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Cleanup: notifier syscalls: Remove useless zero-init of zeroed memory
[lttng-modules.git] / src / lttng-events.c
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1/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
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/uaccess.h>
28#include <linux/vmalloc.h>
29#include <linux/dmi.h>
30
31#include <wrapper/compiler_attributes.h>
32#include <wrapper/uuid.h>
33#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
34#include <wrapper/random.h>
35#include <wrapper/tracepoint.h>
36#include <wrapper/list.h>
37#include <wrapper/types.h>
38#include <lttng/kernel-version.h>
39#include <lttng/events.h>
40#include <lttng/events-internal.h>
41#include <lttng/lttng-bytecode.h>
42#include <lttng/tracer.h>
43#include <lttng/event-notifier-notification.h>
44#include <lttng/abi-old.h>
45#include <lttng/endian.h>
46#include <lttng/string-utils.h>
47#include <lttng/utils.h>
48#include <ringbuffer/backend.h>
49#include <ringbuffer/frontend.h>
50#include <wrapper/time.h>
51
52#define METADATA_CACHE_DEFAULT_SIZE 4096
53
54static LIST_HEAD(sessions);
55static LIST_HEAD(event_notifier_groups);
56static LIST_HEAD(lttng_transport_list);
57static LIST_HEAD(lttng_counter_transport_list);
58/*
59 * Protect the sessions and metadata caches.
60 */
61static DEFINE_MUTEX(sessions_mutex);
62static struct kmem_cache *event_recorder_cache;
63static struct kmem_cache *event_recorder_private_cache;
64static struct kmem_cache *event_notifier_cache;
65static struct kmem_cache *event_notifier_private_cache;
66
67static void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session);
68static void lttng_session_sync_event_enablers(struct lttng_kernel_session *session);
69static void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group);
70static void lttng_event_enabler_sync(struct lttng_event_enabler_common *event_enabler);
71
72static void _lttng_event_destroy(struct lttng_kernel_event_common *event);
73static void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan);
74static int _lttng_event_unregister(struct lttng_kernel_event_recorder *event);
75static int _lttng_event_notifier_unregister(struct lttng_kernel_event_notifier *event_notifier);
76static
77int _lttng_event_metadata_statedump(struct lttng_kernel_session *session,
78 struct lttng_kernel_channel_buffer *chan,
79 struct lttng_kernel_event_recorder *event);
80static
81int _lttng_session_metadata_statedump(struct lttng_kernel_session *session);
82static
83void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
84static
85int _lttng_type_statedump(struct lttng_kernel_session *session,
86 const struct lttng_kernel_type_common *type,
87 enum lttng_kernel_string_encoding parent_encoding,
88 size_t nesting);
89static
90int _lttng_field_statedump(struct lttng_kernel_session *session,
91 const struct lttng_kernel_event_field *field,
92 size_t nesting, const char **prev_field_name_p);
93
94void synchronize_trace(void)
95{
96#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,1,0) || \
97 LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
98 synchronize_rcu();
99#else
100 synchronize_sched();
101#endif
102
103#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0))
104#ifdef CONFIG_PREEMPT_RT_FULL
105 synchronize_rcu();
106#endif
107#else /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
108#ifdef CONFIG_PREEMPT_RT
109 synchronize_rcu();
110#endif
111#endif /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
112}
113
114void lttng_lock_sessions(void)
115{
116 mutex_lock(&sessions_mutex);
117}
118
119void lttng_unlock_sessions(void)
120{
121 mutex_unlock(&sessions_mutex);
122}
123
124static struct lttng_transport *lttng_transport_find(const char *name)
125{
126 struct lttng_transport *transport;
127
128 list_for_each_entry(transport, &lttng_transport_list, node) {
129 if (!strcmp(transport->name, name))
130 return transport;
131 }
132 return NULL;
133}
134
135/*
136 * Called with sessions lock held.
137 */
138int lttng_session_active(void)
139{
140 struct lttng_kernel_session_private *iter;
141
142 list_for_each_entry(iter, &sessions, list) {
143 if (iter->pub->active)
144 return 1;
145 }
146 return 0;
147}
148
149struct lttng_kernel_session *lttng_session_create(void)
150{
151 struct lttng_kernel_session *session;
152 struct lttng_kernel_session_private *session_priv;
153 struct lttng_metadata_cache *metadata_cache;
154 int i;
155
156 mutex_lock(&sessions_mutex);
157 session = lttng_kvzalloc(sizeof(*session), GFP_KERNEL);
158 if (!session)
159 goto err;
160 session_priv = lttng_kvzalloc(sizeof(*session_priv), GFP_KERNEL);
161 if (!session_priv)
162 goto err_free_session;
163 session->priv = session_priv;
164 session_priv->pub = session;
165
166 INIT_LIST_HEAD(&session_priv->chan);
167 INIT_LIST_HEAD(&session_priv->events);
168 lttng_guid_gen(&session_priv->uuid);
169
170 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
171 GFP_KERNEL);
172 if (!metadata_cache)
173 goto err_free_session_private;
174 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
175 if (!metadata_cache->data)
176 goto err_free_cache;
177 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
178 kref_init(&metadata_cache->refcount);
179 mutex_init(&metadata_cache->lock);
180 session_priv->metadata_cache = metadata_cache;
181 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
182 memcpy(&metadata_cache->uuid, &session_priv->uuid,
183 sizeof(metadata_cache->uuid));
184 INIT_LIST_HEAD(&session_priv->enablers_head);
185 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
186 INIT_HLIST_HEAD(&session_priv->events_ht.table[i]);
187 list_add(&session_priv->list, &sessions);
188
189 if (lttng_id_tracker_init(&session->pid_tracker, session, TRACKER_PID))
190 goto tracker_alloc_error;
191 if (lttng_id_tracker_init(&session->vpid_tracker, session, TRACKER_VPID))
192 goto tracker_alloc_error;
193 if (lttng_id_tracker_init(&session->uid_tracker, session, TRACKER_UID))
194 goto tracker_alloc_error;
195 if (lttng_id_tracker_init(&session->vuid_tracker, session, TRACKER_VUID))
196 goto tracker_alloc_error;
197 if (lttng_id_tracker_init(&session->gid_tracker, session, TRACKER_GID))
198 goto tracker_alloc_error;
199 if (lttng_id_tracker_init(&session->vgid_tracker, session, TRACKER_VGID))
200 goto tracker_alloc_error;
201
202 mutex_unlock(&sessions_mutex);
203
204 return session;
205
206tracker_alloc_error:
207 lttng_id_tracker_fini(&session->pid_tracker);
208 lttng_id_tracker_fini(&session->vpid_tracker);
209 lttng_id_tracker_fini(&session->uid_tracker);
210 lttng_id_tracker_fini(&session->vuid_tracker);
211 lttng_id_tracker_fini(&session->gid_tracker);
212 lttng_id_tracker_fini(&session->vgid_tracker);
213err_free_cache:
214 kfree(metadata_cache);
215err_free_session_private:
216 lttng_kvfree(session_priv);
217err_free_session:
218 lttng_kvfree(session);
219err:
220 mutex_unlock(&sessions_mutex);
221 return NULL;
222}
223
224static
225struct lttng_counter_transport *lttng_counter_transport_find(const char *name)
226{
227 struct lttng_counter_transport *transport;
228
229 list_for_each_entry(transport, &lttng_counter_transport_list, node) {
230 if (!strcmp(transport->name, name))
231 return transport;
232 }
233 return NULL;
234}
235
236struct lttng_counter *lttng_kernel_counter_create(
237 const char *counter_transport_name,
238 size_t number_dimensions, const size_t *dimensions_sizes)
239{
240 struct lttng_counter *counter = NULL;
241 struct lttng_counter_transport *counter_transport = NULL;
242
243 counter_transport = lttng_counter_transport_find(counter_transport_name);
244 if (!counter_transport) {
245 printk(KERN_WARNING "LTTng: counter transport %s not found.\n",
246 counter_transport_name);
247 goto notransport;
248 }
249 if (!try_module_get(counter_transport->owner)) {
250 printk(KERN_WARNING "LTTng: Can't lock counter transport module.\n");
251 goto notransport;
252 }
253
254 counter = lttng_kvzalloc(sizeof(struct lttng_counter), GFP_KERNEL);
255 if (!counter)
256 goto nomem;
257
258 /* Create event notifier error counter. */
259 counter->ops = &counter_transport->ops;
260 counter->transport = counter_transport;
261
262 counter->counter = counter->ops->counter_create(
263 number_dimensions, dimensions_sizes, 0);
264 if (!counter->counter) {
265 goto create_error;
266 }
267
268 return counter;
269
270create_error:
271 lttng_kvfree(counter);
272nomem:
273 if (counter_transport)
274 module_put(counter_transport->owner);
275notransport:
276 return NULL;
277}
278
279struct lttng_event_notifier_group *lttng_event_notifier_group_create(void)
280{
281 struct lttng_transport *transport = NULL;
282 struct lttng_event_notifier_group *event_notifier_group;
283 const char *transport_name = "relay-event-notifier";
284 size_t subbuf_size = 4096; //TODO
285 size_t num_subbuf = 16; //TODO
286 unsigned int switch_timer_interval = 0;
287 unsigned int read_timer_interval = 0;
288 int i;
289
290 mutex_lock(&sessions_mutex);
291
292 transport = lttng_transport_find(transport_name);
293 if (!transport) {
294 printk(KERN_WARNING "LTTng: transport %s not found\n",
295 transport_name);
296 goto notransport;
297 }
298 if (!try_module_get(transport->owner)) {
299 printk(KERN_WARNING "LTTng: Can't lock transport %s module.\n",
300 transport_name);
301 goto notransport;
302 }
303
304 event_notifier_group = lttng_kvzalloc(sizeof(struct lttng_event_notifier_group),
305 GFP_KERNEL);
306 if (!event_notifier_group)
307 goto nomem;
308
309 /*
310 * Initialize the ring buffer used to store event notifier
311 * notifications.
312 */
313 event_notifier_group->ops = &transport->ops;
314 event_notifier_group->chan = transport->ops.priv->channel_create(
315 transport_name, event_notifier_group, NULL,
316 subbuf_size, num_subbuf, switch_timer_interval,
317 read_timer_interval);
318 if (!event_notifier_group->chan)
319 goto create_error;
320
321 event_notifier_group->transport = transport;
322
323 INIT_LIST_HEAD(&event_notifier_group->enablers_head);
324 INIT_LIST_HEAD(&event_notifier_group->event_notifiers_head);
325 for (i = 0; i < LTTNG_EVENT_NOTIFIER_HT_SIZE; i++)
326 INIT_HLIST_HEAD(&event_notifier_group->event_notifiers_ht.table[i]);
327
328 list_add(&event_notifier_group->node, &event_notifier_groups);
329
330 mutex_unlock(&sessions_mutex);
331
332 return event_notifier_group;
333
334create_error:
335 lttng_kvfree(event_notifier_group);
336nomem:
337 if (transport)
338 module_put(transport->owner);
339notransport:
340 mutex_unlock(&sessions_mutex);
341 return NULL;
342}
343
344void metadata_cache_destroy(struct kref *kref)
345{
346 struct lttng_metadata_cache *cache =
347 container_of(kref, struct lttng_metadata_cache, refcount);
348 vfree(cache->data);
349 kfree(cache);
350}
351
352void lttng_session_destroy(struct lttng_kernel_session *session)
353{
354 struct lttng_kernel_channel_buffer_private *chan_priv, *tmpchan_priv;
355 struct lttng_kernel_event_recorder_private *event_recorder_priv, *tmpevent_recorder_priv;
356 struct lttng_metadata_stream *metadata_stream;
357 struct lttng_event_recorder_enabler *event_recorder_enabler, *tmp_event_recorder_enabler;
358 int ret;
359
360 mutex_lock(&sessions_mutex);
361 WRITE_ONCE(session->active, 0);
362 list_for_each_entry(chan_priv, &session->priv->chan, node) {
363 ret = lttng_syscalls_unregister_channel(chan_priv->pub);
364 WARN_ON(ret);
365 }
366 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
367 ret = _lttng_event_unregister(event_recorder_priv->pub);
368 WARN_ON(ret);
369 }
370 synchronize_trace(); /* Wait for in-flight events to complete */
371 list_for_each_entry(chan_priv, &session->priv->chan, node) {
372 ret = lttng_syscalls_destroy_event(chan_priv->pub);
373 WARN_ON(ret);
374 }
375 list_for_each_entry_safe(event_recorder_enabler, tmp_event_recorder_enabler,
376 &session->priv->enablers_head, node)
377 lttng_event_enabler_destroy(&event_recorder_enabler->parent);
378 list_for_each_entry_safe(event_recorder_priv, tmpevent_recorder_priv, &session->priv->events, node)
379 _lttng_event_destroy(&event_recorder_priv->pub->parent);
380 list_for_each_entry_safe(chan_priv, tmpchan_priv, &session->priv->chan, node) {
381 BUG_ON(chan_priv->channel_type == METADATA_CHANNEL);
382 _lttng_channel_destroy(chan_priv->pub);
383 }
384 mutex_lock(&session->priv->metadata_cache->lock);
385 list_for_each_entry(metadata_stream, &session->priv->metadata_cache->metadata_stream, list)
386 _lttng_metadata_channel_hangup(metadata_stream);
387 mutex_unlock(&session->priv->metadata_cache->lock);
388 lttng_id_tracker_fini(&session->pid_tracker);
389 lttng_id_tracker_fini(&session->vpid_tracker);
390 lttng_id_tracker_fini(&session->uid_tracker);
391 lttng_id_tracker_fini(&session->vuid_tracker);
392 lttng_id_tracker_fini(&session->gid_tracker);
393 lttng_id_tracker_fini(&session->vgid_tracker);
394 kref_put(&session->priv->metadata_cache->refcount, metadata_cache_destroy);
395 list_del(&session->priv->list);
396 mutex_unlock(&sessions_mutex);
397 lttng_kvfree(session->priv);
398 lttng_kvfree(session);
399}
400
401void lttng_event_notifier_group_destroy(
402 struct lttng_event_notifier_group *event_notifier_group)
403{
404 struct lttng_event_notifier_enabler *event_notifier_enabler, *tmp_event_notifier_enabler;
405 struct lttng_kernel_event_notifier_private *event_notifier_priv, *tmpevent_notifier_priv;
406 int ret;
407
408 if (!event_notifier_group)
409 return;
410
411 mutex_lock(&sessions_mutex);
412
413 ret = lttng_syscalls_unregister_event_notifier_group(event_notifier_group);
414 WARN_ON(ret);
415
416 list_for_each_entry_safe(event_notifier_priv, tmpevent_notifier_priv,
417 &event_notifier_group->event_notifiers_head, node) {
418 ret = _lttng_event_notifier_unregister(event_notifier_priv->pub);
419 WARN_ON(ret);
420 }
421
422 /* Wait for in-flight event notifier to complete */
423 synchronize_trace();
424
425 irq_work_sync(&event_notifier_group->wakeup_pending);
426
427 kfree(event_notifier_group->syscall_table.sc_filter);
428
429 list_for_each_entry_safe(event_notifier_enabler, tmp_event_notifier_enabler,
430 &event_notifier_group->enablers_head, node)
431 lttng_event_enabler_destroy(&event_notifier_enabler->parent);
432
433 list_for_each_entry_safe(event_notifier_priv, tmpevent_notifier_priv,
434 &event_notifier_group->event_notifiers_head, node)
435 _lttng_event_destroy(&event_notifier_priv->pub->parent);
436
437 if (event_notifier_group->error_counter) {
438 struct lttng_counter *error_counter = event_notifier_group->error_counter;
439
440 error_counter->ops->counter_destroy(error_counter->counter);
441 module_put(error_counter->transport->owner);
442 lttng_kvfree(error_counter);
443 event_notifier_group->error_counter = NULL;
444 }
445
446 event_notifier_group->ops->priv->channel_destroy(event_notifier_group->chan);
447 module_put(event_notifier_group->transport->owner);
448 list_del(&event_notifier_group->node);
449
450 mutex_unlock(&sessions_mutex);
451 lttng_kvfree(event_notifier_group);
452}
453
454int lttng_session_statedump(struct lttng_kernel_session *session)
455{
456 int ret;
457
458 mutex_lock(&sessions_mutex);
459 ret = lttng_statedump_start(session);
460 mutex_unlock(&sessions_mutex);
461 return ret;
462}
463
464int lttng_session_enable(struct lttng_kernel_session *session)
465{
466 int ret = 0;
467 struct lttng_kernel_channel_buffer_private *chan_priv;
468
469 mutex_lock(&sessions_mutex);
470 if (session->active) {
471 ret = -EBUSY;
472 goto end;
473 }
474
475 /* Set transient enabler state to "enabled" */
476 session->priv->tstate = 1;
477
478 /* We need to sync enablers with session before activation. */
479 lttng_session_sync_event_enablers(session);
480
481 /*
482 * Snapshot the number of events per channel to know the type of header
483 * we need to use.
