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 | ||
165eee70 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> |
a864fb02 | 37 | #include "wrapper/uuid.h" |
b13f3ebe | 38 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
a82c63f1 | 39 | #include "wrapper/random.h" |
3a523f5b | 40 | #include "wrapper/tracepoint.h" |
b8590f40 | 41 | #include "lttng-kernel-version.h" |
a90917c3 MD |
42 | #include "lttng-events.h" |
43 | #include "lttng-tracer.h" | |
6dccd6c1 | 44 | #include "lttng-abi-old.h" |
4e3c1b9b | 45 | |
d83004aa JD |
46 | #define METADATA_CACHE_DEFAULT_SIZE 4096 |
47 | ||
4e3c1b9b | 48 | static LIST_HEAD(sessions); |
a90917c3 | 49 | static LIST_HEAD(lttng_transport_list); |
d83004aa JD |
50 | /* |
51 | * Protect the sessions and metadata caches. | |
52 | */ | |
4e3c1b9b MD |
53 | static DEFINE_MUTEX(sessions_mutex); |
54 | static struct kmem_cache *event_cache; | |
55 | ||
a90917c3 MD |
56 | static void _lttng_event_destroy(struct lttng_event *event); |
57 | static void _lttng_channel_destroy(struct lttng_channel *chan); | |
58 | static int _lttng_event_unregister(struct lttng_event *event); | |
c099397a | 59 | static |
a90917c3 MD |
60 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
61 | struct lttng_channel *chan, | |
62 | struct lttng_event *event); | |
c099397a | 63 | static |
a90917c3 | 64 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
d83004aa JD |
65 | static |
66 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream); | |
c099397a | 67 | |
c099397a | 68 | void synchronize_trace(void) |
abcca994 MD |
69 | { |
70 | synchronize_sched(); | |
b8590f40 MD |
71 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
72 | #ifdef CONFIG_PREEMPT_RT_FULL | |
73 | synchronize_rcu(); | |
74 | #endif | |
75 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ | |
abcca994 MD |
76 | #ifdef CONFIG_PREEMPT_RT |
77 | synchronize_rcu(); | |
78 | #endif | |
b8590f40 | 79 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
abcca994 MD |
80 | } |
81 | ||
a90917c3 | 82 | struct lttng_session *lttng_session_create(void) |
4e3c1b9b | 83 | { |
a90917c3 | 84 | struct lttng_session *session; |
d83004aa | 85 | struct lttng_metadata_cache *metadata_cache; |
4e3c1b9b MD |
86 | |
87 | mutex_lock(&sessions_mutex); | |
a90917c3 | 88 | session = kzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
4e3c1b9b | 89 | if (!session) |
d83004aa | 90 | goto err; |
4e3c1b9b | 91 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 92 | INIT_LIST_HEAD(&session->events); |
d793d5e1 | 93 | uuid_le_gen(&session->uuid); |
d83004aa JD |
94 | |
95 | metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache), | |
96 | GFP_KERNEL); | |
97 | if (!metadata_cache) | |
98 | goto err_free_session; | |
99 | metadata_cache->data = kzalloc(METADATA_CACHE_DEFAULT_SIZE, | |
100 | GFP_KERNEL); | |
101 | if (!metadata_cache->data) | |
102 | goto err_free_cache; | |
103 | metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE; | |
104 | kref_init(&metadata_cache->refcount); | |
9a0aa3b1 | 105 | mutex_init(&metadata_cache->lock); |
d83004aa JD |
106 | session->metadata_cache = metadata_cache; |
107 | INIT_LIST_HEAD(&metadata_cache->metadata_stream); | |
a36580d5 MD |
108 | memcpy(&metadata_cache->uuid, &session->uuid, |
109 | sizeof(metadata_cache->uuid)); | |
4e3c1b9b MD |
110 | list_add(&session->list, &sessions); |
111 | mutex_unlock(&sessions_mutex); | |
112 | return session; | |
d83004aa JD |
113 | |
114 | err_free_cache: | |
115 | kfree(metadata_cache); | |
116 | err_free_session: | |
117 | kfree(session); | |
118 | err: | |
119 | mutex_unlock(&sessions_mutex); | |
120 | return NULL; | |
121 | } | |
122 | ||
123 | void metadata_cache_destroy(struct kref *kref) | |
124 | { | |
125 | struct lttng_metadata_cache *cache = | |
126 | container_of(kref, struct lttng_metadata_cache, refcount); | |
127 | kfree(cache->data); | |
128 | kfree(cache); | |
4e3c1b9b MD |
129 | } |
130 | ||
a90917c3 | 131 | void lttng_session_destroy(struct lttng_session *session) |
4e3c1b9b | 132 | { |
a90917c3 MD |
133 | struct lttng_channel *chan, *tmpchan; |
134 | struct lttng_event *event, *tmpevent; | |
d83004aa | 135 | struct lttng_metadata_stream *metadata_stream; |
dda6a249 | 136 | int ret; |
4e3c1b9b MD |
137 | |
138 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 139 | ACCESS_ONCE(session->active) = 0; |
1ec65de1 MD |
140 | list_for_each_entry(chan, &session->chan, list) { |
141 | ret = lttng_syscalls_unregister(chan); | |
142 | WARN_ON(ret); | |
143 | } | |
dda6a249 | 144 | list_for_each_entry(event, &session->events, list) { |
a90917c3 | 145 | ret = _lttng_event_unregister(event); |
dda6a249 MD |
146 | WARN_ON(ret); |
147 | } | |
abcca994 | 148 | synchronize_trace(); /* Wait for in-flight events to complete */ |
4e3c1b9b | 149 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
a90917c3 | 150 | _lttng_event_destroy(event); |
d83004aa JD |
151 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { |
152 | BUG_ON(chan->channel_type == METADATA_CHANNEL); | |
a90917c3 | 153 | _lttng_channel_destroy(chan); |
d83004aa JD |
154 | } |
155 | list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) | |
156 | _lttng_metadata_channel_hangup(metadata_stream); | |
157 | kref_put(&session->metadata_cache->refcount, metadata_cache_destroy); | |
4e3c1b9b MD |
158 | list_del(&session->list); |
159 | mutex_unlock(&sessions_mutex); | |
160 | kfree(session); | |
161 | } | |
162 | ||
a90917c3 | 163 | int lttng_session_enable(struct lttng_session *session) |
c0e31d2e MD |
164 | { |
165 | int ret = 0; | |
a90917c3 | 166 | struct lttng_channel *chan; |
c0e31d2e MD |
167 | |
168 | mutex_lock(&sessions_mutex); | |
169 | if (session->active) { | |
170 | ret = -EBUSY; | |
171 | goto end; | |
172 | } | |
c099397a MD |
173 | |
174 | /* | |
175 | * Snapshot the number of events per channel to know the type of header | |
176 | * we need to use. | |
177 | */ | |
178 | list_for_each_entry(chan, &session->chan, list) { | |
179 | if (chan->header_type) | |
180 | continue; /* don't change it if session stop/restart */ | |
181 | if (chan->free_event_id < 31) | |
