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: | |
33a39a3c | 484 | case LTTNG_KERNEL_SYSCALL: |
3c997079 MD |
485 | event_name = event_param->name; |
486 | break; | |
487 | default: | |
488 | WARN_ON_ONCE(1); | |
489 | ret = -EINVAL; | |
490 | goto type_error; | |
491 | } | |
492 | name_len = strlen(event_name); | |
493 | hash = jhash(event_name, name_len, 0); | |
494 | head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; | |
495 | hlist_for_each_entry(event, head, hlist) { | |
496 | WARN_ON_ONCE(!event->desc); | |
497 | if (!strncmp(event->desc->name, event_name, | |
498 | LTTNG_KERNEL_SYM_NAME_LEN - 1) | |
499 | && chan == event->chan) { | |
500 | ret = -EEXIST; | |
501 | goto exist; | |
abc0446a MD |
502 | } |
503 | } | |
3c997079 | 504 | |
11b5a3c2 | 505 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
abc0446a | 506 | if (!event) { |
4cf0bf51 | 507 | ret = -ENOMEM; |
4e3c1b9b | 508 | goto cache_error; |
abc0446a | 509 | } |
4e3c1b9b MD |
510 | event->chan = chan; |
511 | event->filter = filter; | |
e5382b6d | 512 | event->id = chan->free_event_id++; |
3c997079 MD |
513 | event->instrumentation = itype; |
514 | event->evtype = LTTNG_TYPE_EVENT; | |
515 | INIT_LIST_HEAD(&event->enablers_ref_head); | |
516 | ||
517 | switch (itype) { | |
ab2277d6 | 518 | case LTTNG_KERNEL_TRACEPOINT: |
3c997079 MD |
519 | /* Event will be enabled by enabler sync. */ |
520 | event->enabled = 0; | |
521 | event->registered = 0; | |
522 | event->desc = lttng_event_get(event_name); | |
abc0446a | 523 | if (!event->desc) { |
4cf0bf51 | 524 | ret = -ENOENT; |
d3dbe23c | 525 | goto register_error; |
abc0446a | 526 | } |
3c997079 MD |
527 | /* Populate lttng_event structure before event registration. */ |
528 | smp_wmb(); | |
baf20995 | 529 | break; |
ab2277d6 | 530 | case LTTNG_KERNEL_KPROBE: |
3c997079 MD |
531 | event->enabled = 1; |
532 | event->registered = 1; | |
533 | /* | |
534 | * Populate lttng_event structure before event | |
535 | * registration. | |
536 | */ | |
537 | smp_wmb(); | |
538 | ret = lttng_kprobes_register(event_name, | |
f17701fb MD |
539 | event_param->u.kprobe.symbol_name, |
540 | event_param->u.kprobe.offset, | |
541 | event_param->u.kprobe.addr, | |
542 | event); | |
abc0446a | 543 | if (ret) { |
4cf0bf51 | 544 | ret = -EINVAL; |
d6d808f3 | 545 | goto register_error; |
abc0446a | 546 | } |
edeb3137 MD |
547 | ret = try_module_get(event->desc->owner); |
548 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 549 | break; |
7371f44c MD |
550 | case LTTNG_KERNEL_KRETPROBE: |
551 | { | |
a90917c3 | 552 | struct lttng_event *event_return; |
7371f44c MD |
553 | |
554 | /* kretprobe defines 2 events */ | |
3c997079 MD |
555 | event->enabled = 1; |
556 | event->registered = 1; | |
7371f44c MD |
557 | event_return = |
558 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
abc0446a | 559 | if (!event_return) { |
4cf0bf51 | 560 | ret = -ENOMEM; |
7371f44c | 561 | goto register_error; |
abc0446a | 562 | } |
7371f44c MD |
563 | event_return->chan = chan; |
564 | event_return->filter = filter; | |
565 | event_return->id = chan->free_event_id++; | |
566 | event_return->enabled = 1; | |
3c997079 MD |
567 | event_return->registered = 1; |
568 | event_return->instrumentation = itype; | |
7371f44c | 569 | /* |
a90917c3 | 570 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
571 | */ |
572 | smp_wmb(); | |
3c997079 | 573 | ret = lttng_kretprobes_register(event_name, |
7371f44c MD |
574 | event_param->u.kretprobe.symbol_name, |
575 | event_param->u.kretprobe.offset, | |
576 | event_param->u.kretprobe.addr, | |
577 | event, event_return); | |
578 | if (ret) { | |
579 | kmem_cache_free(event_cache, event_return); | |
4cf0bf51 | 580 | ret = -EINVAL; |
7371f44c MD |
581 | goto register_error; |
582 | } | |
583 | /* Take 2 refs on the module: one per event. */ | |
584 | ret = try_module_get(event->desc->owner); | |
585 | WARN_ON_ONCE(!ret); | |
586 | ret = try_module_get(event->desc->owner); | |
587 | WARN_ON_ONCE(!ret); | |
a90917c3 | 588 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c | 589 | event_return); |
abc0446a | 590 | WARN_ON_ONCE(ret > 0); |
7371f44c MD |
591 | if (ret) { |
592 | kmem_cache_free(event_cache, event_return); | |
593 | module_put(event->desc->owner); | |
594 | module_put(event->desc->owner); | |
595 | goto statedump_error; | |
596 | } | |
597 | list_add(&event_return->list, &chan->session->events); | |
598 | break; | |
599 | } | |
ab2277d6 | 600 | case LTTNG_KERNEL_FUNCTION: |
3c997079 MD |
601 | event->enabled = 1; |
602 | event->registered = 1; | |
603 | /* | |
604 | * Populate lttng_event structure before event | |
605 | * registration. | |
606 | */ | |
607 | smp_wmb(); | |
608 | ret = lttng_ftrace_register(event_name, | |
e0a7a7c4 MD |
609 | event_param->u.ftrace.symbol_name, |
610 | event); | |
abc0446a | 611 | if (ret) { |
e0a7a7c4 | 612 | goto register_error; |
abc0446a | 613 | } |
edeb3137 MD |
614 | ret = try_module_get(event->desc->owner); |
615 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 616 | break; |
1ec65de1 | 617 | case LTTNG_KERNEL_NOOP: |
33a39a3c | 618 | case LTTNG_KERNEL_SYSCALL: |
3c997079 MD |
619 | event->enabled = 1; |
620 | event->registered = 0; | |
621 | event->desc = event_desc; | |
abc0446a | 622 | if (!event->desc) { |
4cf0bf51 | 623 | ret = -EINVAL; |
259b6cb3 | 624 | goto register_error; |
abc0446a | 625 | } |
1ec65de1 | 626 | break; |
baf20995 MD |
627 | default: |
628 | WARN_ON_ONCE(1); | |
4cf0bf51 | 629 | ret = -EINVAL; |
df07930b | 630 | goto register_error; |
baf20995 | 631 | } |
a90917c3 | 632 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
abc0446a MD |
633 | WARN_ON_ONCE(ret > 0); |
634 | if (ret) { | |
c099397a | 635 | goto statedump_error; |
abc0446a | 636 | } |
3c997079 | 637 | hlist_add_head(&event->hlist, head); |
dda6a249 | 638 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 639 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
640 | return event; |
641 | ||
c099397a | 642 | statedump_error: |
259b6cb3 | 643 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 644 | register_error: |
11b5a3c2 | 645 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
646 | cache_error: |
647 | exist: | |
3c997079 | 648 | type_error: |
e5382b6d | 649 | full: |
4cf0bf51 | 650 | return ERR_PTR(ret); |
4e3c1b9b MD |
651 | } |
652 | ||
3c997079 MD |
653 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
654 | struct lttng_kernel_event *event_param, | |
655 | void *filter, | |
656 | const struct lttng_event_desc *event_desc, | |
657 | enum lttng_kernel_instrumentation itype) | |
658 | { | |
659 | struct lttng_event *event; | |
660 | ||
661 | mutex_lock(&sessions_mutex); | |
662 | event = _lttng_event_create(chan, event_param, filter, event_desc, | |
663 | itype); | |
664 | mutex_unlock(&sessions_mutex); | |
665 | return event; | |
666 | } | |
667 | ||
668 | /* Only used for tracepoints for now. */ | |
669 | static | |
