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 | ||
66861b2e MD |
23 | /* |
24 | * This page_alloc.h wrapper needs to be included before gfpflags.h because it | |
25 | * overrides a function with a define. | |
26 | */ | |
27 | #include "wrapper/page_alloc.h" | |
28 | ||
4e3c1b9b | 29 | #include <linux/module.h> |
c0e31d2e MD |
30 | #include <linux/list.h> |
31 | #include <linux/mutex.h> | |
32 | #include <linux/sched.h> | |
11b5a3c2 | 33 | #include <linux/slab.h> |
c099397a | 34 | #include <linux/jiffies.h> |
99dc9597 | 35 | #include <linux/utsname.h> |
abc0446a | 36 | #include <linux/err.h> |
b02a8b73 ML |
37 | #include <linux/vmalloc.h> |
38 | ||
a864fb02 | 39 | #include "wrapper/uuid.h" |
b13f3ebe | 40 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
a82c63f1 | 41 | #include "wrapper/random.h" |
3a523f5b | 42 | #include "wrapper/tracepoint.h" |
b8590f40 | 43 | #include "lttng-kernel-version.h" |
a90917c3 MD |
44 | #include "lttng-events.h" |
45 | #include "lttng-tracer.h" | |
6dccd6c1 | 46 | #include "lttng-abi-old.h" |
180243e7 | 47 | #include "wrapper/vzalloc.h" |
4e3c1b9b | 48 | |
d83004aa JD |
49 | #define METADATA_CACHE_DEFAULT_SIZE 4096 |
50 | ||
4e3c1b9b | 51 | static LIST_HEAD(sessions); |
a90917c3 | 52 | static LIST_HEAD(lttng_transport_list); |
d83004aa JD |
53 | /* |
54 | * Protect the sessions and metadata caches. | |
55 | */ | |
4e3c1b9b MD |
56 | static DEFINE_MUTEX(sessions_mutex); |
57 | static struct kmem_cache *event_cache; | |
58 | ||
a90917c3 MD |
59 | static void _lttng_event_destroy(struct lttng_event *event); |
60 | static void _lttng_channel_destroy(struct lttng_channel *chan); | |
61 | static int _lttng_event_unregister(struct lttng_event *event); | |
c099397a | 62 | static |
a90917c3 MD |
63 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
64 | struct lttng_channel *chan, | |
65 | struct lttng_event *event); | |
c099397a | 66 | static |
a90917c3 | 67 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
d83004aa JD |
68 | static |
69 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream); | |
c099397a | 70 | |
c099397a | 71 | void synchronize_trace(void) |
abcca994 MD |
72 | { |
73 | synchronize_sched(); | |
b8590f40 MD |
74 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
75 | #ifdef CONFIG_PREEMPT_RT_FULL | |
76 | synchronize_rcu(); | |
77 | #endif | |
78 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ | |
abcca994 MD |
79 | #ifdef CONFIG_PREEMPT_RT |
80 | synchronize_rcu(); | |
81 | #endif | |
b8590f40 | 82 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
abcca994 MD |
83 | } |
84 | ||
a90917c3 | 85 | struct lttng_session *lttng_session_create(void) |
4e3c1b9b | 86 | { |
a90917c3 | 87 | struct lttng_session *session; |
d83004aa | 88 | struct lttng_metadata_cache *metadata_cache; |
4e3c1b9b MD |
89 | |
90 | mutex_lock(&sessions_mutex); | |
a90917c3 | 91 | session = kzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
4e3c1b9b | 92 | if (!session) |
d83004aa | 93 | goto err; |
4e3c1b9b | 94 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 95 | INIT_LIST_HEAD(&session->events); |
d793d5e1 | 96 | uuid_le_gen(&session->uuid); |
d83004aa JD |
97 | |
98 | metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache), | |
99 | GFP_KERNEL); | |
100 | if (!metadata_cache) | |
101 | goto err_free_session; | |
180243e7 | 102 | metadata_cache->data = lttng_vzalloc(METADATA_CACHE_DEFAULT_SIZE); |
d83004aa JD |
103 | if (!metadata_cache->data) |
104 | goto err_free_cache; | |
105 | metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE; | |
106 | kref_init(&metadata_cache->refcount); | |
54028e45 | 107 | mutex_init(&metadata_cache->lock); |
d83004aa JD |
108 | session->metadata_cache = metadata_cache; |
109 | INIT_LIST_HEAD(&metadata_cache->metadata_stream); | |
9b8e91ac MD |
110 | memcpy(&metadata_cache->uuid, &session->uuid, |
111 | sizeof(metadata_cache->uuid)); | |
4e3c1b9b MD |
112 | list_add(&session->list, &sessions); |
113 | mutex_unlock(&sessions_mutex); | |
114 | return session; | |
d83004aa JD |
115 | |
116 | err_free_cache: | |
117 | kfree(metadata_cache); | |
118 | err_free_session: | |
119 | kfree(session); | |
120 | err: | |
121 | mutex_unlock(&sessions_mutex); | |
122 | return NULL; | |
123 | } | |
124 | ||
125 | void metadata_cache_destroy(struct kref *kref) | |
126 | { | |
127 | struct lttng_metadata_cache *cache = | |
128 | container_of(kref, struct lttng_metadata_cache, refcount); | |
b02a8b73 | 129 | vfree(cache->data); |
d83004aa | 130 | kfree(cache); |
4e3c1b9b MD |
131 | } |
132 | ||
a90917c3 | 133 | void lttng_session_destroy(struct lttng_session *session) |
4e3c1b9b | 134 | { |
a90917c3 MD |
135 | struct lttng_channel *chan, *tmpchan; |
136 | struct lttng_event *event, *tmpevent; | |
d83004aa | 137 | struct lttng_metadata_stream *metadata_stream; |
dda6a249 | 138 | int ret; |
4e3c1b9b MD |
139 | |
140 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 141 | ACCESS_ONCE(session->active) = 0; |
1ec65de1 MD |
142 | list_for_each_entry(chan, &session->chan, list) { |
143 | ret = lttng_syscalls_unregister(chan); | |
144 | WARN_ON(ret); | |
145 | } | |
dda6a249 | 146 | list_for_each_entry(event, &session->events, list) { |
a90917c3 | 147 | ret = _lttng_event_unregister(event); |
dda6a249 MD |
148 | WARN_ON(ret); |
149 | } | |
abcca994 | 150 | synchronize_trace(); /* Wait for in-flight events to complete */ |
4e3c1b9b | 151 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
a90917c3 | 152 | _lttng_event_destroy(event); |
d83004aa JD |
153 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { |
154 | BUG_ON(chan->channel_type == METADATA_CHANNEL); | |
a90917c3 | 155 | _lttng_channel_destroy(chan); |
d83004aa JD |
156 | } |
157 | list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) | |
158 | _lttng_metadata_channel_hangup(metadata_stream); | |
159 | kref_put(&session->metadata_cache->refcount, metadata_cache_destroy); | |
4e3c1b9b MD |
160 | list_del(&session->list); |
161 | mutex_unlock(&sessions_mutex); | |
162 | kfree(session); | |
163 | } | |
164 | ||
a90917c3 | 165 | int lttng_session_enable(struct lttng_session *session) |
c0e31d2e MD |
166 | { |
167 | int ret = 0; | |
a90917c3 | 168 | struct lttng_channel *chan; |
