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/list.h> |
25 | #include <linux/mutex.h> | |
26 | #include <linux/sched.h> | |
11b5a3c2 | 27 | #include <linux/slab.h> |
c099397a | 28 | #include <linux/jiffies.h> |
99dc9597 | 29 | #include <linux/utsname.h> |
abc0446a | 30 | #include <linux/err.h> |
a864fb02 | 31 | #include "wrapper/uuid.h" |
b13f3ebe | 32 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
a82c63f1 | 33 | #include "wrapper/random.h" |
3a523f5b | 34 | #include "wrapper/tracepoint.h" |
b8590f40 | 35 | #include "lttng-kernel-version.h" |
a90917c3 MD |
36 | #include "lttng-events.h" |
37 | #include "lttng-tracer.h" | |
6dccd6c1 | 38 | #include "lttng-abi-old.h" |
4e3c1b9b | 39 | |
d83004aa JD |
40 | #define METADATA_CACHE_DEFAULT_SIZE 4096 |
41 | ||
4e3c1b9b | 42 | static LIST_HEAD(sessions); |
a90917c3 | 43 | static LIST_HEAD(lttng_transport_list); |
d83004aa JD |
44 | /* |
45 | * Protect the sessions and metadata caches. | |
46 | */ | |
4e3c1b9b MD |
47 | static DEFINE_MUTEX(sessions_mutex); |
48 | static struct kmem_cache *event_cache; | |
49 | ||
a90917c3 MD |
50 | static void _lttng_event_destroy(struct lttng_event *event); |
51 | static void _lttng_channel_destroy(struct lttng_channel *chan); | |
52 | static int _lttng_event_unregister(struct lttng_event *event); | |
c099397a | 53 | static |
a90917c3 MD |
54 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
55 | struct lttng_channel *chan, | |
56 | struct lttng_event *event); | |
c099397a | 57 | static |
a90917c3 | 58 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
d83004aa JD |
59 | static |
60 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream); | |
c099397a | 61 | |
c099397a | 62 | void synchronize_trace(void) |
abcca994 MD |
63 | { |
64 | synchronize_sched(); | |
b8590f40 MD |
65 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
66 | #ifdef CONFIG_PREEMPT_RT_FULL | |
67 | synchronize_rcu(); | |
68 | #endif | |
69 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ | |
abcca994 MD |
70 | #ifdef CONFIG_PREEMPT_RT |
71 | synchronize_rcu(); | |
72 | #endif | |
b8590f40 | 73 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
abcca994 MD |
74 | } |
75 | ||
a90917c3 | 76 | struct lttng_session *lttng_session_create(void) |
4e3c1b9b | 77 | { |
a90917c3 | 78 | struct lttng_session *session; |
d83004aa | 79 | struct lttng_metadata_cache *metadata_cache; |
4e3c1b9b MD |
80 | |
81 | mutex_lock(&sessions_mutex); | |
a90917c3 | 82 | session = kzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
4e3c1b9b | 83 | if (!session) |
d83004aa | 84 | goto err; |
4e3c1b9b | 85 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 86 | INIT_LIST_HEAD(&session->events); |
d793d5e1 | 87 | uuid_le_gen(&session->uuid); |
d83004aa JD |
88 | |
89 | metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache), | |
90 | GFP_KERNEL); | |
91 | if (!metadata_cache) | |
92 | goto err_free_session; | |
93 | metadata_cache->data = kzalloc(METADATA_CACHE_DEFAULT_SIZE, | |
94 | GFP_KERNEL); | |
95 | if (!metadata_cache->data) | |
96 | goto err_free_cache; | |
97 | metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE; | |
98 | kref_init(&metadata_cache->refcount); | |
99 | session->metadata_cache = metadata_cache; | |
100 | INIT_LIST_HEAD(&metadata_cache->metadata_stream); | |
a36580d5 MD |
101 | memcpy(&metadata_cache->uuid, &session->uuid, |
102 | sizeof(metadata_cache->uuid)); | |
4e3c1b9b MD |
103 | list_add(&session->list, &sessions); |
104 | mutex_unlock(&sessions_mutex); | |
105 | return session; | |
d83004aa JD |
106 | |
107 | err_free_cache: | |
108 | kfree(metadata_cache); | |
109 | err_free_session: | |
110 | kfree(session); | |
111 | err: | |
112 | mutex_unlock(&sessions_mutex); | |
113 | return NULL; | |
114 | } | |
115 | ||
116 | void metadata_cache_destroy(struct kref *kref) | |
117 | { | |
118 | struct lttng_metadata_cache *cache = | |
119 | container_of(kref, struct lttng_metadata_cache, refcount); | |
120 | kfree(cache->data); | |
121 | kfree(cache); | |
4e3c1b9b MD |
122 | } |
123 | ||
a90917c3 | 124 | void lttng_session_destroy(struct lttng_session *session) |
4e3c1b9b | 125 | { |
a90917c3 MD |
126 | struct lttng_channel *chan, *tmpchan; |
127 | struct lttng_event *event, *tmpevent; | |
d83004aa | 128 | struct lttng_metadata_stream *metadata_stream; |
dda6a249 | 129 | int ret; |
4e3c1b9b MD |
130 | |
131 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 132 | ACCESS_ONCE(session->active) = 0; |
1ec65de1 MD |
133 | list_for_each_entry(chan, &session->chan, list) { |
134 | ret = lttng_syscalls_unregister(chan); | |
135 | WARN_ON(ret); | |
136 | } | |
dda6a249 | 137 | list_for_each_entry(event, &session->events, list) { |
a90917c3 | 138 | ret = _lttng_event_unregister(event); |
dda6a249 MD |
139 | WARN_ON(ret); |
140 | } | |
abcca994 | 141 | synchronize_trace(); /* Wait for in-flight events to complete */ |
4e3c1b9b | 142 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
a90917c3 | 143 | _lttng_event_destroy(event); |
d83004aa JD |
144 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { |
145 | BUG_ON(chan->channel_type == METADATA_CHANNEL); | |
a90917c3 | 146 | _lttng_channel_destroy(chan); |
d83004aa JD |
147 | } |
148 | list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) | |
149 | _lttng_metadata_channel_hangup(metadata_stream); | |
150 | kref_put(&session->metadata_cache->refcount, metadata_cache_destroy); | |
4e3c1b9b MD |
151 | list_del(&session->list); |
152 | mutex_unlock(&sessions_mutex); | |
153 | kfree(session); | |
154 | } | |
155 | ||
a90917c3 | 156 | int lttng_session_enable(struct lttng_session *session) |
c0e31d2e MD |
157 | { |
158 | int ret = 0; | |
a90917c3 | 159 | struct lttng_channel *chan; |
c0e31d2e MD |
160 | |
161 | mutex_lock(&sessions_mutex); | |
162 | if (session->active) { | |
163 | ret = -EBUSY; | |
164 | goto end; | |
165 | } | |
c099397a MD |
166 | |
167 | /* | |
168 | * Snapshot the number of events per channel to know the type of header | |
169 | * we need to use. | |