670 | void register_event(struct lttng_event *event) | |
671 | { | |
672 | const struct lttng_event_desc *desc; | |
673 | int ret; | |
674 | ||
675 | WARN_ON_ONCE(event->instrumentation != LTTNG_KERNEL_TRACEPOINT); | |
676 | if (event->registered) | |
677 | return; | |
678 | desc = event->desc; | |
679 | ret = lttng_wrapper_tracepoint_probe_register(desc->kname, | |
680 | desc->probe_callback, event); | |
681 | if (!ret) | |
682 | event->registered = 1; | |
683 | } | |
684 | ||
4e3c1b9b MD |
685 | /* |
686 | * Only used internally at session destruction. | |
687 | */ | |
a90917c3 | 688 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 689 | { |
11b5a3c2 MD |
690 | int ret = -EINVAL; |
691 | ||
3c997079 MD |
692 | if (!event->registered) |
693 | return 0; | |
694 | ||
38d024ae | 695 | switch (event->instrumentation) { |
ab2277d6 | 696 | case LTTNG_KERNEL_TRACEPOINT: |
20591cf7 | 697 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
85a9ca7f | 698 | event->desc->probe_callback, |
11b5a3c2 MD |
699 | event); |
700 | if (ret) | |
701 | return ret; | |
baf20995 | 702 | break; |
ab2277d6 | 703 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 704 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
705 | ret = 0; |
706 | break; | |
7371f44c MD |
707 | case LTTNG_KERNEL_KRETPROBE: |
708 | lttng_kretprobes_unregister(event); | |
709 | ret = 0; | |
710 | break; | |
ab2277d6 | 711 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
712 | lttng_ftrace_unregister(event); |
713 | ret = 0; | |
714 | break; | |
259b6cb3 | 715 | case LTTNG_KERNEL_NOOP: |
33a39a3c | 716 | case LTTNG_KERNEL_SYSCALL: |
259b6cb3 MD |
717 | ret = 0; |
718 | break; | |
baf20995 MD |
719 | default: |
720 | WARN_ON_ONCE(1); | |
721 | } | |
3c997079 MD |
722 | if (!ret) |
723 | event->registered = 0; | |
dda6a249 MD |
724 | return ret; |
725 | } | |
726 | ||
727 | /* | |
728 | * Only used internally at session destruction. | |
729 | */ | |
be066e6c | 730 | static |
a90917c3 | 731 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 732 | { |
edeb3137 MD |
733 | switch (event->instrumentation) { |
734 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 735 | lttng_event_put(event->desc); |
edeb3137 MD |
736 | break; |
737 | case LTTNG_KERNEL_KPROBE: | |
738 | module_put(event->desc->owner); | |
739 | lttng_kprobes_destroy_private(event); | |
740 | break; | |
7371f44c MD |
741 | case LTTNG_KERNEL_KRETPROBE: |
742 | module_put(event->desc->owner); | |
743 | lttng_kretprobes_destroy_private(event); | |
744 | break; | |
edeb3137 MD |
745 | case LTTNG_KERNEL_FUNCTION: |
746 | module_put(event->desc->owner); | |
747 | lttng_ftrace_destroy_private(event); | |
748 | break; | |
259b6cb3 | 749 | case LTTNG_KERNEL_NOOP: |
33a39a3c | 750 | case LTTNG_KERNEL_SYSCALL: |
259b6cb3 | 751 | break; |
edeb3137 MD |
752 | default: |
753 | WARN_ON_ONCE(1); | |
754 | } | |
dda6a249 | 755 | list_del(&event->list); |
8070f5c0 | 756 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 757 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
758 | } |
759 | ||
e0130fab MD |
760 | int lttng_session_track_pid(struct lttng_session *session, int pid) |
761 | { | |
762 | int ret; | |
763 | ||
764 | if (pid < -1) | |
765 | return -EINVAL; | |
766 | mutex_lock(&sessions_mutex); | |
767 | if (pid == -1) { | |
768 | /* track all pids: destroy tracker. */ | |
769 | if (session->pid_tracker) { | |
770 | struct lttng_pid_tracker *lpf; | |
771 | ||
772 | lpf = session->pid_tracker; | |
773 | rcu_assign_pointer(session->pid_tracker, NULL); | |
774 | synchronize_trace(); | |
775 | lttng_pid_tracker_destroy(lpf); | |
776 | } | |
777 | ret = 0; | |
778 | } else { | |
779 | if (!session->pid_tracker) { | |
780 | struct lttng_pid_tracker *lpf; | |
781 | ||
782 | lpf = lttng_pid_tracker_create(); | |
783 | if (!lpf) { | |
784 | ret = -ENOMEM; | |
785 | goto unlock; | |
786 | } | |
787 | ret = lttng_pid_tracker_add(lpf, pid); | |
788 | rcu_assign_pointer(session->pid_tracker, lpf); | |
789 | } else { | |
790 | ret = lttng_pid_tracker_add(session->pid_tracker, pid); | |
791 | } | |
792 | } | |
793 | unlock: | |
794 | mutex_unlock(&sessions_mutex); | |
795 | return ret; | |
796 | } | |
797 | ||
798 | int lttng_session_untrack_pid(struct lttng_session *session, int pid) | |
799 | { | |
800 | int ret; | |
801 | ||
802 | if (pid < -1) | |
803 | return -EINVAL; | |
804 | mutex_lock(&sessions_mutex); | |
805 | if (pid == -1) { | |
806 | /* untrack all pids: replace by empty tracker. */ | |
807 | struct lttng_pid_tracker *old_lpf = session->pid_tracker; | |
808 | struct lttng_pid_tracker *lpf; | |
809 | ||
810 | lpf = lttng_pid_tracker_create(); | |
811 | if (!lpf) { | |
812 | ret = -ENOMEM; | |
813 | goto unlock; | |
814 | } | |
815 | rcu_assign_pointer(session->pid_tracker, lpf); | |
816 | synchronize_trace(); | |
817 | if (old_lpf) | |
818 | lttng_pid_tracker_destroy(old_lpf); | |
819 | ret = 0; | |
820 | } else { | |
821 | if (!session->pid_tracker) { | |
822 | ret = -ENOENT; | |
823 | goto unlock; | |
824 | } | |
825 | ret = lttng_pid_tracker_del(session->pid_tracker, pid); | |
826 | } | |
827 | unlock: | |
828 | mutex_unlock(&sessions_mutex); | |
829 | return ret; | |
830 | } | |
831 | ||
7e6f9ef6 MD |
832 | static |
833 | void *pid_list_start(struct seq_file *m, loff_t *pos) | |
834 | { | |
835 | struct lttng_session *session = m->private; | |
836 | struct lttng_pid_tracker *lpf; | |
837 | struct lttng_pid_hash_node *e; | |
838 | int iter = 0, i; | |
839 | ||
840 | mutex_lock(&sessions_mutex); | |
841 | lpf = session->pid_tracker; | |
842 | if (lpf) { | |
843 | for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) { | |
844 | struct hlist_head *head = &lpf->pid_hash[i]; | |
845 | ||
f934e302 | 846 | lttng_hlist_for_each_entry(e, head, hlist) { |
7e6f9ef6 MD |
847 | if (iter++ >= *pos) |
848 | return e; | |
849 | } | |
850 | } | |
851 | } else { | |
852 | /* PID tracker disabled. */ | |
853 | if (iter >= *pos && iter == 0) { | |
854 | return session; /* empty tracker */ | |
855 | } | |
856 | iter++; | |
857 | } | |
858 | /* End of list */ | |
859 | return NULL; | |
860 | } | |
861 | ||
862 | /* Called with sessions_mutex held. */ | |
863 | static | |
864 | void *pid_list_next(struct seq_file *m, void *p, loff_t *ppos) | |
865 | { | |
866 | struct lttng_session *session = m->private; | |
867 | struct lttng_pid_tracker *lpf; | |
868 | struct lttng_pid_hash_node *e; | |
869 | int iter = 0, i; | |
870 | ||
871 | (*ppos)++; | |
872 | lpf = session->pid_tracker; | |
873 | if (lpf) { | |
874 | for (i = 0; i < LTTNG_PID_TABLE_SIZE; i++) { | |
875 | struct hlist_head *head = &lpf->pid_hash[i]; | |
876 | ||
f934e302 | 877 | lttng_hlist_for_each_entry(e, head, hlist) { |
7e6f9ef6 MD |
878 | if (iter++ >= *ppos) |
879 | return e; | |
880 | } | |
881 | } | |
882 | } else { | |
883 | /* PID tracker disabled. */ | |
884 | if (iter >= *ppos && iter == 0) | |
885 | return session; /* empty tracker */ | |
886 | iter++; | |
