Commit | Line | Data |
---|---|---|
4e3c1b9b | 1 | /* |
a90917c3 | 2 | * lttng-events.c |
4e3c1b9b | 3 | * |
4e3c1b9b | 4 | * Holds LTTng per-session event registry. |
17baffe2 | 5 | * |
886d51a3 MD |
6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
4e3c1b9b MD |
21 | */ |
22 | ||
23 | #include <linux/module.h> | |
c0e31d2e MD |
24 | #include <linux/mutex.h> |
25 | #include <linux/sched.h> | |
11b5a3c2 | 26 | #include <linux/slab.h> |
c099397a | 27 | #include <linux/jiffies.h> |
99dc9597 | 28 | #include <linux/utsname.h> |
abc0446a | 29 | #include <linux/err.h> |
7e6f9ef6 MD |
30 | #include <linux/seq_file.h> |
31 | #include <linux/file.h> | |
32 | #include <linux/anon_inodes.h> | |
33 | #include "wrapper/file.h" | |
3c997079 MD |
34 | #include <linux/jhash.h> |
35 | ||
a864fb02 | 36 | #include "wrapper/uuid.h" |
b13f3ebe | 37 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
a82c63f1 | 38 | #include "wrapper/random.h" |
3a523f5b | 39 | #include "wrapper/tracepoint.h" |
f934e302 | 40 | #include "wrapper/list.h" |
b8590f40 | 41 | #include "lttng-kernel-version.h" |
a90917c3 MD |
42 | #include "lttng-events.h" |
43 | #include "lttng-tracer.h" | |
6dccd6c1 | 44 | #include "lttng-abi-old.h" |
4e3c1b9b | 45 | |
d83004aa JD |
46 | #define METADATA_CACHE_DEFAULT_SIZE 4096 |
47 | ||
4e3c1b9b | 48 | static LIST_HEAD(sessions); |
a90917c3 | 49 | static LIST_HEAD(lttng_transport_list); |
d83004aa JD |
50 | /* |
51 | * Protect the sessions and metadata caches. | |
52 | */ | |
4e3c1b9b MD |
53 | static DEFINE_MUTEX(sessions_mutex); |
54 | static struct kmem_cache *event_cache; | |
55 | ||
3c997079 MD |
56 | static void lttng_session_lazy_sync_enablers(struct lttng_session *session); |
57 | static void lttng_session_sync_enablers(struct lttng_session *session); | |
58 | static void lttng_enabler_destroy(struct lttng_enabler *enabler); | |
59 | ||
a90917c3 MD |
60 | static void _lttng_event_destroy(struct lttng_event *event); |
61 | static void _lttng_channel_destroy(struct lttng_channel *chan); | |
62 | static int _lttng_event_unregister(struct lttng_event *event); | |
c099397a | 63 | static |
a90917c3 MD |
64 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
65 | struct lttng_channel *chan, | |
66 | struct lttng_event *event); | |
c099397a | 67 | static |
a90917c3 | 68 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
d83004aa JD |
69 | static |
70 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream); | |
c099397a | 71 | |
c099397a | 72 | void synchronize_trace(void) |
abcca994 MD |
73 | { |
74 | synchronize_sched(); | |
b8590f40 MD |
75 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
76 | #ifdef CONFIG_PREEMPT_RT_FULL | |
77 | synchronize_rcu(); | |
78 | #endif | |
79 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ | |
abcca994 MD |
80 | #ifdef CONFIG_PREEMPT_RT |
81 | synchronize_rcu(); | |
82 | #endif | |
b8590f40 | 83 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
abcca994 MD |
84 | } |
85 | ||
3c997079 MD |
86 | void lttng_lock_sessions(void) |
87 | { | |
88 | mutex_lock(&sessions_mutex); | |
89 | } | |
90 | ||
91 | void lttng_unlock_sessions(void) | |
92 | { | |
93 | mutex_unlock(&sessions_mutex); | |
94 | } | |
95 | ||
96 | /* | |
97 | * Called with sessions lock held. | |
98 | */ | |
99 | int lttng_session_active(void) | |
100 | { | |
101 | struct lttng_session *iter; | |
102 | ||
103 | list_for_each_entry(iter, &sessions, list) { | |
104 | if (iter->active) | |
105 | return 1; | |
106 | } | |
107 | return 0; | |
108 | } | |
109 | ||
a90917c3 | 110 | struct lttng_session *lttng_session_create(void) |
4e3c1b9b | 111 | { |
a90917c3 | 112 | struct lttng_session *session; |
d83004aa | 113 | struct lttng_metadata_cache *metadata_cache; |
3c997079 | 114 | int i; |
4e3c1b9b MD |
115 | |
116 | mutex_lock(&sessions_mutex); | |
a90917c3 | 117 | session = kzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
4e3c1b9b | 118 | if (!session) |
d83004aa | 119 | goto err; |
4e3c1b9b | 120 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 121 | INIT_LIST_HEAD(&session->events); |
d793d5e1 | 122 | uuid_le_gen(&session->uuid); |
d83004aa JD |
123 | |
124 | metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache), | |
125 | GFP_KERNEL); | |
126 | if (!metadata_cache) | |
127 | goto err_free_session; | |
128 | metadata_cache->data = kzalloc(METADATA_CACHE_DEFAULT_SIZE, | |
129 | GFP_KERNEL); | |
130 | if (!metadata_cache->data) | |
131 | goto err_free_cache; | |
132 | metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE; | |
133 | kref_init(&metadata_cache->refcount); | |
134 | session->metadata_cache = metadata_cache; | |
135 | INIT_LIST_HEAD(&metadata_cache->metadata_stream); | |
a36580d5 MD |
136 | memcpy(&metadata_cache->uuid, &session->uuid, |
137 | sizeof(metadata_cache->uuid)); | |
3c997079 MD |
138 | INIT_LIST_HEAD(&session->enablers_head); |
139 | for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++) | |
140 | INIT_HLIST_HEAD(&session->events_ht.table[i]); | |
4e3c1b9b MD |
141 | list_add(&session->list, &sessions); |
142 | mutex_unlock(&sessions_mutex); | |
143 | return session; | |
d83004aa JD |
144 | |
145 | err_free_cache: | |
146 | kfree(metadata_cache); | |
147 | err_free_session: | |
148 | kfree(session); | |
149 | err: | |
150 | mutex_unlock(&sessions_mutex); | |
151 | return NULL; | |
152 | } | |
153 | ||
154 | void metadata_cache_destroy(struct kref *kref) | |
155 | { | |
156 | struct lttng_metadata_cache *cache = | |
157 | container_of(kref, struct lttng_metadata_cache, refcount); | |
158 | kfree(cache->data); | |
159 | kfree(cache); | |
4e3c1b9b MD |
160 | } |
161 | ||
a90917c3 | 162 | void lttng_session_destroy(struct lttng_session *session) |
4e3c1b9b | 163 | { |
a90917c3 MD |
164 | struct lttng_channel *chan, *tmpchan; |
165 | struct lttng_event *event, *tmpevent; | |
d83004aa | 166 | struct lttng_metadata_stream *metadata_stream; |
3c997079 | 167 | struct lttng_enabler *enabler, *tmpenabler; |
dda6a249 | 168 | int ret; |
4e3c1b9b MD |
169 | |
170 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 171 | ACCESS_ONCE(session->active) = 0; |
1ec65de1 MD |
172 | list_for_each_entry(chan, &session->chan, list) { |
173 | ret = lttng_syscalls_unregister(chan); | |
174 | WARN_ON(ret); | |
175 | } | |
dda6a249 | 176 | list_for_each_entry(event, &session->events, list) { |
a90917c3 | 177 | ret = _lttng_event_unregister(event); |
dda6a249 MD |
178 | WARN_ON(ret); |
179 | } | |
abcca994 | 180 | synchronize_trace(); /* Wait for in-flight events to complete */ |
3c997079 MD |
181 | list_for_each_entry_safe(enabler, tmpenabler, |
182 | &session->enablers_head, node) | |
183 | lttng_enabler_destroy(enabler); | |
4e3c1b9b | 184 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
a90917c3 | 185 | _lttng_event_destroy(event); |
d83004aa JD |
186 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { |
187 | BUG_ON(chan->channel_type == METADATA_CHANNEL); | |
a90917c3 | 188 | _lttng_channel_destroy(chan); |
d83004aa JD |
189 | } |
190 | list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) | |
191 | _lttng_metadata_channel_hangup(metadata_stream); | |
e0130fab MD |
192 | if (session->pid_tracker) |
193 | lttng_pid_tracker_destroy(session->pid_tracker); | |
d83004aa | 194 | kref_put(&session->metadata_cache->refcount, metadata_cache_destroy); |
4e3c1b9b MD |
195 | list_del(&session->list); |
196 | mutex_unlock(&sessions_mutex); | |
197 | kfree(session); | |
198 | } | |
199 | ||
a90917c3 | 200 | int lttng_session_enable(struct lttng_session *session) |
c0e31d2e MD |
201 | { |
202 | int ret = 0; | |
a90917c3 | 203 | struct lttng_channel *chan; |
c0e31d2e MD |
204 | |
205 | mutex_lock(&sessions_mutex); | |
206 | if (session->active) { | |
207 | ret = -EBUSY; | |
208 | goto end; | |
209 | } | |
c099397a | 210 | |
3c997079 MD |
211 | /* Set transient enabler state to "enabled" */ |
212 | session->tstate = 1; | |
213 | ||
c099397a MD |
214 | /* |
215 | * Snapshot the number of events per channel to know the type of header | |
216 | * we need to use. | |
217 | */ | |
218 | list_for_each_entry(chan, &session->chan, list) { | |
219 | if (chan->header_type) | |
220 | continue; /* don't change it if session stop/restart */ | |
221 | if (chan->free_event_id < 31) | |
222 | chan->header_type = 1; /* compact */ | |
223 | else | |
224 | chan->header_type = 2; /* large */ | |
225 | } | |
226 | ||
3c997079 MD |
227 | /* We need to sync enablers with session before activation. */ |
228 | lttng_session_sync_enablers(session); | |
229 | ||
52fc2e1f | 230 | ACCESS_ONCE(session->active) = 1; |
8070f5c0 | 231 | ACCESS_ONCE(session->been_active) = 1; |
a90917c3 | 232 | ret = _lttng_session_metadata_statedump(session); |
c337ddc2 MD |
233 | if (ret) { |
234 | ACCESS_ONCE(session->active) = 0; | |
235 | goto end; | |
236 | } | |
237 | ret = lttng_statedump_start(session); | |
360f38ea | 238 | if (ret) |
c099397a | 239 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
240 | end: |
241 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 242 | return ret; |
