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Extract event enabler fields to specialized struct
[lttng-modules.git] / src / lttng-events.c
CommitLineData
b7cdc182 1/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed 2 *
a90917c3 3 * lttng-events.c
4e3c1b9b 4 *
4e3c1b9b 5 * Holds LTTng per-session event registry.
17baffe2 6 *
886d51a3 7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4e3c1b9b
MD		 8 */
9
389d7070
MD		 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
4e3c1b9b 16#include <linux/module.h>
c0e31d2e
MD		 17#include <linux/mutex.h>
18#include <linux/sched.h>
11b5a3c2 19#include <linux/slab.h>
c099397a 20#include <linux/jiffies.h>
99dc9597 21#include <linux/utsname.h>
abc0446a 22#include <linux/err.h>
7e6f9ef6
MD		 23#include <linux/seq_file.h>
24#include <linux/file.h>
25#include <linux/anon_inodes.h>
241ae9a8 26#include <wrapper/file.h>
3c997079 27#include <linux/jhash.h>
8c6e7f13 28#include <linux/uaccess.h>
a606b6e8 29#include <linux/vmalloc.h>
c88f762e 30#include <linux/dmi.h>
3c997079 31
a7008254 32#include <wrapper/uuid.h>
263b6c88 33#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
241ae9a8
MD		 34#include <wrapper/random.h>
35#include <wrapper/tracepoint.h>
36#include <wrapper/list.h>
cbc19040 37#include <wrapper/types.h>
2df37e95
MD		 38#include <lttng/kernel-version.h>
39#include <lttng/events.h>
40#include <lttng/tracer.h>
41#include <lttng/abi-old.h>
42#include <lttng/endian.h>
43#include <lttng/string-utils.h>
24591303
MD		 44#include <ringbuffer/backend.h>
45#include <ringbuffer/frontend.h>
3636085f 46#include <wrapper/time.h>
4e3c1b9b 47
d83004aa
JD		 48#define METADATA_CACHE_DEFAULT_SIZE 4096
49
4e3c1b9b 50static LIST_HEAD(sessions);
a90917c3 51static LIST_HEAD(lttng_transport_list);
d83004aa
JD		 52/*
53 * Protect the sessions and metadata caches.
54 */
4e3c1b9b
MD		 55static DEFINE_MUTEX(sessions_mutex);
56static struct kmem_cache *event_cache;
57
b2bc0bc8
FD		 58static void lttng_session_lazy_sync_event_enablers(struct lttng_session *session);
59static void lttng_session_sync_event_enablers(struct lttng_session *session);
60static void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler);
3c997079 61
a90917c3
MD		 62static void _lttng_event_destroy(struct lttng_event *event);
63static void _lttng_channel_destroy(struct lttng_channel *chan);
64static int _lttng_event_unregister(struct lttng_event *event);
c099397a 65static
a90917c3
MD		 66int _lttng_event_metadata_statedump(struct lttng_session *session,
67 struct lttng_channel *chan,
68 struct lttng_event *event);
c099397a 69static
a90917c3 70int _lttng_session_metadata_statedump(struct lttng_session *session);
d83004aa
JD		 71static
72void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
f513b2bf 73static
ceabb767
MD		 74int _lttng_type_statedump(struct lttng_session *session,
75 const struct lttng_type *type,
76 size_t nesting);
77static
f513b2bf
MD		 78int _lttng_field_statedump(struct lttng_session *session,
79 const struct lttng_event_field *field,
80 size_t nesting);
c099397a 81
c099397a 82void synchronize_trace(void)
abcca994 83{
92da05ce
MJ		 84#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,1,0))
85 synchronize_rcu();
86#else
abcca994 87 synchronize_sched();
92da05ce
MJ		 88#endif
89
b8590f40
MD		 90#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
91#ifdef CONFIG_PREEMPT_RT_FULL
92 synchronize_rcu();
93#endif
94#else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
abcca994
MD		 95#ifdef CONFIG_PREEMPT_RT
96 synchronize_rcu();
97#endif
b8590f40 98#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
abcca994
MD		 99}
100
3c997079
MD		 101void lttng_lock_sessions(void)
102{
103 mutex_lock(&sessions_mutex);
104}
105
106void lttng_unlock_sessions(void)
107{
108 mutex_unlock(&sessions_mutex);
109}
110
111/*
112 * Called with sessions lock held.
113 */
114int lttng_session_active(void)
115{
116 struct lttng_session *iter;
117
118 list_for_each_entry(iter, &sessions, list) {
119 if (iter->active)
120 return 1;
121 }
122 return 0;
123}
124
a90917c3 125struct lttng_session *lttng_session_create(void)
4e3c1b9b 126{
a90917c3 127 struct lttng_session *session;
d83004aa 128 struct lttng_metadata_cache *metadata_cache;
3c997079 129 int i;
4e3c1b9b
MD		 130
131 mutex_lock(&sessions_mutex);
48f5e0b5 132 session = lttng_kvzalloc(sizeof(struct lttng_session), GFP_KERNEL);
4e3c1b9b 133 if (!session)
d83004aa 134 goto err;
4e3c1b9b 135 INIT_LIST_HEAD(&session->chan);
f3d01b96 136 INIT_LIST_HEAD(&session->events);
a7008254 137 lttng_guid_gen(&session->uuid);
d83004aa
JD		 138
139 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
140 GFP_KERNEL);
141 if (!metadata_cache)
142 goto err_free_session;
0ca42eb7 143 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
d83004aa
JD		 144 if (!metadata_cache->data)
145 goto err_free_cache;
146 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
147 kref_init(&metadata_cache->refcount);
92d9f5e6 148 mutex_init(&metadata_cache->lock);
d83004aa
JD		 149 session->metadata_cache = metadata_cache;
150 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
a36580d5
MD		 151 memcpy(&metadata_cache->uuid, &session->uuid,
152 sizeof(metadata_cache->uuid));
3c997079
MD		 153 INIT_LIST_HEAD(&session->enablers_head);
154 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
155 INIT_HLIST_HEAD(&session->events_ht.table[i]);
4e3c1b9b 156 list_add(&session->list, &sessions);
d1f652f8
MD		 157 session->pid_tracker.session = session;
158 session->pid_tracker.tracker_type = TRACKER_PID;
159 session->vpid_tracker.session = session;
160 session->vpid_tracker.tracker_type = TRACKER_VPID;
161 session->uid_tracker.session = session;
162 session->uid_tracker.tracker_type = TRACKER_UID;
163 session->vuid_tracker.session = session;
164 session->vuid_tracker.tracker_type = TRACKER_VUID;
165 session->gid_tracker.session = session;
166 session->gid_tracker.tracker_type = TRACKER_GID;
167 session->vgid_tracker.session = session;
168 session->vgid_tracker.tracker_type = TRACKER_VGID;
4e3c1b9b
MD		 169 mutex_unlock(&sessions_mutex);
170 return session;
d83004aa
JD		 171
172err_free_cache:
173 kfree(metadata_cache);
174err_free_session:
48f5e0b5 175 lttng_kvfree(session);
d83004aa
JD		 176err:
177 mutex_unlock(&sessions_mutex);
178 return NULL;
179}
180
181void metadata_cache_destroy(struct kref *kref)
182{
183 struct lttng_metadata_cache *cache =
184 container_of(kref, struct lttng_metadata_cache, refcount);
a606b6e8 185 vfree(cache->data);
d83004aa 186 kfree(cache);
4e3c1b9b
MD		 187}
188
a90917c3 189void lttng_session_destroy(struct lttng_session *session)
4e3c1b9b 190{
a90917c3
MD		 191 struct lttng_channel *chan, *tmpchan;
192 struct lttng_event *event, *tmpevent;
d83004aa 193 struct lttng_metadata_stream *metadata_stream;
b2bc0bc8 194 struct lttng_event_enabler *event_enabler, *tmp_event_enabler;
dda6a249 195 int ret;
4e3c1b9b
MD		 196
197 mutex_lock(&sessions_mutex);
a8f2d0c7 198 WRITE_ONCE(session->active, 0);
1ec65de1
MD		 199 list_for_each_entry(chan, &session->chan, list) {
200 ret = lttng_syscalls_unregister(chan);
201 WARN_ON(ret);
202 }
dda6a249 203 list_for_each_entry(event, &session->events, list) {
a90917c3 204 ret = _lttng_event_unregister(event);
dda6a249
MD		 205 WARN_ON(ret);
206 }
abcca994 207 synchronize_trace(); /* Wait for in-flight events to complete */
badfe9f5
MD		 208 list_for_each_entry(chan, &session->chan, list) {
209 ret = lttng_syscalls_destroy(chan);
210 WARN_ON(ret);
211 }
b2bc0bc8 212 list_for_each_entry_safe(event_enabler, tmp_event_enabler,
3c997079 213 &session->enablers_head, node)
b2bc0bc8 214 lttng_event_enabler_destroy(event_enabler);
4e3c1b9b 215 list_for_each_entry_safe(event, tmpevent, &session->events, list)
a90917c3 216 _lttng_event_destroy(event);
d83004aa
JD		 217 list_for_each_entry_safe(chan, tmpchan, &session->chan, list) {
218 BUG_ON(chan->channel_type == METADATA_CHANNEL);
a90917c3 219 _lttng_channel_destroy(chan);
d83004aa 220 }
ab036a63 221 mutex_lock(&session->metadata_cache->lock);
d83004aa
JD		 222 list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
223 _lttng_metadata_channel_hangup(metadata_stream);
ab036a63 224 mutex_unlock(&session->metadata_cache->lock);
d1f652f8
MD		 225 lttng_id_tracker_destroy(&session->pid_tracker, false);
226 lttng_id_tracker_destroy(&session->vpid_tracker, false);
227 lttng_id_tracker_destroy(&session->uid_tracker, false);
228 lttng_id_tracker_destroy(&session->vuid_tracker, false);
229 lttng_id_tracker_destroy(&session->gid_tracker, false);
230 lttng_id_tracker_destroy(&session->vgid_tracker, false);
d83004aa 231 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
4e3c1b9b
MD		 232 list_del(&session->list);
233 mutex_unlock(&sessions_mutex);
48f5e0b5 234 lttng_kvfree(session);
4e3c1b9b
MD		 235}
236
601252cf
MD		 237int lttng_session_statedump(struct lttng_session *session)
238{
239 int ret;
240
241 mutex_lock(&sessions_mutex);
242 ret = lttng_statedump_start(session);
243 mutex_unlock(&sessions_mutex);
244 return ret;
245}
246
a90917c3 247int lttng_session_enable(struct lttng_session *session)
c0e31d2e
MD		 248{
249 int ret = 0;
a90917c3 250 struct lttng_channel *chan;
c0e31d2e
MD		 251
252 mutex_lock(&sessions_mutex);
253 if (session->active) {
254 ret = -EBUSY;
255 goto end;
256 }
c099397a 257
3c997079
MD		 258 /* Set transient enabler state to "enabled" */
259 session->tstate = 1;
260
4ef81e4a 261 /* We need to sync enablers with session before activation. */
b2bc0bc8 262 lttng_session_sync_event_enablers(session);
4ef81e4a 263
c099397a
MD		 264 /*
265 * Snapshot the number of events per channel to know the type of header
266 * we need to use.