887 | } | |
888 | ||
889 | /* End of list */ | |
890 | return NULL; | |
891 | } | |
892 | ||
893 | static | |
894 | void pid_list_stop(struct seq_file *m, void *p) | |
895 | { | |
896 | mutex_unlock(&sessions_mutex); | |
897 | } | |
898 | ||
899 | static | |
900 | int pid_list_show(struct seq_file *m, void *p) | |
901 | { | |
902 | int pid; | |
903 | ||
904 | if (p == m->private) { | |
905 | /* Tracker disabled. */ | |
906 | pid = -1; | |
907 | } else { | |
908 | const struct lttng_pid_hash_node *e = p; | |
909 | ||
910 | pid = lttng_pid_tracker_get_node_pid(e); | |
911 | } | |
912 | seq_printf(m, "process { pid = %d; };\n", pid); | |
913 | return 0; | |
914 | } | |
915 | ||
916 | static | |
917 | const struct seq_operations lttng_tracker_pids_list_seq_ops = { | |
918 | .start = pid_list_start, | |
919 | .next = pid_list_next, | |
920 | .stop = pid_list_stop, | |
921 | .show = pid_list_show, | |
922 | }; | |
923 | ||
924 | static | |
925 | int lttng_tracker_pids_list_open(struct inode *inode, struct file *file) | |
926 | { | |
927 | return seq_open(file, <tng_tracker_pids_list_seq_ops); | |
928 | } | |
929 | ||
930 | static | |
931 | int lttng_tracker_pids_list_release(struct inode *inode, struct file *file) | |
932 | { | |
933 | struct seq_file *m = file->private_data; | |
934 | struct lttng_session *session = m->private; | |
935 | int ret; | |
936 | ||
937 | WARN_ON_ONCE(!session); | |
938 | ret = seq_release(inode, file); | |
939 | if (!ret && session) | |
940 | fput(session->file); | |
941 | return ret; | |
942 | } | |
943 | ||
944 | const struct file_operations lttng_tracker_pids_list_fops = { | |
945 | .owner = THIS_MODULE, | |
946 | .open = lttng_tracker_pids_list_open, | |
947 | .read = seq_read, | |
948 | .llseek = seq_lseek, | |
949 | .release = lttng_tracker_pids_list_release, | |
950 | }; | |
951 | ||
952 | int lttng_session_list_tracker_pids(struct lttng_session *session) | |
953 | { | |
954 | struct file *tracker_pids_list_file; | |
955 | struct seq_file *m; | |
956 | int file_fd, ret; | |
957 | ||
958 | file_fd = lttng_get_unused_fd(); | |
959 | if (file_fd < 0) { | |
960 | ret = file_fd; | |
961 | goto fd_error; | |
962 | } | |
963 | ||
964 | tracker_pids_list_file = anon_inode_getfile("[lttng_tracker_pids_list]", | |
965 | <tng_tracker_pids_list_fops, | |
966 | NULL, O_RDWR); | |
967 | if (IS_ERR(tracker_pids_list_file)) { | |
968 | ret = PTR_ERR(tracker_pids_list_file); | |
969 | goto file_error; | |
970 | } | |
971 | ret = lttng_tracker_pids_list_fops.open(NULL, tracker_pids_list_file); | |
972 | if (ret < 0) | |
973 | goto open_error; | |
974 | m = tracker_pids_list_file->private_data; | |
975 | m->private = session; | |
976 | fd_install(file_fd, tracker_pids_list_file); | |
977 | atomic_long_inc(&session->file->f_count); | |
978 | ||
979 | return file_fd; | |
980 | ||
981 | open_error: | |
982 | fput(tracker_pids_list_file); | |
983 | file_error: | |
984 | put_unused_fd(file_fd); | |
985 | fd_error: | |
986 | return ret; | |
987 | } | |
988 | ||
3c997079 MD |
989 | /* |
990 | * Enabler management. | |
991 | */ | |
992 | static | |
993 | int lttng_desc_match_wildcard_enabler(const struct lttng_event_desc *desc, | |
994 | struct lttng_enabler *enabler) | |
995 | { | |
996 | WARN_ON_ONCE(enabler->type != LTTNG_ENABLER_WILDCARD); | |
997 | /* Compare excluding final '*' */ | |
998 | if (strncmp(desc->name, enabler->event_param.name, | |
999 | strlen(enabler->event_param.name) - 1)) | |
1000 | return 0; | |
1001 | return 1; | |
1002 | } | |
1003 | ||
1004 | static | |
1005 | int lttng_desc_match_name_enabler(const struct lttng_event_desc *desc, | |
1006 | struct lttng_enabler *enabler) | |
1007 | { | |
1008 | WARN_ON_ONCE(enabler->type != LTTNG_ENABLER_NAME); | |
1009 | if (strcmp(desc->name, enabler->event_param.name)) | |
1010 | return 0; | |
1011 | return 1; | |
1012 | } | |
1013 | ||
1014 | static | |
1015 | int lttng_desc_match_enabler(const struct lttng_event_desc *desc, | |
1016 | struct lttng_enabler *enabler) | |
1017 | { | |
1018 | switch (enabler->type) { | |
1019 | case LTTNG_ENABLER_WILDCARD: | |
1020 | return lttng_desc_match_wildcard_enabler(desc, enabler); | |
1021 | case LTTNG_ENABLER_NAME: | |
1022 | return lttng_desc_match_name_enabler(desc, enabler); | |
1023 | default: | |
1024 | return -EINVAL; | |
1025 | } | |
1026 | } | |
1027 | ||
1028 | static | |
1029 | int lttng_event_match_enabler(struct lttng_event *event, | |
1030 | struct lttng_enabler *enabler) | |
1031 | { | |
33a39a3c MD |
1032 | if (enabler->event_param.instrumentation != event->instrumentation) |
1033 | return 0; | |
3c997079 MD |
1034 | if (lttng_desc_match_enabler(event->desc, enabler) |
1035 | && event->chan == enabler->chan) | |
1036 | return 1; | |
1037 | else | |
1038 | return 0; | |
1039 | } | |
1040 | ||
1041 | static | |
1042 | struct lttng_enabler_ref *lttng_event_enabler_ref(struct lttng_event *event, | |
1043 | struct lttng_enabler *enabler) | |
1044 | { | |
1045 | struct lttng_enabler_ref *enabler_ref; | |
1046 | ||
1047 | list_for_each_entry(enabler_ref, | |
1048 | &event->enablers_ref_head, node) { | |
1049 | if (enabler_ref->ref == enabler) | |
1050 | return enabler_ref; | |
1051 | } | |
1052 | return NULL; | |
1053 | } | |
1054 | ||
3c997079 | 1055 | static |
33a39a3c | 1056 | void lttng_create_tracepoint_if_missing(struct lttng_enabler *enabler) |
3c997079 MD |
1057 | { |
1058 | struct lttng_session *session = enabler->chan->session; | |
1059 | struct lttng_probe_desc *probe_desc; | |
1060 | const struct lttng_event_desc *desc; | |
1061 | int i; | |
1062 | struct list_head *probe_list; | |
1063 | ||
1064 | probe_list = lttng_get_probe_list_head(); | |
1065 | /* | |
1066 | * For each probe event, if we find that a probe event matches | |
1067 | * our enabler, create an associated lttng_event if not | |
1068 | * already present. | |
1069 | */ | |
1070 | list_for_each_entry(probe_desc, probe_list, head) { | |
1071 | for (i = 0; i < probe_desc->nr_events; i++) { | |
1072 | int found = 0; | |
1073 | struct hlist_head *head; | |
1074 | const char *event_name; | |
1075 | size_t name_len; | |
1076 | uint32_t hash; | |
1077 | struct lttng_event *event; | |
1078 | ||
1079 | desc = probe_desc->event_desc[i]; | |
1080 | if (!lttng_desc_match_enabler(desc, enabler)) | |
1081 | continue; | |
1082 | event_name = desc->name; | |
1083 | name_len = strlen(event_name); | |
1084 | ||
1085 | /* | |
1086 | * Check if already created. | |
1087 | */ | |
1088 | hash = jhash(event_name, name_len, 0); | |
1089 | head = &session->events_ht.table[hash & (LTTNG_EVENT_HT_SIZE - 1)]; | |
1090 | hlist_for_each_entry(event, head, hlist) { | |
1091 | if (event->desc == desc | |
1092 | && event->chan == enabler->chan) | |
1093 | found = 1; | |
1094 | } | |
1095 | if (found) | |
1096 | continue; | |
1097 | ||
1098 | /* | |
1099 | * We need to create an event for this | |
1100 | * event probe. | |
1101 | */ | |
