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fix: tie compaction probe build to CONFIG_COMPACTION
[lttng-modules.git] / lttng-events.c
CommitLineData
9f36eaed
MJ		 1/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
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
8b7bb83e 32#include <wrapper/uuid.h>
ea53823c 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>
241ae9a8
MD		 38#include <lttng-kernel-version.h>
39#include <lttng-events.h>
40#include <lttng-tracer.h>
41#include <lttng-abi-old.h>
5214fa50 42#include <lttng-endian.h>
4993071a 43#include <lttng-string-utils.h>
1d00109f 44#include <wrapper/compiler_attributes.h>
64af2437
MD		 45#include <wrapper/ringbuffer/backend.h>
46#include <wrapper/ringbuffer/frontend.h>
72dc372e 47#include <wrapper/time.h>
4e3c1b9b 48
74b3b9d3
MJ		 49#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,16,0))
50#include <linux/stdarg.h>
51#else
52#include <stdarg.h>
53#endif
54
d83004aa
JD		 55#define METADATA_CACHE_DEFAULT_SIZE 4096
56
4e3c1b9b 57static LIST_HEAD(sessions);
a90917c3 58static LIST_HEAD(lttng_transport_list);
d83004aa
JD		 59/*
60 * Protect the sessions and metadata caches.
61 */
4e3c1b9b
MD		 62static DEFINE_MUTEX(sessions_mutex);
63static struct kmem_cache *event_cache;
64
3c997079
MD		 65static void lttng_session_lazy_sync_enablers(struct lttng_session *session);
66static void lttng_session_sync_enablers(struct lttng_session *session);
67static void lttng_enabler_destroy(struct lttng_enabler *enabler);
68
a90917c3
MD		 69static void _lttng_event_destroy(struct lttng_event *event);
70static void _lttng_channel_destroy(struct lttng_channel *chan);
71static int _lttng_event_unregister(struct lttng_event *event);
c099397a 72static
a90917c3
MD		 73int _lttng_event_metadata_statedump(struct lttng_session *session,
74 struct lttng_channel *chan,
75 struct lttng_event *event);
c099397a 76static
a90917c3 77int _lttng_session_metadata_statedump(struct lttng_session *session);
d83004aa
JD		 78static
79void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
f513b2bf
MD		 80static
81int _lttng_field_statedump(struct lttng_session *session,
82 const struct lttng_event_field *field,
83 size_t nesting);
c099397a 84
c099397a 85void synchronize_trace(void)
abcca994 86{
78f56ae3
MJ		 87#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,1,0) || \
88 LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
92da05ce
MJ		 89 synchronize_rcu();
90#else
abcca994 91 synchronize_sched();
92da05ce
MJ		 92#endif
93
2d042821 94#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0))
b8590f40
MD		 95#ifdef CONFIG_PREEMPT_RT_FULL
96 synchronize_rcu();
97#endif
2d042821 98#else /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
abcca994
MD		 99#ifdef CONFIG_PREEMPT_RT
100 synchronize_rcu();
101#endif
2d042821 102#endif /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
abcca994
MD		 103}
104
3c997079
MD		 105void lttng_lock_sessions(void)
106{
107 mutex_lock(&sessions_mutex);
108}
109
110void lttng_unlock_sessions(void)
111{
112 mutex_unlock(&sessions_mutex);
113}
114
115/*
116 * Called with sessions lock held.
117 */
118int lttng_session_active(void)
119{
120 struct lttng_session *iter;
121
122 list_for_each_entry(iter, &sessions, list) {
123 if (iter->active)
124 return 1;
125 }
126 return 0;
127}
128
a90917c3 129struct lttng_session *lttng_session_create(void)
4e3c1b9b 130{
a90917c3 131 struct lttng_session *session;
d83004aa 132 struct lttng_metadata_cache *metadata_cache;
3c997079 133 int i;
4e3c1b9b
MD		 134
135 mutex_lock(&sessions_mutex);
48f5e0b5 136 session = lttng_kvzalloc(sizeof(struct lttng_session), GFP_KERNEL);
4e3c1b9b 137 if (!session)
d83004aa 138 goto err;
4e3c1b9b 139 INIT_LIST_HEAD(&session->chan);
f3d01b96 140 INIT_LIST_HEAD(&session->events);
8b7bb83e 141 lttng_guid_gen(&session->uuid);
d83004aa
JD		 142
143 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
144 GFP_KERNEL);
145 if (!metadata_cache)
146 goto err_free_session;
0ca42eb7 147 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
d83004aa
JD		 148 if (!metadata_cache->data)
149 goto err_free_cache;
150 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
151 kref_init(&metadata_cache->refcount);
92d9f5e6 152 mutex_init(&metadata_cache->lock);
d83004aa
JD		 153 session->metadata_cache = metadata_cache;
154 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
a36580d5
MD		 155 memcpy(&metadata_cache->uuid, &session->uuid,
156 sizeof(metadata_cache->uuid));
3c997079
MD		 157 INIT_LIST_HEAD(&session->enablers_head);
158 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
159 INIT_HLIST_HEAD(&session->events_ht.table[i]);
4e3c1b9b 160 list_add(&session->list, &sessions);
d1f652f8
MD		 161 session->pid_tracker.session = session;
162 session->pid_tracker.tracker_type = TRACKER_PID;
163 session->vpid_tracker.session = session;
164 session->vpid_tracker.tracker_type = TRACKER_VPID;
165 session->uid_tracker.session = session;
166 session->uid_tracker.tracker_type = TRACKER_UID;
167 session->vuid_tracker.session = session;
168 session->vuid_tracker.tracker_type = TRACKER_VUID;
169 session->gid_tracker.session = session;
170 session->gid_tracker.tracker_type = TRACKER_GID;
171 session->vgid_tracker.session = session;
172 session->vgid_tracker.tracker_type = TRACKER_VGID;
4e3c1b9b
MD		 173 mutex_unlock(&sessions_mutex);
174 return session;
d83004aa
JD		 175
176err_free_cache:
177 kfree(metadata_cache);
178err_free_session:
48f5e0b5 179 lttng_kvfree(session);
d83004aa
JD		 180err:
181 mutex_unlock(&sessions_mutex);
182 return NULL;
183}
184
185void metadata_cache_destroy(struct kref *kref)
186{
187 struct lttng_metadata_cache *cache =
188 container_of(kref, struct lttng_metadata_cache, refcount);
a606b6e8 189 vfree(cache->data);
d83004aa 190 kfree(cache);
4e3c1b9b
MD		 191}
192
a90917c3 193void lttng_session_destroy(struct lttng_session *session)
4e3c1b9b 194{
a90917c3
MD		 195 struct lttng_channel *chan, *tmpchan;
196 struct lttng_event *event, *tmpevent;
d83004aa 197 struct lttng_metadata_stream *metadata_stream;
3c997079 198 struct lttng_enabler *enabler, *tmpenabler;
dda6a249 199 int ret;
4e3c1b9b
MD		 200
201 mutex_lock(&sessions_mutex);
a8f2d0c7 202 WRITE_ONCE(session->active, 0);
1ec65de1
MD		 203 list_for_each_entry(chan, &session->chan, list) {
204 ret = lttng_syscalls_unregister(chan);
205 WARN_ON(ret);
206 }
dda6a249 207 list_for_each_entry(event, &session->events, list) {
a90917c3 208 ret = _lttng_event_unregister(event);
dda6a249
MD		 209 WARN_ON(ret);
210 }
abcca994 211 synchronize_trace(); /* Wait for in-flight events to complete */
ad594e3a
MD		 212 list_for_each_entry(chan, &session->chan, list) {
213 ret = lttng_syscalls_destroy(chan);
214 WARN_ON(ret);
215 }
3c997079
MD		 216 list_for_each_entry_safe(enabler, tmpenabler,
217 &session->enablers_head, node)
218 lttng_enabler_destroy(enabler);
4e3c1b9b 219 list_for_each_entry_safe(event, tmpevent, &session->events, list)
a90917c3 220 _lttng_event_destroy(event);
d83004aa
JD		 221 list_for_each_entry_safe(chan, tmpchan, &session->chan, list) {
222 BUG_ON(chan->channel_type == METADATA_CHANNEL);
a90917c3 223 _lttng_channel_destroy(chan);
d83004aa 224 }
5a4afa8a 225 mutex_lock(&session->metadata_cache->lock);
d83004aa
JD		 226 list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
227 _lttng_metadata_channel_hangup(metadata_stream);
5a4afa8a 228 mutex_unlock(&session->metadata_cache->lock);
d1f652f8
MD		 229 lttng_id_tracker_destroy(&session->pid_tracker, false);
230 lttng_id_tracker_destroy(&session->vpid_tracker, false);
231 lttng_id_tracker_destroy(&session->uid_tracker, false);
232 lttng_id_tracker_destroy(&session->vuid_tracker, false);
233 lttng_id_tracker_destroy(&session->gid_tracker, false);
234 lttng_id_tracker_destroy(&session->vgid_tracker, false);
d83004aa 235 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
4e3c1b9b
MD		 236 list_del(&session->list);
237 mutex_unlock(&sessions_mutex);
48f5e0b5 238 lttng_kvfree(session);
4e3c1b9b
MD		 239}
240
601252cf
MD		 241int lttng_session_statedump(struct lttng_session *session)
242{
243 int ret;
244
245 mutex_lock(&sessions_mutex);
246 ret = lttng_statedump_start(session);
247 mutex_unlock(&sessions_mutex);
248 return ret;
249}
250
a90917c3 251int lttng_session_enable(struct lttng_session *session)
c0e31d2e
MD		 252{
253 int ret = 0;
a90917c3 254 struct lttng_channel *chan;
c0e31d2e
MD		 255
256 mutex_lock(&sessions_mutex);
257 if (session->active) {
258 ret = -EBUSY;
259 goto end;
260 }
c099397a 261
3c997079
MD		 262 /* Set transient enabler state to "enabled" */
263 session->tstate = 1;
264
4ef81e4a
MD		 265 /* We need to sync enablers with session before activation. */
266 lttng_session_sync_enablers(session);
267
c099397a
MD		 268 /*
269 * Snapshot the number of events per channel to know the type of header
270 * we need to use.
271 */
272 list_for_each_entry(chan, &session->chan, list) {
273 if (chan->header_type)
274 continue; /* don't change it if session stop/restart */
275 if (chan->free_event_id < 31)
276 chan->header_type = 1; /* compact */
277 else
278 chan->header_type = 2; /* large */
279 }
280
64af2437 281 /* Clear each stream's quiescent state. */
09b93db9
MD		 282 list_for_each_entry(chan, &session->chan, list) {
283 if (chan->channel_type != METADATA_CHANNEL)
284 lib_ring_buffer_clear_quiescent_channel(chan->chan);
285 }
64af2437 286
a8f2d0c7
MJ		 287 WRITE_ONCE(session->active, 1);
288 WRITE_ONCE(session->been_active, 1);
a90917c3 289 ret = _lttng_session_metadata_statedump(session);
c337ddc2 290 if (ret) {
a8f2d0c7 291 WRITE_ONCE(session->active, 0);
c337ddc2
MD		 292 goto end;
293 }
294 ret = lttng_statedump_start(session);
360f38ea 295 if (ret)
a8f2d0c7 296 WRITE_ONCE(session->active, 0);
c0e31d2e
MD		 297end:
298 mutex_unlock(&sessions_mutex);
11b5a3c2 299 return ret;
c0e31d2e
MD		 300}
301
a90917c3 302int lttng_session_disable(struct lttng_session *session)
c0e31d2e
MD		 303{
304 int ret = 0;
64af2437 305 struct lttng_channel *chan;
c0e31d2e
MD		 306
307 mutex_lock(&sessions_mutex);
308 if (!session->active) {
309 ret = -EBUSY;
310 goto end;
311 }
a8f2d0c7 312 WRITE_ONCE(session->active, 0);
3c997079
MD		 313
314 /* Set transient enabler state to "disabled" */
315 session->tstate = 0;
316 lttng_session_sync_enablers(session);
64af2437
MD		 317
318 /* Set each stream's quiescent state. */
09b93db9
MD		 319 list_for_each_entry(chan, &session->chan, list) {
320 if (chan->channel_type != METADATA_CHANNEL)
321 lib_ring_buffer_set_quiescent_channel(chan->chan);
322 }
c0e31d2e
MD		 323end:
324 mutex_unlock(&sessions_mutex);
11b5a3c2 325 return ret;
c0e31d2e
MD		 326}
327
9616f0bf
JD		 328int lttng_session_metadata_regenerate(struct lttng_session *session)
329{
330 int ret = 0;
331 struct lttng_channel *chan;
332 struct lttng_event *event;
333 struct lttng_metadata_cache *cache = session->metadata_cache;
334 struct lttng_metadata_stream *stream;
335
336 mutex_lock(&sessions_mutex);
337 if (!session->active) {
338 ret = -EBUSY;
339 goto end;
340 }
341
342 mutex_lock(&cache->lock);
343 memset(cache->data, 0, cache->cache_alloc);
344 cache->metadata_written = 0;
345 cache->version++;
346 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) {
347 stream->metadata_out = 0;
348 stream->metadata_in = 0;
349 }
350 mutex_unlock(&cache->lock);
351
352 session->metadata_dumped = 0;
353 list_for_each_entry(chan, &session->chan, list) {
354 chan->metadata_dumped = 0;
355 }
356
357 list_for_each_entry(event, &session->events, list) {
358 event->metadata_dumped = 0;
359 }
360
361 ret = _lttng_session_metadata_statedump(session);
362
363end:
364 mutex_unlock(&sessions_mutex);
365 return ret;
366}
367
a90917c3 368int lttng_channel_enable(struct lttng_channel *channel)
e64957da 369{
3c997079 370 int ret = 0;
e64957da 371
3c997079
MD		 372 mutex_lock(&sessions_mutex);
373 if (channel->channel_type == METADATA_CHANNEL) {
374 ret = -EPERM;
375 goto end;
376 }
377 if (channel->enabled) {
378 ret = -EEXIST;
379 goto end;
380 }
381 /* Set transient enabler state to "enabled" */