c0e31d2e MD |
169 | |
170 | mutex_lock(&sessions_mutex); | |
171 | if (session->active) { | |
172 | ret = -EBUSY; | |
173 | goto end; | |
174 | } | |
c099397a MD |
175 | |
176 | /* | |
177 | * Snapshot the number of events per channel to know the type of header | |
178 | * we need to use. | |
179 | */ | |
180 | list_for_each_entry(chan, &session->chan, list) { | |
181 | if (chan->header_type) | |
182 | continue; /* don't change it if session stop/restart */ | |
183 | if (chan->free_event_id < 31) | |
184 | chan->header_type = 1; /* compact */ | |
185 | else | |
186 | chan->header_type = 2; /* large */ | |
187 | } | |
188 | ||
52fc2e1f | 189 | ACCESS_ONCE(session->active) = 1; |
8070f5c0 | 190 | ACCESS_ONCE(session->been_active) = 1; |
a90917c3 | 191 | ret = _lttng_session_metadata_statedump(session); |
c337ddc2 MD |
192 | if (ret) { |
193 | ACCESS_ONCE(session->active) = 0; | |
194 | goto end; | |
195 | } | |
196 | ret = lttng_statedump_start(session); | |
360f38ea | 197 | if (ret) |
c099397a | 198 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
199 | end: |
200 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 201 | return ret; |
c0e31d2e MD |
202 | } |
203 | ||
a90917c3 | 204 | int lttng_session_disable(struct lttng_session *session) |
c0e31d2e MD |
205 | { |
206 | int ret = 0; | |
207 | ||
208 | mutex_lock(&sessions_mutex); | |
209 | if (!session->active) { | |
210 | ret = -EBUSY; | |
211 | goto end; | |
212 | } | |
52fc2e1f | 213 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
214 | end: |
215 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 216 | return ret; |
c0e31d2e MD |
217 | } |
218 | ||
a90917c3 | 219 | int lttng_channel_enable(struct lttng_channel *channel) |
e64957da MD |
220 | { |
221 | int old; | |
222 | ||
d83004aa | 223 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 224 | return -EPERM; |
e64957da MD |
225 | old = xchg(&channel->enabled, 1); |
226 | if (old) | |
227 | return -EEXIST; | |
228 | return 0; | |
229 | } | |
230 | ||
a90917c3 | 231 | int lttng_channel_disable(struct lttng_channel *channel) |
e64957da MD |
232 | { |
233 | int old; | |
234 | ||
d83004aa | 235 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 236 | return -EPERM; |
e64957da MD |
237 | old = xchg(&channel->enabled, 0); |
238 | if (!old) | |
239 | return -EEXIST; | |
240 | return 0; | |
241 | } | |
242 | ||
a90917c3 | 243 | int lttng_event_enable(struct lttng_event *event) |
e64957da MD |
244 | { |
245 | int old; | |
246 | ||
d83004aa | 247 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 248 | return -EPERM; |
e64957da MD |
249 | old = xchg(&event->enabled, 1); |
250 | if (old) | |
251 | return -EEXIST; | |
252 | return 0; | |
253 | } | |
254 | ||
a90917c3 | 255 | int lttng_event_disable(struct lttng_event *event) |
e64957da MD |
256 | { |
257 | int old; | |
258 | ||
d83004aa | 259 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 260 | return -EPERM; |
e64957da MD |
261 | old = xchg(&event->enabled, 0); |
262 | if (!old) | |
263 | return -EEXIST; | |
264 | return 0; | |
265 | } | |
266 | ||
a90917c3 | 267 | static struct lttng_transport *lttng_transport_find(const char *name) |
f3d01b96 | 268 | { |
a90917c3 | 269 | struct lttng_transport *transport; |
f3d01b96 | 270 | |
a90917c3 | 271 | list_for_each_entry(transport, <tng_transport_list, node) { |
f3d01b96 MD |
272 | if (!strcmp(transport->name, name)) |
273 | return transport; | |
274 | } | |
275 | return NULL; | |
276 | } | |
277 | ||
a90917c3 | 278 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
5dbbdb43 MD |
279 | const char *transport_name, |
280 | void *buf_addr, | |
4e3c1b9b MD |
281 | size_t subbuf_size, size_t num_subbuf, |
282 | unsigned int switch_timer_interval, | |
d83004aa JD |
283 | unsigned int read_timer_interval, |
284 | enum channel_type channel_type) | |
4e3c1b9b | 285 | { |
a90917c3 MD |
286 | struct lttng_channel *chan; |
287 | struct lttng_transport *transport = NULL; | |
4e3c1b9b MD |
288 | |
289 | mutex_lock(&sessions_mutex); | |
d83004aa | 290 | if (session->been_active && channel_type != METADATA_CHANNEL) |
e5382b6d | 291 | goto active; /* Refuse to add channel to active session */ |
a90917c3 | 292 | transport = lttng_transport_find(transport_name); |
f3d01b96 MD |
293 | if (!transport) { |
294 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
295 | transport_name); | |
c0e31d2e | 296 | goto notransport; |
f3d01b96 | 297 | } |
a33c9927 MD |
298 | if (!try_module_get(transport->owner)) { |
299 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
300 | goto notransport; | |
301 | } | |
a90917c3 | 302 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
4e3c1b9b | 303 | if (!chan) |
c0e31d2e | 304 | goto nomem; |
4e3c1b9b | 305 | chan->session = session; |
05d32c64 | 306 | chan->id = session->free_chan_id++; |
3b731ab1 | 307 | chan->ops = &transport->ops; |
125b4df4 MD |
308 | /* |
309 | * Note: the channel creation op already writes into the packet | |
310 | * headers. Therefore the "chan" information used as input | |
311 | * should be already accessible. | |
312 | */ | |
5f5ddf01 MD |
313 | chan->chan = transport->ops.channel_create(transport_name, |
314 | chan, buf_addr, subbuf_size, num_subbuf, | |
315 | switch_timer_interval, read_timer_interval); | |
f3d01b96 MD |
316 | if (!chan->chan) |
317 | goto create_error; | |
e64957da | 318 | chan->enabled = 1; |
a33c9927 | 319 | chan->transport = transport; |
d83004aa | 320 | chan->channel_type = channel_type; |
4e3c1b9b MD |
321 | list_add(&chan->list, &session->chan); |
322 | mutex_unlock(&sessions_mutex); | |
323 | return chan; | |
324 | ||
f3d01b96 MD |
325 | create_error: |
326 | kfree(chan); | |
c0e31d2e | 327 | nomem: |
a33c9927 MD |
328 | if (transport) |
329 | module_put(transport->owner); | |
c0e31d2e | 330 | notransport: |
e5382b6d | 331 | active: |
4e3c1b9b MD |
332 | mutex_unlock(&sessions_mutex); |
333 | return NULL; | |
334 | } | |
335 | ||
336 | /* | |
d83004aa JD |
337 | * Only used internally at session destruction for per-cpu channels, and |
338 | * when metadata channel is released. | |
339 | * Needs to be called with sessions mutex held. | |
4e3c1b9b | 340 | */ |
aa7c23a9 | 341 | static |