1102 | event = _lttng_event_create(enabler->chan, | |
1103 | NULL, NULL, desc, | |
1104 | LTTNG_KERNEL_TRACEPOINT); | |
1105 | if (!event) { | |
1106 | printk(KERN_INFO "Unable to create event %s\n", | |
1107 | probe_desc->event_desc[i]->name); | |
1108 | } | |
1109 | } | |
1110 | } | |
1111 | } | |
1112 | ||
33a39a3c MD |
1113 | static |
1114 | void lttng_create_syscall_if_missing(struct lttng_enabler *enabler) | |
1115 | { | |
1116 | int ret; | |
1117 | ||
1118 | ret = lttng_syscalls_register(enabler->chan, NULL); | |
1119 | WARN_ON_ONCE(ret); | |
1120 | } | |
1121 | ||
1122 | /* | |
1123 | * Create struct lttng_event if it is missing and present in the list of | |
1124 | * tracepoint probes. | |
1125 | * Should be called with sessions mutex held. | |
1126 | */ | |
1127 | static | |
1128 | void lttng_create_event_if_missing(struct lttng_enabler *enabler) | |
1129 | { | |
1130 | switch (enabler->event_param.instrumentation) { | |
1131 | case LTTNG_KERNEL_TRACEPOINT: | |
1132 | lttng_create_tracepoint_if_missing(enabler); | |
1133 | break; | |
1134 | case LTTNG_KERNEL_SYSCALL: | |
1135 | lttng_create_syscall_if_missing(enabler); | |
1136 | break; | |
1137 | default: | |
1138 | WARN_ON_ONCE(1); | |
1139 | break; | |
1140 | } | |
1141 | } | |
1142 | ||
3c997079 MD |
1143 | /* |
1144 | * Create events associated with an enabler (if not already present), | |
1145 | * and add backward reference from the event to the enabler. | |
1146 | * Should be called with sessions mutex held. | |
1147 | */ | |
1148 | static | |
1149 | int lttng_enabler_ref_events(struct lttng_enabler *enabler) | |
1150 | { | |
1151 | struct lttng_session *session = enabler->chan->session; | |
1152 | struct lttng_event *event; | |
1153 | ||
1154 | /* First ensure that probe events are created for this enabler. */ | |
1155 | lttng_create_event_if_missing(enabler); | |
1156 | ||
1157 | /* For each event matching enabler in session event list. */ | |
1158 | list_for_each_entry(event, &session->events, list) { | |
1159 | struct lttng_enabler_ref *enabler_ref; | |
1160 | ||
1161 | if (!lttng_event_match_enabler(event, enabler)) | |
1162 | continue; | |
1163 | enabler_ref = lttng_event_enabler_ref(event, enabler); | |
1164 | if (!enabler_ref) { | |
1165 | /* | |
1166 | * If no backward ref, create it. | |
1167 | * Add backward ref from event to enabler. | |
1168 | */ | |
1169 | enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL); | |
1170 | if (!enabler_ref) | |
1171 | return -ENOMEM; | |
1172 | enabler_ref->ref = enabler; | |
1173 | list_add(&enabler_ref->node, | |
1174 | &event->enablers_ref_head); | |
1175 | } | |
1176 | ||
1177 | /* TODO: merge event context. */ | |
1178 | } | |
1179 | return 0; | |
1180 | } | |
1181 | ||
1182 | /* | |
1183 | * Called at module load: connect the probe on all enablers matching | |
1184 | * this event. | |
1185 | * Called with sessions lock held. | |
1186 | */ | |
1187 | int lttng_fix_pending_events(void) | |
1188 | { | |
1189 | struct lttng_session *session; | |
1190 | ||
1191 | list_for_each_entry(session, &sessions, list) | |
1192 | lttng_session_lazy_sync_enablers(session); | |
1193 | return 0; | |
1194 | } | |
1195 | ||
1196 | struct lttng_enabler *lttng_enabler_create(enum lttng_enabler_type type, | |
1197 | struct lttng_kernel_event *event_param, | |
1198 | struct lttng_channel *chan) | |
1199 | { | |
1200 | struct lttng_enabler *enabler; | |
1201 | ||
1202 | enabler = kzalloc(sizeof(*enabler), GFP_KERNEL); | |
1203 | if (!enabler) | |
1204 | return NULL; | |
1205 | enabler->type = type; | |
1206 | memcpy(&enabler->event_param, event_param, | |
1207 | sizeof(enabler->event_param)); | |
1208 | enabler->chan = chan; | |
1209 | /* ctx left NULL */ | |
1210 | enabler->enabled = 1; | |
1211 | enabler->evtype = LTTNG_TYPE_ENABLER; | |
1212 | mutex_lock(&sessions_mutex); | |
1213 | list_add(&enabler->node, &enabler->chan->session->enablers_head); | |
1214 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
1215 | mutex_unlock(&sessions_mutex); | |
1216 | return enabler; | |
1217 | } | |
1218 | ||
1219 | int lttng_enabler_enable(struct lttng_enabler *enabler) | |
1220 | { | |
1221 | mutex_lock(&sessions_mutex); | |
1222 | enabler->enabled = 1; | |
1223 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
1224 | mutex_unlock(&sessions_mutex); | |
1225 | return 0; | |
1226 | } | |
1227 | ||
1228 | int lttng_enabler_disable(struct lttng_enabler *enabler) | |
1229 | { | |
1230 | mutex_lock(&sessions_mutex); | |
1231 | enabler->enabled = 0; | |
1232 | lttng_session_lazy_sync_enablers(enabler->chan->session); | |
1233 | mutex_unlock(&sessions_mutex); | |
1234 | return 0; | |
1235 | } | |
1236 | ||
1237 | int lttng_enabler_attach_context(struct lttng_enabler *enabler, | |
1238 | struct lttng_kernel_context *context_param) | |
1239 | { | |
1240 | return -ENOSYS; | |
1241 | } | |
1242 | ||
1243 | static | |
1244 | void lttng_enabler_destroy(struct lttng_enabler *enabler) | |
1245 | { | |
1246 | /* Destroy contexts */ | |
1247 | lttng_destroy_context(enabler->ctx); | |
1248 | ||
1249 | list_del(&enabler->node); | |
1250 | kfree(enabler); | |
1251 | } | |
1252 | ||
1253 | /* | |
1254 | * lttng_session_sync_enablers should be called just before starting a | |
1255 | * session. | |
1256 | * Should be called with sessions mutex held. | |
1257 | */ | |
1258 | static | |
1259 | void lttng_session_sync_enablers(struct lttng_session *session) | |
1260 | { | |
1261 | struct lttng_enabler *enabler; | |
1262 | struct lttng_event *event; | |
1263 | ||
1264 | list_for_each_entry(enabler, &session->enablers_head, node) | |
1265 | lttng_enabler_ref_events(enabler); | |
1266 | /* | |
1267 | * For each event, if at least one of its enablers is enabled, | |
1268 | * and its channel and session transient states are enabled, we | |
1269 | * enable the event, else we disable it. | |
1270 | */ | |
1271 | list_for_each_entry(event, &session->events, list) { | |
1272 | struct lttng_enabler_ref *enabler_ref; | |
1273 | int enabled = 0; | |
1274 | ||
1275 | if (event->instrumentation == LTTNG_KERNEL_TRACEPOINT) { | |
1276 | /* Enable events */ | |
1277 | list_for_each_entry(enabler_ref, | |
1278 | &event->enablers_ref_head, node) { | |
1279 | if (enabler_ref->ref->enabled) { | |
1280 | enabled = 1; | |
1281 | break; | |
1282 | } | |
1283 | } | |
1284 | } else { | |
1285 | /* Not handled with lazy sync. */ | |
1286 | continue; | |
1287 | } | |
1288 | /* | |
1289 | * Enabled state is based on union of enablers, with | |
1290 | * intesection of session and channel transient enable | |
1291 | * states. | |
1292 | */ | |
1293 | enabled = enabled && session->tstate && event->chan->tstate; | |
1294 | ||
1295 | ACCESS_ONCE(event->enabled) = enabled; | |
1296 | /* | |
1297 | * Sync tracepoint registration with event enabled | |
1298 | * state. | |
1299 | */ | |
1300 | if (enabled) { | |
1301 | register_event(event); | |
1302 | } else { | |
1303 | _lttng_event_unregister(event); | |