382 channel->tstate = 1;
383 lttng_session_sync_enablers(channel->session);
384 /* Set atomically the state to "enabled" */
a8f2d0c7 385 WRITE_ONCE(channel->enabled, 1);
3c997079
MD		 386end:
387 mutex_unlock(&sessions_mutex);
388 return ret;
e64957da
MD		 389}
390
a90917c3 391int lttng_channel_disable(struct lttng_channel *channel)
e64957da 392{
3c997079 393 int ret = 0;
e64957da 394
3c997079
MD		 395 mutex_lock(&sessions_mutex);
396 if (channel->channel_type == METADATA_CHANNEL) {
397 ret = -EPERM;
398 goto end;
399 }
400 if (!channel->enabled) {
401 ret = -EEXIST;
402 goto end;
403 }
404 /* Set atomically the state to "disabled" */
a8f2d0c7 405 WRITE_ONCE(channel->enabled, 0);
3c997079
MD		 406 /* Set transient enabler state to "enabled" */
407 channel->tstate = 0;
408 lttng_session_sync_enablers(channel->session);
409end:
410 mutex_unlock(&sessions_mutex);
411 return ret;
e64957da
MD		 412}
413
a90917c3 414int lttng_event_enable(struct lttng_event *event)
e64957da 415{
3c997079 416 int ret = 0;
e64957da 417
3c997079
MD		 418 mutex_lock(&sessions_mutex);
419 if (event->chan->channel_type == METADATA_CHANNEL) {
420 ret = -EPERM;
421 goto end;
422 }
423 if (event->enabled) {
424 ret = -EEXIST;
425 goto end;
426 }
a0493bef
MD		 427 switch (event->instrumentation) {
428 case LTTNG_KERNEL_TRACEPOINT:
429 case LTTNG_KERNEL_SYSCALL:
430 ret = -EINVAL;
431 break;
432 case LTTNG_KERNEL_KPROBE:
149b9a9d 433 case LTTNG_KERNEL_UPROBE:
a0493bef 434 case LTTNG_KERNEL_NOOP:
a8f2d0c7 435 WRITE_ONCE(event->enabled, 1);
a0493bef
MD		 436 break;
437 case LTTNG_KERNEL_KRETPROBE:
438 ret = lttng_kretprobes_event_enable_state(event, 1);
439 break;
1d00109f
MJ		 440 case LTTNG_KERNEL_FUNCTION:
441 lttng_fallthrough;
a0493bef
MD		 442 default:
443 WARN_ON_ONCE(1);
444 ret = -EINVAL;
445 }
3c997079
MD		 446end:
447 mutex_unlock(&sessions_mutex);
448 return ret;
e64957da
MD		 449}
450
a90917c3 451int lttng_event_disable(struct lttng_event *event)
e64957da 452{
3c997079 453 int ret = 0;
e64957da 454
3c997079
MD		 455 mutex_lock(&sessions_mutex);
456 if (event->chan->channel_type == METADATA_CHANNEL) {
457 ret = -EPERM;
458 goto end;
459 }
460 if (!event->enabled) {
461 ret = -EEXIST;
462 goto end;
463 }
a0493bef
MD		 464 switch (event->instrumentation) {
465 case LTTNG_KERNEL_TRACEPOINT:
466 case LTTNG_KERNEL_SYSCALL:
467 ret = -EINVAL;
468 break;
469 case LTTNG_KERNEL_KPROBE:
149b9a9d 470 case LTTNG_KERNEL_UPROBE:
a0493bef 471 case LTTNG_KERNEL_NOOP:
a8f2d0c7 472 WRITE_ONCE(event->enabled, 0);
a0493bef
MD		 473 break;
474 case LTTNG_KERNEL_KRETPROBE:
475 ret = lttng_kretprobes_event_enable_state(event, 0);
476 break;
1d00109f
MJ		 477 case LTTNG_KERNEL_FUNCTION:
478 lttng_fallthrough;
a0493bef
MD		 479 default:
480 WARN_ON_ONCE(1);
481 ret = -EINVAL;
482 }
3c997079
MD		 483end:
484 mutex_unlock(&sessions_mutex);
485 return ret;
e64957da
MD		 486}
487
a90917c3 488static struct lttng_transport *lttng_transport_find(const char *name)
f3d01b96 489{
a90917c3 490 struct lttng_transport *transport;
f3d01b96 491
a90917c3 492 list_for_each_entry(transport, &lttng_transport_list, node) {
f3d01b96
MD		 493 if (!strcmp(transport->name, name))
494 return transport;
495 }
496 return NULL;
497}
498
a90917c3 499struct lttng_channel *lttng_channel_create(struct lttng_session *session,
5dbbdb43
MD		 500 const char *transport_name,
501 void *buf_addr,
4e3c1b9b
MD		 502 size_t subbuf_size, size_t num_subbuf,
503 unsigned int switch_timer_interval,
d83004aa
JD		 504 unsigned int read_timer_interval,
505 enum channel_type channel_type)
4e3c1b9b 506{
a90917c3
MD		 507 struct lttng_channel *chan;
508 struct lttng_transport *transport = NULL;
4e3c1b9b
MD		 509
510 mutex_lock(&sessions_mutex);
d83004aa 511 if (session->been_active && channel_type != METADATA_CHANNEL)
e5382b6d 512 goto active; /* Refuse to add channel to active session */
a90917c3 513 transport = lttng_transport_find(transport_name);
f3d01b96
MD		 514 if (!transport) {
515 printk(KERN_WARNING "LTTng transport %s not found\n",
516 transport_name);
c0e31d2e 517 goto notransport;
f3d01b96 518 }
a33c9927
MD		 519 if (!try_module_get(transport->owner)) {
520 printk(KERN_WARNING "LTT : Can't lock transport module.\n");
521 goto notransport;
522 }
a90917c3 523 chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL);
4e3c1b9b 524 if (!chan)
c0e31d2e 525 goto nomem;
4e3c1b9b 526 chan->session = session;
05d32c64 527 chan->id = session->free_chan_id++;
3b731ab1 528 chan->ops = &transport->ops;
125b4df4
MD		 529 /*
530 * Note: the channel creation op already writes into the packet
531 * headers. Therefore the "chan" information used as input
532 * should be already accessible.
533 */
5f5ddf01
MD		 534 chan->chan = transport->ops.channel_create(transport_name,
535 chan, buf_addr, subbuf_size, num_subbuf,
536 switch_timer_interval, read_timer_interval);
f3d01b96
MD		 537 if (!chan->chan)
538 goto create_error;
3c997079 539 chan->tstate = 1;
e64957da 540 chan->enabled = 1;
a33c9927 541 chan->transport = transport;
d83004aa 542 chan->channel_type = channel_type;
4e3c1b9b
MD		 543 list_add(&chan->list, &session->chan);
544 mutex_unlock(&sessions_mutex);
545 return chan;
546
f3d01b96
MD		 547create_error:
548 kfree(chan);
c0e31d2e 549nomem:
a33c9927
MD		 550 if (transport)
551 module_put(transport->owner);
c0e31d2e 552notransport:
e5382b6d 553active:
4e3c1b9b
MD		 554 mutex_unlock(&sessions_mutex);
555 return NULL;
556}
557
558/*
d83004aa
JD		 559 * Only used internally at session destruction for per-cpu channels, and
560 * when metadata channel is released.
561 * Needs to be called with sessions mutex held.
4e3c1b9b 562 */
aa7c23a9 563static
a90917c3 564void _lttng_channel_destroy(struct lttng_channel *chan)
4e3c1b9b 565{
11b5a3c2 566 chan->ops->channel_destroy(chan->chan);
a33c9927 567 module_put(chan->transport->owner);
4e3c1b9b 568 list_del(&chan->list);
8070f5c0 569 lttng_destroy_context(chan->ctx);
4e3c1b9b
MD		 570 kfree(chan);
571}
572
d83004aa
JD		 573void lttng_metadata_channel_destroy(struct lttng_channel *chan)
574{
575 BUG_ON(chan->channel_type != METADATA_CHANNEL);
576
577 /* Protect the metadata cache with the sessions_mutex. */
578 mutex_lock(&sessions_mutex);
579 _lttng_channel_destroy(chan);
580 mutex_unlock(&sessions_mutex);
581}
582EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
583
584static
585void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
586{
587 stream->finalized = 1;
588 wake_up_interruptible(&stream->read_wait);
589}
590
e5382b6d
MD		 591/*
592 * Supports event creation while tracing session is active.
3c997079 593 * Needs to be called with sessions mutex held.
e5382b6d 594 */
3c997079
MD		 595struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
596 struct lttng_kernel_event *event_param,
597 void *filter,
598 const struct lttng_event_desc *event_desc,
599 enum lttng_kernel_instrumentation itype)
4e3c1b9b 600{
3c997079 601 struct lttng_session *session = chan->session;
a90917c3 602 struct lttng_event *event;
3c997079
MD		 603 const char *event_name;
604 struct hlist_head *head;
605 size_t name_len;
606 uint32_t hash;
3d084699 607 int ret;
4e3c1b9b 608
abc0446a 609 if (chan->free_event_id == -1U) {
4cf0bf51 610 ret = -EMFILE;
e5382b6d 611 goto full;
abc0446a 612 }
3c997079
MD		 613
614 switch (itype) {
615 case LTTNG_KERNEL_TRACEPOINT:
616 event_name = event_desc->name;
617 break;
618 case LTTNG_KERNEL_KPROBE:
149b9a9d 619 case LTTNG_KERNEL_UPROBE:
3c997079 620 case LTTNG_KERNEL_KRETPROBE:
3c997079 621 case LTTNG_KERNEL_NOOP:
33a39a3c 622 case LTTNG_KERNEL_SYSCALL:
3c997079
MD		 623 event_name = event_param->name;
624 break;
1d00109f
MJ		 625 case LTTNG_KERNEL_FUNCTION:
626 lttng_fallthrough;
3c997079
MD		 627 default:
628 WARN_ON_ONCE(1);
629 ret = -EINVAL;
630 goto type_error;
631 }
632 name_len = strlen(event_name);
633 hash = jhash(event_name, name_len, 0);
634 head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
d216ecae 635 lttng_hlist_for_each_entry(event, head, hlist) {
3c997079
MD		 636 WARN_ON_ONCE(!event->desc);
637 if (!strncmp(event->desc->name, event_name,
638 LTTNG_KERNEL_SYM_NAME_LEN - 1)
639 && chan == event->chan) {
640 ret = -EEXIST;
641 goto exist;
abc0446a
MD		 642 }
643 }
3c997079 644
11b5a3c2 645 event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
abc0446a 646 if (!event) {
4cf0bf51 647 ret = -ENOMEM;
4e3c1b9b 648 goto cache_error;
abc0446a 649 }
4e3c1b9b
MD		 650 event->chan = chan;
651 event->filter = filter;
e5382b6d 652 event->id = chan->free_event_id++;
3c997079
MD		 653 event->instrumentation = itype;
654 event->evtype = LTTNG_TYPE_EVENT;
07dfc1d0 655 INIT_LIST_HEAD(&event->bytecode_runtime_head);
3c997079
MD		 656 INIT_LIST_HEAD(&event->enablers_ref_head);
657
658 switch (itype) {
ab2277d6 659 case LTTNG_KERNEL_TRACEPOINT:
3c997079
MD		 660 /* Event will be enabled by enabler sync. */
661 event->enabled = 0;
662 event->registered = 0;
663 event->desc = lttng_event_get(event_name);
abc0446a 664 if (!event->desc) {
4cf0bf51 665 ret = -ENOENT;
d3dbe23c 666 goto register_error;
abc0446a 667 }
3c997079
MD		 668 /* Populate lttng_event structure before event registration. */
669 smp_wmb();
baf20995 670 break;
ab2277d6 671 case LTTNG_KERNEL_KPROBE:
a0493bef
MD		 672 /*
673 * Needs to be explicitly enabled after creation, since
674 * we may want to apply filters.
675 */
676 event->enabled = 0;
3c997079
MD		 677 event->registered = 1;
678 /*
679 * Populate lttng_event structure before event
680 * registration.
681 */
682 smp_wmb();
683 ret = lttng_kprobes_register(event_name,
f17701fb
MD		 684 event_param->u.kprobe.symbol_name,
685 event_param->u.kprobe.offset,
686 event_param->u.kprobe.addr,
687 event);
abc0446a 688 if (ret) {
4cf0bf51 689 ret = -EINVAL;
d6d808f3 690 goto register_error;
abc0446a 691 }
edeb3137
MD		 692 ret = try_module_get(event->desc->owner);
693 WARN_ON_ONCE(!ret);
d6d808f3 694 break;
7371f44c
MD		 695 case LTTNG_KERNEL_KRETPROBE:
696 {
a90917c3 697 struct lttng_event *event_return;
7371f44c
MD		 698
699 /* kretprobe defines 2 events */
a0493bef
MD		 700 /*
701 * Needs to be explicitly enabled after creation, since
702 * we may want to apply filters.
703 */
704 event->enabled = 0;
3c997079 705 event->registered = 1;
7371f44c
MD		 706 event_return =
707 kmem_cache_zalloc(event_cache, GFP_KERNEL);
abc0446a 708 if (!event_return) {
4cf0bf51 709 ret = -ENOMEM;
7371f44c 710 goto register_error;
abc0446a 711 }
7371f44c
MD		 712 event_return->chan = chan;
713 event_return->filter = filter;
714 event_return->id = chan->free_event_id++;
a0493bef 715 event_return->enabled = 0;
3c997079
MD		 716 event_return->registered = 1;
717 event_return->instrumentation = itype;
92cc3e7f
FD		 718 INIT_LIST_HEAD(&event_return->bytecode_runtime_head);
719 INIT_LIST_HEAD(&event_return->enablers_ref_head);
7371f44c 720 /*
a90917c3 721 * Populate lttng_event structure before kretprobe registration.
7371f44c
MD		 722 */
723 smp_wmb();
3c997079 724 ret = lttng_kretprobes_register(event_name,
7371f44c
MD		 725 event_param->u.kretprobe.symbol_name,
726 event_param->u.kretprobe.offset,
727 event_param->u.kretprobe.addr,
728 event, event_return);
729 if (ret) {
730 kmem_cache_free(event_cache, event_return);
4cf0bf51 731 ret = -EINVAL;
7371f44c
MD		 732 goto register_error;
733 }
734 /* Take 2 refs on the module: one per event. */
735 ret = try_module_get(event->desc->owner);
736 WARN_ON_ONCE(!ret);
737 ret = try_module_get(event->desc->owner);
738 WARN_ON_ONCE(!ret);
a90917c3 739 ret = _lttng_event_metadata_statedump(chan->session, chan,
7371f44c 740 event_return);
abc0446a 741 WARN_ON_ONCE(ret > 0);
7371f44c
MD		 742 if (ret) {
743 kmem_cache_free(event_cache, event_return);
744 module_put(event->desc->owner);
745 module_put(event->desc->owner);
746 goto statedump_error;
747 }
748 list_add(&event_return->list, &chan->session->events);
749 break;
750 }
1ec65de1 751 case LTTNG_KERNEL_NOOP:
33a39a3c 752 case LTTNG_KERNEL_SYSCALL:
a0493bef
MD		 753 /*
754 * Needs to be explicitly enabled after creation, since
755 * we may want to apply filters.
