it.
1362 * Add backward ref from event to enabler.
1363 */
1364 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
1365 if (!enabler_ref)
1366 return -ENOMEM;
1367 enabler_ref->ref = enabler;
1368 list_add(&enabler_ref->node,
1369 &event->enablers_ref_head);
1370 }
1371
1372 /*
1373 * Link filter bytecodes if not linked yet.
1374 */
1375 lttng_enabler_event_link_bytecode(event, enabler);
1376
1377 /* TODO: merge event context. */
1378 }
1379 return 0;
1380 }
1381
1382 /*
1383 * Called at module load: connect the probe on all enablers matching
1384 * this event.
1385 * Called with sessions lock held.
1386 */
1387 int lttng_fix_pending_events(void)
1388 {
1389 struct lttng_session *session;
1390
1391 list_for_each_entry(session, &sessions, list)
1392 lttng_session_lazy_sync_enablers(session);
1393 return 0;
1394 }
1395
1396 struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
1397 struct lttng_kernel_event *event_param,
1398 struct lttng_channel *chan)
1399 {
1400 struct lttng_enabler *enabler;
1401
1402 enabler = kzalloc(sizeof(*enabler), GFP_KERNEL);
1403 if (!enabler)
1404 return NULL;
1405 enabler->type = type;
1406 INIT_LIST_HEAD(&enabler->filter_bytecode_head);
1407 memcpy(&enabler->event_param, event_param,
1408 sizeof(enabler->event_param));
1409 enabler->chan = chan;
1410 /* ctx left NULL */
1411 enabler->enabled = 0;
1412 enabler->evtype = LTTNG_TYPE_ENABLER;
1413 mutex_lock(&sessions_mutex);
1414 list_add(&enabler->node, &enabler->chan->session->enablers_head);
1415 lttng_session_lazy_sync_enablers(enabler->chan->session);
1416 mutex_unlock(&sessions_mutex);
1417 return enabler;
1418 }
1419
1420 int lttng_enabler_enable(struct lttng_enabler *enabler)
1421 {
1422 mutex_lock(&sessions_mutex);
1423 enabler->enabled = 1;
1424 lttng_session_lazy_sync_enablers(enabler->chan->session);
1425 mutex_unlock(&sessions_mutex);
1426 return 0;
1427 }
1428
1429 int lttng_enabler_disable(struct lttng_enabler *enabler)
1430 {
1431 mutex_lock(&sessions_mutex);
1432 enabler->enabled = 0;
1433 lttng_session_lazy_sync_enablers(enabler->chan->session);
1434 mutex_unlock(&sessions_mutex);
1435 return 0;
1436 }
1437
1438 int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
1439 struct lttng_kernel_filter_bytecode __user *bytecode)
1440 {
1441 struct lttng_filter_bytecode_node *bytecode_node;
1442 uint32_t bytecode_len;
1443 int ret;
1444
1445 ret = get_user(bytecode_len, &bytecode->len);
1446 if (ret)
1447 return ret;
1448 bytecode_node = kzalloc(sizeof(*bytecode_node) + bytecode_len,
1449 GFP_KERNEL);
1450 if (!bytecode_node)
1451 return -ENOMEM;
1452 ret = copy_from_user(&bytecode_node->bc, bytecode,
1453 sizeof(*bytecode) + bytecode_len);
1454 if (ret)
1455 goto error_free;
1456 bytecode_node->enabler = enabler;
1457 /* Enforce length based on allocated size */
1458 bytecode_node->bc.len = bytecode_len;
1459 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
1460 lttng_session_lazy_sync_enablers(enabler->chan->session);
1461 return 0;
1462
1463 error_free:
1464 kfree(bytecode_node);
1465 return ret;
1466 }
1467
1468 int lttng_event_add_callsite(struct lttng_event *event,
1469 struct lttng_kernel_event_callsite __user *callsite)
1470 {
1471
1472 switch (event->instrumentation) {
1473 case LTTNG_KERNEL_UPROBE:
1474 return lttng_uprobes_add_callsite(event, callsite);
1475 default:
1476 return -EINVAL;
1477 }
1478 }
1479
1480 int lttng_enabler_attach_context(struct lttng_enabler *enabler,
1481 struct lttng_kernel_context *context_param)
1482 {
1483 return -ENOSYS;
1484 }
1485
1486 static
1487 void lttng_enabler_destroy(struct lttng_enabler *enabler)
1488 {
1489 struct lttng_filter_bytecode_node *filter_node, *tmp_filter_node;
1490
1491 /* Destroy filter bytecode */
1492 list_for_each_entry_safe(filter_node, tmp_filter_node,
1493 &enabler->filter_bytecode_head, node) {
1494 kfree(filter_node);
1495 }
1496
1497 /* Destroy contexts */
1498 lttng_destroy_context(enabler->ctx);
1499
1500 list_del(&enabler->node);
1501 kfree(enabler);
1502 }
1503
1504 /*
1505 * lttng_session_sync_enablers should be called just before starting a
1506 * session.
1507 * Should be called with sessions mutex held.
1508 */
1509 static
1510 void lttng_session_sync_enablers(struct lttng_session *session)
1511 {
1512 struct lttng_enabler *enabler;
1513 struct lttng_event *event;
1514
1515 list_for_each_entry(enabler, &session->enablers_head, node)
1516 lttng_enabler_ref_events(enabler);
1517 /*
1518 * For each event, if at least one of its enablers is enabled,
1519 * and its channel and session transient states are enabled, we
1520 * enable the event, else we disable it.
1521 */
1522 list_for_each_entry(event, &session->events, list) {
1523 struct lttng_enabler_ref *enabler_ref;
1524 struct lttng_bytecode_runtime *runtime;
1525 int enabled = 0, has_enablers_without_bytecode = 0;
1526
1527 switch (event->instrumentation) {
1528 case LTTNG_KERNEL_TRACEPOINT:
1529 case LTTNG_KERNEL_SYSCALL:
1530 /* Enable events */
1531 list_for_each_entry(enabler_ref,
1532 &event->enablers_ref_head, node) {
1533 if (enabler_ref->ref->enabled) {
1534 enabled = 1;
1535 break;
1536 }
1537 }
1538 break;
1539 default:
1540 /* Not handled with lazy sync. */
1541 continue;
1542 }
1543 /*
1544 * Enabled state is based on union of enablers, with
1545 * intesection of session and channel transient enable
1546 * states.