1304 | } | |
1305 | } | |
1306 | } | |
1307 | ||
1308 | /* | |
1309 | * Apply enablers to session events, adding events to session if need | |
1310 | * be. It is required after each modification applied to an active | |
1311 | * session, and right before session "start". | |
1312 | * "lazy" sync means we only sync if required. | |
1313 | * Should be called with sessions mutex held. | |
1314 | */ | |
1315 | static | |
1316 | void lttng_session_lazy_sync_enablers(struct lttng_session *session) | |
1317 | { | |
1318 | /* We can skip if session is not active */ | |
1319 | if (!session->active) | |
1320 | return; | |
1321 | lttng_session_sync_enablers(session); | |
1322 | } | |
1323 | ||
1ec3f75a | 1324 | /* |
d83004aa JD |
1325 | * Serialize at most one packet worth of metadata into a metadata |
1326 | * channel. | |
1ec3f75a MD |
1327 | * We have exclusive access to our metadata buffer (protected by the |
1328 | * sessions_mutex), so we can do racy operations such as looking for | |
1329 | * remaining space left in packet and write, since mutual exclusion | |
1330 | * protects us from concurrent writes. | |
35097f36 JD |
1331 | * Returns the number of bytes written in the channel, 0 if no data |
1332 | * was written and a negative value on error. | |
1ec3f75a | 1333 | */ |
b3b8072b MD |
1334 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
1335 | struct channel *chan) | |
d83004aa JD |
1336 | { |
1337 | struct lib_ring_buffer_ctx ctx; | |
1338 | int ret = 0; | |
1339 | size_t len, reserve_len; | |
1340 | ||
f613e3e6 MD |
1341 | /* |
1342 | * Ensure we support mutiple get_next / put sequences followed | |
de23d59d MD |
1343 | * by put_next. The metadata stream lock internally protects |
1344 | * reading the metadata cache. It can indeed be read | |
1345 | * concurrently by "get_next_subbuf" and "flush" operations on | |
1346 | * the buffer invoked by different processes. | |
f613e3e6 | 1347 | */ |
de23d59d | 1348 | mutex_lock(&stream->lock); |
f613e3e6 MD |
1349 | WARN_ON(stream->metadata_in < stream->metadata_out); |
1350 | if (stream->metadata_in != stream->metadata_out) | |
de23d59d | 1351 | goto end; |
f613e3e6 | 1352 | |
d83004aa | 1353 | len = stream->metadata_cache->metadata_written - |
f613e3e6 | 1354 | stream->metadata_in; |
9de2c215 | 1355 | if (!len) |
de23d59d | 1356 | goto end; |
d83004aa | 1357 | reserve_len = min_t(size_t, |
b3b8072b | 1358 | stream->transport->ops.packet_avail_size(chan), |
d83004aa | 1359 | len); |
b3b8072b | 1360 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
d83004aa JD |
1361 | sizeof(char), -1); |
1362 | /* | |
1363 | * If reservation failed, return an error to the caller. | |
1364 | */ | |
b3b8072b | 1365 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
d83004aa JD |
1366 | if (ret != 0) { |
1367 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); | |
1368 | goto end; | |
1369 | } | |
b3b8072b | 1370 | stream->transport->ops.event_write(&ctx, |
f613e3e6 | 1371 | stream->metadata_cache->data + stream->metadata_in, |
d83004aa | 1372 | reserve_len); |
b3b8072b | 1373 | stream->transport->ops.event_commit(&ctx); |
f613e3e6 | 1374 | stream->metadata_in += reserve_len; |
d83004aa JD |
1375 | ret = reserve_len; |
1376 | ||
1377 | end: | |
de23d59d | 1378 | mutex_unlock(&stream->lock); |
d83004aa JD |
1379 | return ret; |
1380 | } | |
1381 | ||
1382 | /* | |
1383 | * Write the metadata to the metadata cache. | |
1384 | * Must be called with sessions_mutex held. | |
1385 | */ | |
a90917c3 | 1386 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
1387 | const char *fmt, ...) |
1388 | { | |
c099397a | 1389 | char *str; |
d83004aa | 1390 | size_t len; |
c099397a | 1391 | va_list ap; |
d83004aa | 1392 | struct lttng_metadata_stream *stream; |
c099397a MD |
1393 | |
1394 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
1395 | ||
1396 | va_start(ap, fmt); | |
1397 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
1398 | va_end(ap); | |
1399 | if (!str) | |
1400 | return -ENOMEM; | |
1401 | ||
1ec3f75a | 1402 | len = strlen(str); |
d83004aa JD |
1403 | if (session->metadata_cache->metadata_written + len > |
1404 | session->metadata_cache->cache_alloc) { | |
1405 | char *tmp_cache_realloc; | |
1406 | unsigned int tmp_cache_alloc_size; | |
1407 | ||
1408 | tmp_cache_alloc_size = max_t(unsigned int, | |
1409 | session->metadata_cache->cache_alloc + len, | |
1410 | session->metadata_cache->cache_alloc << 1); | |
1411 | tmp_cache_realloc = krealloc(session->metadata_cache->data, | |
1412 | tmp_cache_alloc_size, GFP_KERNEL); | |
1413 | if (!tmp_cache_realloc) | |
1414 | goto err; | |
1415 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; | |
1416 | session->metadata_cache->data = tmp_cache_realloc; | |
c099397a | 1417 | } |
d83004aa JD |
1418 | memcpy(session->metadata_cache->data + |
1419 | session->metadata_cache->metadata_written, | |
1420 | str, len); | |
1421 | session->metadata_cache->metadata_written += len; | |
c099397a | 1422 | kfree(str); |
d83004aa JD |
1423 | |
1424 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) | |
1425 | wake_up_interruptible(&stream->read_wait); | |
1426 | ||
1427 | return 0; | |
1428 | ||
1429 | err: | |
1430 | kfree(str); | |
1431 | return -ENOMEM; | |
c099397a MD |
1432 | } |
1433 | ||
d83004aa JD |
1434 | /* |
1435 | * Must be called with sessions_mutex held. | |
1436 | */ | |
c099397a | 1437 | static |
a90917c3 | 1438 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 1439 | const struct lttng_event_field *field) |
c099397a | 1440 | { |
c099397a | 1441 | int ret = 0; |
c099397a | 1442 | |
8070f5c0 MD |
1443 | switch (field->type.atype) { |
1444 | case atype_integer: | |
1445 | ret = lttng_metadata_printf(session, | |
244465ab | 1446 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
1447 | field->type.u.basic.integer.size, |
1448 | field->type.u.basic.integer.alignment, | |
1449 | field->type.u.basic.integer.signedness, | |
1450 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
1451 | ? "none" | |
1452 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
1453 | ? "UTF8" | |
1454 | : "ASCII", | |
1455 | field->type.u.basic.integer.base, | |
c099397a | 1456 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1457 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 1458 | #else |
8070f5c0 | 1459 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 1460 | #endif |
8070f5c0 MD |
1461 | field->name); |
1462 | break; | |
1463 | case atype_enum: | |
1464 | ret = lttng_metadata_printf(session, | |
244465ab | 1465 | " %s _%s;\n", |
8070f5c0 MD |
1466 | field->type.u.basic.enumeration.name, |
1467 | field->name); | |
1468 | break; | |
1469 | case atype_array: | |
1470 | { | |
1471 | const struct lttng_basic_type *elem_type; | |
1472 | ||
1473 | elem_type = &field->type.u.array.elem_type; | |
1474 | ret = lttng_metadata_printf(session, | |
244465ab | 1475 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
1476 | elem_type->u.basic.integer.size, |