756 */
757 event->enabled = 0;
3c997079
MD		 758 event->registered = 0;
759 event->desc = event_desc;
ad594e3a
MD		 760 switch (event_param->u.syscall.entryexit) {
761 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
762 ret = -EINVAL;
763 goto register_error;
764 case LTTNG_KERNEL_SYSCALL_ENTRY:
765 event->u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
766 break;
767 case LTTNG_KERNEL_SYSCALL_EXIT:
768 event->u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
769 break;
770 }
771 switch (event_param->u.syscall.abi) {
772 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
773 ret = -EINVAL;
774 goto register_error;
775 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE:
776 event->u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
777 break;
778 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT:
779 event->u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
780 break;
781 }
abc0446a 782 if (!event->desc) {
4cf0bf51 783 ret = -EINVAL;
259b6cb3 784 goto register_error;
abc0446a 785 }
1ec65de1 786 break;
149b9a9d 787 case LTTNG_KERNEL_UPROBE:
a344f64b
FD		 788 /*
789 * Needs to be explicitly enabled after creation, since
790 * we may want to apply filters.
791 */
792 event->enabled = 0;
793 event->registered = 1;
3aed4dca 794
a344f64b
FD		 795 /*
796 * Populate lttng_event structure before event
797 * registration.
798 */
799 smp_wmb();
149b9a9d
YB		 800
801 ret = lttng_uprobes_register(event_param->name,
56377c91 802 event_param->u.uprobe.fd,
149b9a9d
YB		 803 event);
804 if (ret)
805 goto register_error;
806 ret = try_module_get(event->desc->owner);
807 WARN_ON_ONCE(!ret);
808 break;
1d00109f
MJ		 809 case LTTNG_KERNEL_FUNCTION:
810 lttng_fallthrough;
baf20995
MD		 811 default:
812 WARN_ON_ONCE(1);
4cf0bf51 813 ret = -EINVAL;
df07930b 814 goto register_error;
baf20995 815 }
a90917c3 816 ret = _lttng_event_metadata_statedump(chan->session, chan, event);
abc0446a
MD		 817 WARN_ON_ONCE(ret > 0);
818 if (ret) {
c099397a 819 goto statedump_error;
abc0446a 820 }
3c997079 821 hlist_add_head(&event->hlist, head);
dda6a249 822 list_add(&event->list, &chan->session->events);
4e3c1b9b
MD		 823 return event;
824
c099397a 825statedump_error:
259b6cb3 826 /* If a statedump error occurs, events will not be readable. */
11b5a3c2 827register_error:
11b5a3c2 828 kmem_cache_free(event_cache, event);
4e3c1b9b
MD		 829cache_error:
830exist:
3c997079 831type_error:
e5382b6d 832full:
4cf0bf51 833 return ERR_PTR(ret);
4e3c1b9b
MD		 834}
835
3c997079
MD		 836struct lttng_event *lttng_event_create(struct lttng_channel *chan,
837 struct lttng_kernel_event *event_param,
838 void *filter,
839 const struct lttng_event_desc *event_desc,
840 enum lttng_kernel_instrumentation itype)
841{
842 struct lttng_event *event;
843
844 mutex_lock(&sessions_mutex);
845 event = _lttng_event_create(chan, event_param, filter, event_desc,
846 itype);
847 mutex_unlock(&sessions_mutex);
848 return event;
849}
850
851/* Only used for tracepoints for now. */
852static
853void register_event(struct lttng_event *event)
854{
855 const struct lttng_event_desc *desc;
f127e61e 856 int ret = -EINVAL;
3c997079 857
3c997079
MD		 858 if (event->registered)
859 return;
4ecb5ad5 860
3c997079 861 desc = event->desc;
4ecb5ad5
MD		 862 switch (event->instrumentation) {
863 case LTTNG_KERNEL_TRACEPOINT:
864 ret = lttng_wrapper_tracepoint_probe_register(desc->kname,
865 desc->probe_callback,
866 event);
867 break;
868 case LTTNG_KERNEL_SYSCALL:
ad594e3a 869 ret = lttng_syscall_filter_enable(event->chan, event);
4ecb5ad5
MD		 870 break;
871 case LTTNG_KERNEL_KPROBE:
a344f64b 872 case LTTNG_KERNEL_UPROBE:
4ecb5ad5 873 case LTTNG_KERNEL_KRETPROBE:
4ecb5ad5
MD		 874 case LTTNG_KERNEL_NOOP:
875 ret = 0;
876 break;
1d00109f
MJ		 877 case LTTNG_KERNEL_FUNCTION:
878 lttng_fallthrough;
4ecb5ad5
MD		 879 default:
880 WARN_ON_ONCE(1);
881 }
3c997079
MD		 882 if (!ret)
883 event->registered = 1;
884}
885
4e3c1b9b
MD		 886/*
887 * Only used internally at session destruction.
888 */
a90917c3 889int _lttng_event_unregister(struct lttng_event *event)
4e3c1b9b 890{
4ecb5ad5 891 const struct lttng_event_desc *desc;
11b5a3c2
MD		 892 int ret = -EINVAL;
893
3c997079
MD		 894 if (!event->registered)
895 return 0;
896
4ecb5ad5 897 desc = event->desc;
38d024ae 898 switch (event->instrumentation) {
ab2277d6 899 case LTTNG_KERNEL_TRACEPOINT:
20591cf7 900 ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname,
85a9ca7f 901 event->desc->probe_callback,
11b5a3c2 902 event);
baf20995 903 break;
ab2277d6 904 case LTTNG_KERNEL_KPROBE:
f17701fb 905 lttng_kprobes_unregister(event);
d6d808f3
MD		 906 ret = 0;
907 break;
7371f44c
MD		 908 case LTTNG_KERNEL_KRETPROBE:
909 lttng_kretprobes_unregister(event);
910 ret = 0;
911 break;
33a39a3c 912 case LTTNG_KERNEL_SYSCALL:
ad594e3a 913 ret = lttng_syscall_filter_disable(event->chan, event);
4ecb5ad5
MD		 914 break;
915 case LTTNG_KERNEL_NOOP:
259b6cb3
MD		 916 ret = 0;
917 break;
149b9a9d
YB		 918 case LTTNG_KERNEL_UPROBE:
919 lttng_uprobes_unregister(event);
920 ret = 0;
921 break;
1d00109f
MJ		 922 case LTTNG_KERNEL_FUNCTION:
923 lttng_fallthrough;
baf20995
MD		 924 default:
925 WARN_ON_ONCE(1);
926 }
3c997079
MD		 927 if (!ret)
928 event->registered = 0;
dda6a249
MD		 929 return ret;
930}
931
932/*
933 * Only used internally at session destruction.
934 */
be066e6c 935static
a90917c3 936void _lttng_event_destroy(struct lttng_event *event)
dda6a249 937{
b3fdf78b
MD		 938 struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref;
939
edeb3137
MD		 940 switch (event->instrumentation) {
941 case LTTNG_KERNEL_TRACEPOINT:
a90917c3 942 lttng_event_put(event->desc);
edeb3137
MD		 943 break;
944 case LTTNG_KERNEL_KPROBE:
945 module_put(event->desc->owner);
946 lttng_kprobes_destroy_private(event);
947 break;
7371f44c
MD		 948 case LTTNG_KERNEL_KRETPROBE:
949 module_put(event->desc->owner);
950 lttng_kretprobes_destroy_private(event);
951 break;
259b6cb3 952 case LTTNG_KERNEL_NOOP:
33a39a3c 953 case LTTNG_KERNEL_SYSCALL:
259b6cb3 954 break;
149b9a9d
YB		 955 case LTTNG_KERNEL_UPROBE:
956 module_put(event->desc->owner);
957 lttng_uprobes_destroy_private(event);
958 break;
1d00109f
MJ		 959 case LTTNG_KERNEL_FUNCTION:
960 lttng_fallthrough;
edeb3137
MD		 961 default:
962 WARN_ON_ONCE(1);
963 }
dda6a249 964 list_del(&event->list);
8070f5c0 965 lttng_destroy_context(event->ctx);
b3fdf78b
MD		 966 lttng_free_event_filter_runtime(event);
967 /* Free event enabler refs */
968 list_for_each_entry_safe(enabler_ref, tmp_enabler_ref,
969 &event->enablers_ref_head, node)
970 kfree(enabler_ref);
11b5a3c2 971 kmem_cache_free(event_cache, event);
4e3c1b9b
MD		 972}
973
d1f652f8
MD		 974struct lttng_id_tracker *get_tracker(struct lttng_session *session,
975 enum tracker_type tracker_type)
e0130fab 976{
d1f652f8
MD		 977 switch (tracker_type) {
978 case TRACKER_PID:
979 return &session->pid_tracker;
980 case TRACKER_VPID:
981 return &session->vpid_tracker;
982 case TRACKER_UID:
983 return &session->uid_tracker;
984 case TRACKER_VUID:
985 return &session->vuid_tracker;
986 case TRACKER_GID:
987 return &session->gid_tracker;
988 case TRACKER_VGID:
989 return &session->vgid_tracker;
990 default:
991 WARN_ON_ONCE(1);
992 return NULL;
993 }
994}
995
996int lttng_session_track_id(struct lttng_session *session,
997 enum tracker_type tracker_type, int id)
998{
999 struct lttng_id_tracker *tracker;
e0130fab
MD		 1000 int ret;
1001
d1f652f8
MD		 1002 tracker = get_tracker(session, tracker_type);
1003 if (!tracker)
1004 return -EINVAL;
1005 if (id < -1)
e0130fab
MD		 1006 return -EINVAL;
1007 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1008 if (id == -1) {
1009 /* track all ids: destroy tracker. */
1010 lttng_id_tracker_destroy(tracker, true);
e0130fab
MD		 1011 ret = 0;
1012 } else {
d1f652f8 1013 ret = lttng_id_tracker_add(tracker, id);
e0130fab 1014 }
e0130fab
MD		 1015 mutex_unlock(&sessions_mutex);
1016 return ret;
1017}
1018
d1f652f8
MD		 1019int lttng_session_untrack_id(struct lttng_session *session,
1020 enum tracker_type tracker_type, int id)
e0130fab 1021{
d1f652f8 1022 struct lttng_id_tracker *tracker;
e0130fab
MD		 1023 int ret;
1024
d1f652f8
MD		 1025 tracker = get_tracker(session, tracker_type);
1026 if (!tracker)
1027 return -EINVAL;
1028 if (id < -1)
e0130fab
MD		 1029 return -EINVAL;
1030 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1031 if (id == -1) {
1032 /* untrack all ids: replace by empty tracker. */
1033 ret = lttng_id_tracker_empty_set(tracker);
e0130fab 1034 } else {
d1f652f8 1035 ret = lttng_id_tracker_del(tracker, id);
e0130fab 1036 }
e0130fab
MD		 1037 mutex_unlock(&sessions_mutex);
1038 return ret;
1039}
1040
7e6f9ef6 1041static
d1f652f8 1042void *id_list_start(struct seq_file *m, loff_t *pos)
7e6f9ef6 1043{
d1f652f8
MD		 1044 struct lttng_id_tracker *id_tracker = m->private;
1045 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1046 struct lttng_id_hash_node *e;
7e6f9ef6
MD		 1047 int iter = 0, i;
1048
1049 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1050 if (id_tracker_p) {
1051 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1052 struct hlist_head *head = &id_tracker_p->id_hash[i];
7e6f9ef6 1053
f934e302 1054 lttng_hlist_for_each_entry(e, head, hlist) {
7e6f9ef6
MD		 1055 if (iter++ >= *pos)
1056 return e;
1057 }
1058 }
1059 } else {
d1f652f8 1060 /* ID tracker disabled. */
7e6f9ef6 1061 if (iter >= *pos && iter == 0) {
d1f652f8 1062 return id_tracker_p; /* empty tracker */
7e6f9ef6
MD		 1063 }
1064 iter++;
1065 }
1066 /* End of list */
1067 return NULL;
1068}
1069
1070/* Called with sessions_mutex held. */
1071static
d1f652f8 1072void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
7e6f9ef6 1073{
d1f652f8
MD		 1074 struct lttng_id_tracker *id_tracker = m->private;
1075 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1076 struct lttng_id_hash_node *e;
7e6f9ef6
MD		 1077 int iter = 0, i;
1078
1079 (*ppos)++;
d1f652f8
MD		 1080 if (id_tracker_p) {
1081 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1082 struct hlist_head *head = &id_tracker_p->id_hash[i];
7e6f9ef6 1083
f934e302 1084 lttng_hlist_for_each_entry(e, head, hlist) {
7e6f9ef6
MD		 1085 if (iter++ >= *ppos)
1086 return e;
1087 }
1088 }
1089 } else {
d1f652f8 1090 /* ID tracker disabled. */
7e6f9ef6 1091 if (iter >= *ppos && iter == 0)
d1f652f8 1092 return p; /* empty tracker */
7e6f9ef6
MD		 1093 iter++;
1094 }
1095
1096 /* End of list */
1097 return NULL;
1098}
1099
1100static
d1f652f8 1101void id_list_stop(struct seq_file *m, void *p)
7e6f9ef6
MD		 1102{
1103 mutex_unlock(&sessions_mutex);
1104}
1105
1106static
d1f652f8 1107int id_list_show(struct seq_file *m, void *p)
7e6f9ef6 1108{
d1f652f8
MD		 1109 struct lttng_id_tracker *id_tracker = m->private;
1110 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1111 int id;
7e6f9ef6 1112
d1f652f8 1113 if (p == id_tracker_p) {
7e6f9ef6 1114 /* Tracker disabled. */
d1f652f8 1115 id = -1;
7e6f9ef6 1116 } else {
d1f652f8 1117 const struct lttng_id_hash_node *e = p;
7e6f9ef6 1118
d1f652f8
MD		 1119 id = lttng_id_tracker_get_node_id(e);
1120 }
1121 switch (id_tracker->tracker_type) {
1122 case TRACKER_PID:
1123 seq_printf(m, "process { pid = %d; };\n", id);
1124 break;
1125 case TRACKER_VPID:
1126 seq_printf(m, "process { vpid = %d; };\n", id);
1127 break;
1128 case TRACKER_UID:
1129 seq_printf(m, "user { uid = %d; };\n", id);
1130 break;
1131 case TRACKER_VUID:
1132 seq_printf(m, "user { vuid = %d; };\n", id);
1133 break;
1134 case TRACKER_GID:
1135 seq_printf(m, "group { gid = %d; };\n", id);
1136 break;
1137 case TRACKER_VGID:
1138 seq_printf(m, "group { vgid = %d; };\n", id);
1139 break;
1140 default:
1141 seq_printf(m, "UNKNOWN { field = %d };\n", id);
7e6f9ef6 1142 }
7e6f9ef6
MD		 1143 return 0;
1144}
1145
1146static
d1f652f8
MD		 1147const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1148 .start = id_list_start,
1149 .next = id_list_next,
1150 .stop = id_list_stop,
1151 .show = id_list_show,
7e6f9ef6
MD		 1152};
1153
1154static
d1f652f8 1155int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
7e6f9ef6 1156{
d1f652f8 1157 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
7e6f9ef6
MD		 1158}
1159
1160static
d1f652f8 1161int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
7e6f9ef6
MD		 1162{
1163 struct seq_file *m = file->private_data;
d1f652f8 1164 struct lttng_id_tracker *id_tracker = m->private;
7e6f9ef6
MD		 1165 int ret;
1166
d1f652f8 1167 WARN_ON_ONCE(!id_tracker);
7e6f9ef6 1168 ret = seq_release(inode, file);
d1f652f8
MD		 1169 if (!ret)
1170 fput(id_tracker->session->file);
7e6f9ef6
MD		 1171 return ret;
1172}
1173
d1f652f8 1174const struct file_operations lttng_tracker_ids_list_fops = {
7e6f9ef6 1175 .owner = THIS_MODULE,
d1f652f8 1176 .open = lttng_tracker_ids_list_open,
7e6f9ef6
MD		 1177 .read = seq_read,
1178 .llseek = seq_lseek,
d1f652f8 1179 .release = lttng_tracker_ids_list_release,
7e6f9ef6
MD		 1180};
1181
d1f652f8
MD		 1182int lttng_session_list_tracker_ids(struct lttng_session *session,
1183 enum tracker_type tracker_type)
7e6f9ef6 1184{
d1f652f8 1185 struct file *tracker_ids_list_file;
7e6f9ef6
MD		 1186 struct seq_file *m;
1187 int file_fd, ret;
1188
1189 file_fd = lttng_get_unused_fd();
1190 if (file_fd < 0) {
1191 ret = file_fd;
1192 goto fd_error;
1193 }
1194
d1f652f8
MD		 1195 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1196 &lttng_tracker_ids_list_fops,
7e6f9ef6 1197 NULL, O_RDWR);
d1f652f8
MD		 1198 if (IS_ERR(tracker_ids_list_file)) {
1199 ret = PTR_ERR(tracker_ids_list_file);
7e6f9ef6
MD		 1200 goto file_error;
1201 }
98d7281c
MJ		 1202 if (!atomic_long_add_unless(&session->file->f_count, 1, LONG_MAX)) {
1203 ret = -EOVERFLOW;
9c1f4643
MD		 1204 goto refcount_error;
1205 }
d1f652f8 1206 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
7e6f9ef6
MD		 1207 if (ret < 0)
1208 goto open_error;
d1f652f8
MD		 1209 m = tracker_ids_list_file->private_data;
1210
1211 m->private = get_tracker(session, tracker_type);
1212 BUG_ON(!m->private);
1213 fd_install(file_fd, tracker_ids_list_file);
7e6f9ef6
MD		 1214
1215 return file_fd;
1216
1217open_error:
9c1f4643
MD		 1218 atomic_long_dec(&session->file->f_count);
1219refcount_error:
d1f652f8 1220 fput(tracker_ids_list_file);
7e6f9ef6
MD		 1221file_error:
1222 put_unused_fd(file_fd);
1223fd_error:
1224 return ret;
1225}
1226
3c997079
MD		 1227/*
1228 * Enabler management.