1547 */
1548 enabled = enabled && session->tstate && event->chan->tstate;
1549
1550 WRITE_ONCE(event->enabled, enabled);
1551 /*
1552 * Sync tracepoint registration with event enabled
1553 * state.
1554 */
1555 if (enabled) {
1556 register_event(event);
1557 } else {
1558 _lttng_event_unregister(event);
1559 }
1560
1561 /* Check if has enablers without bytecode enabled */
1562 list_for_each_entry(enabler_ref,
1563 &event->enablers_ref_head, node) {
1564 if (enabler_ref->ref->enabled
1565 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
1566 has_enablers_without_bytecode = 1;
1567 break;
1568 }
1569 }
1570 event->has_enablers_without_bytecode =
1571 has_enablers_without_bytecode;
1572
1573 /* Enable filters */
1574 list_for_each_entry(runtime,
1575 &event->bytecode_runtime_head, node)
1576 lttng_filter_sync_state(runtime);
1577 }
1578 }
1579
1580 /*
1581 * Apply enablers to session events, adding events to session if need
1582 * be. It is required after each modification applied to an active
1583 * session, and right before session "start".
1584 * "lazy" sync means we only sync if required.
1585 * Should be called with sessions mutex held.
1586 */
1587 static
1588 void lttng_session_lazy_sync_enablers(struct lttng_session *session)
1589 {
1590 /* We can skip if session is not active */
1591 if (!session->active)
1592 return;
1593 lttng_session_sync_enablers(session);
1594 }
1595
1596 /*
1597 * Serialize at most one packet worth of metadata into a metadata
1598 * channel.
1599 * We grab the metadata cache mutex to get exclusive access to our metadata
1600 * buffer and to the metadata cache. Exclusive access to the metadata buffer
1601 * allows us to do racy operations such as looking for remaining space left in
1602 * packet and write, since mutual exclusion protects us from concurrent writes.
1603 * Mutual exclusion on the metadata cache allow us to read the cache content
1604 * without racing against reallocation of the cache by updates.
1605 * Returns the number of bytes written in the channel, 0 if no data
1606 * was written and a negative value on error.
1607 */
1608 int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
1609 struct channel *chan)
1610 {
1611 struct lib_ring_buffer_ctx ctx;
1612 int ret = 0;
1613 size_t len, reserve_len;
1614
1615 /*
1616 * Ensure we support mutiple get_next / put sequences followed by
1617 * put_next. The metadata cache lock protects reading the metadata
1618 * cache. It can indeed be read concurrently by "get_next_subbuf" and
1619 * "flush" operations on the buffer invoked by different processes.
1620 * Moreover, since the metadata cache memory can be reallocated, we
1621 * need to have exclusive access against updates even though we only
1622 * read it.
1623 */
1624 mutex_lock(&stream->metadata_cache->lock);
1625 WARN_ON(stream->metadata_in < stream->metadata_out);
1626 if (stream->metadata_in != stream->metadata_out)
1627 goto end;
1628
1629 /* Metadata regenerated, change the version. */
1630 if (stream->metadata_cache->version != stream->version)
1631 stream->version = stream->metadata_cache->version;
1632
1633 len = stream->metadata_cache->metadata_written -
1634 stream->metadata_in;
1635 if (!len)
1636 goto end;
1637 reserve_len = min_t(size_t,
1638 stream->transport->ops.packet_avail_size(chan),
1639 len);
1640 lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len,
1641 sizeof(char), -1);
1642 /*
1643 * If reservation failed, return an error to the caller.
1644 */
1645 ret = stream->transport->ops.event_reserve(&ctx, 0);
1646 if (ret != 0) {
1647 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
1648 goto end;
1649 }
1650 stream->transport->ops.event_write(&ctx,
1651 stream->metadata_cache->data + stream->metadata_in,
1652 reserve_len);
1653 stream->transport->ops.event_commit(&ctx);
1654 stream->metadata_in += reserve_len;
1655 ret = reserve_len;
1656
1657 end:
1658 mutex_unlock(&stream->metadata_cache->lock);
1659 return ret;
1660 }
1661
1662 /*
1663 * Write the metadata to the metadata cache.
1664 * Must be called with sessions_mutex held.
1665 * The metadata cache lock protects us from concurrent read access from
1666 * thread outputting metadata content to ring buffer.
1667 */
1668 int lttng_metadata_printf(struct lttng_session *session,
1669 const char *fmt, ...)
1670 {
1671 char *str;
1672 size_t len;
1673 va_list ap;
1674 struct lttng_metadata_stream *stream;
1675
1676 WARN_ON_ONCE(!READ_ONCE(session->active));
1677
1678 va_start(ap, fmt);
1679 str = kvasprintf(GFP_KERNEL, fmt, ap);
1680 va_end(ap);
1681 if (!str)
1682 return -ENOMEM;
1683
1684 len = strlen(str);
1685 mutex_lock(&session->metadata_cache->lock);
1686 if (session->metadata_cache->metadata_written + len >
1687 session->metadata_cache->cache_alloc) {
1688 char *tmp_cache_realloc;
1689 unsigned int tmp_cache_alloc_size;
1690
1691 tmp_cache_alloc_size = max_t(unsigned int,
1692 session->metadata_cache->cache_alloc + len,
1693 session->metadata_cache->cache_alloc << 1);
1694 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
1695 if (!tmp_cache_realloc)
1696 goto err;
1697 if (session->metadata_cache->data) {
1698 memcpy(tmp_cache_realloc,
1699 session->metadata_cache->data,
1700 session->metadata_cache->cache_alloc);
1701 vfree(session->metadata_cache->data);
1702 }
1703
1704 session->metadata_cache->cache_alloc = tmp_cache_alloc_size;
1705 session->metadata_cache->data = tmp_cache_realloc;
1706 }
1707 memcpy(session->metadata_cache->data +
1708 session->metadata_cache->metadata_written,
1709 str, len);
1710 session->metadata_cache->metadata_written += len;
1711 mutex_unlock(&session->metadata_cache->lock);
1712 kfree(str);
1713
1714 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
1715 wake_up_interruptible(&stream->read_wait);
1716
1717 return 0;
1718
1719 err:
1720 mutex_unlock(&session->metadata_cache->lock);
1721 kfree(str);
1722 return -ENOMEM;
1723 }
1724
1725 static
1726 int print_tabs(struct lttng_session *session, size_t nesting)
1727 {
1728 size_t i;
1729
1730 for (i = 0; i < nesting; i++) {
1731 int ret;
1732
1733 ret = lttng_metadata_printf(session, " ");
1734 if (ret) {
1735 return ret;
1736 }
1737 }
1738 return 0;
1739 }
1740
1741 /*
1742 * Must be called with sessions_mutex held.