1477 | elem_type->u.basic.integer.alignment, | |
1478 | elem_type->u.basic.integer.signedness, | |
1479 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
1480 | ? "none" | |
1481 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
1482 | ? "UTF8" | |
1483 | : "ASCII", | |
1484 | elem_type->u.basic.integer.base, | |
8fa75f34 | 1485 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1486 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 1487 | #else |
8070f5c0 | 1488 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 1489 | #endif |
8070f5c0 MD |
1490 | field->name, field->type.u.array.length); |
1491 | break; | |
1492 | } | |
1493 | case atype_sequence: | |
1494 | { | |
1495 | const struct lttng_basic_type *elem_type; | |
1496 | const struct lttng_basic_type *length_type; | |
1497 | ||
1498 | elem_type = &field->type.u.sequence.elem_type; | |
1499 | length_type = &field->type.u.sequence.length_type; | |
1500 | ret = lttng_metadata_printf(session, | |
1501 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 1502 | length_type->u.basic.integer.size, |
32257272 | 1503 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
1504 | length_type->u.basic.integer.signedness, |
1505 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
1506 | ? "none" | |
0635cdd4 | 1507 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 1508 | ? "UTF8" |
0635cdd4 | 1509 | : "ASCII"), |
8070f5c0 | 1510 | length_type->u.basic.integer.base, |
e0a7a7c4 | 1511 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1512 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 1513 | #else |
0635cdd4 | 1514 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 1515 | #endif |
27d2368e MD |
1516 | field->name); |
1517 | if (ret) | |
1518 | return ret; | |
1519 | ||
1520 | ret = lttng_metadata_printf(session, | |
244465ab | 1521 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 1522 | elem_type->u.basic.integer.size, |
32257272 | 1523 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
1524 | elem_type->u.basic.integer.signedness, |
1525 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
1526 | ? "none" | |
0635cdd4 | 1527 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 1528 | ? "UTF8" |
0635cdd4 | 1529 | : "ASCII"), |
8070f5c0 | 1530 | elem_type->u.basic.integer.base, |
8fa75f34 | 1531 | #ifdef __BIG_ENDIAN |
8070f5c0 | 1532 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 1533 | #else |
8070f5c0 | 1534 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 1535 | #endif |
8070f5c0 | 1536 | field->name, |
27d2368e | 1537 | field->name); |
8070f5c0 MD |
1538 | break; |
1539 | } | |
c099397a | 1540 | |
8070f5c0 MD |
1541 | case atype_string: |
1542 | /* Default encoding is UTF8 */ | |
1543 | ret = lttng_metadata_printf(session, | |
244465ab | 1544 | " string%s _%s;\n", |
8070f5c0 MD |
1545 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
1546 | " { encoding = ASCII; }" : "", | |
1547 | field->name); | |
1548 | break; | |
1549 | default: | |
1550 | WARN_ON_ONCE(1); | |
1551 | return -EINVAL; | |
1552 | } | |
1553 | return ret; | |
1554 | } | |
1555 | ||
1556 | static | |
a90917c3 | 1557 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
1558 | struct lttng_ctx *ctx) |
1559 | { | |
1560 | int ret = 0; | |
1561 | int i; | |
1562 | ||
1563 | if (!ctx) | |
1564 | return 0; | |
1565 | for (i = 0; i < ctx->nr_fields; i++) { | |
1566 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
1567 | ||
a90917c3 | 1568 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
1569 | if (ret) |
1570 | return ret; | |
1571 | } | |
1572 | return ret; | |
1573 | } | |
1574 | ||
1575 | static | |
a90917c3 MD |
1576 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
1577 | struct lttng_event *event) | |
8070f5c0 MD |
1578 | { |
1579 | const struct lttng_event_desc *desc = event->desc; | |
1580 | int ret = 0; | |
1581 | int i; | |
1582 | ||
1583 | for (i = 0; i < desc->nr_fields; i++) { | |
1584 | const struct lttng_event_field *field = &desc->fields[i]; | |
1585 | ||
a90917c3 | 1586 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
1587 | if (ret) |
1588 | return ret; | |
c099397a MD |
1589 | } |
1590 | return ret; | |
1591 | } | |
1592 | ||
d83004aa JD |
1593 | /* |
1594 | * Must be called with sessions_mutex held. | |
1595 | */ | |
c099397a | 1596 | static |
a90917c3 MD |
1597 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
1598 | struct lttng_channel *chan, | |
1599 | struct lttng_event *event) | |
c099397a MD |
1600 | { |
1601 | int ret = 0; | |
1602 | ||
1603 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
1604 | return 0; | |
d83004aa | 1605 | if (chan->channel_type == METADATA_CHANNEL) |
c099397a MD |
1606 | return 0; |
1607 | ||
1608 | ret = lttng_metadata_printf(session, | |
1609 | "event {\n" | |
ae734547 | 1610 | " name = \"%s\";\n" |
c099397a | 1611 | " id = %u;\n" |
b9074a1b | 1612 | " stream_id = %u;\n", |
c099397a MD |
1613 | event->desc->name, |
1614 | event->id, | |
1615 | event->chan->id); | |
1616 | if (ret) | |
1617 | goto end; | |
1618 | ||
b9074a1b MD |
1619 | if (event->ctx) { |
1620 | ret = lttng_metadata_printf(session, | |
1621 | " context := struct {\n"); | |
1622 | if (ret) | |
1623 | goto end; | |
1624 | } | |
a90917c3 | 1625 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
1626 | if (ret) |
1627 | goto end; | |
b9074a1b MD |
1628 | if (event->ctx) { |
1629 | ret = lttng_metadata_printf(session, | |
1630 | " };\n"); | |
1631 | if (ret) | |
1632 | goto end; | |
1633 | } | |
8070f5c0 MD |
1634 | |
1635 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
1636 | " fields := struct {\n" |
1637 | ); | |
1638 | if (ret) | |
1639 | goto end; | |
1640 | ||
a90917c3 | 1641 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
1642 | if (ret) |
1643 | goto end; | |
1644 | ||
1645 | /* | |
1646 | * LTTng space reservation can only reserve multiples of the | |
1647 | * byte size. | |
1648 | */ | |
1649 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1650 | " };\n" |
1651 | "};\n\n"); | |
c099397a MD |
1652 | if (ret) |
1653 | goto end; | |
1654 | ||
c099397a MD |
1655 | event->metadata_dumped = 1; |
1656 | end: | |
1657 | return ret; | |
1658 | ||
1659 | } | |
1660 | ||
d83004aa JD |
1661 | /* |
1662 | * Must be called with sessions_mutex held. | |
1663 | */ | |
c099397a | 1664 | static |
a90917c3 MD |
1665 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
1666 | struct lttng_channel *chan) | |
c099397a MD |
1667 | { |
1668 | int ret = 0; | |
1669 | ||
1670 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
1671 | return 0; | |
d83004aa JD |
1672 | |
1673 | if (chan->channel_type == METADATA_CHANNEL) | |
c099397a MD |
1674 | return 0; |
1675 | ||
1676 | WARN_ON_ONCE(!chan->header_type); | |
1677 | ret = lttng_metadata_printf(session, | |
1678 | "stream {\n" | |
1679 | " id = %u;\n" | |
9115fbdc | 1680 | " event.header := %s;\n" |
b9074a1b | 1681 | " packet.context := struct packet_context;\n", |