170 | */ | |
171 | list_for_each_entry(chan, &session->chan, list) { | |
172 | if (chan->header_type) | |
173 | continue; /* don't change it if session stop/restart */ | |
174 | if (chan->free_event_id < 31) | |
175 | chan->header_type = 1; /* compact */ | |
176 | else | |
177 | chan->header_type = 2; /* large */ | |
178 | } | |
179 | ||
52fc2e1f | 180 | ACCESS_ONCE(session->active) = 1; |
8070f5c0 | 181 | ACCESS_ONCE(session->been_active) = 1; |
a90917c3 | 182 | ret = _lttng_session_metadata_statedump(session); |
c337ddc2 MD |
183 | if (ret) { |
184 | ACCESS_ONCE(session->active) = 0; | |
185 | goto end; | |
186 | } | |
187 | ret = lttng_statedump_start(session); | |
360f38ea | 188 | if (ret) |
c099397a | 189 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
190 | end: |
191 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 192 | return ret; |
c0e31d2e MD |
193 | } |
194 | ||
a90917c3 | 195 | int lttng_session_disable(struct lttng_session *session) |
c0e31d2e MD |
196 | { |
197 | int ret = 0; | |
198 | ||
199 | mutex_lock(&sessions_mutex); | |
200 | if (!session->active) { | |
201 | ret = -EBUSY; | |
202 | goto end; | |
203 | } | |
52fc2e1f | 204 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
205 | end: |
206 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 207 | return ret; |
c0e31d2e MD |
208 | } |
209 | ||
a90917c3 | 210 | int lttng_channel_enable(struct lttng_channel *channel) |
e64957da MD |
211 | { |
212 | int old; | |
213 | ||
d83004aa | 214 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 215 | return -EPERM; |
e64957da MD |
216 | old = xchg(&channel->enabled, 1); |
217 | if (old) | |
218 | return -EEXIST; | |
219 | return 0; | |
220 | } | |
221 | ||
a90917c3 | 222 | int lttng_channel_disable(struct lttng_channel *channel) |
e64957da MD |
223 | { |
224 | int old; | |
225 | ||
d83004aa | 226 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 227 | return -EPERM; |
e64957da MD |
228 | old = xchg(&channel->enabled, 0); |
229 | if (!old) | |
230 | return -EEXIST; | |
231 | return 0; | |
232 | } | |
233 | ||
a90917c3 | 234 | int lttng_event_enable(struct lttng_event *event) |
e64957da MD |
235 | { |
236 | int old; | |
237 | ||
d83004aa | 238 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 239 | return -EPERM; |
e64957da MD |
240 | old = xchg(&event->enabled, 1); |
241 | if (old) | |
242 | return -EEXIST; | |
243 | return 0; | |
244 | } | |
245 | ||
a90917c3 | 246 | int lttng_event_disable(struct lttng_event *event) |
e64957da MD |
247 | { |
248 | int old; | |
249 | ||
d83004aa | 250 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 251 | return -EPERM; |
e64957da MD |
252 | old = xchg(&event->enabled, 0); |
253 | if (!old) | |
254 | return -EEXIST; | |
255 | return 0; | |
256 | } | |
257 | ||
a90917c3 | 258 | static struct lttng_transport *lttng_transport_find(const char *name) |
f3d01b96 | 259 | { |
a90917c3 | 260 | struct lttng_transport *transport; |
f3d01b96 | 261 | |
a90917c3 | 262 | list_for_each_entry(transport, <tng_transport_list, node) { |
f3d01b96 MD |
263 | if (!strcmp(transport->name, name)) |
264 | return transport; | |
265 | } | |
266 | return NULL; | |
267 | } | |
268 | ||
a90917c3 | 269 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
5dbbdb43 MD |
270 | const char *transport_name, |
271 | void *buf_addr, | |
4e3c1b9b MD |
272 | size_t subbuf_size, size_t num_subbuf, |
273 | unsigned int switch_timer_interval, | |
d83004aa JD |
274 | unsigned int read_timer_interval, |
275 | enum channel_type channel_type) | |
4e3c1b9b | 276 | { |
a90917c3 MD |
277 | struct lttng_channel *chan; |
278 | struct lttng_transport *transport = NULL; | |
4e3c1b9b MD |
279 | |
280 | mutex_lock(&sessions_mutex); | |
d83004aa | 281 | if (session->been_active && channel_type != METADATA_CHANNEL) |
e5382b6d | 282 | goto active; /* Refuse to add channel to active session */ |
a90917c3 | 283 | transport = lttng_transport_find(transport_name); |
f3d01b96 MD |
284 | if (!transport) { |
285 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
286 | transport_name); | |
c0e31d2e | 287 | goto notransport; |
f3d01b96 | 288 | } |
a33c9927 MD |
289 | if (!try_module_get(transport->owner)) { |
290 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
291 | goto notransport; | |
292 | } | |
a90917c3 | 293 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
4e3c1b9b | 294 | if (!chan) |
c0e31d2e | 295 | goto nomem; |
4e3c1b9b | 296 | chan->session = session; |
05d32c64 | 297 | chan->id = session->free_chan_id++; |
3b731ab1 | 298 | chan->ops = &transport->ops; |
125b4df4 MD |
299 | /* |
300 | * Note: the channel creation op already writes into the packet | |
301 | * headers. Therefore the "chan" information used as input | |
302 | * should be already accessible. | |
303 | */ | |
5f5ddf01 MD |
304 | chan->chan = transport->ops.channel_create(transport_name, |
305 | chan, buf_addr, subbuf_size, num_subbuf, | |
306 | switch_timer_interval, read_timer_interval); | |
f3d01b96 MD |
307 | if (!chan->chan) |
308 | goto create_error; | |
e64957da | 309 | chan->enabled = 1; |
a33c9927 | 310 | chan->transport = transport; |
d83004aa | 311 | chan->channel_type = channel_type; |
4e3c1b9b MD |
312 | list_add(&chan->list, &session->chan); |
313 | mutex_unlock(&sessions_mutex); | |
314 | return chan; | |
315 | ||
f3d01b96 MD |
316 | create_error: |
317 | kfree(chan); | |
c0e31d2e | 318 | nomem: |
a33c9927 MD |
319 | if (transport) |
320 | module_put(transport->owner); | |
c0e31d2e | 321 | notransport: |
e5382b6d | 322 | active: |
4e3c1b9b MD |
323 | mutex_unlock(&sessions_mutex); |
324 | return NULL; | |
325 | } | |
326 | ||
327 | /* | |
d83004aa JD |
328 | * Only used internally at session destruction for per-cpu channels, and |
329 | * when metadata channel is released. | |
330 | * Needs to be called with sessions mutex held. | |
4e3c1b9b | 331 | */ |
aa7c23a9 | 332 | static |
a90917c3 | 333 | void _lttng_channel_destroy(struct lttng_channel *chan) |
4e3c1b9b | 334 | { |
11b5a3c2 | 335 | chan->ops->channel_destroy(chan->chan); |