182 | chan->header_type = 1; /* compact */ | |
183 | else | |
184 | chan->header_type = 2; /* large */ | |
185 | } | |
186 | ||
52fc2e1f | 187 | ACCESS_ONCE(session->active) = 1; |
8070f5c0 | 188 | ACCESS_ONCE(session->been_active) = 1; |
a90917c3 | 189 | ret = _lttng_session_metadata_statedump(session); |
c337ddc2 MD |
190 | if (ret) { |
191 | ACCESS_ONCE(session->active) = 0; | |
192 | goto end; | |
193 | } | |
194 | ret = lttng_statedump_start(session); | |
360f38ea | 195 | if (ret) |
c099397a | 196 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
197 | end: |
198 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 199 | return ret; |
c0e31d2e MD |
200 | } |
201 | ||
a90917c3 | 202 | int lttng_session_disable(struct lttng_session *session) |
c0e31d2e MD |
203 | { |
204 | int ret = 0; | |
205 | ||
206 | mutex_lock(&sessions_mutex); | |
207 | if (!session->active) { | |
208 | ret = -EBUSY; | |
209 | goto end; | |
210 | } | |
52fc2e1f | 211 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
212 | end: |
213 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 214 | return ret; |
c0e31d2e MD |
215 | } |
216 | ||
a90917c3 | 217 | int lttng_channel_enable(struct lttng_channel *channel) |
e64957da MD |
218 | { |
219 | int old; | |
220 | ||
d83004aa | 221 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 222 | return -EPERM; |
e64957da MD |
223 | old = xchg(&channel->enabled, 1); |
224 | if (old) | |
225 | return -EEXIST; | |
226 | return 0; | |
227 | } | |
228 | ||
a90917c3 | 229 | int lttng_channel_disable(struct lttng_channel *channel) |
e64957da MD |
230 | { |
231 | int old; | |
232 | ||
d83004aa | 233 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 234 | return -EPERM; |
e64957da MD |
235 | old = xchg(&channel->enabled, 0); |
236 | if (!old) | |
237 | return -EEXIST; | |
238 | return 0; | |
239 | } | |
240 | ||
a90917c3 | 241 | int lttng_event_enable(struct lttng_event *event) |
e64957da MD |
242 | { |
243 | int old; | |
244 | ||
d83004aa | 245 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 246 | return -EPERM; |
e64957da MD |
247 | old = xchg(&event->enabled, 1); |
248 | if (old) | |
249 | return -EEXIST; | |
250 | return 0; | |
251 | } | |
252 | ||
a90917c3 | 253 | int lttng_event_disable(struct lttng_event *event) |
e64957da MD |
254 | { |
255 | int old; | |
256 | ||
d83004aa | 257 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 258 | return -EPERM; |
e64957da MD |
259 | old = xchg(&event->enabled, 0); |
260 | if (!old) | |
261 | return -EEXIST; | |
262 | return 0; | |
263 | } | |
264 | ||
a90917c3 | 265 | static struct lttng_transport *lttng_transport_find(const char *name) |
f3d01b96 | 266 | { |
a90917c3 | 267 | struct lttng_transport *transport; |
f3d01b96 | 268 | |
a90917c3 | 269 | list_for_each_entry(transport, <tng_transport_list, node) { |
f3d01b96 MD |
270 | if (!strcmp(transport->name, name)) |
271 | return transport; | |
272 | } | |
273 | return NULL; | |
274 | } | |
275 | ||
a90917c3 | 276 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
5dbbdb43 MD |
277 | const char *transport_name, |
278 | void *buf_addr, | |
4e3c1b9b MD |
279 | size_t subbuf_size, size_t num_subbuf, |
280 | unsigned int switch_timer_interval, | |
d83004aa JD |
281 | unsigned int read_timer_interval, |
282 | enum channel_type channel_type) | |
4e3c1b9b | 283 | { |
a90917c3 MD |
284 | struct lttng_channel *chan; |
285 | struct lttng_transport *transport = NULL; | |
4e3c1b9b MD |
286 | |
287 | mutex_lock(&sessions_mutex); | |
d83004aa | 288 | if (session->been_active && channel_type != METADATA_CHANNEL) |
e5382b6d | 289 | goto active; /* Refuse to add channel to active session */ |
a90917c3 | 290 | transport = lttng_transport_find(transport_name); |
f3d01b96 MD |
291 | if (!transport) { |
292 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
293 | transport_name); | |
c0e31d2e | 294 | goto notransport; |
f3d01b96 | 295 | } |
a33c9927 MD |
296 | if (!try_module_get(transport->owner)) { |
297 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
298 | goto notransport; | |
299 | } | |
a90917c3 | 300 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
4e3c1b9b | 301 | if (!chan) |
c0e31d2e | 302 | goto nomem; |
4e3c1b9b | 303 | chan->session = session; |
05d32c64 | 304 | chan->id = session->free_chan_id++; |
3b731ab1 | 305 | chan->ops = &transport->ops; |
125b4df4 MD |
306 | /* |
307 | * Note: the channel creation op already writes into the packet | |
308 | * headers. Therefore the "chan" information used as input | |
309 | * should be already accessible. | |
310 | */ | |
5f5ddf01 MD |
311 | chan->chan = transport->ops.channel_create(transport_name, |
312 | chan, buf_addr, subbuf_size, num_subbuf, | |
313 | switch_timer_interval, read_timer_interval); | |
f3d01b96 MD |
314 | if (!chan->chan) |
315 | goto create_error; | |
e64957da | 316 | chan->enabled = 1; |
a33c9927 | 317 | chan->transport = transport; |
d83004aa | 318 | chan->channel_type = channel_type; |
4e3c1b9b MD |
319 | list_add(&chan->list, &session->chan); |
320 | mutex_unlock(&sessions_mutex); | |
321 | return chan; | |
322 | ||
f3d01b96 MD |
323 | create_error: |
324 | kfree(chan); | |
c0e31d2e | 325 | nomem: |
a33c9927 MD |
326 | if (transport) |
327 | module_put(transport->owner); | |
c0e31d2e | 328 | notransport: |
e5382b6d | 329 | active: |
4e3c1b9b MD |
330 | mutex_unlock(&sessions_mutex); |
331 | return NULL; | |
332 | } | |
333 | ||
334 | /* | |
d83004aa JD |
335 | * Only used internally at session destruction for per-cpu channels, and |
336 | * when metadata channel is released. | |
337 | * Needs to be called with sessions mutex held. | |
4e3c1b9b | 338 | */ |
aa7c23a9 | 339 | static |
a90917c3 | 340 | void _lttng_channel_destroy(struct lttng_channel *chan) |
4e3c1b9b | 341 | { |
11b5a3c2 | 342 | chan->ops->channel_destroy(chan->chan); |
a33c9927 | 343 | module_put(chan->transport->owner); |
4e3c1b9b | 344 | list_del(&chan->list); |
8070f5c0 | 345 | lttng_destroy_context(chan->ctx); |
4e3c1b9b MD |
346 | kfree(chan); |
347 | } | |
348 | ||
d83004aa JD |
349 | void lttng_metadata_channel_destroy(struct lttng_channel *chan) |
