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