c0e31d2e MD |
243 | } |
244 | ||
a90917c3 | 245 | int lttng_session_disable(struct lttng_session *session) |
c0e31d2e MD |
246 | { |
247 | int ret = 0; | |
248 | ||
249 | mutex_lock(&sessions_mutex); | |
250 | if (!session->active) { | |
251 | ret = -EBUSY; | |
252 | goto end; | |
253 | } | |
52fc2e1f | 254 | ACCESS_ONCE(session->active) = 0; |
3c997079 MD |
255 | |
256 | /* Set transient enabler state to "disabled" */ | |
257 | session->tstate = 0; | |
258 | lttng_session_sync_enablers(session); | |
c0e31d2e MD |
259 | end: |
260 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 261 | return ret; |
c0e31d2e MD |
262 | } |
263 | ||
a90917c3 | 264 | int lttng_channel_enable(struct lttng_channel *channel) |
e64957da | 265 | { |
3c997079 | 266 | int ret = 0; |
e64957da | 267 | |
3c997079 MD |
268 | mutex_lock(&sessions_mutex); |
269 | if (channel->channel_type == METADATA_CHANNEL) { | |
270 | ret = -EPERM; | |
271 | goto end; | |
272 | } | |
273 | if (channel->enabled) { | |
274 | ret = -EEXIST; | |
275 | goto end; | |
276 | } | |
277 | /* Set transient enabler state to "enabled" */ | |
278 | channel->tstate = 1; | |
279 | lttng_session_sync_enablers(channel->session); | |
280 | /* Set atomically the state to "enabled" */ | |
281 | ACCESS_ONCE(channel->enabled) = 1; | |
282 | end: | |
283 | mutex_unlock(&sessions_mutex); | |
284 | return ret; | |
e64957da MD |
285 | } |
286 | ||
a90917c3 | 287 | int lttng_channel_disable(struct lttng_channel *channel) |
e64957da | 288 | { |
3c997079 | 289 | int ret = 0; |
e64957da | 290 | |
3c997079 MD |
291 | mutex_lock(&sessions_mutex); |
292 | if (channel->channel_type == METADATA_CHANNEL) { | |
293 | ret = -EPERM; | |
294 | goto end; | |
295 | } | |
296 | if (!channel->enabled) { | |
297 | ret = -EEXIST; | |
298 | goto end; | |
299 | } | |
300 | /* Set atomically the state to "disabled" */ | |
301 | ACCESS_ONCE(channel->enabled) = 0; | |
302 | /* Set transient enabler state to "enabled" */ | |
303 | channel->tstate = 0; | |
304 | lttng_session_sync_enablers(channel->session); | |
305 | end: | |
306 | mutex_unlock(&sessions_mutex); | |
307 | return ret; | |
e64957da MD |
308 | } |
309 | ||
a90917c3 | 310 | int lttng_event_enable(struct lttng_event *event) |
e64957da | 311 | { |
3c997079 | 312 | int ret = 0; |
e64957da | 313 | |
3c997079 MD |
314 | mutex_lock(&sessions_mutex); |
315 | if (event->chan->channel_type == METADATA_CHANNEL) { | |
316 | ret = -EPERM; | |
317 | goto end; | |
318 | } | |
319 | if (event->enabled) { | |
320 | ret = -EEXIST; | |
321 | goto end; | |
322 | } | |
323 | ACCESS_ONCE(event->enabled) = 1; | |
324 | lttng_session_sync_enablers(event->chan->session); | |
325 | end: | |
326 | mutex_unlock(&sessions_mutex); | |
327 | return ret; | |
e64957da MD |
328 | } |
329 | ||
a90917c3 | 330 | int lttng_event_disable(struct lttng_event *event) |
e64957da | 331 | { |
3c997079 | 332 | int ret = 0; |
e64957da | 333 | |
3c997079 MD |
334 | mutex_lock(&sessions_mutex); |
335 | if (event->chan->channel_type == METADATA_CHANNEL) { | |
336 | ret = -EPERM; | |
337 | goto end; | |
338 | } | |
339 | if (!event->enabled) { | |
340 | ret = -EEXIST; | |
341 | goto end; | |
342 | } | |
343 | ACCESS_ONCE(event->enabled) = 0; | |
344 | lttng_session_sync_enablers(event->chan->session); | |
345 | end: | |
346 | mutex_unlock(&sessions_mutex); | |
347 | return ret; | |
e64957da MD |
348 | } |
349 | ||
a90917c3 | 350 | static struct lttng_transport *lttng_transport_find(const char *name) |
f3d01b96 | 351 | { |
a90917c3 | 352 | struct lttng_transport *transport; |
f3d01b96 | 353 | |
a90917c3 | 354 | list_for_each_entry(transport, <tng_transport_list, node) { |
f3d01b96 MD |
355 | if (!strcmp(transport->name, name)) |
356 | return transport; | |
357 | } | |
358 | return NULL; | |
359 | } | |
360 | ||
a90917c3 | 361 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
5dbbdb43 MD |
362 | const char *transport_name, |
363 | void *buf_addr, | |
4e3c1b9b MD |
364 | size_t subbuf_size, size_t num_subbuf, |
365 | unsigned int switch_timer_interval, | |
d83004aa JD |
366 | unsigned int read_timer_interval, |
367 | enum channel_type channel_type) | |
4e3c1b9b | 368 | { |
a90917c3 MD |
369 | struct lttng_channel *chan; |
370 | struct lttng_transport *transport = NULL; | |
4e3c1b9b MD |
371 | |
372 | mutex_lock(&sessions_mutex); | |
d83004aa | 373 | if (session->been_active && channel_type != METADATA_CHANNEL) |
e5382b6d | 374 | goto active; /* Refuse to add channel to active session */ |
a90917c3 | 375 | transport = lttng_transport_find(transport_name); |
f3d01b96 MD |
376 | if (!transport) { |
377 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
378 | transport_name); | |
c0e31d2e | 379 | goto notransport; |
f3d01b96 | 380 | } |
a33c9927 MD |
381 | if (!try_module_get(transport->owner)) { |
382 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
383 | goto notransport; | |
384 | } | |
a90917c3 | 385 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
4e3c1b9b | 386 | if (!chan) |
c0e31d2e | 387 | goto nomem; |
4e3c1b9b | 388 | chan->session = session; |
05d32c64 | 389 | chan->id = session->free_chan_id++; |
3b731ab1 | 390 | chan->ops = &transport->ops; |
125b4df4 MD |
391 | /* |
392 | * Note: the channel creation op already writes into the packet | |
393 | * headers. Therefore the "chan" information used as input | |
394 | * should be already accessible. | |
395 | */ | |
5f5ddf01 MD |
396 | chan->chan = transport->ops.channel_create(transport_name, |
397 | chan, buf_addr, subbuf_size, num_subbuf, | |
398 | switch_timer_interval, read_timer_interval); | |
f3d01b96 MD |
399 | if (!chan->chan) |
400 | goto create_error; | |
3c997079 | 401 | chan->tstate = 1; |
e64957da | 402 | chan->enabled = 1; |
a33c9927 | 403 | chan->transport = transport; |
d83004aa | 404 | chan->channel_type = channel_type; |
4e3c1b9b MD |
405 | list_add(&chan->list, &session->chan); |
406 | mutex_unlock(&sessions_mutex); | |
407 | return chan; | |
408 | ||
f3d01b96 MD |
409 | create_error: |
410 | kfree(chan); | |
c0e31d2e | 411 | nomem: |
a33c9927 MD |
412 | if (transport) |
413 | module_put(transport->owner); | |
c0e31d2e | 414 | notransport: |
e5382b6d | 415 | active: |
4e3c1b9b MD |
416 | mutex_unlock(&sessions_mutex); |
417 | return NULL; | |
418 | } | |
419 | ||
420 | /* | |
d83004aa JD |
421 | * Only used internally at session destruction for per-cpu channels, and |
422 | * when metadata channel is released. | |
423 | * Needs to be called with sessions mutex held. | |
4e3c1b9b | 424 | */ |
aa7c23a9 | 425 | static |
a90917c3 | 426 | void _lttng_channel_destroy(struct lttng_channel *chan) |
4e3c1b9b | 427 | { |
11b5a3c2 | 428 | chan->ops->channel_destroy(chan->chan); |
a33c9927 | 429 | module_put(chan->transport->owner); |
4e3c1b9b | 430 | list_del(&chan->list); |
8070f5c0 | 431 | lttng_destroy_context(chan->ctx); |
4e3c1b9b MD |
432 | kfree(chan); |
433 | } | |
434 | ||
d83004aa JD |
435 | void lttng_metadata_channel_destroy(struct lttng_channel *chan) |
436 | { | |
437 | BUG_ON(chan->channel_type != METADATA_CHANNEL); | |
438 | ||
439 | /* Protect the metadata cache with the sessions_mutex. */ | |
440 | mutex_lock(&sessions_mutex); | |
441 | _lttng_channel_destroy(chan); | |
442 | mutex_unlock(&sessions_mutex); | |
443 | } | |
444 | EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy); | |
445 | ||
446 | static | |
447 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream) | |
448 | { | |
449 | stream->finalized = 1; | |
450 | wake_up_interruptible(&stream->read_wait); | |
451 | } | |
452 | ||
e5382b6d MD |
453 | /* |
454 | * Supports event creation while tracing session is active. | |
3c997079 | 455 | * Needs to be called with sessions mutex held. |
e5382b6d | 456 | */ |
3c997079 MD |
457 | struct lttng_event *_lttng_event_create(struct lttng_channel *chan, |
458 | struct lttng_kernel_event *event_param, | |
459 | void *filter, | |
460 | const struct lttng_event_desc *event_desc, | |
461 | enum lttng_kernel_instrumentation itype) | |
4e3c1b9b | 462 | { |
3c997079 | 463 | struct lttng_session *session = chan->session; |
a90917c3 | 464 | struct lttng_event *event; |
3c997079 MD |
465 | const char *event_name; |
466 | struct hlist_head *head; | |
467 | size_t name_len; | |
468 | uint32_t hash; | |
3d084699 | 469 | int ret; |
4e3c1b9b | 470 | |
abc0446a | 471 | if (chan->free_event_id == -1U) { |
4cf0bf51 | 472 | ret = -EMFILE; |
e5382b6d | 473 | goto full; |
abc0446a | 474 | } |
3c997079 MD |
475 | |
476 | switch (itype) { | |
477 | case LTTNG_KERNEL_TRACEPOINT: | |
478 | event_name = event_desc->name; | |
479 | break; | |
480 | case LTTNG_KERNEL_KPROBE: | |
481 | case LTTNG_KERNEL_KRETPROBE: | |
482 | case LTTNG_KERNEL_FUNCTION: | |
483 | case LTTNG_KERNEL_NOOP: | |
484 | event_name = event_param->name; | |
485 | break; | |
486 | default: | |
487 | WARN_ON_ONCE(1); | |
488 | ret = -EINVAL; | |
489 | goto type_error; | |
490 | } | |
491 | name_len = strlen(event_name); | |
492 | hash = jhash(event_name, name_len, 0); | |