1743 */
1744 static
1745 int _lttng_struct_type_statedump(struct lttng_session *session,
1746 const struct lttng_type *type,
1747 size_t nesting)
1748 {
1749 int ret;
1750 uint32_t i, nr_fields;
1751
1752 ret = print_tabs(session, nesting);
1753 if (ret)
1754 return ret;
1755 ret = lttng_metadata_printf(session,
1756 "struct {\n");
1757 if (ret)
1758 return ret;
1759 nr_fields = type->u._struct.nr_fields;
1760 for (i = 0; i < nr_fields; i++) {
1761 const struct lttng_event_field *iter_field;
1762
1763 iter_field = &type->u._struct.fields[i];
1764 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
1765 if (ret)
1766 return ret;
1767 }
1768 ret = print_tabs(session, nesting);
1769 if (ret)
1770 return ret;
1771 ret = lttng_metadata_printf(session,
1772 "}");
1773 return ret;
1774 }
1775
1776 /*
1777 * Must be called with sessions_mutex held.
1778 */
1779 static
1780 int _lttng_struct_statedump(struct lttng_session *session,
1781 const struct lttng_event_field *field,
1782 size_t nesting)
1783 {
1784 int ret;
1785
1786 ret = _lttng_struct_type_statedump(session,
1787 &field->type, nesting);
1788 if (ret)
1789 return ret;
1790 ret = lttng_metadata_printf(session,
1791 "_%s;\n",
1792 field->name);
1793 return ret;
1794 }
1795
1796 /*
1797 * Must be called with sessions_mutex held.
1798 */
1799 static
1800 int _lttng_variant_type_statedump(struct lttng_session *session,
1801 const struct lttng_type *type,
1802 size_t nesting)
1803 {
1804 int ret;
1805 uint32_t i, nr_choices;
1806
1807 ret = print_tabs(session, nesting);
1808 if (ret)
1809 return ret;
1810 ret = lttng_metadata_printf(session,
1811 "variant <_%s> {\n",
1812 type->u.variant.tag_name);
1813 if (ret)
1814 return ret;
1815 nr_choices = type->u.variant.nr_choices;
1816 for (i = 0; i < nr_choices; i++) {
1817 const struct lttng_event_field *iter_field;
1818
1819 iter_field = &type->u.variant.choices[i];
1820 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
1821 if (ret)
1822 return ret;
1823 }
1824 ret = print_tabs(session, nesting);
1825 if (ret)
1826 return ret;
1827 ret = lttng_metadata_printf(session,
1828 "}");
1829 return ret;
1830 }
1831
1832 /*
1833 * Must be called with sessions_mutex held.
1834 */
1835 static
1836 int _lttng_variant_statedump(struct lttng_session *session,
1837 const struct lttng_event_field *field,
1838 size_t nesting)
1839 {
1840 int ret;
1841
1842 ret = _lttng_variant_type_statedump(session,
1843 &field->type, nesting);
1844 if (ret)
1845 return ret;
1846 ret = lttng_metadata_printf(session,
1847 "_%s;\n",
1848 field->name);
1849 return ret;
1850 }
1851
1852 /*
1853 * Must be called with sessions_mutex held.
1854 */
1855 static
1856 int _lttng_array_compound_statedump(struct lttng_session *session,
1857 const struct lttng_event_field *field,
1858 size_t nesting)
1859 {
1860 int ret;
1861 const struct lttng_type *elem_type;
1862
1863 /* Only array of structures and variants are currently supported. */
1864 elem_type = field->type.u.array_compound.elem_type;
1865 switch (elem_type->atype) {
1866 case atype_struct:
1867 ret = _lttng_struct_type_statedump(session, elem_type, nesting);
1868 if (ret)
1869 return ret;
1870 break;
1871 case atype_variant:
1872 ret = _lttng_variant_type_statedump(session, elem_type, nesting);
1873 if (ret)
1874 return ret;
1875 break;
1876 default:
1877 return -EINVAL;
1878 }
1879 ret = lttng_metadata_printf(session,
1880 " _%s[%u];\n",
1881 field->name,
1882 field->type.u.array_compound.length);
1883 return ret;
1884 }
1885
1886 /*
1887 * Must be called with sessions_mutex held.
1888 */
1889 static
1890 int _lttng_sequence_compound_statedump(struct lttng_session *session,
1891 const struct lttng_event_field *field,
1892 size_t nesting)
1893 {
1894 int ret;
1895 const char *length_name;
1896 const struct lttng_type *elem_type;
1897
1898 length_name = field->type.u.sequence_compound.length_name;
1899
1900 /* Only array of structures and variants are currently supported. */
1901 elem_type = field->type.u.sequence_compound.elem_type;
1902 switch (elem_type->atype) {
1903 case atype_struct:
1904 ret = _lttng_struct_type_statedump(session, elem_type, nesting);
1905 if (ret)
1906 return ret;
1907 break;
1908 case atype_variant:
1909 ret = _lttng_variant_type_statedump(session, elem_type, nesting);
1910 if (ret)
1911 return ret;
1912 break;
1913 default:
1914 return -EINVAL;
1915 }
1916 ret = lttng_metadata_printf(session,
1917 " _%s[ _%s ];\n",
1918 field->name,
1919 length_name);
1920 return ret;
1921 }
1922
1923 /*
1924 * Must be called with sessions_mutex held.