350 | { | |
351 | BUG_ON(chan->channel_type != METADATA_CHANNEL); | |
352 | ||
353 | /* Protect the metadata cache with the sessions_mutex. */ | |
354 | mutex_lock(&sessions_mutex); | |
355 | _lttng_channel_destroy(chan); | |
356 | mutex_unlock(&sessions_mutex); | |
357 | } | |
358 | EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy); | |
359 | ||
360 | static | |
361 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream) | |
362 | { | |
363 | stream->finalized = 1; | |
364 | wake_up_interruptible(&stream->read_wait); | |
365 | } | |
366 | ||
e5382b6d MD |
367 | /* |
368 | * Supports event creation while tracing session is active. | |
369 | */ | |
a90917c3 | 370 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
d6d808f3 | 371 | struct lttng_kernel_event *event_param, |
259b6cb3 MD |
372 | void *filter, |
373 | const struct lttng_event_desc *internal_desc) | |
4e3c1b9b | 374 | { |
a90917c3 | 375 | struct lttng_event *event; |
3d084699 | 376 | int ret; |
4e3c1b9b MD |
377 | |
378 | mutex_lock(&sessions_mutex); | |
abc0446a | 379 | if (chan->free_event_id == -1U) { |
4cf0bf51 | 380 | ret = -EMFILE; |
e5382b6d | 381 | goto full; |
abc0446a | 382 | } |
4e3c1b9b | 383 | /* |
dda6a249 MD |
384 | * This is O(n^2) (for each event, the loop is called at event |
385 | * creation). Might require a hash if we have lots of events. | |
4e3c1b9b | 386 | */ |
abc0446a MD |
387 | list_for_each_entry(event, &chan->session->events, list) { |
388 | if (!strcmp(event->desc->name, event_param->name)) { | |
f046a95d MD |
389 | /* |
390 | * Allow events with the same name to appear in | |
391 | * different channels. | |
392 | */ | |
393 | if (event->chan == chan) { | |
394 | ret = -EEXIST; | |
395 | goto exist; | |
396 | } | |
abc0446a MD |
397 | } |
398 | } | |
11b5a3c2 | 399 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
abc0446a | 400 | if (!event) { |
4cf0bf51 | 401 | ret = -ENOMEM; |
4e3c1b9b | 402 | goto cache_error; |
abc0446a | 403 | } |
4e3c1b9b MD |
404 | event->chan = chan; |
405 | event->filter = filter; | |
e5382b6d | 406 | event->id = chan->free_event_id++; |
e64957da | 407 | event->enabled = 1; |
d6d808f3 | 408 | event->instrumentation = event_param->instrumentation; |
a90917c3 | 409 | /* Populate lttng_event structure before tracepoint registration. */ |
e5382b6d | 410 | smp_wmb(); |
d6d808f3 | 411 | switch (event_param->instrumentation) { |
ab2277d6 | 412 | case LTTNG_KERNEL_TRACEPOINT: |
a90917c3 | 413 | event->desc = lttng_event_get(event_param->name); |
abc0446a | 414 | if (!event->desc) { |
4cf0bf51 | 415 | ret = -ENOENT; |
d3dbe23c | 416 | goto register_error; |
abc0446a | 417 | } |
20591cf7 | 418 | ret = lttng_wrapper_tracepoint_probe_register(event->desc->kname, |
d3dbe23c MD |
419 | event->desc->probe_callback, |
420 | event); | |
abc0446a | 421 | if (ret) { |
4cf0bf51 | 422 | ret = -EINVAL; |
11b5a3c2 | 423 | goto register_error; |
abc0446a | 424 | } |
baf20995 | 425 | break; |
ab2277d6 | 426 | case LTTNG_KERNEL_KPROBE: |
30bdb6e4 | 427 | ret = lttng_kprobes_register(event_param->name, |
f17701fb MD |
428 | event_param->u.kprobe.symbol_name, |
429 | event_param->u.kprobe.offset, | |
430 | event_param->u.kprobe.addr, | |
431 | event); | |
abc0446a | 432 | if (ret) { |
4cf0bf51 | 433 | ret = -EINVAL; |
d6d808f3 | 434 | goto register_error; |
abc0446a | 435 | } |
edeb3137 MD |
436 | ret = try_module_get(event->desc->owner); |
437 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 438 | break; |
7371f44c MD |
439 | case LTTNG_KERNEL_KRETPROBE: |
440 | { | |
a90917c3 | 441 | struct lttng_event *event_return; |
7371f44c MD |
442 | |
443 | /* kretprobe defines 2 events */ | |
444 | event_return = | |
445 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
abc0446a | 446 | if (!event_return) { |
4cf0bf51 | 447 | ret = -ENOMEM; |
7371f44c | 448 | goto register_error; |
abc0446a | 449 | } |
7371f44c MD |
450 | event_return->chan = chan; |
451 | event_return->filter = filter; | |
452 | event_return->id = chan->free_event_id++; | |
453 | event_return->enabled = 1; | |
454 | event_return->instrumentation = event_param->instrumentation; | |
455 | /* | |
a90917c3 | 456 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
457 | */ |
458 | smp_wmb(); | |
459 | ret = lttng_kretprobes_register(event_param->name, | |
460 | event_param->u.kretprobe.symbol_name, | |
461 | event_param->u.kretprobe.offset, | |
462 | event_param->u.kretprobe.addr, | |
463 | event, event_return); | |
464 | if (ret) { | |
465 | kmem_cache_free(event_cache, event_return); | |
4cf0bf51 | 466 | ret = -EINVAL; |
7371f44c MD |
467 | goto register_error; |
468 | } | |
469 | /* Take 2 refs on the module: one per event. */ | |
470 | ret = try_module_get(event->desc->owner); | |
471 | WARN_ON_ONCE(!ret); | |
472 | ret = try_module_get(event->desc->owner); | |
473 | WARN_ON_ONCE(!ret); | |
a90917c3 | 474 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c | 475 | event_return); |
abc0446a | 476 | WARN_ON_ONCE(ret > 0); |
7371f44c MD |
477 | if (ret) { |
478 | kmem_cache_free(event_cache, event_return); | |
479 | module_put(event->desc->owner); | |
480 | module_put(event->desc->owner); | |
481 | goto statedump_error; | |
482 | } | |
483 | list_add(&event_return->list, &chan->session->events); | |
484 | break; | |
485 | } | |
ab2277d6 | 486 | case LTTNG_KERNEL_FUNCTION: |
30bdb6e4 | 487 | ret = lttng_ftrace_register(event_param->name, |
e0a7a7c4 MD |
488 | event_param->u.ftrace.symbol_name, |
489 | event); | |
abc0446a | 490 | if (ret) { |
e0a7a7c4 | 491 | goto register_error; |
abc0446a | 492 | } |
edeb3137 MD |
493 | ret = try_module_get(event->desc->owner); |
494 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 495 | break; |
1ec65de1 | 496 | case LTTNG_KERNEL_NOOP: |
259b6cb3 | 497 | event->desc = internal_desc; |
abc0446a | 498 | if (!event->desc) { |
4cf0bf51 | 499 | ret = -EINVAL; |
259b6cb3 | 500 | goto register_error; |
abc0446a | 501 | } |
1ec65de1 | 502 | break; |
baf20995 MD |
503 | default: |
504 | WARN_ON_ONCE(1); | |
4cf0bf51 | 505 | ret = -EINVAL; |
df07930b | 506 | goto register_error; |
baf20995 | 507 | } |