484 */
485 list_for_each_entry(chan_priv, &session->priv->chan, node) {
486 if (chan_priv->header_type)
487 continue; /* don't change it if session stop/restart */
488 if (chan_priv->free_event_id < 31)
489 chan_priv->header_type = 1; /* compact */
490 else
491 chan_priv->header_type = 2; /* large */
492 }
493
494 /* Clear each stream's quiescent state. */
495 list_for_each_entry(chan_priv, &session->priv->chan, node) {
496 if (chan_priv->channel_type != METADATA_CHANNEL)
497 lib_ring_buffer_clear_quiescent_channel(chan_priv->rb_chan);
498 }
499
500 WRITE_ONCE(session->active, 1);
501 WRITE_ONCE(session->priv->been_active, 1);
502 ret = _lttng_session_metadata_statedump(session);
503 if (ret) {
504 WRITE_ONCE(session->active, 0);
505 goto end;
506 }
507 ret = lttng_statedump_start(session);
508 if (ret)
509 WRITE_ONCE(session->active, 0);
510end:
511 mutex_unlock(&sessions_mutex);
512 return ret;
513}
514
515int lttng_session_disable(struct lttng_kernel_session *session)
516{
517 int ret = 0;
518 struct lttng_kernel_channel_buffer_private *chan_priv;
519
520 mutex_lock(&sessions_mutex);
521 if (!session->active) {
522 ret = -EBUSY;
523 goto end;
524 }
525 WRITE_ONCE(session->active, 0);
526
527 /* Set transient enabler state to "disabled" */
528 session->priv->tstate = 0;
529 lttng_session_sync_event_enablers(session);
530
531 /* Set each stream's quiescent state. */
532 list_for_each_entry(chan_priv, &session->priv->chan, node) {
533 if (chan_priv->channel_type != METADATA_CHANNEL)
534 lib_ring_buffer_set_quiescent_channel(chan_priv->rb_chan);
535 }
536end:
537 mutex_unlock(&sessions_mutex);
538 return ret;
539}
540
541int lttng_session_metadata_regenerate(struct lttng_kernel_session *session)
542{
543 int ret = 0;
544 struct lttng_kernel_channel_buffer_private *chan_priv;
545 struct lttng_kernel_event_recorder_private *event_recorder_priv;
546 struct lttng_metadata_cache *cache = session->priv->metadata_cache;
547 struct lttng_metadata_stream *stream;
548
549 mutex_lock(&sessions_mutex);
550 if (!session->active) {
551 ret = -EBUSY;
552 goto end;
553 }
554
555 mutex_lock(&cache->lock);
556 memset(cache->data, 0, cache->cache_alloc);
557 cache->metadata_written = 0;
558 cache->version++;
559 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list) {
560 stream->metadata_out = 0;
561 stream->metadata_in = 0;
562 }
563 mutex_unlock(&cache->lock);
564
565 session->priv->metadata_dumped = 0;
566 list_for_each_entry(chan_priv, &session->priv->chan, node) {
567 chan_priv->metadata_dumped = 0;
568 }
569
570 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
571 event_recorder_priv->metadata_dumped = 0;
572 }
573
574 ret = _lttng_session_metadata_statedump(session);
575
576end:
577 mutex_unlock(&sessions_mutex);
578 return ret;
579}
580
581int lttng_channel_enable(struct lttng_kernel_channel_buffer *channel)
582{
583 int ret = 0;
584
585 mutex_lock(&sessions_mutex);
586 if (channel->priv->channel_type == METADATA_CHANNEL) {
587 ret = -EPERM;
588 goto end;
589 }
590 if (channel->parent.enabled) {
591 ret = -EEXIST;
592 goto end;
593 }
594 /* Set transient enabler state to "enabled" */
595 channel->priv->parent.tstate = 1;
596 lttng_session_sync_event_enablers(channel->parent.session);
597 /* Set atomically the state to "enabled" */
598 WRITE_ONCE(channel->parent.enabled, 1);
599end:
600 mutex_unlock(&sessions_mutex);
601 return ret;
602}
603
604int lttng_channel_disable(struct lttng_kernel_channel_buffer *channel)
605{
606 int ret = 0;
607
608 mutex_lock(&sessions_mutex);
609 if (channel->priv->channel_type == METADATA_CHANNEL) {
610 ret = -EPERM;
611 goto end;
612 }
613 if (!channel->parent.enabled) {
614 ret = -EEXIST;
615 goto end;
616 }
617 /* Set atomically the state to "disabled" */
618 WRITE_ONCE(channel->parent.enabled, 0);
619 /* Set transient enabler state to "enabled" */
620 channel->priv->parent.tstate = 0;
621 lttng_session_sync_event_enablers(channel->parent.session);
622end:
623 mutex_unlock(&sessions_mutex);
624 return ret;
625}
626
627int lttng_event_enable(struct lttng_kernel_event_common *event)
628{
629 int ret = 0;
630
631 mutex_lock(&sessions_mutex);
632 switch (event->type) {
633 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
634 {
635 struct lttng_kernel_event_recorder *event_recorder =
636 container_of(event, struct lttng_kernel_event_recorder, parent);
637
638 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
639 ret = -EPERM;
640 goto end;
641 }
642 break;
643 }
644 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
645 switch (event->priv->instrumentation) {
646 case LTTNG_KERNEL_ABI_KRETPROBE:
647 ret = -EINVAL;
648 goto end;
649 default:
650 break;
651 }
652 break;
653 default:
654 break;
655 }
656
657 if (event->enabled) {
658 ret = -EEXIST;
659 goto end;
660 }
661 switch (event->priv->instrumentation) {
662 case LTTNG_KERNEL_ABI_TRACEPOINT:
663 lttng_fallthrough;
664 case LTTNG_KERNEL_ABI_SYSCALL:
665 ret = -EINVAL;
666 break;
667
668 case LTTNG_KERNEL_ABI_KPROBE:
669 lttng_fallthrough;
670 case LTTNG_KERNEL_ABI_UPROBE:
671 WRITE_ONCE(event->enabled, 1);
672 break;
673
674 case LTTNG_KERNEL_ABI_KRETPROBE:
675 ret = lttng_kretprobes_event_enable_state(event, 1);
676 break;
677
678 case LTTNG_KERNEL_ABI_FUNCTION:
679 lttng_fallthrough;
680 case LTTNG_KERNEL_ABI_NOOP:
681 lttng_fallthrough;
682 default:
683 WARN_ON_ONCE(1);
684 ret = -EINVAL;
685 }
686end:
687 mutex_unlock(&sessions_mutex);
688 return ret;
689}
690
691int lttng_event_disable(struct lttng_kernel_event_common *event)
692{
693 int ret = 0;
694
695 mutex_lock(&sessions_mutex);
696 switch (event->type) {
697 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
698 {
699 struct lttng_kernel_event_recorder *event_recorder =
700 container_of(event, struct lttng_kernel_event_recorder, parent);
701
702 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
703 ret = -EPERM;
704 goto end;
705 }
706 break;
707 }
708 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
709 switch (event->priv->instrumentation) {
710 case LTTNG_KERNEL_ABI_KRETPROBE:
711 ret = -EINVAL;
712 goto end;
713 default:
714 break;
715 }
716 break;
717 default:
718 break;
719 }
720
721 if (!event->enabled) {
722 ret = -EEXIST;
723 goto end;
724 }
725 switch (event->priv->instrumentation) {
726 case LTTNG_KERNEL_ABI_TRACEPOINT:
727 lttng_fallthrough;
728 case LTTNG_KERNEL_ABI_SYSCALL:
729 ret = -EINVAL;
730 break;
731
732 case LTTNG_KERNEL_ABI_KPROBE:
733 lttng_fallthrough;
734 case LTTNG_KERNEL_ABI_UPROBE:
735 WRITE_ONCE(event->enabled, 0);
736 break;
737
738 case LTTNG_KERNEL_ABI_KRETPROBE:
739 ret = lttng_kretprobes_event_enable_state(event, 0);
740 break;
741
742 case LTTNG_KERNEL_ABI_FUNCTION:
743 lttng_fallthrough;
744 case LTTNG_KERNEL_ABI_NOOP:
745 lttng_fallthrough;
746 default:
747 WARN_ON_ONCE(1);
748 ret = -EINVAL;
749 }
750end:
751 mutex_unlock(&sessions_mutex);
752 return ret;
753}
754
755struct lttng_kernel_channel_buffer *lttng_channel_create(struct lttng_kernel_session *session,
756 const char *transport_name,
757 void *buf_addr,
758 size_t subbuf_size, size_t num_subbuf,
759 unsigned int switch_timer_interval,
760 unsigned int read_timer_interval,
761 enum channel_type channel_type)
762{
763 struct lttng_kernel_channel_buffer *chan;
764 struct lttng_kernel_channel_buffer_private *chan_priv;
765 struct lttng_transport *transport = NULL;
766
767 mutex_lock(&sessions_mutex);
768 if (session->priv->been_active && channel_type != METADATA_CHANNEL)
769 goto active; /* Refuse to add channel to active session */
770 transport = lttng_transport_find(transport_name);
771 if (!transport) {
772 printk(KERN_WARNING "LTTng: transport %s not found\n",
773 transport_name);
774 goto notransport;
775 }
776 if (!try_module_get(transport->owner)) {
777 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
778 goto notransport;
779 }
780 chan = kzalloc(sizeof(struct lttng_kernel_channel_buffer), GFP_KERNEL);
781 if (!chan)
782 goto nomem;
783 chan_priv = kzalloc(sizeof(struct lttng_kernel_channel_buffer_private), GFP_KERNEL);
784 if (!chan_priv)
785 goto nomem_priv;
786 chan->priv = chan_priv;
787 chan_priv->pub = chan;
788 chan->parent.type = LTTNG_KERNEL_CHANNEL_TYPE_BUFFER;
789 chan->parent.session = session;
790 chan->priv->id = session->priv->free_chan_id++;
791 chan->ops = &transport->ops;
792 /*
793 * Note: the channel creation op already writes into the packet
794 * headers. Therefore the "chan" information used as input
795 * should be already accessible.
796 */
797 chan->priv->rb_chan = transport->ops.priv->channel_create(transport_name,
798 chan, buf_addr, subbuf_size, num_subbuf,
799 switch_timer_interval, read_timer_interval);
800 if (!chan->priv->rb_chan)
801 goto create_error;
802 chan->priv->parent.tstate = 1;
803 chan->parent.enabled = 1;
804 chan->priv->transport = transport;
805 chan->priv->channel_type = channel_type;
806 list_add(&chan->priv->node, &session->priv->chan);
807 mutex_unlock(&sessions_mutex);
808 return chan;
809
810create_error:
811 kfree(chan_priv);
812nomem_priv:
813 kfree(chan);
814nomem:
815 if (transport)
816 module_put(transport->owner);
817notransport:
818active:
819 mutex_unlock(&sessions_mutex);
820 return NULL;
821}
822
823/*
824 * Only used internally at session destruction for per-cpu channels, and
825 * when metadata channel is released.
826 * Needs to be called with sessions mutex held.
827 */
828static
829void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan)
830{
831 chan->ops->priv->channel_destroy(chan->priv->rb_chan);
832 module_put(chan->priv->transport->owner);
833 list_del(&chan->priv->node);
834 lttng_kernel_destroy_context(chan->priv->ctx);
835 kfree(chan->priv);
836 kfree(chan);
837}
838
839void lttng_metadata_channel_destroy(struct lttng_kernel_channel_buffer *chan)
840{
841 BUG_ON(chan->priv->channel_type != METADATA_CHANNEL);
842
843 /* Protect the metadata cache with the sessions_mutex. */
844 mutex_lock(&sessions_mutex);
845 _lttng_channel_destroy(chan);
846 mutex_unlock(&sessions_mutex);
847}
848EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
849
850static
851void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
852{
853 stream->finalized = 1;
854 wake_up_interruptible(&stream->read_wait);
855}
856
857
858/*
859 * Supports event creation while tracing session is active.
860 * Needs to be called with sessions mutex held.
861 */
862struct lttng_kernel_event_recorder *_lttng_kernel_event_recorder_create(struct lttng_event_recorder_enabler *event_enabler,
863 const struct lttng_kernel_event_desc *event_desc)
864{
865 struct lttng_kernel_channel_buffer *chan = event_enabler->chan;
866 struct lttng_kernel_abi_event *event_param = &event_enabler->parent.event_param;
867 enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
868 struct lttng_kernel_session *session = chan->parent.session;
869 struct lttng_kernel_event_recorder *event_recorder;
870 struct lttng_kernel_event_recorder_private *event_recorder_priv;
871 const char *event_name;
872 struct hlist_head *head;
873 int ret;
874
875 if (chan->priv->free_event_id == -1U) {
876 ret = -EMFILE;
877 goto full;
878 }
879
880 switch (itype) {
881 case LTTNG_KERNEL_ABI_TRACEPOINT:
882 event_name = event_desc->event_name;
883 break;
884
885 case LTTNG_KERNEL_ABI_KPROBE:
886 lttng_fallthrough;
887 case LTTNG_KERNEL_ABI_UPROBE:
888 lttng_fallthrough;
889 case LTTNG_KERNEL_ABI_KRETPROBE:
890 lttng_fallthrough;
891 case LTTNG_KERNEL_ABI_SYSCALL:
892 event_name = event_param->name;
893 break;
894
895 case LTTNG_KERNEL_ABI_FUNCTION:
896 lttng_fallthrough;
897 case LTTNG_KERNEL_ABI_NOOP:
898 lttng_fallthrough;
899 default:
900 WARN_ON_ONCE(1);
901 ret = -EINVAL;
902 goto type_error;
903 }
904
905 head = utils_borrow_hash_table_bucket(session->priv->events_ht.table,
906 LTTNG_EVENT_HT_SIZE, event_name);
907 lttng_hlist_for_each_entry(event_recorder_priv, head, hlist) {
908 WARN_ON_ONCE(!event_recorder_priv->parent.desc);
909 if (!strncmp(event_recorder_priv->parent.desc->event_name, event_name,
910 LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
911 && chan == event_recorder_priv->pub->chan) {
912 ret = -EEXIST;
913 goto exist;
914 }
915 }
916
917 event_recorder = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
918 if (!event_recorder) {
919 ret = -ENOMEM;
920 goto cache_error;
921 }
922 event_recorder_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
923 if (!event_recorder_priv) {
924 ret = -ENOMEM;
925 goto cache_private_error;
926 }
927 event_recorder_priv->pub = event_recorder;
928 event_recorder_priv->parent.pub = &event_recorder->parent;
929 event_recorder->priv = event_recorder_priv;
930 event_recorder->parent.priv = &event_recorder_priv->parent;
931 event_recorder->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
932
933 event_recorder->parent.run_filter = lttng_kernel_interpret_event_filter;
934 event_recorder->chan = chan;
935 event_recorder->priv->id = chan->priv->free_event_id++;
936 event_recorder->priv->parent.instrumentation = itype;
937 INIT_LIST_HEAD(&event_recorder->priv->parent.filter_bytecode_runtime_head);
938 INIT_LIST_HEAD(&event_recorder->priv->parent.enablers_ref_head);
939
940 switch (itype) {
941 case LTTNG_KERNEL_ABI_TRACEPOINT:
942 /* Event will be enabled by enabler sync. */
943 event_recorder->parent.enabled = 0;
944 event_recorder->priv->parent.registered = 0;
945 event_recorder->priv->parent.desc = lttng_event_desc_get(event_name);
946 if (!event_recorder->priv->parent.desc) {
947 ret = -ENOENT;
948 goto register_error;
949 }
950 /* Populate lttng_event structure before event registration. */
951 smp_wmb();
952 break;
953
954 case LTTNG_KERNEL_ABI_KPROBE:
955 /*
956 * Needs to be explicitly enabled after creation, since
957 * we may want to apply filters.
958 */
959 event_recorder->parent.enabled = 0;
960 event_recorder->priv->parent.registered = 1;
961 /*
962 * Populate lttng_event structure before event
963 * registration.
964 */
965 smp_wmb();
966 ret = lttng_kprobes_register_event(event_name,
967 event_param->u.kprobe.symbol_name,
968 event_param->u.kprobe.offset,
969 event_param->u.kprobe.addr,
970 event_recorder);
971 if (ret) {
972 ret = -EINVAL;
973 goto register_error;
974 }
975 ret = try_module_get(event_recorder->priv->parent.desc->owner);
976 WARN_ON_ONCE(!ret);
977 break;
978
979 case LTTNG_KERNEL_ABI_KRETPROBE:
980 {
981 struct lttng_kernel_event_recorder *event_recorder_return;
982 struct lttng_kernel_event_recorder_private *event_recorder_return_priv;
983
984 /* kretprobe defines 2 events */
985 /*
986 * Needs to be explicitly enabled after creation, since
987 * we may want to apply filters.
988 */
989 event_recorder->parent.enabled = 0;
990 event_recorder->priv->parent.registered = 1;
991
992 event_recorder_return = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
993 if (!event_recorder_return) {
994 ret = -ENOMEM;
995 goto register_error;
996 }
997 event_recorder_return_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
998 if (!event_recorder_return_priv) {
999 kmem_cache_free(event_recorder_cache, event_recorder_return);
1000 ret = -ENOMEM;
1001 goto register_error;
1002 }
1003 event_recorder_return_priv->pub = event_recorder_return;
1004 event_recorder_return_priv->parent.pub = &event_recorder_return->parent;
1005 event_recorder_return->priv = event_recorder_return_priv;
1006 event_recorder_return->parent.priv = &event_recorder_return_priv->parent;
1007 event_recorder_return->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
1008
1009 event_recorder_return->parent.run_filter = lttng_kernel_interpret_event_filter;
1010 event_recorder_return->chan = chan;
1011 event_recorder_return->priv->id = chan->priv->free_event_id++;
1012 event_recorder_return->priv->parent.instrumentation = itype;
1013 event_recorder_return->parent.enabled = 0;
1014 event_recorder_return->priv->parent.registered = 1;
1015 INIT_LIST_HEAD(&event_recorder_return->priv->parent.filter_bytecode_runtime_head);
1016 INIT_LIST_HEAD(&event_recorder_return->priv->parent.enablers_ref_head);
1017 /*
1018 * Populate lttng_event structure before kretprobe registration.
1019 */
1020 smp_wmb();
1021 ret = lttng_kretprobes_register(event_name,
1022 event_param->u.kretprobe.symbol_name,
1023 event_param->u.kretprobe.offset,
1024 event_param->u.kretprobe.addr,
1025 event_recorder, event_recorder_return);
1026 if (ret) {
1027 kmem_cache_free(event_recorder_private_cache, event_recorder_return_priv);
1028 kmem_cache_free(event_recorder_cache, event_recorder_return);
1029 ret = -EINVAL;
1030 goto register_error;
1031 }
1032 /* Take 2 refs on the module: one per event. */
1033 ret = try_module_get(event_recorder->priv->parent.desc->owner);
1034 WARN_ON_ONCE(!ret);
1035 ret = try_module_get(event_recorder_return->priv->parent.desc->owner);
1036 WARN_ON_ONCE(!ret);
1037 ret = _lttng_event_metadata_statedump(chan->parent.session, chan,
1038 event_recorder_return);
1039 WARN_ON_ONCE(ret > 0);
1040 if (ret) {
1041 kmem_cache_free(event_recorder_private_cache, event_recorder_return_priv);
1042 kmem_cache_free(event_recorder_cache, event_recorder_return);
1043 module_put(event_recorder_return->priv->parent.desc->owner);
1044 module_put(event_recorder->priv->parent.desc->owner);
1045 goto statedump_error;
1046 }
1047 list_add(&event_recorder_return->priv->node, &chan->parent.session->priv->events);
1048 break;
1049 }
1050
1051 case LTTNG_KERNEL_ABI_SYSCALL:
1052 /*
1053 * Needs to be explicitly enabled after creation, since
1054 * we may want to apply filters.
1055 */
1056 event_recorder->parent.enabled = 0;
1057 event_recorder->priv->parent.registered = 0;
1058 event_recorder->priv->parent.desc = event_desc;
1059 switch (event_param->u.syscall.entryexit) {
1060 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1061 ret = -EINVAL;
1062 goto register_error;
1063 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1064 event_recorder->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1065 break;
1066 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1067 event_recorder->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1068 break;
1069 }
1070 switch (event_param->u.syscall.abi) {
1071 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1072 ret = -EINVAL;
1073 goto register_error;
1074 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1075 event_recorder->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1076 break;
1077 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1078 event_recorder->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1079 break;
1080 }
1081 if (!event_recorder->priv->parent.desc) {
1082 ret = -EINVAL;
1083 goto register_error;
1084 }
1085 break;
1086
1087 case LTTNG_KERNEL_ABI_UPROBE:
1088 /*
1089 * Needs to be explicitly enabled after creation, since
1090 * we may want to apply filters.
1091 */
1092 event_recorder->parent.enabled = 0;
1093 event_recorder->priv->parent.registered = 1;
1094
1095 /*
1096 * Populate lttng_event structure before event
1097 * registration.