a90917c3 | 342 | void _lttng_channel_destroy(struct lttng_channel *chan) |
4e3c1b9b | 343 | { |
11b5a3c2 | 344 | chan->ops->channel_destroy(chan->chan); |
a33c9927 | 345 | module_put(chan->transport->owner); |
4e3c1b9b | 346 | list_del(&chan->list); |
8070f5c0 | 347 | lttng_destroy_context(chan->ctx); |
4e3c1b9b MD |
348 | kfree(chan); |
349 | } | |
350 | ||
d83004aa JD |
351 | void lttng_metadata_channel_destroy(struct lttng_channel *chan) |
352 | { | |
353 | BUG_ON(chan->channel_type != METADATA_CHANNEL); | |
354 | ||
355 | /* Protect the metadata cache with the sessions_mutex. */ | |
356 | mutex_lock(&sessions_mutex); | |
357 | _lttng_channel_destroy(chan); | |
358 | mutex_unlock(&sessions_mutex); | |
359 | } | |
360 | EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy); | |
361 | ||
362 | static | |
363 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream) | |
364 | { | |
365 | stream->finalized = 1; | |
366 | wake_up_interruptible(&stream->read_wait); | |
367 | } | |
368 | ||
e5382b6d MD |
369 | /* |
370 | * Supports event creation while tracing session is active. | |
371 | */ | |
a90917c3 | 372 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
d6d808f3 | 373 | struct lttng_kernel_event *event_param, |
259b6cb3 MD |
374 | void *filter, |
375 | const struct lttng_event_desc *internal_desc) | |
4e3c1b9b | 376 | { |
a90917c3 | 377 | struct lttng_event *event; |
3d084699 | 378 | int ret; |
4e3c1b9b MD |
379 | |
380 | mutex_lock(&sessions_mutex); | |
abc0446a | 381 | if (chan->free_event_id == -1U) { |
4cf0bf51 | 382 | ret = -EMFILE; |
e5382b6d | 383 | goto full; |
abc0446a | 384 | } |
4e3c1b9b | 385 | /* |
dda6a249 MD |
386 | * This is O(n^2) (for each event, the loop is called at event |
387 | * creation). Might require a hash if we have lots of events. | |
4e3c1b9b | 388 | */ |
abc0446a MD |
389 | list_for_each_entry(event, &chan->session->events, list) { |
390 | if (!strcmp(event->desc->name, event_param->name)) { | |
4cf0bf51 | 391 | ret = -EEXIST; |
4e3c1b9b | 392 | goto exist; |
abc0446a MD |
393 | } |
394 | } | |
11b5a3c2 | 395 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
abc0446a | 396 | if (!event) { |
4cf0bf51 | 397 | ret = -ENOMEM; |
4e3c1b9b | 398 | goto cache_error; |
abc0446a | 399 | } |
4e3c1b9b MD |
400 | event->chan = chan; |
401 | event->filter = filter; | |
e5382b6d | 402 | event->id = chan->free_event_id++; |
e64957da | 403 | event->enabled = 1; |
d6d808f3 | 404 | event->instrumentation = event_param->instrumentation; |
a90917c3 | 405 | /* Populate lttng_event structure before tracepoint registration. */ |
e5382b6d | 406 | smp_wmb(); |
d6d808f3 | 407 | switch (event_param->instrumentation) { |
ab2277d6 | 408 | case LTTNG_KERNEL_TRACEPOINT: |
a90917c3 | 409 | event->desc = lttng_event_get(event_param->name); |
abc0446a | 410 | if (!event->desc) { |
4cf0bf51 | 411 | ret = -ENOENT; |
d3dbe23c | 412 | goto register_error; |
abc0446a | 413 | } |
20591cf7 | 414 | ret = lttng_wrapper_tracepoint_probe_register(event->desc->kname, |
d3dbe23c MD |
415 | event->desc->probe_callback, |
416 | event); | |
abc0446a | 417 | if (ret) { |
4cf0bf51 | 418 | ret = -EINVAL; |
11b5a3c2 | 419 | goto register_error; |
abc0446a | 420 | } |
baf20995 | 421 | break; |
ab2277d6 | 422 | case LTTNG_KERNEL_KPROBE: |
30bdb6e4 | 423 | ret = lttng_kprobes_register(event_param->name, |
f17701fb MD |
424 | event_param->u.kprobe.symbol_name, |
425 | event_param->u.kprobe.offset, | |
426 | event_param->u.kprobe.addr, | |
427 | event); | |
abc0446a | 428 | if (ret) { |
4cf0bf51 | 429 | ret = -EINVAL; |
d6d808f3 | 430 | goto register_error; |
abc0446a | 431 | } |
edeb3137 MD |
432 | ret = try_module_get(event->desc->owner); |
433 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 434 | break; |
7371f44c MD |
435 | case LTTNG_KERNEL_KRETPROBE: |
436 | { | |
a90917c3 | 437 | struct lttng_event *event_return; |
7371f44c MD |
438 | |
439 | /* kretprobe defines 2 events */ | |
440 | event_return = | |
441 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
abc0446a | 442 | if (!event_return) { |
4cf0bf51 | 443 | ret = -ENOMEM; |
7371f44c | 444 | goto register_error; |
abc0446a | 445 | } |
7371f44c MD |
446 | event_return->chan = chan; |
447 | event_return->filter = filter; | |
448 | event_return->id = chan->free_event_id++; | |
449 | event_return->enabled = 1; | |
450 | event_return->instrumentation = event_param->instrumentation; | |
451 | /* | |
a90917c3 | 452 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
453 | */ |
454 | smp_wmb(); | |
455 | ret = lttng_kretprobes_register(event_param->name, | |
456 | event_param->u.kretprobe.symbol_name, | |
457 | event_param->u.kretprobe.offset, | |
458 | event_param->u.kretprobe.addr, | |
459 | event, event_return); | |
460 | if (ret) { | |
461 | kmem_cache_free(event_cache, event_return); | |
4cf0bf51 | 462 | ret = -EINVAL; |
7371f44c MD |
463 | goto register_error; |
464 | } | |
465 | /* Take 2 refs on the module: one per event. */ | |
466 | ret = try_module_get(event->desc->owner); | |
467 | WARN_ON_ONCE(!ret); | |
468 | ret = try_module_get(event->desc->owner); | |
469 | WARN_ON_ONCE(!ret); | |
a90917c3 | 470 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c | 471 | event_return); |
abc0446a | 472 | WARN_ON_ONCE(ret > 0); |
7371f44c MD |
473 | if (ret) { |
474 | kmem_cache_free(event_cache, event_return); | |
475 | module_put(event->desc->owner); | |
476 | module_put(event->desc->owner); | |
477 | goto statedump_error; | |
478 | } | |
479 | list_add(&event_return->list, &chan->session->events); | |
480 | break; | |
481 | } | |
ab2277d6 | 482 | case LTTNG_KERNEL_FUNCTION: |
30bdb6e4 | 483 | ret = lttng_ftrace_register(event_param->name, |
e0a7a7c4 MD |
484 | event_param->u.ftrace.symbol_name, |
485 | event); | |
abc0446a | 486 | if (ret) { |
e0a7a7c4 | 487 | goto register_error; |
abc0446a | 488 | } |
edeb3137 MD |
489 | ret = try_module_get(event->desc->owner); |
490 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 491 | break; |
1ec65de1 | 492 | case LTTNG_KERNEL_NOOP: |
259b6cb3 | 493 | event->desc = internal_desc; |
abc0446a | 494 | if (!event->desc) { |
4cf0bf51 | 495 | ret = -EINVAL; |
259b6cb3 | 496 | goto register_error; |