1925 */
1926 static
1927 int _lttng_enum_statedump(struct lttng_session *session,
1928 const struct lttng_event_field *field,
1929 size_t nesting)
1930 {
1931 const struct lttng_enum_desc *enum_desc;
1932 const struct lttng_integer_type *container_type;
1933 int ret;
1934 unsigned int i, nr_entries;
1935
1936 enum_desc = field->type.u.basic.enumeration.desc;
1937 container_type = &field->type.u.basic.enumeration.container_type;
1938 nr_entries = enum_desc->nr_entries;
1939
1940 ret = print_tabs(session, nesting);
1941 if (ret)
1942 goto end;
1943 ret = lttng_metadata_printf(session,
1944 "enum : integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } {\n",
1945 container_type->size,
1946 container_type->alignment,
1947 container_type->signedness,
1948 (container_type->encoding == lttng_encode_none)
1949 ? "none"
1950 : (container_type->encoding == lttng_encode_UTF8)
1951 ? "UTF8"
1952 : "ASCII",
1953 container_type->base,
1954 #if __BYTE_ORDER == __BIG_ENDIAN
1955 container_type->reverse_byte_order ? " byte_order = le;" : ""
1956 #else
1957 container_type->reverse_byte_order ? " byte_order = be;" : ""
1958 #endif
1959 );
1960 if (ret)
1961 goto end;
1962 /* Dump all entries */
1963 for (i = 0; i < nr_entries; i++) {
1964 const struct lttng_enum_entry *entry = &enum_desc->entries[i];
1965 int j, len;
1966
1967 ret = print_tabs(session, nesting + 1);
1968 if (ret)
1969 goto end;
1970 ret = lttng_metadata_printf(session,
1971 "\"");
1972 if (ret)
1973 goto end;
1974 len = strlen(entry->string);
1975 /* Escape the character '"' */
1976 for (j = 0; j < len; j++) {
1977 char c = entry->string[j];
1978
1979 switch (c) {
1980 case '"':
1981 ret = lttng_metadata_printf(session,
1982 "\\\"");
1983 break;
1984 case '\\':
1985 ret = lttng_metadata_printf(session,
1986 "\\\\");
1987 break;
1988 default:
1989 ret = lttng_metadata_printf(session,
1990 "%c", c);
1991 break;
1992 }
1993 if (ret)
1994 goto end;
1995 }
1996 ret = lttng_metadata_printf(session, "\"");
1997 if (ret)
1998 goto end;
1999
2000 if (entry->options.is_auto) {
2001 ret = lttng_metadata_printf(session, ",\n");
2002 if (ret)
2003 goto end;
2004 } else {
2005 ret = lttng_metadata_printf(session,
2006 " = ");
2007 if (ret)
2008 goto end;
2009 if (entry->start.signedness)
2010 ret = lttng_metadata_printf(session,
2011 "%lld", (long long) entry->start.value);
2012 else
2013 ret = lttng_metadata_printf(session,
2014 "%llu", entry->start.value);
2015 if (ret)
2016 goto end;
2017 if (entry->start.signedness == entry->end.signedness &&
2018 entry->start.value
2019 == entry->end.value) {
2020 ret = lttng_metadata_printf(session,
2021 ",\n");
2022 } else {
2023 if (entry->end.signedness) {
2024 ret = lttng_metadata_printf(session,
2025 " ... %lld,\n",
2026 (long long) entry->end.value);
2027 } else {
2028 ret = lttng_metadata_printf(session,
2029 " ... %llu,\n",
2030 entry->end.value);
2031 }
2032 }
2033 if (ret)
2034 goto end;
2035 }
2036 }
2037 ret = print_tabs(session, nesting);
2038 if (ret)
2039 goto end;
2040 ret = lttng_metadata_printf(session, "} _%s;\n",
2041 field->name);
2042 end:
2043 return ret;
2044 }
2045
2046 /*
2047 * Must be called with sessions_mutex held.
2048 */
2049 static
2050 int _lttng_field_statedump(struct lttng_session *session,
2051 const struct lttng_event_field *field,
2052 size_t nesting)
2053 {
2054 int ret = 0;
2055
2056 switch (field->type.atype) {
2057 case atype_integer:
2058 ret = print_tabs(session, nesting);
2059 if (ret)
2060 return ret;
2061 ret = lttng_metadata_printf(session,
2062 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
2063 field->type.u.basic.integer.size,
2064 field->type.u.basic.integer.alignment,
2065 field->type.u.basic.integer.signedness,
2066 (field->type.u.basic.integer.encoding == lttng_encode_none)
2067 ? "none"
2068 : (field->type.u.basic.integer.encoding == lttng_encode_UTF8)
2069 ? "UTF8"
2070 : "ASCII",
2071 field->type.u.basic.integer.base,
2072 #if __BYTE_ORDER == __BIG_ENDIAN
2073 field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
2074 #else
2075 field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
2076 #endif
2077 field->name);
2078 break;
2079 case atype_enum:
2080 ret = _lttng_enum_statedump(session, field, nesting);
2081 break;
2082 case atype_array:
2083 case atype_array_bitfield:
2084 {
2085 const struct lttng_basic_type *elem_type;
2086
2087 elem_type = &field->type.u.array.elem_type;
2088 if (field->type.u.array.elem_alignment) {
2089 ret = print_tabs(session, nesting);
2090 if (ret)
2091 return ret;
2092 ret = lttng_metadata_printf(session,
2093 "struct { } align(%u) _%s_padding;\n",
2094 field->type.u.array.elem_alignment * CHAR_BIT,
2095 field->name);
2096 if (ret)
2097 return ret;
2098 }
2099 ret = print_tabs(session, nesting);
2100 if (ret)
2101 return ret;
2102 ret = lttng_metadata_printf(session,
2103 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
2104 elem_type->u.basic.integer.size,
2105 elem_type->u.basic.integer.alignment,
2106 elem_type->u.basic.integer.signedness,
2107 (elem_type->u.basic.integer.encoding == lttng_encode_none)
2108 ? "none"
2109 : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8)
2110 ? "UTF8"
2111 : "ASCII",
2112 elem_type->u.basic.integer.base,
2113 #if __BYTE_ORDER == __BIG_ENDIAN
2114 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
2115 #else
2116 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
2117 #endif
2118 field->name, field->type.u.array.length);
2119 break;
2120 }
2121 case atype_sequence:
2122 case atype_sequence_bitfield:
2123 {
2124 const struct lttng_basic_type *elem_type;
2125 const struct lttng_basic_type *length_type;
2126
2127 elem_type = &field->type.u.sequence.elem_type;
2128 length_type = &field->type.u.sequence.length_type;
2129 ret = print_tabs(session, nesting);
2130 if (ret)
2131 return ret;
2132 ret = lttng_metadata_printf(session,
2133 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
2134 length_type->u.basic.integer.size,
2135 (unsigned int) length_type->u.basic.integer.alignment,
2136 length_type->u.basic.integer.signedness,
2137 (length_type->u.basic.integer.encoding == lttng_encode_none)
2138 ? "none"
2139 : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8)
2140 ? "UTF8"
2141 : "ASCII"),
2142 length_type->u.basic.integer.base,
2143 #if __BYTE_ORDER == __BIG_ENDIAN
2144 length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
2145 #else
2146 length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
2147 #endif
2148 field->name);
2149 if (ret)
2150 return ret;
2151
2152 if (field->type.u.sequence.elem_alignment) {
2153 ret = print_tabs(session, nesting);
2154 if (ret)
2155 return ret;
2156 ret = lttng_metadata_printf(session,
2157 "struct { } align(%u) _%s_padding;\n",
2158 field->type.u.sequence.elem_alignment * CHAR_BIT,
2159 field->name);
2160 if (ret)
2161 return ret;
2162 }
2163 ret = print_tabs(session, nesting);
2164 if (ret)
2165 return ret;
2166 ret = lttng_metadata_printf(session,
2167 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
2168 elem_type->u.basic.integer.size,
2169 (unsigned int) elem_type->u.basic.integer.alignment,
2170 elem_type->u.basic.integer.signedness,
2171 (elem_type->u.basic.integer.encoding == lttng_encode_none)
2172 ? "none"
2173 : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8)
2174 ? "UTF8"
2175 : "ASCII"),
2176 elem_type->u.basic.integer.base,
2177 #if __BYTE_ORDER == __BIG_ENDIAN
2178 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
2179 #else
2180 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
2181 #endif
2182 field->name,
2183 field->name);
2184 break;
2185 }
2186
2187 case atype_string:
2188 /* Default encoding is UTF8 */
2189 ret = print_tabs(session, nesting);
2190 if (ret)
2191 return ret;
2192 ret = lttng_metadata_printf(session,
2193 "string%s _%s;\n",
2194 field->type.u.basic.string.encoding == lttng_encode_ASCII ?