267 */
268 list_for_each_entry(chan, &session->chan, list) {
269 if (chan->header_type)
270 continue; /* don't change it if session stop/restart */
271 if (chan->free_event_id < 31)
272 chan->header_type = 1; /* compact */
273 else
274 chan->header_type = 2; /* large */
275 }
276
64af2437 277 /* Clear each stream's quiescent state. */
09b93db9
MD		 278 list_for_each_entry(chan, &session->chan, list) {
279 if (chan->channel_type != METADATA_CHANNEL)
280 lib_ring_buffer_clear_quiescent_channel(chan->chan);
281 }
64af2437 282
a8f2d0c7
MJ		 283 WRITE_ONCE(session->active, 1);
284 WRITE_ONCE(session->been_active, 1);
a90917c3 285 ret = _lttng_session_metadata_statedump(session);
c337ddc2 286 if (ret) {
a8f2d0c7 287 WRITE_ONCE(session->active, 0);
c337ddc2
MD		 288 goto end;
289 }
290 ret = lttng_statedump_start(session);
360f38ea 291 if (ret)
a8f2d0c7 292 WRITE_ONCE(session->active, 0);
c0e31d2e
MD		 293end:
294 mutex_unlock(&sessions_mutex);
11b5a3c2 295 return ret;
c0e31d2e
MD		 296}
297
a90917c3 298int lttng_session_disable(struct lttng_session *session)
c0e31d2e
MD		 299{
300 int ret = 0;
64af2437 301 struct lttng_channel *chan;
c0e31d2e
MD		 302
303 mutex_lock(&sessions_mutex);
304 if (!session->active) {
305 ret = -EBUSY;
306 goto end;
307 }
a8f2d0c7 308 WRITE_ONCE(session->active, 0);
3c997079
MD		 309
310 /* Set transient enabler state to "disabled" */
311 session->tstate = 0;
b2bc0bc8 312 lttng_session_sync_event_enablers(session);
64af2437
MD		 313
314 /* Set each stream's quiescent state. */
09b93db9
MD		 315 list_for_each_entry(chan, &session->chan, list) {
316 if (chan->channel_type != METADATA_CHANNEL)
317 lib_ring_buffer_set_quiescent_channel(chan->chan);
318 }
c0e31d2e
MD		 319end:
320 mutex_unlock(&sessions_mutex);
11b5a3c2 321 return ret;
c0e31d2e
MD		 322}
323
9616f0bf
JD		 324int lttng_session_metadata_regenerate(struct lttng_session *session)
325{
326 int ret = 0;
327 struct lttng_channel *chan;
328 struct lttng_event *event;
329 struct lttng_metadata_cache *cache = session->metadata_cache;
330 struct lttng_metadata_stream *stream;
331
332 mutex_lock(&sessions_mutex);
333 if (!session->active) {
334 ret = -EBUSY;
335 goto end;
336 }
337
338 mutex_lock(&cache->lock);
339 memset(cache->data, 0, cache->cache_alloc);
340 cache->metadata_written = 0;
341 cache->version++;
342 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) {
343 stream->metadata_out = 0;
344 stream->metadata_in = 0;
345 }
346 mutex_unlock(&cache->lock);
347
348 session->metadata_dumped = 0;
349 list_for_each_entry(chan, &session->chan, list) {
350 chan->metadata_dumped = 0;
351 }
352
353 list_for_each_entry(event, &session->events, list) {
354 event->metadata_dumped = 0;
355 }
356
357 ret = _lttng_session_metadata_statedump(session);
358
359end:
360 mutex_unlock(&sessions_mutex);
361 return ret;
362}
363
a90917c3 364int lttng_channel_enable(struct lttng_channel *channel)
e64957da 365{
3c997079 366 int ret = 0;
e64957da 367
3c997079
MD		 368 mutex_lock(&sessions_mutex);
369 if (channel->channel_type == METADATA_CHANNEL) {
370 ret = -EPERM;
371 goto end;
372 }
373 if (channel->enabled) {
374 ret = -EEXIST;
375 goto end;
376 }
377 /* Set transient enabler state to "enabled" */
378 channel->tstate = 1;
b2bc0bc8 379 lttng_session_sync_event_enablers(channel->session);
3c997079 380 /* Set atomically the state to "enabled" */
a8f2d0c7 381 WRITE_ONCE(channel->enabled, 1);
3c997079
MD		 382end:
383 mutex_unlock(&sessions_mutex);
384 return ret;
e64957da
MD		 385}
386
a90917c3 387int lttng_channel_disable(struct lttng_channel *channel)
e64957da 388{
3c997079 389 int ret = 0;
e64957da 390
3c997079
MD		 391 mutex_lock(&sessions_mutex);
392 if (channel->channel_type == METADATA_CHANNEL) {
393 ret = -EPERM;
394 goto end;
395 }
396 if (!channel->enabled) {
397 ret = -EEXIST;
398 goto end;
399 }
400 /* Set atomically the state to "disabled" */
a8f2d0c7 401 WRITE_ONCE(channel->enabled, 0);
3c997079
MD		 402 /* Set transient enabler state to "enabled" */
403 channel->tstate = 0;
b2bc0bc8 404 lttng_session_sync_event_enablers(channel->session);
3c997079
MD		 405end:
406 mutex_unlock(&sessions_mutex);
407 return ret;
e64957da
MD		 408}
409
a90917c3 410int lttng_event_enable(struct lttng_event *event)
e64957da 411{
3c997079 412 int ret = 0;
e64957da 413
3c997079
MD		 414 mutex_lock(&sessions_mutex);
415 if (event->chan->channel_type == METADATA_CHANNEL) {
416 ret = -EPERM;
417 goto end;
418 }
419 if (event->enabled) {
420 ret = -EEXIST;
421 goto end;
422 }
a0493bef
MD		 423 switch (event->instrumentation) {
424 case LTTNG_KERNEL_TRACEPOINT:
425 case LTTNG_KERNEL_SYSCALL:
426 ret = -EINVAL;
427 break;
428 case LTTNG_KERNEL_KPROBE:
149b9a9d 429 case LTTNG_KERNEL_UPROBE:
a0493bef 430 case LTTNG_KERNEL_NOOP:
a8f2d0c7 431 WRITE_ONCE(event->enabled, 1);
a0493bef
MD		 432 break;
433 case LTTNG_KERNEL_KRETPROBE:
434 ret = lttng_kretprobes_event_enable_state(event, 1);
435 break;
e884017c 436 case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
a0493bef
MD		 437 default:
438 WARN_ON_ONCE(1);
439 ret = -EINVAL;
440 }
3c997079
MD		 441end:
442 mutex_unlock(&sessions_mutex);
443 return ret;
e64957da
MD		 444}
445
a90917c3 446int lttng_event_disable(struct lttng_event *event)
e64957da 447{
3c997079 448 int ret = 0;
e64957da 449
3c997079
MD		 450 mutex_lock(&sessions_mutex);
451 if (event->chan->channel_type == METADATA_CHANNEL) {
452 ret = -EPERM;
453 goto end;
454 }
455 if (!event->enabled) {
456 ret = -EEXIST;
457 goto end;
458 }
a0493bef
MD		 459 switch (event->instrumentation) {
460 case LTTNG_KERNEL_TRACEPOINT:
461 case LTTNG_KERNEL_SYSCALL:
462 ret = -EINVAL;
463 break;
464 case LTTNG_KERNEL_KPROBE:
149b9a9d 465 case LTTNG_KERNEL_UPROBE:
a0493bef 466 case LTTNG_KERNEL_NOOP:
a8f2d0c7 467 WRITE_ONCE(event->enabled, 0);
a0493bef
MD		 468 break;
469 case LTTNG_KERNEL_KRETPROBE:
470 ret = lttng_kretprobes_event_enable_state(event, 0);
471 break;
e884017c 472 case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
a0493bef
MD		 473 default:
474 WARN_ON_ONCE(1);
475 ret = -EINVAL;
476 }
3c997079
MD		 477end:
478 mutex_unlock(&sessions_mutex);
479 return ret;
e64957da
MD		 480}
481
a90917c3 482static struct lttng_transport *lttng_transport_find(const char *name)
f3d01b96 483{
a90917c3 484 struct lttng_transport *transport;
f3d01b96 485
a90917c3 486 list_for_each_entry(transport, &lttng_transport_list, node) {
f3d01b96
MD		 487 if (!strcmp(transport->name, name))
488 return transport;
489 }
490 return NULL;
491}
492
a90917c3 493struct lttng_channel *lttng_channel_create(struct lttng_session *session,
5dbbdb43
MD		 494 const char *transport_name,
495 void *buf_addr,
4e3c1b9b
MD		 496 size_t subbuf_size, size_t num_subbuf,
497 unsigned int switch_timer_interval,
d83004aa
JD		 498 unsigned int read_timer_interval,
499 enum channel_type channel_type)
4e3c1b9b 500{
a90917c3
MD		 501 struct lttng_channel *chan;
502 struct lttng_transport *transport = NULL;
4e3c1b9b
MD		 503
504 mutex_lock(&sessions_mutex);
d83004aa 505 if (session->been_active && channel_type != METADATA_CHANNEL)
e5382b6d 506 goto active; /* Refuse to add channel to active session */
a90917c3 507 transport = lttng_transport_find(transport_name);
f3d01b96 508 if (!transport) {
5a15f70c 509 printk(KERN_WARNING "LTTng: transport %s not found\n",
f3d01b96 510 transport_name);
c0e31d2e 511 goto notransport;
f3d01b96 512 }
a33c9927 513 if (!try_module_get(transport->owner)) {
5a15f70c 514 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
a33c9927
MD		 515 goto notransport;
516 }
a90917c3 517 chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL);
4e3c1b9b 518 if (!chan)
c0e31d2e 519 goto nomem;
4e3c1b9b 520 chan->session = session;
05d32c64 521 chan->id = session->free_chan_id++;
3b731ab1 522 chan->ops = &transport->ops;
125b4df4
MD		 523 /*
524 * Note: the channel creation op already writes into the packet
525 * headers. Therefore the "chan" information used as input
526 * should be already accessible.
527 */
5f5ddf01
MD		 528 chan->chan = transport->ops.channel_create(transport_name,
529 chan, buf_addr, subbuf_size, num_subbuf,
530 switch_timer_interval, read_timer_interval);
f3d01b96
MD		 531 if (!chan->chan)
532 goto create_error;
3c997079 533 chan->tstate = 1;
e64957da 534 chan->enabled = 1;
a33c9927 535 chan->transport = transport;
d83004aa 536 chan->channel_type = channel_type;
4e3c1b9b
MD		 537 list_add(&chan->list, &session->chan);
538 mutex_unlock(&sessions_mutex);
539 return chan;
540
f3d01b96
MD		 541create_error:
542 kfree(chan);
c0e31d2e 543nomem:
a33c9927
MD		 544 if (transport)
545 module_put(transport->owner);
c0e31d2e 546notransport:
e5382b6d 547active:
4e3c1b9b
MD		 548 mutex_unlock(&sessions_mutex);
549 return NULL;
550}
551
552/*
d83004aa
JD		 553 * Only used internally at session destruction for per-cpu channels, and
554 * when metadata channel is released.
555 * Needs to be called with sessions mutex held.
4e3c1b9b 556 */
aa7c23a9 557static
a90917c3 558void _lttng_channel_destroy(struct lttng_channel *chan)
4e3c1b9b 559{
11b5a3c2 560 chan->ops->channel_destroy(chan->chan);
a33c9927 561 module_put(chan->transport->owner);
4e3c1b9b 562 list_del(&chan->list);
8070f5c0 563 lttng_destroy_context(chan->ctx);
4e3c1b9b
MD		 564 kfree(chan);
565}
566
d83004aa
JD		 567void lttng_metadata_channel_destroy(struct lttng_channel *chan)
568{
569 BUG_ON(chan->channel_type != METADATA_CHANNEL);
570
571 /* Protect the metadata cache with the sessions_mutex. */
572 mutex_lock(&sessions_mutex);
573 _lttng_channel_destroy(chan);
574 mutex_unlock(&sessions_mutex);
575}
576EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
577
578static
579void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
580{
581 stream->finalized = 1;
582 wake_up_interruptible(&stream->read_wait);
583}
584
e5382b6d
MD		 585/*
586 * Supports event creation while tracing session is active.
3c997079 587 * Needs to be called with sessions mutex held.
e5382b6d 588 */
3c997079
MD		 589struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
590 struct lttng_kernel_event *event_param,
591 void *filter,
592 const struct lttng_event_desc *event_desc,
593 enum lttng_kernel_instrumentation itype)
4e3c1b9b 594{
3c997079 595 struct lttng_session *session = chan->session;
a90917c3 596 struct lttng_event *event;
3c997079
MD		 597 const char *event_name;
598 struct hlist_head *head;
599 size_t name_len;
600 uint32_t hash;
3d084699 601 int ret;
4e3c1b9b 602
abc0446a 603 if (chan->free_event_id == -1U) {
4cf0bf51 604 ret = -EMFILE;
e5382b6d 605 goto full;
abc0446a 606 }
3c997079
MD		 607
608 switch (itype) {
609 case LTTNG_KERNEL_TRACEPOINT:
610 event_name = event_desc->name;
611 break;
612 case LTTNG_KERNEL_KPROBE:
149b9a9d 613 case LTTNG_KERNEL_UPROBE:
3c997079 614 case LTTNG_KERNEL_KRETPROBE:
3c997079 615 case LTTNG_KERNEL_NOOP:
33a39a3c 616 case LTTNG_KERNEL_SYSCALL:
3c997079
MD		 617 event_name = event_param->name;
618 break;
e884017c 619 case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
3c997079
MD		 620 default:
621 WARN_ON_ONCE(1);
622 ret = -EINVAL;
623 goto type_error;
624 }
625 name_len = strlen(event_name);
626 hash = jhash(event_name, name_len, 0);
627 head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
d216ecae 628 lttng_hlist_for_each_entry(event, head, hlist) {
3c997079
MD		 629 WARN_ON_ONCE(!event->desc);
630 if (!strncmp(event->desc->name, event_name,
631 LTTNG_KERNEL_SYM_NAME_LEN - 1)
632 && chan == event->chan) {
633 ret = -EEXIST;
634 goto exist;
abc0446a
MD		 635 }
636 }
3c997079 637
11b5a3c2 638 event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
abc0446a 639 if (!event) {
4cf0bf51 640 ret = -ENOMEM;
4e3c1b9b 641 goto cache_error;
abc0446a 642 }
4e3c1b9b
MD		 643 event->chan = chan;
644 event->filter = filter;
e5382b6d 645 event->id = chan->free_event_id++;
3c997079
MD		 646 event->instrumentation = itype;
647 event->evtype = LTTNG_TYPE_EVENT;
07dfc1d0 648 INIT_LIST_HEAD(&event->bytecode_runtime_head);
3c997079
MD		 649 INIT_LIST_HEAD(&event->enablers_ref_head);
650
651 switch (itype) {
ab2277d6 652 case LTTNG_KERNEL_TRACEPOINT:
3c997079
MD		 653 /* Event will be enabled by enabler sync. */
654 event->enabled = 0;
655 event->registered = 0;
656 event->desc = lttng_event_get(event_name);
abc0446a 657 if (!event->desc) {
4cf0bf51 658 ret = -ENOENT;
d3dbe23c 659 goto register_error;
abc0446a 660 }
3c997079
MD		 661 /* Populate lttng_event structure before event registration. */
662 smp_wmb();
baf20995 663 break;
ab2277d6 664 case LTTNG_KERNEL_KPROBE:
a0493bef
MD		 665 /*
666 * Needs to be explicitly enabled after creation, since
667 * we may want to apply filters.
668 */
669 event->enabled = 0;
3c997079
MD		 670 event->registered = 1;
671 /*
672 * Populate lttng_event structure before event
673 * registration.
674 */
675 smp_wmb();
676 ret = lttng_kprobes_register(event_name,
f17701fb
MD		 677 event_param->u.kprobe.symbol_name,
678 event_param->u.kprobe.offset,
679 event_param->u.kprobe.addr,
680 event);
abc0446a 681 if (ret) {
4cf0bf51 682 ret = -EINVAL;
d6d808f3 683 goto register_error;
abc0446a 684 }
edeb3137
MD		 685 ret = try_module_get(event->desc->owner);
686 WARN_ON_ONCE(!ret);
d6d808f3 687 break;
7371f44c
MD		 688 case LTTNG_KERNEL_KRETPROBE:
689 {
a90917c3 690 struct lttng_event *event_return;
7371f44c
MD		 691
692 /* kretprobe defines 2 events */
a0493bef
MD		 693 /*
694 * Needs to be explicitly enabled after creation, since
695 * we may want to apply filters.
696 */
697 event->enabled = 0;
3c997079 698 event->registered = 1;
7371f44c
MD		 699 event_return =
700 kmem_cache_zalloc(event_cache, GFP_KERNEL);
abc0446a 701 if (!event_return) {
4cf0bf51 702 ret = -ENOMEM;
7371f44c 703 goto register_error;
abc0446a 704 }
7371f44c
MD		 705 event_return->chan = chan;
706 event_return->filter = filter;
707 event_return->id = chan->free_event_id++;
a0493bef 708 event_return->enabled = 0;
3c997079
MD		 709 event_return->registered = 1;
710 event_return->instrumentation = itype;
7371f44c 711 /*
a90917c3 712 * Populate lttng_event structure before kretprobe registration.
7371f44c
MD		 713 */
714 smp_wmb();
3c997079 715 ret = lttng_kretprobes_register(event_name,
7371f44c
MD		 716 event_param->u.kretprobe.symbol_name,
717 event_param->u.kretprobe.offset,
718 event_param->u.kretprobe.addr,
719 event, event_return);
720 if (ret) {
721 kmem_cache_free(event_cache, event_return);
4cf0bf51 722 ret = -EINVAL;
7371f44c
MD		 723 goto register_error;
724 }
725 /* Take 2 refs on the module: one per event. */
726 ret = try_module_get(event->desc->owner);
727 WARN_ON_ONCE(!ret);
728 ret = try_module_get(event->desc->owner);
729 WARN_ON_ONCE(!ret);
a90917c3 730 ret = _lttng_event_metadata_statedump(chan->session, chan,
7371f44c 731 event_return);
abc0446a 732 WARN_ON_ONCE(ret > 0);
7371f44c
MD		 733 if (ret) {
734 kmem_cache_free(event_cache, event_return);
735 module_put(event->desc->owner);
736 module_put(event->desc->owner);
737 goto statedump_error;
738 }
739 list_add(&event_return->list, &chan->session->events);
740 break;
741 }
1ec65de1 742 case LTTNG_KERNEL_NOOP:
33a39a3c 743 case LTTNG_KERNEL_SYSCALL:
a0493bef
MD		 744 /*
745 * Needs to be explicitly enabled after creation, since
746 * we may want to apply filters.
747 */
748 event->enabled = 0;
3c997079
MD		 749 event->registered = 0;
750 event->desc = event_desc;
badfe9f5
MD		 751 switch (event_param->u.syscall.entryexit) {
752 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
753 ret = -EINVAL;
754 goto register_error;
755 case LTTNG_KERNEL_SYSCALL_ENTRY:
756 event->u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
757 break;
758 case LTTNG_KERNEL_SYSCALL_EXIT:
759 event->u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
760 break;
761 }
762 switch (event_param->u.syscall.abi) {
763 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
764 ret = -EINVAL;
765 goto register_error;
766 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE:
767 event->u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
768 break;
769 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT:
770 event->u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
771 break;
772 }
abc0446a 773 if (!event->desc) {
4cf0bf51 774 ret = -EINVAL;
259b6cb3 775 goto register_error;
abc0446a 776 }
1ec65de1 777 break;
149b9a9d 778 case LTTNG_KERNEL_UPROBE:
a344f64b
FD		 779 /*
780 * Needs to be explicitly enabled after creation, since
781 * we may want to apply filters.