a33c9927 | 336 | module_put(chan->transport->owner); |
4e3c1b9b | 337 | list_del(&chan->list); |
8070f5c0 | 338 | lttng_destroy_context(chan->ctx); |
4e3c1b9b MD |
339 | kfree(chan); |
340 | } | |
341 | ||
d83004aa JD |
342 | void lttng_metadata_channel_destroy(struct lttng_channel *chan) |
343 | { | |
344 | BUG_ON(chan->channel_type != METADATA_CHANNEL); | |
345 | ||
346 | /* Protect the metadata cache with the sessions_mutex. */ | |
347 | mutex_lock(&sessions_mutex); | |
348 | _lttng_channel_destroy(chan); | |
349 | mutex_unlock(&sessions_mutex); | |
350 | } | |
351 | EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy); | |
352 | ||
353 | static | |
354 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream) | |
355 | { | |
356 | stream->finalized = 1; | |
357 | wake_up_interruptible(&stream->read_wait); | |
358 | } | |
359 | ||
e5382b6d MD |
360 | /* |
361 | * Supports event creation while tracing session is active. | |
362 | */ | |
a90917c3 | 363 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
d6d808f3 | 364 | struct lttng_kernel_event *event_param, |
259b6cb3 MD |
365 | void *filter, |
366 | const struct lttng_event_desc *internal_desc) | |
4e3c1b9b | 367 | { |
a90917c3 | 368 | struct lttng_event *event; |
3d084699 | 369 | int ret; |
4e3c1b9b MD |
370 | |
371 | mutex_lock(&sessions_mutex); | |
abc0446a | 372 | if (chan->free_event_id == -1U) { |
4cf0bf51 | 373 | ret = -EMFILE; |
e5382b6d | 374 | goto full; |
abc0446a | 375 | } |
4e3c1b9b | 376 | /* |
dda6a249 MD |
377 | * This is O(n^2) (for each event, the loop is called at event |
378 | * creation). Might require a hash if we have lots of events. | |
4e3c1b9b | 379 | */ |
abc0446a MD |
380 | list_for_each_entry(event, &chan->session->events, list) { |
381 | if (!strcmp(event->desc->name, event_param->name)) { | |
f046a95d MD |
382 | /* |
383 | * Allow events with the same name to appear in | |
384 | * different channels. | |
385 | */ | |
386 | if (event->chan == chan) { | |
387 | ret = -EEXIST; | |
388 | goto exist; | |
389 | } | |
abc0446a MD |
390 | } |
391 | } | |
11b5a3c2 | 392 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
abc0446a | 393 | if (!event) { |
4cf0bf51 | 394 | ret = -ENOMEM; |
4e3c1b9b | 395 | goto cache_error; |
abc0446a | 396 | } |
4e3c1b9b MD |
397 | event->chan = chan; |
398 | event->filter = filter; | |
e5382b6d | 399 | event->id = chan->free_event_id++; |
e64957da | 400 | event->enabled = 1; |
d6d808f3 | 401 | event->instrumentation = event_param->instrumentation; |
a90917c3 | 402 | /* Populate lttng_event structure before tracepoint registration. */ |
e5382b6d | 403 | smp_wmb(); |
d6d808f3 | 404 | switch (event_param->instrumentation) { |
ab2277d6 | 405 | case LTTNG_KERNEL_TRACEPOINT: |
a90917c3 | 406 | event->desc = lttng_event_get(event_param->name); |
abc0446a | 407 | if (!event->desc) { |
4cf0bf51 | 408 | ret = -ENOENT; |
d3dbe23c | 409 | goto register_error; |
abc0446a | 410 | } |
20591cf7 | 411 | ret = lttng_wrapper_tracepoint_probe_register(event->desc->kname, |
d3dbe23c MD |
412 | event->desc->probe_callback, |
413 | event); | |
abc0446a | 414 | if (ret) { |
4cf0bf51 | 415 | ret = -EINVAL; |
11b5a3c2 | 416 | goto register_error; |
abc0446a | 417 | } |
baf20995 | 418 | break; |
ab2277d6 | 419 | case LTTNG_KERNEL_KPROBE: |
30bdb6e4 | 420 | ret = lttng_kprobes_register(event_param->name, |
f17701fb MD |
421 | event_param->u.kprobe.symbol_name, |
422 | event_param->u.kprobe.offset, | |
423 | event_param->u.kprobe.addr, | |
424 | event); | |
abc0446a | 425 | if (ret) { |
4cf0bf51 | 426 | ret = -EINVAL; |
d6d808f3 | 427 | goto register_error; |
abc0446a | 428 | } |
edeb3137 MD |
429 | ret = try_module_get(event->desc->owner); |
430 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 431 | break; |
7371f44c MD |
432 | case LTTNG_KERNEL_KRETPROBE: |
433 | { | |
a90917c3 | 434 | struct lttng_event *event_return; |
7371f44c MD |
435 | |
436 | /* kretprobe defines 2 events */ | |
437 | event_return = | |
438 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
abc0446a | 439 | if (!event_return) { |
4cf0bf51 | 440 | ret = -ENOMEM; |
7371f44c | 441 | goto register_error; |
abc0446a | 442 | } |
7371f44c MD |
443 | event_return->chan = chan; |
444 | event_return->filter = filter; | |
445 | event_return->id = chan->free_event_id++; | |
446 | event_return->enabled = 1; | |
447 | event_return->instrumentation = event_param->instrumentation; | |
448 | /* | |
a90917c3 | 449 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
450 | */ |
451 | smp_wmb(); | |
452 | ret = lttng_kretprobes_register(event_param->name, | |
453 | event_param->u.kretprobe.symbol_name, | |
454 | event_param->u.kretprobe.offset, | |
455 | event_param->u.kretprobe.addr, | |
456 | event, event_return); | |
457 | if (ret) { | |
458 | kmem_cache_free(event_cache, event_return); | |
4cf0bf51 | 459 | ret = -EINVAL; |
7371f44c MD |
460 | goto register_error; |
461 | } | |
462 | /* Take 2 refs on the module: one per event. */ | |
463 | ret = try_module_get(event->desc->owner); | |
464 | WARN_ON_ONCE(!ret); | |
465 | ret = try_module_get(event->desc->owner); | |
466 | WARN_ON_ONCE(!ret); | |
a90917c3 | 467 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c | 468 | event_return); |
abc0446a | 469 | WARN_ON_ONCE(ret > 0); |
7371f44c MD |
470 | if (ret) { |
471 | kmem_cache_free(event_cache, event_return); | |
472 | module_put(event->desc->owner); | |
473 | module_put(event->desc->owner); | |
474 | goto statedump_error; | |
475 | } | |
476 | list_add(&event_return->list, &chan->session->events); | |
477 | break; | |
478 | } | |
ab2277d6 | 479 | case LTTNG_KERNEL_FUNCTION: |
30bdb6e4 | 480 | ret = lttng_ftrace_register(event_param->name, |
e0a7a7c4 MD |
481 | event_param->u.ftrace.symbol_name, |
482 | event); | |
abc0446a | 483 | if (ret) { |
e0a7a7c4 | 484 | goto register_error; |
abc0446a | 485 | } |
edeb3137 MD |
486 | ret = try_module_get(event->desc->owner); |
487 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 488 | break; |