493 | head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; | |
494 | hlist_for_each_entry(event, head, hlist) { | |
495 | WARN_ON_ONCE(!event->desc); | |
496 | if (!strncmp(event->desc->name, event_name, | |
497 | LTTNG_KERNEL_SYM_NAME_LEN - 1) | |
498 | && chan == event->chan) { | |
499 | ret = -EEXIST; | |
500 | goto exist; | |
abc0446a MD |
501 | } |
502 | } | |
3c997079 | 503 | |
11b5a3c2 | 504 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
abc0446a | 505 | if (!event) { |
4cf0bf51 | 506 | ret = -ENOMEM; |
4e3c1b9b | 507 | goto cache_error; |
abc0446a | 508 | } |
4e3c1b9b MD |
509 | event->chan = chan; |
510 | event->filter = filter; | |
e5382b6d | 511 | event->id = chan->free_event_id++; |
3c997079 MD |
512 | event->instrumentation = itype; |
513 | event->evtype = LTTNG_TYPE_EVENT; | |
514 | INIT_LIST_HEAD(&event->enablers_ref_head); | |
515 | ||
516 | switch (itype) { | |
ab2277d6 | 517 | case LTTNG_KERNEL_TRACEPOINT: |
3c997079 MD |
518 | /* Event will be enabled by enabler sync. */ |
519 | event->enabled = 0; | |
520 | event->registered = 0; | |
521 | event->desc = lttng_event_get(event_name); | |
abc0446a | 522 | if (!event->desc) { |
4cf0bf51 | 523 | ret = -ENOENT; |
d3dbe23c | 524 | goto register_error; |
abc0446a | 525 | } |
3c997079 MD |
526 | /* Populate lttng_event structure before event registration. */ |
527 | smp_wmb(); | |
baf20995 | 528 | break; |
ab2277d6 | 529 | case LTTNG_KERNEL_KPROBE: |
3c997079 MD |
530 | event->enabled = 1; |
531 | event->registered = 1; | |
532 | /* | |
533 | * Populate lttng_event structure before event | |
534 | * registration. | |
535 | */ | |
536 | smp_wmb(); | |
537 | ret = lttng_kprobes_register(event_name, | |
f17701fb MD |
538 | event_param->u.kprobe.symbol_name, |
539 | event_param->u.kprobe.offset, | |
540 | event_param->u.kprobe.addr, | |
541 | event); | |
abc0446a | 542 | if (ret) { |
4cf0bf51 | 543 | ret = -EINVAL; |
d6d808f3 | 544 | goto register_error; |
abc0446a | 545 | } |
edeb3137 MD |
546 | ret = try_module_get(event->desc->owner); |
547 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 548 | break; |
7371f44c MD |
549 | case LTTNG_KERNEL_KRETPROBE: |
550 | { | |
a90917c3 | 551 | struct lttng_event *event_return; |
7371f44c MD |
552 | |
553 | /* kretprobe defines 2 events */ | |
3c997079 MD |
554 | event->enabled = 1; |
555 | event->registered = 1; | |
7371f44c MD |
556 | event_return = |
557 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
abc0446a | 558 | if (!event_return) { |
4cf0bf51 | 559 | ret = -ENOMEM; |
7371f44c | 560 | goto register_error; |
abc0446a | 561 | } |
7371f44c MD |
562 | event_return->chan = chan; |
563 | event_return->filter = filter; | |
564 | event_return->id = chan->free_event_id++; | |
565 | event_return->enabled = 1; | |
3c997079 MD |
566 | event_return->registered = 1; |
567 | event_return->instrumentation = itype; | |
7371f44c | 568 | /* |
a90917c3 | 569 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
570 | */ |
571 | smp_wmb(); | |
3c997079 | 572 | ret = lttng_kretprobes_register(event_name, |
7371f44c MD |
573 | event_param->u.kretprobe.symbol_name, |
574 | event_param->u.kretprobe.offset, | |
575 | event_param->u.kretprobe.addr, | |
576 | event, event_return); | |
577 | if (ret) { | |
578 | kmem_cache_free(event_cache, event_return); | |
4cf0bf51 | 579 | ret = -EINVAL; |
7371f44c MD |
580 | goto register_error; |
581 | } | |
582 | /* Take 2 refs on the module: one per event. */ | |
583 | ret = try_module_get(event->desc->owner); | |
584 | WARN_ON_ONCE(!ret); | |
585 | ret = try_module_get(event->desc->owner); | |
586 | WARN_ON_ONCE(!ret); | |
a90917c3 | 587 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c | 588 | event_return); |
abc0446a | 589 | WARN_ON_ONCE(ret > 0); |
7371f44c MD |
590 | if (ret) { |
591 | kmem_cache_free(event_cache, event_return); | |
592 | module_put(event->desc->owner); | |
593 | module_put(event->desc->owner); | |
594 | goto statedump_error; | |
595 | } | |
596 | list_add(&event_return->list, &chan->session->events); | |
597 | break; | |
598 | } | |
ab2277d6 | 599 | case LTTNG_KERNEL_FUNCTION: |
3c997079 MD |
600 | event->enabled = 1; |
601 | event->registered = 1; | |
602 | /* | |
603 | * Populate lttng_event structure before event | |
604 | * registration. | |
605 | */ | |
606 | smp_wmb(); | |
607 | ret = lttng_ftrace_register(event_name, | |
e0a7a7c4 MD |
608 | event_param->u.ftrace.symbol_name, |
609 | event); | |
abc0446a | 610 | if (ret) { |
e0a7a7c4 | 611 | goto register_error; |
abc0446a | 612 | } |
edeb3137 MD |
613 | ret = try_module_get(event->desc->owner); |
614 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 615 | break; |
1ec65de1 | 616 | case LTTNG_KERNEL_NOOP: |
3c997079 MD |
617 | event->enabled = 1; |
618 | event->registered = 0; | |
619 | event->desc = event_desc; | |
abc0446a | 620 | if (!event->desc) { |
4cf0bf51 | 621 | ret = -EINVAL; |
259b6cb3 | 622 | goto register_error; |
abc0446a | 623 | } |
1ec65de1 | 624 | break; |
baf20995 MD |
625 | default: |
626 | WARN_ON_ONCE(1); | |
4cf0bf51 | 627 | ret = -EINVAL; |
df07930b | 628 | goto register_error; |
baf20995 | 629 | } |
a90917c3 | 630 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
abc0446a MD |
631 | WARN_ON_ONCE(ret > 0); |
632 | if (ret) { | |
c099397a | 633 | goto statedump_error; |
abc0446a | 634 | } |
3c997079 | 635 | hlist_add_head(&event->hlist, head); |
dda6a249 | 636 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 637 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
638 | return event; |
639 | ||
c099397a | 640 | statedump_error: |
259b6cb3 | 641 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 642 | register_error: |
11b5a3c2 | 643 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
644 | cache_error: |
645 | exist: | |
3c997079 | 646 | type_error: |
e5382b6d | 647 | full: |
4cf0bf51 | 648 | return ERR_PTR(ret); |
4e3c1b9b MD |
649 | } |
650 | ||
3c997079 MD |
651 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
652 | struct lttng_kernel_event *event_param, | |
653 | void *filter, | |
654 | const struct lttng_event_desc *event_desc, | |
655 | enum lttng_kernel_instrumentation itype) | |
656 | { | |
657 | struct lttng_event *event; | |
658 | ||
659 | mutex_lock(&sessions_mutex); | |
660 | event = _lttng_event_create(chan, event_param, filter, event_desc, | |
661 | itype); | |
662 | mutex_unlock(&sessions_mutex); | |
663 | return event; | |
664 | } | |
665 | ||
666 | /* Only used for tracepoints for now. */ | |
667 | static | |
668 | void register_event(struct lttng_event *event) | |
669 | { | |
670 | const struct lttng_event_desc *desc; | |
671 | int ret; | |
672 | ||
673 | WARN_ON_ONCE(event->instrumentation != LTTNG_KERNEL_TRACEPOINT); | |
674 | if (event->registered) | |
675 | return; | |
676 | desc = event->desc; | |
677 | ret = lttng_wrapper_tracepoint_probe_register(desc->kname, | |
678 | desc->probe_callback, event); | |
679 | if (!ret) | |
680 | event->registered = 1; | |
681 | } | |
682 | ||
4e3c1b9b MD |
683 | /* |
684 | * Only used internally at session destruction. | |
685 | */ | |
a90917c3 | 686 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 687 | { |
11b5a3c2 MD |
688 | int ret = -EINVAL; |
689 | ||
3c997079 MD |
690 | if (!event->registered) |
691 | return 0; | |
692 | ||
38d024ae | 693 | switch (event->instrumentation) { |
ab2277d6 | 694 | case LTTNG_KERNEL_TRACEPOINT: |
20591cf7 | 695 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
85a9ca7f | 696 | event->desc->probe_callback, |
11b5a3c2 MD |
697 | event); |
698 | if (ret) | |
699 | return ret; | |
baf20995 | 700 | break; |
ab2277d6 | 701 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 702 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
703 | ret = 0; |
704 | break; | |
7371f44c MD |
705 | case LTTNG_KERNEL_KRETPROBE: |
706 | lttng_kretprobes_unregister(event); | |
707 | ret = 0; | |
708 | break; | |
ab2277d6 | 709 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
710 | lttng_ftrace_unregister(event); |
711 | ret = 0; | |
712 | break; | |
259b6cb3 MD |
713 | case LTTNG_KERNEL_NOOP: |
714 | ret = 0; | |
715 | break; | |
baf20995 MD |
716 | default: |
717 | WARN_ON_ONCE(1); | |
718 | } | |
3c997079 MD |
719 | if (!ret) |
720 | event->registered = 0; | |
dda6a249 MD |
721 | return ret; |
722 | } | |
723 | ||
724 | /* | |
725 | * Only used internally at session destruction. | |
726 | */ | |
be066e6c | 727 | static |
a90917c3 | 728 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 729 | { |
edeb3137 MD |
730 | switch (event->instrumentation) { |
731 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 732 | lttng_event_put(event->desc); |
edeb3137 MD |
733 | break; |
734 | case LTTNG_KERNEL_KPROBE: | |
735 | module_put(event->desc->owner); | |
736 | lttng_kprobes_destroy_private(event); | |
737 | break; | |
7371f44c MD |
738 | case LTTNG_KERNEL_KRETPROBE: |
739 | module_put(event->desc->owner); | |
740 | lttng_kretprobes_destroy_private(event); | |
741 | break; | |
edeb3137 MD |