1098 */
1099 smp_wmb();
1100
1101 ret = lttng_uprobes_register_event(event_param->name,
1102 event_param->u.uprobe.fd,
1103 event_recorder);
1104 if (ret)
1105 goto register_error;
1106 ret = try_module_get(event_recorder->priv->parent.desc->owner);
1107 WARN_ON_ONCE(!ret);
1108 break;
1109
1110 case LTTNG_KERNEL_ABI_FUNCTION:
1111 lttng_fallthrough;
1112 case LTTNG_KERNEL_ABI_NOOP:
1113 lttng_fallthrough;
1114 default:
1115 WARN_ON_ONCE(1);
1116 ret = -EINVAL;
1117 goto register_error;
1118 }
1119 ret = _lttng_event_metadata_statedump(chan->parent.session, chan, event_recorder);
1120 WARN_ON_ONCE(ret > 0);
1121 if (ret) {
1122 goto statedump_error;
1123 }
1124 hlist_add_head(&event_recorder->priv->hlist, head);
1125 list_add(&event_recorder->priv->node, &chan->parent.session->priv->events);
1126 return event_recorder;
1127
1128statedump_error:
1129 /* If a statedump error occurs, events will not be readable. */
1130register_error:
1131 kmem_cache_free(event_recorder_private_cache, event_recorder_priv);
1132cache_private_error:
1133 kmem_cache_free(event_recorder_cache, event_recorder);
1134cache_error:
1135exist:
1136type_error:
1137full:
1138 return ERR_PTR(ret);
1139}
1140
1141struct lttng_kernel_event_notifier *_lttng_event_notifier_create(
1142 const struct lttng_kernel_event_desc *event_desc,
1143 uint64_t token, uint64_t error_counter_index,
1144 struct lttng_event_notifier_group *event_notifier_group,
1145 struct lttng_kernel_abi_event_notifier *event_notifier_param,
1146 enum lttng_kernel_abi_instrumentation itype)
1147{
1148 struct lttng_kernel_event_notifier *event_notifier;
1149 struct lttng_kernel_event_notifier_private *event_notifier_priv;
1150 struct lttng_counter *error_counter;
1151 const char *event_name;
1152 struct hlist_head *head;
1153 int ret;
1154
1155 switch (itype) {
1156 case LTTNG_KERNEL_ABI_TRACEPOINT:
1157 event_name = event_desc->event_name;
1158 break;
1159
1160 case LTTNG_KERNEL_ABI_KPROBE:
1161 lttng_fallthrough;
1162 case LTTNG_KERNEL_ABI_UPROBE:
1163 lttng_fallthrough;
1164 case LTTNG_KERNEL_ABI_SYSCALL:
1165 event_name = event_notifier_param->event.name;
1166 break;
1167
1168 case LTTNG_KERNEL_ABI_KRETPROBE:
1169 lttng_fallthrough;
1170 case LTTNG_KERNEL_ABI_FUNCTION:
1171 lttng_fallthrough;
1172 case LTTNG_KERNEL_ABI_NOOP:
1173 lttng_fallthrough;
1174 default:
1175 WARN_ON_ONCE(1);
1176 ret = -EINVAL;
1177 goto type_error;
1178 }
1179
1180 head = utils_borrow_hash_table_bucket(event_notifier_group->event_notifiers_ht.table,
1181 LTTNG_EVENT_NOTIFIER_HT_SIZE, event_name);
1182 lttng_hlist_for_each_entry(event_notifier_priv, head, hlist) {
1183 WARN_ON_ONCE(!event_notifier_priv->parent.desc);
1184 if (!strncmp(event_notifier_priv->parent.desc->event_name, event_name,
1185 LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
1186 && event_notifier_group == event_notifier_priv->group
1187 && token == event_notifier_priv->parent.user_token) {
1188 ret = -EEXIST;
1189 goto exist;
1190 }
1191 }
1192
1193 event_notifier = kmem_cache_zalloc(event_notifier_cache, GFP_KERNEL);
1194 if (!event_notifier) {
1195 ret = -ENOMEM;
1196 goto cache_error;
1197 }
1198 event_notifier_priv = kmem_cache_zalloc(event_notifier_private_cache, GFP_KERNEL);
1199 if (!event_notifier_priv) {
1200 ret = -ENOMEM;
1201 goto cache_private_error;
1202 }
1203 event_notifier_priv->pub = event_notifier;
1204 event_notifier_priv->parent.pub = &event_notifier->parent;
1205 event_notifier->priv = event_notifier_priv;
1206 event_notifier->parent.priv = &event_notifier_priv->parent;
1207 event_notifier->parent.type = LTTNG_KERNEL_EVENT_TYPE_NOTIFIER;
1208
1209 event_notifier->priv->group = event_notifier_group;
1210 event_notifier->priv->parent.user_token = token;
1211 event_notifier->priv->error_counter_index = error_counter_index;
1212 event_notifier->priv->num_captures = 0;
1213 event_notifier->priv->parent.instrumentation = itype;
1214 event_notifier->notification_send = lttng_event_notifier_notification_send;
1215 INIT_LIST_HEAD(&event_notifier->priv->parent.filter_bytecode_runtime_head);
1216 INIT_LIST_HEAD(&event_notifier->priv->parent.enablers_ref_head);
1217 INIT_LIST_HEAD(&event_notifier->priv->capture_bytecode_runtime_head);
1218 event_notifier->parent.run_filter = lttng_kernel_interpret_event_filter;
1219
1220 switch (itype) {
1221 case LTTNG_KERNEL_ABI_TRACEPOINT:
1222 /* Event will be enabled by enabler sync. */
1223 event_notifier->parent.enabled = 0;
1224 event_notifier->priv->parent.registered = 0;
1225 event_notifier->priv->parent.desc = lttng_event_desc_get(event_name);
1226 if (!event_notifier->priv->parent.desc) {
1227 ret = -ENOENT;
1228 goto register_error;
1229 }
1230 /* Populate lttng_event_notifier structure before event registration. */
1231 smp_wmb();
1232 break;
1233
1234 case LTTNG_KERNEL_ABI_KPROBE:
1235 /*
1236 * Needs to be explicitly enabled after creation, since
1237 * we may want to apply filters.
1238 */
1239 event_notifier->parent.enabled = 0;
1240 event_notifier->priv->parent.registered = 1;
1241 /*
1242 * Populate lttng_event_notifier structure before event
1243 * registration.
1244 */
1245 smp_wmb();
1246 ret = lttng_kprobes_register_event_notifier(
1247 event_notifier_param->event.u.kprobe.symbol_name,
1248 event_notifier_param->event.u.kprobe.offset,
1249 event_notifier_param->event.u.kprobe.addr,
1250 event_notifier);
1251 if (ret) {
1252 ret = -EINVAL;
1253 goto register_error;
1254 }
1255 ret = try_module_get(event_notifier->priv->parent.desc->owner);
1256 WARN_ON_ONCE(!ret);
1257 break;
1258
1259 case LTTNG_KERNEL_ABI_SYSCALL:
1260 /*
1261 * Needs to be explicitly enabled after creation, since
1262 * we may want to apply filters.
1263 */
1264 event_notifier->parent.enabled = 0;
1265 event_notifier->priv->parent.registered = 0;
1266 event_notifier->priv->parent.desc = event_desc;
1267 switch (event_notifier_param->event.u.syscall.entryexit) {
1268 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1269 ret = -EINVAL;
1270 goto register_error;
1271 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1272 event_notifier->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1273 break;
1274 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1275 event_notifier->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1276 break;
1277 }
1278 switch (event_notifier_param->event.u.syscall.abi) {
1279 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1280 ret = -EINVAL;
1281 goto register_error;
1282 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1283 event_notifier->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1284 break;
1285 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1286 event_notifier->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1287 break;
1288 }
1289
1290 if (!event_notifier->priv->parent.desc) {
1291 ret = -EINVAL;
1292 goto register_error;
1293 }
1294 break;
1295
1296 case LTTNG_KERNEL_ABI_UPROBE:
1297 /*
1298 * Needs to be explicitly enabled after creation, since
1299 * we may want to apply filters.
1300 */
1301 event_notifier->parent.enabled = 0;
1302 event_notifier->priv->parent.registered = 1;
1303
1304 /*
1305 * Populate lttng_event_notifier structure before
1306 * event_notifier registration.
1307 */
1308 smp_wmb();
1309
1310 ret = lttng_uprobes_register_event_notifier(
1311 event_notifier_param->event.name,
1312 event_notifier_param->event.u.uprobe.fd,
1313 event_notifier);
1314 if (ret)
1315 goto register_error;
1316 ret = try_module_get(event_notifier->priv->parent.desc->owner);
1317 WARN_ON_ONCE(!ret);
1318 break;
1319
1320 case LTTNG_KERNEL_ABI_KRETPROBE:
1321 lttng_fallthrough;
1322 case LTTNG_KERNEL_ABI_FUNCTION:
1323 lttng_fallthrough;
1324 case LTTNG_KERNEL_ABI_NOOP:
1325 lttng_fallthrough;
1326 default:
1327 WARN_ON_ONCE(1);
1328 ret = -EINVAL;
1329 goto register_error;
1330 }
1331
1332 list_add(&event_notifier->priv->node, &event_notifier_group->event_notifiers_head);
1333 hlist_add_head(&event_notifier->priv->hlist, head);
1334
1335 /*
1336 * Clear the error counter bucket. The sessiond keeps track of which
1337 * bucket is currently in use. We trust it. The session lock
1338 * synchronizes against concurrent creation of the error
1339 * counter.
1340 */
1341 error_counter = event_notifier_group->error_counter;
1342 if (error_counter) {
1343 size_t dimension_index[1];
1344
1345 /*
1346 * Check that the index is within the boundary of the counter.
1347 */
1348 if (event_notifier->priv->error_counter_index >= event_notifier_group->error_counter_len) {
1349 printk(KERN_INFO "LTTng: event_notifier: Error counter index out-of-bound: counter-len=%zu, index=%llu\n",
1350 event_notifier_group->error_counter_len, event_notifier->priv->error_counter_index);
1351 ret = -EINVAL;
1352 goto register_error;
1353 }
1354
1355 dimension_index[0] = event_notifier->priv->error_counter_index;
1356 ret = error_counter->ops->counter_clear(error_counter->counter, dimension_index);
1357 if (ret) {
1358 printk(KERN_INFO "LTTng: event_notifier: Unable to clear error counter bucket %llu\n",
1359 event_notifier->priv->error_counter_index);
1360 goto register_error;
1361 }
1362 }
1363
1364 return event_notifier;
1365
1366register_error:
1367 kmem_cache_free(event_notifier_private_cache, event_notifier_priv);
1368cache_private_error:
1369 kmem_cache_free(event_notifier_cache, event_notifier);
1370cache_error:
1371exist:
1372type_error:
1373 return ERR_PTR(ret);
1374}
1375
1376int lttng_kernel_counter_read(struct lttng_counter *counter,
1377 const size_t *dim_indexes, int32_t cpu,
1378 int64_t *val, bool *overflow, bool *underflow)
1379{
1380 return counter->ops->counter_read(counter->counter, dim_indexes,
1381 cpu, val, overflow, underflow);
1382}
1383
1384int lttng_kernel_counter_aggregate(struct lttng_counter *counter,
1385 const size_t *dim_indexes, int64_t *val,
1386 bool *overflow, bool *underflow)
1387{
1388 return counter->ops->counter_aggregate(counter->counter, dim_indexes,
1389 val, overflow, underflow);
1390}
1391
1392int lttng_kernel_counter_clear(struct lttng_counter *counter,
1393 const size_t *dim_indexes)
1394{
1395 return counter->ops->counter_clear(counter->counter, dim_indexes);
1396}
1397
1398struct lttng_kernel_event_recorder *lttng_kernel_event_recorder_create(struct lttng_event_recorder_enabler *event_enabler,
1399 const struct lttng_kernel_event_desc *event_desc)
1400{
1401 struct lttng_kernel_event_recorder *event;
1402
1403 mutex_lock(&sessions_mutex);
1404 event = _lttng_kernel_event_recorder_create(event_enabler, event_desc);
1405 mutex_unlock(&sessions_mutex);
1406 return event;
1407}
1408
1409struct lttng_kernel_event_notifier *lttng_event_notifier_create(
1410 const struct lttng_kernel_event_desc *event_desc,
1411 uint64_t id, uint64_t error_counter_index,
1412 struct lttng_event_notifier_group *event_notifier_group,
1413 struct lttng_kernel_abi_event_notifier *event_notifier_param,
1414 enum lttng_kernel_abi_instrumentation itype)
1415{
1416 struct lttng_kernel_event_notifier *event_notifier;
1417
1418 mutex_lock(&sessions_mutex);
1419 event_notifier = _lttng_event_notifier_create(event_desc, id,
1420 error_counter_index, event_notifier_group,
1421 event_notifier_param, itype);
1422 mutex_unlock(&sessions_mutex);
1423 return event_notifier;
1424}
1425
1426/* Only used for tracepoints for now. */
1427static
1428void register_event(struct lttng_kernel_event_recorder *event_recorder)
1429{
1430 const struct lttng_kernel_event_desc *desc;
1431 int ret = -EINVAL;
1432
1433 if (event_recorder->priv->parent.registered)
1434 return;
1435
1436 desc = event_recorder->priv->parent.desc;
1437 switch (event_recorder->priv->parent.instrumentation) {
1438 case LTTNG_KERNEL_ABI_TRACEPOINT:
1439 ret = lttng_wrapper_tracepoint_probe_register(desc->event_kname,
1440 desc->tp_class->probe_callback,
1441 event_recorder);
1442 break;
1443
1444 case LTTNG_KERNEL_ABI_SYSCALL:
1445 ret = lttng_syscall_filter_enable_event(event_recorder->chan, event_recorder);
1446 break;
1447
1448 case LTTNG_KERNEL_ABI_KPROBE:
1449 lttng_fallthrough;
1450 case LTTNG_KERNEL_ABI_UPROBE:
1451 lttng_fallthrough;
1452 case LTTNG_KERNEL_ABI_KRETPROBE:
1453 ret = 0;
1454 break;
1455
1456 case LTTNG_KERNEL_ABI_FUNCTION:
1457 lttng_fallthrough;
1458 case LTTNG_KERNEL_ABI_NOOP:
1459 lttng_fallthrough;
1460 default:
1461 WARN_ON_ONCE(1);
1462 }
1463 if (!ret)
1464 event_recorder->priv->parent.registered = 1;
1465}
1466
1467/*
1468 * Only used internally at session destruction.
1469 */
1470int _lttng_event_unregister(struct lttng_kernel_event_recorder *event_recorder)
1471{
1472 struct lttng_kernel_event_common_private *event_priv = &event_recorder->priv->parent;
1473 const struct lttng_kernel_event_desc *desc;
1474 int ret = -EINVAL;
1475
1476 if (!event_priv->registered)
1477 return 0;
1478
1479 desc = event_priv->desc;
1480 switch (event_priv->instrumentation) {
1481 case LTTNG_KERNEL_ABI_TRACEPOINT:
1482 ret = lttng_wrapper_tracepoint_probe_unregister(event_priv->desc->event_kname,
1483 event_priv->desc->tp_class->probe_callback,
1484 event_recorder);
1485 break;
1486
1487 case LTTNG_KERNEL_ABI_KPROBE:
1488 lttng_kprobes_unregister_event(event_recorder);
1489 ret = 0;
1490 break;
1491
1492 case LTTNG_KERNEL_ABI_KRETPROBE:
1493 lttng_kretprobes_unregister(event_recorder);
1494 ret = 0;
1495 break;
1496
1497 case LTTNG_KERNEL_ABI_SYSCALL:
1498 ret = lttng_syscall_filter_disable_event(event_recorder->chan, event_recorder);
1499 break;
1500
1501 case LTTNG_KERNEL_ABI_NOOP:
1502 ret = 0;
1503 break;
1504
1505 case LTTNG_KERNEL_ABI_UPROBE:
1506 lttng_uprobes_unregister_event(event_recorder);
1507 ret = 0;
1508 break;
1509
1510 case LTTNG_KERNEL_ABI_FUNCTION:
1511 lttng_fallthrough;
1512 default:
1513 WARN_ON_ONCE(1);
1514 }
1515 if (!ret)
1516 event_priv->registered = 0;
1517 return ret;
1518}
1519
1520/* Only used for tracepoints for now. */
1521static
1522void register_event_notifier(struct lttng_kernel_event_notifier *event_notifier)
1523{
1524 const struct lttng_kernel_event_desc *desc;
1525 int ret = -EINVAL;
1526
1527 if (event_notifier->priv->parent.registered)
1528 return;
1529
1530 desc = event_notifier->priv->parent.desc;
1531 switch (event_notifier->priv->parent.instrumentation) {
1532 case LTTNG_KERNEL_ABI_TRACEPOINT:
1533 ret = lttng_wrapper_tracepoint_probe_register(desc->event_kname,
1534 desc->tp_class->probe_callback,
1535 event_notifier);
1536 break;
1537
1538 case LTTNG_KERNEL_ABI_SYSCALL:
1539 ret = lttng_syscall_filter_enable_event_notifier(event_notifier);
1540 break;
1541
1542 case LTTNG_KERNEL_ABI_KPROBE:
1543 lttng_fallthrough;
1544 case LTTNG_KERNEL_ABI_UPROBE:
1545 ret = 0;
1546 break;
1547
1548 case LTTNG_KERNEL_ABI_KRETPROBE:
1549 lttng_fallthrough;
1550 case LTTNG_KERNEL_ABI_FUNCTION:
1551 lttng_fallthrough;
1552 case LTTNG_KERNEL_ABI_NOOP:
1553 lttng_fallthrough;
1554 default:
1555 WARN_ON_ONCE(1);
1556 }
1557 if (!ret)
1558 event_notifier->priv->parent.registered = 1;
1559}
1560
1561static
1562int _lttng_event_notifier_unregister(
1563 struct lttng_kernel_event_notifier *event_notifier)
1564{
1565 const struct lttng_kernel_event_desc *desc;
1566 int ret = -EINVAL;
1567
1568 if (!event_notifier->priv->parent.registered)
1569 return 0;
1570
1571 desc = event_notifier->priv->parent.desc;
1572 switch (event_notifier->priv->parent.instrumentation) {
1573 case LTTNG_KERNEL_ABI_TRACEPOINT:
1574 ret = lttng_wrapper_tracepoint_probe_unregister(event_notifier->priv->parent.desc->event_kname,
1575 event_notifier->priv->parent.desc->tp_class->probe_callback,
1576 event_notifier);
1577 break;
1578
1579 case LTTNG_KERNEL_ABI_KPROBE:
1580 lttng_kprobes_unregister_event_notifier(event_notifier);
1581 ret = 0;
1582 break;
1583
1584 case LTTNG_KERNEL_ABI_UPROBE:
1585 lttng_uprobes_unregister_event_notifier(event_notifier);
1586 ret = 0;
1587 break;
1588
1589 case LTTNG_KERNEL_ABI_SYSCALL:
1590 ret = lttng_syscall_filter_disable_event_notifier(event_notifier);
1591 break;
1592
1593 case LTTNG_KERNEL_ABI_KRETPROBE:
1594 lttng_fallthrough;
1595 case LTTNG_KERNEL_ABI_FUNCTION:
1596 lttng_fallthrough;
1597 case LTTNG_KERNEL_ABI_NOOP:
1598 lttng_fallthrough;
1599 default:
1600 WARN_ON_ONCE(1);
1601 }
1602 if (!ret)
1603 event_notifier->priv->parent.registered = 0;
1604 return ret;
1605}
1606
1607/*
1608 * Only used internally at session destruction.