1ec65de1 | 489 | case LTTNG_KERNEL_NOOP: |
259b6cb3 | 490 | event->desc = internal_desc; |
abc0446a | 491 | if (!event->desc) { |
4cf0bf51 | 492 | ret = -EINVAL; |
259b6cb3 | 493 | goto register_error; |
abc0446a | 494 | } |
1ec65de1 | 495 | break; |
baf20995 MD |
496 | default: |
497 | WARN_ON_ONCE(1); | |
4cf0bf51 | 498 | ret = -EINVAL; |
df07930b | 499 | goto register_error; |
baf20995 | 500 | } |
a90917c3 | 501 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
abc0446a MD |
502 | WARN_ON_ONCE(ret > 0); |
503 | if (ret) { | |
c099397a | 504 | goto statedump_error; |
abc0446a | 505 | } |
dda6a249 | 506 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 507 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
508 | return event; |
509 | ||
c099397a | 510 | statedump_error: |
259b6cb3 | 511 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 512 | register_error: |
11b5a3c2 | 513 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
514 | cache_error: |
515 | exist: | |
e5382b6d | 516 | full: |
4e3c1b9b | 517 | mutex_unlock(&sessions_mutex); |
4cf0bf51 | 518 | return ERR_PTR(ret); |
4e3c1b9b MD |
519 | } |
520 | ||
521 | /* | |
522 | * Only used internally at session destruction. | |
523 | */ | |
a90917c3 | 524 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 525 | { |
11b5a3c2 MD |
526 | int ret = -EINVAL; |
527 | ||
38d024ae | 528 | switch (event->instrumentation) { |
ab2277d6 | 529 | case LTTNG_KERNEL_TRACEPOINT: |
20591cf7 | 530 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
85a9ca7f | 531 | event->desc->probe_callback, |
11b5a3c2 MD |
532 | event); |
533 | if (ret) | |
534 | return ret; | |
baf20995 | 535 | break; |
ab2277d6 | 536 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 537 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
538 | ret = 0; |
539 | break; | |
7371f44c MD |
540 | case LTTNG_KERNEL_KRETPROBE: |
541 | lttng_kretprobes_unregister(event); | |
542 | ret = 0; | |
543 | break; | |
ab2277d6 | 544 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
545 | lttng_ftrace_unregister(event); |
546 | ret = 0; | |
547 | break; | |
259b6cb3 MD |
548 | case LTTNG_KERNEL_NOOP: |
549 | ret = 0; | |
550 | break; | |
baf20995 MD |
551 | default: |
552 | WARN_ON_ONCE(1); | |
553 | } | |
dda6a249 MD |
554 | return ret; |
555 | } | |
556 | ||
557 | /* | |
558 | * Only used internally at session destruction. | |
559 | */ | |
be066e6c | 560 | static |
a90917c3 | 561 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 562 | { |
edeb3137 MD |
563 | switch (event->instrumentation) { |
564 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 565 | lttng_event_put(event->desc); |
edeb3137 MD |
566 | break; |
567 | case LTTNG_KERNEL_KPROBE: | |
568 | module_put(event->desc->owner); | |
569 | lttng_kprobes_destroy_private(event); | |
570 | break; | |
7371f44c MD |
571 | case LTTNG_KERNEL_KRETPROBE: |
572 | module_put(event->desc->owner); | |
573 | lttng_kretprobes_destroy_private(event); | |
574 | break; | |
edeb3137 MD |
575 | case LTTNG_KERNEL_FUNCTION: |
576 | module_put(event->desc->owner); | |
577 | lttng_ftrace_destroy_private(event); | |
578 | break; | |
259b6cb3 MD |
579 | case LTTNG_KERNEL_NOOP: |
580 | break; | |
edeb3137 MD |
581 | default: |
582 | WARN_ON_ONCE(1); | |
583 | } | |
dda6a249 | 584 | list_del(&event->list); |
8070f5c0 | 585 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 586 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
587 | } |
588 | ||
1ec3f75a | 589 | /* |
d83004aa JD |
590 | * Serialize at most one packet worth of metadata into a metadata |
591 | * channel. | |
1ec3f75a MD |
592 | * We have exclusive access to our metadata buffer (protected by the |
593 | * sessions_mutex), so we can do racy operations such as looking for | |
594 | * remaining space left in packet and write, since mutual exclusion | |
595 | * protects us from concurrent writes. | |
35097f36 JD |
596 | * Returns the number of bytes written in the channel, 0 if no data |
597 | * was written and a negative value on error. | |
1ec3f75a | 598 | */ |
b3b8072b MD |
599 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
600 | struct channel *chan) | |
d83004aa JD |
601 | { |
602 | struct lib_ring_buffer_ctx ctx; | |
603 | int ret = 0; | |
604 | size_t len, reserve_len; | |
605 | ||
f613e3e6 MD |
606 | /* |
607 | * Ensure we support mutiple get_next / put sequences followed | |
de23d59d MD |
608 | * by put_next. The metadata stream lock internally protects |
609 | * reading the metadata cache. It can indeed be read | |
610 | * concurrently by "get_next_subbuf" and "flush" operations on | |
611 | * the buffer invoked by different processes. | |
f613e3e6 | 612 | */ |
de23d59d | 613 | mutex_lock(&stream->lock); |
f613e3e6 MD |
614 | WARN_ON(stream->metadata_in < stream->metadata_out); |
615 | if (stream->metadata_in != stream->metadata_out) | |
de23d59d | 616 | goto end; |
f613e3e6 | 617 | |
d83004aa | 618 | len = stream->metadata_cache->metadata_written - |
f613e3e6 | 619 | stream->metadata_in; |
9de2c215 | 620 | if (!len) |
de23d59d | 621 | goto end; |
d83004aa | 622 | reserve_len = min_t(size_t, |
b3b8072b | 623 | stream->transport->ops.packet_avail_size(chan), |
d83004aa | 624 | len); |
b3b8072b | 625 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
d83004aa JD |
626 | sizeof(char), -1); |
627 | /* | |
628 | * If reservation failed, return an error to the caller. | |
629 | */ | |
b3b8072b | 630 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
d83004aa JD |
631 | if (ret != 0) { |
632 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); | |
633 | goto end; | |
634 | } | |
b3b8072b | 635 | stream->transport->ops.event_write(&ctx, |
f613e3e6 | 636 | stream->metadata_cache->data + stream->metadata_in, |
d83004aa | 637 | reserve_len); |
b3b8072b | 638 | stream->transport->ops.event_commit(&ctx); |
f613e3e6 | 639 | stream->metadata_in += reserve_len; |
d83004aa JD |
640 | ret = reserve_len; |
641 | ||
642 | end: | |
de23d59d | 643 | mutex_unlock(&stream->lock); |
d83004aa JD |