1229 */
1230static
4993071a
PP		 1231int lttng_match_enabler_star_glob(const char *desc_name,
1232 const char *pattern)
3c997079 1233{
cbc19040
MD		 1234 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1235 desc_name, LTTNG_SIZE_MAX))
3c997079
MD		 1236 return 0;
1237 return 1;
1238}
1239
1240static
4ecb5ad5
MD		 1241int lttng_match_enabler_name(const char *desc_name,
1242 const char *name)
3c997079 1243{
4ecb5ad5 1244 if (strcmp(desc_name, name))
3c997079
MD		 1245 return 0;
1246 return 1;
1247}
1248
1249static
1250int lttng_desc_match_enabler(const struct lttng_event_desc *desc,
1251 struct lttng_enabler *enabler)
1252{
4ecb5ad5 1253 const char *desc_name, *enabler_name;
ad594e3a 1254 bool compat = false, entry = false;
4ecb5ad5
MD		 1255
1256 enabler_name = enabler->event_param.name;
1257 switch (enabler->event_param.instrumentation) {
1258 case LTTNG_KERNEL_TRACEPOINT:
1259 desc_name = desc->name;
ad594e3a
MD		 1260 switch (enabler->type) {
1261 case LTTNG_ENABLER_STAR_GLOB:
1262 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1263 case LTTNG_ENABLER_NAME:
1264 return lttng_match_enabler_name(desc_name, enabler_name);
1265 default:
1266 return -EINVAL;
1267 }
4ecb5ad5
MD		 1268 break;
1269 case LTTNG_KERNEL_SYSCALL:
1270 desc_name = desc->name;
ad594e3a 1271 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
4ecb5ad5 1272 desc_name += strlen("compat_");
ad594e3a
MD		 1273 compat = true;
1274 }
4ecb5ad5
MD		 1275 if (!strncmp(desc_name, "syscall_exit_",
1276 strlen("syscall_exit_"))) {
1277 desc_name += strlen("syscall_exit_");
1278 } else if (!strncmp(desc_name, "syscall_entry_",
1279 strlen("syscall_entry_"))) {
1280 desc_name += strlen("syscall_entry_");
ad594e3a 1281 entry = true;
4ecb5ad5
MD		 1282 } else {
1283 WARN_ON_ONCE(1);
1284 return -EINVAL;
1285 }
ad594e3a
MD		 1286 switch (enabler->event_param.u.syscall.entryexit) {
1287 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
1288 break;
1289 case LTTNG_KERNEL_SYSCALL_ENTRY:
1290 if (!entry)
1291 return 0;
1292 break;
1293 case LTTNG_KERNEL_SYSCALL_EXIT:
1294 if (entry)
1295 return 0;
1296 break;
1297 default:
1298 return -EINVAL;
1299 }
1300 switch (enabler->event_param.u.syscall.abi) {
1301 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
1302 break;
1303 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE:
1304 if (compat)
1305 return 0;
1306 break;
1307 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT:
1308 if (!compat)
1309 return 0;
1310 break;
1311 default:
1312 return -EINVAL;
1313 }
1314 switch (enabler->event_param.u.syscall.match) {
1315 case LTTNG_SYSCALL_MATCH_NAME:
1316 switch (enabler->type) {
1317 case LTTNG_ENABLER_STAR_GLOB:
1318 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1319 case LTTNG_ENABLER_NAME:
1320 return lttng_match_enabler_name(desc_name, enabler_name);
1321 default:
1322 return -EINVAL;
1323 }
1324 break;
1325 case LTTNG_SYSCALL_MATCH_NR:
1326 return -EINVAL; /* Not implemented. */
1327 default:
1328 return -EINVAL;
1329 }
4ecb5ad5
MD		 1330 break;
1331 default:
1332 WARN_ON_ONCE(1);
1333 return -EINVAL;
1334 }
3c997079
MD		 1335}
1336
1337static
1338int lttng_event_match_enabler(struct lttng_event *event,
1339 struct lttng_enabler *enabler)
1340{
33a39a3c
MD		 1341 if (enabler->event_param.instrumentation != event->instrumentation)
1342 return 0;
3c997079
MD		 1343 if (lttng_desc_match_enabler(event->desc, enabler)
1344 && event->chan == enabler->chan)
1345 return 1;
1346 else
1347 return 0;
1348}
1349
1350static
1351struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event,
1352 struct lttng_enabler *enabler)
1353{
1354 struct lttng_enabler_ref *enabler_ref;
1355
1356 list_for_each_entry(enabler_ref,
1357 &event->enablers_ref_head, node) {
1358 if (enabler_ref->ref == enabler)
1359 return enabler_ref;
1360 }
1361 return NULL;
1362}
1363
3c997079 1364static
33a39a3c 1365void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler)
3c997079
MD		 1366{
1367 struct lttng_session *session = enabler->chan->session;
1368 struct lttng_probe_desc *probe_desc;
1369 const struct lttng_event_desc *desc;
1370 int i;
1371 struct list_head *probe_list;
1372
1373 probe_list = lttng_get_probe_list_head();
1374 /*
1375 * For each probe event, if we find that a probe event matches
1376 * our enabler, create an associated lttng_event if not
1377 * already present.
1378 */
1379 list_for_each_entry(probe_desc, probe_list, head) {
1380 for (i = 0; i < probe_desc->nr_events; i++) {
1381 int found = 0;
1382 struct hlist_head *head;
1383 const char *event_name;
1384 size_t name_len;
1385 uint32_t hash;
1386 struct lttng_event *event;
1387
1388 desc = probe_desc->event_desc[i];
1389 if (!lttng_desc_match_enabler(desc, enabler))
1390 continue;
1391 event_name = desc->name;
1392 name_len = strlen(event_name);
1393
1394 /*
1395 * Check if already created.
1396 */
1397 hash = jhash(event_name, name_len, 0);
1398 head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)];
d216ecae 1399 lttng_hlist_for_each_entry(event, head, hlist) {
3c997079
MD		 1400 if (event->desc == desc
1401 && event->chan == enabler->chan)
1402 found = 1;
1403 }
1404 if (found)
1405 continue;
1406
1407 /*
1408 * We need to create an event for this
1409 * event probe.
1410 */
1411 event = _lttng_event_create(enabler->chan,
1412 NULL, NULL, desc,
1413 LTTNG_KERNEL_TRACEPOINT);
1414 if (!event) {
1415 printk(KERN_INFO "Unable to create event %s\n",
1416 probe_desc->event_desc[i]->name);
1417 }
1418 }
1419 }
1420}
1421
33a39a3c
MD		 1422static
1423void lttng_create_syscall_if_missing(struct lttng_enabler *enabler)
1424{
1425 int ret;
1426
1427 ret = lttng_syscalls_register(enabler->chan, NULL);
1428 WARN_ON_ONCE(ret);
1429}
1430
1431/*
1432 * Create struct lttng_event if it is missing and present in the list of
1433 * tracepoint probes.
1434 * Should be called with sessions mutex held.
1435 */
1436static
1437void lttng_create_event_if_missing(struct lttng_enabler *enabler)
1438{
1439 switch (enabler->event_param.instrumentation) {
1440 case LTTNG_KERNEL_TRACEPOINT:
1441 lttng_create_tracepoint_if_missing(enabler);
1442 break;
1443 case LTTNG_KERNEL_SYSCALL:
1444 lttng_create_syscall_if_missing(enabler);
1445 break;
1446 default:
1447 WARN_ON_ONCE(1);
1448 break;
1449 }
1450}
1451
3c997079
MD		 1452/*
1453 * Create events associated with an enabler (if not already present),
1454 * and add backward reference from the event to the enabler.
1455 * Should be called with sessions mutex held.
1456 */
1457static
1458int lttng_enabler_ref_events(struct lttng_enabler *enabler)
1459{
ad594e3a
MD		 1460 struct lttng_channel *chan = enabler->chan;
1461 struct lttng_session *session = chan->session;
3c997079
MD		 1462 struct lttng_event *event;
1463
ad594e3a
MD		 1464 if (enabler->event_param.instrumentation == LTTNG_KERNEL_SYSCALL &&
1465 enabler->event_param.u.syscall.entryexit == LTTNG_KERNEL_SYSCALL_ENTRYEXIT &&
1466 enabler->event_param.u.syscall.abi == LTTNG_KERNEL_SYSCALL_ABI_ALL &&
1467 enabler->event_param.u.syscall.match == LTTNG_SYSCALL_MATCH_NAME &&
1468 !strcmp(enabler->event_param.name, "*")) {
1469 if (enabler->enabled)
1470 WRITE_ONCE(chan->syscall_all, 1);
1471 else
1472 WRITE_ONCE(chan->syscall_all, 0);
1473 }
1474
3c997079
MD		 1475 /* First ensure that probe events are created for this enabler. */
1476 lttng_create_event_if_missing(enabler);
1477
1478 /* For each event matching enabler in session event list. */
1479 list_for_each_entry(event, &session->events, list) {
1480 struct lttng_enabler_ref *enabler_ref;
1481
1482 if (!lttng_event_match_enabler(event, enabler))
1483 continue;
1484 enabler_ref = lttng_event_enabler_ref(event, enabler);
1485 if (!enabler_ref) {
1486 /*
1487 * If no backward ref, create it.
1488 * Add backward ref from event to enabler.
1489 */
1490 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
1491 if (!enabler_ref)
1492 return -ENOMEM;
1493 enabler_ref->ref = enabler;
1494 list_add(&enabler_ref->node,
1495 &event->enablers_ref_head);
1496 }
1497
f127e61e
MD		 1498 /*
1499 * Link filter bytecodes if not linked yet.
1500 */
1501 lttng_enabler_event_link_bytecode(event, enabler);
1502
3c997079
MD		 1503 /* TODO: merge event context. */
1504 }
1505 return 0;
1506}
1507
1508/*
1509 * Called at module load: connect the probe on all enablers matching
1510 * this event.
1511 * Called with sessions lock held.
1512 */
1513int lttng_fix_pending_events(void)
1514{
1515 struct lttng_session *session;
1516
1517 list_for_each_entry(session, &sessions, list)
1518 lttng_session_lazy_sync_enablers(session);
1519 return 0;
1520}
1521
1522struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type,
1523 struct lttng_kernel_event *event_param,
1524 struct lttng_channel *chan)
1525{
1526 struct lttng_enabler *enabler;
1527
1528 enabler = kzalloc(sizeof(*enabler), GFP_KERNEL);
1529 if (!enabler)
1530 return NULL;
1531 enabler->type = type;
07dfc1d0 1532 INIT_LIST_HEAD(&enabler->filter_bytecode_head);
3c997079
MD		 1533 memcpy(&enabler->event_param, event_param,
1534 sizeof(enabler->event_param));
1535 enabler->chan = chan;
1536 /* ctx left NULL */
4fd19d8a 1537 enabler->enabled = 0;
3c997079
MD		 1538 enabler->evtype = LTTNG_TYPE_ENABLER;
1539 mutex_lock(&sessions_mutex);
1540 list_add(&enabler->node, &enabler->chan->session->enablers_head);
1541 lttng_session_lazy_sync_enablers(enabler->chan->session);
1542 mutex_unlock(&sessions_mutex);
1543 return enabler;
1544}
1545
1546int lttng_enabler_enable(struct lttng_enabler *enabler)
1547{
1548 mutex_lock(&sessions_mutex);
1549 enabler->enabled = 1;
1550 lttng_session_lazy_sync_enablers(enabler->chan->session);
1551 mutex_unlock(&sessions_mutex);
1552 return 0;
1553}
1554
1555int lttng_enabler_disable(struct lttng_enabler *enabler)
1556{
1557 mutex_lock(&sessions_mutex);
1558 enabler->enabled = 0;
1559 lttng_session_lazy_sync_enablers(enabler->chan->session);
1560 mutex_unlock(&sessions_mutex);
1561 return 0;
1562}
1563
07dfc1d0
MD		 1564int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
1565 struct lttng_kernel_filter_bytecode __user *bytecode)
1566{
1567 struct lttng_filter_bytecode_node *bytecode_node;
1568 uint32_t bytecode_len;
1569 int ret;
1570
1571 ret = get_user(bytecode_len, &bytecode->len);
1572 if (ret)
1573 return ret;
1574 bytecode_node = kzalloc(sizeof(*bytecode_node) + bytecode_len,
1575 GFP_KERNEL);
1576 if (!bytecode_node)
1577 return -ENOMEM;
1578 ret = copy_from_user(&bytecode_node->bc, bytecode,
1579 sizeof(*bytecode) + bytecode_len);
1580 if (ret)
1581 goto error_free;
1582 bytecode_node->enabler = enabler;
1583 /* Enforce length based on allocated size */
1584 bytecode_node->bc.len = bytecode_len;
1585 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
1586 lttng_session_lazy_sync_enablers(enabler->chan->session);
1587 return 0;
1588
1589error_free:
1590 kfree(bytecode_node);
1591 return ret;
1592}
1593
3aed4dca
FD		 1594int lttng_event_add_callsite(struct lttng_event *event,
1595 struct lttng_kernel_event_callsite __user *callsite)
1596{
1597
1598 switch (event->instrumentation) {
1599 case LTTNG_KERNEL_UPROBE:
1600 return lttng_uprobes_add_callsite(event, callsite);
1601 default:
1602 return -EINVAL;
1603 }
1604}
1605
3c997079
MD		 1606int lttng_enabler_attach_context(struct lttng_enabler *enabler,
1607 struct lttng_kernel_context *context_param)
1608{
1609 return -ENOSYS;
1610}
1611
1612static
1613void lttng_enabler_destroy(struct lttng_enabler *enabler)
1614{
07dfc1d0
MD		 1615 struct lttng_filter_bytecode_node *filter_node, *tmp_filter_node;
1616
1617 /* Destroy filter bytecode */
1618 list_for_each_entry_safe(filter_node, tmp_filter_node,
1619 &enabler->filter_bytecode_head, node) {
1620 kfree(filter_node);
1621 }
1622
3c997079
MD		 1623 /* Destroy contexts */
1624 lttng_destroy_context(enabler->ctx);
1625
1626 list_del(&enabler->node);
1627 kfree(enabler);
1628}
1629
1630/*
1631 * lttng_session_sync_enablers should be called just before starting a
1632 * session.