2195 " { encoding = ASCII; }" : "",
2196 field->name);
2197 break;
2198 case atype_struct:
2199 ret = _lttng_struct_statedump(session, field, nesting);
2200 break;
2201 case atype_array_compound:
2202 ret = _lttng_array_compound_statedump(session, field, nesting);
2203 break;
2204 case atype_sequence_compound:
2205 ret = _lttng_sequence_compound_statedump(session, field, nesting);
2206 break;
2207 case atype_variant:
2208 ret = _lttng_variant_statedump(session, field, nesting);
2209 break;
2210
2211 default:
2212 WARN_ON_ONCE(1);
2213 return -EINVAL;
2214 }
2215 return ret;
2216 }
2217
2218 static
2219 int _lttng_context_metadata_statedump(struct lttng_session *session,
2220 struct lttng_ctx *ctx)
2221 {
2222 int ret = 0;
2223 int i;
2224
2225 if (!ctx)
2226 return 0;
2227 for (i = 0; i < ctx->nr_fields; i++) {
2228 const struct lttng_ctx_field *field = &ctx->fields[i];
2229
2230 ret = _lttng_field_statedump(session, &field->event_field, 2);
2231 if (ret)
2232 return ret;
2233 }
2234 return ret;
2235 }
2236
2237 static
2238 int _lttng_fields_metadata_statedump(struct lttng_session *session,
2239 struct lttng_event *event)
2240 {
2241 const struct lttng_event_desc *desc = event->desc;
2242 int ret = 0;
2243 int i;
2244
2245 for (i = 0; i < desc->nr_fields; i++) {
2246 const struct lttng_event_field *field = &desc->fields[i];
2247
2248 ret = _lttng_field_statedump(session, field, 2);
2249 if (ret)
2250 return ret;
2251 }
2252 return ret;
2253 }
2254
2255 /*
2256 * Must be called with sessions_mutex held.
2257 */
2258 static
2259 int _lttng_event_metadata_statedump(struct lttng_session *session,
2260 struct lttng_channel *chan,
2261 struct lttng_event *event)
2262 {
2263 int ret = 0;
2264
2265 if (event->metadata_dumped || !READ_ONCE(session->active))
2266 return 0;
2267 if (chan->channel_type == METADATA_CHANNEL)
2268 return 0;
2269
2270 ret = lttng_metadata_printf(session,
2271 "event {\n"
2272 " name = \"%s\";\n"
2273 " id = %u;\n"
2274 " stream_id = %u;\n",
2275 event->desc->name,
2276 event->id,
2277 event->chan->id);
2278 if (ret)
2279 goto end;
2280
2281 if (event->ctx) {
2282 ret = lttng_metadata_printf(session,
2283 " context := struct {\n");
2284 if (ret)
2285 goto end;
2286 }
2287 ret = _lttng_context_metadata_statedump(session, event->ctx);
2288 if (ret)
2289 goto end;
2290 if (event->ctx) {
2291 ret = lttng_metadata_printf(session,
2292 " };\n");
2293 if (ret)
2294 goto end;
2295 }
2296
2297 ret = lttng_metadata_printf(session,
2298 " fields := struct {\n"
2299 );
2300 if (ret)
2301 goto end;
2302
2303 ret = _lttng_fields_metadata_statedump(session, event);
2304 if (ret)
2305 goto end;
2306
2307 /*
2308 * LTTng space reservation can only reserve multiples of the
2309 * byte size.
2310 */
2311 ret = lttng_metadata_printf(session,
2312 " };\n"
2313 "};\n\n");
2314 if (ret)
2315 goto end;
2316
2317 event->metadata_dumped = 1;
2318 end:
2319 return ret;
2320
2321 }
2322
2323 /*
2324 * Must be called with sessions_mutex held.
2325 */
2326 static
2327 int _lttng_channel_metadata_statedump(struct lttng_session *session,
2328 struct lttng_channel *chan)
2329 {
2330 int ret = 0;
2331
2332 if (chan->metadata_dumped || !READ_ONCE(session->active))
2333 return 0;
2334
2335 if (chan->channel_type == METADATA_CHANNEL)
2336 return 0;
2337
2338 WARN_ON_ONCE(!chan->header_type);
2339 ret = lttng_metadata_printf(session,
2340 "stream {\n"
2341 " id = %u;\n"
2342 " event.header := %s;\n"
2343 " packet.context := struct packet_context;\n",
2344 chan->id,
2345 chan->header_type == 1 ? "struct event_header_compact" :
2346 "struct event_header_large");
2347 if (ret)
2348 goto end;
2349
2350 if (chan->ctx) {
2351 ret = lttng_metadata_printf(session,
2352 " event.context := struct {\n");
2353 if (ret)
2354 goto end;
2355 }
2356 ret = _lttng_context_metadata_statedump(session, chan->ctx);
2357 if (ret)
2358 goto end;
2359 if (chan->ctx) {
2360 ret = lttng_metadata_printf(session,
2361 " };\n");
2362 if (ret)
2363 goto end;
2364 }
2365
2366 ret = lttng_metadata_printf(session,
2367 "};\n\n");
2368
2369 chan->metadata_dumped = 1;
2370 end:
2371 return ret;
2372 }
2373
2374 /*
2375 * Must be called with sessions_mutex held.