782 */
783 event->enabled = 0;
784 event->registered = 1;
3aed4dca 785
a344f64b
FD		 786 /*
787 * Populate lttng_event structure before event
788 * registration.
789 */
790 smp_wmb();
149b9a9d
YB		 791
792 ret = lttng_uprobes_register(event_param->name,
56377c91 793 event_param->u.uprobe.fd,
149b9a9d
YB		 794 event);
795 if (ret)
796 goto register_error;
797 ret = try_module_get(event->desc->owner);
798 WARN_ON_ONCE(!ret);
799 break;
e884017c 800 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
baf20995
MD		 801 default:
802 WARN_ON_ONCE(1);
4cf0bf51 803 ret = -EINVAL;
df07930b 804 goto register_error;
baf20995 805 }
a90917c3 806 ret = _lttng_event_metadata_statedump(chan->session, chan, event);
abc0446a
MD		 807 WARN_ON_ONCE(ret > 0);
808 if (ret) {
c099397a 809 goto statedump_error;
abc0446a 810 }
3c997079 811 hlist_add_head(&event->hlist, head);
dda6a249 812 list_add(&event->list, &chan->session->events);
4e3c1b9b
MD		 813 return event;
814
c099397a 815statedump_error:
259b6cb3 816 /* If a statedump error occurs, events will not be readable. */
11b5a3c2 817register_error:
11b5a3c2 818 kmem_cache_free(event_cache, event);
4e3c1b9b
MD		 819cache_error:
820exist:
3c997079 821type_error:
e5382b6d 822full:
4cf0bf51 823 return ERR_PTR(ret);
4e3c1b9b
MD		 824}
825
3c997079
MD		 826struct lttng_event *lttng_event_create(struct lttng_channel *chan,
827 struct lttng_kernel_event *event_param,
828 void *filter,
829 const struct lttng_event_desc *event_desc,
830 enum lttng_kernel_instrumentation itype)
831{
832 struct lttng_event *event;
833
834 mutex_lock(&sessions_mutex);
835 event = _lttng_event_create(chan, event_param, filter, event_desc,
836 itype);
837 mutex_unlock(&sessions_mutex);
838 return event;
839}
840
841/* Only used for tracepoints for now. */
842static
843void register_event(struct lttng_event *event)
844{
845 const struct lttng_event_desc *desc;
f127e61e 846 int ret = -EINVAL;
3c997079 847
3c997079
MD		 848 if (event->registered)
849 return;
4ecb5ad5 850
3c997079 851 desc = event->desc;
4ecb5ad5
MD		 852 switch (event->instrumentation) {
853 case LTTNG_KERNEL_TRACEPOINT:
854 ret = lttng_wrapper_tracepoint_probe_register(desc->kname,
855 desc->probe_callback,
856 event);
857 break;
858 case LTTNG_KERNEL_SYSCALL:
badfe9f5 859 ret = lttng_syscall_filter_enable(event->chan, event);
4ecb5ad5
MD		 860 break;
861 case LTTNG_KERNEL_KPROBE:
a344f64b 862 case LTTNG_KERNEL_UPROBE:
4ecb5ad5 863 case LTTNG_KERNEL_KRETPROBE:
4ecb5ad5
MD		 864 case LTTNG_KERNEL_NOOP:
865 ret = 0;
866 break;
e884017c 867 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
4ecb5ad5
MD		 868 default:
869 WARN_ON_ONCE(1);
870 }
3c997079
MD		 871 if (!ret)
872 event->registered = 1;
873}
874
4e3c1b9b
MD		 875/*
876 * Only used internally at session destruction.
877 */
a90917c3 878int _lttng_event_unregister(struct lttng_event *event)
4e3c1b9b 879{
4ecb5ad5 880 const struct lttng_event_desc *desc;
11b5a3c2
MD		 881 int ret = -EINVAL;
882
3c997079
MD		 883 if (!event->registered)
884 return 0;
885
4ecb5ad5 886 desc = event->desc;
38d024ae 887 switch (event->instrumentation) {
ab2277d6 888 case LTTNG_KERNEL_TRACEPOINT:
20591cf7 889 ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname,
85a9ca7f 890 event->desc->probe_callback,
11b5a3c2 891 event);
baf20995 892 break;
ab2277d6 893 case LTTNG_KERNEL_KPROBE:
f17701fb 894 lttng_kprobes_unregister(event);
d6d808f3
MD		 895 ret = 0;
896 break;
7371f44c
MD		 897 case LTTNG_KERNEL_KRETPROBE:
898 lttng_kretprobes_unregister(event);
899 ret = 0;
900 break;
33a39a3c 901 case LTTNG_KERNEL_SYSCALL:
badfe9f5 902 ret = lttng_syscall_filter_disable(event->chan, event);
4ecb5ad5
MD		 903 break;
904 case LTTNG_KERNEL_NOOP:
259b6cb3
MD		 905 ret = 0;
906 break;
149b9a9d
YB		 907 case LTTNG_KERNEL_UPROBE:
908 lttng_uprobes_unregister(event);
909 ret = 0;
910 break;
e884017c 911 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
baf20995
MD		 912 default:
913 WARN_ON_ONCE(1);
914 }
3c997079
MD		 915 if (!ret)
916 event->registered = 0;
dda6a249
MD		 917 return ret;
918}
919
920/*
921 * Only used internally at session destruction.
922 */
be066e6c 923static
a90917c3 924void _lttng_event_destroy(struct lttng_event *event)
dda6a249 925{
edeb3137
MD		 926 switch (event->instrumentation) {
927 case LTTNG_KERNEL_TRACEPOINT:
a90917c3 928 lttng_event_put(event->desc);
edeb3137
MD		 929 break;
930 case LTTNG_KERNEL_KPROBE:
931 module_put(event->desc->owner);
932 lttng_kprobes_destroy_private(event);
933 break;
7371f44c
MD		 934 case LTTNG_KERNEL_KRETPROBE:
935 module_put(event->desc->owner);
936 lttng_kretprobes_destroy_private(event);
937 break;
259b6cb3 938 case LTTNG_KERNEL_NOOP:
33a39a3c 939 case LTTNG_KERNEL_SYSCALL:
259b6cb3 940 break;
149b9a9d
YB		 941 case LTTNG_KERNEL_UPROBE:
942 module_put(event->desc->owner);
943 lttng_uprobes_destroy_private(event);
944 break;
e884017c 945 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
edeb3137
MD		 946 default:
947 WARN_ON_ONCE(1);
948 }
dda6a249 949 list_del(&event->list);
8070f5c0 950 lttng_destroy_context(event->ctx);
11b5a3c2 951 kmem_cache_free(event_cache, event);
4e3c1b9b
MD		 952}
953
d1f652f8
MD		 954struct lttng_id_tracker *get_tracker(struct lttng_session *session,
955 enum tracker_type tracker_type)
e0130fab 956{
d1f652f8
MD		 957 switch (tracker_type) {
958 case TRACKER_PID:
959 return &session->pid_tracker;
960 case TRACKER_VPID:
961 return &session->vpid_tracker;
962 case TRACKER_UID:
963 return &session->uid_tracker;
964 case TRACKER_VUID:
965 return &session->vuid_tracker;
966 case TRACKER_GID:
967 return &session->gid_tracker;
968 case TRACKER_VGID:
969 return &session->vgid_tracker;
970 default:
971 WARN_ON_ONCE(1);
972 return NULL;
973 }
974}
975
976int lttng_session_track_id(struct lttng_session *session,
977 enum tracker_type tracker_type, int id)
978{
979 struct lttng_id_tracker *tracker;
e0130fab
MD		 980 int ret;
981
d1f652f8
MD		 982 tracker = get_tracker(session, tracker_type);
983 if (!tracker)
984 return -EINVAL;
985 if (id < -1)
e0130fab
MD		 986 return -EINVAL;
987 mutex_lock(&sessions_mutex);
d1f652f8
MD		 988 if (id == -1) {
989 /* track all ids: destroy tracker. */
990 lttng_id_tracker_destroy(tracker, true);
e0130fab
MD		 991 ret = 0;
992 } else {
d1f652f8 993 ret = lttng_id_tracker_add(tracker, id);
e0130fab 994 }
e0130fab
MD		 995 mutex_unlock(&sessions_mutex);
996 return ret;
997}
998
d1f652f8
MD		 999int lttng_session_untrack_id(struct lttng_session *session,
1000 enum tracker_type tracker_type, int id)
e0130fab 1001{
d1f652f8 1002 struct lttng_id_tracker *tracker;
e0130fab
MD		 1003 int ret;
1004
d1f652f8
MD		 1005 tracker = get_tracker(session, tracker_type);
1006 if (!tracker)
1007 return -EINVAL;
1008 if (id < -1)
e0130fab
MD		 1009 return -EINVAL;
1010 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1011 if (id == -1) {
1012 /* untrack all ids: replace by empty tracker. */
1013 ret = lttng_id_tracker_empty_set(tracker);
e0130fab 1014 } else {
d1f652f8 1015 ret = lttng_id_tracker_del(tracker, id);
e0130fab 1016 }
e0130fab
MD		 1017 mutex_unlock(&sessions_mutex);
1018 return ret;
1019}
1020
7e6f9ef6 1021static
d1f652f8 1022void *id_list_start(struct seq_file *m, loff_t *pos)
7e6f9ef6 1023{
d1f652f8
MD		 1024 struct lttng_id_tracker *id_tracker = m->private;
1025 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1026 struct lttng_id_hash_node *e;
7e6f9ef6
MD		 1027 int iter = 0, i;
1028
1029 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1030 if (id_tracker_p) {
1031 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1032 struct hlist_head *head = &id_tracker_p->id_hash[i];
7e6f9ef6 1033
f934e302 1034 lttng_hlist_for_each_entry(e, head, hlist) {
7e6f9ef6
MD		 1035 if (iter++ >= *pos)
1036 return e;
1037 }
1038 }
1039 } else {
d1f652f8 1040 /* ID tracker disabled. */
7e6f9ef6 1041 if (iter >= *pos && iter == 0) {
d1f652f8 1042 return id_tracker_p; /* empty tracker */
7e6f9ef6
MD		 1043 }
1044 iter++;
1045 }
1046 /* End of list */
1047 return NULL;
1048}
1049
1050/* Called with sessions_mutex held. */
1051static
d1f652f8 1052void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
7e6f9ef6 1053{
d1f652f8
MD		 1054 struct lttng_id_tracker *id_tracker = m->private;
1055 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1056 struct lttng_id_hash_node *e;
7e6f9ef6
MD		 1057 int iter = 0, i;
1058
1059 (*ppos)++;
d1f652f8
MD		 1060 if (id_tracker_p) {
1061 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1062 struct hlist_head *head = &id_tracker_p->id_hash[i];
7e6f9ef6 1063
f934e302 1064 lttng_hlist_for_each_entry(e, head, hlist) {
7e6f9ef6
MD		 1065 if (iter++ >= *ppos)
1066 return e;
1067 }
1068 }
1069 } else {
d1f652f8 1070 /* ID tracker disabled. */
7e6f9ef6 1071 if (iter >= *ppos && iter == 0)
d1f652f8 1072 return p; /* empty tracker */
7e6f9ef6
MD		 1073 iter++;
1074 }
1075
1076 /* End of list */
1077 return NULL;
1078}
1079
1080static
d1f652f8 1081void id_list_stop(struct seq_file *m, void *p)
7e6f9ef6
MD		 1082{
1083 mutex_unlock(&sessions_mutex);
1084}
1085
1086static
d1f652f8 1087int id_list_show(struct seq_file *m, void *p)
7e6f9ef6 1088{
d1f652f8
MD		 1089 struct lttng_id_tracker *id_tracker = m->private;
1090 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1091 int id;
7e6f9ef6 1092
d1f652f8 1093 if (p == id_tracker_p) {
7e6f9ef6 1094 /* Tracker disabled. */
d1f652f8 1095 id = -1;
7e6f9ef6 1096 } else {
d1f652f8 1097 const struct lttng_id_hash_node *e = p;
7e6f9ef6 1098
d1f652f8
MD		 1099 id = lttng_id_tracker_get_node_id(e);
1100 }
1101 switch (id_tracker->tracker_type) {
1102 case TRACKER_PID:
1103 seq_printf(m, "process { pid = %d; };\n", id);
1104 break;
1105 case TRACKER_VPID:
1106 seq_printf(m, "process { vpid = %d; };\n", id);
1107 break;
1108 case TRACKER_UID:
1109 seq_printf(m, "user { uid = %d; };\n", id);
1110 break;
1111 case TRACKER_VUID:
1112 seq_printf(m, "user { vuid = %d; };\n", id);
1113 break;
1114 case TRACKER_GID:
1115 seq_printf(m, "group { gid = %d; };\n", id);
1116 break;
1117 case TRACKER_VGID:
1118 seq_printf(m, "group { vgid = %d; };\n", id);
1119 break;
1120 default:
1121 seq_printf(m, "UNKNOWN { field = %d };\n", id);
7e6f9ef6 1122 }
7e6f9ef6
MD		 1123 return 0;
1124}
1125
1126static
d1f652f8
MD		 1127const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1128 .start = id_list_start,
1129 .next = id_list_next,
1130 .stop = id_list_stop,
1131 .show = id_list_show,
7e6f9ef6
MD		 1132};
1133
1134static
d1f652f8 1135int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
7e6f9ef6 1136{
d1f652f8 1137 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
7e6f9ef6
MD		 1138}
1139
1140static
d1f652f8 1141int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
7e6f9ef6
MD		 1142{
1143 struct seq_file *m = file->private_data;
d1f652f8 1144 struct lttng_id_tracker *id_tracker = m->private;
7e6f9ef6
MD		 1145 int ret;
1146
d1f652f8 1147 WARN_ON_ONCE(!id_tracker);
7e6f9ef6 1148 ret = seq_release(inode, file);
d1f652f8
MD		 1149 if (!ret)
1150 fput(id_tracker->session->file);
7e6f9ef6
MD		 1151 return ret;
1152}
1153
d1f652f8 1154const struct file_operations lttng_tracker_ids_list_fops = {
7e6f9ef6 1155 .owner = THIS_MODULE,
d1f652f8 1156 .open = lttng_tracker_ids_list_open,
7e6f9ef6
MD		 1157 .read = seq_read,
1158 .llseek = seq_lseek,
d1f652f8 1159 .release = lttng_tracker_ids_list_release,
7e6f9ef6
MD		 1160};
1161
d1f652f8
MD		 1162int lttng_session_list_tracker_ids(struct lttng_session *session,
1163 enum tracker_type tracker_type)
7e6f9ef6 1164{
d1f652f8 1165 struct file *tracker_ids_list_file;
7e6f9ef6
MD		 1166 struct seq_file *m;
1167 int file_fd, ret;
1168
1169 file_fd = lttng_get_unused_fd();
1170 if (file_fd < 0) {
1171 ret = file_fd;
1172 goto fd_error;
1173 }
1174
d1f652f8
MD		 1175 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1176 &lttng_tracker_ids_list_fops,
7e6f9ef6 1177 NULL, O_RDWR);
d1f652f8
MD		 1178 if (IS_ERR(tracker_ids_list_file)) {
1179 ret = PTR_ERR(tracker_ids_list_file);
7e6f9ef6
MD		 1180 goto file_error;
1181 }
98d7281c
MJ		 1182 if (!atomic_long_add_unless(&session->file->f_count, 1, LONG_MAX)) {
1183 ret = -EOVERFLOW;
9c1f4643
MD		 1184 goto refcount_error;
1185 }
d1f652f8 1186 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
7e6f9ef6
MD		 1187 if (ret < 0)
1188 goto open_error;
d1f652f8
MD		 1189 m = tracker_ids_list_file->private_data;
1190
1191 m->private = get_tracker(session, tracker_type);
1192 BUG_ON(!m->private);
1193 fd_install(file_fd, tracker_ids_list_file);
7e6f9ef6
MD		 1194
1195 return file_fd;
1196
1197open_error:
9c1f4643
MD		 1198 atomic_long_dec(&session->file->f_count);
1199refcount_error:
d1f652f8 1200 fput(tracker_ids_list_file);
7e6f9ef6
MD		 1201file_error:
1202 put_unused_fd(file_fd);
1203fd_error:
1204 return ret;
1205}
1206
3c997079
MD		 1207/*
1208 * Enabler management.
