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