a90917c3 | 508 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
abc0446a MD |
509 | WARN_ON_ONCE(ret > 0); |
510 | if (ret) { | |
c099397a | 511 | goto statedump_error; |
abc0446a | 512 | } |
dda6a249 | 513 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 514 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
515 | return event; |
516 | ||
c099397a | 517 | statedump_error: |
259b6cb3 | 518 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 519 | register_error: |
11b5a3c2 | 520 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
521 | cache_error: |
522 | exist: | |
e5382b6d | 523 | full: |
4e3c1b9b | 524 | mutex_unlock(&sessions_mutex); |
4cf0bf51 | 525 | return ERR_PTR(ret); |
4e3c1b9b MD |
526 | } |
527 | ||
528 | /* | |
529 | * Only used internally at session destruction. | |
530 | */ | |
a90917c3 | 531 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 532 | { |
11b5a3c2 MD |
533 | int ret = -EINVAL; |
534 | ||
38d024ae | 535 | switch (event->instrumentation) { |
ab2277d6 | 536 | case LTTNG_KERNEL_TRACEPOINT: |
20591cf7 | 537 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
85a9ca7f | 538 | event->desc->probe_callback, |
11b5a3c2 MD |
539 | event); |
540 | if (ret) | |
541 | return ret; | |
baf20995 | 542 | break; |
ab2277d6 | 543 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 544 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
545 | ret = 0; |
546 | break; | |
7371f44c MD |
547 | case LTTNG_KERNEL_KRETPROBE: |
548 | lttng_kretprobes_unregister(event); | |
549 | ret = 0; | |
550 | break; | |
ab2277d6 | 551 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
552 | lttng_ftrace_unregister(event); |
553 | ret = 0; | |
554 | break; | |
259b6cb3 MD |
555 | case LTTNG_KERNEL_NOOP: |
556 | ret = 0; | |
557 | break; | |
baf20995 MD |
558 | default: |
559 | WARN_ON_ONCE(1); | |
560 | } | |
dda6a249 MD |
561 | return ret; |
562 | } | |
563 | ||
564 | /* | |
565 | * Only used internally at session destruction. | |
566 | */ | |
be066e6c | 567 | static |
a90917c3 | 568 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 569 | { |
edeb3137 MD |
570 | switch (event->instrumentation) { |
571 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 572 | lttng_event_put(event->desc); |
edeb3137 MD |
573 | break; |
574 | case LTTNG_KERNEL_KPROBE: | |
575 | module_put(event->desc->owner); | |
576 | lttng_kprobes_destroy_private(event); | |
577 | break; | |
7371f44c MD |
578 | case LTTNG_KERNEL_KRETPROBE: |
579 | module_put(event->desc->owner); | |
580 | lttng_kretprobes_destroy_private(event); | |
581 | break; | |
edeb3137 MD |
582 | case LTTNG_KERNEL_FUNCTION: |
583 | module_put(event->desc->owner); | |
584 | lttng_ftrace_destroy_private(event); | |
585 | break; | |
259b6cb3 MD |
586 | case LTTNG_KERNEL_NOOP: |
587 | break; | |
edeb3137 MD |
588 | default: |
589 | WARN_ON_ONCE(1); | |
590 | } | |
dda6a249 | 591 | list_del(&event->list); |
8070f5c0 | 592 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 593 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
594 | } |
595 | ||
1ec3f75a | 596 | /* |
d83004aa JD |
597 | * Serialize at most one packet worth of metadata into a metadata |
598 | * channel. | |
9a0aa3b1 MD |
599 | * We grab the metadata cache mutex to get exclusive access to our metadata |
600 | * buffer and to the metadata cache. Exclusive access to the metadata buffer | |
601 | * allows us to do racy operations such as looking for remaining space left in | |
602 | * packet and write, since mutual exclusion protects us from concurrent writes. | |
603 | * Mutual exclusion on the metadata cache allow us to read the cache content | |
604 | * without racing against reallocation of the cache by updates. | |
35097f36 JD |
605 | * Returns the number of bytes written in the channel, 0 if no data |
606 | * was written and a negative value on error. | |
1ec3f75a | 607 | */ |
b3b8072b MD |
608 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
609 | struct channel *chan) | |
d83004aa JD |
610 | { |
611 | struct lib_ring_buffer_ctx ctx; | |
612 | int ret = 0; | |
613 | size_t len, reserve_len; | |
614 | ||
f613e3e6 | 615 | /* |
9a0aa3b1 MD |
616 | * Ensure we support mutiple get_next / put sequences followed by |
617 | * put_next. The metadata cache lock protects reading the metadata | |
618 | * cache. It can indeed be read concurrently by "get_next_subbuf" and | |
619 | * "flush" operations on the buffer invoked by different processes. | |
620 | * Moreover, since the metadata cache memory can be reallocated, we | |
621 | * need to have exclusive access against updates even though we only | |
622 | * read it. | |
f613e3e6 | 623 | */ |
9a0aa3b1 | 624 | mutex_lock(&stream->metadata_cache->lock); |
f613e3e6 MD |
625 | WARN_ON(stream->metadata_in < stream->metadata_out); |
626 | if (stream->metadata_in != stream->metadata_out) | |
de23d59d | 627 | goto end; |
f613e3e6 | 628 | |
d83004aa | 629 | len = stream->metadata_cache->metadata_written - |
f613e3e6 | 630 | stream->metadata_in; |
9de2c215 | 631 | if (!len) |
de23d59d | 632 | goto end; |
d83004aa | 633 | reserve_len = min_t(size_t, |
b3b8072b | 634 | stream->transport->ops.packet_avail_size(chan), |
d83004aa | 635 | len); |
b3b8072b | 636 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
d83004aa JD |
637 | sizeof(char), -1); |
638 | /* | |
639 | * If reservation failed, return an error to the caller. | |
640 | */ | |
b3b8072b | 641 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
d83004aa JD |
642 | if (ret != 0) { |
643 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); | |
644 | goto end; | |
645 | } | |
b3b8072b | 646 | stream->transport->ops.event_write(&ctx, |
f613e3e6 | 647 | stream->metadata_cache->data + stream->metadata_in, |
d83004aa | 648 | reserve_len); |
b3b8072b | 649 | stream->transport->ops.event_commit(&ctx); |
f613e3e6 | 650 | stream->metadata_in += reserve_len; |
d83004aa JD |
651 | ret = reserve_len; |
652 | ||
653 | end: | |
9a0aa3b1 | 654 | mutex_unlock(&stream->metadata_cache->lock); |
d83004aa JD |
655 | return ret; |
656 | } | |
657 | ||
658 | /* | |
659 | * Write the metadata to the metadata cache. | |