abc0446a | 497 | } |
1ec65de1 | 498 | break; |
baf20995 MD |
499 | default: |
500 | WARN_ON_ONCE(1); | |
4cf0bf51 | 501 | ret = -EINVAL; |
df07930b | 502 | goto register_error; |
baf20995 | 503 | } |
a90917c3 | 504 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
abc0446a MD |
505 | WARN_ON_ONCE(ret > 0); |
506 | if (ret) { | |
c099397a | 507 | goto statedump_error; |
abc0446a | 508 | } |
dda6a249 | 509 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 510 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
511 | return event; |
512 | ||
c099397a | 513 | statedump_error: |
259b6cb3 | 514 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 515 | register_error: |
11b5a3c2 | 516 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
517 | cache_error: |
518 | exist: | |
e5382b6d | 519 | full: |
4e3c1b9b | 520 | mutex_unlock(&sessions_mutex); |
4cf0bf51 | 521 | return ERR_PTR(ret); |
4e3c1b9b MD |
522 | } |
523 | ||
524 | /* | |
525 | * Only used internally at session destruction. | |
526 | */ | |
a90917c3 | 527 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 528 | { |
11b5a3c2 MD |
529 | int ret = -EINVAL; |
530 | ||
38d024ae | 531 | switch (event->instrumentation) { |
ab2277d6 | 532 | case LTTNG_KERNEL_TRACEPOINT: |
20591cf7 | 533 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
85a9ca7f | 534 | event->desc->probe_callback, |
11b5a3c2 MD |
535 | event); |
536 | if (ret) | |
537 | return ret; | |
baf20995 | 538 | break; |
ab2277d6 | 539 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 540 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
541 | ret = 0; |
542 | break; | |
7371f44c MD |
543 | case LTTNG_KERNEL_KRETPROBE: |
544 | lttng_kretprobes_unregister(event); | |
545 | ret = 0; | |
546 | break; | |
ab2277d6 | 547 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
548 | lttng_ftrace_unregister(event); |
549 | ret = 0; | |
550 | break; | |
259b6cb3 MD |
551 | case LTTNG_KERNEL_NOOP: |
552 | ret = 0; | |
553 | break; | |
baf20995 MD |
554 | default: |
555 | WARN_ON_ONCE(1); | |
556 | } | |
dda6a249 MD |
557 | return ret; |
558 | } | |
559 | ||
560 | /* | |
561 | * Only used internally at session destruction. | |
562 | */ | |
be066e6c | 563 | static |
a90917c3 | 564 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 565 | { |
edeb3137 MD |
566 | switch (event->instrumentation) { |
567 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 568 | lttng_event_put(event->desc); |
edeb3137 MD |
569 | break; |
570 | case LTTNG_KERNEL_KPROBE: | |
571 | module_put(event->desc->owner); | |
572 | lttng_kprobes_destroy_private(event); | |
573 | break; | |
7371f44c MD |
574 | case LTTNG_KERNEL_KRETPROBE: |
575 | module_put(event->desc->owner); | |
576 | lttng_kretprobes_destroy_private(event); | |
577 | break; | |
edeb3137 MD |
578 | case LTTNG_KERNEL_FUNCTION: |
579 | module_put(event->desc->owner); | |
580 | lttng_ftrace_destroy_private(event); | |
581 | break; | |
259b6cb3 MD |
582 | case LTTNG_KERNEL_NOOP: |
583 | break; | |
edeb3137 MD |
584 | default: |
585 | WARN_ON_ONCE(1); | |
586 | } | |
dda6a249 | 587 | list_del(&event->list); |
8070f5c0 | 588 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 589 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
590 | } |
591 | ||
1ec3f75a | 592 | /* |
d83004aa JD |
593 | * Serialize at most one packet worth of metadata into a metadata |
594 | * channel. | |
54028e45 MD |
595 | * We grab the metadata cache mutex to get exclusive access to our metadata |
596 | * buffer and to the metadata cache. Exclusive access to the metadata buffer | |
597 | * allows us to do racy operations such as looking for remaining space left in | |
598 | * packet and write, since mutual exclusion protects us from concurrent writes. | |
599 | * Mutual exclusion on the metadata cache allow us to read the cache content | |
600 | * without racing against reallocation of the cache by updates. | |
35097f36 JD |
601 | * Returns the number of bytes written in the channel, 0 if no data |
602 | * was written and a negative value on error. | |
1ec3f75a | 603 | */ |
b3b8072b MD |
604 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
605 | struct channel *chan) | |
d83004aa JD |
606 | { |
607 | struct lib_ring_buffer_ctx ctx; | |
608 | int ret = 0; | |
609 | size_t len, reserve_len; | |
610 | ||
f613e3e6 | 611 | /* |
54028e45 MD |
612 | * Ensure we support mutiple get_next / put sequences followed by |
613 | * put_next. The metadata cache lock protects reading the metadata | |
614 | * cache. It can indeed be read concurrently by "get_next_subbuf" and | |
615 | * "flush" operations on the buffer invoked by different processes. | |
616 | * Moreover, since the metadata cache memory can be reallocated, we | |
617 | * need to have exclusive access against updates even though we only | |
618 | * read it. | |
f613e3e6 | 619 | */ |
54028e45 | 620 | mutex_lock(&stream->metadata_cache->lock); |
f613e3e6 MD |
621 | WARN_ON(stream->metadata_in < stream->metadata_out); |
622 | if (stream->metadata_in != stream->metadata_out) | |
b773bad5 | 623 | goto end; |
f613e3e6 | 624 | |
d83004aa | 625 | len = stream->metadata_cache->metadata_written - |
f613e3e6 | 626 | stream->metadata_in; |
9de2c215 | 627 | if (!len) |
b773bad5 | 628 | goto end; |
d83004aa | 629 | reserve_len = min_t(size_t, |
b3b8072b | 630 | stream->transport->ops.packet_avail_size(chan), |
d83004aa | 631 | len); |
b3b8072b | 632 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
d83004aa JD |
633 | sizeof(char), -1); |
634 | /* | |
635 | * If reservation failed, return an error to the caller. | |
636 | */ | |
b3b8072b | 637 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
d83004aa JD |
638 | if (ret != 0) { |
639 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); | |
640 | goto end; | |
641 | } | |
b3b8072b | 642 | stream->transport->ops.event_write(&ctx, |
f613e3e6 | 643 | stream->metadata_cache->data + stream->metadata_in, |
d83004aa | 644 | reserve_len); |
b3b8072b | 645 | stream->transport->ops.event_commit(&ctx); |
f613e3e6 | 646 | stream->metadata_in += reserve_len; |
d83004aa JD |
647 | ret = reserve_len; |
648 | ||
649 | end: | |
54028e45 | 650 | mutex_unlock(&stream->metadata_cache->lock); |