1209 */
1210static
4993071a
PP		 1211int lttng_match_enabler_star_glob(const char *desc_name,
1212 const char *pattern)
3c997079 1213{
cbc19040
MD		 1214 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1215 desc_name, LTTNG_SIZE_MAX))
3c997079
MD		 1216 return 0;
1217 return 1;
1218}
1219
1220static
4ecb5ad5
MD		 1221int lttng_match_enabler_name(const char *desc_name,
1222 const char *name)
3c997079 1223{
4ecb5ad5 1224 if (strcmp(desc_name, name))
3c997079
MD		 1225 return 0;
1226 return 1;
1227}
1228
1229static
1230int lttng_desc_match_enabler(const struct lttng_event_desc *desc,
1231 struct lttng_enabler *enabler)
1232{
4ecb5ad5 1233 const char *desc_name, *enabler_name;
badfe9f5 1234 bool compat = false, entry = false;
4ecb5ad5
MD		 1235
1236 enabler_name = enabler->event_param.name;
1237 switch (enabler->event_param.instrumentation) {
1238 case LTTNG_KERNEL_TRACEPOINT:
1239 desc_name = desc->name;
3b861b22
FD		 1240 switch (enabler->format_type) {
1241 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
badfe9f5 1242 return lttng_match_enabler_star_glob(desc_name, enabler_name);
3b861b22 1243 case LTTNG_ENABLER_FORMAT_NAME:
badfe9f5
MD		 1244 return lttng_match_enabler_name(desc_name, enabler_name);
1245 default:
1246 return -EINVAL;
1247 }
4ecb5ad5
MD		 1248 break;
1249 case LTTNG_KERNEL_SYSCALL:
1250 desc_name = desc->name;
badfe9f5 1251 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
4ecb5ad5 1252 desc_name += strlen("compat_");
badfe9f5
MD		 1253 compat = true;
1254 }
4ecb5ad5
MD		 1255 if (!strncmp(desc_name, "syscall_exit_",
1256 strlen("syscall_exit_"))) {
1257 desc_name += strlen("syscall_exit_");
1258 } else if (!strncmp(desc_name, "syscall_entry_",
1259 strlen("syscall_entry_"))) {
1260 desc_name += strlen("syscall_entry_");
badfe9f5 1261 entry = true;
4ecb5ad5
MD		 1262 } else {
1263 WARN_ON_ONCE(1);
1264 return -EINVAL;
1265 }
badfe9f5
MD		 1266 switch (enabler->event_param.u.syscall.entryexit) {
1267 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
1268 break;
1269 case LTTNG_KERNEL_SYSCALL_ENTRY:
1270 if (!entry)
1271 return 0;
1272 break;
1273 case LTTNG_KERNEL_SYSCALL_EXIT:
1274 if (entry)
1275 return 0;
1276 break;
1277 default:
1278 return -EINVAL;
1279 }
1280 switch (enabler->event_param.u.syscall.abi) {
1281 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
1282 break;
1283 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE:
1284 if (compat)
1285 return 0;
1286 break;
1287 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT:
1288 if (!compat)
1289 return 0;
1290 break;
1291 default:
1292 return -EINVAL;
1293 }
1294 switch (enabler->event_param.u.syscall.match) {
1295 case LTTNG_SYSCALL_MATCH_NAME:
3b861b22
FD		 1296 switch (enabler->format_type) {
1297 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
badfe9f5 1298 return lttng_match_enabler_star_glob(desc_name, enabler_name);
3b861b22 1299 case LTTNG_ENABLER_FORMAT_NAME:
badfe9f5
MD		 1300 return lttng_match_enabler_name(desc_name, enabler_name);
1301 default:
1302 return -EINVAL;
1303 }
1304 break;
1305 case LTTNG_SYSCALL_MATCH_NR:
1306 return -EINVAL; /* Not implemented. */
1307 default:
1308 return -EINVAL;
1309 }
4ecb5ad5
MD		 1310 break;
1311 default:
1312 WARN_ON_ONCE(1);
1313 return -EINVAL;
1314 }
3c997079
MD		 1315}
1316
1317static
b2bc0bc8
FD		 1318int lttng_event_enabler_match_event(struct lttng_event_enabler *event_enabler,
1319 struct lttng_event *event)
3c997079 1320{
b2bc0bc8
FD		 1321 struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(
1322 event_enabler);
1323
1324 if (base_enabler->event_param.instrumentation != event->instrumentation)
33a39a3c 1325 return 0;
b2bc0bc8
FD		 1326 if (lttng_desc_match_enabler(event->desc, base_enabler)
1327 && event->chan == event_enabler->chan)
3c997079
MD		 1328 return 1;
1329 else
1330 return 0;
1331}
1332
1333static
b2bc0bc8
FD		 1334struct lttng_enabler_ref *lttng_enabler_ref(
1335 struct list_head *enablers_ref_list,
3c997079
MD		 1336 struct lttng_enabler *enabler)
1337{
1338 struct lttng_enabler_ref *enabler_ref;
1339
b2bc0bc8 1340 list_for_each_entry(enabler_ref, enablers_ref_list, node) {
3c997079
MD		 1341 if (enabler_ref->ref == enabler)
1342 return enabler_ref;
1343 }
1344 return NULL;
1345}
1346
3c997079 1347static
b2bc0bc8 1348void lttng_create_tracepoint_if_missing(struct lttng_event_enabler *event_enabler)
3c997079 1349{
b2bc0bc8 1350 struct lttng_session *session = event_enabler->chan->session;
3c997079
MD		 1351 struct lttng_probe_desc *probe_desc;
1352 const struct lttng_event_desc *desc;
1353 int i;
1354 struct list_head *probe_list;
1355
1356 probe_list = lttng_get_probe_list_head();
1357 /*
1358 * For each probe event, if we find that a probe event matches
1359 * our enabler, create an associated lttng_event if not
1360 * already present.
1361 */
1362 list_for_each_entry(probe_desc, probe_list, head) {
1363 for (i = 0; i < probe_desc->nr_events; i++) {
1364 int found = 0;
1365 struct hlist_head *head;
1366 const char *event_name;
1367 size_t name_len;
1368 uint32_t hash;
1369 struct lttng_event *event;
1370
1371 desc = probe_desc->event_desc[i];
b2bc0bc8
FD		 1372 if (!lttng_desc_match_enabler(desc,
1373 lttng_event_enabler_as_enabler(event_enabler)))
3c997079
MD		 1374 continue;
1375 event_name = desc->name;
1376 name_len = strlen(event_name);
1377
1378 /*
1379 * Check if already created.
1380 */
1381 hash = jhash(event_name, name_len, 0);
1382 head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
d216ecae 1383 lttng_hlist_for_each_entry(event, head, hlist) {
3c997079 1384 if (event->desc == desc
b2bc0bc8 1385 && event->chan == event_enabler->chan)
3c997079
MD		 1386 found = 1;
1387 }
1388 if (found)
1389 continue;
1390
1391 /*
1392 * We need to create an event for this
1393 * event probe.
1394 */
b2bc0bc8 1395 event = _lttng_event_create(event_enabler->chan,
3c997079
MD		 1396 NULL, NULL, desc,
1397 LTTNG_KERNEL_TRACEPOINT);
1398 if (!event) {
5a15f70c 1399 printk(KERN_INFO "LTTng: Unable to create event %s\n",
3c997079
MD		 1400 probe_desc->event_desc[i]->name);
1401 }
1402 }
1403 }
1404}
1405
33a39a3c 1406static
b2bc0bc8 1407void lttng_create_syscall_if_missing(struct lttng_event_enabler *event_enabler)
33a39a3c
MD		 1408{
1409 int ret;
1410
b2bc0bc8 1411 ret = lttng_syscalls_register(event_enabler->chan, NULL);
33a39a3c
MD		 1412 WARN_ON_ONCE(ret);
1413}
1414
1415/*
1416 * Create struct lttng_event if it is missing and present in the list of
1417 * tracepoint probes.
1418 * Should be called with sessions mutex held.
1419 */
1420static
b2bc0bc8 1421void lttng_create_event_if_missing(struct lttng_event_enabler *event_enabler)
33a39a3c 1422{
b2bc0bc8 1423 switch (event_enabler->base.event_param.instrumentation) {
33a39a3c 1424 case LTTNG_KERNEL_TRACEPOINT:
b2bc0bc8 1425 lttng_create_tracepoint_if_missing(event_enabler);
33a39a3c
MD		 1426 break;
1427 case LTTNG_KERNEL_SYSCALL:
b2bc0bc8 1428 lttng_create_syscall_if_missing(event_enabler);
33a39a3c
MD		 1429 break;
1430 default:
1431 WARN_ON_ONCE(1);
1432 break;
1433 }
1434}
1435
3c997079 1436/*
b2bc0bc8 1437 * Create events associated with an event_enabler (if not already present),
3c997079
MD		 1438 * and add backward reference from the event to the enabler.
1439 * Should be called with sessions mutex held.
1440 */
1441static
b2bc0bc8 1442int lttng_event_enabler_ref_events(struct lttng_event_enabler *event_enabler)
3c997079 1443{
b2bc0bc8
FD		 1444 struct lttng_channel *chan = event_enabler->chan;
1445 struct lttng_session *session = event_enabler->chan->session;
1446 struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(event_enabler);
3c997079
MD		 1447 struct lttng_event *event;
1448
b2bc0bc8
FD		 1449 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_SYSCALL &&
1450 base_enabler->event_param.u.syscall.entryexit == LTTNG_KERNEL_SYSCALL_ENTRYEXIT &&
1451 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_SYSCALL_ABI_ALL &&
1452 base_enabler->event_param.u.syscall.match == LTTNG_SYSCALL_MATCH_NAME &&
1453 !strcmp(base_enabler->event_param.name, "*")) {
1454 if (base_enabler->enabled)
badfe9f5
MD		 1455 WRITE_ONCE(chan->syscall_all, 1);
1456 else
1457 WRITE_ONCE(chan->syscall_all, 0);
1458 }
1459
3c997079 1460 /* First ensure that probe events are created for this enabler. */
b2bc0bc8 1461 lttng_create_event_if_missing(event_enabler);
3c997079 1462
b2bc0bc8 1463 /* For each event matching event_enabler in session event list. */
3c997079
MD		 1464 list_for_each_entry(event, &session->events, list) {
1465 struct lttng_enabler_ref *enabler_ref;
1466
b2bc0bc8 1467 if (!lttng_event_enabler_match_event(event_enabler, event))
3c997079 1468 continue;
b2bc0bc8
FD		 1469 enabler_ref = lttng_enabler_ref(&event->enablers_ref_head,
1470 lttng_event_enabler_as_enabler(event_enabler));
3c997079
MD		 1471 if (!enabler_ref) {
1472 /*
1473 * If no backward ref, create it.
b2bc0bc8 1474 * Add backward ref from event to event_enabler.
3c997079
MD		 1475 */
1476 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
1477 if (!enabler_ref)
1478 return -ENOMEM;
b2bc0bc8 1479 enabler_ref->ref = lttng_event_enabler_as_enabler(event_enabler);
3c997079
MD		 1480 list_add(&enabler_ref->node,
1481 &event->enablers_ref_head);
1482 }
1483
f127e61e
MD		 1484 /*
1485 * Link filter bytecodes if not linked yet.
1486 */
b2bc0bc8 1487 lttng_event_enabler_link_bytecode(event, event_enabler);
f127e61e 1488
3c997079
MD		 1489 /* TODO: merge event context. */
1490 }
1491 return 0;
1492}
1493
1494/*
1495 * Called at module load: connect the probe on all enablers matching
1496 * this event.
1497 * Called with sessions lock held.