660 | * Must be called with sessions_mutex held. | |
9a0aa3b1 MD |
661 | * The metadata cache lock protects us from concurrent read access from |
662 | * thread outputting metadata content to ring buffer. | |
d83004aa | 663 | */ |
a90917c3 | 664 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
665 | const char *fmt, ...) |
666 | { | |
c099397a | 667 | char *str; |
d83004aa | 668 | size_t len; |
c099397a | 669 | va_list ap; |
d83004aa | 670 | struct lttng_metadata_stream *stream; |
c099397a MD |
671 | |
672 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
673 | ||
674 | va_start(ap, fmt); | |
675 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
676 | va_end(ap); | |
677 | if (!str) | |
678 | return -ENOMEM; | |
679 | ||
1ec3f75a | 680 | len = strlen(str); |
9a0aa3b1 | 681 | mutex_lock(&session->metadata_cache->lock); |
d83004aa JD |
682 | if (session->metadata_cache->metadata_written + len > |
683 | session->metadata_cache->cache_alloc) { | |
684 | char *tmp_cache_realloc; | |
685 | unsigned int tmp_cache_alloc_size; | |
686 | ||
687 | tmp_cache_alloc_size = max_t(unsigned int, | |
688 | session->metadata_cache->cache_alloc + len, | |
689 | session->metadata_cache->cache_alloc << 1); | |
690 | tmp_cache_realloc = krealloc(session->metadata_cache->data, | |
691 | tmp_cache_alloc_size, GFP_KERNEL); | |
692 | if (!tmp_cache_realloc) | |
693 | goto err; | |
694 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; | |
695 | session->metadata_cache->data = tmp_cache_realloc; | |
c099397a | 696 | } |
d83004aa JD |
697 | memcpy(session->metadata_cache->data + |
698 | session->metadata_cache->metadata_written, | |
699 | str, len); | |
700 | session->metadata_cache->metadata_written += len; | |
9a0aa3b1 | 701 | mutex_unlock(&session->metadata_cache->lock); |
c099397a | 702 | kfree(str); |
d83004aa JD |
703 | |
704 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) | |
705 | wake_up_interruptible(&stream->read_wait); | |
706 | ||
707 | return 0; | |
708 | ||
709 | err: | |
9a0aa3b1 | 710 | mutex_unlock(&session->metadata_cache->lock); |
d83004aa JD |
711 | kfree(str); |
712 | return -ENOMEM; | |
c099397a MD |
713 | } |
714 | ||
d83004aa JD |
715 | /* |
716 | * Must be called with sessions_mutex held. | |
717 | */ | |
c099397a | 718 | static |
a90917c3 | 719 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 720 | const struct lttng_event_field *field) |
c099397a | 721 | { |
c099397a | 722 | int ret = 0; |
c099397a | 723 | |
8070f5c0 MD |
724 | switch (field->type.atype) { |
725 | case atype_integer: | |
726 | ret = lttng_metadata_printf(session, | |
244465ab | 727 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
728 | field->type.u.basic.integer.size, |
729 | field->type.u.basic.integer.alignment, | |
730 | field->type.u.basic.integer.signedness, | |
731 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
732 | ? "none" | |
733 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
734 | ? "UTF8" | |
735 | : "ASCII", | |
736 | field->type.u.basic.integer.base, | |
c099397a | 737 | #ifdef __BIG_ENDIAN |
8070f5c0 | 738 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 739 | #else |
8070f5c0 | 740 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 741 | #endif |
8070f5c0 MD |
742 | field->name); |
743 | break; | |
744 | case atype_enum: | |
745 | ret = lttng_metadata_printf(session, | |
244465ab | 746 | " %s _%s;\n", |
8070f5c0 MD |
747 | field->type.u.basic.enumeration.name, |
748 | field->name); | |
749 | break; | |
750 | case atype_array: | |
751 | { | |
752 | const struct lttng_basic_type *elem_type; | |
753 | ||
754 | elem_type = &field->type.u.array.elem_type; | |
755 | ret = lttng_metadata_printf(session, | |
244465ab | 756 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
757 | elem_type->u.basic.integer.size, |
758 | elem_type->u.basic.integer.alignment, | |
759 | elem_type->u.basic.integer.signedness, | |
760 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
761 | ? "none" | |
762 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
763 | ? "UTF8" | |
764 | : "ASCII", | |
765 | elem_type->u.basic.integer.base, | |
8fa75f34 | 766 | #ifdef __BIG_ENDIAN |
8070f5c0 | 767 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 768 | #else |
8070f5c0 | 769 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 770 | #endif |
8070f5c0 MD |
771 | field->name, field->type.u.array.length); |
772 | break; | |
773 | } | |
774 | case atype_sequence: | |
775 | { | |
776 | const struct lttng_basic_type *elem_type; | |
777 | const struct lttng_basic_type *length_type; | |
778 | ||
779 | elem_type = &field->type.u.sequence.elem_type; | |
780 | length_type = &field->type.u.sequence.length_type; | |
781 | ret = lttng_metadata_printf(session, | |
782 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 783 | length_type->u.basic.integer.size, |
32257272 | 784 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
785 | length_type->u.basic.integer.signedness, |
786 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
787 | ? "none" | |
0635cdd4 | 788 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 789 | ? "UTF8" |
0635cdd4 | 790 | : "ASCII"), |
8070f5c0 | 791 | length_type->u.basic.integer.base, |
e0a7a7c4 | 792 | #ifdef __BIG_ENDIAN |
8070f5c0 | 793 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 794 | #else |
0635cdd4 | 795 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 796 | #endif |
27d2368e MD |
797 | field->name); |
798 | if (ret) | |
799 | return ret; | |
800 | ||
801 | ret = lttng_metadata_printf(session, | |
244465ab | 802 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 803 | elem_type->u.basic.integer.size, |
32257272 | 804 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
805 | elem_type->u.basic.integer.signedness, |
806 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
807 | ? "none" | |
0635cdd4 | 808 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 809 | ? "UTF8" |
0635cdd4 | 810 | : "ASCII"), |
8070f5c0 | 811 | elem_type->u.basic.integer.base, |
8fa75f34 | 812 | #ifdef __BIG_ENDIAN |