d83004aa JD |
651 | return ret; |
652 | } | |
653 | ||
654 | /* | |
655 | * Write the metadata to the metadata cache. | |
656 | * Must be called with sessions_mutex held. | |
54028e45 MD |
657 | * The metadata cache lock protects us from concurrent read access from |
658 | * thread outputting metadata content to ring buffer. | |
d83004aa | 659 | */ |
a90917c3 | 660 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
661 | const char *fmt, ...) |
662 | { | |
c099397a | 663 | char *str; |
d83004aa | 664 | size_t len; |
c099397a | 665 | va_list ap; |
d83004aa | 666 | struct lttng_metadata_stream *stream; |
c099397a MD |
667 | |
668 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
669 | ||
670 | va_start(ap, fmt); | |
671 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
672 | va_end(ap); | |
673 | if (!str) | |
674 | return -ENOMEM; | |
675 | ||
1ec3f75a | 676 | len = strlen(str); |
54028e45 | 677 | mutex_lock(&session->metadata_cache->lock); |
d83004aa JD |
678 | if (session->metadata_cache->metadata_written + len > |
679 | session->metadata_cache->cache_alloc) { | |
680 | char *tmp_cache_realloc; | |
681 | unsigned int tmp_cache_alloc_size; | |
682 | ||
683 | tmp_cache_alloc_size = max_t(unsigned int, | |
684 | session->metadata_cache->cache_alloc + len, | |
685 | session->metadata_cache->cache_alloc << 1); | |
180243e7 | 686 | tmp_cache_realloc = lttng_vzalloc(tmp_cache_alloc_size); |
d83004aa JD |
687 | if (!tmp_cache_realloc) |
688 | goto err; | |
b02a8b73 ML |
689 | if (session->metadata_cache->data) { |
690 | memcpy(tmp_cache_realloc, | |
691 | session->metadata_cache->data, | |
692 | session->metadata_cache->cache_alloc); | |
693 | vfree(session->metadata_cache->data); | |
694 | } | |
695 | ||
d83004aa JD |
696 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; |
697 | session->metadata_cache->data = tmp_cache_realloc; | |
c099397a | 698 | } |
d83004aa JD |
699 | memcpy(session->metadata_cache->data + |
700 | session->metadata_cache->metadata_written, | |
701 | str, len); | |
702 | session->metadata_cache->metadata_written += len; | |
54028e45 | 703 | mutex_unlock(&session->metadata_cache->lock); |
c099397a | 704 | kfree(str); |
d83004aa JD |
705 | |
706 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) | |
707 | wake_up_interruptible(&stream->read_wait); | |
708 | ||
709 | return 0; | |
710 | ||
711 | err: | |
54028e45 | 712 | mutex_unlock(&session->metadata_cache->lock); |
d83004aa JD |
713 | kfree(str); |
714 | return -ENOMEM; | |
c099397a MD |
715 | } |
716 | ||
d83004aa JD |
717 | /* |
718 | * Must be called with sessions_mutex held. | |
719 | */ | |
c099397a | 720 | static |
a90917c3 | 721 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 722 | const struct lttng_event_field *field) |
c099397a | 723 | { |
c099397a | 724 | int ret = 0; |
c099397a | 725 | |
8070f5c0 MD |
726 | switch (field->type.atype) { |
727 | case atype_integer: | |
728 | ret = lttng_metadata_printf(session, | |
244465ab | 729 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
730 | field->type.u.basic.integer.size, |
731 | field->type.u.basic.integer.alignment, | |
732 | field->type.u.basic.integer.signedness, | |
733 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
734 | ? "none" | |
735 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
736 | ? "UTF8" | |
737 | : "ASCII", | |
738 | field->type.u.basic.integer.base, | |
c099397a | 739 | #ifdef __BIG_ENDIAN |
8070f5c0 | 740 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 741 | #else |
8070f5c0 | 742 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 743 | #endif |
8070f5c0 MD |
744 | field->name); |
745 | break; | |
746 | case atype_enum: | |
747 | ret = lttng_metadata_printf(session, | |
244465ab | 748 | " %s _%s;\n", |
8070f5c0 MD |
749 | field->type.u.basic.enumeration.name, |
750 | field->name); | |
751 | break; | |
752 | case atype_array: | |
753 | { | |
754 | const struct lttng_basic_type *elem_type; | |
755 | ||
756 | elem_type = &field->type.u.array.elem_type; | |
757 | ret = lttng_metadata_printf(session, | |
244465ab | 758 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
759 | elem_type->u.basic.integer.size, |
760 | elem_type->u.basic.integer.alignment, | |
761 | elem_type->u.basic.integer.signedness, | |
762 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
763 | ? "none" | |
764 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
765 | ? "UTF8" | |
766 | : "ASCII", | |
767 | elem_type->u.basic.integer.base, | |
8fa75f34 | 768 | #ifdef __BIG_ENDIAN |
8070f5c0 | 769 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 770 | #else |
8070f5c0 | 771 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 772 | #endif |
8070f5c0 MD |
773 | field->name, field->type.u.array.length); |
774 | break; | |
775 | } | |
776 | case atype_sequence: | |
777 | { | |
778 | const struct lttng_basic_type *elem_type; | |
779 | const struct lttng_basic_type *length_type; | |
780 | ||
781 | elem_type = &field->type.u.sequence.elem_type; | |
782 | length_type = &field->type.u.sequence.length_type; | |
783 | ret = lttng_metadata_printf(session, | |
784 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 785 | length_type->u.basic.integer.size, |
32257272 | 786 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
787 | length_type->u.basic.integer.signedness, |
788 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
789 | ? "none" | |
0635cdd4 | 790 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 791 | ? "UTF8" |
0635cdd4 | 792 | : "ASCII"), |
8070f5c0 | 793 | length_type->u.basic.integer.base, |
e0a7a7c4 | 794 | #ifdef __BIG_ENDIAN |
8070f5c0 | 795 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 796 | #else |
0635cdd4 | 797 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 798 | #endif |
27d2368e MD |
799 | field->name); |
800 | if (ret) | |
801 | return ret; | |
802 | ||
803 | ret = lttng_metadata_printf(session, | |
244465ab | 804 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 805 | elem_type->u.basic.integer.size, |
32257272 | 806 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
807 | elem_type->u.basic.integer.signedness, |
808 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