1498 */
1499int lttng_fix_pending_events(void)
1500{
1501 struct lttng_session *session;
1502
1503 list_for_each_entry(session, &sessions, list)
b2bc0bc8 1504 lttng_session_lazy_sync_event_enablers(session);
3c997079
MD		 1505 return 0;
1506}
1507
b2bc0bc8
FD		 1508struct lttng_event_enabler *lttng_event_enabler_create(
1509 enum lttng_enabler_format_type format_type,
3c997079
MD		 1510 struct lttng_kernel_event *event_param,
1511 struct lttng_channel *chan)
1512{
b2bc0bc8 1513 struct lttng_event_enabler *event_enabler;
3c997079 1514
b2bc0bc8
FD		 1515 event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL);
1516 if (!event_enabler)
3c997079 1517 return NULL;
b2bc0bc8
FD		 1518 event_enabler->base.format_type = format_type;
1519 INIT_LIST_HEAD(&event_enabler->base.filter_bytecode_head);
1520 memcpy(&event_enabler->base.event_param, event_param,
1521 sizeof(event_enabler->base.event_param));
1522 event_enabler->chan = chan;
3c997079 1523 /* ctx left NULL */
b2bc0bc8
FD		 1524 event_enabler->base.enabled = 0;
1525 event_enabler->base.evtype = LTTNG_TYPE_ENABLER;
3c997079 1526 mutex_lock(&sessions_mutex);
b2bc0bc8
FD		 1527 list_add(&event_enabler->node, &event_enabler->chan->session->enablers_head);
1528 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
3c997079 1529 mutex_unlock(&sessions_mutex);
b2bc0bc8 1530 return event_enabler;
3c997079
MD		 1531}
1532
b2bc0bc8 1533int lttng_event_enabler_enable(struct lttng_event_enabler *event_enabler)
3c997079
MD		 1534{
1535 mutex_lock(&sessions_mutex);
b2bc0bc8
FD		 1536 lttng_event_enabler_as_enabler(event_enabler)->enabled = 1;
1537 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
3c997079
MD		 1538 mutex_unlock(&sessions_mutex);
1539 return 0;
1540}
1541
b2bc0bc8 1542int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler)
3c997079
MD		 1543{
1544 mutex_lock(&sessions_mutex);
b2bc0bc8
FD		 1545 lttng_event_enabler_as_enabler(event_enabler)->enabled = 0;
1546 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
3c997079
MD		 1547 mutex_unlock(&sessions_mutex);
1548 return 0;
1549}
1550
b2bc0bc8 1551static
07dfc1d0
MD		 1552int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
1553 struct lttng_kernel_filter_bytecode __user *bytecode)
1554{
1555 struct lttng_filter_bytecode_node *bytecode_node;
1556 uint32_t bytecode_len;
1557 int ret;
1558
1559 ret = get_user(bytecode_len, &bytecode->len);
1560 if (ret)
1561 return ret;
1562 bytecode_node = kzalloc(sizeof(*bytecode_node) + bytecode_len,
1563 GFP_KERNEL);
1564 if (!bytecode_node)
1565 return -ENOMEM;
1566 ret = copy_from_user(&bytecode_node->bc, bytecode,
1567 sizeof(*bytecode) + bytecode_len);
1568 if (ret)
1569 goto error_free;
b2bc0bc8 1570
07dfc1d0
MD		 1571 bytecode_node->enabler = enabler;
1572 /* Enforce length based on allocated size */
1573 bytecode_node->bc.len = bytecode_len;
1574 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
b2bc0bc8 1575
07dfc1d0
MD		 1576 return 0;
1577
1578error_free:
1579 kfree(bytecode_node);
1580 return ret;
1581}
1582
b2bc0bc8
FD		 1583int lttng_event_enabler_attach_bytecode(struct lttng_event_enabler *event_enabler,
1584 struct lttng_kernel_filter_bytecode __user *bytecode)
1585{
1586 int ret;
1587 ret = lttng_enabler_attach_bytecode(
1588 lttng_event_enabler_as_enabler(event_enabler), bytecode);
1589 if (ret)
1590 goto error;
1591
1592 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
1593 return 0;
1594
1595error:
1596 return ret;
1597}
1598
3aed4dca
FD		 1599int lttng_event_add_callsite(struct lttng_event *event,
1600 struct lttng_kernel_event_callsite __user *callsite)
1601{
1602
1603 switch (event->instrumentation) {
1604 case LTTNG_KERNEL_UPROBE:
1605 return lttng_uprobes_add_callsite(event, callsite);
1606 default:
1607 return -EINVAL;
1608 }
1609}
1610
b2bc0bc8 1611int lttng_event_enabler_attach_context(struct lttng_event_enabler *event_enabler,
3c997079
MD		 1612 struct lttng_kernel_context *context_param)
1613{
1614 return -ENOSYS;
1615}
1616
1617static
1618void lttng_enabler_destroy(struct lttng_enabler *enabler)
1619{
07dfc1d0
MD		 1620 struct lttng_filter_bytecode_node *filter_node, *tmp_filter_node;
1621
1622 /* Destroy filter bytecode */
1623 list_for_each_entry_safe(filter_node, tmp_filter_node,
1624 &enabler->filter_bytecode_head, node) {
1625 kfree(filter_node);
1626 }
b2bc0bc8
FD		 1627}
1628
1629static
1630void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler)
1631{
1632 lttng_enabler_destroy(lttng_event_enabler_as_enabler(event_enabler));
07dfc1d0 1633
3c997079 1634 /* Destroy contexts */
b2bc0bc8 1635 lttng_destroy_context(event_enabler->ctx);
3c997079 1636
b2bc0bc8
FD		 1637 list_del(&event_enabler->node);
1638 kfree(event_enabler);
3c997079
MD		 1639}
1640
1641/*
b2bc0bc8 1642 * lttng_session_sync_event_enablers should be called just before starting a
3c997079
MD		 1643 * session.
1644 * Should be called with sessions mutex held.
1645 */
1646static
b2bc0bc8 1647void lttng_session_sync_event_enablers(struct lttng_session *session)
3c997079 1648{
b2bc0bc8 1649 struct lttng_event_enabler *event_enabler;
3c997079
MD		 1650 struct lttng_event *event;
1651
b2bc0bc8
FD		 1652 list_for_each_entry(event_enabler, &session->enablers_head, node)
1653 lttng_event_enabler_ref_events(event_enabler);
3c997079
MD		 1654 /*
1655 * For each event, if at least one of its enablers is enabled,
1656 * and its channel and session transient states are enabled, we
1657 * enable the event, else we disable it.
1658 */
1659 list_for_each_entry(event, &session->events, list) {
1660 struct lttng_enabler_ref *enabler_ref;
07dfc1d0
MD		 1661 struct lttng_bytecode_runtime *runtime;
1662 int enabled = 0, has_enablers_without_bytecode = 0;
3c997079 1663
4ecb5ad5
MD		 1664 switch (event->instrumentation) {
1665 case LTTNG_KERNEL_TRACEPOINT:
1666 case LTTNG_KERNEL_SYSCALL:
3c997079
MD		 1667 /* Enable events */
1668 list_for_each_entry(enabler_ref,
1669 &event->enablers_ref_head, node) {
1670 if (enabler_ref->ref->enabled) {
1671 enabled = 1;
1672 break;
1673 }
1674 }
4ecb5ad5
MD		 1675 break;
1676 default:
3c997079
MD		 1677 /* Not handled with lazy sync. */
1678 continue;
1679 }
1680 /*
1681 * Enabled state is based on union of enablers, with
1682 * intesection of session and channel transient enable
1683 * states.
1684 */
1685 enabled = enabled && session->tstate && event->chan->tstate;
1686
a8f2d0c7 1687 WRITE_ONCE(event->enabled, enabled);
3c997079
MD		 1688 /*
1689 * Sync tracepoint registration with event enabled
1690 * state.
1691 */
1692 if (enabled) {
1693 register_event(event);
1694 } else {
1695 _lttng_event_unregister(event);
1696 }
07dfc1d0
MD		 1697
1698 /* Check if has enablers without bytecode enabled */
1699 list_for_each_entry(enabler_ref,
1700 &event->enablers_ref_head, node) {
1701 if (enabler_ref->ref->enabled
1702 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
1703 has_enablers_without_bytecode = 1;
1704 break;
1705 }
1706 }
1707 event->has_enablers_without_bytecode =
1708 has_enablers_without_bytecode;
1709
1710 /* Enable filters */
1711 list_for_each_entry(runtime,
f127e61e 1712 &event->bytecode_runtime_head, node)
07dfc1d0 1713 lttng_filter_sync_state(runtime);
3c997079
MD		 1714 }
1715}
1716
1717/*
1718 * Apply enablers to session events, adding events to session if need
1719 * be. It is required after each modification applied to an active
1720 * session, and right before session "start".
1721 * "lazy" sync means we only sync if required.
1722 * Should be called with sessions mutex held.
1723 */
1724static
b2bc0bc8 1725void lttng_session_lazy_sync_event_enablers(struct lttng_session *session)
3c997079
MD		 1726{
1727 /* We can skip if session is not active */
1728 if (!session->active)
1729 return;
b2bc0bc8 1730 lttng_session_sync_event_enablers(session);
3c997079
MD		 1731}
1732
1ec3f75a 1733/*
d83004aa
JD		 1734 * Serialize at most one packet worth of metadata into a metadata
1735 * channel.
92d9f5e6
MD		 1736 * We grab the metadata cache mutex to get exclusive access to our metadata
1737 * buffer and to the metadata cache. Exclusive access to the metadata buffer
1738 * allows us to do racy operations such as looking for remaining space left in
1739 * packet and write, since mutual exclusion protects us from concurrent writes.
1740 * Mutual exclusion on the metadata cache allow us to read the cache content
1741 * without racing against reallocation of the cache by updates.
35097f36
JD		 1742 * Returns the number of bytes written in the channel, 0 if no data
1743 * was written and a negative value on error.
1ec3f75a 1744 */
b3b8072b 1745int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
8b97fd42 1746 struct channel *chan, bool *coherent)
d83004aa
JD		 1747{
1748 struct lib_ring_buffer_ctx ctx;
1749 int ret = 0;
1750 size_t len, reserve_len;
1751
f613e3e6 1752 /*
92d9f5e6
MD		 1753 * Ensure we support mutiple get_next / put sequences followed by
1754 * put_next. The metadata cache lock protects reading the metadata
1755 * cache. It can indeed be read concurrently by "get_next_subbuf" and
1756 * "flush" operations on the buffer invoked by different processes.
1757 * Moreover, since the metadata cache memory can be reallocated, we
1758 * need to have exclusive access against updates even though we only
1759 * read it.
f613e3e6 1760 */
92d9f5e6 1761 mutex_lock(&stream->metadata_cache->lock);
f613e3e6
MD		 1762 WARN_ON(stream->metadata_in < stream->metadata_out);
1763 if (stream->metadata_in != stream->metadata_out)
de23d59d 1764 goto end;
f613e3e6 1765
9616f0bf
JD		 1766 /* Metadata regenerated, change the version. */
1767 if (stream->metadata_cache->version != stream->version)
1768 stream->version = stream->metadata_cache->version;
1769
d83004aa 1770 len = stream->metadata_cache->metadata_written -
f613e3e6 1771 stream->metadata_in;
9de2c215 1772 if (!len)
de23d59d 1773 goto end;
d83004aa 1774 reserve_len = min_t(size_t,
b3b8072b 1775 stream->transport->ops.packet_avail_size(chan),
d83004aa 1776 len);
b3b8072b 1777 lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len,
d83004aa
JD		 1778 sizeof(char), -1);
1779 /*
1780 * If reservation failed, return an error to the caller.
1781 */
b3b8072b 1782 ret = stream->transport->ops.event_reserve(&ctx, 0);
d83004aa
JD		 1783 if (ret != 0) {
1784 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
8b97fd42 1785 stream->coherent = false;
d83004aa
JD		 1786 goto end;
1787 }
b3b8072b 1788 stream->transport->ops.event_write(&ctx,
f613e3e6 1789 stream->metadata_cache->data + stream->metadata_in,
d83004aa 1790 reserve_len);
b3b8072b 1791 stream->transport->ops.event_commit(&ctx);
f613e3e6 1792 stream->metadata_in += reserve_len;
3e75e2a7 1793 if (reserve_len < len)
8b97fd42
MD		 1794 stream->coherent = false;
1795 else
1796 stream->coherent = true;
d83004aa
JD		 1797 ret = reserve_len;
1798
1799end:
8b97fd42
MD		 1800 if (coherent)
1801 *coherent = stream->coherent;
92d9f5e6 1802 mutex_unlock(&stream->metadata_cache->lock);
d83004aa
JD		 1803 return ret;
1804}
1805
8b97fd42
MD		 1806static
1807void lttng_metadata_begin(struct lttng_session *session)
1808{
3e75e2a7
MD		 1809 if (atomic_inc_return(&session->metadata_cache->producing) == 1)
1810 mutex_lock(&session->metadata_cache->lock);
8b97fd42
MD		 1811}
1812
1813static
1814void lttng_metadata_end(struct lttng_session *session)
1815{
3e75e2a7
MD		 1816 WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
1817 if (atomic_dec_return(&session->metadata_cache->producing) == 0) {
1818 struct lttng_metadata_stream *stream;
1819
3e75e2a7
MD		 1820 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
1821 wake_up_interruptible(&stream->read_wait);
92143b2c 1822 mutex_unlock(&session->metadata_cache->lock);
3e75e2a7 1823 }
8b97fd42
MD		 1824}
1825
d83004aa
JD		 1826/*
1827 * Write the metadata to the metadata cache.
1828 * Must be called with sessions_mutex held.
92d9f5e6
MD		 1829 * The metadata cache lock protects us from concurrent read access from
1830 * thread outputting metadata content to ring buffer.
8b97fd42
MD		 1831 * The content of the printf is printed as a single atomic metadata
1832 * transaction.
d83004aa 1833 */
a90917c3 1834int lttng_metadata_printf(struct lttng_session *session,
c099397a
MD		 1835 const char *fmt, ...)
1836{
c099397a 1837 char *str;
d83004aa 1838 size_t len;
c099397a
MD		 1839 va_list ap;
1840
585e5dcc 1841 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
c099397a
MD		 1842
1843 va_start(ap, fmt);
1844 str = kvasprintf(GFP_KERNEL, fmt, ap);
1845 va_end(ap);
1846 if (!str)
1847 return -ENOMEM;
1848
1ec3f75a 1849 len = strlen(str);
3e75e2a7 1850 WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
d83004aa
JD		 1851 if (session->metadata_cache->metadata_written + len >
1852 session->metadata_cache->cache_alloc) {
1853 char *tmp_cache_realloc;
1854 unsigned int tmp_cache_alloc_size;
1855
1856 tmp_cache_alloc_size = max_t(unsigned int,
1857 session->metadata_cache->cache_alloc + len,
1858 session->metadata_cache->cache_alloc << 1);
0ca42eb7 1859 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
d83004aa
JD		 1860 if (!tmp_cache_realloc)
1861 goto err;
a606b6e8
ML		 1862 if (session->metadata_cache->data) {
1863 memcpy(tmp_cache_realloc,
1864 session->metadata_cache->data,
1865 session->metadata_cache->cache_alloc);
1866 vfree(session->metadata_cache->data);
1867 }
1868
d83004aa
JD		 1869 session->metadata_cache->cache_alloc = tmp_cache_alloc_size;
1870 session->metadata_cache->data = tmp_cache_realloc;
c099397a 1871 }
d83004aa
JD		 1872 memcpy(session->metadata_cache->data +
1873 session->metadata_cache->metadata_written,
1874 str, len);
1875 session->metadata_cache->metadata_written += len;
c099397a 1876 kfree(str);
d83004aa 1877
d83004aa
JD		 1878 return 0;
1879
1880err:
1881 kfree(str);
1882 return -ENOMEM;
c099397a
MD		 1883}
1884
f513b2bf
MD		 1885static
1886int print_tabs(struct lttng_session *session, size_t nesting)
1887{
1888 size_t i;
1889
1890 for (i = 0; i < nesting; i++) {
1891 int ret;
1892
1893 ret = lttng_metadata_printf(session, " ");
1894 if (ret) {
1895 return ret;
1896 }
1897 }
1898 return 0;
1899}
1900
ceabb767
MD		 1901static
1902int lttng_field_name_statedump(struct lttng_session *session,
1903 const struct lttng_event_field *field,
1904 size_t nesting)
1905{
1906 return lttng_metadata_printf(session, " _%s;\n", field->name);
1907}
1908
1909static
1910int _lttng_integer_type_statedump(struct lttng_session *session,
1911 const struct lttng_type *type,
1912 size_t nesting)
1913{
1914 int ret;
1915
1916 WARN_ON_ONCE(type->atype != atype_integer);
1917 ret = print_tabs(session, nesting);
1918 if (ret)
1919 return ret;
1920 ret = lttng_metadata_printf(session,
1921 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s }",
1922 type->u.integer.size,
1923 type->u.integer.alignment,
1924 type->u.integer.signedness,
1925 (type->u.integer.encoding == lttng_encode_none)
1926 ? "none"
1927 : (type->u.integer.encoding == lttng_encode_UTF8)
1928 ? "UTF8"
1929 : "ASCII",
1930 type->u.integer.base,
1931#if __BYTE_ORDER == __BIG_ENDIAN
1932 type->u.integer.reverse_byte_order ? " byte_order = le;" : ""
1933#else
1934 type->u.integer.reverse_byte_order ? " byte_order = be;" : ""
1935#endif
1936 );
1937 return ret;
1938}
1939
f513b2bf
MD		 1940/*
1941 * Must be called with sessions_mutex held.