1633 * Should be called with sessions mutex held.
1634 */
1635static
1636void lttng_session_sync_enablers(struct lttng_session *session)
1637{
1638 struct lttng_enabler *enabler;
1639 struct lttng_event *event;
1640
1641 list_for_each_entry(enabler, &session->enablers_head, node)
1642 lttng_enabler_ref_events(enabler);
1643 /*
1644 * For each event, if at least one of its enablers is enabled,
1645 * and its channel and session transient states are enabled, we
1646 * enable the event, else we disable it.
1647 */
1648 list_for_each_entry(event, &session->events, list) {
1649 struct lttng_enabler_ref *enabler_ref;
07dfc1d0
MD		 1650 struct lttng_bytecode_runtime *runtime;
1651 int enabled = 0, has_enablers_without_bytecode = 0;
3c997079 1652
4ecb5ad5
MD		 1653 switch (event->instrumentation) {
1654 case LTTNG_KERNEL_TRACEPOINT:
1655 case LTTNG_KERNEL_SYSCALL:
3c997079
MD		 1656 /* Enable events */
1657 list_for_each_entry(enabler_ref,
1658 &event->enablers_ref_head, node) {
1659 if (enabler_ref->ref->enabled) {
1660 enabled = 1;
1661 break;
1662 }
1663 }
4ecb5ad5
MD		 1664 break;
1665 default:
3c997079
MD		 1666 /* Not handled with lazy sync. */
1667 continue;
1668 }
1669 /*
1670 * Enabled state is based on union of enablers, with
1671 * intesection of session and channel transient enable
1672 * states.
1673 */
1674 enabled = enabled && session->tstate && event->chan->tstate;
1675
a8f2d0c7 1676 WRITE_ONCE(event->enabled, enabled);
3c997079
MD		 1677 /*
1678 * Sync tracepoint registration with event enabled
1679 * state.
1680 */
1681 if (enabled) {
1682 register_event(event);
1683 } else {
1684 _lttng_event_unregister(event);
1685 }
07dfc1d0
MD		 1686
1687 /* Check if has enablers without bytecode enabled */
1688 list_for_each_entry(enabler_ref,
1689 &event->enablers_ref_head, node) {
1690 if (enabler_ref->ref->enabled
1691 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
1692 has_enablers_without_bytecode = 1;
1693 break;
1694 }
1695 }
1696 event->has_enablers_without_bytecode =
1697 has_enablers_without_bytecode;
1698
1699 /* Enable filters */
1700 list_for_each_entry(runtime,
f127e61e 1701 &event->bytecode_runtime_head, node)
07dfc1d0 1702 lttng_filter_sync_state(runtime);
3c997079
MD		 1703 }
1704}
1705
1706/*
1707 * Apply enablers to session events, adding events to session if need
1708 * be. It is required after each modification applied to an active
1709 * session, and right before session "start".
1710 * "lazy" sync means we only sync if required.
1711 * Should be called with sessions mutex held.
1712 */
1713static
1714void lttng_session_lazy_sync_enablers(struct lttng_session *session)
1715{
1716 /* We can skip if session is not active */
1717 if (!session->active)
1718 return;
1719 lttng_session_sync_enablers(session);
1720}
1721
1ec3f75a 1722/*
d83004aa
JD		 1723 * Serialize at most one packet worth of metadata into a metadata
1724 * channel.
92d9f5e6
MD		 1725 * We grab the metadata cache mutex to get exclusive access to our metadata
1726 * buffer and to the metadata cache. Exclusive access to the metadata buffer
1727 * allows us to do racy operations such as looking for remaining space left in
1728 * packet and write, since mutual exclusion protects us from concurrent writes.
1729 * Mutual exclusion on the metadata cache allow us to read the cache content
1730 * without racing against reallocation of the cache by updates.
35097f36
JD		 1731 * Returns the number of bytes written in the channel, 0 if no data
1732 * was written and a negative value on error.
1ec3f75a 1733 */
b3b8072b 1734int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
122c63cb 1735 struct channel *chan, bool *coherent)
d83004aa
JD		 1736{
1737 struct lib_ring_buffer_ctx ctx;
1738 int ret = 0;
1739 size_t len, reserve_len;
1740
f613e3e6 1741 /*
92d9f5e6
MD		 1742 * Ensure we support mutiple get_next / put sequences followed by
1743 * put_next. The metadata cache lock protects reading the metadata
1744 * cache. It can indeed be read concurrently by "get_next_subbuf" and
1745 * "flush" operations on the buffer invoked by different processes.
1746 * Moreover, since the metadata cache memory can be reallocated, we
1747 * need to have exclusive access against updates even though we only
1748 * read it.
f613e3e6 1749 */
92d9f5e6 1750 mutex_lock(&stream->metadata_cache->lock);
f613e3e6
MD		 1751 WARN_ON(stream->metadata_in < stream->metadata_out);
1752 if (stream->metadata_in != stream->metadata_out)
de23d59d 1753 goto end;
f613e3e6 1754
9616f0bf
JD		 1755 /* Metadata regenerated, change the version. */
1756 if (stream->metadata_cache->version != stream->version)
1757 stream->version = stream->metadata_cache->version;
1758
d83004aa 1759 len = stream->metadata_cache->metadata_written -
f613e3e6 1760 stream->metadata_in;
9de2c215 1761 if (!len)
de23d59d 1762 goto end;
d83004aa 1763 reserve_len = min_t(size_t,
b3b8072b 1764 stream->transport->ops.packet_avail_size(chan),
d83004aa 1765 len);
b3b8072b 1766 lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len,
d83004aa
JD		 1767 sizeof(char), -1);
1768 /*
1769 * If reservation failed, return an error to the caller.
1770 */
b3b8072b 1771 ret = stream->transport->ops.event_reserve(&ctx, 0);
d83004aa
JD		 1772 if (ret != 0) {
1773 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
122c63cb 1774 stream->coherent = false;
d83004aa
JD		 1775 goto end;
1776 }
b3b8072b 1777 stream->transport->ops.event_write(&ctx,
f613e3e6 1778 stream->metadata_cache->data + stream->metadata_in,
d83004aa 1779 reserve_len);
b3b8072b 1780 stream->transport->ops.event_commit(&ctx);
f613e3e6 1781 stream->metadata_in += reserve_len;
3780dda9 1782 if (reserve_len < len)
122c63cb
MD		 1783 stream->coherent = false;
1784 else
1785 stream->coherent = true;
d83004aa
JD		 1786 ret = reserve_len;
1787
1788end:
122c63cb
MD		 1789 if (coherent)
1790 *coherent = stream->coherent;
92d9f5e6 1791 mutex_unlock(&stream->metadata_cache->lock);
d83004aa
JD		 1792 return ret;
1793}
1794
122c63cb
MD		 1795static
1796void lttng_metadata_begin(struct lttng_session *session)
1797{
3780dda9
MD		 1798 if (atomic_inc_return(&session->metadata_cache->producing) == 1)
1799 mutex_lock(&session->metadata_cache->lock);
122c63cb
MD		 1800}
1801
1802static
1803void lttng_metadata_end(struct lttng_session *session)
1804{
3780dda9
MD		 1805 WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
1806 if (atomic_dec_return(&session->metadata_cache->producing) == 0) {
1807 struct lttng_metadata_stream *stream;
1808
3780dda9
MD		 1809 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
1810 wake_up_interruptible(&stream->read_wait);
e0d82ce5 1811 mutex_unlock(&session->metadata_cache->lock);
3780dda9 1812 }
122c63cb
MD		 1813}
1814
d83004aa
JD		 1815/*
1816 * Write the metadata to the metadata cache.
1817 * Must be called with sessions_mutex held.
92d9f5e6
MD		 1818 * The metadata cache lock protects us from concurrent read access from
1819 * thread outputting metadata content to ring buffer.
122c63cb
MD		 1820 * The content of the printf is printed as a single atomic metadata
1821 * transaction.
d83004aa 1822 */
a90917c3 1823int lttng_metadata_printf(struct lttng_session *session,
c099397a
MD		 1824 const char *fmt, ...)
1825{
c099397a 1826 char *str;
d83004aa 1827 size_t len;
c099397a
MD		 1828 va_list ap;
1829
57ccbfa6 1830 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
c099397a
MD		 1831
1832 va_start(ap, fmt);
1833 str = kvasprintf(GFP_KERNEL, fmt, ap);
1834 va_end(ap);
1835 if (!str)
1836 return -ENOMEM;
1837
1ec3f75a 1838 len = strlen(str);
3780dda9 1839 WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
d83004aa
JD		 1840 if (session->metadata_cache->metadata_written + len >
1841 session->metadata_cache->cache_alloc) {
1842 char *tmp_cache_realloc;
1843 unsigned int tmp_cache_alloc_size;
1844
1845 tmp_cache_alloc_size = max_t(unsigned int,
1846 session->metadata_cache->cache_alloc + len,
1847 session->metadata_cache->cache_alloc << 1);
0ca42eb7 1848 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
d83004aa
JD		 1849 if (!tmp_cache_realloc)
1850 goto err;
a606b6e8
ML		 1851 if (session->metadata_cache->data) {
1852 memcpy(tmp_cache_realloc,
1853 session->metadata_cache->data,
1854 session->metadata_cache->cache_alloc);
1855 vfree(session->metadata_cache->data);
1856 }
1857
d83004aa
JD		 1858 session->metadata_cache->cache_alloc = tmp_cache_alloc_size;
1859 session->metadata_cache->data = tmp_cache_realloc;
c099397a 1860 }
d83004aa
JD		 1861 memcpy(session->metadata_cache->data +
1862 session->metadata_cache->metadata_written,
1863 str, len);
1864 session->metadata_cache->metadata_written += len;
c099397a 1865 kfree(str);
d83004aa 1866
d83004aa
JD		 1867 return 0;
1868
1869err:
1870 kfree(str);
1871 return -ENOMEM;
c099397a
MD		 1872}
1873
f513b2bf
MD		 1874static
1875int print_tabs(struct lttng_session *session, size_t nesting)
1876{
1877 size_t i;
1878
1879 for (i = 0; i < nesting; i++) {
1880 int ret;
1881
1882 ret = lttng_metadata_printf(session, " ");
1883 if (ret) {
1884 return ret;
1885 }
1886 }
1887 return 0;
1888}
1889
1890/*
1891 * Must be called with sessions_mutex held.
1892 */
1893static
1894int _lttng_struct_type_statedump(struct lttng_session *session,
1895 const struct lttng_type *type,
1896 size_t nesting)
1897{
1898 int ret;
1899 uint32_t i, nr_fields;
1900
1901 ret = print_tabs(session, nesting);
1902 if (ret)
1903 return ret;
1904 ret = lttng_metadata_printf(session,
1905 "struct {\n");
1906 if (ret)
1907 return ret;
1908 nr_fields = type->u._struct.nr_fields;
1909 for (i = 0; i < nr_fields; i++) {
1910 const struct lttng_event_field *iter_field;
1911
1912 iter_field = &type->u._struct.fields[i];
1913 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
1914 if (ret)
1915 return ret;
1916 }
1917 ret = print_tabs(session, nesting);
1918 if (ret)
1919 return ret;
1920 ret = lttng_metadata_printf(session,
1921 "}");
1922 return ret;
1923}
1924
1925/*
1926 * Must be called with sessions_mutex held.
1927 */
1928static
1929int _lttng_struct_statedump(struct lttng_session *session,
1930 const struct lttng_event_field *field,
1931 size_t nesting)
1932{
1933 int ret;
1934
1935 ret = _lttng_struct_type_statedump(session,
1936 &field->type, nesting);
1937 if (ret)
1938 return ret;
1939 ret = lttng_metadata_printf(session,
1940 "_%s;\n",
1941 field->name);
1942 return ret;
1943}
1944
65c85aa6
MD		 1945/*
1946 * Must be called with sessions_mutex held.
1947 */
1948static
1949int _lttng_variant_type_statedump(struct lttng_session *session,
1950 const struct lttng_type *type,
1951 size_t nesting)
1952{
1953 int ret;
1954 uint32_t i, nr_choices;
1955
1956 ret = print_tabs(session, nesting);
1957 if (ret)
1958 return ret;
1959 ret = lttng_metadata_printf(session,
1960 "variant <_%s> {\n",
1961 type->u.variant.tag_name);
1962 if (ret)
1963 return ret;
1964 nr_choices = type->u.variant.nr_choices;
1965 for (i = 0; i < nr_choices; i++) {
1966 const struct lttng_event_field *iter_field;
1967
1968 iter_field = &type->u.variant.choices[i];
1969 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
1970 if (ret)
1971 return ret;
1972 }
1973 ret = print_tabs(session, nesting);
1974 if (ret)
1975 return ret;
1976 ret = lttng_metadata_printf(session,
1977 "}");
1978 return ret;
1979}
1980
1981/*
1982 * Must be called with sessions_mutex held.