742 | case LTTNG_KERNEL_FUNCTION: |
743 | module_put(event->desc->owner); | |
744 | lttng_ftrace_destroy_private(event); | |
745 | break; | |
259b6cb3 MD |
746 | case LTTNG_KERNEL_NOOP: |
747 | break; | |
edeb3137 MD |
748 | default: |
749 | WARN_ON_ONCE(1); | |
750 | } | |
dda6a249 | 751 | list_del(&event->list); |
8070f5c0 | 752 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 753 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
754 | } |
755 | ||
e0130fab MD |
756 | int lttng_session_track_pid(struct lttng_session *session, int pid) |
757 | { | |
758 | int ret; | |
759 | ||
760 | if (pid < -1) | |
761 | return -EINVAL; | |
762 | mutex_lock(&sessions_mutex); | |
763 | if (pid == -1) { | |
764 | /* track all pids: destroy tracker. */ | |
765 | if (session->pid_tracker) { | |
766 | struct lttng_pid_tracker *lpf; | |
767 | ||
768 | lpf = session->pid_tracker; | |
769 | rcu_assign_pointer(session->pid_tracker, NULL); | |
770 | synchronize_trace(); | |
771 | lttng_pid_tracker_destroy(lpf); | |
772 | } | |
773 | ret = 0; | |
774 | } else { | |
775 | if (!session->pid_tracker) { | |
776 | struct lttng_pid_tracker *lpf; | |
777 | ||
778 | lpf = lttng_pid_tracker_create(); | |
779 | if (!lpf) { | |
780 | ret = -ENOMEM; | |
781 | goto unlock; | |
782 | } | |
783 | ret = lttng_pid_tracker_add(lpf, pid); | |
784 | rcu_assign_pointer(session->pid_tracker, lpf); | |
785 | } else { | |
786 | ret = lttng_pid_tracker_add(session->pid_tracker, pid); | |
787 | } | |
788 | } | |
789 | unlock: | |
790 | mutex_unlock(&sessions_mutex); | |
791 | return ret; | |
792 | } | |
793 | ||
794 | int lttng_session_untrack_pid(struct lttng_session *session, int pid) | |
795 | { | |
796 | int ret; | |
797 | ||
798 | if (pid < -1) | |
799 | return -EINVAL; | |
800 | mutex_lock(&sessions_mutex); | |
801 | if (pid == -1) { | |
802 | /* untrack all pids: replace by empty tracker. */ | |
803 | struct lttng_pid_tracker *old_lpf = session->pid_tracker; | |
804 | struct lttng_pid_tracker *lpf; | |
805 | ||
806 | lpf = lttng_pid_tracker_create(); | |
807 | if (!lpf) { | |
808 | ret = -ENOMEM; | |
809 | goto unlock; | |
810 | } | |
811 | rcu_assign_pointer(session->pid_tracker, lpf); | |
812 | synchronize_trace(); | |
813 | if (old_lpf) | |
814 | lttng_pid_tracker_destroy(old_lpf); | |
815 | ret = 0; | |
816 | } else { | |
817 | if (!session->pid_tracker) { | |
818 | ret = -ENOENT; | |
819 | goto unlock; | |
820 | } | |
821 | ret = lttng_pid_tracker_del(session->pid_tracker, pid); | |
822 | } | |
823 | unlock: | |
824 | mutex_unlock(&sessions_mutex); | |
825 | return ret; | |
826 | } | |
827 | ||
7e6f9ef6 MD |
828 | static |
829 | void *pid_list_start(struct seq_file *m, loff_t *pos) | |
830 | { | |
831 | struct lttng_session *session = m->private; | |
832 | struct lttng_pid_tracker *lpf; | |
833 | struct lttng_pid_hash_node *e; | |
834 | int iter = 0, i; | |
835 | ||
836 | mutex_lock(&sessions_mutex); | |
837 | lpf = session->pid_tracker; | |
838 | if (lpf) { | |
839 | for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) { | |
840 | struct hlist_head *head = &lpf->pid_hash[i]; | |
841 | ||
f934e302 | 842 | lttng_hlist_for_each_entry(e, head, hlist) { |
7e6f9ef6 MD |
843 | if (iter++ >= *pos) |
844 | return e; | |
845 | } | |
846 | } | |
847 | } else { | |
848 | /* PID tracker disabled. */ | |
849 | if (iter >= *pos && iter == 0) { | |
850 | return session; /* empty tracker */ | |
851 | } | |
852 | iter++; | |
853 | } | |
854 | /* End of list */ | |
855 | return NULL; | |
856 | } | |
857 | ||
858 | /* Called with sessions_mutex held. */ | |
859 | static | |
860 | void *pid_list_next(struct seq_file *m, void *p, loff_t *ppos) | |
861 | { | |
862 | struct lttng_session *session = m->private; | |
863 | struct lttng_pid_tracker *lpf; | |
864 | struct lttng_pid_hash_node *e; | |
865 | int iter = 0, i; | |
866 | ||
867 | (*ppos)++; | |
868 | lpf = session->pid_tracker; | |
869 | if (lpf) { | |
870 | for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) { | |
871 | struct hlist_head *head = &lpf->pid_hash[i]; | |
872 | ||
f934e302 | 873 | lttng_hlist_for_each_entry(e, head, hlist) { |
7e6f9ef6 MD |
874 | if (iter++ >= *ppos) |
875 | return e; | |
876 | } | |
877 | } | |
878 | } else { | |
879 | /* PID tracker disabled. */ | |
880 | if (iter >= *ppos && iter == 0) | |
881 | return session; /* empty tracker */ | |
882 | iter++; | |
883 | } | |
884 | ||
885 | /* End of list */ | |
886 | return NULL; | |
887 | } | |
888 | ||
889 | static | |
890 | void pid_list_stop(struct seq_file *m, void *p) | |
891 | { | |
892 | mutex_unlock(&sessions_mutex); | |
893 | } | |
894 | ||
895 | static | |
896 | int pid_list_show(struct seq_file *m, void *p) | |
897 | { | |
898 | int pid; | |
899 | ||
900 | if (p == m->private) { | |
901 | /* Tracker disabled. */ | |
902 | pid = -1; | |
903 | } else { | |
904 | const struct lttng_pid_hash_node *e = p; | |
905 | ||
906 | pid = lttng_pid_tracker_get_node_pid(e); | |
907 | } | |
908 | seq_printf(m, "process { pid = %d; };\n", pid); | |
909 | return 0; | |
910 | } | |
911 | ||
912 | static | |
913 | const struct seq_operations lttng_tracker_pids_list_seq_ops = { | |
914 | .start = pid_list_start, | |
915 | .next = pid_list_next, | |
916 | .stop = pid_list_stop, | |
917 | .show = pid_list_show, | |
918 | }; | |
919 | ||
920 | static | |
921 | int lttng_tracker_pids_list_open(struct inode *inode, struct file *file) | |
922 | { | |
923 | return seq_open(file, <tng_tracker_pids_list_seq_ops); | |
924 | } | |
925 | ||
926 | static | |
927 | int lttng_tracker_pids_list_release(struct inode *inode, struct file *file) | |
928 | { | |
929 | struct seq_file *m = file->private_data; | |
930 | struct lttng_session *session = m->private; | |
931 | int ret; | |
932 | ||
933 | WARN_ON_ONCE(!session); | |
934 | ret = seq_release(inode, file); | |
935 | if (!ret && session) | |
936 | fput(session->file); | |
937 | return ret; | |
938 | } | |
939 | ||
940 | const struct file_operations lttng_tracker_pids_list_fops = { | |
941 | .owner = THIS_MODULE, | |
942 | .open = lttng_tracker_pids_list_open, | |
943 | .read = seq_read, | |
944 | .llseek = seq_lseek, | |
945 | .release = lttng_tracker_pids_list_release, | |
946 | }; | |
947 | ||
948 | int lttng_session_list_tracker_pids(struct lttng_session *session) | |
949 | { | |
950 | struct file *tracker_pids_list_file; | |
951 | struct seq_file *m; | |
952 | int file_fd, ret; | |
953 | ||
954 | file_fd = lttng_get_unused_fd(); | |
955 | if (file_fd < 0) { | |
956 | ret = file_fd; | |
957 | goto fd_error; | |
958 | } | |
959 | ||
960 | tracker_pids_list_file = anon_inode_getfile("[lttng_tracker_pids_list]", | |
961 | <tng_tracker_pids_list_fops, | |
962 | NULL, O_RDWR); | |
963 | if (IS_ERR(tracker_pids_list_file)) { | |
964 | ret = PTR_ERR(tracker_pids_list_file); | |
965 | goto file_error; | |
966 | } | |
967 | ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file); | |
968 | if (ret < 0) | |
969 | goto open_error; | |
970 | m = tracker_pids_list_file->private_data; | |
971 | m->private = session; | |
972 | fd_install(file_fd, tracker_pids_list_file); | |
973 | atomic_long_inc(&session->file->f_count); | |
974 | ||
975 | return file_fd; | |
976 | ||
977 | open_error: | |
978 | fput(tracker_pids_list_file); | |
979 | file_error: | |
980 | put_unused_fd(file_fd); | |
981 | fd_error: | |
982 | return ret; | |
983 | } | |
984 | ||
3c997079 MD |
985 | /* |
986 | * Enabler management. | |
987 | */ | |
988 | static | |
989 | int lttng_desc_match_wildcard_enabler(const struct lttng_event_desc *desc, | |
990 | struct lttng_enabler *enabler) | |
991 | { | |
992 | WARN_ON_ONCE(enabler->type != LTTNG_ENABLER_WILDCARD); | |
993 | /* Compare excluding final '*' */ | |
994 | if (strncmp(desc->name, enabler->event_param.name, | |
995 | strlen(enabler->event_param.name) - 1)) | |
996 | return 0; | |
997 | return 1; | |
998 | } | |
999 | ||
1000 | static | |
1001 | int lttng_desc_match_name_enabler(const struct lttng_event_desc *desc, | |
1002 | struct lttng_enabler *enabler) | |
1003 | { | |
1004 | WARN_ON_ONCE(enabler->type != LTTNG_ENABLER_NAME); | |
1005 | if (strcmp(desc->name, enabler->event_param.name)) | |
1006 | return 0; | |
1007 | return 1; | |
1008 | } | |
1009 | ||
1010 | static | |
1011 | int lttng_desc_match_enabler(const struct lttng_event_desc *desc, | |
1012 | struct lttng_enabler *enabler) | |
1013 | { | |
1014 | switch (enabler->type) { | |
1015 | case LTTNG_ENABLER_WILDCARD: | |
1016 | return lttng_desc_match_wildcard_enabler(desc, enabler); | |
1017 | case LTTNG_ENABLER_NAME: | |
1018 | return lttng_desc_match_name_enabler(desc, enabler); | |
1019 | default: | |
1020 | return -EINVAL; | |
1021 | } | |
1022 | } | |
1023 | ||
1024 | static | |
1025 | int lttng_event_match_enabler(struct lttng_event *event, | |
1026 | struct lttng_enabler *enabler) | |
1027 | { | |
1028 | if (lttng_desc_match_enabler(event->desc, enabler) | |
1029 | && event->chan == enabler->chan) | |
1030 | return 1; | |
1031 | else | |
1032 | return 0; | |