644 | return ret; |
645 | } | |
646 | ||
647 | /* | |
648 | * Write the metadata to the metadata cache. | |
649 | * Must be called with sessions_mutex held. | |
650 | */ | |
a90917c3 | 651 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
652 | const char *fmt, ...) |
653 | { | |
c099397a | 654 | char *str; |
d83004aa | 655 | size_t len; |
c099397a | 656 | va_list ap; |
d83004aa | 657 | struct lttng_metadata_stream *stream; |
c099397a MD |
658 | |
659 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
660 | ||
661 | va_start(ap, fmt); | |
662 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
663 | va_end(ap); | |
664 | if (!str) | |
665 | return -ENOMEM; | |
666 | ||
1ec3f75a | 667 | len = strlen(str); |
d83004aa JD |
668 | if (session->metadata_cache->metadata_written + len > |
669 | session->metadata_cache->cache_alloc) { | |
670 | char *tmp_cache_realloc; | |
671 | unsigned int tmp_cache_alloc_size; | |
672 | ||
673 | tmp_cache_alloc_size = max_t(unsigned int, | |
674 | session->metadata_cache->cache_alloc + len, | |
675 | session->metadata_cache->cache_alloc << 1); | |
676 | tmp_cache_realloc = krealloc(session->metadata_cache->data, | |
677 | tmp_cache_alloc_size, GFP_KERNEL); | |
678 | if (!tmp_cache_realloc) | |
679 | goto err; | |
680 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; | |
681 | session->metadata_cache->data = tmp_cache_realloc; | |
c099397a | 682 | } |
d83004aa JD |
683 | memcpy(session->metadata_cache->data + |
684 | session->metadata_cache->metadata_written, | |
685 | str, len); | |
686 | session->metadata_cache->metadata_written += len; | |
c099397a | 687 | kfree(str); |
d83004aa JD |
688 | |
689 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) | |
690 | wake_up_interruptible(&stream->read_wait); | |
691 | ||
692 | return 0; | |
693 | ||
694 | err: | |
695 | kfree(str); | |
696 | return -ENOMEM; | |
c099397a MD |
697 | } |
698 | ||
d83004aa JD |
699 | /* |
700 | * Must be called with sessions_mutex held. | |
701 | */ | |
c099397a | 702 | static |
a90917c3 | 703 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 704 | const struct lttng_event_field *field) |
c099397a | 705 | { |
c099397a | 706 | int ret = 0; |
c099397a | 707 | |
8070f5c0 MD |
708 | switch (field->type.atype) { |
709 | case atype_integer: | |
710 | ret = lttng_metadata_printf(session, | |
244465ab | 711 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
712 | field->type.u.basic.integer.size, |
713 | field->type.u.basic.integer.alignment, | |
714 | field->type.u.basic.integer.signedness, | |
715 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
716 | ? "none" | |
717 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
718 | ? "UTF8" | |
719 | : "ASCII", | |
720 | field->type.u.basic.integer.base, | |
c099397a | 721 | #ifdef __BIG_ENDIAN |
8070f5c0 | 722 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 723 | #else |
8070f5c0 | 724 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 725 | #endif |
8070f5c0 MD |
726 | field->name); |
727 | break; | |
728 | case atype_enum: | |
729 | ret = lttng_metadata_printf(session, | |
244465ab | 730 | " %s _%s;\n", |
8070f5c0 MD |
731 | field->type.u.basic.enumeration.name, |
732 | field->name); | |
733 | break; | |
734 | case atype_array: | |
735 | { | |
736 | const struct lttng_basic_type *elem_type; | |
737 | ||
738 | elem_type = &field->type.u.array.elem_type; | |
739 | ret = lttng_metadata_printf(session, | |
244465ab | 740 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
741 | elem_type->u.basic.integer.size, |
742 | elem_type->u.basic.integer.alignment, | |
743 | elem_type->u.basic.integer.signedness, | |
744 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
745 | ? "none" | |
746 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
747 | ? "UTF8" | |
748 | : "ASCII", | |
749 | elem_type->u.basic.integer.base, | |
8fa75f34 | 750 | #ifdef __BIG_ENDIAN |
8070f5c0 | 751 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 752 | #else |
8070f5c0 | 753 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 754 | #endif |
8070f5c0 MD |
755 | field->name, field->type.u.array.length); |
756 | break; | |
757 | } | |
758 | case atype_sequence: | |
759 | { | |
760 | const struct lttng_basic_type *elem_type; | |
761 | const struct lttng_basic_type *length_type; | |
762 | ||
763 | elem_type = &field->type.u.sequence.elem_type; | |
764 | length_type = &field->type.u.sequence.length_type; | |
765 | ret = lttng_metadata_printf(session, | |
766 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 767 | length_type->u.basic.integer.size, |
32257272 | 768 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
769 | length_type->u.basic.integer.signedness, |
770 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
771 | ? "none" | |
0635cdd4 | 772 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 773 | ? "UTF8" |
0635cdd4 | 774 | : "ASCII"), |
8070f5c0 | 775 | length_type->u.basic.integer.base, |
e0a7a7c4 | 776 | #ifdef __BIG_ENDIAN |
8070f5c0 | 777 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 778 | #else |
0635cdd4 | 779 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 780 | #endif |
27d2368e MD |
781 | field->name); |
782 | if (ret) | |
783 | return ret; | |
784 | ||
785 | ret = lttng_metadata_printf(session, | |
244465ab | 786 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 787 | elem_type->u.basic.integer.size, |
32257272 | 788 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
789 | elem_type->u.basic.integer.signedness, |
790 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
791 | ? "none" | |
0635cdd4 | 792 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 793 | ? "UTF8" |
0635cdd4 | 794 | : "ASCII"), |
8070f5c0 | 795 | elem_type->u.basic.integer.base, |
8fa75f34 | 796 | #ifdef __BIG_ENDIAN |
8070f5c0 | 797 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 798 | #else |
8070f5c0 | 799 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 800 | #endif |
8070f5c0 | 801 | field->name, |