2376 */
2377 static
2378 int _lttng_stream_packet_context_declare(struct lttng_session *session)
2379 {
2380 return lttng_metadata_printf(session,
2381 "struct packet_context {\n"
2382 " uint64_clock_monotonic_t timestamp_begin;\n"
2383 " uint64_clock_monotonic_t timestamp_end;\n"
2384 " uint64_t content_size;\n"
2385 " uint64_t packet_size;\n"
2386 " uint64_t packet_seq_num;\n"
2387 " unsigned long events_discarded;\n"
2388 " uint32_t cpu_id;\n"
2389 "};\n\n"
2390 );
2391 }
2392
2393 /*
2394 * Compact header:
2395 * id: range: 0 - 30.
2396 * id 31 is reserved to indicate an extended header.
2397 *
2398 * Large header:
2399 * id: range: 0 - 65534.
2400 * id 65535 is reserved to indicate an extended header.
2401 *
2402 * Must be called with sessions_mutex held.
2403 */
2404 static
2405 int _lttng_event_header_declare(struct lttng_session *session)
2406 {
2407 return lttng_metadata_printf(session,
2408 "struct event_header_compact {\n"
2409 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
2410 " variant <id> {\n"
2411 " struct {\n"
2412 " uint27_clock_monotonic_t timestamp;\n"
2413 " } compact;\n"
2414 " struct {\n"
2415 " uint32_t id;\n"
2416 " uint64_clock_monotonic_t timestamp;\n"
2417 " } extended;\n"
2418 " } v;\n"
2419 "} align(%u);\n"
2420 "\n"
2421 "struct event_header_large {\n"
2422 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
2423 " variant <id> {\n"
2424 " struct {\n"
2425 " uint32_clock_monotonic_t timestamp;\n"
2426 " } compact;\n"
2427 " struct {\n"
2428 " uint32_t id;\n"
2429 " uint64_clock_monotonic_t timestamp;\n"
2430 " } extended;\n"
2431 " } v;\n"
2432 "} align(%u);\n\n",
2433 lttng_alignof(uint32_t) * CHAR_BIT,
2434 lttng_alignof(uint16_t) * CHAR_BIT
2435 );
2436 }
2437
2438 /*
2439 * Approximation of NTP time of day to clock monotonic correlation,
2440 * taken at start of trace.
2441 * Yes, this is only an approximation. Yes, we can (and will) do better
2442 * in future versions.
2443 * This function may return a negative offset. It may happen if the
2444 * system sets the REALTIME clock to 0 after boot.
2445 */
2446 static
2447 int64_t measure_clock_offset(void)
2448 {
2449 uint64_t monotonic_avg, monotonic[2], realtime;
2450 uint64_t tcf = trace_clock_freq();
2451 int64_t offset;
2452 struct timespec rts = { 0, 0 };
2453 unsigned long flags;
2454
2455 /* Disable interrupts to increase correlation precision. */
2456 local_irq_save(flags);
2457 monotonic[0] = trace_clock_read64();
2458 getnstimeofday(&rts);
2459 monotonic[1] = trace_clock_read64();
2460 local_irq_restore(flags);
2461
2462 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
2463 realtime = (uint64_t) rts.tv_sec * tcf;
2464 if (tcf == NSEC_PER_SEC) {
2465 realtime += rts.tv_nsec;
2466 } else {
2467 uint64_t n = rts.tv_nsec * tcf;
2468
2469 do_div(n, NSEC_PER_SEC);
2470 realtime += n;
2471 }
2472 offset = (int64_t) realtime - monotonic_avg;
2473 return offset;
2474 }
2475
2476 /*
2477 * Output metadata into this session's metadata buffers.
2478 * Must be called with sessions_mutex held.
2479 */
2480 static
2481 int _lttng_session_metadata_statedump(struct lttng_session *session)
2482 {
2483 unsigned char *uuid_c = session->uuid.b;
2484 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
2485 struct lttng_channel *chan;
2486 struct lttng_event *event;
2487 int ret = 0;
2488
2489 if (!READ_ONCE(session->active))
2490 return 0;
2491 if (session->metadata_dumped)
2492 goto skip_session;
2493
2494 snprintf(uuid_s, sizeof(uuid_s),
2495 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
2496 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
2497 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
2498 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
2499 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
2500
2501 ret = lttng_metadata_printf(session,
2502 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
2503 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
2504 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
2505 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
2506 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
2507 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
2508 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
2509 "\n"
2510 "trace {\n"
2511 " major = %u;\n"
2512 " minor = %u;\n"
2513 " uuid = \"%s\";\n"
2514 " byte_order = %s;\n"
2515 " packet.header := struct {\n"
2516 " uint32_t magic;\n"
2517 " uint8_t uuid[16];\n"
2518 " uint32_t stream_id;\n"
2519 " uint64_t stream_instance_id;\n"
2520 " };\n"
2521 "};\n\n",
2522 lttng_alignof(uint8_t) * CHAR_BIT,
2523 lttng_alignof(uint16_t) * CHAR_BIT,
2524 lttng_alignof(uint32_t) * CHAR_BIT,
2525 lttng_alignof(uint64_t) * CHAR_BIT,
2526 sizeof(unsigned long) * CHAR_BIT,
2527 lttng_alignof(unsigned long) * CHAR_BIT,
2528 CTF_SPEC_MAJOR,
2529 CTF_SPEC_MINOR,
2530 uuid_s,
2531 #if __BYTE_ORDER == __BIG_ENDIAN
2532 "be"
2533 #else
2534 "le"
2535 #endif
2536 );
2537 if (ret)
2538 goto end;
2539
2540 ret = lttng_metadata_printf(session,
2541 "env {\n"
2542 " hostname = \"%s\";\n"
2543 " domain = \"kernel\";\n"
2544 " sysname = \"%s\";\n"
2545 " kernel_release = \"%s\";\n"
2546 " kernel_version = \"%s\";\n"
2547 " tracer_name = \"lttng-modules\";\n"
2548 " tracer_major = %d;\n"
2549 " tracer_minor = %d;\n"
2550 " tracer_patchlevel = %d;\n"
2551 "};\n\n",
2552 current->nsproxy->uts_ns->name.nodename,
2553 utsname()->sysname,
2554 utsname()->release,
2555 utsname()->version,
2556 LTTNG_MODULES_MAJOR_VERSION,
2557 LTTNG_MODULES_MINOR_VERSION,