1033 | } | |
1034 | ||
1035 | static | |
1036 | struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event, | |
1037 | struct lttng_enabler *enabler) | |
1038 | { | |
1039 | struct lttng_enabler_ref *enabler_ref; | |
1040 | ||
1041 | list_for_each_entry(enabler_ref, | |
1042 | &event->enablers_ref_head, node) { | |
1043 | if (enabler_ref->ref == enabler) | |
1044 | return enabler_ref; | |
1045 | } | |
1046 | return NULL; | |
1047 | } | |
1048 | ||
1049 | /* | |
1050 | * Create struct lttng_event if it is missing and present in the list of | |
1051 | * tracepoint probes. | |
1052 | * Should be called with sessions mutex held. | |
1053 | */ | |
1054 | static | |
1055 | void lttng_create_event_if_missing(struct lttng_enabler *enabler) | |
1056 | { | |
1057 | struct lttng_session *session = enabler->chan->session; | |
1058 | struct lttng_probe_desc *probe_desc; | |
1059 | const struct lttng_event_desc *desc; | |
1060 | int i; | |
1061 | struct list_head *probe_list; | |
1062 | ||
1063 | probe_list = lttng_get_probe_list_head(); | |
1064 | /* | |
1065 | * For each probe event, if we find that a probe event matches | |
1066 | * our enabler, create an associated lttng_event if not | |
1067 | * already present. | |
1068 | */ | |
1069 | list_for_each_entry(probe_desc, probe_list, head) { | |
1070 | for (i = 0; i < probe_desc->nr_events; i++) { | |
1071 | int found = 0; | |
1072 | struct hlist_head *head; | |
1073 | const char *event_name; | |
1074 | size_t name_len; | |
1075 | uint32_t hash; | |
1076 | struct lttng_event *event; | |
1077 | ||
1078 | desc = probe_desc->event_desc[i]; | |
1079 | if (!lttng_desc_match_enabler(desc, enabler)) | |
1080 | continue; | |
1081 | event_name = desc->name; | |
1082 | name_len = strlen(event_name); | |
1083 | ||
1084 | /* | |
1085 | * Check if already created. | |
1086 | */ | |
1087 | hash = jhash(event_name, name_len, 0); | |
1088 | head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; | |
1089 | hlist_for_each_entry(event, head, hlist) { | |
1090 | if (event->desc == desc | |
1091 | && event->chan == enabler->chan) | |
1092 | found = 1; | |
1093 | } | |
1094 | if (found) | |
1095 | continue; | |
1096 | ||
1097 | /* | |
1098 | * We need to create an event for this | |
1099 | * event probe. | |
1100 | */ | |
1101 | event = _lttng_event_create(enabler->chan, | |
1102 | NULL, NULL, desc, | |
1103 | LTTNG_KERNEL_TRACEPOINT); | |
1104 | if (!event) { | |
1105 | printk(KERN_INFO "Unable to create event %s\n", | |
1106 | probe_desc->event_desc[i]->name); | |
1107 | } | |
1108 | } | |
1109 | } | |
1110 | } | |
1111 | ||
1112 | /* | |
1113 | * Create events associated with an enabler (if not already present), | |
1114 | * and add backward reference from the event to the enabler. | |
1115 | * Should be called with sessions mutex held. | |
1116 | */ | |
1117 | static | |
1118 | int lttng_enabler_ref_events(struct lttng_enabler *enabler) | |
1119 | { | |
1120 | struct lttng_session *session = enabler->chan->session; | |
1121 | struct lttng_event *event; | |
1122 | ||
1123 | /* First ensure that probe events are created for this enabler. */ | |
1124 | lttng_create_event_if_missing(enabler); | |
1125 | ||
1126 | /* For each event matching enabler in session event list. */ | |
1127 | list_for_each_entry(event, &session->events, list) { | |
1128 | struct lttng_enabler_ref *enabler_ref; | |
1129 | ||
1130 | if (!lttng_event_match_enabler(event, enabler)) | |
1131 | continue; | |
1132 | enabler_ref = lttng_event_enabler_ref(event, enabler); | |
1133 | if (!enabler_ref) { | |
1134 | /* | |
1135 | * If no backward ref, create it. | |
1136 | * Add backward ref from event to enabler. | |
1137 | */ | |
1138 | enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL); | |
1139 | if (!enabler_ref) | |
1140 | return -ENOMEM; | |
1141 | enabler_ref->ref = enabler; | |
1142 | list_add(&enabler_ref->node, | |
1143 | &event->enablers_ref_head); | |
1144 | } | |
1145 | ||
1146 | /* TODO: merge event context. */ | |
1147 | } | |
1148 | return 0; | |
1149 | } | |
1150 | ||
1151 | /* | |
1152 | * Called at module load: connect the probe on all enablers matching | |
1153 | * this event. | |
1154 | * Called with sessions lock held. | |
1155 | */ | |
1156 | int lttng_fix_pending_events(void) | |
1157 | { | |
1158 | struct lttng_session *session; | |
1159 | ||
1160 | list_for_each_entry(session, &sessions, list) | |
1161 | lttng_session_lazy_sync_enablers(session); | |
1162 | return 0; | |
1163 | } | |
1164 | ||
1165 | struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, | |
1166 | struct lttng_kernel_event *event_param, | |
1167 | struct lttng_channel *chan) | |
1168 | { | |
1169 | struct lttng_enabler *enabler; | |
1170 | ||
1171 | enabler = kzalloc(sizeof(*enabler), GFP_KERNEL); | |
1172 | if (!enabler) | |
1173 | return NULL; | |
1174 | enabler->type = type; | |
1175 | memcpy(&enabler->event_param, event_param, | |
1176 | sizeof(enabler->event_param)); | |
1177 | enabler->chan = chan; | |
1178 | /* ctx left NULL */ | |
1179 | enabler->enabled = 1; | |
1180 | enabler->evtype = LTTNG_TYPE_ENABLER; | |
1181 | mutex_lock(&sessions_mutex); | |
1182 | list_add(&enabler->node, &enabler->chan->session->enablers_head); | |
1183 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
1184 | mutex_unlock(&sessions_mutex); | |
1185 | return enabler; | |
1186 | } | |
1187 | ||
1188 | int lttng_enabler_enable(struct lttng_enabler *enabler) | |
1189 | { | |
1190 | mutex_lock(&sessions_mutex); | |
1191 | enabler->enabled = 1; | |
1192 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
1193 | mutex_unlock(&sessions_mutex); | |
1194 | return 0; | |
1195 | } | |
1196 | ||
1197 | int lttng_enabler_disable(struct lttng_enabler *enabler) | |
1198 | { | |
1199 | mutex_lock(&sessions_mutex); | |
1200 | enabler->enabled = 0; | |
1201 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
1202 | mutex_unlock(&sessions_mutex); | |
1203 | return 0; | |
1204 | } | |
1205 | ||
1206 | int lttng_enabler_attach_context(struct lttng_enabler *enabler, | |
1207 | struct lttng_kernel_context *context_param) | |
1208 | { | |
1209 | return -ENOSYS; | |
1210 | } | |
1211 | ||
1212 | static | |
1213 | void lttng_enabler_destroy(struct lttng_enabler *enabler) | |
1214 | { | |
1215 | /* Destroy contexts */ | |
1216 | lttng_destroy_context(enabler->ctx); | |
1217 | ||
1218 | list_del(&enabler->node); | |
1219 | kfree(enabler); | |
1220 | } | |
1221 | ||
1222 | /* | |
1223 | * lttng_session_sync_enablers should be called just before starting a | |
1224 | * session. | |
1225 | * Should be called with sessions mutex held. | |
1226 | */ | |
1227 | static | |
1228 | void lttng_session_sync_enablers(struct lttng_session *session) | |
1229 | { | |
1230 | struct lttng_enabler *enabler; | |
1231 | struct lttng_event *event; | |
1232 | ||
1233 | list_for_each_entry(enabler, &session->enablers_head, node) | |
1234 | lttng_enabler_ref_events(enabler); | |
1235 | /* | |
1236 | * For each event, if at least one of its enablers is enabled, | |
1237 | * and its channel and session transient states are enabled, we | |
1238 | * enable the event, else we disable it. | |
1239 | */ | |
1240 | list_for_each_entry(event, &session->events, list) { | |
1241 | struct lttng_enabler_ref *enabler_ref; | |
1242 | int enabled = 0; | |
1243 | ||
1244 | if (event->instrumentation == LTTNG_KERNEL_TRACEPOINT) { | |
1245 | /* Enable events */ | |
1246 | list_for_each_entry(enabler_ref, | |
1247 | &event->enablers_ref_head, node) { | |
1248 | if (enabler_ref->ref->enabled) { | |
1249 | enabled = 1; | |
1250 | break; | |
1251 | } | |
1252 | } | |
1253 | } else { | |
1254 | /* Not handled with lazy sync. */ | |
1255 | continue; | |
1256 | } | |
1257 | /* | |
1258 | * Enabled state is based on union of enablers, with | |
1259 | * intesection of session and channel transient enable | |
1260 | * states. | |
1261 | */ | |
1262 | enabled = enabled && session->tstate && event->chan->tstate; | |
1263 | ||
1264 | ACCESS_ONCE(event->enabled) = enabled; | |
1265 | /* | |
1266 | * Sync tracepoint registration with event enabled | |
1267 | * state. | |
1268 | */ | |
1269 | if (enabled) { | |
1270 | register_event(event); | |
1271 | } else { | |
1272 | _lttng_event_unregister(event); | |
1273 | } | |
1274 | } | |
1275 | } | |
1276 | ||
1277 | /* | |
1278 | * Apply enablers to session events, adding events to session if need | |
1279 | * be. It is required after each modification applied to an active | |
1280 | * session, and right before session "start". | |
1281 | * "lazy" sync means we only sync if required. | |
1282 | * Should be called with sessions mutex held. | |
1283 | */ | |
1284 | static | |
1285 | void lttng_session_lazy_sync_enablers(struct lttng_session *session) | |
1286 | { | |
1287 | /* We can skip if session is not active */ | |
1288 | if (!session->active) | |
1289 | return; | |
1290 | lttng_session_sync_enablers(session); | |
1291 | } | |
1292 | ||
1ec3f75a | 1293 | /* |
d83004aa JD |