1609 */
1610static
1611void _lttng_event_destroy(struct lttng_kernel_event_common *event)
1612{
1613 struct lttng_kernel_event_common_private *event_priv = event->priv;
1614 struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref;
1615
1616 lttng_free_event_filter_runtime(event);
1617 /* Free event enabler refs */
1618 list_for_each_entry_safe(enabler_ref, tmp_enabler_ref,
1619 &event_priv->enablers_ref_head, node)
1620 kfree(enabler_ref);
1621
1622 switch (event->type) {
1623 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1624 {
1625 struct lttng_kernel_event_recorder *event_recorder =
1626 container_of(event, struct lttng_kernel_event_recorder, parent);
1627
1628 switch (event_priv->instrumentation) {
1629 case LTTNG_KERNEL_ABI_TRACEPOINT:
1630 lttng_event_desc_put(event_priv->desc);
1631 break;
1632
1633 case LTTNG_KERNEL_ABI_KPROBE:
1634 module_put(event_priv->desc->owner);
1635 lttng_kprobes_destroy_event_private(event_recorder);
1636 break;
1637
1638 case LTTNG_KERNEL_ABI_KRETPROBE:
1639 module_put(event_priv->desc->owner);
1640 lttng_kretprobes_destroy_private(event_recorder);
1641 break;
1642
1643 case LTTNG_KERNEL_ABI_SYSCALL:
1644 break;
1645
1646 case LTTNG_KERNEL_ABI_UPROBE:
1647 module_put(event_priv->desc->owner);
1648 lttng_uprobes_destroy_event_private(event_recorder);
1649 break;
1650
1651 case LTTNG_KERNEL_ABI_FUNCTION:
1652 lttng_fallthrough;
1653 case LTTNG_KERNEL_ABI_NOOP:
1654 lttng_fallthrough;
1655 default:
1656 WARN_ON_ONCE(1);
1657 }
1658 list_del(&event_recorder->priv->node);
1659 kmem_cache_free(event_recorder_private_cache, event_recorder->priv);
1660 kmem_cache_free(event_recorder_cache, event_recorder);
1661 break;
1662 }
1663 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1664 {
1665 struct lttng_kernel_event_notifier *event_notifier =
1666 container_of(event, struct lttng_kernel_event_notifier, parent);
1667
1668 switch (event_notifier->priv->parent.instrumentation) {
1669 case LTTNG_KERNEL_ABI_TRACEPOINT:
1670 lttng_event_desc_put(event_notifier->priv->parent.desc);
1671 break;
1672
1673 case LTTNG_KERNEL_ABI_KPROBE:
1674 module_put(event_notifier->priv->parent.desc->owner);
1675 lttng_kprobes_destroy_event_notifier_private(event_notifier);
1676 break;
1677
1678 case LTTNG_KERNEL_ABI_SYSCALL:
1679 break;
1680
1681 case LTTNG_KERNEL_ABI_UPROBE:
1682 module_put(event_notifier->priv->parent.desc->owner);
1683 lttng_uprobes_destroy_event_notifier_private(event_notifier);
1684 break;
1685
1686 case LTTNG_KERNEL_ABI_KRETPROBE:
1687 lttng_fallthrough;
1688 case LTTNG_KERNEL_ABI_FUNCTION:
1689 lttng_fallthrough;
1690 case LTTNG_KERNEL_ABI_NOOP:
1691 lttng_fallthrough;
1692 default:
1693 WARN_ON_ONCE(1);
1694 }
1695 list_del(&event_notifier->priv->node);
1696 kmem_cache_free(event_notifier_private_cache, event_notifier->priv);
1697 kmem_cache_free(event_notifier_cache, event_notifier);
1698 break;
1699 }
1700 default:
1701 WARN_ON_ONCE(1);
1702 }
1703}
1704
1705struct lttng_kernel_id_tracker *get_tracker(struct lttng_kernel_session *session,
1706 enum tracker_type tracker_type)
1707{
1708 switch (tracker_type) {
1709 case TRACKER_PID:
1710 return &session->pid_tracker;
1711 case TRACKER_VPID:
1712 return &session->vpid_tracker;
1713 case TRACKER_UID:
1714 return &session->uid_tracker;
1715 case TRACKER_VUID:
1716 return &session->vuid_tracker;
1717 case TRACKER_GID:
1718 return &session->gid_tracker;
1719 case TRACKER_VGID:
1720 return &session->vgid_tracker;
1721 default:
1722 WARN_ON_ONCE(1);
1723 return NULL;
1724 }
1725}
1726
1727int lttng_session_track_id(struct lttng_kernel_session *session,
1728 enum tracker_type tracker_type, int id)
1729{
1730 struct lttng_kernel_id_tracker *tracker;
1731 int ret;
1732
1733 tracker = get_tracker(session, tracker_type);
1734 if (!tracker)
1735 return -EINVAL;
1736 if (id < -1)
1737 return -EINVAL;
1738 mutex_lock(&sessions_mutex);
1739 if (id == -1) {
1740 /* track all ids: destroy tracker. */
1741 lttng_id_tracker_destroy(tracker, true);
1742 ret = 0;
1743 } else {
1744 ret = lttng_id_tracker_add(tracker, id);
1745 }
1746 mutex_unlock(&sessions_mutex);
1747 return ret;
1748}
1749
1750int lttng_session_untrack_id(struct lttng_kernel_session *session,
1751 enum tracker_type tracker_type, int id)
1752{
1753 struct lttng_kernel_id_tracker *tracker;
1754 int ret;
1755
1756 tracker = get_tracker(session, tracker_type);
1757 if (!tracker)
1758 return -EINVAL;
1759 if (id < -1)
1760 return -EINVAL;
1761 mutex_lock(&sessions_mutex);
1762 if (id == -1) {
1763 /* untrack all ids: replace by empty tracker. */
1764 ret = lttng_id_tracker_empty_set(tracker);
1765 } else {
1766 ret = lttng_id_tracker_del(tracker, id);
1767 }
1768 mutex_unlock(&sessions_mutex);
1769 return ret;
1770}
1771
1772static
1773void *id_list_start(struct seq_file *m, loff_t *pos)
1774{
1775 struct lttng_kernel_id_tracker *id_tracker = m->private;
1776 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1777 struct lttng_id_hash_node *e;
1778 int iter = 0, i;
1779
1780 mutex_lock(&sessions_mutex);
1781 if (id_tracker_p) {
1782 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1783 struct hlist_head *head = &id_tracker_p->id_hash[i];
1784
1785 lttng_hlist_for_each_entry(e, head, hlist) {
1786 if (iter++ >= *pos)
1787 return e;
1788 }
1789 }
1790 } else {
1791 /* ID tracker disabled. */
1792 if (iter >= *pos && iter == 0) {
1793 return id_tracker_p; /* empty tracker */
1794 }
1795 iter++;
1796 }
1797 /* End of list */
1798 return NULL;
1799}
1800
1801/* Called with sessions_mutex held. */
1802static
1803void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
1804{
1805 struct lttng_kernel_id_tracker *id_tracker = m->private;
1806 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1807 struct lttng_id_hash_node *e;
1808 int iter = 0, i;
1809
1810 (*ppos)++;
1811 if (id_tracker_p) {
1812 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1813 struct hlist_head *head = &id_tracker_p->id_hash[i];
1814
1815 lttng_hlist_for_each_entry(e, head, hlist) {
1816 if (iter++ >= *ppos)
1817 return e;
1818 }
1819 }
1820 } else {
1821 /* ID tracker disabled. */
1822 if (iter >= *ppos && iter == 0)
1823 return p; /* empty tracker */
1824 iter++;
1825 }
1826
1827 /* End of list */
1828 return NULL;
1829}
1830
1831static
1832void id_list_stop(struct seq_file *m, void *p)
1833{
1834 mutex_unlock(&sessions_mutex);
1835}
1836
1837static
1838int id_list_show(struct seq_file *m, void *p)
1839{
1840 struct lttng_kernel_id_tracker *id_tracker = m->private;
1841 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1842 int id;
1843
1844 if (p == id_tracker_p) {
1845 /* Tracker disabled. */
1846 id = -1;
1847 } else {
1848 const struct lttng_id_hash_node *e = p;
1849
1850 id = lttng_id_tracker_get_node_id(e);
1851 }
1852 switch (id_tracker->priv->tracker_type) {
1853 case TRACKER_PID:
1854 seq_printf(m, "process { pid = %d; };\n", id);
1855 break;
1856 case TRACKER_VPID:
1857 seq_printf(m, "process { vpid = %d; };\n", id);
1858 break;
1859 case TRACKER_UID:
1860 seq_printf(m, "user { uid = %d; };\n", id);
1861 break;
1862 case TRACKER_VUID:
1863 seq_printf(m, "user { vuid = %d; };\n", id);
1864 break;
1865 case TRACKER_GID:
1866 seq_printf(m, "group { gid = %d; };\n", id);
1867 break;
1868 case TRACKER_VGID:
1869 seq_printf(m, "group { vgid = %d; };\n", id);
1870 break;
1871 default:
1872 seq_printf(m, "UNKNOWN { field = %d };\n", id);
1873 }
1874 return 0;
1875}
1876
1877static
1878const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1879 .start = id_list_start,
1880 .next = id_list_next,
1881 .stop = id_list_stop,
1882 .show = id_list_show,
1883};
1884
1885static
1886int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
1887{
1888 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
1889}
1890
1891static
1892int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
1893{
1894 struct seq_file *m = file->private_data;
1895 struct lttng_kernel_id_tracker *id_tracker = m->private;
1896 int ret;
1897
1898 WARN_ON_ONCE(!id_tracker);
1899 ret = seq_release(inode, file);
1900 if (!ret)
1901 fput(id_tracker->priv->session->priv->file);
1902 return ret;
1903}
1904
1905const struct file_operations lttng_tracker_ids_list_fops = {
1906 .owner = THIS_MODULE,
1907 .open = lttng_tracker_ids_list_open,
1908 .read = seq_read,
1909 .llseek = seq_lseek,
1910 .release = lttng_tracker_ids_list_release,
1911};
1912
1913int lttng_session_list_tracker_ids(struct lttng_kernel_session *session,
1914 enum tracker_type tracker_type)
1915{
1916 struct file *tracker_ids_list_file;
1917 struct seq_file *m;
1918 int file_fd, ret;
1919
1920 file_fd = lttng_get_unused_fd();
1921 if (file_fd < 0) {
1922 ret = file_fd;
1923 goto fd_error;
1924 }
1925
1926 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1927 &lttng_tracker_ids_list_fops,
1928 NULL, O_RDWR);
1929 if (IS_ERR(tracker_ids_list_file)) {
1930 ret = PTR_ERR(tracker_ids_list_file);
1931 goto file_error;
1932 }
1933 if (!atomic_long_add_unless(&session->priv->file->f_count, 1, LONG_MAX)) {
1934 ret = -EOVERFLOW;
1935 goto refcount_error;
1936 }
1937 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
1938 if (ret < 0)
1939 goto open_error;
1940 m = tracker_ids_list_file->private_data;
1941
1942 m->private = get_tracker(session, tracker_type);
1943 BUG_ON(!m->private);
1944 fd_install(file_fd, tracker_ids_list_file);
1945
1946 return file_fd;
1947
1948open_error:
1949 atomic_long_dec(&session->priv->file->f_count);
1950refcount_error:
1951 fput(tracker_ids_list_file);
1952file_error:
1953 put_unused_fd(file_fd);
1954fd_error:
1955 return ret;
1956}
1957
1958/*
1959 * Enabler management.
1960 */
1961static
1962int lttng_match_enabler_star_glob(const char *desc_name,
1963 const char *pattern)
1964{
1965 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1966 desc_name, LTTNG_SIZE_MAX))
1967 return 0;
1968 return 1;
1969}
1970
1971static
1972int lttng_match_enabler_name(const char *desc_name,
1973 const char *name)
1974{
1975 if (strcmp(desc_name, name))
1976 return 0;
1977 return 1;
1978}
1979
1980int lttng_desc_match_enabler(const struct lttng_kernel_event_desc *desc,
1981 struct lttng_event_enabler_common *enabler)
1982{
1983 const char *desc_name, *enabler_name;
1984 bool compat = false, entry = false;
1985
1986 enabler_name = enabler->event_param.name;
1987 switch (enabler->event_param.instrumentation) {
1988 case LTTNG_KERNEL_ABI_TRACEPOINT:
1989 desc_name = desc->event_name;
1990 switch (enabler->format_type) {
1991 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
1992 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1993 case LTTNG_ENABLER_FORMAT_NAME:
1994 return lttng_match_enabler_name(desc_name, enabler_name);
1995 default:
1996 return -EINVAL;
1997 }
1998 break;
1999
2000 case LTTNG_KERNEL_ABI_SYSCALL:
2001 desc_name = desc->event_name;
2002 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
2003 desc_name += strlen("compat_");
2004 compat = true;
2005 }
2006 if (!strncmp(desc_name, "syscall_exit_",
2007 strlen("syscall_exit_"))) {
2008 desc_name += strlen("syscall_exit_");
2009 } else if (!strncmp(desc_name, "syscall_entry_",
2010 strlen("syscall_entry_"))) {
2011 desc_name += strlen("syscall_entry_");
2012 entry = true;
2013 } else {
2014 WARN_ON_ONCE(1);
2015 return -EINVAL;
2016 }
2017 switch (enabler->event_param.u.syscall.entryexit) {
2018 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
2019 break;
2020 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
2021 if (!entry)
2022 return 0;
2023 break;
2024 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
2025 if (entry)
2026 return 0;
2027 break;
2028 default:
2029 return -EINVAL;
2030 }
2031 switch (enabler->event_param.u.syscall.abi) {
2032 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
2033 break;
2034 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
2035 if (compat)
2036 return 0;
2037 break;
2038 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
2039 if (!compat)
2040 return 0;
2041 break;
2042 default:
2043 return -EINVAL;
2044 }
2045 switch (enabler->event_param.u.syscall.match) {
2046 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME:
2047 switch (enabler->format_type) {
2048 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
2049 return lttng_match_enabler_star_glob(desc_name, enabler_name);
2050 case LTTNG_ENABLER_FORMAT_NAME:
2051 return lttng_match_enabler_name(desc_name, enabler_name);
2052 default:
2053 return -EINVAL;
2054 }
2055 break;
2056 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NR:
2057 return -EINVAL; /* Not implemented. */
2058 default:
2059 return -EINVAL;
2060 }
2061 break;
2062
2063 default:
2064 WARN_ON_ONCE(1);
2065 return -EINVAL;
2066 }
2067}
2068
2069static
2070int lttng_event_enabler_match_event(struct lttng_event_recorder_enabler *event_enabler,
2071 struct lttng_kernel_event_recorder *event_recorder)
2072{
2073 struct lttng_event_enabler_common *base_enabler = lttng_event_recorder_enabler_as_enabler(
2074 event_enabler);
2075
2076 if (base_enabler->event_param.instrumentation != event_recorder->priv->parent.instrumentation)
2077 return 0;
2078 if (lttng_desc_match_enabler(event_recorder->priv->parent.desc, base_enabler)
2079 && event_recorder->chan == event_enabler->chan)
2080 return 1;
2081 else
2082 return 0;
2083}
2084
2085static
2086int lttng_event_notifier_enabler_match_event_notifier(struct lttng_event_notifier_enabler *event_notifier_enabler,
2087 struct lttng_kernel_event_notifier *event_notifier)
2088{
2089 struct lttng_event_enabler_common *base_enabler = lttng_event_notifier_enabler_as_enabler(
2090 event_notifier_enabler);
2091
2092 if (base_enabler->event_param.instrumentation != event_notifier->priv->parent.instrumentation)
2093 return 0;
2094 if (lttng_desc_match_enabler(event_notifier->priv->parent.desc, base_enabler)
2095 && event_notifier->priv->group == event_notifier_enabler->group
2096 && event_notifier->priv->parent.user_token == event_notifier_enabler->parent.user_token)
2097 return 1;
2098 else
2099 return 0;
2100}
2101
2102static
2103struct lttng_enabler_ref *lttng_enabler_ref(
2104 struct list_head *enablers_ref_list,
2105 struct lttng_event_enabler_common *enabler)
2106{
2107 struct lttng_enabler_ref *enabler_ref;
2108
2109 list_for_each_entry(enabler_ref, enablers_ref_list, node) {
2110 if (enabler_ref->ref == enabler)
2111 return enabler_ref;
2112 }
2113 return NULL;
2114}
2115
2116static
2117void lttng_create_tracepoint_event_if_missing(struct lttng_event_recorder_enabler *event_enabler)
2118{
2119 struct lttng_kernel_session *session = event_enabler->chan->parent.session;
2120 struct lttng_kernel_probe_desc *probe_desc;
2121 const struct lttng_kernel_event_desc *desc;
2122 int i;
2123 struct list_head *probe_list;
2124
2125 probe_list = lttng_get_probe_list_head();
2126 /*
2127 * For each probe event, if we find that a probe event matches
2128 * our enabler, create an associated lttng_event if not
2129 * already present.
2130 */
2131 list_for_each_entry(probe_desc, probe_list, head) {
2132 for (i = 0; i < probe_desc->nr_events; i++) {
2133 int found = 0;
2134 struct hlist_head *head;
2135 struct lttng_kernel_event_recorder_private *event_recorder_private;
2136 struct lttng_kernel_event_recorder *event_recorder;
2137
2138 desc = probe_desc->event_desc[i];
2139 if (!lttng_desc_match_enabler(desc,
2140 lttng_event_recorder_enabler_as_enabler(event_enabler)))
2141 continue;
2142
2143 /*
2144 * Check if already created.
2145 */
2146 head = utils_borrow_hash_table_bucket(
2147 session->priv->events_ht.table, LTTNG_EVENT_HT_SIZE,
2148 desc->event_name);
2149 lttng_hlist_for_each_entry(event_recorder_private, head, hlist) {
2150 if (event_recorder_private->parent.desc == desc
2151 && event_recorder_private->pub->chan == event_enabler->chan)
2152 found = 1;
2153 }
2154 if (found)
2155 continue;
2156
2157 /*
2158 * We need to create an event for this
2159 * event probe.
2160 */
2161 event_recorder = _lttng_kernel_event_recorder_create(event_enabler, desc);
2162 if (!event_recorder) {
2163 printk(KERN_INFO "LTTng: Unable to create event %s\n",
2164 probe_desc->event_desc[i]->event_name);
2165 }
2166 }
2167 }
2168}
2169
2170static
2171void lttng_create_tracepoint_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2172{
2173 struct lttng_event_notifier_group *event_notifier_group = event_notifier_enabler->group;
2174 struct lttng_kernel_probe_desc *probe_desc;
2175 const struct lttng_kernel_event_desc *desc;
2176 int i;
2177 struct list_head *probe_list;
2178
2179 probe_list = lttng_get_probe_list_head();
2180 /*
2181 * For each probe event, if we find that a probe event matches
2182 * our enabler, create an associated lttng_event_notifier if not
2183 * already present.
2184 */
2185 list_for_each_entry(probe_desc, probe_list, head) {
2186 for (i = 0; i < probe_desc->nr_events; i++) {
2187 int found = 0;
2188 struct hlist_head *head;
2189 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2190 struct lttng_kernel_event_notifier *event_notifier;
2191
2192 desc = probe_desc->event_desc[i];
2193 if (!lttng_desc_match_enabler(desc,
2194 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)))
2195 continue;
2196
2197 /*
2198 * Check if already created.