c099397a MD |
1682 | chan->id, |
1683 | chan->header_type == 1 ? "struct event_header_compact" : | |
1684 | "struct event_header_large"); | |
1685 | if (ret) | |
1686 | goto end; | |
1687 | ||
b9074a1b MD |
1688 | if (chan->ctx) { |
1689 | ret = lttng_metadata_printf(session, | |
1690 | " event.context := struct {\n"); | |
1691 | if (ret) | |
1692 | goto end; | |
1693 | } | |
a90917c3 | 1694 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
1695 | if (ret) |
1696 | goto end; | |
b9074a1b MD |
1697 | if (chan->ctx) { |
1698 | ret = lttng_metadata_printf(session, | |
1699 | " };\n"); | |
1700 | if (ret) | |
1701 | goto end; | |
1702 | } | |
8070f5c0 MD |
1703 | |
1704 | ret = lttng_metadata_printf(session, | |
b9074a1b | 1705 | "};\n\n"); |
8070f5c0 | 1706 | |
c099397a MD |
1707 | chan->metadata_dumped = 1; |
1708 | end: | |
1709 | return ret; | |
1710 | } | |
1711 | ||
d83004aa JD |
1712 | /* |
1713 | * Must be called with sessions_mutex held. | |
1714 | */ | |
9115fbdc | 1715 | static |
a90917c3 | 1716 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
1717 | { |
1718 | return lttng_metadata_printf(session, | |
1719 | "struct packet_context {\n" | |
a3ccff4f MD |
1720 | " uint64_clock_monotonic_t timestamp_begin;\n" |
1721 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
1722 | " uint64_t content_size;\n" |
1723 | " uint64_t packet_size;\n" | |
a9afe705 | 1724 | " unsigned long events_discarded;\n" |
9115fbdc | 1725 | " uint32_t cpu_id;\n" |
c6dfdf6f | 1726 | "};\n\n" |
9115fbdc MD |
1727 | ); |
1728 | } | |
1729 | ||
1730 | /* | |
1731 | * Compact header: | |
1732 | * id: range: 0 - 30. | |
1733 | * id 31 is reserved to indicate an extended header. | |
1734 | * | |
1735 | * Large header: | |
1736 | * id: range: 0 - 65534. | |
1737 | * id 65535 is reserved to indicate an extended header. | |
d83004aa JD |
1738 | * |
1739 | * Must be called with sessions_mutex held. | |
9115fbdc MD |
1740 | */ |
1741 | static | |
a90917c3 | 1742 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
1743 | { |
1744 | return lttng_metadata_printf(session, | |
1745 | "struct event_header_compact {\n" | |
1746 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
1747 | " variant <id> {\n" | |
1748 | " struct {\n" | |
a3ccff4f | 1749 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1750 | " } compact;\n" |
1751 | " struct {\n" | |
1752 | " uint32_t id;\n" | |
a3ccff4f | 1753 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1754 | " } extended;\n" |
1755 | " } v;\n" | |
1756 | "} align(%u);\n" | |
1757 | "\n" | |
1758 | "struct event_header_large {\n" | |
1759 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
1760 | " variant <id> {\n" | |
1761 | " struct {\n" | |
a3ccff4f | 1762 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1763 | " } compact;\n" |
1764 | " struct {\n" | |
1765 | " uint32_t id;\n" | |
a3ccff4f | 1766 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1767 | " } extended;\n" |
1768 | " } v;\n" | |
1769 | "} align(%u);\n\n", | |
a90917c3 MD |
1770 | lttng_alignof(uint32_t) * CHAR_BIT, |
1771 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
1772 | ); |
1773 | } | |
1774 | ||
a3ccff4f MD |
1775 | /* |
1776 | * Approximation of NTP time of day to clock monotonic correlation, | |
1777 | * taken at start of trace. | |
1778 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
1779 | * in future versions. | |
1780 | */ | |
1781 | static | |
1782 | uint64_t measure_clock_offset(void) | |
1783 | { | |
1784 | uint64_t offset, monotonic[2], realtime; | |
1785 | struct timespec rts = { 0, 0 }; | |
1786 | unsigned long flags; | |
1787 | ||
1788 | /* Disable interrupts to increase correlation precision. */ | |
1789 | local_irq_save(flags); | |
1790 | monotonic[0] = trace_clock_read64(); | |
1791 | getnstimeofday(&rts); | |
1792 | monotonic[1] = trace_clock_read64(); | |
1793 | local_irq_restore(flags); | |
1794 | ||
1795 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 1796 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
1797 | realtime += rts.tv_nsec; |
1798 | offset = realtime - offset; | |
1799 | return offset; | |
1800 | } | |
1801 | ||
c099397a MD |
1802 | /* |
1803 | * Output metadata into this session's metadata buffers. | |
d83004aa | 1804 | * Must be called with sessions_mutex held. |
c099397a MD |
1805 | */ |
1806 | static | |
a90917c3 | 1807 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 1808 | { |
30bdb6e4 | 1809 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 1810 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
1811 | struct lttng_channel *chan; |
1812 | struct lttng_event *event; | |
c099397a MD |
1813 | int ret = 0; |
1814 | ||
1815 | if (!ACCESS_ONCE(session->active)) | |
1816 | return 0; | |
1817 | if (session->metadata_dumped) | |
1818 | goto skip_session; | |
c099397a | 1819 | |
d793d5e1 | 1820 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
1821 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
1822 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
1823 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
1824 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
1825 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
1826 | |
1827 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1828 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
1829 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
1830 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
1831 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 1832 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
1833 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
1834 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
1835 | "\n" |
1836 | "trace {\n" | |
1837 | " major = %u;\n" | |
1838 | " minor = %u;\n" | |
30bdb6e4 | 1839 | " uuid = \"%s\";\n" |
d793d5e1 MD |
1840 | " byte_order = %s;\n" |
1841 | " packet.header := struct {\n" | |
1842 | " uint32_t magic;\n" | |
1ec3f75a | 1843 | " uint8_t uuid[16];\n" |
d793d5e1 | 1844 | " uint32_t stream_id;\n" |
0eb25f58 | 1845 | " };\n" |
d793d5e1 | 1846 | "};\n\n", |
a90917c3 MD |
1847 | lttng_alignof(uint8_t) * CHAR_BIT, |
1848 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1849 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1850 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
1851 | sizeof(unsigned long) * CHAR_BIT, |
1852 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
1853 | CTF_SPEC_MAJOR, |
1854 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
1855 | uuid_s, |
1856 | #ifdef __BIG_ENDIAN | |
1857 | "be" | |
1858 | #else | |
1859 | "le" | |
1860 | #endif | |
1861 | ); | |
1862 | if (ret) | |
1863 | goto end; | |
1864 | ||
99dc9597 MD |
1865 | ret = lttng_metadata_printf(session, |
1866 | "env {\n" | |
a6058143 | 1867 | " hostname = \"%s\";\n" |
c6c9e10f | 1868 | " domain = \"kernel\";\n" |
99dc9597 | 1869 | " sysname = \"%s\";\n" |
c6c9e10f MD |
1870 | " kernel_release = \"%s\";\n" |