8070f5c0 | 813 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 814 | #else |
8070f5c0 | 815 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 816 | #endif |
8070f5c0 | 817 | field->name, |
27d2368e | 818 | field->name); |
8070f5c0 MD |
819 | break; |
820 | } | |
c099397a | 821 | |
8070f5c0 MD |
822 | case atype_string: |
823 | /* Default encoding is UTF8 */ | |
824 | ret = lttng_metadata_printf(session, | |
244465ab | 825 | " string%s _%s;\n", |
8070f5c0 MD |
826 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
827 | " { encoding = ASCII; }" : "", | |
828 | field->name); | |
829 | break; | |
830 | default: | |
831 | WARN_ON_ONCE(1); | |
832 | return -EINVAL; | |
833 | } | |
834 | return ret; | |
835 | } | |
836 | ||
837 | static | |
a90917c3 | 838 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
839 | struct lttng_ctx *ctx) |
840 | { | |
841 | int ret = 0; | |
842 | int i; | |
843 | ||
844 | if (!ctx) | |
845 | return 0; | |
846 | for (i = 0; i < ctx->nr_fields; i++) { | |
847 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
848 | ||
a90917c3 | 849 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
850 | if (ret) |
851 | return ret; | |
852 | } | |
853 | return ret; | |
854 | } | |
855 | ||
856 | static | |
a90917c3 MD |
857 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
858 | struct lttng_event *event) | |
8070f5c0 MD |
859 | { |
860 | const struct lttng_event_desc *desc = event->desc; | |
861 | int ret = 0; | |
862 | int i; | |
863 | ||
864 | for (i = 0; i < desc->nr_fields; i++) { | |
865 | const struct lttng_event_field *field = &desc->fields[i]; | |
866 | ||
a90917c3 | 867 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
868 | if (ret) |
869 | return ret; | |
c099397a MD |
870 | } |
871 | return ret; | |
872 | } | |
873 | ||
d83004aa JD |
874 | /* |
875 | * Must be called with sessions_mutex held. | |
876 | */ | |
c099397a | 877 | static |
a90917c3 MD |
878 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
879 | struct lttng_channel *chan, | |
880 | struct lttng_event *event) | |
c099397a MD |
881 | { |
882 | int ret = 0; | |
883 | ||
884 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
885 | return 0; | |
d83004aa | 886 | if (chan->channel_type == METADATA_CHANNEL) |
c099397a MD |
887 | return 0; |
888 | ||
889 | ret = lttng_metadata_printf(session, | |
890 | "event {\n" | |
ae734547 | 891 | " name = \"%s\";\n" |
c099397a | 892 | " id = %u;\n" |
b9074a1b | 893 | " stream_id = %u;\n", |
c099397a MD |
894 | event->desc->name, |
895 | event->id, | |
896 | event->chan->id); | |
897 | if (ret) | |
898 | goto end; | |
899 | ||
b9074a1b MD |
900 | if (event->ctx) { |
901 | ret = lttng_metadata_printf(session, | |
902 | " context := struct {\n"); | |
903 | if (ret) | |
904 | goto end; | |
905 | } | |
a90917c3 | 906 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
907 | if (ret) |
908 | goto end; | |
b9074a1b MD |
909 | if (event->ctx) { |
910 | ret = lttng_metadata_printf(session, | |
911 | " };\n"); | |
912 | if (ret) | |
913 | goto end; | |
914 | } | |
8070f5c0 MD |
915 | |
916 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
917 | " fields := struct {\n" |
918 | ); | |
919 | if (ret) | |
920 | goto end; | |
921 | ||
a90917c3 | 922 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
923 | if (ret) |
924 | goto end; | |
925 | ||
926 | /* | |
927 | * LTTng space reservation can only reserve multiples of the | |
928 | * byte size. | |
929 | */ | |
930 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
931 | " };\n" |
932 | "};\n\n"); | |
c099397a MD |
933 | if (ret) |
934 | goto end; | |
935 | ||
c099397a MD |
936 | event->metadata_dumped = 1; |
937 | end: | |
938 | return ret; | |
939 | ||
940 | } | |
941 | ||
d83004aa JD |
942 | /* |
943 | * Must be called with sessions_mutex held. | |
944 | */ | |
c099397a | 945 | static |
a90917c3 MD |
946 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
947 | struct lttng_channel *chan) | |
c099397a MD |
948 | { |
949 | int ret = 0; | |
950 | ||
951 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
952 | return 0; | |
d83004aa JD |
953 | |
954 | if (chan->channel_type == METADATA_CHANNEL) | |
c099397a MD |
955 | return 0; |
956 | ||
957 | WARN_ON_ONCE(!chan->header_type); | |
958 | ret = lttng_metadata_printf(session, | |
959 | "stream {\n" | |
960 | " id = %u;\n" | |
9115fbdc | 961 | " event.header := %s;\n" |
b9074a1b | 962 | " packet.context := struct packet_context;\n", |
c099397a MD |
963 | chan->id, |
964 | chan->header_type == 1 ? "struct event_header_compact" : | |
965 | "struct event_header_large"); | |
966 | if (ret) | |
967 | goto end; | |
968 | ||
b9074a1b MD |
969 | if (chan->ctx) { |
970 | ret = lttng_metadata_printf(session, | |
971 | " event.context := struct {\n"); | |
972 | if (ret) | |
973 | goto end; | |
974 | } | |
a90917c3 | 975 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
976 | if (ret) |
977 | goto end; | |
b9074a1b MD |
978 | if (chan->ctx) { |
979 | ret = lttng_metadata_printf(session, | |
980 | " };\n"); | |
981 | if (ret) | |
982 | goto end; | |
983 | } | |
8070f5c0 MD |
984 | |
985 | ret = lttng_metadata_printf(session, | |
b9074a1b | 986 | "};\n\n"); |
8070f5c0 | 987 | |
c099397a MD |
988 | chan->metadata_dumped = 1; |
989 | end: | |
990 | return ret; | |
991 | } | |
992 | ||
d83004aa JD |
993 | /* |
994 | * Must be called with sessions_mutex held. | |
995 | */ | |
9115fbdc | 996 | static |
a90917c3 | 997 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
998 | { |
999 | return lttng_metadata_printf(session, | |
1000 | "struct packet_context {\n" | |
a3ccff4f MD |
1001 | " uint64_clock_monotonic_t timestamp_begin;\n" |
1002 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
1003 | " uint64_t content_size;\n" |
1004 | " uint64_t packet_size;\n" | |
a9afe705 | 1005 | " unsigned long events_discarded;\n" |
9115fbdc | 1006 | " uint32_t cpu_id;\n" |
c6dfdf6f | 1007 | "};\n\n" |
9115fbdc MD |
1008 | ); |
1009 | } | |
1010 | ||
1011 | /* | |
1012 | * Compact header: | |
1013 | * id: range: 0 - 30. | |
1014 | * id 31 is reserved to indicate an extended header. | |
1015 | * | |
1016 | * Large header: | |