27d2368e | 802 | field->name); |
8070f5c0 MD |
803 | break; |
804 | } | |
c099397a | 805 | |
8070f5c0 MD |
806 | case atype_string: |
807 | /* Default encoding is UTF8 */ | |
808 | ret = lttng_metadata_printf(session, | |
244465ab | 809 | " string%s _%s;\n", |
8070f5c0 MD |
810 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
811 | " { encoding = ASCII; }" : "", | |
812 | field->name); | |
813 | break; | |
814 | default: | |
815 | WARN_ON_ONCE(1); | |
816 | return -EINVAL; | |
817 | } | |
818 | return ret; | |
819 | } | |
820 | ||
821 | static | |
a90917c3 | 822 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
823 | struct lttng_ctx *ctx) |
824 | { | |
825 | int ret = 0; | |
826 | int i; | |
827 | ||
828 | if (!ctx) | |
829 | return 0; | |
830 | for (i = 0; i < ctx->nr_fields; i++) { | |
831 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
832 | ||
a90917c3 | 833 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
834 | if (ret) |
835 | return ret; | |
836 | } | |
837 | return ret; | |
838 | } | |
839 | ||
840 | static | |
a90917c3 MD |
841 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
842 | struct lttng_event *event) | |
8070f5c0 MD |
843 | { |
844 | const struct lttng_event_desc *desc = event->desc; | |
845 | int ret = 0; | |
846 | int i; | |
847 | ||
848 | for (i = 0; i < desc->nr_fields; i++) { | |
849 | const struct lttng_event_field *field = &desc->fields[i]; | |
850 | ||
a90917c3 | 851 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
852 | if (ret) |
853 | return ret; | |
c099397a MD |
854 | } |
855 | return ret; | |
856 | } | |
857 | ||
d83004aa JD |
858 | /* |
859 | * Must be called with sessions_mutex held. | |
860 | */ | |
c099397a | 861 | static |
a90917c3 MD |
862 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
863 | struct lttng_channel *chan, | |
864 | struct lttng_event *event) | |
c099397a MD |
865 | { |
866 | int ret = 0; | |
867 | ||
868 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
869 | return 0; | |
d83004aa | 870 | if (chan->channel_type == METADATA_CHANNEL) |
c099397a MD |
871 | return 0; |
872 | ||
873 | ret = lttng_metadata_printf(session, | |
874 | "event {\n" | |
ae734547 | 875 | " name = \"%s\";\n" |
c099397a | 876 | " id = %u;\n" |
b9074a1b | 877 | " stream_id = %u;\n", |
c099397a MD |
878 | event->desc->name, |
879 | event->id, | |
880 | event->chan->id); | |
881 | if (ret) | |
882 | goto end; | |
883 | ||
b9074a1b MD |
884 | if (event->ctx) { |
885 | ret = lttng_metadata_printf(session, | |
886 | " context := struct {\n"); | |
887 | if (ret) | |
888 | goto end; | |
889 | } | |
a90917c3 | 890 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
891 | if (ret) |
892 | goto end; | |
b9074a1b MD |
893 | if (event->ctx) { |
894 | ret = lttng_metadata_printf(session, | |
895 | " };\n"); | |
896 | if (ret) | |
897 | goto end; | |
898 | } | |
8070f5c0 MD |
899 | |
900 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
901 | " fields := struct {\n" |
902 | ); | |
903 | if (ret) | |
904 | goto end; | |
905 | ||
a90917c3 | 906 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
907 | if (ret) |
908 | goto end; | |
909 | ||
910 | /* | |
911 | * LTTng space reservation can only reserve multiples of the | |
912 | * byte size. | |
913 | */ | |
914 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
915 | " };\n" |
916 | "};\n\n"); | |
c099397a MD |
917 | if (ret) |
918 | goto end; | |
919 | ||
c099397a MD |
920 | event->metadata_dumped = 1; |
921 | end: | |
922 | return ret; | |
923 | ||
924 | } | |
925 | ||
d83004aa JD |
926 | /* |
927 | * Must be called with sessions_mutex held. | |
928 | */ | |
c099397a | 929 | static |
a90917c3 MD |
930 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
931 | struct lttng_channel *chan) | |
c099397a MD |
932 | { |
933 | int ret = 0; | |
934 | ||
935 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
936 | return 0; | |
d83004aa JD |
937 | |
938 | if (chan->channel_type == METADATA_CHANNEL) | |
c099397a MD |
939 | return 0; |
940 | ||
941 | WARN_ON_ONCE(!chan->header_type); | |
942 | ret = lttng_metadata_printf(session, | |
943 | "stream {\n" | |
944 | " id = %u;\n" | |
9115fbdc | 945 | " event.header := %s;\n" |
b9074a1b | 946 | " packet.context := struct packet_context;\n", |
c099397a MD |
947 | chan->id, |
948 | chan->header_type == 1 ? "struct event_header_compact" : | |
949 | "struct event_header_large"); | |
950 | if (ret) | |
951 | goto end; | |
952 | ||
b9074a1b MD |
953 | if (chan->ctx) { |
954 | ret = lttng_metadata_printf(session, | |
955 | " event.context := struct {\n"); | |
956 | if (ret) | |
957 | goto end; | |
958 | } | |
a90917c3 | 959 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
960 | if (ret) |
961 | goto end; | |
b9074a1b MD |
962 | if (chan->ctx) { |
963 | ret = lttng_metadata_printf(session, | |
964 | " };\n"); | |
965 | if (ret) | |
966 | goto end; | |
967 | } | |
8070f5c0 MD |
968 | |
969 | ret = lttng_metadata_printf(session, | |
b9074a1b | 970 | "};\n\n"); |
8070f5c0 | 971 | |
c099397a MD |
972 | chan->metadata_dumped = 1; |
973 | end: | |
974 | return ret; | |
975 | } | |
976 | ||
d83004aa JD |
977 | /* |
978 | * Must be called with sessions_mutex held. | |
979 | */ | |
9115fbdc | 980 | static |
a90917c3 | 981 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
982 | { |
983 | return lttng_metadata_printf(session, | |
984 | "struct packet_context {\n" | |
a3ccff4f MD |
985 | " uint64_clock_monotonic_t timestamp_begin;\n" |
986 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
987 | " uint64_t content_size;\n" |
988 | " uint64_t packet_size;\n" | |
a9afe705 | 989 | " unsigned long events_discarded;\n" |
9115fbdc | 990 | " uint32_t cpu_id;\n" |
c6dfdf6f | 991 | "};\n\n" |
9115fbdc MD |
992 | ); |
993 | } | |
994 | ||
995 | /* | |
996 | * Compact header: | |
997 | * id: range: 0 - 30. | |
998 | * id 31 is reserved to indicate an extended header. | |
999 | * | |
1000 | * Large header: | |
1001 | * id: range: 0 - 65534. | |
1002 | * id 65535 is reserved to indicate an extended header. | |