1871 | " kernel_version = \"%s\";\n" | |
1872 | " tracer_name = \"lttng-modules\";\n" | |
1873 | " tracer_major = %d;\n" | |
1874 | " tracer_minor = %d;\n" | |
1875 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 1876 | "};\n\n", |
3d0d43db | 1877 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
1878 | utsname()->sysname, |
1879 | utsname()->release, | |
c6c9e10f MD |
1880 | utsname()->version, |
1881 | LTTNG_MODULES_MAJOR_VERSION, | |
1882 | LTTNG_MODULES_MINOR_VERSION, | |
1883 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
1884 | ); |
1885 | if (ret) | |
1886 | goto end; | |
1887 | ||
a3ccff4f MD |
1888 | ret = lttng_metadata_printf(session, |
1889 | "clock {\n" | |
a82c63f1 MD |
1890 | " name = %s;\n", |
1891 | "monotonic" | |
1892 | ); | |
1893 | if (ret) | |
1894 | goto end; | |
1895 | ||
1896 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1897 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1898 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1899 | clock_uuid_s |
1900 | ); | |
1901 | if (ret) | |
1902 | goto end; | |
1903 | } | |
1904 | ||
1905 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1906 | " description = \"Monotonic Clock\";\n" |
1907 | " freq = %llu; /* Frequency, in Hz */\n" | |
1908 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1909 | " offset = %llu;\n" | |
1910 | "};\n\n", | |
a3ccff4f MD |
1911 | (unsigned long long) trace_clock_freq(), |
1912 | (unsigned long long) measure_clock_offset() | |
1913 | ); | |
1914 | if (ret) | |
1915 | goto end; | |
1916 | ||
1917 | ret = lttng_metadata_printf(session, | |
1918 | "typealias integer {\n" | |
1919 | " size = 27; align = 1; signed = false;\n" | |
1920 | " map = clock.monotonic.value;\n" | |
1921 | "} := uint27_clock_monotonic_t;\n" | |
1922 | "\n" | |
1923 | "typealias integer {\n" | |
1924 | " size = 32; align = %u; signed = false;\n" | |
1925 | " map = clock.monotonic.value;\n" | |
1926 | "} := uint32_clock_monotonic_t;\n" | |
1927 | "\n" | |
1928 | "typealias integer {\n" | |
1929 | " size = 64; align = %u; signed = false;\n" | |
1930 | " map = clock.monotonic.value;\n" | |
1931 | "} := uint64_clock_monotonic_t;\n\n", | |
1932 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1933 | lttng_alignof(uint64_t) * CHAR_BIT | |
1934 | ); | |
1935 | if (ret) | |
1936 | goto end; | |
1937 | ||
a90917c3 | 1938 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1939 | if (ret) |
1940 | goto end; | |
1941 | ||
a90917c3 | 1942 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1943 | if (ret) |
1944 | goto end; | |
1945 | ||
c099397a MD |
1946 | skip_session: |
1947 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1948 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1949 | if (ret) |
1950 | goto end; | |
1951 | } | |
1952 | ||
1953 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1954 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1955 | if (ret) |
1956 | goto end; | |
1957 | } | |
1958 | session->metadata_dumped = 1; | |
1959 | end: | |
1960 | return ret; | |
1961 | } | |
1962 | ||
c0e31d2e | 1963 | /** |
a90917c3 | 1964 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1965 | * @transport: transport structure |
1966 | * | |
1967 | * Registers a transport which can be used as output to extract the data out of | |
1968 | * LTTng. The module calling this registration function must ensure that no | |
1969 | * trap-inducing code will be executed by the transport functions. E.g. | |
1970 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1971 | * is made visible to the transport function. This registration acts as a | |
1972 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1973 | * after its registration must it synchronize the TLBs. | |
1974 | */ | |
a90917c3 | 1975 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1976 | { |
1977 | /* | |
1978 | * Make sure no page fault can be triggered by the module about to be | |
1979 | * registered. We deal with this here so we don't have to call | |
1980 | * vmalloc_sync_all() in each module's init. | |
1981 | */ | |
6d2a620c | 1982 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1983 | |
1984 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1985 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1986 | mutex_unlock(&sessions_mutex); |
1987 | } | |
a90917c3 | 1988 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1989 | |
1990 | /** | |
a90917c3 | 1991 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1992 | * @transport: transport structure |
1993 | */ | |
a90917c3 | 1994 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1995 | { |
1996 | mutex_lock(&sessions_mutex); | |
1997 | list_del(&transport->node); | |
1998 | mutex_unlock(&sessions_mutex); | |
1999 | } | |
a90917c3 | 2000 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 2001 | |
a90917c3 | 2002 | static int __init lttng_events_init(void) |
4e3c1b9b | 2003 | { |
1c25284c MD |
2004 | int ret; |
2005 | ||
453b2495 JD |
2006 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
2007 | if (ret) | |
2008 | return ret; | |
2009 | ||
20591cf7 MD |
2010 | ret = lttng_tracepoint_init(); |
2011 | if (ret) | |
2012 | return ret; | |
a90917c3 | 2013 | event_cache = KMEM_CACHE(lttng_event, 0); |
20591cf7 MD |
2014 | if (!event_cache) { |
2015 | ret = -ENOMEM; | |
2016 | goto error_kmem; | |
2017 | } | |
80996790 | 2018 | ret = lttng_abi_init(); |
02119ee5 MD |
2019 | if (ret) |
2020 | goto error_abi; | |
0c956676 MD |
2021 | ret = lttng_logger_init(); |
2022 | if (ret) | |
2023 | goto error_logger; | |
4e3c1b9b | 2024 | return 0; |
0c956676 MD |
2025 | |
2026 | error_logger: | |
2027 | lttng_abi_exit(); | |
02119ee5 | 2028 | error_abi: |
1c25284c | 2029 | kmem_cache_destroy(event_cache); |
20591cf7 MD |
2030 | error_kmem: |
2031 | lttng_tracepoint_exit(); | |
1c25284c | 2032 | return ret; |
4e3c1b9b MD |
2033 | } |
2034 | ||
a90917c3 | 2035 | module_init(lttng_events_init); |
11b5a3c2 | 2036 | |
a90917c3 | 2037 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 2038 | { |
a90917c3 | 2039 | struct lttng_session *session, *tmpsession; |
92e94819 | 2040 | |
0c956676 | 2041 | lttng_logger_exit(); |
80996790 | 2042 | lttng_abi_exit(); |
92e94819 | 2043 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 2044 | lttng_session_destroy(session); |
11b5a3c2 | 2045 | kmem_cache_destroy(event_cache); |
20591cf7 | 2046 | lttng_tracepoint_exit(); |
4e3c1b9b | 2047 | } |
92e94819 | 2048 | |
a90917c3 | 2049 | module_exit(lttng_events_exit); |
11b5a3c2 | 2050 | |
92e94819 MD |
2051 | MODULE_LICENSE("GPL and additional rights"); |
2052 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
2053 | MODULE_DESCRIPTION("LTTng Events"); | |
9a9973ef MD |
2054 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
2055 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
309370e2 MD |
2056 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
2057 | LTTNG_MODULES_EXTRAVERSION); |