2199 */
2200 head = utils_borrow_hash_table_bucket(
2201 event_notifier_group->event_notifiers_ht.table,
2202 LTTNG_EVENT_NOTIFIER_HT_SIZE, desc->event_name);
2203 lttng_hlist_for_each_entry(event_notifier_priv, head, hlist) {
2204 if (event_notifier_priv->parent.desc == desc
2205 && event_notifier_priv->parent.user_token == event_notifier_enabler->parent.user_token)
2206 found = 1;
2207 }
2208 if (found)
2209 continue;
2210
2211 /*
2212 * We need to create a event_notifier for this event probe.
2213 */
2214 event_notifier = _lttng_event_notifier_create(desc,
2215 event_notifier_enabler->parent.user_token,
2216 event_notifier_enabler->error_counter_index,
2217 event_notifier_group, NULL,
2218 LTTNG_KERNEL_ABI_TRACEPOINT);
2219 if (IS_ERR(event_notifier)) {
2220 printk(KERN_INFO "Unable to create event_notifier %s\n",
2221 probe_desc->event_desc[i]->event_name);
2222 }
2223 }
2224 }
2225}
2226
2227static
2228void lttng_create_syscall_event_if_missing(struct lttng_event_recorder_enabler *event_enabler)
2229{
2230 int ret;
2231
2232 ret = lttng_syscalls_register_event(event_enabler);
2233 WARN_ON_ONCE(ret);
2234}
2235
2236static
2237void lttng_create_syscall_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2238{
2239 int ret;
2240
2241 ret = lttng_syscalls_register_event_notifier(event_notifier_enabler);
2242 WARN_ON_ONCE(ret);
2243 ret = lttng_syscalls_create_matching_event_notifiers(event_notifier_enabler);
2244 WARN_ON_ONCE(ret);
2245}
2246
2247/*
2248 * Create struct lttng_kernel_event_recorder if it is missing and present in the list of
2249 * tracepoint probes.
2250 * Should be called with sessions mutex held.
2251 */
2252static
2253void lttng_create_event_if_missing(struct lttng_event_recorder_enabler *event_enabler)
2254{
2255 switch (event_enabler->parent.event_param.instrumentation) {
2256 case LTTNG_KERNEL_ABI_TRACEPOINT:
2257 lttng_create_tracepoint_event_if_missing(event_enabler);
2258 break;
2259
2260 case LTTNG_KERNEL_ABI_SYSCALL:
2261 lttng_create_syscall_event_if_missing(event_enabler);
2262 break;
2263
2264 default:
2265 WARN_ON_ONCE(1);
2266 break;
2267 }
2268}
2269
2270/*
2271 * Create events associated with an event_enabler (if not already present),
2272 * and add backward reference from the event to the enabler.
2273 * Should be called with sessions mutex held.
2274 */
2275static
2276int lttng_event_enabler_ref_events(struct lttng_event_recorder_enabler *event_enabler)
2277{
2278 struct lttng_kernel_channel_buffer *chan = event_enabler->chan;
2279 struct lttng_kernel_session *session = event_enabler->chan->parent.session;
2280 struct lttng_event_enabler_common *base_enabler = lttng_event_recorder_enabler_as_enabler(event_enabler);
2281 struct lttng_kernel_event_recorder_private *event_recorder_priv;
2282
2283 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_ABI_SYSCALL &&
2284 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL &&
2285 base_enabler->event_param.u.syscall.match == LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME &&
2286 !strcmp(base_enabler->event_param.name, "*")) {
2287 int enabled = base_enabler->enabled;
2288 enum lttng_kernel_abi_syscall_entryexit entryexit = base_enabler->event_param.u.syscall.entryexit;
2289
2290 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2291 WRITE_ONCE(chan->priv->parent.syscall_table.syscall_all_entry, enabled);
2292
2293 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2294 WRITE_ONCE(chan->priv->parent.syscall_table.syscall_all_exit, enabled);
2295 }
2296
2297 /* First ensure that probe events are created for this enabler. */
2298 lttng_create_event_if_missing(event_enabler);
2299
2300 /* For each event matching event_enabler in session event list. */
2301 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
2302 struct lttng_kernel_event_recorder *event_recorder = event_recorder_priv->pub;
2303 struct lttng_enabler_ref *enabler_ref;
2304
2305 if (!lttng_event_enabler_match_event(event_enabler, event_recorder))
2306 continue;
2307 enabler_ref = lttng_enabler_ref(&event_recorder_priv->parent.enablers_ref_head,
2308 lttng_event_recorder_enabler_as_enabler(event_enabler));
2309 if (!enabler_ref) {
2310 /*
2311 * If no backward ref, create it.
2312 * Add backward ref from event to event_enabler.
2313 */
2314 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2315 if (!enabler_ref)
2316 return -ENOMEM;
2317 enabler_ref->ref = lttng_event_recorder_enabler_as_enabler(event_enabler);
2318 list_add(&enabler_ref->node,
2319 &event_recorder_priv->parent.enablers_ref_head);
2320 }
2321
2322 /*
2323 * Link filter bytecodes if not linked yet.
2324 */
2325 lttng_enabler_link_bytecode(event_recorder_priv->parent.desc,
2326 lttng_static_ctx,
2327 &event_recorder_priv->parent.filter_bytecode_runtime_head,
2328 &lttng_event_recorder_enabler_as_enabler(event_enabler)->filter_bytecode_head);
2329 }
2330 return 0;
2331}
2332
2333/*
2334 * Create struct lttng_kernel_event_notifier if it is missing and present in the list of
2335 * tracepoint probes.
2336 * Should be called with sessions mutex held.
2337 */
2338static
2339void lttng_create_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2340{
2341 switch (event_notifier_enabler->parent.event_param.instrumentation) {
2342 case LTTNG_KERNEL_ABI_TRACEPOINT:
2343 lttng_create_tracepoint_event_notifier_if_missing(event_notifier_enabler);
2344 break;
2345
2346 case LTTNG_KERNEL_ABI_SYSCALL:
2347 lttng_create_syscall_event_notifier_if_missing(event_notifier_enabler);
2348 break;
2349
2350 default:
2351 WARN_ON_ONCE(1);
2352 break;
2353 }
2354}
2355
2356/*
2357 * Create event_notifiers associated with a event_notifier enabler (if not already present).
2358 */
2359static
2360int lttng_event_notifier_enabler_ref_event_notifiers(
2361 struct lttng_event_notifier_enabler *event_notifier_enabler)
2362{
2363 struct lttng_event_notifier_group *event_notifier_group = event_notifier_enabler->group;
2364 struct lttng_event_enabler_common *base_enabler = lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2365 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2366
2367 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_ABI_SYSCALL &&
2368 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL &&
2369 base_enabler->event_param.u.syscall.match == LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME &&
2370 !strcmp(base_enabler->event_param.name, "*")) {
2371
2372 int enabled = base_enabler->enabled;
2373 enum lttng_kernel_abi_syscall_entryexit entryexit = base_enabler->event_param.u.syscall.entryexit;
2374
2375 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2376 WRITE_ONCE(event_notifier_group->syscall_table.syscall_all_entry, enabled);
2377
2378 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2379 WRITE_ONCE(event_notifier_group->syscall_table.syscall_all_exit, enabled);
2380
2381 }
2382
2383 /* First ensure that probe event_notifiers are created for this enabler. */
2384 lttng_create_event_notifier_if_missing(event_notifier_enabler);
2385
2386 /* Link the created event_notifier with its associated enabler. */
2387 list_for_each_entry(event_notifier_priv, &event_notifier_group->event_notifiers_head, node) {
2388 struct lttng_kernel_event_notifier *event_notifier = event_notifier_priv->pub;
2389 struct lttng_enabler_ref *enabler_ref;
2390
2391 if (!lttng_event_notifier_enabler_match_event_notifier(event_notifier_enabler, event_notifier))
2392 continue;
2393
2394 enabler_ref = lttng_enabler_ref(&event_notifier_priv->parent.enablers_ref_head,
2395 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler));
2396 if (!enabler_ref) {
2397 /*
2398 * If no backward ref, create it.
2399 * Add backward ref from event_notifier to enabler.
2400 */
2401 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2402 if (!enabler_ref)
2403 return -ENOMEM;
2404
2405 enabler_ref->ref = lttng_event_notifier_enabler_as_enabler(
2406 event_notifier_enabler);
2407 list_add(&enabler_ref->node,
2408 &event_notifier_priv->parent.enablers_ref_head);
2409 }
2410
2411 /*
2412 * Link filter bytecodes if not linked yet.
2413 */
2414 lttng_enabler_link_bytecode(event_notifier_priv->parent.desc,
2415 lttng_static_ctx, &event_notifier_priv->parent.filter_bytecode_runtime_head,
2416 &lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->filter_bytecode_head);
2417
2418 /* Link capture bytecodes if not linked yet. */
2419 lttng_enabler_link_bytecode(event_notifier_priv->parent.desc,
2420 lttng_static_ctx, &event_notifier_priv->capture_bytecode_runtime_head,
2421 &event_notifier_enabler->capture_bytecode_head);
2422
2423 event_notifier_priv->num_captures = event_notifier_enabler->num_captures;
2424 }
2425 return 0;
2426}
2427
2428/*
2429 * Called at module load: connect the probe on all enablers matching
2430 * this event.
2431 * Called with sessions lock held.
2432 */
2433int lttng_fix_pending_events(void)
2434{
2435 struct lttng_kernel_session_private *session_priv;
2436
2437 list_for_each_entry(session_priv, &sessions, list)
2438 lttng_session_lazy_sync_event_enablers(session_priv->pub);
2439 return 0;
2440}
2441
2442static bool lttng_event_notifier_group_has_active_event_notifiers(
2443 struct lttng_event_notifier_group *event_notifier_group)
2444{
2445 struct lttng_event_notifier_enabler *event_notifier_enabler;
2446
2447 list_for_each_entry(event_notifier_enabler, &event_notifier_group->enablers_head,
2448 node) {
2449 if (event_notifier_enabler->parent.enabled)
2450 return true;
2451 }
2452 return false;
2453}
2454
2455bool lttng_event_notifier_active(void)
2456{
2457 struct lttng_event_notifier_group *event_notifier_group;
2458
2459 list_for_each_entry(event_notifier_group, &event_notifier_groups, node) {
2460 if (lttng_event_notifier_group_has_active_event_notifiers(event_notifier_group))
2461 return true;
2462 }
2463 return false;
2464}
2465
2466int lttng_fix_pending_event_notifiers(void)
2467{
2468 struct lttng_event_notifier_group *event_notifier_group;
2469
2470 list_for_each_entry(event_notifier_group, &event_notifier_groups, node)
2471 lttng_event_notifier_group_sync_enablers(event_notifier_group);
2472 return 0;
2473}
2474
2475struct lttng_event_recorder_enabler *lttng_event_recorder_enabler_create(
2476 enum lttng_enabler_format_type format_type,
2477 struct lttng_kernel_abi_event *event_param,
2478 struct lttng_kernel_channel_buffer *chan)
2479{
2480 struct lttng_event_recorder_enabler *event_enabler;
2481
2482 event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL);
2483 if (!event_enabler)
2484 return NULL;
2485 event_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_RECORDER;
2486 event_enabler->parent.format_type = format_type;
2487 INIT_LIST_HEAD(&event_enabler->parent.filter_bytecode_head);
2488 memcpy(&event_enabler->parent.event_param, event_param,
2489 sizeof(event_enabler->parent.event_param));
2490 event_enabler->chan = chan;
2491 /* ctx left NULL */
2492 event_enabler->parent.enabled = 0;
2493 return event_enabler;
2494}
2495
2496void lttng_event_enabler_session_add(struct lttng_kernel_session *session,
2497 struct lttng_event_recorder_enabler *event_enabler)
2498{
2499 mutex_lock(&sessions_mutex);
2500 list_add(&event_enabler->node, &session->priv->enablers_head);
2501 event_enabler->published = true;
2502 lttng_session_lazy_sync_event_enablers(session);
2503 mutex_unlock(&sessions_mutex);
2504}
2505
2506int lttng_event_enabler_enable(struct lttng_event_enabler_common *event_enabler)
2507{
2508 mutex_lock(&sessions_mutex);
2509 event_enabler->enabled = 1;
2510 lttng_event_enabler_sync(event_enabler);
2511 mutex_unlock(&sessions_mutex);
2512 return 0;
2513}
2514
2515int lttng_event_enabler_disable(struct lttng_event_enabler_common *event_enabler)
2516{
2517 mutex_lock(&sessions_mutex);
2518 event_enabler->enabled = 0;
2519 lttng_event_enabler_sync(event_enabler);
2520 mutex_unlock(&sessions_mutex);
2521 return 0;
2522}
2523
2524static
2525int lttng_enabler_attach_filter_bytecode(struct lttng_event_enabler_common *enabler,
2526 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2527{
2528 struct lttng_kernel_bytecode_node *bytecode_node;
2529 uint32_t bytecode_len;
2530 int ret;
2531
2532 ret = get_user(bytecode_len, &bytecode->len);
2533 if (ret)
2534 return ret;
2535 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2536 GFP_KERNEL);
2537 if (!bytecode_node)
2538 return -ENOMEM;
2539 ret = copy_from_user(&bytecode_node->bc, bytecode,
2540 sizeof(*bytecode) + bytecode_len);
2541 if (ret)
2542 goto error_free;
2543
2544 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_FILTER;
2545 bytecode_node->enabler = enabler;
2546 /* Enforce length based on allocated size */
2547 bytecode_node->bc.len = bytecode_len;
2548 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
2549
2550 return 0;
2551
2552error_free:
2553 lttng_kvfree(bytecode_node);
2554 return ret;
2555}
2556
2557int lttng_event_enabler_attach_filter_bytecode(struct lttng_event_enabler_common *event_enabler,
2558 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2559{
2560 int ret;
2561 ret = lttng_enabler_attach_filter_bytecode(event_enabler, bytecode);
2562 if (ret)
2563 goto error;
2564 lttng_event_enabler_sync(event_enabler);
2565 return 0;
2566
2567error:
2568 return ret;
2569}
2570
2571int lttng_event_add_callsite(struct lttng_kernel_event_common *event,
2572 struct lttng_kernel_abi_event_callsite __user *callsite)
2573{
2574
2575 switch (event->priv->instrumentation) {
2576 case LTTNG_KERNEL_ABI_UPROBE:
2577 return lttng_uprobes_event_add_callsite(event, callsite);
2578 default:
2579 return -EINVAL;
2580 }
2581}
2582
2583static
2584void lttng_enabler_destroy(struct lttng_event_enabler_common *enabler)
2585{
2586 struct lttng_kernel_bytecode_node *filter_node, *tmp_filter_node;
2587
2588 /* Destroy filter bytecode */
2589 list_for_each_entry_safe(filter_node, tmp_filter_node,
2590 &enabler->filter_bytecode_head, node) {
2591 lttng_kvfree(filter_node);
2592 }
2593}
2594
2595void lttng_event_enabler_destroy(struct lttng_event_enabler_common *event_enabler)
2596{
2597 switch (event_enabler->enabler_type) {
2598 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2599 {
2600 struct lttng_event_recorder_enabler *event_recorder_enabler =
2601 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2602
2603 lttng_enabler_destroy(event_enabler);
2604 if (event_recorder_enabler->published)
2605 list_del(&event_recorder_enabler->node);
2606 kfree(event_recorder_enabler);
2607 break;
2608 }
2609 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2610 {
2611 struct lttng_event_notifier_enabler *event_notifier_enabler =
2612 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2613
2614 list_del(&event_notifier_enabler->node);
2615 lttng_enabler_destroy(event_enabler);
2616 kfree(event_notifier_enabler);
2617 break;
2618 }
2619 default:
2620 WARN_ON_ONCE(1);
2621 }
2622}
2623
2624struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
2625 struct lttng_event_notifier_group *event_notifier_group,
2626 enum lttng_enabler_format_type format_type,
2627 struct lttng_kernel_abi_event_notifier *event_notifier_param)
2628{
2629 struct lttng_event_notifier_enabler *event_notifier_enabler;
2630
2631 event_notifier_enabler = kzalloc(sizeof(*event_notifier_enabler), GFP_KERNEL);
2632 if (!event_notifier_enabler)
2633 return NULL;
2634
2635 event_notifier_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_NOTIFIER;
2636 event_notifier_enabler->parent.format_type = format_type;
2637 INIT_LIST_HEAD(&event_notifier_enabler->parent.filter_bytecode_head);
2638 INIT_LIST_HEAD(&event_notifier_enabler->capture_bytecode_head);
2639
2640 event_notifier_enabler->error_counter_index = event_notifier_param->error_counter_index;
2641 event_notifier_enabler->num_captures = 0;
2642
2643 memcpy(&event_notifier_enabler->parent.event_param, &event_notifier_param->event,
2644 sizeof(event_notifier_enabler->parent.event_param));
2645
2646 event_notifier_enabler->parent.enabled = 0;
2647 event_notifier_enabler->parent.user_token = event_notifier_param->event.token;
2648 event_notifier_enabler->group = event_notifier_group;
2649
2650 mutex_lock(&sessions_mutex);
2651 list_add(&event_notifier_enabler->node, &event_notifier_enabler->group->enablers_head);
2652 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2653
2654 mutex_unlock(&sessions_mutex);
2655
2656 return event_notifier_enabler;
2657}
2658
2659int lttng_event_notifier_enabler_enable(
2660 struct lttng_event_notifier_enabler *event_notifier_enabler)
2661{
2662 mutex_lock(&sessions_mutex);
2663 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 1;
2664 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2665 mutex_unlock(&sessions_mutex);
2666 return 0;
2667}
2668
2669int lttng_event_notifier_enabler_disable(
2670 struct lttng_event_notifier_enabler *event_notifier_enabler)
2671{
2672 mutex_lock(&sessions_mutex);
2673 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 0;
2674 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2675 mutex_unlock(&sessions_mutex);
2676 return 0;
2677}
2678
2679int lttng_event_notifier_enabler_attach_capture_bytecode(
2680 struct lttng_event_notifier_enabler *event_notifier_enabler,
2681 struct lttng_kernel_abi_capture_bytecode __user *bytecode)
2682{
2683 struct lttng_kernel_bytecode_node *bytecode_node;
2684 struct lttng_event_enabler_common *enabler =
2685 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2686 uint32_t bytecode_len;
2687 int ret;
2688
2689 ret = get_user(bytecode_len, &bytecode->len);
2690 if (ret)
2691 return ret;
2692
2693 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2694 GFP_KERNEL);
2695 if (!bytecode_node)
2696 return -ENOMEM;
2697
2698 ret = copy_from_user(&bytecode_node->bc, bytecode,
2699 sizeof(*bytecode) + bytecode_len);
2700 if (ret)
2701 goto error_free;
2702
2703 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_CAPTURE;
2704 bytecode_node->enabler = enabler;
2705
2706 /* Enforce length based on allocated size */
2707 bytecode_node->bc.len = bytecode_len;
2708 list_add_tail(&bytecode_node->node, &event_notifier_enabler->capture_bytecode_head);
2709
2710 event_notifier_enabler->num_captures++;
2711
2712 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2713 goto end;
2714
2715error_free:
2716 lttng_kvfree(bytecode_node);
2717end:
2718 return ret;
2719}
2720
2721/*
2722 * lttng_session_sync_event_enablers should be called just before starting a
2723 * session.
2724 * Should be called with sessions mutex held.