1017 | * id: range: 0 - 65534. | |
1018 | * id 65535 is reserved to indicate an extended header. | |
d83004aa JD |
1019 | * |
1020 | * Must be called with sessions_mutex held. | |
9115fbdc MD |
1021 | */ |
1022 | static | |
a90917c3 | 1023 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
1024 | { |
1025 | return lttng_metadata_printf(session, | |
1026 | "struct event_header_compact {\n" | |
1027 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
1028 | " variant <id> {\n" | |
1029 | " struct {\n" | |
a3ccff4f | 1030 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1031 | " } compact;\n" |
1032 | " struct {\n" | |
1033 | " uint32_t id;\n" | |
a3ccff4f | 1034 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1035 | " } extended;\n" |
1036 | " } v;\n" | |
1037 | "} align(%u);\n" | |
1038 | "\n" | |
1039 | "struct event_header_large {\n" | |
1040 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
1041 | " variant <id> {\n" | |
1042 | " struct {\n" | |
a3ccff4f | 1043 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1044 | " } compact;\n" |
1045 | " struct {\n" | |
1046 | " uint32_t id;\n" | |
a3ccff4f | 1047 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1048 | " } extended;\n" |
1049 | " } v;\n" | |
1050 | "} align(%u);\n\n", | |
a90917c3 MD |
1051 | lttng_alignof(uint32_t) * CHAR_BIT, |
1052 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
1053 | ); |
1054 | } | |
1055 | ||
a3ccff4f MD |
1056 | /* |
1057 | * Approximation of NTP time of day to clock monotonic correlation, | |
1058 | * taken at start of trace. | |
1059 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
1060 | * in future versions. | |
1061 | */ | |
1062 | static | |
1063 | uint64_t measure_clock_offset(void) | |
1064 | { | |
1065 | uint64_t offset, monotonic[2], realtime; | |
1066 | struct timespec rts = { 0, 0 }; | |
1067 | unsigned long flags; | |
1068 | ||
1069 | /* Disable interrupts to increase correlation precision. */ | |
1070 | local_irq_save(flags); | |
1071 | monotonic[0] = trace_clock_read64(); | |
1072 | getnstimeofday(&rts); | |
1073 | monotonic[1] = trace_clock_read64(); | |
1074 | local_irq_restore(flags); | |
1075 | ||
1076 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 1077 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
1078 | realtime += rts.tv_nsec; |
1079 | offset = realtime - offset; | |
1080 | return offset; | |
1081 | } | |
1082 | ||
c099397a MD |
1083 | /* |
1084 | * Output metadata into this session's metadata buffers. | |
d83004aa | 1085 | * Must be called with sessions_mutex held. |
c099397a MD |
1086 | */ |
1087 | static | |
a90917c3 | 1088 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 1089 | { |
30bdb6e4 | 1090 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 1091 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
1092 | struct lttng_channel *chan; |
1093 | struct lttng_event *event; | |
c099397a MD |
1094 | int ret = 0; |
1095 | ||
1096 | if (!ACCESS_ONCE(session->active)) | |
1097 | return 0; | |
1098 | if (session->metadata_dumped) | |
1099 | goto skip_session; | |
c099397a | 1100 | |
d793d5e1 | 1101 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
1102 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
1103 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
1104 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
1105 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
1106 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
1107 | |
1108 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1109 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
1110 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
1111 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
1112 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 1113 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
1114 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
1115 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
1116 | "\n" |
1117 | "trace {\n" | |
1118 | " major = %u;\n" | |
1119 | " minor = %u;\n" | |
30bdb6e4 | 1120 | " uuid = \"%s\";\n" |
d793d5e1 MD |
1121 | " byte_order = %s;\n" |
1122 | " packet.header := struct {\n" | |
1123 | " uint32_t magic;\n" | |
1ec3f75a | 1124 | " uint8_t uuid[16];\n" |
d793d5e1 | 1125 | " uint32_t stream_id;\n" |
0eb25f58 | 1126 | " };\n" |
d793d5e1 | 1127 | "};\n\n", |
a90917c3 MD |
1128 | lttng_alignof(uint8_t) * CHAR_BIT, |
1129 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1130 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1131 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
1132 | sizeof(unsigned long) * CHAR_BIT, |
1133 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
1134 | CTF_SPEC_MAJOR, |
1135 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
1136 | uuid_s, |
1137 | #ifdef __BIG_ENDIAN | |
1138 | "be" | |
1139 | #else | |
1140 | "le" | |
1141 | #endif | |
1142 | ); | |
1143 | if (ret) | |
1144 | goto end; | |
1145 | ||
99dc9597 MD |
1146 | ret = lttng_metadata_printf(session, |
1147 | "env {\n" | |
a6058143 | 1148 | " hostname = \"%s\";\n" |
c6c9e10f | 1149 | " domain = \"kernel\";\n" |
99dc9597 | 1150 | " sysname = \"%s\";\n" |
c6c9e10f MD |
1151 | " kernel_release = \"%s\";\n" |
1152 | " kernel_version = \"%s\";\n" | |
1153 | " tracer_name = \"lttng-modules\";\n" | |
1154 | " tracer_major = %d;\n" | |
1155 | " tracer_minor = %d;\n" | |
1156 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 1157 | "};\n\n", |
3d0d43db | 1158 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
1159 | utsname()->sysname, |
1160 | utsname()->release, | |
c6c9e10f MD |
1161 | utsname()->version, |
1162 | LTTNG_MODULES_MAJOR_VERSION, | |
1163 | LTTNG_MODULES_MINOR_VERSION, | |
1164 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
1165 | ); |
1166 | if (ret) | |
1167 | goto end; | |
1168 | ||
a3ccff4f MD |
1169 | ret = lttng_metadata_printf(session, |
1170 | "clock {\n" | |
a82c63f1 MD |
1171 | " name = %s;\n", |
1172 | "monotonic" | |
1173 | ); | |
1174 | if (ret) | |
1175 | goto end; | |
1176 | ||