1983 */
1984static
1985int _lttng_variant_statedump(struct lttng_session *session,
1986 const struct lttng_event_field *field,
1987 size_t nesting)
1988{
1989 int ret;
1990
1991 ret = _lttng_variant_type_statedump(session,
1992 &field->type, nesting);
1993 if (ret)
1994 return ret;
1995 ret = lttng_metadata_printf(session,
1996 "_%s;\n",
1997 field->name);
1998 return ret;
1999}
2000
f513b2bf
MD		 2001/*
2002 * Must be called with sessions_mutex held.
2003 */
2004static
2005int _lttng_array_compound_statedump(struct lttng_session *session,
2006 const struct lttng_event_field *field,
2007 size_t nesting)
2008{
2009 int ret;
2010 const struct lttng_type *elem_type;
2011
65c85aa6 2012 /* Only array of structures and variants are currently supported. */
f513b2bf
MD		 2013 elem_type = field->type.u.array_compound.elem_type;
2014 switch (elem_type->atype) {
2015 case atype_struct:
2016 ret = _lttng_struct_type_statedump(session, elem_type, nesting);
2017 if (ret)
2018 return ret;
2019 break;
65c85aa6
MD		 2020 case atype_variant:
2021 ret = _lttng_variant_type_statedump(session, elem_type, nesting);
2022 if (ret)
2023 return ret;
2024 break;
f513b2bf
MD		 2025 default:
2026 return -EINVAL;
2027 }
2028 ret = lttng_metadata_printf(session,
2029 " _%s[%u];\n",
2030 field->name,
2031 field->type.u.array_compound.length);
2032 return ret;
2033}
2034
2035/*
2036 * Must be called with sessions_mutex held.
2037 */
2038static
2039int _lttng_sequence_compound_statedump(struct lttng_session *session,
2040 const struct lttng_event_field *field,
2041 size_t nesting)
2042{
2043 int ret;
2044 const char *length_name;
2045 const struct lttng_type *elem_type;
2046
2047 length_name = field->type.u.sequence_compound.length_name;
2048
65c85aa6 2049 /* Only array of structures and variants are currently supported. */
f513b2bf
MD		 2050 elem_type = field->type.u.sequence_compound.elem_type;
2051 switch (elem_type->atype) {
2052 case atype_struct:
2053 ret = _lttng_struct_type_statedump(session, elem_type, nesting);
2054 if (ret)
2055 return ret;
2056 break;
65c85aa6
MD		 2057 case atype_variant:
2058 ret = _lttng_variant_type_statedump(session, elem_type, nesting);
2059 if (ret)
2060 return ret;
2061 break;
f513b2bf
MD		 2062 default:
2063 return -EINVAL;
2064 }
2065 ret = lttng_metadata_printf(session,
2066 " _%s[ _%s ];\n",
2067 field->name,
2068 length_name);
2069 return ret;
2070}
2071
141ddf28
MD		 2072/*
2073 * Must be called with sessions_mutex held.
2074 */
2075static
2076int _lttng_enum_statedump(struct lttng_session *session,
2077 const struct lttng_event_field *field,
2078 size_t nesting)
2079{
2080 const struct lttng_enum_desc *enum_desc;
2081 const struct lttng_integer_type *container_type;
2082 int ret;
2083 unsigned int i, nr_entries;
2084
2085 enum_desc = field->type.u.basic.enumeration.desc;
2086 container_type = &field->type.u.basic.enumeration.container_type;
2087 nr_entries = enum_desc->nr_entries;
2088
2089 ret = print_tabs(session, nesting);
2090 if (ret)
2091 goto end;
2092 ret = lttng_metadata_printf(session,
578e68ec 2093 "enum : integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } {\n",
141ddf28
MD		 2094 container_type->size,
2095 container_type->alignment,
2096 container_type->signedness,
2097 (container_type->encoding == lttng_encode_none)
2098 ? "none"
2099 : (container_type->encoding == lttng_encode_UTF8)
2100 ? "UTF8"
2101 : "ASCII",
578e68ec
GB		 2102 container_type->base,
2103#if __BYTE_ORDER == __BIG_ENDIAN
2104 container_type->reverse_byte_order ? " byte_order = le;" : ""
2105#else
2106 container_type->reverse_byte_order ? " byte_order = be;" : ""
2107#endif
2108 );
141ddf28
MD		 2109 if (ret)
2110 goto end;
2111 /* Dump all entries */
2112 for (i = 0; i < nr_entries; i++) {
2113 const struct lttng_enum_entry *entry = &enum_desc->entries[i];
2114 int j, len;
2115
2116 ret = print_tabs(session, nesting + 1);
2117 if (ret)
2118 goto end;
2119 ret = lttng_metadata_printf(session,
2120 "\"");
2121 if (ret)
2122 goto end;
2123 len = strlen(entry->string);
2124 /* Escape the character '"' */
2125 for (j = 0; j < len; j++) {
2126 char c = entry->string[j];
2127
2128 switch (c) {
2129 case '"':
2130 ret = lttng_metadata_printf(session,
2131 "\\\"");
2132 break;
2133 case '\\':
2134 ret = lttng_metadata_printf(session,
2135 "\\\\");
2136 break;
2137 default:
2138 ret = lttng_metadata_printf(session,
2139 "%c", c);
2140 break;
2141 }
2142 if (ret)
2143 goto end;
2144 }
08ad1061
PP		 2145 ret = lttng_metadata_printf(session, "\"");
2146 if (ret)
2147 goto end;
2148
2149 if (entry->options.is_auto) {
2150 ret = lttng_metadata_printf(session, ",\n");
2151 if (ret)
2152 goto end;
141ddf28 2153 } else {
7c559490
MD		 2154 ret = lttng_metadata_printf(session,
2155 " = ");
2156 if (ret)
2157 goto end;
2158 if (entry->start.signedness)
141ddf28 2159 ret = lttng_metadata_printf(session,
7c559490
MD		 2160 "%lld", (long long) entry->start.value);
2161 else
2162 ret = lttng_metadata_printf(session,
2163 "%llu", entry->start.value);
2164 if (ret)
2165 goto end;
2166 if (entry->start.signedness == entry->end.signedness &&
2167 entry->start.value
2168 == entry->end.value) {
141ddf28 2169 ret = lttng_metadata_printf(session,
7c559490
MD		 2170 ",\n");
2171 } else {
2172 if (entry->end.signedness) {
2173 ret = lttng_metadata_printf(session,
2174 " ... %lld,\n",
2175 (long long) entry->end.value);
2176 } else {
2177 ret = lttng_metadata_printf(session,
2178 " ... %llu,\n",
2179 entry->end.value);
2180 }
141ddf28 2181 }
7c559490
MD		 2182 if (ret)
2183 goto end;
141ddf28 2184 }
141ddf28
MD		 2185 }
2186 ret = print_tabs(session, nesting);
2187 if (ret)
2188 goto end;
2189 ret = lttng_metadata_printf(session, "} _%s;\n",
2190 field->name);
2191end:
2192 return ret;
2193}
2194
d83004aa
JD		 2195/*
2196 * Must be called with sessions_mutex held.
2197 */
c099397a 2198static
a90917c3 2199int _lttng_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2200 const struct lttng_event_field *field,
2201 size_t nesting)
c099397a 2202{
c099397a 2203 int ret = 0;
c099397a 2204
8070f5c0
MD		 2205 switch (field->type.atype) {
2206 case atype_integer:
f513b2bf
MD		 2207 ret = print_tabs(session, nesting);
2208 if (ret)
2209 return ret;
8070f5c0 2210 ret = lttng_metadata_printf(session,
f513b2bf 2211 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
8070f5c0
MD		 2212 field->type.u.basic.integer.size,
2213 field->type.u.basic.integer.alignment,
2214 field->type.u.basic.integer.signedness,
2215 (field->type.u.basic.integer.encoding == lttng_encode_none)
2216 ? "none"
2217 : (field->type.u.basic.integer.encoding == lttng_encode_UTF8)
2218 ? "UTF8"
2219 : "ASCII",
2220 field->type.u.basic.integer.base,
5214fa50 2221#if __BYTE_ORDER == __BIG_ENDIAN
8070f5c0 2222 field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
c099397a 2223#else
8070f5c0 2224 field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
c099397a 2225#endif
8070f5c0
MD		 2226 field->name);
2227 break;
2228 case atype_enum:
141ddf28 2229 ret = _lttng_enum_statedump(session, field, nesting);
8070f5c0
MD		 2230 break;
2231 case atype_array:
3834b99f 2232 case atype_array_bitfield:
8070f5c0
MD		 2233 {
2234 const struct lttng_basic_type *elem_type;
2235
2236 elem_type = &field->type.u.array.elem_type;
43803cf2 2237 if (field->type.u.array.elem_alignment) {
f513b2bf
MD		 2238 ret = print_tabs(session, nesting);
2239 if (ret)
2240 return ret;
43803cf2 2241 ret = lttng_metadata_printf(session,
f513b2bf 2242 "struct { } align(%u) _%s_padding;\n",
43803cf2
MD		 2243 field->type.u.array.elem_alignment * CHAR_BIT,
2244 field->name);
2245 if (ret)
2246 return ret;
2247 }
f513b2bf
MD		 2248 ret = print_tabs(session, nesting);
2249 if (ret)
2250 return ret;
8070f5c0 2251 ret = lttng_metadata_printf(session,
f513b2bf 2252 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
8070f5c0
MD		 2253 elem_type->u.basic.integer.size,
2254 elem_type->u.basic.integer.alignment,
2255 elem_type->u.basic.integer.signedness,
2256 (elem_type->u.basic.integer.encoding == lttng_encode_none)
2257 ? "none"
2258 : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8)
2259 ? "UTF8"
2260 : "ASCII",
2261 elem_type->u.basic.integer.base,
5214fa50 2262#if __BYTE_ORDER == __BIG_ENDIAN
8070f5c0 2263 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
8fa75f34 2264#else
8070f5c0 2265 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
8fa75f34 2266#endif
8070f5c0
MD		 2267 field->name, field->type.u.array.length);
2268 break;
2269 }
2270 case atype_sequence:
3834b99f 2271 case atype_sequence_bitfield:
8070f5c0
MD		 2272 {
2273 const struct lttng_basic_type *elem_type;
2274 const struct lttng_basic_type *length_type;
2275
2276 elem_type = &field->type.u.sequence.elem_type;
2277 length_type = &field->type.u.sequence.length_type;
f513b2bf
MD		 2278 ret = print_tabs(session, nesting);
2279 if (ret)
2280 return ret;
8070f5c0 2281 ret = lttng_metadata_printf(session,
f513b2bf 2282 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
8070f5c0 2283 length_type->u.basic.integer.size,
32257272 2284 (unsigned int) length_type->u.basic.integer.alignment,
8070f5c0
MD		 2285 length_type->u.basic.integer.signedness,
2286 (length_type->u.basic.integer.encoding == lttng_encode_none)
2287 ? "none"
0635cdd4 2288 : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8)
8070f5c0 2289 ? "UTF8"
0635cdd4 2290 : "ASCII"),
8070f5c0 2291 length_type->u.basic.integer.base,
5214fa50 2292#if __BYTE_ORDER == __BIG_ENDIAN
8070f5c0 2293 length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
e0a7a7c4 2294#else
0635cdd4 2295 length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
e0a7a7c4 2296#endif
27d2368e
MD		 2297 field->name);
2298 if (ret)
2299 return ret;
2300
43803cf2 2301 if (field->type.u.sequence.elem_alignment) {
f513b2bf
MD		 2302 ret = print_tabs(session, nesting);
2303 if (ret)
2304 return ret;
43803cf2 2305 ret = lttng_metadata_printf(session,
f513b2bf 2306 "struct { } align(%u) _%s_padding;\n",
43803cf2
MD		 2307 field->type.u.sequence.elem_alignment * CHAR_BIT,
2308 field->name);
2309 if (ret)
2310 return ret;
2311 }
f513b2bf
MD		 2312 ret = print_tabs(session, nesting);
2313 if (ret)
2314 return ret;
27d2368e 2315 ret = lttng_metadata_printf(session,
f513b2bf 2316 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
8070f5c0 2317 elem_type->u.basic.integer.size,
32257272 2318 (unsigned int) elem_type->u.basic.integer.alignment,
8070f5c0
MD		 2319 elem_type->u.basic.integer.signedness,
2320 (elem_type->u.basic.integer.encoding == lttng_encode_none)
2321 ? "none"
0635cdd4 2322 : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8)
8070f5c0 2323 ? "UTF8"
0635cdd4 2324 : "ASCII"),
8070f5c0 2325 elem_type->u.basic.integer.base,
5214fa50 2326#if __BYTE_ORDER == __BIG_ENDIAN
8070f5c0 2327 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "",
8fa75f34 2328#else
8070f5c0 2329 elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "",
8fa75f34 2330#endif
8070f5c0 2331 field->name,
27d2368e 2332 field->name);
8070f5c0
MD		 2333 break;
2334 }
c099397a 2335
8070f5c0
MD		 2336 case atype_string:
2337 /* Default encoding is UTF8 */
f513b2bf
MD		 2338 ret = print_tabs(session, nesting);
2339 if (ret)
2340 return ret;
8070f5c0 2341 ret = lttng_metadata_printf(session,
f513b2bf 2342 "string%s _%s;\n",
8070f5c0
MD		 2343 field->type.u.basic.string.encoding == lttng_encode_ASCII ?
2344 " { encoding = ASCII; }" : "",
2345 field->name);
2346 break;
f513b2bf
MD		 2347 case atype_struct:
2348 ret = _lttng_struct_statedump(session, field, nesting);
2349 break;
2350 case atype_array_compound:
2351 ret = _lttng_array_compound_statedump(session, field, nesting);
2352 break;
2353 case atype_sequence_compound:
2354 ret = _lttng_sequence_compound_statedump(session, field, nesting);
2355 break;
65c85aa6
MD		 2356 case atype_variant:
2357 ret = _lttng_variant_statedump(session, field, nesting);
2358 break;
f513b2bf 2359
8070f5c0
MD		 2360 default:
2361 WARN_ON_ONCE(1);
2362 return -EINVAL;
2363 }
2364 return ret;
2365}
2366
2367static
a90917c3 2368int _lttng_context_metadata_statedump(struct lttng_session *session,
8070f5c0
MD		 2369 struct lttng_ctx *ctx)
2370{
2371 int ret = 0;
2372 int i;
2373
2374 if (!ctx)
2375 return 0;
2376 for (i = 0; i < ctx->nr_fields; i++) {
2377 const struct lttng_ctx_field *field = &ctx->fields[i];
2378
f513b2bf 2379 ret = _lttng_field_statedump(session, &field->event_field, 2);
8070f5c0
MD		 2380 if (ret)
2381 return ret;
2382 }
2383 return ret;
2384}
2385
2386static
a90917c3
MD		 2387int _lttng_fields_metadata_statedump(struct lttng_session *session,
2388 struct lttng_event *event)
8070f5c0
MD		 2389{
2390 const struct lttng_event_desc *desc = event->desc;
2391 int ret = 0;
2392 int i;
2393
2394 for (i = 0; i < desc->nr_fields; i++) {
2395 const struct lttng_event_field *field = &desc->fields[i];
2396
f513b2bf 2397 ret = _lttng_field_statedump(session, field, 2);
8070f5c0
MD		 2398 if (ret)
2399 return ret;
c099397a
MD		 2400 }
2401 return ret;
2402}
2403
d83004aa
JD		 2404/*
2405 * Must be called with sessions_mutex held.