1942 */
1943static
1944int _lttng_struct_type_statedump(struct lttng_session *session,
1945 const struct lttng_type *type,
1946 size_t nesting)
1947{
1948 int ret;
1949 uint32_t i, nr_fields;
ceabb767
MD		 1950 unsigned int alignment;
1951
1952 WARN_ON_ONCE(type->atype != atype_struct_nestable);
f513b2bf
MD		 1953
1954 ret = print_tabs(session, nesting);
1955 if (ret)
1956 return ret;
1957 ret = lttng_metadata_printf(session,
1958 "struct {\n");
1959 if (ret)
1960 return ret;
ceabb767 1961 nr_fields = type->u.struct_nestable.nr_fields;
f513b2bf
MD		 1962 for (i = 0; i < nr_fields; i++) {
1963 const struct lttng_event_field *iter_field;
1964
ceabb767 1965 iter_field = &type->u.struct_nestable.fields[i];
f513b2bf
MD		 1966 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
1967 if (ret)
1968 return ret;
1969 }
1970 ret = print_tabs(session, nesting);
1971 if (ret)
1972 return ret;
ceabb767
MD		 1973 alignment = type->u.struct_nestable.alignment;
1974 if (alignment) {
1975 ret = lttng_metadata_printf(session,
1976 "} align(%u)",
1977 alignment);
1978 } else {
1979 ret = lttng_metadata_printf(session,
1980 "}");
1981 }
f513b2bf
MD		 1982 return ret;
1983}
1984
1985/*
1986 * Must be called with sessions_mutex held.
1987 */
1988static
ceabb767 1989int _lttng_struct_field_statedump(struct lttng_session *session,
f513b2bf
MD		 1990 const struct lttng_event_field *field,
1991 size_t nesting)
1992{
1993 int ret;
1994
1995 ret = _lttng_struct_type_statedump(session,
1996 &field->type, nesting);
1997 if (ret)
1998 return ret;
ceabb767 1999 return lttng_field_name_statedump(session, field, nesting);
f513b2bf
MD		 2000}
2001
65c85aa6
MD		 2002/*
2003 * Must be called with sessions_mutex held.
2004 */
2005static
2006int _lttng_variant_type_statedump(struct lttng_session *session,
2007 const struct lttng_type *type,
2008 size_t nesting)
2009{
2010 int ret;
2011 uint32_t i, nr_choices;
2012
ceabb767
MD		 2013 WARN_ON_ONCE(type->atype != atype_variant_nestable);
2014 /*
2015 * CTF 1.8 does not allow expressing nonzero variant alignment in a nestable way.
2016 */
2017 if (type->u.variant_nestable.alignment != 0)
2018 return -EINVAL;
65c85aa6
MD		 2019 ret = print_tabs(session, nesting);
2020 if (ret)
2021 return ret;
2022 ret = lttng_metadata_printf(session,
2023 "variant <_%s> {\n",
ceabb767 2024 type->u.variant_nestable.tag_name);
65c85aa6
MD		 2025 if (ret)
2026 return ret;
ceabb767 2027 nr_choices = type->u.variant_nestable.nr_choices;
65c85aa6
MD		 2028 for (i = 0; i < nr_choices; i++) {
2029 const struct lttng_event_field *iter_field;
2030
ceabb767 2031 iter_field = &type->u.variant_nestable.choices[i];
65c85aa6
MD		 2032 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
2033 if (ret)
2034 return ret;
2035 }
2036 ret = print_tabs(session, nesting);
2037 if (ret)
2038 return ret;
2039 ret = lttng_metadata_printf(session,
2040 "}");
2041 return ret;
2042}
2043
2044/*
2045 * Must be called with sessions_mutex held.
2046 */
2047static
ceabb767 2048int _lttng_variant_field_statedump(struct lttng_session *session,
65c85aa6
MD		 2049 const struct lttng_event_field *field,
2050 size_t nesting)
2051{
2052 int ret;
2053
2054 ret = _lttng_variant_type_statedump(session,
2055 &field->type, nesting);
2056 if (ret)
2057 return ret;
ceabb767 2058 return lttng_field_name_statedump(session, field, nesting);
65c85aa6
MD		 2059}
2060
f513b2bf
MD		 2061/*
2062 * Must be called with sessions_mutex held.
2063 */
2064static
ceabb767 2065int _lttng_array_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2066 const struct lttng_event_field *field,
2067 size_t nesting)
2068{
2069 int ret;
2070 const struct lttng_type *elem_type;
2071
ceabb767
MD		 2072 WARN_ON_ONCE(field->type.atype != atype_array_nestable);
2073
2074 if (field->type.u.array_nestable.alignment) {
2075 ret = print_tabs(session, nesting);
f513b2bf
MD		 2076 if (ret)
2077 return ret;
ceabb767
MD		 2078 ret = lttng_metadata_printf(session,
2079 "struct { } align(%u) _%s_padding;\n",
2080 field->type.u.array_nestable.alignment * CHAR_BIT,
2081 field->name);
2082 if (ret)
2083 return ret;
2084 }
2085 /*
2086 * Nested compound types: Only array of structures and variants are
2087 * currently supported.
2088 */
2089 elem_type = field->type.u.array_nestable.elem_type;
2090 switch (elem_type->atype) {
2091 case atype_integer:
2092 case atype_struct_nestable:
2093 case atype_variant_nestable:
2094 ret = _lttng_type_statedump(session, elem_type, nesting);
65c85aa6
MD		 2095 if (ret)
2096 return ret;
2097 break;
ceabb767 2098
f513b2bf
MD		 2099 default:
2100 return -EINVAL;
2101 }
2102 ret = lttng_metadata_printf(session,
2103 " _%s[%u];\n",
2104 field->name,
ceabb767 2105 field->type.u.array_nestable.length);
f513b2bf
MD		 2106 return ret;
2107}
2108
2109/*
2110 * Must be called with sessions_mutex held.
2111 */
2112static
ceabb767 2113int _lttng_sequence_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2114 const struct lttng_event_field *field,
2115 size_t nesting)
2116{
2117 int ret;
2118 const char *length_name;
2119 const struct lttng_type *elem_type;
2120
ceabb767 2121 WARN_ON_ONCE(field->type.atype != atype_sequence_nestable);
f513b2bf 2122
ceabb767
MD		 2123 length_name = field->type.u.sequence_nestable.length_name;
2124
2125 if (field->type.u.sequence_nestable.alignment) {
2126 ret = print_tabs(session, nesting);
f513b2bf
MD		 2127 if (ret)
2128 return ret;
ceabb767
MD		 2129 ret = lttng_metadata_printf(session,
2130 "struct { } align(%u) _%s_padding;\n",
2131 field->type.u.sequence_nestable.alignment * CHAR_BIT,
2132 field->name);
2133 if (ret)
2134 return ret;
2135 }
2136
2137 /*
2138 * Nested compound types: Only array of structures and variants are
2139 * currently supported.
2140 */
2141 elem_type = field->type.u.sequence_nestable.elem_type;
2142 switch (elem_type->atype) {
2143 case atype_integer:
2144 case atype_struct_nestable:
2145 case atype_variant_nestable:
2146 ret = _lttng_type_statedump(session, elem_type, nesting);
65c85aa6
MD		 2147 if (ret)
2148 return ret;
2149 break;
ceabb767 2150
f513b2bf
MD		 2151 default:
2152 return -EINVAL;
2153 }
2154 ret = lttng_metadata_printf(session,
2155 " _%s[ _%s ];\n",
2156 field->name,
ceabb767 2157 field->type.u.sequence_nestable.length_name);
f513b2bf
MD		 2158 return ret;
2159}
2160
141ddf28
MD		 2161/*
2162 * Must be called with sessions_mutex held.
2163 */
2164static
ceabb767
MD		 2165int _lttng_enum_type_statedump(struct lttng_session *session,
2166 const struct lttng_type *type,
141ddf28
MD		 2167 size_t nesting)
2168{
2169 const struct lttng_enum_desc *enum_desc;
ceabb767 2170 const struct lttng_type *container_type;
141ddf28
MD		 2171 int ret;
2172 unsigned int i, nr_entries;
2173
ceabb767
MD		 2174 container_type = type->u.enum_nestable.container_type;
2175 if (container_type->atype != atype_integer) {
2176 ret = -EINVAL;
2177 goto end;
2178 }
2179 enum_desc = type->u.enum_nestable.desc;
141ddf28
MD		 2180 nr_entries = enum_desc->nr_entries;
2181
2182 ret = print_tabs(session, nesting);
2183 if (ret)
2184 goto end;
ceabb767
MD		 2185 ret = lttng_metadata_printf(session, "enum : ");
2186 if (ret)
2187 goto end;
2188 ret = _lttng_integer_type_statedump(session, container_type, 0);
141ddf28 2189 if (ret)
ceabb767
MD		 2190 goto end;
2191 ret = lttng_metadata_printf(session, " {\n");
2192 if (ret)
2193 goto end;
141ddf28
MD		 2194 /* Dump all entries */
2195 for (i = 0; i < nr_entries; i++) {
2196 const struct lttng_enum_entry *entry = &enum_desc->entries[i];
2197 int j, len;
2198
2199 ret = print_tabs(session, nesting + 1);
2200 if (ret)
2201 goto end;
2202 ret = lttng_metadata_printf(session,
2203 "\"");
2204 if (ret)
2205 goto end;
2206 len = strlen(entry->string);
2207 /* Escape the character '"' */
2208 for (j = 0; j < len; j++) {
2209 char c = entry->string[j];
2210
2211 switch (c) {
2212 case '"':
2213 ret = lttng_metadata_printf(session,
2214 "\\\"");
2215 break;
2216 case '\\':
2217 ret = lttng_metadata_printf(session,
2218 "\\\\");
2219 break;
2220 default:
2221 ret = lttng_metadata_printf(session,
2222 "%c", c);
2223 break;
2224 }
2225 if (ret)
2226 goto end;
2227 }
08ad1061
PP		 2228 ret = lttng_metadata_printf(session, "\"");
2229 if (ret)
2230 goto end;
2231
2232 if (entry->options.is_auto) {
2233 ret = lttng_metadata_printf(session, ",\n");
2234 if (ret)
2235 goto end;
141ddf28 2236 } else {
7c559490
MD		 2237 ret = lttng_metadata_printf(session,
2238 " = ");
2239 if (ret)
2240 goto end;
2241 if (entry->start.signedness)
141ddf28 2242 ret = lttng_metadata_printf(session,
7c559490
MD		 2243 "%lld", (long long) entry->start.value);
2244 else
2245 ret = lttng_metadata_printf(session,
2246 "%llu", entry->start.value);
2247 if (ret)
2248 goto end;
2249 if (entry->start.signedness == entry->end.signedness &&
2250 entry->start.value
2251 == entry->end.value) {
141ddf28 2252 ret = lttng_metadata_printf(session,
7c559490
MD		 2253 ",\n");
2254 } else {
2255 if (entry->end.signedness) {
2256 ret = lttng_metadata_printf(session,
2257 " ... %lld,\n",
2258 (long long) entry->end.value);
2259 } else {
2260 ret = lttng_metadata_printf(session,
2261 " ... %llu,\n",
2262 entry->end.value);
2263 }
141ddf28 2264 }
7c559490
MD		 2265 if (ret)
2266 goto end;
141ddf28 2267 }
141ddf28
MD		 2268 }
2269 ret = print_tabs(session, nesting);
2270 if (ret)
2271 goto end;
ceabb767 2272 ret = lttng_metadata_printf(session, "}");
141ddf28
MD		 2273end:
2274 return ret;
2275}
2276
d83004aa
JD		 2277/*
2278 * Must be called with sessions_mutex held.
2279 */
c099397a 2280static
ceabb767
MD		 2281int _lttng_enum_field_statedump(struct lttng_session *session,
2282 const struct lttng_event_field *field,
2283 size_t nesting)
2284{
2285 int ret;
2286
2287 ret = _lttng_enum_type_statedump(session, &field->type, nesting);
2288 if (ret)
2289 return ret;
2290 return lttng_field_name_statedump(session, field, nesting);
2291}
2292
2293static
2294int _lttng_integer_field_statedump(struct lttng_session *session,
2295 const struct lttng_event_field *field,
2296 size_t nesting)
2297{
2298 int ret;
2299
2300 ret = _lttng_integer_type_statedump(session, &field->type, nesting);
2301 if (ret)
2302 return ret;
2303 return lttng_field_name_statedump(session, field, nesting);
2304}
2305
2306static
2307int _lttng_string_type_statedump(struct lttng_session *session,
2308 const struct lttng_type *type,
2309 size_t nesting)
2310{
2311 int ret;
2312
2313 WARN_ON_ONCE(type->atype != atype_string);
2314 /* Default encoding is UTF8 */
2315 ret = print_tabs(session, nesting);
2316 if (ret)
2317 return ret;
2318 ret = lttng_metadata_printf(session,
2319 "string%s",
2320 type->u.string.encoding == lttng_encode_ASCII ?
2321 " { encoding = ASCII; }" : "");
2322 return ret;
2323}
2324
2325static
2326int _lttng_string_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2327 const struct lttng_event_field *field,
2328 size_t nesting)
ceabb767
MD		 2329{
2330 int ret;
2331
2332 WARN_ON_ONCE(field->type.atype != atype_string);
2333 ret = _lttng_string_type_statedump(session, &field->type, nesting);
2334 if (ret)
2335 return ret;
2336 return lttng_field_name_statedump(session, field, nesting);
2337}
2338
2339/*
2340 * Must be called with sessions_mutex held.
2341 */
2342static
2343int _lttng_type_statedump(struct lttng_session *session,
2344 const struct lttng_type *type,
2345 size_t nesting)
c099397a 2346{
c099397a 2347 int ret = 0;
c099397a 2348
ceabb767 2349 switch (type->atype) {
8070f5c0 2350 case atype_integer:
ceabb767 2351 ret = _lttng_integer_type_statedump(session, type, nesting);
8070f5c0 2352 break;
ceabb767
MD		 2353 case atype_enum_nestable:
2354 ret = _lttng_enum_type_statedump(session, type, nesting);
8070f5c0 2355 break;
ceabb767
MD		 2356 case atype_string:
2357 ret = _lttng_string_type_statedump(session, type, nesting);
2358 break;
2359 case atype_struct_nestable:
2360 ret = _lttng_struct_type_statedump(session, type, nesting);
8070f5c0 2361 break;
ceabb767
MD		 2362 case atype_variant_nestable:
2363 ret = _lttng_variant_type_statedump(session, type, nesting);
2364 break;
2365
2366 /* Nested arrays and sequences are not supported yet. */
2367 case atype_array_nestable:
2368 case atype_sequence_nestable:
2369 default:
2370 WARN_ON_ONCE(1);
2371 return -EINVAL;
8070f5c0 2372 }
ceabb767
MD		 2373 return ret;
2374}
8070f5c0 2375
ceabb767
MD		 2376/*
2377 * Must be called with sessions_mutex held.