1294 | * Serialize at most one packet worth of metadata into a metadata |
1295 | * channel. | |
1ec3f75a MD |
1296 | * We have exclusive access to our metadata buffer (protected by the |
1297 | * sessions_mutex), so we can do racy operations such as looking for | |
1298 | * remaining space left in packet and write, since mutual exclusion | |
1299 | * protects us from concurrent writes. | |
35097f36 JD |
1300 | * Returns the number of bytes written in the channel, 0 if no data |
1301 | * was written and a negative value on error. | |
1ec3f75a | 1302 | */ |
b3b8072b MD |
1303 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
1304 | struct channel *chan) | |
d83004aa JD |
1305 | { |
1306 | struct lib_ring_buffer_ctx ctx; | |
1307 | int ret = 0; | |
1308 | size_t len, reserve_len; | |
1309 | ||
f613e3e6 MD |
1310 | /* |
1311 | * Ensure we support mutiple get_next / put sequences followed | |
de23d59d MD |
1312 | * by put_next. The metadata stream lock internally protects |
1313 | * reading the metadata cache. It can indeed be read | |
1314 | * concurrently by "get_next_subbuf" and "flush" operations on | |
1315 | * the buffer invoked by different processes. | |
f613e3e6 | 1316 | */ |
de23d59d | 1317 | mutex_lock(&stream->lock); |
f613e3e6 MD |
1318 | WARN_ON(stream->metadata_in < stream->metadata_out); |
1319 | if (stream->metadata_in != stream->metadata_out) | |
de23d59d | 1320 | goto end; |
f613e3e6 | 1321 | |
d83004aa | 1322 | len = stream->metadata_cache->metadata_written - |
f613e3e6 | 1323 | stream->metadata_in; |
9de2c215 | 1324 | if (!len) |
de23d59d | 1325 | goto end; |
d83004aa | 1326 | reserve_len = min_t(size_t, |
b3b8072b | 1327 | stream->transport->ops.packet_avail_size(chan), |
d83004aa | 1328 | len); |
b3b8072b | 1329 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
d83004aa JD |
1330 | sizeof(char), -1); |
1331 | /* | |
1332 | * If reservation failed, return an error to the caller. | |
1333 | */ | |
b3b8072b | 1334 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
d83004aa JD |
1335 | if (ret != 0) { |
1336 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); | |
1337 | goto end; | |
1338 | } | |
b3b8072b | 1339 | stream->transport->ops.event_write(&ctx, |
f613e3e6 | 1340 | stream->metadata_cache->data + stream->metadata_in, |
d83004aa | 1341 | reserve_len); |
b3b8072b | 1342 | stream->transport->ops.event_commit(&ctx); |
f613e3e6 | 1343 | stream->metadata_in += reserve_len; |
d83004aa JD |
1344 | ret = reserve_len; |
1345 | ||
1346 | end: | |
de23d59d | 1347 | mutex_unlock(&stream->lock); |
d83004aa JD |
1348 | return ret; |
1349 | } | |
1350 | ||
1351 | /* | |
1352 | * Write the metadata to the metadata cache. | |
1353 | * Must be called with sessions_mutex held. | |
1354 | */ | |
a90917c3 | 1355 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
1356 | const char *fmt, ...) |
1357 | { | |
c099397a | 1358 | char *str; |
d83004aa | 1359 | size_t len; |
c099397a | 1360 | va_list ap; |
d83004aa | 1361 | struct lttng_metadata_stream *stream; |
c099397a MD |
1362 | |
1363 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
1364 | ||
1365 | va_start(ap, fmt); | |
1366 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
1367 | va_end(ap); | |
1368 | if (!str) | |
1369 | return -ENOMEM; | |
1370 | ||
1ec3f75a | 1371 | len = strlen(str); |
d83004aa JD |
1372 | if (session->metadata_cache->metadata_written + len > |
1373 | session->metadata_cache->cache_alloc) { | |
1374 | char *tmp_cache_realloc; | |
1375 | unsigned int tmp_cache_alloc_size; | |
1376 | ||
1377 | tmp_cache_alloc_size = max_t(unsigned int, | |
1378 | session->metadata_cache->cache_alloc + len, | |
1379 | session->metadata_cache->cache_alloc << 1); | |
1380 | tmp_cache_realloc = krealloc(session->metadata_cache->data, | |
1381 | tmp_cache_alloc_size, GFP_KERNEL); | |
1382 | if (!tmp_cache_realloc) | |
1383 | goto err; | |
1384 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; | |
1385 | session->metadata_cache->data = tmp_cache_realloc; | |
c099397a | 1386 | } |
d83004aa JD |
1387 | memcpy(session->metadata_cache->data + |
1388 | session->metadata_cache->metadata_written, | |
1389 | str, len); | |
1390 | session->metadata_cache->metadata_written += len; | |
c099397a | 1391 | kfree(str); |
d83004aa JD |
1392 | |
1393 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) | |
1394 | wake_up_interruptible(&stream->read_wait); | |
1395 | ||
1396 | return 0; | |
1397 | ||
1398 | err: | |
1399 | kfree(str); | |
1400 | return -ENOMEM; | |
c099397a MD |
1401 | } |
1402 | ||
d83004aa JD |
1403 | /* |
1404 | * Must be called with sessions_mutex held. | |
1405 | */ | |
c099397a | 1406 | static |
a90917c3 | 1407 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 1408 | const struct lttng_event_field *field) |
c099397a | 1409 | { |
c099397a | 1410 | int ret = 0; |
c099397a | 1411 | |
8070f5c0 MD |
1412 | switch (field->type.atype) { |
1413 | case atype_integer: | |
1414 | ret = lttng_metadata_printf(session, | |
244465ab | 1415 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
1416 | field->type.u.basic.integer.size, |
1417 | field->type.u.basic.integer.alignment, | |
1418 | field->type.u.basic.integer.signedness, | |
1419 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
1420 | ? "none" | |
1421 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
1422 | ? "UTF8" | |
1423 | : "ASCII", | |
1424 | field->type.u.basic.integer.base, | |
c099397a | 1425 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1426 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 1427 | #else |
8070f5c0 | 1428 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 1429 | #endif |
8070f5c0 MD |
1430 | field->name); |
1431 | break; | |
1432 | case atype_enum: | |
1433 | ret = lttng_metadata_printf(session, | |
244465ab | 1434 | " %s _%s;\n", |
8070f5c0 MD |
1435 | field->type.u.basic.enumeration.name, |
1436 | field->name); | |
1437 | break; | |
1438 | case atype_array: | |
1439 | { | |
1440 | const struct lttng_basic_type *elem_type; | |
1441 | ||
1442 | elem_type = &field->type.u.array.elem_type; | |
1443 | ret = lttng_metadata_printf(session, | |
244465ab | 1444 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
1445 | elem_type->u.basic.integer.size, |
1446 | elem_type->u.basic.integer.alignment, | |
1447 | elem_type->u.basic.integer.signedness, | |
1448 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
1449 | ? "none" | |
1450 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
1451 | ? "UTF8" | |
1452 | : "ASCII", | |
1453 | elem_type->u.basic.integer.base, | |
8fa75f34 | 1454 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1455 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 1456 | #else |
8070f5c0 | 1457 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 1458 | #endif |
8070f5c0 MD |
1459 | field->name, field->type.u.array.length); |
1460 | break; | |
1461 | } | |
1462 | case atype_sequence: | |
1463 | { | |
1464 | const struct lttng_basic_type *elem_type; | |
1465 | const struct lttng_basic_type *length_type; | |
1466 | ||
1467 | elem_type = &field->type.u.sequence.elem_type; | |
1468 | length_type = &field->type.u.sequence.length_type; | |
1469 | ret = lttng_metadata_printf(session, | |
1470 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 1471 | length_type->u.basic.integer.size, |
32257272 | 1472 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
1473 | length_type->u.basic.integer.signedness, |
1474 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
1475 | ? "none" | |
0635cdd4 | 1476 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 1477 | ? "UTF8" |
0635cdd4 | 1478 | : "ASCII"), |
8070f5c0 | 1479 | length_type->u.basic.integer.base, |
e0a7a7c4 | 1480 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1481 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 1482 | #else |
0635cdd4 | 1483 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 1484 | #endif |
27d2368e MD |
1485 | field->name); |
1486 | if (ret) | |
1487 | return ret; | |
1488 | ||
1489 | ret = lttng_metadata_printf(session, | |
244465ab | 1490 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 1491 | elem_type->u.basic.integer.size, |
32257272 | 1492 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
1493 | elem_type->u.basic.integer.signedness, |
1494 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
1495 | ? "none" | |
0635cdd4 | 1496 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 1497 | ? "UTF8" |
0635cdd4 | 1498 | : "ASCII"), |
8070f5c0 | 1499 | elem_type->u.basic.integer.base, |
8fa75f34 | 1500 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1501 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 1502 | #else |
8070f5c0 | 1503 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 1504 | #endif |
8070f5c0 | 1505 | field->name, |
27d2368e | 1506 | field->name); |
8070f5c0 MD |
1507 | break; |
1508 | } | |
c099397a | 1509 | |
8070f5c0 MD |
1510 | case atype_string: |
1511 | /* Default encoding is UTF8 */ | |
1512 | ret = lttng_metadata_printf(session, | |