122c63cb
MD		 2406 * The entire event metadata is printed as a single atomic metadata
2407 * transaction.
d83004aa 2408 */
c099397a 2409static
a90917c3
MD		 2410int _lttng_event_metadata_statedump(struct lttng_session *session,
2411 struct lttng_channel *chan,
2412 struct lttng_event *event)
c099397a
MD		 2413{
2414 int ret = 0;
2415
57ccbfa6 2416 if (event->metadata_dumped || !LTTNG_READ_ONCE(session->active))
c099397a 2417 return 0;
d83004aa 2418 if (chan->channel_type == METADATA_CHANNEL)
c099397a
MD		 2419 return 0;
2420
122c63cb
MD		 2421 lttng_metadata_begin(session);
2422
c099397a
MD		 2423 ret = lttng_metadata_printf(session,
2424 "event {\n"
ae734547 2425 " name = \"%s\";\n"
c099397a 2426 " id = %u;\n"
b9074a1b 2427 " stream_id = %u;\n",
c099397a
MD		 2428 event->desc->name,
2429 event->id,
2430 event->chan->id);
2431 if (ret)
2432 goto end;
2433
b9074a1b
MD		 2434 if (event->ctx) {
2435 ret = lttng_metadata_printf(session,
2436 " context := struct {\n");
2437 if (ret)
2438 goto end;
2439 }
a90917c3 2440 ret = _lttng_context_metadata_statedump(session, event->ctx);
8070f5c0
MD		 2441 if (ret)
2442 goto end;
b9074a1b
MD		 2443 if (event->ctx) {
2444 ret = lttng_metadata_printf(session,
2445 " };\n");
2446 if (ret)
2447 goto end;
2448 }
8070f5c0
MD		 2449
2450 ret = lttng_metadata_printf(session,
8070f5c0
MD		 2451 " fields := struct {\n"
2452 );
2453 if (ret)
2454 goto end;
2455
a90917c3 2456 ret = _lttng_fields_metadata_statedump(session, event);
c099397a
MD		 2457 if (ret)
2458 goto end;
2459
2460 /*
2461 * LTTng space reservation can only reserve multiples of the
2462 * byte size.
2463 */
2464 ret = lttng_metadata_printf(session,
9115fbdc
MD		 2465 " };\n"
2466 "};\n\n");
c099397a
MD		 2467 if (ret)
2468 goto end;
2469
c099397a
MD		 2470 event->metadata_dumped = 1;
2471end:
122c63cb 2472 lttng_metadata_end(session);
c099397a
MD		 2473 return ret;
2474
2475}
2476
d83004aa
JD		 2477/*
2478 * Must be called with sessions_mutex held.
122c63cb
MD		 2479 * The entire channel metadata is printed as a single atomic metadata
2480 * transaction.
d83004aa 2481 */
c099397a 2482static
a90917c3
MD		 2483int _lttng_channel_metadata_statedump(struct lttng_session *session,
2484 struct lttng_channel *chan)
c099397a
MD		 2485{
2486 int ret = 0;
2487
57ccbfa6 2488 if (chan->metadata_dumped || !LTTNG_READ_ONCE(session->active))
c099397a 2489 return 0;
d83004aa
JD		 2490
2491 if (chan->channel_type == METADATA_CHANNEL)
c099397a
MD		 2492 return 0;
2493
122c63cb
MD		 2494 lttng_metadata_begin(session);
2495
c099397a
MD		 2496 WARN_ON_ONCE(!chan->header_type);
2497 ret = lttng_metadata_printf(session,
2498 "stream {\n"
2499 " id = %u;\n"
9115fbdc 2500 " event.header := %s;\n"
b9074a1b 2501 " packet.context := struct packet_context;\n",
c099397a
MD		 2502 chan->id,
2503 chan->header_type == 1 ? "struct event_header_compact" :
2504 "struct event_header_large");
2505 if (ret)
2506 goto end;
2507
b9074a1b
MD		 2508 if (chan->ctx) {
2509 ret = lttng_metadata_printf(session,
2510 " event.context := struct {\n");
2511 if (ret)
2512 goto end;
2513 }
a90917c3 2514 ret = _lttng_context_metadata_statedump(session, chan->ctx);
8070f5c0
MD		 2515 if (ret)
2516 goto end;
b9074a1b
MD		 2517 if (chan->ctx) {
2518 ret = lttng_metadata_printf(session,
2519 " };\n");
2520 if (ret)
2521 goto end;
2522 }
8070f5c0
MD		 2523
2524 ret = lttng_metadata_printf(session,
b9074a1b 2525 "};\n\n");
8070f5c0 2526
c099397a
MD		 2527 chan->metadata_dumped = 1;
2528end:
122c63cb 2529 lttng_metadata_end(session);
c099397a
MD		 2530 return ret;
2531}
2532
d83004aa
JD		 2533/*
2534 * Must be called with sessions_mutex held.
2535 */
9115fbdc 2536static
a90917c3 2537int _lttng_stream_packet_context_declare(struct lttng_session *session)
9115fbdc
MD		 2538{
2539 return lttng_metadata_printf(session,
2540 "struct packet_context {\n"
a3ccff4f
MD		 2541 " uint64_clock_monotonic_t timestamp_begin;\n"
2542 " uint64_clock_monotonic_t timestamp_end;\n"
576ca06a
MD		 2543 " uint64_t content_size;\n"
2544 " uint64_t packet_size;\n"
5b3cf4f9 2545 " uint64_t packet_seq_num;\n"
a9afe705 2546 " unsigned long events_discarded;\n"
9115fbdc 2547 " uint32_t cpu_id;\n"
c6dfdf6f 2548 "};\n\n"
9115fbdc
MD		 2549 );
2550}
2551
2552/*
2553 * Compact header:
2554 * id: range: 0 - 30.
2555 * id 31 is reserved to indicate an extended header.
2556 *
2557 * Large header:
2558 * id: range: 0 - 65534.
2559 * id 65535 is reserved to indicate an extended header.
d83004aa
JD		 2560 *
2561 * Must be called with sessions_mutex held.
9115fbdc
MD		 2562 */
2563static
a90917c3 2564int _lttng_event_header_declare(struct lttng_session *session)
9115fbdc
MD		 2565{
2566 return lttng_metadata_printf(session,
2567 "struct event_header_compact {\n"
2568 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
2569 " variant <id> {\n"
2570 " struct {\n"
a3ccff4f 2571 " uint27_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2572 " } compact;\n"
2573 " struct {\n"
2574 " uint32_t id;\n"
a3ccff4f 2575 " uint64_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2576 " } extended;\n"
2577 " } v;\n"
2578 "} align(%u);\n"
2579 "\n"
2580 "struct event_header_large {\n"
2581 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
2582 " variant <id> {\n"
2583 " struct {\n"
a3ccff4f 2584 " uint32_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2585 " } compact;\n"
2586 " struct {\n"
2587 " uint32_t id;\n"
a3ccff4f 2588 " uint64_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2589 " } extended;\n"
2590 " } v;\n"
2591 "} align(%u);\n\n",
a90917c3
MD		 2592 lttng_alignof(uint32_t) * CHAR_BIT,
2593 lttng_alignof(uint16_t) * CHAR_BIT
9115fbdc
MD		 2594 );
2595}
2596
a3ccff4f
MD		 2597 /*
2598 * Approximation of NTP time of day to clock monotonic correlation,
2599 * taken at start of trace.
2600 * Yes, this is only an approximation. Yes, we can (and will) do better
2601 * in future versions.
5283350b
MD		 2602 * This function may return a negative offset. It may happen if the
2603 * system sets the REALTIME clock to 0 after boot.
72dc372e
MJ		 2604 *
2605 * Use 64bit timespec on kernels that have it, this makes 32bit arch
2606 * y2038 compliant.
a3ccff4f
MD		 2607 */
2608static
8967b2a3 2609int64_t measure_clock_offset(void)
a3ccff4f 2610{
dcb93448 2611 uint64_t monotonic_avg, monotonic[2], realtime;
2754583e 2612 uint64_t tcf = trace_clock_freq();
dcb93448 2613 int64_t offset;
a3ccff4f 2614 unsigned long flags;
72dc372e
MJ		 2615#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2616 struct timespec64 rts = { 0, 0 };
2617#else
2618 struct timespec rts = { 0, 0 };
2619#endif
a3ccff4f
MD		 2620
2621 /* Disable interrupts to increase correlation precision. */
2622 local_irq_save(flags);
2623 monotonic[0] = trace_clock_read64();
72dc372e
MJ		 2624#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2625 ktime_get_real_ts64(&rts);
2626#else
216b6baa 2627 getnstimeofday(&rts);
72dc372e 2628#endif
a3ccff4f
MD		 2629 monotonic[1] = trace_clock_read64();
2630 local_irq_restore(flags);
2631
dcb93448 2632 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
2754583e
MD		 2633 realtime = (uint64_t) rts.tv_sec * tcf;
2634 if (tcf == NSEC_PER_SEC) {
2635 realtime += rts.tv_nsec;
2636 } else {
2637 uint64_t n = rts.tv_nsec * tcf;
2638
2639 do_div(n, NSEC_PER_SEC);
2640 realtime += n;
2641 }
dcb93448 2642 offset = (int64_t) realtime - monotonic_avg;
a3ccff4f
MD		 2643 return offset;
2644}
2645
3eb95be4
JR		 2646static
2647int print_escaped_ctf_string(struct lttng_session *session, const char *string)
2648{
ae457be2 2649 int ret = 0;
3eb95be4
JR		 2650 size_t i;
2651 char cur;
2652
2653 i = 0;
2654 cur = string[i];
2655 while (cur != '\0') {
2656 switch (cur) {
2657 case '\n':
2658 ret = lttng_metadata_printf(session, "%s", "\\n");
2659 break;
2660 case '\\':
2661 case '"':
2662 ret = lttng_metadata_printf(session, "%c", '\\');
2663 if (ret)
2664 goto error;
2665 /* We still print the current char */
1d00109f 2666 lttng_fallthrough;
3eb95be4
JR		 2667 default:
2668 ret = lttng_metadata_printf(session, "%c", cur);
2669 break;
2670 }
2671
2672 if (ret)
2673 goto error;
2674
2675 cur = string[++i];
2676 }
2677error:
2678 return ret;
2679}
2680
2681static
1c88f269
JR		 2682int print_metadata_escaped_field(struct lttng_session *session, const char *field,
2683 const char *field_value)
3eb95be4
JR		 2684{
2685 int ret;
2686
1c88f269 2687 ret = lttng_metadata_printf(session, " %s = \"", field);
3eb95be4
JR		 2688 if (ret)
2689 goto error;
2690
1c88f269 2691 ret = print_escaped_ctf_string(session, field_value);
3eb95be4
JR		 2692 if (ret)
2693 goto error;
2694
2695 ret = lttng_metadata_printf(session, "\";\n");
2696
2697error:
2698 return ret;
2699}
2700
c099397a
MD		 2701/*
2702 * Output metadata into this session's metadata buffers.
d83004aa 2703 * Must be called with sessions_mutex held.