1177 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1178 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1179 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1180 | clock_uuid_s |
1181 | ); | |
1182 | if (ret) | |
1183 | goto end; | |
1184 | } | |
1185 | ||
1186 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1187 | " description = \"Monotonic Clock\";\n" |
1188 | " freq = %llu; /* Frequency, in Hz */\n" | |
1189 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1190 | " offset = %llu;\n" | |
1191 | "};\n\n", | |
a3ccff4f MD |
1192 | (unsigned long long) trace_clock_freq(), |
1193 | (unsigned long long) measure_clock_offset() | |
1194 | ); | |
1195 | if (ret) | |
1196 | goto end; | |
1197 | ||
1198 | ret = lttng_metadata_printf(session, | |
1199 | "typealias integer {\n" | |
1200 | " size = 27; align = 1; signed = false;\n" | |
1201 | " map = clock.monotonic.value;\n" | |
1202 | "} := uint27_clock_monotonic_t;\n" | |
1203 | "\n" | |
1204 | "typealias integer {\n" | |
1205 | " size = 32; align = %u; signed = false;\n" | |
1206 | " map = clock.monotonic.value;\n" | |
1207 | "} := uint32_clock_monotonic_t;\n" | |
1208 | "\n" | |
1209 | "typealias integer {\n" | |
1210 | " size = 64; align = %u; signed = false;\n" | |
1211 | " map = clock.monotonic.value;\n" | |
1212 | "} := uint64_clock_monotonic_t;\n\n", | |
1213 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1214 | lttng_alignof(uint64_t) * CHAR_BIT | |
1215 | ); | |
1216 | if (ret) | |
1217 | goto end; | |
1218 | ||
a90917c3 | 1219 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1220 | if (ret) |
1221 | goto end; | |
1222 | ||
a90917c3 | 1223 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1224 | if (ret) |
1225 | goto end; | |
1226 | ||
c099397a MD |
1227 | skip_session: |
1228 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1229 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1230 | if (ret) |
1231 | goto end; | |
1232 | } | |
1233 | ||
1234 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1235 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1236 | if (ret) |
1237 | goto end; | |
1238 | } | |
1239 | session->metadata_dumped = 1; | |
1240 | end: | |
1241 | return ret; | |
1242 | } | |
1243 | ||
c0e31d2e | 1244 | /** |
a90917c3 | 1245 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1246 | * @transport: transport structure |
1247 | * | |
1248 | * Registers a transport which can be used as output to extract the data out of | |
1249 | * LTTng. The module calling this registration function must ensure that no | |
1250 | * trap-inducing code will be executed by the transport functions. E.g. | |
1251 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1252 | * is made visible to the transport function. This registration acts as a | |
1253 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1254 | * after its registration must it synchronize the TLBs. | |
1255 | */ | |
a90917c3 | 1256 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1257 | { |
1258 | /* | |
1259 | * Make sure no page fault can be triggered by the module about to be | |
1260 | * registered. We deal with this here so we don't have to call | |
1261 | * vmalloc_sync_all() in each module's init. | |
1262 | */ | |
6d2a620c | 1263 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1264 | |
1265 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1266 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1267 | mutex_unlock(&sessions_mutex); |
1268 | } | |
a90917c3 | 1269 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1270 | |
1271 | /** | |
a90917c3 | 1272 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1273 | * @transport: transport structure |
1274 | */ | |
a90917c3 | 1275 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1276 | { |
1277 | mutex_lock(&sessions_mutex); | |
1278 | list_del(&transport->node); | |
1279 | mutex_unlock(&sessions_mutex); | |
1280 | } | |
a90917c3 | 1281 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 1282 | |
a90917c3 | 1283 | static int __init lttng_events_init(void) |
4e3c1b9b | 1284 | { |
1c25284c MD |
1285 | int ret; |
1286 | ||
453b2495 JD |
1287 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
1288 | if (ret) | |
1289 | return ret; | |
165eee70 MD |
1290 | ret = wrapper_get_pfnblock_flags_mask_init(); |
1291 | if (ret) | |
1292 | return ret; | |
20591cf7 MD |
1293 | ret = lttng_tracepoint_init(); |
1294 | if (ret) | |
1295 | return ret; | |
a90917c3 | 1296 | event_cache = KMEM_CACHE(lttng_event, 0); |
20591cf7 MD |
1297 | if (!event_cache) { |
1298 | ret = -ENOMEM; | |
1299 | goto error_kmem; | |
1300 | } | |
80996790 | 1301 | ret = lttng_abi_init(); |
02119ee5 MD |
1302 | if (ret) |
1303 | goto error_abi; | |
0c956676 MD |
1304 | ret = lttng_logger_init(); |
1305 | if (ret) | |
1306 | goto error_logger; | |
4e3c1b9b | 1307 | return 0; |
0c956676 MD |
1308 | |
1309 | error_logger: | |
1310 | lttng_abi_exit(); | |
02119ee5 | 1311 | error_abi: |
1c25284c | 1312 | kmem_cache_destroy(event_cache); |
20591cf7 MD |
1313 | error_kmem: |
1314 | lttng_tracepoint_exit(); | |
1c25284c | 1315 | return ret; |
4e3c1b9b MD |
1316 | } |
1317 | ||
a90917c3 | 1318 | module_init(lttng_events_init); |
11b5a3c2 | 1319 | |
a90917c3 | 1320 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 1321 | { |
a90917c3 | 1322 | struct lttng_session *session, *tmpsession; |
92e94819 | 1323 | |
0c956676 | 1324 | lttng_logger_exit(); |
80996790 | 1325 | lttng_abi_exit(); |
92e94819 | 1326 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 1327 | lttng_session_destroy(session); |
11b5a3c2 | 1328 | kmem_cache_destroy(event_cache); |
20591cf7 | 1329 | lttng_tracepoint_exit(); |
4e3c1b9b | 1330 | } |
92e94819 | 1331 | |
a90917c3 | 1332 | module_exit(lttng_events_exit); |
11b5a3c2 | 1333 | |
92e94819 MD |
1334 | MODULE_LICENSE("GPL and additional rights"); |
1335 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
1336 | MODULE_DESCRIPTION("LTTng Events"); | |
9a9973ef MD |
1337 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
1338 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
309370e2 MD |
1339 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
1340 | LTTNG_MODULES_EXTRAVERSION); |