244465ab | 1513 | " string%s _%s;\n", |
8070f5c0 MD |
1514 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
1515 | " { encoding = ASCII; }" : "", | |
1516 | field->name); | |
1517 | break; | |
1518 | default: | |
1519 | WARN_ON_ONCE(1); | |
1520 | return -EINVAL; | |
1521 | } | |
1522 | return ret; | |
1523 | } | |
1524 | ||
1525 | static | |
a90917c3 | 1526 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
1527 | struct lttng_ctx *ctx) |
1528 | { | |
1529 | int ret = 0; | |
1530 | int i; | |
1531 | ||
1532 | if (!ctx) | |
1533 | return 0; | |
1534 | for (i = 0; i < ctx->nr_fields; i++) { | |
1535 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
1536 | ||
a90917c3 | 1537 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
1538 | if (ret) |
1539 | return ret; | |
1540 | } | |
1541 | return ret; | |
1542 | } | |
1543 | ||
1544 | static | |
a90917c3 MD |
1545 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
1546 | struct lttng_event *event) | |
8070f5c0 MD |
1547 | { |
1548 | const struct lttng_event_desc *desc = event->desc; | |
1549 | int ret = 0; | |
1550 | int i; | |
1551 | ||
1552 | for (i = 0; i < desc->nr_fields; i++) { | |
1553 | const struct lttng_event_field *field = &desc->fields[i]; | |
1554 | ||
a90917c3 | 1555 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
1556 | if (ret) |
1557 | return ret; | |
c099397a MD |
1558 | } |
1559 | return ret; | |
1560 | } | |
1561 | ||
d83004aa JD |
1562 | /* |
1563 | * Must be called with sessions_mutex held. | |
1564 | */ | |
c099397a | 1565 | static |
a90917c3 MD |
1566 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
1567 | struct lttng_channel *chan, | |
1568 | struct lttng_event *event) | |
c099397a MD |
1569 | { |
1570 | int ret = 0; | |
1571 | ||
1572 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
1573 | return 0; | |
d83004aa | 1574 | if (chan->channel_type == METADATA_CHANNEL) |
c099397a MD |
1575 | return 0; |
1576 | ||
1577 | ret = lttng_metadata_printf(session, | |
1578 | "event {\n" | |
ae734547 | 1579 | " name = \"%s\";\n" |
c099397a | 1580 | " id = %u;\n" |
b9074a1b | 1581 | " stream_id = %u;\n", |
c099397a MD |
1582 | event->desc->name, |
1583 | event->id, | |
1584 | event->chan->id); | |
1585 | if (ret) | |
1586 | goto end; | |
1587 | ||
b9074a1b MD |
1588 | if (event->ctx) { |
1589 | ret = lttng_metadata_printf(session, | |
1590 | " context := struct {\n"); | |
1591 | if (ret) | |
1592 | goto end; | |
1593 | } | |
a90917c3 | 1594 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
1595 | if (ret) |
1596 | goto end; | |
b9074a1b MD |
1597 | if (event->ctx) { |
1598 | ret = lttng_metadata_printf(session, | |
1599 | " };\n"); | |
1600 | if (ret) | |
1601 | goto end; | |
1602 | } | |
8070f5c0 MD |
1603 | |
1604 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
1605 | " fields := struct {\n" |
1606 | ); | |
1607 | if (ret) | |
1608 | goto end; | |
1609 | ||
a90917c3 | 1610 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
1611 | if (ret) |
1612 | goto end; | |
1613 | ||
1614 | /* | |
1615 | * LTTng space reservation can only reserve multiples of the | |
1616 | * byte size. | |
1617 | */ | |
1618 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1619 | " };\n" |
1620 | "};\n\n"); | |
c099397a MD |
1621 | if (ret) |
1622 | goto end; | |
1623 | ||
c099397a MD |
1624 | event->metadata_dumped = 1; |
1625 | end: | |
1626 | return ret; | |
1627 | ||
1628 | } | |
1629 | ||
d83004aa JD |
1630 | /* |
1631 | * Must be called with sessions_mutex held. | |
1632 | */ | |
c099397a | 1633 | static |
a90917c3 MD |
1634 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
1635 | struct lttng_channel *chan) | |
c099397a MD |
1636 | { |
1637 | int ret = 0; | |
1638 | ||
1639 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
1640 | return 0; | |
d83004aa JD |
1641 | |
1642 | if (chan->channel_type == METADATA_CHANNEL) | |
c099397a MD |
1643 | return 0; |
1644 | ||
1645 | WARN_ON_ONCE(!chan->header_type); | |
1646 | ret = lttng_metadata_printf(session, | |
1647 | "stream {\n" | |
1648 | " id = %u;\n" | |
9115fbdc | 1649 | " event.header := %s;\n" |
b9074a1b | 1650 | " packet.context := struct packet_context;\n", |
c099397a MD |
1651 | chan->id, |
1652 | chan->header_type == 1 ? "struct event_header_compact" : | |
1653 | "struct event_header_large"); | |
1654 | if (ret) | |
1655 | goto end; | |
1656 | ||
b9074a1b MD |
1657 | if (chan->ctx) { |
1658 | ret = lttng_metadata_printf(session, | |
1659 | " event.context := struct {\n"); | |
1660 | if (ret) | |
1661 | goto end; | |
1662 | } | |
a90917c3 | 1663 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
1664 | if (ret) |
1665 | goto end; | |
b9074a1b MD |
1666 | if (chan->ctx) { |
1667 | ret = lttng_metadata_printf(session, | |
1668 | " };\n"); | |
1669 | if (ret) | |
1670 | goto end; | |
1671 | } | |
8070f5c0 MD |
1672 | |
1673 | ret = lttng_metadata_printf(session, | |
b9074a1b | 1674 | "};\n\n"); |
8070f5c0 | 1675 | |
c099397a MD |
1676 | chan->metadata_dumped = 1; |
1677 | end: | |
1678 | return ret; | |
1679 | } | |
1680 | ||
d83004aa JD |
1681 | /* |
1682 | * Must be called with sessions_mutex held. | |
1683 | */ | |
9115fbdc | 1684 | static |
a90917c3 | 1685 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
1686 | { |
1687 | return lttng_metadata_printf(session, | |
1688 | "struct packet_context {\n" | |
a3ccff4f MD |
1689 | " uint64_clock_monotonic_t timestamp_begin;\n" |
1690 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
1691 | " uint64_t content_size;\n" |
1692 | " uint64_t packet_size;\n" | |
a9afe705 | 1693 | " unsigned long events_discarded;\n" |
9115fbdc | 1694 | " uint32_t cpu_id;\n" |
c6dfdf6f | 1695 | "};\n\n" |
9115fbdc MD |
1696 | ); |
1697 | } | |
1698 | ||
1699 | /* | |
1700 | * Compact header: | |
1701 | * id: range: 0 - 30. | |
1702 | * id 31 is reserved to indicate an extended header. | |
1703 | * | |
1704 | * Large header: | |
1705 | * id: range: 0 - 65534. | |
1706 | * id 65535 is reserved to indicate an extended header. | |
d83004aa JD |
1707 | * |
1708 | * Must be called with sessions_mutex held. | |
9115fbdc MD |
1709 | */ |
1710 | static | |
a90917c3 | 1711 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
1712 | { |
1713 | return lttng_metadata_printf(session, | |
1714 | "struct event_header_compact {\n" | |
1715 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
1716 | " variant <id> {\n" | |
1717 | " struct {\n" | |
a3ccff4f | 1718 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1719 | " } compact;\n" |
1720 | " struct {\n" | |
1721 | " uint32_t id;\n" | |
a3ccff4f | 1722 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1723 | " } extended;\n" |
1724 | " } v;\n" | |
1725 | "} align(%u);\n" | |
1726 | "\n" | |
1727 | "struct event_header_large {\n" | |
1728 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
1729 | " variant <id> {\n" | |
1730 | " struct {\n" | |
a3ccff4f | 1731 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1732 | " } compact;\n" |
1733 | " struct {\n" | |
1734 | " uint32_t id;\n" | |
a3ccff4f | 1735 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1736 | " } extended;\n" |
1737 | " } v;\n" | |
1738 | "} align(%u);\n\n", | |
a90917c3 MD |
1739 | lttng_alignof(uint32_t) * CHAR_BIT, |
1740 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
1741 | ); |
1742 | } | |
1743 | ||
a3ccff4f MD |
1744 | /* |
1745 | * Approximation of NTP time of day to clock monotonic correlation, | |
1746 | * taken at start of trace. | |
1747 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
1748 | * in future versions. | |
1749 | */ | |
1750 | static | |
1751 | uint64_t measure_clock_offset(void) | |
1752 | { | |
1753 | uint64_t offset, monotonic[2], realtime; | |
1754 | struct timespec rts = { 0, 0 }; | |
1755 | unsigned long flags; | |
1756 | ||
1757 | /* Disable interrupts to increase correlation precision. */ | |
1758 | local_irq_save(flags); | |
1759 | monotonic[0] = trace_clock_read64(); | |
1760 | getnstimeofday(&rts); | |
1761 | monotonic[1] = trace_clock_read64(); | |
1762 | local_irq_restore(flags); | |
1763 | ||
1764 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 1765 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
1766 | realtime += rts.tv_nsec; |
1767 | offset = realtime - offset; | |
1768 | return offset; | |
1769 | } | |
1770 | ||
c099397a MD |
1771 | /* |
1772 | * Output metadata into this session's metadata buffers. | |
d83004aa | 1773 | * Must be called with sessions_mutex held. |
c099397a MD |
1774 | */ |
1775 | static | |
a90917c3 | 1776 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 1777 | { |
30bdb6e4 | 1778 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 1779 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
1780 | struct lttng_channel *chan; |
1781 | struct lttng_event *event; | |
c099397a MD |
1782 | int ret = 0; |
1783 | ||
1784 | if (!ACCESS_ONCE(session->active)) | |
1785 | return 0; | |
1786 | if (session->metadata_dumped) | |
1787 | goto skip_session; | |
c099397a | 1788 | |