d83004aa JD |
1003 | * |
1004 | * Must be called with sessions_mutex held. | |
9115fbdc MD |
1005 | */ |
1006 | static | |
a90917c3 | 1007 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
1008 | { |
1009 | return lttng_metadata_printf(session, | |
1010 | "struct event_header_compact {\n" | |
1011 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
1012 | " variant <id> {\n" | |
1013 | " struct {\n" | |
a3ccff4f | 1014 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1015 | " } compact;\n" |
1016 | " struct {\n" | |
1017 | " uint32_t id;\n" | |
a3ccff4f | 1018 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1019 | " } extended;\n" |
1020 | " } v;\n" | |
1021 | "} align(%u);\n" | |
1022 | "\n" | |
1023 | "struct event_header_large {\n" | |
1024 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
1025 | " variant <id> {\n" | |
1026 | " struct {\n" | |
a3ccff4f | 1027 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1028 | " } compact;\n" |
1029 | " struct {\n" | |
1030 | " uint32_t id;\n" | |
a3ccff4f | 1031 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1032 | " } extended;\n" |
1033 | " } v;\n" | |
1034 | "} align(%u);\n\n", | |
a90917c3 MD |
1035 | lttng_alignof(uint32_t) * CHAR_BIT, |
1036 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
1037 | ); |
1038 | } | |
1039 | ||
a3ccff4f MD |
1040 | /* |
1041 | * Approximation of NTP time of day to clock monotonic correlation, | |
1042 | * taken at start of trace. | |
1043 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
1044 | * in future versions. | |
1045 | */ | |
1046 | static | |
1047 | uint64_t measure_clock_offset(void) | |
1048 | { | |
1049 | uint64_t offset, monotonic[2], realtime; | |
1050 | struct timespec rts = { 0, 0 }; | |
1051 | unsigned long flags; | |
1052 | ||
1053 | /* Disable interrupts to increase correlation precision. */ | |
1054 | local_irq_save(flags); | |
1055 | monotonic[0] = trace_clock_read64(); | |
1056 | getnstimeofday(&rts); | |
1057 | monotonic[1] = trace_clock_read64(); | |
1058 | local_irq_restore(flags); | |
1059 | ||
1060 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 1061 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
1062 | realtime += rts.tv_nsec; |
1063 | offset = realtime - offset; | |
1064 | return offset; | |
1065 | } | |
1066 | ||
c099397a MD |
1067 | /* |
1068 | * Output metadata into this session's metadata buffers. | |
d83004aa | 1069 | * Must be called with sessions_mutex held. |
c099397a MD |
1070 | */ |
1071 | static | |
a90917c3 | 1072 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 1073 | { |
30bdb6e4 | 1074 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 1075 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
1076 | struct lttng_channel *chan; |
1077 | struct lttng_event *event; | |
c099397a MD |
1078 | int ret = 0; |
1079 | ||
1080 | if (!ACCESS_ONCE(session->active)) | |
1081 | return 0; | |
1082 | if (session->metadata_dumped) | |
1083 | goto skip_session; | |
c099397a | 1084 | |
d793d5e1 | 1085 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
1086 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
1087 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
1088 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
1089 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
1090 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
1091 | |
1092 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1093 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
1094 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
1095 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
1096 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 1097 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
1098 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
1099 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
1100 | "\n" |
1101 | "trace {\n" | |
1102 | " major = %u;\n" | |
1103 | " minor = %u;\n" | |
30bdb6e4 | 1104 | " uuid = \"%s\";\n" |
d793d5e1 MD |
1105 | " byte_order = %s;\n" |
1106 | " packet.header := struct {\n" | |
1107 | " uint32_t magic;\n" | |
1ec3f75a | 1108 | " uint8_t uuid[16];\n" |
d793d5e1 | 1109 | " uint32_t stream_id;\n" |
0eb25f58 | 1110 | " };\n" |
d793d5e1 | 1111 | "};\n\n", |
a90917c3 MD |
1112 | lttng_alignof(uint8_t) * CHAR_BIT, |
1113 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1114 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1115 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
1116 | sizeof(unsigned long) * CHAR_BIT, |
1117 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
1118 | CTF_SPEC_MAJOR, |
1119 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
1120 | uuid_s, |
1121 | #ifdef __BIG_ENDIAN | |
1122 | "be" | |
1123 | #else | |
1124 | "le" | |
1125 | #endif | |
1126 | ); | |
1127 | if (ret) | |
1128 | goto end; | |
1129 | ||
99dc9597 MD |
1130 | ret = lttng_metadata_printf(session, |
1131 | "env {\n" | |
a6058143 | 1132 | " hostname = \"%s\";\n" |
c6c9e10f | 1133 | " domain = \"kernel\";\n" |
99dc9597 | 1134 | " sysname = \"%s\";\n" |
c6c9e10f MD |
1135 | " kernel_release = \"%s\";\n" |
1136 | " kernel_version = \"%s\";\n" | |
1137 | " tracer_name = \"lttng-modules\";\n" | |
1138 | " tracer_major = %d;\n" | |
1139 | " tracer_minor = %d;\n" | |
1140 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 1141 | "};\n\n", |
3d0d43db | 1142 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
1143 | utsname()->sysname, |
1144 | utsname()->release, | |
c6c9e10f MD |
1145 | utsname()->version, |
1146 | LTTNG_MODULES_MAJOR_VERSION, | |
1147 | LTTNG_MODULES_MINOR_VERSION, | |
1148 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
1149 | ); |
1150 | if (ret) | |
1151 | goto end; | |
1152 | ||
a3ccff4f MD |
1153 | ret = lttng_metadata_printf(session, |
1154 | "clock {\n" | |
a82c63f1 MD |
1155 | " name = %s;\n", |
1156 | "monotonic" | |
1157 | ); | |
1158 | if (ret) | |
1159 | goto end; | |
1160 | ||