809 | ? "none" | |
0635cdd4 | 810 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 811 | ? "UTF8" |
0635cdd4 | 812 | : "ASCII"), |
8070f5c0 | 813 | elem_type->u.basic.integer.base, |
8fa75f34 | 814 | #ifdef __BIG_ENDIAN |
8070f5c0 | 815 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 816 | #else |
8070f5c0 | 817 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 818 | #endif |
8070f5c0 | 819 | field->name, |
27d2368e | 820 | field->name); |
8070f5c0 MD |
821 | break; |
822 | } | |
c099397a | 823 | |
8070f5c0 MD |
824 | case atype_string: |
825 | /* Default encoding is UTF8 */ | |
826 | ret = lttng_metadata_printf(session, | |
244465ab | 827 | " string%s _%s;\n", |
8070f5c0 MD |
828 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
829 | " { encoding = ASCII; }" : "", | |
830 | field->name); | |
831 | break; | |
832 | default: | |
833 | WARN_ON_ONCE(1); | |
834 | return -EINVAL; | |
835 | } | |
836 | return ret; | |
837 | } | |
838 | ||
839 | static | |
a90917c3 | 840 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
841 | struct lttng_ctx *ctx) |
842 | { | |
843 | int ret = 0; | |
844 | int i; | |
845 | ||
846 | if (!ctx) | |
847 | return 0; | |
848 | for (i = 0; i < ctx->nr_fields; i++) { | |
849 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
850 | ||
a90917c3 | 851 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
852 | if (ret) |
853 | return ret; | |
854 | } | |
855 | return ret; | |
856 | } | |
857 | ||
858 | static | |
a90917c3 MD |
859 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
860 | struct lttng_event *event) | |
8070f5c0 MD |
861 | { |
862 | const struct lttng_event_desc *desc = event->desc; | |
863 | int ret = 0; | |
864 | int i; | |
865 | ||
866 | for (i = 0; i < desc->nr_fields; i++) { | |
867 | const struct lttng_event_field *field = &desc->fields[i]; | |
868 | ||
a90917c3 | 869 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
870 | if (ret) |
871 | return ret; | |
c099397a MD |
872 | } |
873 | return ret; | |
874 | } | |
875 | ||
d83004aa JD |
876 | /* |
877 | * Must be called with sessions_mutex held. | |
878 | */ | |
c099397a | 879 | static |
a90917c3 MD |
880 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
881 | struct lttng_channel *chan, | |
882 | struct lttng_event *event) | |
c099397a MD |
883 | { |
884 | int ret = 0; | |
885 | ||
886 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
887 | return 0; | |
d83004aa | 888 | if (chan->channel_type == METADATA_CHANNEL) |
c099397a MD |
889 | return 0; |
890 | ||
891 | ret = lttng_metadata_printf(session, | |
892 | "event {\n" | |
ae734547 | 893 | " name = \"%s\";\n" |
c099397a | 894 | " id = %u;\n" |
b9074a1b | 895 | " stream_id = %u;\n", |
c099397a MD |
896 | event->desc->name, |
897 | event->id, | |
898 | event->chan->id); | |
899 | if (ret) | |
900 | goto end; | |
901 | ||
b9074a1b MD |
902 | if (event->ctx) { |
903 | ret = lttng_metadata_printf(session, | |
904 | " context := struct {\n"); | |
905 | if (ret) | |
906 | goto end; | |
907 | } | |
a90917c3 | 908 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
909 | if (ret) |
910 | goto end; | |
b9074a1b MD |
911 | if (event->ctx) { |
912 | ret = lttng_metadata_printf(session, | |
913 | " };\n"); | |
914 | if (ret) | |
915 | goto end; | |
916 | } | |
8070f5c0 MD |
917 | |
918 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
919 | " fields := struct {\n" |
920 | ); | |
921 | if (ret) | |
922 | goto end; | |
923 | ||
a90917c3 | 924 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
925 | if (ret) |
926 | goto end; | |
927 | ||
928 | /* | |
929 | * LTTng space reservation can only reserve multiples of the | |
930 | * byte size. | |
931 | */ | |
932 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
933 | " };\n" |
934 | "};\n\n"); | |
c099397a MD |
935 | if (ret) |
936 | goto end; | |
937 | ||
c099397a MD |
938 | event->metadata_dumped = 1; |
939 | end: | |
940 | return ret; | |
941 | ||
942 | } | |
943 | ||
d83004aa JD |
944 | /* |
945 | * Must be called with sessions_mutex held. | |
946 | */ | |
c099397a | 947 | static |
a90917c3 MD |
948 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
949 | struct lttng_channel *chan) | |
c099397a MD |
950 | { |
951 | int ret = 0; | |
952 | ||
953 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
954 | return 0; | |
d83004aa JD |
955 | |
956 | if (chan->channel_type == METADATA_CHANNEL) | |
c099397a MD |
957 | return 0; |
958 | ||
959 | WARN_ON_ONCE(!chan->header_type); | |
960 | ret = lttng_metadata_printf(session, | |
961 | "stream {\n" | |
962 | " id = %u;\n" | |
9115fbdc | 963 | " event.header := %s;\n" |
b9074a1b | 964 | " packet.context := struct packet_context;\n", |
c099397a MD |
965 | chan->id, |
966 | chan->header_type == 1 ? "struct event_header_compact" : | |
967 | "struct event_header_large"); | |
968 | if (ret) | |
969 | goto end; | |
970 | ||
b9074a1b MD |
971 | if (chan->ctx) { |
972 | ret = lttng_metadata_printf(session, | |
973 | " event.context := struct {\n"); | |
974 | if (ret) | |
975 | goto end; | |
976 | } | |
a90917c3 | 977 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
978 | if (ret) |
979 | goto end; | |
b9074a1b MD |
980 | if (chan->ctx) { |
981 | ret = lttng_metadata_printf(session, | |
982 | " };\n"); | |
983 | if (ret) | |
984 | goto end; | |
985 | } | |
8070f5c0 MD |
986 | |
987 | ret = lttng_metadata_printf(session, | |
b9074a1b | 988 | "};\n\n"); |
8070f5c0 | 989 | |
c099397a MD |
990 | chan->metadata_dumped = 1; |
991 | end: | |
992 | return ret; | |
993 | } | |
994 | ||
d83004aa JD |
995 | /* |
996 | * Must be called with sessions_mutex held. | |
997 | */ | |
9115fbdc | 998 | static |
a90917c3 | 999 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
1000 | { |
1001 | return lttng_metadata_printf(session, | |
1002 | "struct packet_context {\n" | |
a3ccff4f MD |
1003 | " uint64_clock_monotonic_t timestamp_begin;\n" |
1004 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
1005 | " uint64_t content_size;\n" |
1006 | " uint64_t packet_size;\n" | |
a9afe705 | 1007 | " unsigned long events_discarded;\n" |
9115fbdc | 1008 | " uint32_t cpu_id;\n" |
c6dfdf6f | 1009 | "};\n\n" |
9115fbdc MD |
1010 | ); |
1011 | } | |
1012 | ||