d793d5e1 | 1789 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
1790 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
1791 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
1792 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
1793 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
1794 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
1795 | |
1796 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1797 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
1798 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
1799 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
1800 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 1801 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
1802 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
1803 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
1804 | "\n" |
1805 | "trace {\n" | |
1806 | " major = %u;\n" | |
1807 | " minor = %u;\n" | |
30bdb6e4 | 1808 | " uuid = \"%s\";\n" |
d793d5e1 MD |
1809 | " byte_order = %s;\n" |
1810 | " packet.header := struct {\n" | |
1811 | " uint32_t magic;\n" | |
1ec3f75a | 1812 | " uint8_t uuid[16];\n" |
d793d5e1 | 1813 | " uint32_t stream_id;\n" |
0eb25f58 | 1814 | " };\n" |
d793d5e1 | 1815 | "};\n\n", |
a90917c3 MD |
1816 | lttng_alignof(uint8_t) * CHAR_BIT, |
1817 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1818 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1819 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
1820 | sizeof(unsigned long) * CHAR_BIT, |
1821 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
1822 | CTF_SPEC_MAJOR, |
1823 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
1824 | uuid_s, |
1825 | #ifdef __BIG_ENDIAN | |
1826 | "be" | |
1827 | #else | |
1828 | "le" | |
1829 | #endif | |
1830 | ); | |
1831 | if (ret) | |
1832 | goto end; | |
1833 | ||
99dc9597 MD |
1834 | ret = lttng_metadata_printf(session, |
1835 | "env {\n" | |
a6058143 | 1836 | " hostname = \"%s\";\n" |
c6c9e10f | 1837 | " domain = \"kernel\";\n" |
99dc9597 | 1838 | " sysname = \"%s\";\n" |
c6c9e10f MD |
1839 | " kernel_release = \"%s\";\n" |
1840 | " kernel_version = \"%s\";\n" | |
1841 | " tracer_name = \"lttng-modules\";\n" | |
1842 | " tracer_major = %d;\n" | |
1843 | " tracer_minor = %d;\n" | |
1844 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 1845 | "};\n\n", |
3d0d43db | 1846 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
1847 | utsname()->sysname, |
1848 | utsname()->release, | |
c6c9e10f MD |
1849 | utsname()->version, |
1850 | LTTNG_MODULES_MAJOR_VERSION, | |
1851 | LTTNG_MODULES_MINOR_VERSION, | |
1852 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
1853 | ); |
1854 | if (ret) | |
1855 | goto end; | |
1856 | ||
a3ccff4f MD |
1857 | ret = lttng_metadata_printf(session, |
1858 | "clock {\n" | |
a82c63f1 MD |
1859 | " name = %s;\n", |
1860 | "monotonic" | |
1861 | ); | |
1862 | if (ret) | |
1863 | goto end; | |
1864 | ||
1865 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1866 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1867 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1868 | clock_uuid_s |
1869 | ); | |
1870 | if (ret) | |
1871 | goto end; | |
1872 | } | |
1873 | ||
1874 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1875 | " description = \"Monotonic Clock\";\n" |
1876 | " freq = %llu; /* Frequency, in Hz */\n" | |
1877 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1878 | " offset = %llu;\n" | |
1879 | "};\n\n", | |
a3ccff4f MD |
1880 | (unsigned long long) trace_clock_freq(), |
1881 | (unsigned long long) measure_clock_offset() | |
1882 | ); | |
1883 | if (ret) | |
1884 | goto end; | |
1885 | ||
1886 | ret = lttng_metadata_printf(session, | |
1887 | "typealias integer {\n" | |
1888 | " size = 27; align = 1; signed = false;\n" | |
1889 | " map = clock.monotonic.value;\n" | |
1890 | "} := uint27_clock_monotonic_t;\n" | |
1891 | "\n" | |
1892 | "typealias integer {\n" | |
1893 | " size = 32; align = %u; signed = false;\n" | |
1894 | " map = clock.monotonic.value;\n" | |
1895 | "} := uint32_clock_monotonic_t;\n" | |
1896 | "\n" | |
1897 | "typealias integer {\n" | |
1898 | " size = 64; align = %u; signed = false;\n" | |
1899 | " map = clock.monotonic.value;\n" | |
1900 | "} := uint64_clock_monotonic_t;\n\n", | |
1901 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1902 | lttng_alignof(uint64_t) * CHAR_BIT | |
1903 | ); | |
1904 | if (ret) | |
1905 | goto end; | |
1906 | ||
a90917c3 | 1907 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1908 | if (ret) |
1909 | goto end; | |
1910 | ||
a90917c3 | 1911 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1912 | if (ret) |
1913 | goto end; | |
1914 | ||
c099397a MD |
1915 | skip_session: |
1916 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1917 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1918 | if (ret) |
1919 | goto end; | |
1920 | } | |
1921 | ||
1922 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1923 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1924 | if (ret) |
1925 | goto end; | |
1926 | } | |
1927 | session->metadata_dumped = 1; | |
1928 | end: | |
1929 | return ret; | |
1930 | } | |
1931 | ||
c0e31d2e | 1932 | /** |
a90917c3 | 1933 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1934 | * @transport: transport structure |
1935 | * | |
1936 | * Registers a transport which can be used as output to extract the data out of | |
1937 | * LTTng. The module calling this registration function must ensure that no | |
1938 | * trap-inducing code will be executed by the transport functions. E.g. | |
1939 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1940 | * is made visible to the transport function. This registration acts as a | |
1941 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1942 | * after its registration must it synchronize the TLBs. | |
1943 | */ | |
a90917c3 | 1944 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1945 | { |
1946 | /* | |
1947 | * Make sure no page fault can be triggered by the module about to be | |
1948 | * registered. We deal with this here so we don't have to call | |
1949 | * vmalloc_sync_all() in each module's init. | |
1950 | */ | |
6d2a620c | 1951 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1952 | |
1953 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1954 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1955 | mutex_unlock(&sessions_mutex); |
1956 | } | |
a90917c3 | 1957 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1958 | |
1959 | /** | |
a90917c3 | 1960 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1961 | * @transport: transport structure |
1962 | */ | |
a90917c3 | 1963 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1964 | { |
1965 | mutex_lock(&sessions_mutex); | |
1966 | list_del(&transport->node); | |
1967 | mutex_unlock(&sessions_mutex); | |
1968 | } | |
a90917c3 | 1969 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 1970 | |
a90917c3 | 1971 | static int __init lttng_events_init(void) |
4e3c1b9b | 1972 | { |
1c25284c MD |
1973 | int ret; |
1974 | ||
453b2495 JD |
1975 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
1976 | if (ret) | |
1977 | return ret; | |
1978 | ||
20591cf7 MD |
1979 | ret = lttng_tracepoint_init(); |
1980 | if (ret) | |
1981 | return ret; | |
a90917c3 | 1982 | event_cache = KMEM_CACHE(lttng_event, 0); |
20591cf7 MD |
1983 | if (!event_cache) { |
1984 | ret = -ENOMEM; | |
1985 | goto error_kmem; | |
1986 | } | |
80996790 | 1987 | ret = lttng_abi_init(); |
02119ee5 MD |
1988 | if (ret) |
1989 | goto error_abi; | |
0c956676 MD |
1990 | ret = lttng_logger_init(); |
1991 | if (ret) | |
1992 | goto error_logger; | |
4e3c1b9b | 1993 | return 0; |
0c956676 MD |
1994 | |
1995 | error_logger: | |
1996 | lttng_abi_exit(); | |
02119ee5 | 1997 | error_abi: |
1c25284c | 1998 | kmem_cache_destroy(event_cache); |
20591cf7 MD |
1999 | error_kmem: |
2000 | lttng_tracepoint_exit(); | |
1c25284c | 2001 | return ret; |
4e3c1b9b MD |
2002 | } |
2003 | ||
a90917c3 | 2004 | module_init(lttng_events_init); |
11b5a3c2 | 2005 | |
a90917c3 | 2006 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 2007 | { |
a90917c3 | 2008 | struct lttng_session *session, *tmpsession; |
92e94819 | 2009 | |
0c956676 | 2010 | lttng_logger_exit(); |
80996790 | 2011 | lttng_abi_exit(); |
92e94819 | 2012 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 2013 | lttng_session_destroy(session); |
11b5a3c2 | 2014 | kmem_cache_destroy(event_cache); |
20591cf7 | 2015 | lttng_tracepoint_exit(); |
4e3c1b9b | 2016 | } |
92e94819 | 2017 | |
a90917c3 | 2018 | module_exit(lttng_events_exit); |
11b5a3c2 | 2019 | |
92e94819 MD |
2020 | MODULE_LICENSE("GPL and additional rights"); |
2021 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
2022 | MODULE_DESCRIPTION("LTTng Events"); | |
9a9973ef MD |
2023 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
2024 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
309370e2 MD |
2025 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
2026 | LTTNG_MODULES_EXTRAVERSION); |