2558 LTTNG_MODULES_PATCHLEVEL_VERSION
2559 );
2560 if (ret)
2561 goto end;
2562
2563 ret = lttng_metadata_printf(session,
2564 "clock {\n"
2565 " name = \"%s\";\n",
2566 trace_clock_name()
2567 );
2568 if (ret)
2569 goto end;
2570
2571 if (!trace_clock_uuid(clock_uuid_s)) {
2572 ret = lttng_metadata_printf(session,
2573 " uuid = \"%s\";\n",
2574 clock_uuid_s
2575 );
2576 if (ret)
2577 goto end;
2578 }
2579
2580 ret = lttng_metadata_printf(session,
2581 " description = \"%s\";\n"
2582 " freq = %llu; /* Frequency, in Hz */\n"
2583 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
2584 " offset = %lld;\n"
2585 "};\n\n",
2586 trace_clock_description(),
2587 (unsigned long long) trace_clock_freq(),
2588 (long long) measure_clock_offset()
2589 );
2590 if (ret)
2591 goto end;
2592
2593 ret = lttng_metadata_printf(session,
2594 "typealias integer {\n"
2595 " size = 27; align = 1; signed = false;\n"
2596 " map = clock.%s.value;\n"
2597 "} := uint27_clock_monotonic_t;\n"
2598 "\n"
2599 "typealias integer {\n"
2600 " size = 32; align = %u; signed = false;\n"
2601 " map = clock.%s.value;\n"
2602 "} := uint32_clock_monotonic_t;\n"
2603 "\n"
2604 "typealias integer {\n"
2605 " size = 64; align = %u; signed = false;\n"
2606 " map = clock.%s.value;\n"
2607 "} := uint64_clock_monotonic_t;\n\n",
2608 trace_clock_name(),
2609 lttng_alignof(uint32_t) * CHAR_BIT,
2610 trace_clock_name(),
2611 lttng_alignof(uint64_t) * CHAR_BIT,
2612 trace_clock_name()
2613 );
2614 if (ret)
2615 goto end;
2616
2617 ret = _lttng_stream_packet_context_declare(session);
2618 if (ret)
2619 goto end;
2620
2621 ret = _lttng_event_header_declare(session);
2622 if (ret)
2623 goto end;
2624
2625 skip_session:
2626 list_for_each_entry(chan, &session->chan, list) {
2627 ret = _lttng_channel_metadata_statedump(session, chan);
2628 if (ret)
2629 goto end;
2630 }
2631
2632 list_for_each_entry(event, &session->events, list) {
2633 ret = _lttng_event_metadata_statedump(session, event->chan, event);
2634 if (ret)
2635 goto end;
2636 }
2637 session->metadata_dumped = 1;
2638 end:
2639 return ret;
2640 }
2641
2642 /**
2643 * lttng_transport_register - LTT transport registration
2644 * @transport: transport structure
2645 *
2646 * Registers a transport which can be used as output to extract the data out of
2647 * LTTng. The module calling this registration function must ensure that no
2648 * trap-inducing code will be executed by the transport functions. E.g.
2649 * vmalloc_sync_all() must be called between a vmalloc and the moment the memory
2650 * is made visible to the transport function. This registration acts as a
2651 * vmalloc_sync_all. Therefore, only if the module allocates virtual memory
2652 * after its registration must it synchronize the TLBs.
2653 */
2654 void lttng_transport_register(struct lttng_transport *transport)
2655 {
2656 /*
2657 * Make sure no page fault can be triggered by the module about to be
2658 * registered. We deal with this here so we don't have to call
2659 * vmalloc_sync_all() in each module's init.
2660 */
2661 wrapper_vmalloc_sync_all();
2662
2663 mutex_lock(&sessions_mutex);
2664 list_add_tail(&transport->node, &lttng_transport_list);
2665 mutex_unlock(&sessions_mutex);
2666 }
2667 EXPORT_SYMBOL_GPL(lttng_transport_register);
2668
2669 /**
2670 * lttng_transport_unregister - LTT transport unregistration
2671 * @transport: transport structure
2672 */
2673 void lttng_transport_unregister(struct lttng_transport *transport)
2674 {
2675 mutex_lock(&sessions_mutex);
2676 list_del(&transport->node);
2677 mutex_unlock(&sessions_mutex);
2678 }
2679 EXPORT_SYMBOL_GPL(lttng_transport_unregister);
2680
2681 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
2682
2683 enum cpuhp_state lttng_hp_prepare;
2684 enum cpuhp_state lttng_hp_online;
2685
2686 static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
2687 {
2688 struct lttng_cpuhp_node *lttng_node;
2689
2690 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2691 switch (lttng_node->component) {
2692 case LTTNG_RING_BUFFER_FRONTEND:
2693 return 0;
2694 case LTTNG_RING_BUFFER_BACKEND:
2695 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
2696 case LTTNG_RING_BUFFER_ITER:
2697 return 0;
2698 case LTTNG_CONTEXT_PERF_COUNTERS:
2699 return 0;
2700 default:
2701 return -EINVAL;
2702 }
2703 }
2704
2705 static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
2706 {
2707 struct lttng_cpuhp_node *lttng_node;
2708
2709 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2710 switch (lttng_node->component) {
2711 case LTTNG_RING_BUFFER_FRONTEND:
2712 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
2713 case LTTNG_RING_BUFFER_BACKEND:
2714 return 0;
2715 case LTTNG_RING_BUFFER_ITER:
2716 return 0;
2717 case LTTNG_CONTEXT_PERF_COUNTERS:
2718 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
2719 default:
2720 return -EINVAL;
2721 }
2722 }
2723
2724 static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
2725 {
2726 struct lttng_cpuhp_node *lttng_node;
2727
2728 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2729 switch (lttng_node->component) {
2730 case LTTNG_RING_BUFFER_FRONTEND:
2731 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
2732 case LTTNG_RING_BUFFER_BACKEND:
2733 return 0;
2734 case LTTNG_RING_BUFFER_ITER:
2735 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
2736 case LTTNG_CONTEXT_PERF_COUNTERS:
2737 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
2738 default:
2739 return -EINVAL;
2740 }
2741 }
2742