1161 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1162 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1163 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1164 | clock_uuid_s |
1165 | ); | |
1166 | if (ret) | |
1167 | goto end; | |
1168 | } | |
1169 | ||
1170 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1171 | " description = \"Monotonic Clock\";\n" |
1172 | " freq = %llu; /* Frequency, in Hz */\n" | |
1173 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1174 | " offset = %llu;\n" | |
1175 | "};\n\n", | |
a3ccff4f MD |
1176 | (unsigned long long) trace_clock_freq(), |
1177 | (unsigned long long) measure_clock_offset() | |
1178 | ); | |
1179 | if (ret) | |
1180 | goto end; | |
1181 | ||
1182 | ret = lttng_metadata_printf(session, | |
1183 | "typealias integer {\n" | |
1184 | " size = 27; align = 1; signed = false;\n" | |
1185 | " map = clock.monotonic.value;\n" | |
1186 | "} := uint27_clock_monotonic_t;\n" | |
1187 | "\n" | |
1188 | "typealias integer {\n" | |
1189 | " size = 32; align = %u; signed = false;\n" | |
1190 | " map = clock.monotonic.value;\n" | |
1191 | "} := uint32_clock_monotonic_t;\n" | |
1192 | "\n" | |
1193 | "typealias integer {\n" | |
1194 | " size = 64; align = %u; signed = false;\n" | |
1195 | " map = clock.monotonic.value;\n" | |
1196 | "} := uint64_clock_monotonic_t;\n\n", | |
1197 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1198 | lttng_alignof(uint64_t) * CHAR_BIT | |
1199 | ); | |
1200 | if (ret) | |
1201 | goto end; | |
1202 | ||
a90917c3 | 1203 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1204 | if (ret) |
1205 | goto end; | |
1206 | ||
a90917c3 | 1207 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1208 | if (ret) |
1209 | goto end; | |
1210 | ||
c099397a MD |
1211 | skip_session: |
1212 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1213 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1214 | if (ret) |
1215 | goto end; | |
1216 | } | |
1217 | ||
1218 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1219 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1220 | if (ret) |
1221 | goto end; | |
1222 | } | |
1223 | session->metadata_dumped = 1; | |
1224 | end: | |
1225 | return ret; | |
1226 | } | |
1227 | ||
c0e31d2e | 1228 | /** |
a90917c3 | 1229 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1230 | * @transport: transport structure |
1231 | * | |
1232 | * Registers a transport which can be used as output to extract the data out of | |
1233 | * LTTng. The module calling this registration function must ensure that no | |
1234 | * trap-inducing code will be executed by the transport functions. E.g. | |
1235 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1236 | * is made visible to the transport function. This registration acts as a | |
1237 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1238 | * after its registration must it synchronize the TLBs. | |
1239 | */ | |
a90917c3 | 1240 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1241 | { |
1242 | /* | |
1243 | * Make sure no page fault can be triggered by the module about to be | |
1244 | * registered. We deal with this here so we don't have to call | |
1245 | * vmalloc_sync_all() in each module's init. | |
1246 | */ | |
6d2a620c | 1247 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1248 | |
1249 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1250 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1251 | mutex_unlock(&sessions_mutex); |
1252 | } | |
a90917c3 | 1253 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1254 | |
1255 | /** | |
a90917c3 | 1256 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1257 | * @transport: transport structure |
1258 | */ | |
a90917c3 | 1259 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1260 | { |
1261 | mutex_lock(&sessions_mutex); | |
1262 | list_del(&transport->node); | |
1263 | mutex_unlock(&sessions_mutex); | |
1264 | } | |
a90917c3 | 1265 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 1266 | |
a90917c3 | 1267 | static int __init lttng_events_init(void) |
4e3c1b9b | 1268 | { |
1c25284c MD |
1269 | int ret; |
1270 | ||
453b2495 JD |
1271 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
1272 | if (ret) | |
1273 | return ret; | |
1274 | ||
20591cf7 MD |
1275 | ret = lttng_tracepoint_init(); |
1276 | if (ret) | |
1277 | return ret; | |
a90917c3 | 1278 | event_cache = KMEM_CACHE(lttng_event, 0); |
20591cf7 MD |
1279 | if (!event_cache) { |
1280 | ret = -ENOMEM; | |
1281 | goto error_kmem; | |
1282 | } | |
80996790 | 1283 | ret = lttng_abi_init(); |
02119ee5 MD |
1284 | if (ret) |
1285 | goto error_abi; | |
0c956676 MD |
1286 | ret = lttng_logger_init(); |
1287 | if (ret) | |
1288 | goto error_logger; | |
4e3c1b9b | 1289 | return 0; |
0c956676 MD |
1290 | |
1291 | error_logger: | |
1292 | lttng_abi_exit(); | |
02119ee5 | 1293 | error_abi: |
1c25284c | 1294 | kmem_cache_destroy(event_cache); |
20591cf7 MD |
1295 | error_kmem: |
1296 | lttng_tracepoint_exit(); | |
1c25284c | 1297 | return ret; |
4e3c1b9b MD |
1298 | } |
1299 | ||
a90917c3 | 1300 | module_init(lttng_events_init); |
11b5a3c2 | 1301 | |
a90917c3 | 1302 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 1303 | { |
a90917c3 | 1304 | struct lttng_session *session, *tmpsession; |
92e94819 | 1305 | |
0c956676 | 1306 | lttng_logger_exit(); |
80996790 | 1307 | lttng_abi_exit(); |
92e94819 | 1308 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 1309 | lttng_session_destroy(session); |
11b5a3c2 | 1310 | kmem_cache_destroy(event_cache); |
20591cf7 | 1311 | lttng_tracepoint_exit(); |
4e3c1b9b | 1312 | } |
92e94819 | 1313 | |
a90917c3 | 1314 | module_exit(lttng_events_exit); |
11b5a3c2 | 1315 | |
92e94819 MD |
1316 | MODULE_LICENSE("GPL and additional rights"); |
1317 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
1318 | MODULE_DESCRIPTION("LTTng Events"); | |
9a9973ef MD |
1319 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
1320 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
309370e2 MD |
1321 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
1322 | LTTNG_MODULES_EXTRAVERSION); |