2725 */
2726static
2727void lttng_session_sync_event_enablers(struct lttng_kernel_session *session)
2728{
2729 struct lttng_event_recorder_enabler *event_enabler;
2730 struct lttng_kernel_event_recorder_private *event_recorder_priv;
2731
2732 list_for_each_entry(event_enabler, &session->priv->enablers_head, node)
2733 lttng_event_enabler_ref_events(event_enabler);
2734 /*
2735 * For each event, if at least one of its enablers is enabled,
2736 * and its channel and session transient states are enabled, we
2737 * enable the event, else we disable it.
2738 */
2739 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
2740 struct lttng_kernel_event_recorder *event_recorder = event_recorder_priv->pub;
2741 struct lttng_enabler_ref *enabler_ref;
2742 struct lttng_kernel_bytecode_runtime *runtime;
2743 int enabled = 0, has_enablers_without_filter_bytecode = 0;
2744 int nr_filters = 0;
2745
2746 switch (event_recorder_priv->parent.instrumentation) {
2747 case LTTNG_KERNEL_ABI_TRACEPOINT:
2748 lttng_fallthrough;
2749 case LTTNG_KERNEL_ABI_SYSCALL:
2750 /* Enable events */
2751 list_for_each_entry(enabler_ref,
2752 &event_recorder_priv->parent.enablers_ref_head, node) {
2753 if (enabler_ref->ref->enabled) {
2754 enabled = 1;
2755 break;
2756 }
2757 }
2758 break;
2759
2760 default:
2761 /* Not handled with lazy sync. */
2762 continue;
2763 }
2764 /*
2765 * Enabled state is based on union of enablers, with
2766 * intesection of session and channel transient enable
2767 * states.
2768 */
2769 enabled = enabled && session->priv->tstate && event_recorder->chan->priv->parent.tstate;
2770
2771 WRITE_ONCE(event_recorder->parent.enabled, enabled);
2772 /*
2773 * Sync tracepoint registration with event enabled
2774 * state.
2775 */
2776 if (enabled) {
2777 register_event(event_recorder);
2778 } else {
2779 _lttng_event_unregister(event_recorder);
2780 }
2781
2782 /* Check if has enablers without bytecode enabled */
2783 list_for_each_entry(enabler_ref,
2784 &event_recorder_priv->parent.enablers_ref_head, node) {
2785 if (enabler_ref->ref->enabled
2786 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2787 has_enablers_without_filter_bytecode = 1;
2788 break;
2789 }
2790 }
2791 event_recorder_priv->parent.has_enablers_without_filter_bytecode =
2792 has_enablers_without_filter_bytecode;
2793
2794 /* Enable filters */
2795 list_for_each_entry(runtime,
2796 &event_recorder_priv->parent.filter_bytecode_runtime_head, node) {
2797 lttng_bytecode_sync_state(runtime);
2798 nr_filters++;
2799 }
2800 WRITE_ONCE(event_recorder_priv->parent.pub->eval_filter,
2801 !(has_enablers_without_filter_bytecode || !nr_filters));
2802 }
2803}
2804
2805/*
2806 * Apply enablers to session events, adding events to session if need
2807 * be. It is required after each modification applied to an active
2808 * session, and right before session "start".
2809 * "lazy" sync means we only sync if required.
2810 * Should be called with sessions mutex held.
2811 */
2812static
2813void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session)
2814{
2815 /* We can skip if session is not active */
2816 if (!session->active)
2817 return;
2818 lttng_session_sync_event_enablers(session);
2819}
2820
2821static
2822void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group)
2823{
2824 struct lttng_event_notifier_enabler *event_notifier_enabler;
2825 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2826
2827 list_for_each_entry(event_notifier_enabler, &event_notifier_group->enablers_head, node)
2828 lttng_event_notifier_enabler_ref_event_notifiers(event_notifier_enabler);
2829
2830 /*
2831 * For each event_notifier, if at least one of its enablers is enabled,
2832 * we enable the event_notifier, else we disable it.
2833 */
2834 list_for_each_entry(event_notifier_priv, &event_notifier_group->event_notifiers_head, node) {
2835 struct lttng_kernel_event_notifier *event_notifier = event_notifier_priv->pub;
2836 struct lttng_enabler_ref *enabler_ref;
2837 struct lttng_kernel_bytecode_runtime *runtime;
2838 int enabled = 0, has_enablers_without_filter_bytecode = 0;
2839 int nr_filters = 0, nr_captures = 0;
2840
2841 switch (event_notifier_priv->parent.instrumentation) {
2842 case LTTNG_KERNEL_ABI_TRACEPOINT:
2843 lttng_fallthrough;
2844 case LTTNG_KERNEL_ABI_SYSCALL:
2845 /* Enable event_notifiers */
2846 list_for_each_entry(enabler_ref,
2847 &event_notifier_priv->parent.enablers_ref_head, node) {
2848 if (enabler_ref->ref->enabled) {
2849 enabled = 1;
2850 break;
2851 }
2852 }
2853 break;
2854
2855 default:
2856 /* Not handled with sync. */
2857 continue;
2858 }
2859
2860 WRITE_ONCE(event_notifier->parent.enabled, enabled);
2861 /*
2862 * Sync tracepoint registration with event_notifier enabled
2863 * state.
2864 */
2865 if (enabled) {
2866 if (!event_notifier_priv->parent.registered)
2867 register_event_notifier(event_notifier);
2868 } else {
2869 if (event_notifier_priv->parent.registered)
2870 _lttng_event_notifier_unregister(event_notifier);
2871 }
2872
2873 /* Check if has enablers without bytecode enabled */
2874 list_for_each_entry(enabler_ref,
2875 &event_notifier_priv->parent.enablers_ref_head, node) {
2876 if (enabler_ref->ref->enabled
2877 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2878 has_enablers_without_filter_bytecode = 1;
2879 break;
2880 }
2881 }
2882 event_notifier_priv->parent.has_enablers_without_filter_bytecode =
2883 has_enablers_without_filter_bytecode;
2884
2885 /* Enable filters */
2886 list_for_each_entry(runtime,
2887 &event_notifier_priv->parent.filter_bytecode_runtime_head, node) {
2888 lttng_bytecode_sync_state(runtime);
2889 nr_filters++;
2890 }
2891 WRITE_ONCE(event_notifier_priv->parent.pub->eval_filter,
2892 !(has_enablers_without_filter_bytecode || !nr_filters));
2893
2894 /* Enable captures */
2895 list_for_each_entry(runtime,
2896 &event_notifier_priv->capture_bytecode_runtime_head, node) {
2897 lttng_bytecode_sync_state(runtime);
2898 nr_captures++;
2899 }
2900 WRITE_ONCE(event_notifier->eval_capture, !!nr_captures);
2901 }
2902}
2903
2904static
2905void lttng_event_enabler_sync(struct lttng_event_enabler_common *event_enabler)
2906{
2907 switch (event_enabler->enabler_type) {
2908 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2909 {
2910 struct lttng_event_recorder_enabler *event_recorder_enabler =
2911 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2912 lttng_session_lazy_sync_event_enablers(event_recorder_enabler->chan->parent.session);
2913 break;
2914 }
2915 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2916 {
2917 struct lttng_event_notifier_enabler *event_notifier_enabler =
2918 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2919 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2920 break;
2921 }
2922 default:
2923 WARN_ON_ONCE(1);
2924 }
2925}
2926
2927/*
2928 * Serialize at most one packet worth of metadata into a metadata
2929 * channel.
2930 * We grab the metadata cache mutex to get exclusive access to our metadata
2931 * buffer and to the metadata cache. Exclusive access to the metadata buffer
2932 * allows us to do racy operations such as looking for remaining space left in
2933 * packet and write, since mutual exclusion protects us from concurrent writes.
2934 * Mutual exclusion on the metadata cache allow us to read the cache content
2935 * without racing against reallocation of the cache by updates.
2936 * Returns the number of bytes written in the channel, 0 if no data
2937 * was written and a negative value on error.
2938 */
2939int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
2940 struct lttng_kernel_ring_buffer_channel *chan, bool *coherent)
2941{
2942 struct lttng_kernel_ring_buffer_ctx ctx;
2943 int ret = 0;
2944 size_t len, reserve_len;
2945
2946 /*
2947 * Ensure we support mutiple get_next / put sequences followed by
2948 * put_next. The metadata cache lock protects reading the metadata
2949 * cache. It can indeed be read concurrently by "get_next_subbuf" and
2950 * "flush" operations on the buffer invoked by different processes.
2951 * Moreover, since the metadata cache memory can be reallocated, we
2952 * need to have exclusive access against updates even though we only
2953 * read it.
2954 */
2955 mutex_lock(&stream->metadata_cache->lock);
2956 WARN_ON(stream->metadata_in < stream->metadata_out);
2957 if (stream->metadata_in != stream->metadata_out)
2958 goto end;
2959
2960 /* Metadata regenerated, change the version. */
2961 if (stream->metadata_cache->version != stream->version)
2962 stream->version = stream->metadata_cache->version;
2963
2964 len = stream->metadata_cache->metadata_written -
2965 stream->metadata_in;
2966 if (!len)
2967 goto end;
2968 reserve_len = min_t(size_t,
2969 stream->transport->ops.priv->packet_avail_size(chan),
2970 len);
2971 lib_ring_buffer_ctx_init(&ctx, chan, reserve_len,
2972 sizeof(char), NULL);
2973 /*
2974 * If reservation failed, return an error to the caller.
2975 */
2976 ret = stream->transport->ops.event_reserve(&ctx);
2977 if (ret != 0) {
2978 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
2979 stream->coherent = false;
2980 goto end;
2981 }
2982 stream->transport->ops.event_write(&ctx,
2983 stream->metadata_cache->data + stream->metadata_in,
2984 reserve_len, 1);
2985 stream->transport->ops.event_commit(&ctx);
2986 stream->metadata_in += reserve_len;
2987 if (reserve_len < len)
2988 stream->coherent = false;
2989 else
2990 stream->coherent = true;
2991 ret = reserve_len;
2992
2993end:
2994 if (coherent)
2995 *coherent = stream->coherent;
2996 mutex_unlock(&stream->metadata_cache->lock);
2997 return ret;
2998}
2999
3000static
3001void lttng_metadata_begin(struct lttng_kernel_session *session)
3002{
3003 if (atomic_inc_return(&session->priv->metadata_cache->producing) == 1)
3004 mutex_lock(&session->priv->metadata_cache->lock);
3005}
3006
3007static
3008void lttng_metadata_end(struct lttng_kernel_session *session)
3009{
3010 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
3011 if (atomic_dec_return(&session->priv->metadata_cache->producing) == 0) {
3012 struct lttng_metadata_stream *stream;
3013
3014 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list)
3015 wake_up_interruptible(&stream->read_wait);
3016 mutex_unlock(&session->priv->metadata_cache->lock);
3017 }
3018}
3019
3020/*
3021 * Write the metadata to the metadata cache.
3022 * Must be called with sessions_mutex held.
3023 * The metadata cache lock protects us from concurrent read access from
3024 * thread outputting metadata content to ring buffer.
3025 * The content of the printf is printed as a single atomic metadata
3026 * transaction.
3027 */
3028int lttng_metadata_printf(struct lttng_kernel_session *session,
3029 const char *fmt, ...)
3030{
3031 char *str;
3032 size_t len;
3033 va_list ap;
3034
3035 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
3036
3037 va_start(ap, fmt);
3038 str = kvasprintf(GFP_KERNEL, fmt, ap);
3039 va_end(ap);
3040 if (!str)
3041 return -ENOMEM;
3042
3043 len = strlen(str);
3044 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
3045 if (session->priv->metadata_cache->metadata_written + len >
3046 session->priv->metadata_cache->cache_alloc) {
3047 char *tmp_cache_realloc;
3048 unsigned int tmp_cache_alloc_size;
3049
3050 tmp_cache_alloc_size = max_t(unsigned int,
3051 session->priv->metadata_cache->cache_alloc + len,
3052 session->priv->metadata_cache->cache_alloc << 1);
3053 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
3054 if (!tmp_cache_realloc)
3055 goto err;
3056 if (session->priv->metadata_cache->data) {
3057 memcpy(tmp_cache_realloc,
3058 session->priv->metadata_cache->data,
3059 session->priv->metadata_cache->cache_alloc);
3060 vfree(session->priv->metadata_cache->data);
3061 }
3062
3063 session->priv->metadata_cache->cache_alloc = tmp_cache_alloc_size;
3064 session->priv->metadata_cache->data = tmp_cache_realloc;
3065 }
3066 memcpy(session->priv->metadata_cache->data +
3067 session->priv->metadata_cache->metadata_written,
3068 str, len);
3069 session->priv->metadata_cache->metadata_written += len;
3070 kfree(str);
3071
3072 return 0;
3073
3074err:
3075 kfree(str);
3076 return -ENOMEM;
3077}
3078
3079static
3080int print_tabs(struct lttng_kernel_session *session, size_t nesting)
3081{
3082 size_t i;
3083
3084 for (i = 0; i < nesting; i++) {
3085 int ret;
3086
3087 ret = lttng_metadata_printf(session, " ");
3088 if (ret) {
3089 return ret;
3090 }
3091 }
3092 return 0;
3093}
3094
3095static
3096int lttng_field_name_statedump(struct lttng_kernel_session *session,
3097 const struct lttng_kernel_event_field *field,
3098 size_t nesting)
3099{
3100 return lttng_metadata_printf(session, " _%s;\n", field->name);
3101}
3102
3103static
3104int _lttng_integer_type_statedump(struct lttng_kernel_session *session,
3105 const struct lttng_kernel_type_integer *type,
3106 enum lttng_kernel_string_encoding parent_encoding,
3107 size_t nesting)
3108{
3109 int ret;
3110
3111 ret = print_tabs(session, nesting);
3112 if (ret)
3113 return ret;
3114 ret = lttng_metadata_printf(session,
3115 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s }",
3116 type->size,
3117 type->alignment,
3118 type->signedness,
3119 (parent_encoding == lttng_kernel_string_encoding_none)
3120 ? "none"
3121 : (parent_encoding == lttng_kernel_string_encoding_UTF8)
3122 ? "UTF8"
3123 : "ASCII",
3124 type->base,
3125#if __BYTE_ORDER == __BIG_ENDIAN
3126 type->reverse_byte_order ? " byte_order = le;" : ""
3127#else
3128 type->reverse_byte_order ? " byte_order = be;" : ""
3129#endif
3130 );
3131 return ret;
3132}
3133
3134/*
3135 * Must be called with sessions_mutex held.
3136 */
3137static
3138int _lttng_struct_type_statedump(struct lttng_kernel_session *session,
3139 const struct lttng_kernel_type_struct *type,
3140 size_t nesting)
3141{
3142 const char *prev_field_name = NULL;
3143 int ret;
3144 uint32_t i, nr_fields;
3145 unsigned int alignment;
3146
3147 ret = print_tabs(session, nesting);
3148 if (ret)
3149 return ret;
3150 ret = lttng_metadata_printf(session,
3151 "struct {\n");
3152 if (ret)
3153 return ret;
3154 nr_fields = type->nr_fields;
3155 for (i = 0; i < nr_fields; i++) {
3156 const struct lttng_kernel_event_field *iter_field;
3157
3158 iter_field = type->fields[i];
3159 ret = _lttng_field_statedump(session, iter_field, nesting + 1, &prev_field_name);
3160 if (ret)
3161 return ret;
3162 }
3163 ret = print_tabs(session, nesting);
3164 if (ret)
3165 return ret;
3166 alignment = type->alignment;
3167 if (alignment) {
3168 ret = lttng_metadata_printf(session,
3169 "} align(%u)",
3170 alignment);
3171 } else {
3172 ret = lttng_metadata_printf(session,
3173 "}");
3174 }
3175 return ret;
3176}
3177
3178/*
3179 * Must be called with sessions_mutex held.
3180 */
3181static
3182int _lttng_struct_field_statedump(struct lttng_kernel_session *session,
3183 const struct lttng_kernel_event_field *field,
3184 size_t nesting)
3185{
3186 int ret;
3187
3188 ret = _lttng_struct_type_statedump(session,
3189 lttng_kernel_get_type_struct(field->type), nesting);
3190 if (ret)
3191 return ret;
3192 return lttng_field_name_statedump(session, field, nesting);
3193}
3194
3195/*
3196 * Must be called with sessions_mutex held.
3197 */
3198static
3199int _lttng_variant_type_statedump(struct lttng_kernel_session *session,
3200 const struct lttng_kernel_type_variant *type,
3201 size_t nesting,
3202 const char *prev_field_name)
3203{
3204 const char *tag_name;
3205 int ret;
3206 uint32_t i, nr_choices;
3207
3208 tag_name = type->tag_name;
3209 if (!tag_name)
3210 tag_name = prev_field_name;
3211 if (!tag_name)
3212 return -EINVAL;
3213 /*
3214 * CTF 1.8 does not allow expressing nonzero variant alignment in a nestable way.
3215 */
3216 if (type->alignment != 0)
3217 return -EINVAL;
3218 ret = print_tabs(session, nesting);
3219 if (ret)
3220 return ret;
3221 ret = lttng_metadata_printf(session,
3222 "variant <_%s> {\n",
3223 tag_name);
3224 if (ret)
3225 return ret;
3226 nr_choices = type->nr_choices;
3227 for (i = 0; i < nr_choices; i++) {
3228 const struct lttng_kernel_event_field *iter_field;
3229
3230 iter_field = type->choices[i];
3231 ret = _lttng_field_statedump(session, iter_field, nesting + 1, NULL);
3232 if (ret)
3233 return ret;
3234 }
3235 ret = print_tabs(session, nesting);
3236 if (ret)
3237 return ret;
3238 ret = lttng_metadata_printf(session,
3239 "}");
3240 return ret;
3241}
3242
3243/*
3244 * Must be called with sessions_mutex held.
3245 */
3246static
3247int _lttng_variant_field_statedump(struct lttng_kernel_session *session,
3248 const struct lttng_kernel_event_field *field,
3249 size_t nesting,
3250 const char *prev_field_name)
3251{
3252 int ret;
3253
3254 ret = _lttng_variant_type_statedump(session,
3255 lttng_kernel_get_type_variant(field->type), nesting,
3256 prev_field_name);
3257 if (ret)
3258 return ret;
3259 return lttng_field_name_statedump(session, field, nesting);
3260}
3261
3262/*
3263 * Must be called with sessions_mutex held.
3264 */
3265static
3266int _lttng_array_field_statedump(struct lttng_kernel_session *session,
3267 const struct lttng_kernel_event_field *field,
3268 size_t nesting)
3269{
3270 int ret;
3271 const struct lttng_kernel_type_array *array_type;
3272 const struct lttng_kernel_type_common *elem_type;
3273
3274 array_type = lttng_kernel_get_type_array(field->type);
3275 WARN_ON_ONCE(!array_type);
3276
3277 if (array_type->alignment) {
3278 ret = print_tabs(session, nesting);
3279 if (ret)
3280 return ret;
3281 ret = lttng_metadata_printf(session,
3282 "struct { } align(%u) _%s_padding;\n",
3283 array_type->alignment * CHAR_BIT,
3284 field->name);
3285 if (ret)
3286 return ret;
3287 }
3288 /*
3289 * Nested compound types: Only array of structures and variants are
3290 * currently supported.