2378 */
2379static
2380int _lttng_field_statedump(struct lttng_session *session,
2381 const struct lttng_event_field *field,
2382 size_t nesting)
2383{
2384 int ret = 0;
27d2368e 2385
ceabb767
MD		 2386 switch (field->type.atype) {
2387 case atype_integer:
2388 ret = _lttng_integer_field_statedump(session, field, nesting);
2389 break;
2390 case atype_enum_nestable:
2391 ret = _lttng_enum_field_statedump(session, field, nesting);
8070f5c0 2392 break;
8070f5c0 2393 case atype_string:
ceabb767 2394 ret = _lttng_string_field_statedump(session, field, nesting);
8070f5c0 2395 break;
ceabb767
MD		 2396 case atype_struct_nestable:
2397 ret = _lttng_struct_field_statedump(session, field, nesting);
f513b2bf 2398 break;
ceabb767
MD		 2399 case atype_array_nestable:
2400 ret = _lttng_array_field_statedump(session, field, nesting);
f513b2bf 2401 break;
ceabb767
MD		 2402 case atype_sequence_nestable:
2403 ret = _lttng_sequence_field_statedump(session, field, nesting);
f513b2bf 2404 break;
ceabb767
MD		 2405 case atype_variant_nestable:
2406 ret = _lttng_variant_field_statedump(session, field, nesting);
65c85aa6 2407 break;
f513b2bf 2408
8070f5c0
MD		 2409 default:
2410 WARN_ON_ONCE(1);
2411 return -EINVAL;
2412 }
2413 return ret;
2414}
2415
2416static
a90917c3 2417int _lttng_context_metadata_statedump(struct lttng_session *session,
8070f5c0
MD		 2418 struct lttng_ctx *ctx)
2419{
2420 int ret = 0;
2421 int i;
2422
2423 if (!ctx)
2424 return 0;
2425 for (i = 0; i < ctx->nr_fields; i++) {
2426 const struct lttng_ctx_field *field = &ctx->fields[i];
2427
f513b2bf 2428 ret = _lttng_field_statedump(session, &field->event_field, 2);
8070f5c0
MD		 2429 if (ret)
2430 return ret;
2431 }
2432 return ret;
2433}
2434
2435static
a90917c3
MD		 2436int _lttng_fields_metadata_statedump(struct lttng_session *session,
2437 struct lttng_event *event)
8070f5c0
MD		 2438{
2439 const struct lttng_event_desc *desc = event->desc;
2440 int ret = 0;
2441 int i;
2442
2443 for (i = 0; i < desc->nr_fields; i++) {
2444 const struct lttng_event_field *field = &desc->fields[i];
2445
f513b2bf 2446 ret = _lttng_field_statedump(session, field, 2);
8070f5c0
MD		 2447 if (ret)
2448 return ret;
c099397a
MD		 2449 }
2450 return ret;
2451}
2452
d83004aa
JD		 2453/*
2454 * Must be called with sessions_mutex held.
8b97fd42
MD		 2455 * The entire event metadata is printed as a single atomic metadata
2456 * transaction.
d83004aa 2457 */
c099397a 2458static
a90917c3
MD		 2459int _lttng_event_metadata_statedump(struct lttng_session *session,
2460 struct lttng_channel *chan,
2461 struct lttng_event *event)
c099397a
MD		 2462{
2463 int ret = 0;
2464
585e5dcc 2465 if (event->metadata_dumped || !LTTNG_READ_ONCE(session->active))
c099397a 2466 return 0;
d83004aa 2467 if (chan->channel_type == METADATA_CHANNEL)
c099397a
MD		 2468 return 0;
2469
8b97fd42
MD		 2470 lttng_metadata_begin(session);
2471
c099397a
MD		 2472 ret = lttng_metadata_printf(session,
2473 "event {\n"
ae734547 2474 " name = \"%s\";\n"
c099397a 2475 " id = %u;\n"
b9074a1b 2476 " stream_id = %u;\n",
c099397a
MD		 2477 event->desc->name,
2478 event->id,
2479 event->chan->id);
2480 if (ret)
2481 goto end;
2482
b9074a1b
MD		 2483 if (event->ctx) {
2484 ret = lttng_metadata_printf(session,
2485 " context := struct {\n");
2486 if (ret)
2487 goto end;
2488 }
a90917c3 2489 ret = _lttng_context_metadata_statedump(session, event->ctx);
8070f5c0
MD		 2490 if (ret)
2491 goto end;
b9074a1b
MD		 2492 if (event->ctx) {
2493 ret = lttng_metadata_printf(session,
2494 " };\n");
2495 if (ret)
2496 goto end;
2497 }
8070f5c0
MD		 2498
2499 ret = lttng_metadata_printf(session,
8070f5c0
MD		 2500 " fields := struct {\n"
2501 );
2502 if (ret)
2503 goto end;
2504
a90917c3 2505 ret = _lttng_fields_metadata_statedump(session, event);
c099397a
MD		 2506 if (ret)
2507 goto end;
2508
2509 /*
2510 * LTTng space reservation can only reserve multiples of the
2511 * byte size.
2512 */
2513 ret = lttng_metadata_printf(session,
9115fbdc
MD		 2514 " };\n"
2515 "};\n\n");
c099397a
MD		 2516 if (ret)
2517 goto end;
2518
c099397a
MD		 2519 event->metadata_dumped = 1;
2520end:
8b97fd42 2521 lttng_metadata_end(session);
c099397a
MD		 2522 return ret;
2523
2524}
2525
d83004aa
JD		 2526/*
2527 * Must be called with sessions_mutex held.
8b97fd42
MD		 2528 * The entire channel metadata is printed as a single atomic metadata
2529 * transaction.
d83004aa 2530 */
c099397a 2531static
a90917c3
MD		 2532int _lttng_channel_metadata_statedump(struct lttng_session *session,
2533 struct lttng_channel *chan)
c099397a
MD		 2534{
2535 int ret = 0;
2536
585e5dcc 2537 if (chan->metadata_dumped || !LTTNG_READ_ONCE(session->active))
c099397a 2538 return 0;
d83004aa
JD		 2539
2540 if (chan->channel_type == METADATA_CHANNEL)
c099397a
MD		 2541 return 0;
2542
8b97fd42
MD		 2543 lttng_metadata_begin(session);
2544
c099397a
MD		 2545 WARN_ON_ONCE(!chan->header_type);
2546 ret = lttng_metadata_printf(session,
2547 "stream {\n"
2548 " id = %u;\n"
9115fbdc 2549 " event.header := %s;\n"
b9074a1b 2550 " packet.context := struct packet_context;\n",
c099397a
MD		 2551 chan->id,
2552 chan->header_type == 1 ? "struct event_header_compact" :
2553 "struct event_header_large");
2554 if (ret)
2555 goto end;
2556
b9074a1b
MD		 2557 if (chan->ctx) {
2558 ret = lttng_metadata_printf(session,
2559 " event.context := struct {\n");
2560 if (ret)
2561 goto end;
2562 }
a90917c3 2563 ret = _lttng_context_metadata_statedump(session, chan->ctx);
8070f5c0
MD		 2564 if (ret)
2565 goto end;
b9074a1b
MD		 2566 if (chan->ctx) {
2567 ret = lttng_metadata_printf(session,
2568 " };\n");
2569 if (ret)
2570 goto end;
2571 }
8070f5c0
MD		 2572
2573 ret = lttng_metadata_printf(session,
b9074a1b 2574 "};\n\n");
8070f5c0 2575
c099397a
MD		 2576 chan->metadata_dumped = 1;
2577end:
8b97fd42 2578 lttng_metadata_end(session);
c099397a
MD		 2579 return ret;
2580}
2581
d83004aa
JD		 2582/*
2583 * Must be called with sessions_mutex held.
2584 */
9115fbdc 2585static
a90917c3 2586int _lttng_stream_packet_context_declare(struct lttng_session *session)
9115fbdc
MD		 2587{
2588 return lttng_metadata_printf(session,
2589 "struct packet_context {\n"
a3ccff4f
MD		 2590 " uint64_clock_monotonic_t timestamp_begin;\n"
2591 " uint64_clock_monotonic_t timestamp_end;\n"
576ca06a
MD		 2592 " uint64_t content_size;\n"
2593 " uint64_t packet_size;\n"
5b3cf4f9 2594 " uint64_t packet_seq_num;\n"
a9afe705 2595 " unsigned long events_discarded;\n"
9115fbdc 2596 " uint32_t cpu_id;\n"
c6dfdf6f 2597 "};\n\n"
9115fbdc
MD		 2598 );
2599}
2600
2601/*
2602 * Compact header:
2603 * id: range: 0 - 30.
2604 * id 31 is reserved to indicate an extended header.
2605 *
2606 * Large header:
2607 * id: range: 0 - 65534.
2608 * id 65535 is reserved to indicate an extended header.
d83004aa
JD		 2609 *
2610 * Must be called with sessions_mutex held.
9115fbdc
MD		 2611 */
2612static
a90917c3 2613int _lttng_event_header_declare(struct lttng_session *session)
9115fbdc
MD		 2614{
2615 return lttng_metadata_printf(session,
2616 "struct event_header_compact {\n"
2617 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
2618 " variant <id> {\n"
2619 " struct {\n"
a3ccff4f 2620 " uint27_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2621 " } compact;\n"
2622 " struct {\n"
2623 " uint32_t id;\n"
a3ccff4f 2624 " uint64_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2625 " } extended;\n"
2626 " } v;\n"
2627 "} align(%u);\n"
2628 "\n"
2629 "struct event_header_large {\n"
2630 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
2631 " variant <id> {\n"
2632 " struct {\n"
a3ccff4f 2633 " uint32_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2634 " } compact;\n"
2635 " struct {\n"
2636 " uint32_t id;\n"
a3ccff4f 2637 " uint64_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2638 " } extended;\n"
2639 " } v;\n"
2640 "} align(%u);\n\n",
a90917c3
MD		 2641 lttng_alignof(uint32_t) * CHAR_BIT,
2642 lttng_alignof(uint16_t) * CHAR_BIT
9115fbdc
MD		 2643 );
2644}
2645
a3ccff4f
MD		 2646 /*
2647 * Approximation of NTP time of day to clock monotonic correlation,
2648 * taken at start of trace.
2649 * Yes, this is only an approximation. Yes, we can (and will) do better
2650 * in future versions.
5283350b
MD		 2651 * This function may return a negative offset. It may happen if the
2652 * system sets the REALTIME clock to 0 after boot.
3636085f
MJ		 2653 *
2654 * Use 64bit timespec on kernels that have it, this makes 32bit arch
2655 * y2038 compliant.
a3ccff4f
MD		 2656 */
2657static
8967b2a3 2658int64_t measure_clock_offset(void)
a3ccff4f 2659{
dcb93448 2660 uint64_t monotonic_avg, monotonic[2], realtime;
2754583e 2661 uint64_t tcf = trace_clock_freq();
dcb93448 2662 int64_t offset;
a3ccff4f 2663 unsigned long flags;
3636085f
MJ		 2664#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2665 struct timespec64 rts = { 0, 0 };
2666#else
2667 struct timespec rts = { 0, 0 };
2668#endif
a3ccff4f
MD		 2669
2670 /* Disable interrupts to increase correlation precision. */
2671 local_irq_save(flags);
2672 monotonic[0] = trace_clock_read64();
3636085f
MJ		 2673#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2674 ktime_get_real_ts64(&rts);
2675#else
216b6baa 2676 getnstimeofday(&rts);
3636085f 2677#endif
a3ccff4f
MD		 2678 monotonic[1] = trace_clock_read64();
2679 local_irq_restore(flags);
2680
dcb93448 2681 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
2754583e
MD		 2682 realtime = (uint64_t) rts.tv_sec * tcf;
2683 if (tcf == NSEC_PER_SEC) {
2684 realtime += rts.tv_nsec;
2685 } else {
2686 uint64_t n = rts.tv_nsec * tcf;
2687
2688 do_div(n, NSEC_PER_SEC);
2689 realtime += n;
2690 }
dcb93448 2691 offset = (int64_t) realtime - monotonic_avg;
a3ccff4f
MD		 2692 return offset;
2693}
2694
3eb95be4
JR		 2695static
2696int print_escaped_ctf_string(struct lttng_session *session, const char *string)
2697{
0f3eaad4 2698 int ret = 0;
3eb95be4
JR		 2699 size_t i;
2700 char cur;
2701
2702 i = 0;
2703 cur = string[i];
2704 while (cur != '\0') {
2705 switch (cur) {
2706 case '\n':
2707 ret = lttng_metadata_printf(session, "%s", "\\n");
2708 break;
2709 case '\\':
2710 case '"':
2711 ret = lttng_metadata_printf(session, "%c", '\\');
2712 if (ret)
2713 goto error;
2714 /* We still print the current char */
2715 /* Fallthrough */
2716 default:
2717 ret = lttng_metadata_printf(session, "%c", cur);
2718 break;
2719 }
2720
2721 if (ret)
2722 goto error;
2723
2724 cur = string[++i];
2725 }
2726error:
2727 return ret;
2728}
2729
2730static
1c88f269
JR		 2731int print_metadata_escaped_field(struct lttng_session *session, const char *field,
2732 const char *field_value)
3eb95be4
JR		 2733{
2734 int ret;
2735
1c88f269 2736 ret = lttng_metadata_printf(session, " %s = \"", field);
3eb95be4
JR		 2737 if (ret)
2738 goto error;
2739
1c88f269 2740 ret = print_escaped_ctf_string(session, field_value);
3eb95be4
JR		 2741 if (ret)
2742 goto error;
2743
2744 ret = lttng_metadata_printf(session, "\";\n");
2745
2746error:
2747 return ret;
2748}
2749
c099397a
MD		 2750/*
2751 * Output metadata into this session's metadata buffers.
d83004aa 2752 * Must be called with sessions_mutex held.