1013 | /* | |
1014 | * Compact header: | |
1015 | * id: range: 0 - 30. | |
1016 | * id 31 is reserved to indicate an extended header. | |
1017 | * | |
1018 | * Large header: | |
1019 | * id: range: 0 - 65534. | |
1020 | * id 65535 is reserved to indicate an extended header. | |
d83004aa JD |
1021 | * |
1022 | * Must be called with sessions_mutex held. | |
9115fbdc MD |
1023 | */ |
1024 | static | |
a90917c3 | 1025 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
1026 | { |
1027 | return lttng_metadata_printf(session, | |
1028 | "struct event_header_compact {\n" | |
1029 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
1030 | " variant <id> {\n" | |
1031 | " struct {\n" | |
a3ccff4f | 1032 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1033 | " } compact;\n" |
1034 | " struct {\n" | |
1035 | " uint32_t id;\n" | |
a3ccff4f | 1036 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1037 | " } extended;\n" |
1038 | " } v;\n" | |
1039 | "} align(%u);\n" | |
1040 | "\n" | |
1041 | "struct event_header_large {\n" | |
1042 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
1043 | " variant <id> {\n" | |
1044 | " struct {\n" | |
a3ccff4f | 1045 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1046 | " } compact;\n" |
1047 | " struct {\n" | |
1048 | " uint32_t id;\n" | |
a3ccff4f | 1049 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1050 | " } extended;\n" |
1051 | " } v;\n" | |
1052 | "} align(%u);\n\n", | |
a90917c3 MD |
1053 | lttng_alignof(uint32_t) * CHAR_BIT, |
1054 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
1055 | ); |
1056 | } | |
1057 | ||
a3ccff4f MD |
1058 | /* |
1059 | * Approximation of NTP time of day to clock monotonic correlation, | |
1060 | * taken at start of trace. | |
1061 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
1062 | * in future versions. | |
1063 | */ | |
1064 | static | |
1065 | uint64_t measure_clock_offset(void) | |
1066 | { | |
1067 | uint64_t offset, monotonic[2], realtime; | |
1068 | struct timespec rts = { 0, 0 }; | |
1069 | unsigned long flags; | |
1070 | ||
1071 | /* Disable interrupts to increase correlation precision. */ | |
1072 | local_irq_save(flags); | |
1073 | monotonic[0] = trace_clock_read64(); | |
1074 | getnstimeofday(&rts); | |
1075 | monotonic[1] = trace_clock_read64(); | |
1076 | local_irq_restore(flags); | |
1077 | ||
1078 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 1079 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
1080 | realtime += rts.tv_nsec; |
1081 | offset = realtime - offset; | |
1082 | return offset; | |
1083 | } | |
1084 | ||
c099397a MD |
1085 | /* |
1086 | * Output metadata into this session's metadata buffers. | |
d83004aa | 1087 | * Must be called with sessions_mutex held. |
c099397a MD |
1088 | */ |
1089 | static | |
a90917c3 | 1090 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 1091 | { |
30bdb6e4 | 1092 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 1093 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
1094 | struct lttng_channel *chan; |
1095 | struct lttng_event *event; | |
c099397a MD |
1096 | int ret = 0; |
1097 | ||
1098 | if (!ACCESS_ONCE(session->active)) | |
1099 | return 0; | |
1100 | if (session->metadata_dumped) | |
1101 | goto skip_session; | |
c099397a | 1102 | |
d793d5e1 | 1103 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
1104 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
1105 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
1106 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
1107 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
1108 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
1109 | |
1110 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1111 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
1112 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
1113 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
1114 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 1115 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
1116 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
1117 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
1118 | "\n" |
1119 | "trace {\n" | |
1120 | " major = %u;\n" | |
1121 | " minor = %u;\n" | |
30bdb6e4 | 1122 | " uuid = \"%s\";\n" |
d793d5e1 MD |
1123 | " byte_order = %s;\n" |
1124 | " packet.header := struct {\n" | |
1125 | " uint32_t magic;\n" | |
1ec3f75a | 1126 | " uint8_t uuid[16];\n" |
d793d5e1 | 1127 | " uint32_t stream_id;\n" |
0eb25f58 | 1128 | " };\n" |
d793d5e1 | 1129 | "};\n\n", |
a90917c3 MD |
1130 | lttng_alignof(uint8_t) * CHAR_BIT, |
1131 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1132 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1133 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
1134 | sizeof(unsigned long) * CHAR_BIT, |
1135 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
1136 | CTF_SPEC_MAJOR, |
1137 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
1138 | uuid_s, |
1139 | #ifdef __BIG_ENDIAN | |
1140 | "be" | |
1141 | #else | |
1142 | "le" | |
1143 | #endif | |
1144 | ); | |
1145 | if (ret) | |
1146 | goto end; | |
1147 | ||
99dc9597 MD |
1148 | ret = lttng_metadata_printf(session, |
1149 | "env {\n" | |
a6058143 | 1150 | " hostname = \"%s\";\n" |
c6c9e10f | 1151 | " domain = \"kernel\";\n" |
99dc9597 | 1152 | " sysname = \"%s\";\n" |
c6c9e10f MD |
1153 | " kernel_release = \"%s\";\n" |
1154 | " kernel_version = \"%s\";\n" | |
1155 | " tracer_name = \"lttng-modules\";\n" | |
1156 | " tracer_major = %d;\n" | |
1157 | " tracer_minor = %d;\n" | |
1158 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 1159 | "};\n\n", |
3d0d43db | 1160 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
1161 | utsname()->sysname, |
1162 | utsname()->release, | |
c6c9e10f MD |
1163 | utsname()->version, |
1164 | LTTNG_MODULES_MAJOR_VERSION, | |
1165 | LTTNG_MODULES_MINOR_VERSION, | |
1166 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
1167 | ); |
1168 | if (ret) | |
1169 | goto end; | |
1170 | ||
a3ccff4f MD |
1171 | ret = lttng_metadata_printf(session, |
1172 | "clock {\n" | |
a82c63f1 MD |
1173 | " name = %s;\n", |
1174 | "monotonic" | |
1175 | ); | |
1176 | if (ret) | |
1177 | goto end; | |
1178 | ||