3291 */
3292 elem_type = array_type->elem_type;
3293 switch (elem_type->type) {
3294 case lttng_kernel_type_integer:
3295 case lttng_kernel_type_struct:
3296 case lttng_kernel_type_variant:
3297 ret = _lttng_type_statedump(session, elem_type,
3298 array_type->encoding, nesting);
3299 if (ret)
3300 return ret;
3301 break;
3302
3303 default:
3304 return -EINVAL;
3305 }
3306 ret = lttng_metadata_printf(session,
3307 " _%s[%u];\n",
3308 field->name,
3309 array_type->length);
3310 return ret;
3311}
3312
3313/*
3314 * Must be called with sessions_mutex held.
3315 */
3316static
3317int _lttng_sequence_field_statedump(struct lttng_kernel_session *session,
3318 const struct lttng_kernel_event_field *field,
3319 size_t nesting,
3320 const char *prev_field_name)
3321{
3322 int ret;
3323 const char *length_name;
3324 const struct lttng_kernel_type_sequence *sequence_type;
3325 const struct lttng_kernel_type_common *elem_type;
3326
3327 sequence_type = lttng_kernel_get_type_sequence(field->type);
3328 WARN_ON_ONCE(!sequence_type);
3329
3330 length_name = sequence_type->length_name;
3331 if (!length_name)
3332 length_name = prev_field_name;
3333 if (!length_name)
3334 return -EINVAL;
3335
3336 if (sequence_type->alignment) {
3337 ret = print_tabs(session, nesting);
3338 if (ret)
3339 return ret;
3340 ret = lttng_metadata_printf(session,
3341 "struct { } align(%u) _%s_padding;\n",
3342 sequence_type->alignment * CHAR_BIT,
3343 field->name);
3344 if (ret)
3345 return ret;
3346 }
3347
3348 /*
3349 * Nested compound types: Only array of structures and variants are
3350 * currently supported.
3351 */
3352 elem_type = sequence_type->elem_type;
3353 switch (elem_type->type) {
3354 case lttng_kernel_type_integer:
3355 case lttng_kernel_type_struct:
3356 case lttng_kernel_type_variant:
3357 ret = _lttng_type_statedump(session, elem_type,
3358 sequence_type->encoding, nesting);
3359 if (ret)
3360 return ret;
3361 break;
3362
3363 default:
3364 return -EINVAL;
3365 }
3366 ret = lttng_metadata_printf(session,
3367 " _%s[ _%s ];\n",
3368 field->name,
3369 length_name);
3370 return ret;
3371}
3372
3373/*
3374 * Must be called with sessions_mutex held.
3375 */
3376static
3377int _lttng_enum_type_statedump(struct lttng_kernel_session *session,
3378 const struct lttng_kernel_type_enum *type,
3379 size_t nesting)
3380{
3381 const struct lttng_kernel_enum_desc *enum_desc;
3382 const struct lttng_kernel_type_common *container_type;
3383 int ret;
3384 unsigned int i, nr_entries;
3385
3386 container_type = type->container_type;
3387 if (container_type->type != lttng_kernel_type_integer) {
3388 ret = -EINVAL;
3389 goto end;
3390 }
3391 enum_desc = type->desc;
3392 nr_entries = enum_desc->nr_entries;
3393
3394 ret = print_tabs(session, nesting);
3395 if (ret)
3396 goto end;
3397 ret = lttng_metadata_printf(session, "enum : ");
3398 if (ret)
3399 goto end;
3400 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(container_type),
3401 lttng_kernel_string_encoding_none, 0);
3402 if (ret)
3403 goto end;
3404 ret = lttng_metadata_printf(session, " {\n");
3405 if (ret)
3406 goto end;
3407 /* Dump all entries */
3408 for (i = 0; i < nr_entries; i++) {
3409 const struct lttng_kernel_enum_entry *entry = enum_desc->entries[i];
3410 int j, len;
3411
3412 ret = print_tabs(session, nesting + 1);
3413 if (ret)
3414 goto end;
3415 ret = lttng_metadata_printf(session,
3416 "\"");
3417 if (ret)
3418 goto end;
3419 len = strlen(entry->string);
3420 /* Escape the character '"' */
3421 for (j = 0; j < len; j++) {
3422 char c = entry->string[j];
3423
3424 switch (c) {
3425 case '"':
3426 ret = lttng_metadata_printf(session,
3427 "\\\"");
3428 break;
3429 case '\\':
3430 ret = lttng_metadata_printf(session,
3431 "\\\\");
3432 break;
3433 default:
3434 ret = lttng_metadata_printf(session,
3435 "%c", c);
3436 break;
3437 }
3438 if (ret)
3439 goto end;
3440 }
3441 ret = lttng_metadata_printf(session, "\"");
3442 if (ret)
3443 goto end;
3444
3445 if (entry->options.is_auto) {
3446 ret = lttng_metadata_printf(session, ",\n");
3447 if (ret)
3448 goto end;
3449 } else {
3450 ret = lttng_metadata_printf(session,
3451 " = ");
3452 if (ret)
3453 goto end;
3454 if (entry->start.signedness)
3455 ret = lttng_metadata_printf(session,
3456 "%lld", (long long) entry->start.value);
3457 else
3458 ret = lttng_metadata_printf(session,
3459 "%llu", entry->start.value);
3460 if (ret)
3461 goto end;
3462 if (entry->start.signedness == entry->end.signedness &&
3463 entry->start.value
3464 == entry->end.value) {
3465 ret = lttng_metadata_printf(session,
3466 ",\n");
3467 } else {
3468 if (entry->end.signedness) {
3469 ret = lttng_metadata_printf(session,
3470 " ... %lld,\n",
3471 (long long) entry->end.value);
3472 } else {
3473 ret = lttng_metadata_printf(session,
3474 " ... %llu,\n",
3475 entry->end.value);
3476 }
3477 }
3478 if (ret)
3479 goto end;
3480 }
3481 }
3482 ret = print_tabs(session, nesting);
3483 if (ret)
3484 goto end;
3485 ret = lttng_metadata_printf(session, "}");
3486end:
3487 return ret;
3488}
3489
3490/*
3491 * Must be called with sessions_mutex held.
3492 */
3493static
3494int _lttng_enum_field_statedump(struct lttng_kernel_session *session,
3495 const struct lttng_kernel_event_field *field,
3496 size_t nesting)
3497{
3498 int ret;
3499 const struct lttng_kernel_type_enum *enum_type;
3500
3501 enum_type = lttng_kernel_get_type_enum(field->type);
3502 WARN_ON_ONCE(!enum_type);
3503 ret = _lttng_enum_type_statedump(session, enum_type, nesting);
3504 if (ret)
3505 return ret;
3506 return lttng_field_name_statedump(session, field, nesting);
3507}
3508
3509static
3510int _lttng_integer_field_statedump(struct lttng_kernel_session *session,
3511 const struct lttng_kernel_event_field *field,
3512 size_t nesting)
3513{
3514 int ret;
3515
3516 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(field->type),
3517 lttng_kernel_string_encoding_none, nesting);
3518 if (ret)
3519 return ret;
3520 return lttng_field_name_statedump(session, field, nesting);
3521}
3522
3523static
3524int _lttng_string_type_statedump(struct lttng_kernel_session *session,
3525 const struct lttng_kernel_type_string *type,
3526 size_t nesting)
3527{
3528 int ret;
3529
3530 /* Default encoding is UTF8 */
3531 ret = print_tabs(session, nesting);
3532 if (ret)
3533 return ret;
3534 ret = lttng_metadata_printf(session,
3535 "string%s",
3536 type->encoding == lttng_kernel_string_encoding_ASCII ?
3537 " { encoding = ASCII; }" : "");
3538 return ret;
3539}
3540
3541static
3542int _lttng_string_field_statedump(struct lttng_kernel_session *session,
3543 const struct lttng_kernel_event_field *field,
3544 size_t nesting)
3545{
3546 const struct lttng_kernel_type_string *string_type;
3547 int ret;
3548
3549 string_type = lttng_kernel_get_type_string(field->type);
3550 WARN_ON_ONCE(!string_type);
3551 ret = _lttng_string_type_statedump(session, string_type, nesting);
3552 if (ret)
3553 return ret;
3554 return lttng_field_name_statedump(session, field, nesting);
3555}
3556
3557/*
3558 * Must be called with sessions_mutex held.
3559 */
3560static
3561int _lttng_type_statedump(struct lttng_kernel_session *session,
3562 const struct lttng_kernel_type_common *type,
3563 enum lttng_kernel_string_encoding parent_encoding,
3564 size_t nesting)
3565{
3566 int ret = 0;
3567
3568 switch (type->type) {
3569 case lttng_kernel_type_integer:
3570 ret = _lttng_integer_type_statedump(session,
3571 lttng_kernel_get_type_integer(type),
3572 parent_encoding, nesting);
3573 break;
3574 case lttng_kernel_type_enum:
3575 ret = _lttng_enum_type_statedump(session,
3576 lttng_kernel_get_type_enum(type),
3577 nesting);
3578 break;
3579 case lttng_kernel_type_string:
3580 ret = _lttng_string_type_statedump(session,
3581 lttng_kernel_get_type_string(type),
3582 nesting);
3583 break;
3584 case lttng_kernel_type_struct:
3585 ret = _lttng_struct_type_statedump(session,
3586 lttng_kernel_get_type_struct(type),
3587 nesting);
3588 break;
3589 case lttng_kernel_type_variant:
3590 ret = _lttng_variant_type_statedump(session,
3591 lttng_kernel_get_type_variant(type),
3592 nesting, NULL);
3593 break;
3594
3595 /* Nested arrays and sequences are not supported yet. */
3596 case lttng_kernel_type_array:
3597 case lttng_kernel_type_sequence:
3598 default:
3599 WARN_ON_ONCE(1);
3600 return -EINVAL;
3601 }
3602 return ret;
3603}
3604
3605/*
3606 * Must be called with sessions_mutex held.
3607 */
3608static
3609int _lttng_field_statedump(struct lttng_kernel_session *session,
3610 const struct lttng_kernel_event_field *field,
3611 size_t nesting,
3612 const char **prev_field_name_p)
3613{
3614 const char *prev_field_name = NULL;
3615 int ret = 0;
3616
3617 if (prev_field_name_p)
3618 prev_field_name = *prev_field_name_p;
3619 switch (field->type->type) {
3620 case lttng_kernel_type_integer:
3621 ret = _lttng_integer_field_statedump(session, field, nesting);
3622 break;
3623 case lttng_kernel_type_enum:
3624 ret = _lttng_enum_field_statedump(session, field, nesting);
3625 break;
3626 case lttng_kernel_type_string:
3627 ret = _lttng_string_field_statedump(session, field, nesting);
3628 break;
3629 case lttng_kernel_type_struct:
3630 ret = _lttng_struct_field_statedump(session, field, nesting);
3631 break;
3632 case lttng_kernel_type_array:
3633 ret = _lttng_array_field_statedump(session, field, nesting);
3634 break;
3635 case lttng_kernel_type_sequence:
3636 ret = _lttng_sequence_field_statedump(session, field, nesting, prev_field_name);
3637 break;
3638 case lttng_kernel_type_variant:
3639 ret = _lttng_variant_field_statedump(session, field, nesting, prev_field_name);
3640 break;
3641
3642 default:
3643 WARN_ON_ONCE(1);
3644 return -EINVAL;
3645 }
3646 if (prev_field_name_p)
3647 *prev_field_name_p = field->name;
3648 return ret;
3649}
3650
3651static
3652int _lttng_context_metadata_statedump(struct lttng_kernel_session *session,
3653 struct lttng_kernel_ctx *ctx)
3654{
3655 const char *prev_field_name = NULL;
3656 int ret = 0;
3657 int i;
3658
3659 if (!ctx)
3660 return 0;
3661 for (i = 0; i < ctx->nr_fields; i++) {
3662 const struct lttng_kernel_ctx_field *field = &ctx->fields[i];
3663
3664 ret = _lttng_field_statedump(session, field->event_field, 2, &prev_field_name);
3665 if (ret)
3666 return ret;
3667 }
3668 return ret;
3669}
3670
3671static
3672int _lttng_fields_metadata_statedump(struct lttng_kernel_session *session,
3673 struct lttng_kernel_event_recorder *event_recorder)
3674{
3675 const char *prev_field_name = NULL;
3676 const struct lttng_kernel_event_desc *desc = event_recorder->priv->parent.desc;
3677 int ret = 0;
3678 int i;
3679
3680 for (i = 0; i < desc->tp_class->nr_fields; i++) {
3681 const struct lttng_kernel_event_field *field = desc->tp_class->fields[i];
3682
3683 ret = _lttng_field_statedump(session, field, 2, &prev_field_name);
3684 if (ret)
3685 return ret;
3686 }
3687 return ret;
3688}
3689
3690/*
3691 * Must be called with sessions_mutex held.
3692 * The entire event metadata is printed as a single atomic metadata
3693 * transaction.
3694 */
3695static
3696int _lttng_event_metadata_statedump(struct lttng_kernel_session *session,
3697 struct lttng_kernel_channel_buffer *chan,
3698 struct lttng_kernel_event_recorder *event_recorder)
3699{
3700 int ret = 0;
3701
3702 if (event_recorder->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3703 return 0;
3704 if (chan->priv->channel_type == METADATA_CHANNEL)
3705 return 0;
3706
3707 lttng_metadata_begin(session);
3708
3709 ret = lttng_metadata_printf(session,
3710 "event {\n"
3711 " name = \"%s\";\n"
3712 " id = %u;\n"
3713 " stream_id = %u;\n",
3714 event_recorder->priv->parent.desc->event_name,
3715 event_recorder->priv->id,
3716 event_recorder->chan->priv->id);
3717 if (ret)
3718 goto end;
3719
3720 ret = lttng_metadata_printf(session,
3721 " fields := struct {\n"
3722 );
3723 if (ret)
3724 goto end;
3725
3726 ret = _lttng_fields_metadata_statedump(session, event_recorder);
3727 if (ret)
3728 goto end;
3729
3730 /*
3731 * LTTng space reservation can only reserve multiples of the
3732 * byte size.
3733 */
3734 ret = lttng_metadata_printf(session,
3735 " };\n"
3736 "};\n\n");
3737 if (ret)
3738 goto end;
3739
3740 event_recorder->priv->metadata_dumped = 1;
3741end:
3742 lttng_metadata_end(session);
3743 return ret;
3744
3745}
3746
3747/*
3748 * Must be called with sessions_mutex held.
3749 * The entire channel metadata is printed as a single atomic metadata
3750 * transaction.
3751 */
3752static
3753int _lttng_channel_metadata_statedump(struct lttng_kernel_session *session,
3754 struct lttng_kernel_channel_buffer *chan)
3755{
3756 int ret = 0;
3757
3758 if (chan->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3759 return 0;
3760
3761 if (chan->priv->channel_type == METADATA_CHANNEL)
3762 return 0;
3763
3764 lttng_metadata_begin(session);
3765
3766 WARN_ON_ONCE(!chan->priv->header_type);
3767 ret = lttng_metadata_printf(session,
3768 "stream {\n"
3769 " id = %u;\n"
3770 " event.header := %s;\n"
3771 " packet.context := struct packet_context;\n",
3772 chan->priv->id,
3773 chan->priv->header_type == 1 ? "struct event_header_compact" :
3774 "struct event_header_large");
3775 if (ret)
3776 goto end;
3777
3778 if (chan->priv->ctx) {
3779 ret = lttng_metadata_printf(session,
3780 " event.context := struct {\n");
3781 if (ret)
3782 goto end;
3783 }
3784 ret = _lttng_context_metadata_statedump(session, chan->priv->ctx);
3785 if (ret)
3786 goto end;
3787 if (chan->priv->ctx) {
3788 ret = lttng_metadata_printf(session,
3789 " };\n");
3790 if (ret)
3791 goto end;
3792 }
3793
3794 ret = lttng_metadata_printf(session,
3795 "};\n\n");
3796
3797 chan->priv->metadata_dumped = 1;
3798end:
3799 lttng_metadata_end(session);
3800 return ret;
3801}
3802
3803/*
3804 * Must be called with sessions_mutex held.
3805 */
3806static
3807int _lttng_stream_packet_context_declare(struct lttng_kernel_session *session)
3808{
3809 return lttng_metadata_printf(session,
3810 "struct packet_context {\n"
3811 " uint64_clock_monotonic_t timestamp_begin;\n"
3812 " uint64_clock_monotonic_t timestamp_end;\n"
3813 " uint64_t content_size;\n"
3814 " uint64_t packet_size;\n"
3815 " uint64_t packet_seq_num;\n"
3816 " unsigned long events_discarded;\n"
3817 " uint32_t cpu_id;\n"
3818 "};\n\n"
3819 );
3820}
3821
3822/*
3823 * Compact header:
3824 * id: range: 0 - 30.
3825 * id 31 is reserved to indicate an extended header.
3826 *
3827 * Large header:
3828 * id: range: 0 - 65534.
3829 * id 65535 is reserved to indicate an extended header.
3830 *
3831 * Must be called with sessions_mutex held.
3832 */
3833static
3834int _lttng_event_header_declare(struct lttng_kernel_session *session)
3835{
3836 return lttng_metadata_printf(session,
3837 "struct event_header_compact {\n"
3838 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
3839 " variant <id> {\n"
3840 " struct {\n"
3841 " uint27_clock_monotonic_t timestamp;\n"
3842 " } compact;\n"
3843 " struct {\n"
3844 " uint32_t id;\n"
3845 " uint64_clock_monotonic_t timestamp;\n"
3846 " } extended;\n"
3847 " } v;\n"
3848 "} align(%u);\n"
3849 "\n"
3850 "struct event_header_large {\n"
3851 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
3852 " variant <id> {\n"
3853 " struct {\n"
3854 " uint32_clock_monotonic_t timestamp;\n"
3855 " } compact;\n"
3856 " struct {\n"
3857 " uint32_t id;\n"
3858 " uint64_clock_monotonic_t timestamp;\n"
3859 " } extended;\n"
3860 " } v;\n"
3861 "} align(%u);\n\n",
3862 lttng_alignof(uint32_t) * CHAR_BIT,
3863 lttng_alignof(uint16_t) * CHAR_BIT
3864 );
3865}
3866
3867 /*
3868 * Approximation of NTP time of day to clock monotonic correlation,
3869 * taken at start of trace.
3870 * Yes, this is only an approximation. Yes, we can (and will) do better
3871 * in future versions.
3872 * This function may return a negative offset. It may happen if the
3873 * system sets the REALTIME clock to 0 after boot.
3874 *
3875 * Use 64bit timespec on kernels that have it, this makes 32bit arch
3876 * y2038 compliant.