c099397a
MD		 2753 */
2754static
a90917c3 2755int _lttng_session_metadata_statedump(struct lttng_session *session)
c099397a 2756{
30bdb6e4 2757 unsigned char *uuid_c = session->uuid.b;
a82c63f1 2758 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
c88f762e 2759 const char *product_uuid;
a90917c3
MD		 2760 struct lttng_channel *chan;
2761 struct lttng_event *event;
c099397a
MD		 2762 int ret = 0;
2763
585e5dcc 2764 if (!LTTNG_READ_ONCE(session->active))
c099397a 2765 return 0;
8b97fd42
MD		 2766
2767 lttng_metadata_begin(session);
2768
c099397a
MD		 2769 if (session->metadata_dumped)
2770 goto skip_session;
c099397a 2771
d793d5e1 2772 snprintf(uuid_s, sizeof(uuid_s),
30bdb6e4
MD		 2773 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
2774 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
2775 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
2776 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
2777 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
d793d5e1
MD		 2778
2779 ret = lttng_metadata_printf(session,
9115fbdc
MD		 2780 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
2781 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
2782 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
2783 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
a9afe705 2784 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
9115fbdc
MD		 2785 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
2786 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
d793d5e1
MD		 2787 "\n"
2788 "trace {\n"
2789 " major = %u;\n"
2790 " minor = %u;\n"
30bdb6e4 2791 " uuid = \"%s\";\n"
d793d5e1
MD		 2792 " byte_order = %s;\n"
2793 " packet.header := struct {\n"
2794 " uint32_t magic;\n"
1ec3f75a 2795 " uint8_t uuid[16];\n"
d793d5e1 2796 " uint32_t stream_id;\n"
5594698f 2797 " uint64_t stream_instance_id;\n"
0eb25f58 2798 " };\n"
d793d5e1 2799 "};\n\n",
a90917c3
MD		 2800 lttng_alignof(uint8_t) * CHAR_BIT,
2801 lttng_alignof(uint16_t) * CHAR_BIT,
2802 lttng_alignof(uint32_t) * CHAR_BIT,
2803 lttng_alignof(uint64_t) * CHAR_BIT,
a9afe705
MD		 2804 sizeof(unsigned long) * CHAR_BIT,
2805 lttng_alignof(unsigned long) * CHAR_BIT,
c6c9e10f
MD		 2806 CTF_SPEC_MAJOR,
2807 CTF_SPEC_MINOR,
d793d5e1 2808 uuid_s,
5214fa50 2809#if __BYTE_ORDER == __BIG_ENDIAN
d793d5e1
MD		 2810 "be"
2811#else
2812 "le"
2813#endif
2814 );
2815 if (ret)
2816 goto end;
2817
99dc9597
MD		 2818 ret = lttng_metadata_printf(session,
2819 "env {\n"
a6058143 2820 " hostname = \"%s\";\n"
c6c9e10f 2821 " domain = \"kernel\";\n"
99dc9597 2822 " sysname = \"%s\";\n"
c6c9e10f
MD		 2823 " kernel_release = \"%s\";\n"
2824 " kernel_version = \"%s\";\n"
2825 " tracer_name = \"lttng-modules\";\n"
2826 " tracer_major = %d;\n"
2827 " tracer_minor = %d;\n"
2828 " tracer_patchlevel = %d;\n"
3eb95be4 2829 " trace_buffering_scheme = \"global\";\n",
3d0d43db 2830 current->nsproxy->uts_ns->name.nodename,
99dc9597
MD		 2831 utsname()->sysname,
2832 utsname()->release,
c6c9e10f
MD		 2833 utsname()->version,
2834 LTTNG_MODULES_MAJOR_VERSION,
2835 LTTNG_MODULES_MINOR_VERSION,
2836 LTTNG_MODULES_PATCHLEVEL_VERSION
99dc9597
MD		 2837 );
2838 if (ret)
2839 goto end;
2840
1c88f269
JR		 2841 ret = print_metadata_escaped_field(session, "trace_name", session->name);
2842 if (ret)
2843 goto end;
2844 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
2845 session->creation_time);
3eb95be4
JR		 2846 if (ret)
2847 goto end;
2848
c88f762e
GB		 2849 /* Add the product UUID to the 'env' section */
2850 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
2851 if (product_uuid) {
2852 ret = lttng_metadata_printf(session,
2853 " product_uuid = \"%s\";\n",
2854 product_uuid
2855 );
2856 if (ret)
2857 goto end;
2858 }
2859
2860 /* Close the 'env' section */
3eb95be4
JR		 2861 ret = lttng_metadata_printf(session, "};\n\n");
2862 if (ret)
2863 goto end;
2864
a3ccff4f
MD		 2865 ret = lttng_metadata_printf(session,
2866 "clock {\n"
2754583e
MD		 2867 " name = \"%s\";\n",
2868 trace_clock_name()
a82c63f1
MD		 2869 );
2870 if (ret)
2871 goto end;
2872
2873 if (!trace_clock_uuid(clock_uuid_s)) {
2874 ret = lttng_metadata_printf(session,
7c27cb17 2875 " uuid = \"%s\";\n",
a82c63f1
MD		 2876 clock_uuid_s
2877 );
2878 if (ret)
2879 goto end;
2880 }
2881
2882 ret = lttng_metadata_printf(session,
2754583e 2883 " description = \"%s\";\n"
a3ccff4f
MD		 2884 " freq = %llu; /* Frequency, in Hz */\n"
2885 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
8967b2a3 2886 " offset = %lld;\n"
a3ccff4f 2887 "};\n\n",
2754583e 2888 trace_clock_description(),
a3ccff4f 2889 (unsigned long long) trace_clock_freq(),
8967b2a3 2890 (long long) measure_clock_offset()
a3ccff4f
MD		 2891 );
2892 if (ret)
2893 goto end;
2894
2895 ret = lttng_metadata_printf(session,
2896 "typealias integer {\n"
2897 " size = 27; align = 1; signed = false;\n"
2754583e 2898 " map = clock.%s.value;\n"
a3ccff4f
MD		 2899 "} := uint27_clock_monotonic_t;\n"
2900 "\n"
2901 "typealias integer {\n"
2902 " size = 32; align = %u; signed = false;\n"
2754583e 2903 " map = clock.%s.value;\n"
a3ccff4f
MD		 2904 "} := uint32_clock_monotonic_t;\n"
2905 "\n"
2906 "typealias integer {\n"
2907 " size = 64; align = %u; signed = false;\n"
2754583e 2908 " map = clock.%s.value;\n"
a3ccff4f 2909 "} := uint64_clock_monotonic_t;\n\n",
2754583e 2910 trace_clock_name(),
a3ccff4f 2911 lttng_alignof(uint32_t) * CHAR_BIT,
2754583e
MD		 2912 trace_clock_name(),
2913 lttng_alignof(uint64_t) * CHAR_BIT,
2914 trace_clock_name()
a3ccff4f
MD		 2915 );
2916 if (ret)
2917 goto end;
2918
a90917c3 2919 ret = _lttng_stream_packet_context_declare(session);
9115fbdc
MD		 2920 if (ret)
2921 goto end;
2922
a90917c3 2923 ret = _lttng_event_header_declare(session);
9115fbdc
MD		 2924 if (ret)
2925 goto end;
2926
c099397a
MD		 2927skip_session:
2928 list_for_each_entry(chan, &session->chan, list) {
a90917c3 2929 ret = _lttng_channel_metadata_statedump(session, chan);
c099397a
MD		 2930 if (ret)
2931 goto end;
2932 }
2933
2934 list_for_each_entry(event, &session->events, list) {
a90917c3 2935 ret = _lttng_event_metadata_statedump(session, event->chan, event);
c099397a
MD		 2936 if (ret)
2937 goto end;
2938 }
2939 session->metadata_dumped = 1;
2940end:
8b97fd42 2941 lttng_metadata_end(session);
c099397a
MD		 2942 return ret;
2943}
2944
c0e31d2e 2945/**
a90917c3 2946 * lttng_transport_register - LTT transport registration
c0e31d2e
MD		 2947 * @transport: transport structure
2948 *
2949 * Registers a transport which can be used as output to extract the data out of
2950 * LTTng. The module calling this registration function must ensure that no
2951 * trap-inducing code will be executed by the transport functions. E.g.
263b6c88 2952 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
c0e31d2e 2953 * is made visible to the transport function. This registration acts as a
263b6c88 2954 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
c0e31d2e
MD		 2955 * after its registration must it synchronize the TLBs.
2956 */
a90917c3 2957void lttng_transport_register(struct lttng_transport *transport)
c0e31d2e
MD		 2958{
2959 /*
2960 * Make sure no page fault can be triggered by the module about to be
2961 * registered. We deal with this here so we don't have to call
263b6c88 2962 * vmalloc_sync_mappings() in each module's init.
c0e31d2e 2963 */
263b6c88 2964 wrapper_vmalloc_sync_mappings();
c0e31d2e
MD		 2965
2966 mutex_lock(&sessions_mutex);
a90917c3 2967 list_add_tail(&transport->node, &lttng_transport_list);
c0e31d2e
MD		 2968 mutex_unlock(&sessions_mutex);
2969}
a90917c3 2970EXPORT_SYMBOL_GPL(lttng_transport_register);
c0e31d2e
MD		 2971
2972/**
a90917c3 2973 * lttng_transport_unregister - LTT transport unregistration
c0e31d2e
MD		 2974 * @transport: transport structure
2975 */
a90917c3 2976void lttng_transport_unregister(struct lttng_transport *transport)
c0e31d2e
MD		 2977{
2978 mutex_lock(&sessions_mutex);
2979 list_del(&transport->node);
2980 mutex_unlock(&sessions_mutex);
2981}
a90917c3 2982EXPORT_SYMBOL_GPL(lttng_transport_unregister);
c0e31d2e 2983
894ce5dc 2984#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
1e367326
MD		 2985
2986enum cpuhp_state lttng_hp_prepare;
2987enum cpuhp_state lttng_hp_online;
2988
2989static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
2990{
2991 struct lttng_cpuhp_node *lttng_node;
2992
2993 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2994 switch (lttng_node->component) {
2995 case LTTNG_RING_BUFFER_FRONTEND:
2996 return 0;
2997 case LTTNG_RING_BUFFER_BACKEND:
2998 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
2999 case LTTNG_RING_BUFFER_ITER:
3000 return 0;
3001 case LTTNG_CONTEXT_PERF_COUNTERS:
3002 return 0;
3003 default:
3004 return -EINVAL;
3005 }
3006}
3007
3008static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
3009{
3010 struct lttng_cpuhp_node *lttng_node;
3011
3012 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3013 switch (lttng_node->component) {
3014 case LTTNG_RING_BUFFER_FRONTEND:
3015 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
3016 case LTTNG_RING_BUFFER_BACKEND:
3017 return 0;
3018 case LTTNG_RING_BUFFER_ITER:
3019 return 0;
3020 case LTTNG_CONTEXT_PERF_COUNTERS:
3021 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
3022 default:
3023 return -EINVAL;
3024 }
3025}
3026
3027static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
3028{
3029 struct lttng_cpuhp_node *lttng_node;
3030
3031 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3032 switch (lttng_node->component) {
3033 case LTTNG_RING_BUFFER_FRONTEND:
3034 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
3035 case LTTNG_RING_BUFFER_BACKEND:
3036 return 0;
3037 case LTTNG_RING_BUFFER_ITER:
3038 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
3039 case LTTNG_CONTEXT_PERF_COUNTERS:
3040 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
3041 default:
3042 return -EINVAL;
3043 }
3044}
3045
3046static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
3047{
3048 struct lttng_cpuhp_node *lttng_node;
3049
3050 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3051 switch (lttng_node->component) {
3052 case LTTNG_RING_BUFFER_FRONTEND:
3053 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
3054 case LTTNG_RING_BUFFER_BACKEND:
3055 return 0;
3056 case LTTNG_RING_BUFFER_ITER:
3057 return 0;
3058 case LTTNG_CONTEXT_PERF_COUNTERS:
3059 return 0;
3060 default:
3061 return -EINVAL;
3062 }
3063}
3064
3065static int __init lttng_init_cpu_hotplug(void)
3066{
3067 int ret;
3068
3069 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
3070 lttng_hotplug_prepare,
3071 lttng_hotplug_dead);
3072 if (ret < 0) {
3073 return ret;
3074 }
3075 lttng_hp_prepare = ret;
3076 lttng_rb_set_hp_prepare(ret);
3077
3078 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
3079 lttng_hotplug_online,
3080 lttng_hotplug_offline);
3081 if (ret < 0) {
3082 cpuhp_remove_multi_state(lttng_hp_prepare);
3083 lttng_hp_prepare = 0;
3084 return ret;
3085 }
3086 lttng_hp_online = ret;
3087 lttng_rb_set_hp_online(ret);
3088
3089 return 0;
3090}
3091
3092static void __exit lttng_exit_cpu_hotplug(void)
3093{
3094 lttng_rb_set_hp_online(0);
3095 cpuhp_remove_multi_state(lttng_hp_online);
3096 lttng_rb_set_hp_prepare(0);
3097 cpuhp_remove_multi_state(lttng_hp_prepare);
3098}
3099
1ee63d8d 3100#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
1e367326
MD		 3101static int lttng_init_cpu_hotplug(void)
3102{
3103 return 0;
3104}
3105static void lttng_exit_cpu_hotplug(void)
3106{
3107}
1ee63d8d 3108#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
1e367326
MD		 3109
3110
a90917c3 3111static int __init lttng_events_init(void)
4e3c1b9b 3112{
1c25284c
MD		 3113 int ret;
3114
453b2495
JD		 3115 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
3116 if (ret)
3117 return ret;
389d7070 3118 ret = wrapper_get_pfnblock_flags_mask_init();
36561775
MD		 3119 if (ret)
3120 return ret;
3121 ret = wrapper_get_pageblock_flags_mask_init();
114667d5
MD		 3122 if (ret)
3123 return ret;
3124 ret = lttng_probes_init();
389d7070
MD		 3125 if (ret)
3126 return ret;
07dfc1d0 3127 ret = lttng_context_init();
20591cf7
MD		 3128 if (ret)
3129 return ret;
07dfc1d0
MD		 3130 ret = lttng_tracepoint_init();
3131 if (ret)
3132 goto error_tp;
a90917c3 3133 event_cache = KMEM_CACHE(lttng_event, 0);
20591cf7
MD		 3134 if (!event_cache) {
3135 ret = -ENOMEM;
3136 goto error_kmem;
3137 }
80996790 3138 ret = lttng_abi_init();
02119ee5
MD		 3139 if (ret)
3140 goto error_abi;
0c956676
MD		 3141 ret = lttng_logger_init();
3142 if (ret)
3143 goto error_logger;
1e367326
MD		 3144 ret = lttng_init_cpu_hotplug();
3145 if (ret)
3146 goto error_hotplug;
101215b7 3147 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3148 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3149 __stringify(LTTNG_MODULES_MINOR_VERSION),
3150 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3151 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3152 LTTNG_VERSION_NAME,
3153#ifdef LTTNG_EXTRA_VERSION_GIT
3154 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3155#else
3156 "",
3157#endif
3158#ifdef LTTNG_EXTRA_VERSION_NAME
3159 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3160#else
3161 "");
3162#endif
4e3c1b9b 3163 return 0;
0c956676 3164
1e367326
MD		 3165error_hotplug:
3166 lttng_logger_exit();
0c956676
MD		 3167error_logger:
3168 lttng_abi_exit();
02119ee5 3169error_abi:
1c25284c 3170 kmem_cache_destroy(event_cache);
20591cf7
MD		 3171error_kmem:
3172 lttng_tracepoint_exit();
07dfc1d0
MD		 3173error_tp:
3174 lttng_context_exit();
101215b7 3175 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3176 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3177 __stringify(LTTNG_MODULES_MINOR_VERSION),
3178 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3179 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3180 LTTNG_VERSION_NAME,
3181#ifdef LTTNG_EXTRA_VERSION_GIT
3182 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3183#else
3184 "",
3185#endif
3186#ifdef LTTNG_EXTRA_VERSION_NAME
3187 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3188#else
3189 "");
3190#endif
1c25284c 3191 return ret;
4e3c1b9b
MD		 3192}
3193
a90917c3 3194module_init(lttng_events_init);
11b5a3c2 3195
a90917c3 3196static void __exit lttng_events_exit(void)
4e3c1b9b 3197{
a90917c3 3198 struct lttng_session *session, *tmpsession;
92e94819 3199
1e367326 3200 lttng_exit_cpu_hotplug();
0c956676 3201 lttng_logger_exit();
80996790 3202 lttng_abi_exit();
92e94819 3203 list_for_each_entry_safe(session, tmpsession, &sessions, list)
a90917c3 3204 lttng_session_destroy(session);
11b5a3c2 3205 kmem_cache_destroy(event_cache);
20591cf7 3206 lttng_tracepoint_exit();
07dfc1d0 3207 lttng_context_exit();
101215b7 3208 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3209 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3210 __stringify(LTTNG_MODULES_MINOR_VERSION),
3211 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3212 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3213 LTTNG_VERSION_NAME,
3214#ifdef LTTNG_EXTRA_VERSION_GIT
3215 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3216#else
3217 "",
3218#endif
3219#ifdef LTTNG_EXTRA_VERSION_NAME
3220 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3221#else
3222 "");
3223#endif
4e3c1b9b 3224}
92e94819 3225
a90917c3 3226module_exit(lttng_events_exit);
11b5a3c2 3227
7ca11e77 3228#include <generated/patches.h>
101215b7
MJ		 3229#ifdef LTTNG_EXTRA_VERSION_GIT
3230MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
3231#endif
3232#ifdef LTTNG_EXTRA_VERSION_NAME
3233MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
3234#endif
92e94819
MD		 3235MODULE_LICENSE("GPL and additional rights");
3236MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
1c124020 3237MODULE_DESCRIPTION("LTTng tracer");
9a9973ef
MD		 3238MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
3239 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
309370e2
MD		 3240 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
3241 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
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