1179 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1180 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1181 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1182 | clock_uuid_s |
1183 | ); | |
1184 | if (ret) | |
1185 | goto end; | |
1186 | } | |
1187 | ||
1188 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1189 | " description = \"Monotonic Clock\";\n" |
1190 | " freq = %llu; /* Frequency, in Hz */\n" | |
1191 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1192 | " offset = %llu;\n" | |
1193 | "};\n\n", | |
a3ccff4f MD |
1194 | (unsigned long long) trace_clock_freq(), |
1195 | (unsigned long long) measure_clock_offset() | |
1196 | ); | |
1197 | if (ret) | |
1198 | goto end; | |
1199 | ||
1200 | ret = lttng_metadata_printf(session, | |
1201 | "typealias integer {\n" | |
1202 | " size = 27; align = 1; signed = false;\n" | |
1203 | " map = clock.monotonic.value;\n" | |
1204 | "} := uint27_clock_monotonic_t;\n" | |
1205 | "\n" | |
1206 | "typealias integer {\n" | |
1207 | " size = 32; align = %u; signed = false;\n" | |
1208 | " map = clock.monotonic.value;\n" | |
1209 | "} := uint32_clock_monotonic_t;\n" | |
1210 | "\n" | |
1211 | "typealias integer {\n" | |
1212 | " size = 64; align = %u; signed = false;\n" | |
1213 | " map = clock.monotonic.value;\n" | |
1214 | "} := uint64_clock_monotonic_t;\n\n", | |
1215 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1216 | lttng_alignof(uint64_t) * CHAR_BIT | |
1217 | ); | |
1218 | if (ret) | |
1219 | goto end; | |
1220 | ||
a90917c3 | 1221 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1222 | if (ret) |
1223 | goto end; | |
1224 | ||
a90917c3 | 1225 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1226 | if (ret) |
1227 | goto end; | |
1228 | ||
c099397a MD |
1229 | skip_session: |
1230 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1231 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1232 | if (ret) |
1233 | goto end; | |
1234 | } | |
1235 | ||
1236 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1237 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1238 | if (ret) |
1239 | goto end; | |
1240 | } | |
1241 | session->metadata_dumped = 1; | |
1242 | end: | |
1243 | return ret; | |
1244 | } | |
1245 | ||
c0e31d2e | 1246 | /** |
a90917c3 | 1247 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1248 | * @transport: transport structure |
1249 | * | |
1250 | * Registers a transport which can be used as output to extract the data out of | |
1251 | * LTTng. The module calling this registration function must ensure that no | |
1252 | * trap-inducing code will be executed by the transport functions. E.g. | |
1253 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1254 | * is made visible to the transport function. This registration acts as a | |
1255 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1256 | * after its registration must it synchronize the TLBs. | |
1257 | */ | |
a90917c3 | 1258 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1259 | { |
1260 | /* | |
1261 | * Make sure no page fault can be triggered by the module about to be | |
1262 | * registered. We deal with this here so we don't have to call | |
1263 | * vmalloc_sync_all() in each module's init. | |
1264 | */ | |
6d2a620c | 1265 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1266 | |
1267 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1268 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1269 | mutex_unlock(&sessions_mutex); |
1270 | } | |
a90917c3 | 1271 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1272 | |
1273 | /** | |
a90917c3 | 1274 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1275 | * @transport: transport structure |
1276 | */ | |
a90917c3 | 1277 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1278 | { |
1279 | mutex_lock(&sessions_mutex); | |
1280 | list_del(&transport->node); | |
1281 | mutex_unlock(&sessions_mutex); | |
1282 | } | |
a90917c3 | 1283 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 1284 | |
a90917c3 | 1285 | static int __init lttng_events_init(void) |
4e3c1b9b | 1286 | { |
1c25284c MD |
1287 | int ret; |
1288 | ||
91c2dd86 JD |
1289 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
1290 | if (ret) | |
1291 | return ret; | |
66861b2e MD |
1292 | ret = wrapper_get_pfnblock_flags_mask_init(); |
1293 | if (ret) | |
1294 | return ret; | |
20591cf7 MD |
1295 | ret = lttng_tracepoint_init(); |
1296 | if (ret) | |
1297 | return ret; | |
a90917c3 | 1298 | event_cache = KMEM_CACHE(lttng_event, 0); |
20591cf7 MD |
1299 | if (!event_cache) { |
1300 | ret = -ENOMEM; | |
1301 | goto error_kmem; | |
1302 | } | |
80996790 | 1303 | ret = lttng_abi_init(); |
02119ee5 MD |
1304 | if (ret) |
1305 | goto error_abi; | |
0c956676 MD |
1306 | ret = lttng_logger_init(); |
1307 | if (ret) | |
1308 | goto error_logger; | |
4e3c1b9b | 1309 | return 0; |
0c956676 MD |
1310 | |
1311 | error_logger: | |
1312 | lttng_abi_exit(); | |
02119ee5 | 1313 | error_abi: |
1c25284c | 1314 | kmem_cache_destroy(event_cache); |
20591cf7 MD |
1315 | error_kmem: |
1316 | lttng_tracepoint_exit(); | |
1c25284c | 1317 | return ret; |
4e3c1b9b MD |
1318 | } |
1319 | ||
a90917c3 | 1320 | module_init(lttng_events_init); |
11b5a3c2 | 1321 | |
a90917c3 | 1322 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 1323 | { |
a90917c3 | 1324 | struct lttng_session *session, *tmpsession; |
92e94819 | 1325 | |
0c956676 | 1326 | lttng_logger_exit(); |
80996790 | 1327 | lttng_abi_exit(); |
92e94819 | 1328 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 1329 | lttng_session_destroy(session); |
11b5a3c2 | 1330 | kmem_cache_destroy(event_cache); |
20591cf7 | 1331 | lttng_tracepoint_exit(); |
4e3c1b9b | 1332 | } |
92e94819 | 1333 | |
a90917c3 | 1334 | module_exit(lttng_events_exit); |
11b5a3c2 | 1335 | |
92e94819 MD |
1336 | MODULE_LICENSE("GPL and additional rights"); |
1337 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
1338 | MODULE_DESCRIPTION("LTTng Events"); | |
9a9973ef MD |
1339 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
1340 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
309370e2 MD |
1341 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
1342 | LTTNG_MODULES_EXTRAVERSION); |