3877 */
3878static
3879int64_t measure_clock_offset(void)
3880{
3881 uint64_t monotonic_avg, monotonic[2], realtime;
3882 uint64_t tcf = trace_clock_freq();
3883 int64_t offset;
3884 unsigned long flags;
3885#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3886 struct timespec64 rts = { 0, 0 };
3887#else
3888 struct timespec rts = { 0, 0 };
3889#endif
3890
3891 /* Disable interrupts to increase correlation precision. */
3892 local_irq_save(flags);
3893 monotonic[0] = trace_clock_read64();
3894#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3895 ktime_get_real_ts64(&rts);
3896#else
3897 getnstimeofday(&rts);
3898#endif
3899 monotonic[1] = trace_clock_read64();
3900 local_irq_restore(flags);
3901
3902 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
3903 realtime = (uint64_t) rts.tv_sec * tcf;
3904 if (tcf == NSEC_PER_SEC) {
3905 realtime += rts.tv_nsec;
3906 } else {
3907 uint64_t n = rts.tv_nsec * tcf;
3908
3909 do_div(n, NSEC_PER_SEC);
3910 realtime += n;
3911 }
3912 offset = (int64_t) realtime - monotonic_avg;
3913 return offset;
3914}
3915
3916static
3917int print_escaped_ctf_string(struct lttng_kernel_session *session, const char *string)
3918{
3919 int ret = 0;
3920 size_t i;
3921 char cur;
3922
3923 i = 0;
3924 cur = string[i];
3925 while (cur != '\0') {
3926 switch (cur) {
3927 case '\n':
3928 ret = lttng_metadata_printf(session, "%s", "\\n");
3929 break;
3930 case '\\':
3931 case '"':
3932 ret = lttng_metadata_printf(session, "%c", '\\');
3933 if (ret)
3934 goto error;
3935 /* We still print the current char */
3936 lttng_fallthrough;
3937 default:
3938 ret = lttng_metadata_printf(session, "%c", cur);
3939 break;
3940 }
3941
3942 if (ret)
3943 goto error;
3944
3945 cur = string[++i];
3946 }
3947error:
3948 return ret;
3949}
3950
3951static
3952int print_metadata_escaped_field(struct lttng_kernel_session *session, const char *field,
3953 const char *field_value)
3954{
3955 int ret;
3956
3957 ret = lttng_metadata_printf(session, " %s = \"", field);
3958 if (ret)
3959 goto error;
3960
3961 ret = print_escaped_ctf_string(session, field_value);
3962 if (ret)
3963 goto error;
3964
3965 ret = lttng_metadata_printf(session, "\";\n");
3966
3967error:
3968 return ret;
3969}
3970
3971/*
3972 * Output metadata into this session's metadata buffers.
3973 * Must be called with sessions_mutex held.
3974 */
3975static
3976int _lttng_session_metadata_statedump(struct lttng_kernel_session *session)
3977{
3978 unsigned char *uuid_c = session->priv->uuid.b;
3979 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
3980 const char *product_uuid;
3981 struct lttng_kernel_channel_buffer_private *chan_priv;
3982 struct lttng_kernel_event_recorder_private *event_recorder_priv;
3983 int ret = 0;
3984
3985 if (!LTTNG_READ_ONCE(session->active))
3986 return 0;
3987
3988 lttng_metadata_begin(session);
3989
3990 if (session->priv->metadata_dumped)
3991 goto skip_session;
3992
3993 snprintf(uuid_s, sizeof(uuid_s),
3994 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
3995 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
3996 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
3997 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
3998 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
3999
4000 ret = lttng_metadata_printf(session,
4001 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
4002 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
4003 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
4004 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
4005 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
4006 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
4007 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
4008 "\n"
4009 "trace {\n"
4010 " major = %u;\n"
4011 " minor = %u;\n"
4012 " uuid = \"%s\";\n"
4013 " byte_order = %s;\n"
4014 " packet.header := struct {\n"
4015 " uint32_t magic;\n"
4016 " uint8_t uuid[16];\n"
4017 " uint32_t stream_id;\n"
4018 " uint64_t stream_instance_id;\n"
4019 " };\n"
4020 "};\n\n",
4021 lttng_alignof(uint8_t) * CHAR_BIT,
4022 lttng_alignof(uint16_t) * CHAR_BIT,
4023 lttng_alignof(uint32_t) * CHAR_BIT,
4024 lttng_alignof(uint64_t) * CHAR_BIT,
4025 sizeof(unsigned long) * CHAR_BIT,
4026 lttng_alignof(unsigned long) * CHAR_BIT,
4027 CTF_SPEC_MAJOR,
4028 CTF_SPEC_MINOR,
4029 uuid_s,
4030#if __BYTE_ORDER == __BIG_ENDIAN
4031 "be"
4032#else
4033 "le"
4034#endif
4035 );
4036 if (ret)
4037 goto end;
4038
4039 ret = lttng_metadata_printf(session,
4040 "env {\n"
4041 " hostname = \"%s\";\n"
4042 " domain = \"kernel\";\n"
4043 " sysname = \"%s\";\n"
4044 " kernel_release = \"%s\";\n"
4045 " kernel_version = \"%s\";\n"
4046 " tracer_name = \"lttng-modules\";\n"
4047 " tracer_major = %d;\n"
4048 " tracer_minor = %d;\n"
4049 " tracer_patchlevel = %d;\n"
4050 " trace_buffering_scheme = \"global\";\n",
4051 current->nsproxy->uts_ns->name.nodename,
4052 utsname()->sysname,
4053 utsname()->release,
4054 utsname()->version,
4055 LTTNG_MODULES_MAJOR_VERSION,
4056 LTTNG_MODULES_MINOR_VERSION,
4057 LTTNG_MODULES_PATCHLEVEL_VERSION
4058 );
4059 if (ret)
4060 goto end;
4061
4062 ret = print_metadata_escaped_field(session, "trace_name", session->priv->name);
4063 if (ret)
4064 goto end;
4065 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
4066 session->priv->creation_time);
4067 if (ret)
4068 goto end;
4069
4070 /* Add the product UUID to the 'env' section */
4071 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
4072 if (product_uuid) {
4073 ret = lttng_metadata_printf(session,
4074 " product_uuid = \"%s\";\n",
4075 product_uuid
4076 );
4077 if (ret)
4078 goto end;
4079 }
4080
4081 /* Close the 'env' section */
4082 ret = lttng_metadata_printf(session, "};\n\n");
4083 if (ret)
4084 goto end;
4085
4086 ret = lttng_metadata_printf(session,
4087 "clock {\n"
4088 " name = \"%s\";\n",
4089 trace_clock_name()
4090 );
4091 if (ret)
4092 goto end;
4093
4094 if (!trace_clock_uuid(clock_uuid_s)) {
4095 ret = lttng_metadata_printf(session,
4096 " uuid = \"%s\";\n",
4097 clock_uuid_s
4098 );
4099 if (ret)
4100 goto end;
4101 }
4102
4103 ret = lttng_metadata_printf(session,
4104 " description = \"%s\";\n"
4105 " freq = %llu; /* Frequency, in Hz */\n"
4106 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
4107 " offset = %lld;\n"
4108 "};\n\n",
4109 trace_clock_description(),
4110 (unsigned long long) trace_clock_freq(),
4111 (long long) measure_clock_offset()
4112 );
4113 if (ret)
4114 goto end;
4115
4116 ret = lttng_metadata_printf(session,
4117 "typealias integer {\n"
4118 " size = 27; align = 1; signed = false;\n"
4119 " map = clock.%s.value;\n"
4120 "} := uint27_clock_monotonic_t;\n"
4121 "\n"
4122 "typealias integer {\n"
4123 " size = 32; align = %u; signed = false;\n"
4124 " map = clock.%s.value;\n"
4125 "} := uint32_clock_monotonic_t;\n"
4126 "\n"
4127 "typealias integer {\n"
4128 " size = 64; align = %u; signed = false;\n"
4129 " map = clock.%s.value;\n"
4130 "} := uint64_clock_monotonic_t;\n\n",
4131 trace_clock_name(),
4132 lttng_alignof(uint32_t) * CHAR_BIT,
4133 trace_clock_name(),
4134 lttng_alignof(uint64_t) * CHAR_BIT,
4135 trace_clock_name()
4136 );
4137 if (ret)
4138 goto end;
4139
4140 ret = _lttng_stream_packet_context_declare(session);
4141 if (ret)
4142 goto end;
4143
4144 ret = _lttng_event_header_declare(session);
4145 if (ret)
4146 goto end;
4147
4148skip_session:
4149 list_for_each_entry(chan_priv, &session->priv->chan, node) {
4150 ret = _lttng_channel_metadata_statedump(session, chan_priv->pub);
4151 if (ret)
4152 goto end;
4153 }
4154
4155 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
4156 ret = _lttng_event_metadata_statedump(session, event_recorder_priv->pub->chan,
4157 event_recorder_priv->pub);
4158 if (ret)
4159 goto end;
4160 }
4161 session->priv->metadata_dumped = 1;
4162end:
4163 lttng_metadata_end(session);
4164 return ret;
4165}
4166
4167/**
4168 * lttng_transport_register - LTT transport registration
4169 * @transport: transport structure
4170 *
4171 * Registers a transport which can be used as output to extract the data out of
4172 * LTTng. The module calling this registration function must ensure that no
4173 * trap-inducing code will be executed by the transport functions. E.g.
4174 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
4175 * is made visible to the transport function. This registration acts as a
4176 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
4177 * after its registration must it synchronize the TLBs.
4178 */
4179void lttng_transport_register(struct lttng_transport *transport)
4180{
4181 /*
4182 * Make sure no page fault can be triggered by the module about to be
4183 * registered. We deal with this here so we don't have to call
4184 * vmalloc_sync_mappings() in each module's init.
4185 */
4186 wrapper_vmalloc_sync_mappings();
4187
4188 mutex_lock(&sessions_mutex);
4189 list_add_tail(&transport->node, &lttng_transport_list);
4190 mutex_unlock(&sessions_mutex);
4191}
4192EXPORT_SYMBOL_GPL(lttng_transport_register);
4193
4194/**
4195 * lttng_transport_unregister - LTT transport unregistration
4196 * @transport: transport structure
4197 */
4198void lttng_transport_unregister(struct lttng_transport *transport)
4199{
4200 mutex_lock(&sessions_mutex);
4201 list_del(&transport->node);
4202 mutex_unlock(&sessions_mutex);
4203}
4204EXPORT_SYMBOL_GPL(lttng_transport_unregister);
4205
4206void lttng_counter_transport_register(struct lttng_counter_transport *transport)
4207{
4208 /*
4209 * Make sure no page fault can be triggered by the module about to be
4210 * registered. We deal with this here so we don't have to call
4211 * vmalloc_sync_mappings() in each module's init.
4212 */
4213 wrapper_vmalloc_sync_mappings();
4214
4215 mutex_lock(&sessions_mutex);
4216 list_add_tail(&transport->node, &lttng_counter_transport_list);
4217 mutex_unlock(&sessions_mutex);
4218}
4219EXPORT_SYMBOL_GPL(lttng_counter_transport_register);
4220
4221void lttng_counter_transport_unregister(struct lttng_counter_transport *transport)
4222{
4223 mutex_lock(&sessions_mutex);
4224 list_del(&transport->node);
4225 mutex_unlock(&sessions_mutex);
4226}
4227EXPORT_SYMBOL_GPL(lttng_counter_transport_unregister);
4228
4229#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0))
4230
4231enum cpuhp_state lttng_hp_prepare;
4232enum cpuhp_state lttng_hp_online;
4233
4234static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
4235{
4236 struct lttng_cpuhp_node *lttng_node;
4237
4238 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4239 switch (lttng_node->component) {
4240 case LTTNG_RING_BUFFER_FRONTEND:
4241 return 0;
4242 case LTTNG_RING_BUFFER_BACKEND:
4243 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
4244 case LTTNG_RING_BUFFER_ITER:
4245 return 0;
4246 case LTTNG_CONTEXT_PERF_COUNTERS:
4247 return 0;
4248 default:
4249 return -EINVAL;
4250 }
4251}
4252
4253static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
4254{
4255 struct lttng_cpuhp_node *lttng_node;
4256
4257 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4258 switch (lttng_node->component) {
4259 case LTTNG_RING_BUFFER_FRONTEND:
4260 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
4261 case LTTNG_RING_BUFFER_BACKEND:
4262 return 0;
4263 case LTTNG_RING_BUFFER_ITER:
4264 return 0;
4265 case LTTNG_CONTEXT_PERF_COUNTERS:
4266 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
4267 default:
4268 return -EINVAL;
4269 }
4270}
4271
4272static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
4273{
4274 struct lttng_cpuhp_node *lttng_node;
4275
4276 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4277 switch (lttng_node->component) {
4278 case LTTNG_RING_BUFFER_FRONTEND:
4279 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
4280 case LTTNG_RING_BUFFER_BACKEND:
4281 return 0;
4282 case LTTNG_RING_BUFFER_ITER:
4283 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
4284 case LTTNG_CONTEXT_PERF_COUNTERS:
4285 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
4286 default:
4287 return -EINVAL;
4288 }
4289}
4290
4291static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
4292{
4293 struct lttng_cpuhp_node *lttng_node;
4294
4295 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4296 switch (lttng_node->component) {
4297 case LTTNG_RING_BUFFER_FRONTEND:
4298 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
4299 case LTTNG_RING_BUFFER_BACKEND:
4300 return 0;
4301 case LTTNG_RING_BUFFER_ITER:
4302 return 0;
4303 case LTTNG_CONTEXT_PERF_COUNTERS:
4304 return 0;
4305 default:
4306 return -EINVAL;
4307 }
4308}
4309
4310static int __init lttng_init_cpu_hotplug(void)
4311{
4312 int ret;
4313
4314 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
4315 lttng_hotplug_prepare,
4316 lttng_hotplug_dead);
4317 if (ret < 0) {
4318 return ret;
4319 }
4320 lttng_hp_prepare = ret;
4321 lttng_rb_set_hp_prepare(ret);
4322
4323 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
4324 lttng_hotplug_online,
4325 lttng_hotplug_offline);
4326 if (ret < 0) {
4327 cpuhp_remove_multi_state(lttng_hp_prepare);
4328 lttng_hp_prepare = 0;
4329 return ret;
4330 }
4331 lttng_hp_online = ret;
4332 lttng_rb_set_hp_online(ret);
4333
4334 return 0;
4335}
4336
4337static void __exit lttng_exit_cpu_hotplug(void)
4338{
4339 lttng_rb_set_hp_online(0);
4340 cpuhp_remove_multi_state(lttng_hp_online);
4341 lttng_rb_set_hp_prepare(0);
4342 cpuhp_remove_multi_state(lttng_hp_prepare);
4343}
4344
4345#else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4346static int lttng_init_cpu_hotplug(void)
4347{
4348 return 0;
4349}
4350static void lttng_exit_cpu_hotplug(void)
4351{
4352}
4353#endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4354
4355static int __init lttng_events_init(void)
4356{
4357 int ret;
4358
4359 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
4360 if (ret)
4361 return ret;
4362 ret = wrapper_get_pfnblock_flags_mask_init();
4363 if (ret)
4364 return ret;
4365 ret = wrapper_get_pageblock_flags_mask_init();
4366 if (ret)
4367 return ret;
4368 ret = lttng_probes_init();
4369 if (ret)
4370 return ret;
4371 ret = lttng_context_init();
4372 if (ret)
4373 return ret;
4374 ret = lttng_tracepoint_init();
4375 if (ret)
4376 goto error_tp;
4377 event_recorder_cache = KMEM_CACHE(lttng_kernel_event_recorder, 0);
4378 if (!event_recorder_cache) {
4379 ret = -ENOMEM;
4380 goto error_kmem_event_recorder;
4381 }
4382 event_recorder_private_cache = KMEM_CACHE(lttng_kernel_event_recorder_private, 0);
4383 if (!event_recorder_private_cache) {
4384 ret = -ENOMEM;
4385 goto error_kmem_event_recorder_private;
4386 }
4387 event_notifier_cache = KMEM_CACHE(lttng_kernel_event_notifier, 0);
4388 if (!event_notifier_cache) {
4389 ret = -ENOMEM;
4390 goto error_kmem_event_notifier;
4391 }
4392 event_notifier_private_cache = KMEM_CACHE(lttng_kernel_event_notifier_private, 0);
4393 if (!event_notifier_private_cache) {
4394 ret = -ENOMEM;
4395 goto error_kmem_event_notifier_private;
4396 }
4397 ret = lttng_abi_init();
4398 if (ret)
4399 goto error_abi;
4400 ret = lttng_logger_init();
4401 if (ret)
4402 goto error_logger;
4403 ret = lttng_init_cpu_hotplug();
4404 if (ret)
4405 goto error_hotplug;
4406 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
4407 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4408 __stringify(LTTNG_MODULES_MINOR_VERSION),
4409 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4410 LTTNG_MODULES_EXTRAVERSION,
4411 LTTNG_VERSION_NAME,
4412#ifdef LTTNG_EXTRA_VERSION_GIT
4413 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4414#else
4415 "",
4416#endif
4417#ifdef LTTNG_EXTRA_VERSION_NAME
4418 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4419#else
4420 "");
4421#endif
4422#ifdef CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM
4423 printk(KERN_NOTICE "LTTng: Experimental bitwise enum enabled.\n");
4424#endif /* CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM */
4425 return 0;
4426
4427error_hotplug:
4428 lttng_logger_exit();
4429error_logger:
4430 lttng_abi_exit();
4431error_abi:
4432 kmem_cache_destroy(event_notifier_private_cache);
4433error_kmem_event_notifier_private:
4434 kmem_cache_destroy(event_notifier_cache);
4435error_kmem_event_notifier:
4436 kmem_cache_destroy(event_recorder_private_cache);
4437error_kmem_event_recorder_private:
4438 kmem_cache_destroy(event_recorder_cache);
4439error_kmem_event_recorder:
4440 lttng_tracepoint_exit();
4441error_tp:
4442 lttng_context_exit();
4443 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
4444 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4445 __stringify(LTTNG_MODULES_MINOR_VERSION),
4446 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4447 LTTNG_MODULES_EXTRAVERSION,
4448 LTTNG_VERSION_NAME,
4449#ifdef LTTNG_EXTRA_VERSION_GIT
4450 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4451#else
4452 "",
4453#endif
4454#ifdef LTTNG_EXTRA_VERSION_NAME
4455 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4456#else
4457 "");
4458#endif
4459 return ret;
4460}
4461
4462module_init(lttng_events_init);
4463
4464static void __exit lttng_events_exit(void)
4465{
4466 struct lttng_kernel_session_private *session_priv, *tmpsession_priv;
4467
4468 lttng_exit_cpu_hotplug();
4469 lttng_logger_exit();
4470 lttng_abi_exit();
4471 list_for_each_entry_safe(session_priv, tmpsession_priv, &sessions, list)
4472 lttng_session_destroy(session_priv->pub);
4473 kmem_cache_destroy(event_recorder_cache);
4474 kmem_cache_destroy(event_recorder_private_cache);
4475 kmem_cache_destroy(event_notifier_cache);
4476 kmem_cache_destroy(event_notifier_private_cache);
4477 lttng_tracepoint_exit();
4478 lttng_context_exit();
4479 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
4480 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4481 __stringify(LTTNG_MODULES_MINOR_VERSION),
4482 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4483 LTTNG_MODULES_EXTRAVERSION,
4484 LTTNG_VERSION_NAME,
4485#ifdef LTTNG_EXTRA_VERSION_GIT
4486 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4487#else
4488 "",
4489#endif
4490#ifdef LTTNG_EXTRA_VERSION_NAME
4491 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4492#else
4493 "");
4494#endif
4495}
4496
4497module_exit(lttng_events_exit);
4498
4499#include <generated/patches.h>
4500#ifdef LTTNG_EXTRA_VERSION_GIT
4501MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
4502#endif
4503#ifdef LTTNG_EXTRA_VERSION_NAME
4504MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
4505#endif
4506MODULE_LICENSE("GPL and additional rights");
4507MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
4508MODULE_DESCRIPTION("LTTng tracer");
4509MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
4510 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
4511 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
4512 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
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