2743 static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
2744 {
2745 struct lttng_cpuhp_node *lttng_node;
2746
2747 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2748 switch (lttng_node->component) {
2749 case LTTNG_RING_BUFFER_FRONTEND:
2750 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
2751 case LTTNG_RING_BUFFER_BACKEND:
2752 return 0;
2753 case LTTNG_RING_BUFFER_ITER:
2754 return 0;
2755 case LTTNG_CONTEXT_PERF_COUNTERS:
2756 return 0;
2757 default:
2758 return -EINVAL;
2759 }
2760 }
2761
2762 static int __init lttng_init_cpu_hotplug(void)
2763 {
2764 int ret;
2765
2766 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
2767 lttng_hotplug_prepare,
2768 lttng_hotplug_dead);
2769 if (ret < 0) {
2770 return ret;
2771 }
2772 lttng_hp_prepare = ret;
2773 lttng_rb_set_hp_prepare(ret);
2774
2775 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
2776 lttng_hotplug_online,
2777 lttng_hotplug_offline);
2778 if (ret < 0) {
2779 cpuhp_remove_multi_state(lttng_hp_prepare);
2780 lttng_hp_prepare = 0;
2781 return ret;
2782 }
2783 lttng_hp_online = ret;
2784 lttng_rb_set_hp_online(ret);
2785
2786 return 0;
2787 }
2788
2789 static void __exit lttng_exit_cpu_hotplug(void)
2790 {
2791 lttng_rb_set_hp_online(0);
2792 cpuhp_remove_multi_state(lttng_hp_online);
2793 lttng_rb_set_hp_prepare(0);
2794 cpuhp_remove_multi_state(lttng_hp_prepare);
2795 }
2796
2797 #else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
2798 static int lttng_init_cpu_hotplug(void)
2799 {
2800 return 0;
2801 }
2802 static void lttng_exit_cpu_hotplug(void)
2803 {
2804 }
2805 #endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
2806
2807
2808 static int __init lttng_events_init(void)
2809 {
2810 int ret;
2811
2812 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
2813 if (ret)
2814 return ret;
2815 ret = wrapper_get_pfnblock_flags_mask_init();
2816 if (ret)
2817 return ret;
2818 ret = wrapper_get_pageblock_flags_mask_init();
2819 if (ret)
2820 return ret;
2821 ret = lttng_probes_init();
2822 if (ret)
2823 return ret;
2824 ret = lttng_context_init();
2825 if (ret)
2826 return ret;
2827 ret = lttng_tracepoint_init();
2828 if (ret)
2829 goto error_tp;
2830 event_cache = KMEM_CACHE(lttng_event, 0);
2831 if (!event_cache) {
2832 ret = -ENOMEM;
2833 goto error_kmem;
2834 }
2835 ret = lttng_abi_init();
2836 if (ret)
2837 goto error_abi;
2838 ret = lttng_logger_init();
2839 if (ret)
2840 goto error_logger;
2841 ret = lttng_init_cpu_hotplug();
2842 if (ret)
2843 goto error_hotplug;
2844 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
2845 __stringify(LTTNG_MODULES_MAJOR_VERSION),
2846 __stringify(LTTNG_MODULES_MINOR_VERSION),
2847 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
2848 LTTNG_MODULES_EXTRAVERSION,
2849 LTTNG_VERSION_NAME,
2850 #ifdef LTTNG_EXTRA_VERSION_GIT
2851 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
2852 #else
2853 "",
2854 #endif
2855 #ifdef LTTNG_EXTRA_VERSION_NAME
2856 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
2857 #else
2858 "");
2859 #endif
2860 return 0;
2861
2862 error_hotplug:
2863 lttng_logger_exit();
2864 error_logger:
2865 lttng_abi_exit();
2866 error_abi:
2867 kmem_cache_destroy(event_cache);
2868 error_kmem:
2869 lttng_tracepoint_exit();
2870 error_tp:
2871 lttng_context_exit();
2872 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
2873 __stringify(LTTNG_MODULES_MAJOR_VERSION),
2874 __stringify(LTTNG_MODULES_MINOR_VERSION),
2875 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
2876 LTTNG_MODULES_EXTRAVERSION,
2877 LTTNG_VERSION_NAME,
2878 #ifdef LTTNG_EXTRA_VERSION_GIT
2879 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
2880 #else
2881 "",
2882 #endif
2883 #ifdef LTTNG_EXTRA_VERSION_NAME
2884 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
2885 #else
2886 "");
2887 #endif
2888 return ret;
2889 }
2890
2891 module_init(lttng_events_init);
2892
2893 static void __exit lttng_events_exit(void)
2894 {
2895 struct lttng_session *session, *tmpsession;
2896
2897 lttng_exit_cpu_hotplug();
2898 lttng_logger_exit();
2899 lttng_abi_exit();
2900 list_for_each_entry_safe(session, tmpsession, &sessions, list)
2901 lttng_session_destroy(session);
2902 kmem_cache_destroy(event_cache);
2903 lttng_tracepoint_exit();
2904 lttng_context_exit();
2905 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
2906 __stringify(LTTNG_MODULES_MAJOR_VERSION),
2907 __stringify(LTTNG_MODULES_MINOR_VERSION),
2908 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
2909 LTTNG_MODULES_EXTRAVERSION,
2910 LTTNG_VERSION_NAME,
2911 #ifdef LTTNG_EXTRA_VERSION_GIT
2912 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
2913 #else
2914 "",
2915 #endif
2916 #ifdef LTTNG_EXTRA_VERSION_NAME
2917 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
2918 #else
2919 "");
2920 #endif
2921 }
2922
2923 module_exit(lttng_events_exit);
2924
2925 #include "extra_version/patches.i"
2926 #ifdef LTTNG_EXTRA_VERSION_GIT
2927 MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
2928 #endif
2929 #ifdef LTTNG_EXTRA_VERSION_NAME
2930 MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
2931 #endif
2932 MODULE_LICENSE("GPL and additional rights");
2933 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
2934 MODULE_DESCRIPTION("LTTng tracer");
2935 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
2936 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
2937 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
2938 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
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