c099397a
MD		 2704 */
2705static
a90917c3 2706int _lttng_session_metadata_statedump(struct lttng_session *session)
c099397a 2707{
30bdb6e4 2708 unsigned char *uuid_c = session->uuid.b;
a82c63f1 2709 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
c88f762e 2710 const char *product_uuid;
a90917c3
MD		 2711 struct lttng_channel *chan;
2712 struct lttng_event *event;
c099397a
MD		 2713 int ret = 0;
2714
57ccbfa6 2715 if (!LTTNG_READ_ONCE(session->active))
c099397a 2716 return 0;
122c63cb
MD		 2717
2718 lttng_metadata_begin(session);
2719
c099397a
MD		 2720 if (session->metadata_dumped)
2721 goto skip_session;
c099397a 2722
d793d5e1 2723 snprintf(uuid_s, sizeof(uuid_s),
30bdb6e4
MD		 2724 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
2725 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
2726 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
2727 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
2728 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
d793d5e1
MD		 2729
2730 ret = lttng_metadata_printf(session,
9115fbdc
MD		 2731 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
2732 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
2733 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
2734 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
a9afe705 2735 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
9115fbdc
MD		 2736 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
2737 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
d793d5e1
MD		 2738 "\n"
2739 "trace {\n"
2740 " major = %u;\n"
2741 " minor = %u;\n"
30bdb6e4 2742 " uuid = \"%s\";\n"
d793d5e1
MD		 2743 " byte_order = %s;\n"
2744 " packet.header := struct {\n"
2745 " uint32_t magic;\n"
1ec3f75a 2746 " uint8_t uuid[16];\n"
d793d5e1 2747 " uint32_t stream_id;\n"
5594698f 2748 " uint64_t stream_instance_id;\n"
0eb25f58 2749 " };\n"
d793d5e1 2750 "};\n\n",
a90917c3
MD		 2751 lttng_alignof(uint8_t) * CHAR_BIT,
2752 lttng_alignof(uint16_t) * CHAR_BIT,
2753 lttng_alignof(uint32_t) * CHAR_BIT,
2754 lttng_alignof(uint64_t) * CHAR_BIT,
a9afe705
MD		 2755 sizeof(unsigned long) * CHAR_BIT,
2756 lttng_alignof(unsigned long) * CHAR_BIT,
c6c9e10f
MD		 2757 CTF_SPEC_MAJOR,
2758 CTF_SPEC_MINOR,
d793d5e1 2759 uuid_s,
5214fa50 2760#if __BYTE_ORDER == __BIG_ENDIAN
d793d5e1
MD		 2761 "be"
2762#else
2763 "le"
2764#endif
2765 );
2766 if (ret)
2767 goto end;
2768
99dc9597
MD		 2769 ret = lttng_metadata_printf(session,
2770 "env {\n"
a6058143 2771 " hostname = \"%s\";\n"
c6c9e10f 2772 " domain = \"kernel\";\n"
99dc9597 2773 " sysname = \"%s\";\n"
c6c9e10f
MD		 2774 " kernel_release = \"%s\";\n"
2775 " kernel_version = \"%s\";\n"
2776 " tracer_name = \"lttng-modules\";\n"
2777 " tracer_major = %d;\n"
2778 " tracer_minor = %d;\n"
2779 " tracer_patchlevel = %d;\n"
3eb95be4 2780 " trace_buffering_scheme = \"global\";\n",
3d0d43db 2781 current->nsproxy->uts_ns->name.nodename,
99dc9597
MD		 2782 utsname()->sysname,
2783 utsname()->release,
c6c9e10f
MD		 2784 utsname()->version,
2785 LTTNG_MODULES_MAJOR_VERSION,
2786 LTTNG_MODULES_MINOR_VERSION,
2787 LTTNG_MODULES_PATCHLEVEL_VERSION
99dc9597
MD		 2788 );
2789 if (ret)
2790 goto end;
2791
1c88f269
JR		 2792 ret = print_metadata_escaped_field(session, "trace_name", session->name);
2793 if (ret)
2794 goto end;
2795 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
2796 session->creation_time);
3eb95be4
JR		 2797 if (ret)
2798 goto end;
2799
c88f762e
GB		 2800 /* Add the product UUID to the 'env' section */
2801 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
2802 if (product_uuid) {
2803 ret = lttng_metadata_printf(session,
2804 " product_uuid = \"%s\";\n",
2805 product_uuid
2806 );
2807 if (ret)
2808 goto end;
2809 }
2810
2811 /* Close the 'env' section */
3eb95be4
JR		 2812 ret = lttng_metadata_printf(session, "};\n\n");
2813 if (ret)
2814 goto end;
2815
a3ccff4f
MD		 2816 ret = lttng_metadata_printf(session,
2817 "clock {\n"
2754583e
MD		 2818 " name = \"%s\";\n",
2819 trace_clock_name()
a82c63f1
MD		 2820 );
2821 if (ret)
2822 goto end;
2823
2824 if (!trace_clock_uuid(clock_uuid_s)) {
2825 ret = lttng_metadata_printf(session,
7c27cb17 2826 " uuid = \"%s\";\n",
a82c63f1
MD		 2827 clock_uuid_s
2828 );
2829 if (ret)
2830 goto end;
2831 }
2832
2833 ret = lttng_metadata_printf(session,
2754583e 2834 " description = \"%s\";\n"
a3ccff4f
MD		 2835 " freq = %llu; /* Frequency, in Hz */\n"
2836 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
8967b2a3 2837 " offset = %lld;\n"
a3ccff4f 2838 "};\n\n",
2754583e 2839 trace_clock_description(),
a3ccff4f 2840 (unsigned long long) trace_clock_freq(),
8967b2a3 2841 (long long) measure_clock_offset()
a3ccff4f
MD		 2842 );
2843 if (ret)
2844 goto end;
2845
2846 ret = lttng_metadata_printf(session,
2847 "typealias integer {\n"
2848 " size = 27; align = 1; signed = false;\n"
2754583e 2849 " map = clock.%s.value;\n"
a3ccff4f
MD		 2850 "} := uint27_clock_monotonic_t;\n"
2851 "\n"
2852 "typealias integer {\n"
2853 " size = 32; align = %u; signed = false;\n"
2754583e 2854 " map = clock.%s.value;\n"
a3ccff4f
MD		 2855 "} := uint32_clock_monotonic_t;\n"
2856 "\n"
2857 "typealias integer {\n"
2858 " size = 64; align = %u; signed = false;\n"
2754583e 2859 " map = clock.%s.value;\n"
a3ccff4f 2860 "} := uint64_clock_monotonic_t;\n\n",
2754583e 2861 trace_clock_name(),
a3ccff4f 2862 lttng_alignof(uint32_t) * CHAR_BIT,
2754583e
MD		 2863 trace_clock_name(),
2864 lttng_alignof(uint64_t) * CHAR_BIT,
2865 trace_clock_name()
a3ccff4f
MD		 2866 );
2867 if (ret)
2868 goto end;
2869
a90917c3 2870 ret = _lttng_stream_packet_context_declare(session);
9115fbdc
MD		 2871 if (ret)
2872 goto end;
2873
a90917c3 2874 ret = _lttng_event_header_declare(session);
9115fbdc
MD		 2875 if (ret)
2876 goto end;
2877
c099397a
MD		 2878skip_session:
2879 list_for_each_entry(chan, &session->chan, list) {
a90917c3 2880 ret = _lttng_channel_metadata_statedump(session, chan);
c099397a
MD		 2881 if (ret)
2882 goto end;
2883 }
2884
2885 list_for_each_entry(event, &session->events, list) {
a90917c3 2886 ret = _lttng_event_metadata_statedump(session, event->chan, event);
c099397a
MD		 2887 if (ret)
2888 goto end;
2889 }
2890 session->metadata_dumped = 1;
2891end:
122c63cb 2892 lttng_metadata_end(session);
c099397a
MD		 2893 return ret;
2894}
2895
c0e31d2e 2896/**
a90917c3 2897 * lttng_transport_register - LTT transport registration
c0e31d2e
MD		 2898 * @transport: transport structure
2899 *
2900 * Registers a transport which can be used as output to extract the data out of
2901 * LTTng. The module calling this registration function must ensure that no
2902 * trap-inducing code will be executed by the transport functions. E.g.
ea53823c 2903 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
c0e31d2e 2904 * is made visible to the transport function. This registration acts as a
ea53823c 2905 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
c0e31d2e
MD		 2906 * after its registration must it synchronize the TLBs.
2907 */
a90917c3 2908void lttng_transport_register(struct lttng_transport *transport)
c0e31d2e
MD		 2909{
2910 /*
2911 * Make sure no page fault can be triggered by the module about to be
2912 * registered. We deal with this here so we don't have to call
ea53823c 2913 * vmalloc_sync_mappings() in each module's init.
c0e31d2e 2914 */
ea53823c 2915 wrapper_vmalloc_sync_mappings();
c0e31d2e
MD		 2916
2917 mutex_lock(&sessions_mutex);
a90917c3 2918 list_add_tail(&transport->node, &lttng_transport_list);
c0e31d2e
MD		 2919 mutex_unlock(&sessions_mutex);
2920}
a90917c3 2921EXPORT_SYMBOL_GPL(lttng_transport_register);
c0e31d2e
MD		 2922
2923/**
a90917c3 2924 * lttng_transport_unregister - LTT transport unregistration
c0e31d2e
MD		 2925 * @transport: transport structure
2926 */
a90917c3 2927void lttng_transport_unregister(struct lttng_transport *transport)
c0e31d2e
MD		 2928{
2929 mutex_lock(&sessions_mutex);
2930 list_del(&transport->node);
2931 mutex_unlock(&sessions_mutex);
2932}
a90917c3 2933EXPORT_SYMBOL_GPL(lttng_transport_unregister);
c0e31d2e 2934
2d042821 2935#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0))
1e367326
MD		 2936
2937enum cpuhp_state lttng_hp_prepare;
2938enum cpuhp_state lttng_hp_online;
2939
2940static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
2941{
2942 struct lttng_cpuhp_node *lttng_node;
2943
2944 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2945 switch (lttng_node->component) {
2946 case LTTNG_RING_BUFFER_FRONTEND:
2947 return 0;
2948 case LTTNG_RING_BUFFER_BACKEND:
2949 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
2950 case LTTNG_RING_BUFFER_ITER:
2951 return 0;
2952 case LTTNG_CONTEXT_PERF_COUNTERS:
2953 return 0;
2954 default:
2955 return -EINVAL;
2956 }
2957}
2958
2959static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
2960{
2961 struct lttng_cpuhp_node *lttng_node;
2962
2963 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2964 switch (lttng_node->component) {
2965 case LTTNG_RING_BUFFER_FRONTEND:
2966 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
2967 case LTTNG_RING_BUFFER_BACKEND:
2968 return 0;
2969 case LTTNG_RING_BUFFER_ITER:
2970 return 0;
2971 case LTTNG_CONTEXT_PERF_COUNTERS:
2972 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
2973 default:
2974 return -EINVAL;
2975 }
2976}
2977
2978static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
2979{
2980 struct lttng_cpuhp_node *lttng_node;
2981
2982 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2983 switch (lttng_node->component) {
2984 case LTTNG_RING_BUFFER_FRONTEND:
2985 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
2986 case LTTNG_RING_BUFFER_BACKEND:
2987 return 0;
2988 case LTTNG_RING_BUFFER_ITER:
2989 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
2990 case LTTNG_CONTEXT_PERF_COUNTERS:
2991 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
2992 default:
2993 return -EINVAL;
2994 }
2995}
2996
2997static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
2998{
2999 struct lttng_cpuhp_node *lttng_node;
3000
3001 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3002 switch (lttng_node->component) {
3003 case LTTNG_RING_BUFFER_FRONTEND:
3004 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
3005 case LTTNG_RING_BUFFER_BACKEND:
3006 return 0;
3007 case LTTNG_RING_BUFFER_ITER:
3008 return 0;
3009 case LTTNG_CONTEXT_PERF_COUNTERS:
3010 return 0;
3011 default:
3012 return -EINVAL;
3013 }
3014}
3015
3016static int __init lttng_init_cpu_hotplug(void)
3017{
3018 int ret;
3019
3020 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
3021 lttng_hotplug_prepare,
3022 lttng_hotplug_dead);
3023 if (ret < 0) {
3024 return ret;
3025 }
3026 lttng_hp_prepare = ret;
3027 lttng_rb_set_hp_prepare(ret);
3028
3029 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
3030 lttng_hotplug_online,
3031 lttng_hotplug_offline);
3032 if (ret < 0) {
3033 cpuhp_remove_multi_state(lttng_hp_prepare);
3034 lttng_hp_prepare = 0;
3035 return ret;
3036 }
3037 lttng_hp_online = ret;
3038 lttng_rb_set_hp_online(ret);
3039
3040 return 0;
3041}
3042
3043static void __exit lttng_exit_cpu_hotplug(void)
3044{
3045 lttng_rb_set_hp_online(0);
3046 cpuhp_remove_multi_state(lttng_hp_online);
3047 lttng_rb_set_hp_prepare(0);
3048 cpuhp_remove_multi_state(lttng_hp_prepare);
3049}
3050
2d042821 3051#else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
1e367326
MD		 3052static int lttng_init_cpu_hotplug(void)
3053{
3054 return 0;
3055}
3056static void lttng_exit_cpu_hotplug(void)
3057{
3058}
2d042821 3059#endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
1e367326
MD		 3060
3061
a90917c3 3062static int __init lttng_events_init(void)
4e3c1b9b 3063{
1c25284c
MD		 3064 int ret;
3065
453b2495
JD		 3066 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
3067 if (ret)
3068 return ret;
389d7070 3069 ret = wrapper_get_pfnblock_flags_mask_init();
36561775
MD		 3070 if (ret)
3071 return ret;
3072 ret = wrapper_get_pageblock_flags_mask_init();
114667d5
MD		 3073 if (ret)
3074 return ret;
3075 ret = lttng_probes_init();
389d7070
MD		 3076 if (ret)
3077 return ret;
07dfc1d0 3078 ret = lttng_context_init();
20591cf7
MD		 3079 if (ret)
3080 return ret;
07dfc1d0
MD		 3081 ret = lttng_tracepoint_init();
3082 if (ret)
3083 goto error_tp;
a90917c3 3084 event_cache = KMEM_CACHE(lttng_event, 0);
20591cf7
MD		 3085 if (!event_cache) {
3086 ret = -ENOMEM;
3087 goto error_kmem;
3088 }
80996790 3089 ret = lttng_abi_init();
02119ee5
MD		 3090 if (ret)
3091 goto error_abi;
0c956676
MD		 3092 ret = lttng_logger_init();
3093 if (ret)
3094 goto error_logger;
1e367326
MD		 3095 ret = lttng_init_cpu_hotplug();
3096 if (ret)
3097 goto error_hotplug;
101215b7 3098 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3099 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3100 __stringify(LTTNG_MODULES_MINOR_VERSION),
3101 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3102 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3103 LTTNG_VERSION_NAME,
3104#ifdef LTTNG_EXTRA_VERSION_GIT
3105 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3106#else
3107 "",
3108#endif
3109#ifdef LTTNG_EXTRA_VERSION_NAME
3110 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3111#else
3112 "");
3113#endif
5e22c27b
MJ		 3114#ifdef CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM
3115 printk(KERN_NOTICE "LTTng: Experimental bitwise enum enabled.\n");
3116#endif /* CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM */
4e3c1b9b 3117 return 0;
0c956676 3118
1e367326
MD		 3119error_hotplug:
3120 lttng_logger_exit();
0c956676
MD		 3121error_logger:
3122 lttng_abi_exit();
02119ee5 3123error_abi:
1c25284c 3124 kmem_cache_destroy(event_cache);
20591cf7
MD		 3125error_kmem:
3126 lttng_tracepoint_exit();
07dfc1d0
MD		 3127error_tp:
3128 lttng_context_exit();
101215b7 3129 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3130 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3131 __stringify(LTTNG_MODULES_MINOR_VERSION),
3132 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3133 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3134 LTTNG_VERSION_NAME,
3135#ifdef LTTNG_EXTRA_VERSION_GIT
3136 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3137#else
3138 "",
3139#endif
3140#ifdef LTTNG_EXTRA_VERSION_NAME
3141 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3142#else
3143 "");
3144#endif
1c25284c 3145 return ret;
4e3c1b9b
MD		 3146}
3147
a90917c3 3148module_init(lttng_events_init);
11b5a3c2 3149
a90917c3 3150static void __exit lttng_events_exit(void)
4e3c1b9b 3151{
a90917c3 3152 struct lttng_session *session, *tmpsession;
92e94819 3153
1e367326 3154 lttng_exit_cpu_hotplug();
0c956676 3155 lttng_logger_exit();
80996790 3156 lttng_abi_exit();
92e94819 3157 list_for_each_entry_safe(session, tmpsession, &sessions, list)
a90917c3 3158 lttng_session_destroy(session);
11b5a3c2 3159 kmem_cache_destroy(event_cache);
20591cf7 3160 lttng_tracepoint_exit();
07dfc1d0 3161 lttng_context_exit();
101215b7 3162 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3163 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3164 __stringify(LTTNG_MODULES_MINOR_VERSION),
3165 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3166 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3167 LTTNG_VERSION_NAME,
3168#ifdef LTTNG_EXTRA_VERSION_GIT
3169 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3170#else
3171 "",
3172#endif
3173#ifdef LTTNG_EXTRA_VERSION_NAME
3174 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3175#else
3176 "");
3177#endif
4e3c1b9b 3178}
92e94819 3179
a90917c3 3180module_exit(lttng_events_exit);
11b5a3c2 3181
101215b7
MJ		 3182#include "extra_version/patches.i"
3183#ifdef LTTNG_EXTRA_VERSION_GIT
3184MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
3185#endif
3186#ifdef LTTNG_EXTRA_VERSION_NAME
3187MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
3188#endif
92e94819
MD		 3189MODULE_LICENSE("GPL and additional rights");
3190MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
1c124020 3191MODULE_DESCRIPTION("LTTng tracer");
9a9973ef
MD		 3192MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
3193 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
309370e2
MD		 3194 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
3195 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
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