Commit | Line | Data |
---|---|---|
4e3c1b9b | 1 | /* |
a90917c3 | 2 | * lttng-events.c |
4e3c1b9b | 3 | * |
4e3c1b9b | 4 | * Holds LTTng per-session event registry. |
17baffe2 | 5 | * |
886d51a3 MD |
6 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
7 | * | |
8 | * This library is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU Lesser General Public | |
10 | * License as published by the Free Software Foundation; only | |
11 | * version 2.1 of the License. | |
12 | * | |
13 | * This library is distributed in the hope that it will be useful, | |
14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | * Lesser General Public License for more details. | |
17 | * | |
18 | * You should have received a copy of the GNU Lesser General Public | |
19 | * License along with this library; if not, write to the Free Software | |
20 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
4e3c1b9b MD |
21 | */ |
22 | ||
23 | #include <linux/module.h> | |
c0e31d2e MD |
24 | #include <linux/list.h> |
25 | #include <linux/mutex.h> | |
26 | #include <linux/sched.h> | |
11b5a3c2 | 27 | #include <linux/slab.h> |
c099397a | 28 | #include <linux/jiffies.h> |
99dc9597 | 29 | #include <linux/utsname.h> |
abc0446a | 30 | #include <linux/err.h> |
a864fb02 | 31 | #include "wrapper/uuid.h" |
b13f3ebe | 32 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
a82c63f1 | 33 | #include "wrapper/random.h" |
3a523f5b | 34 | #include "wrapper/tracepoint.h" |
b8590f40 | 35 | #include "lttng-kernel-version.h" |
a90917c3 MD |
36 | #include "lttng-events.h" |
37 | #include "lttng-tracer.h" | |
6dccd6c1 | 38 | #include "lttng-abi-old.h" |
4e3c1b9b | 39 | |
d83004aa JD |
40 | #define METADATA_CACHE_DEFAULT_SIZE 4096 |
41 | ||
4e3c1b9b | 42 | static LIST_HEAD(sessions); |
a90917c3 | 43 | static LIST_HEAD(lttng_transport_list); |
d83004aa JD |
44 | /* |
45 | * Protect the sessions and metadata caches. | |
46 | */ | |
4e3c1b9b MD |
47 | static DEFINE_MUTEX(sessions_mutex); |
48 | static struct kmem_cache *event_cache; | |
49 | ||
a90917c3 MD |
50 | static void _lttng_event_destroy(struct lttng_event *event); |
51 | static void _lttng_channel_destroy(struct lttng_channel *chan); | |
52 | static int _lttng_event_unregister(struct lttng_event *event); | |
c099397a | 53 | static |
a90917c3 MD |
54 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
55 | struct lttng_channel *chan, | |
56 | struct lttng_event *event); | |
c099397a | 57 | static |
a90917c3 | 58 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
d83004aa JD |
59 | static |
60 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream); | |
c099397a | 61 | |
c099397a | 62 | void synchronize_trace(void) |
abcca994 MD |
63 | { |
64 | synchronize_sched(); | |
b8590f40 MD |
65 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
66 | #ifdef CONFIG_PREEMPT_RT_FULL | |
67 | synchronize_rcu(); | |
68 | #endif | |
69 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ | |
abcca994 MD |
70 | #ifdef CONFIG_PREEMPT_RT |
71 | synchronize_rcu(); | |
72 | #endif | |
b8590f40 | 73 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
abcca994 MD |
74 | } |
75 | ||
a90917c3 | 76 | struct lttng_session *lttng_session_create(void) |
4e3c1b9b | 77 | { |
a90917c3 | 78 | struct lttng_session *session; |
d83004aa | 79 | struct lttng_metadata_cache *metadata_cache; |
4e3c1b9b MD |
80 | |
81 | mutex_lock(&sessions_mutex); | |
a90917c3 | 82 | session = kzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
4e3c1b9b | 83 | if (!session) |
d83004aa | 84 | goto err; |
4e3c1b9b | 85 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 86 | INIT_LIST_HEAD(&session->events); |
d793d5e1 | 87 | uuid_le_gen(&session->uuid); |
d83004aa JD |
88 | |
89 | metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache), | |
90 | GFP_KERNEL); | |
91 | if (!metadata_cache) | |
92 | goto err_free_session; | |
93 | metadata_cache->data = kzalloc(METADATA_CACHE_DEFAULT_SIZE, | |
94 | GFP_KERNEL); | |
95 | if (!metadata_cache->data) | |
96 | goto err_free_cache; | |
97 | metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE; | |
98 | kref_init(&metadata_cache->refcount); | |
99 | session->metadata_cache = metadata_cache; | |
100 | INIT_LIST_HEAD(&metadata_cache->metadata_stream); | |
a36580d5 MD |
101 | memcpy(&metadata_cache->uuid, &session->uuid, |
102 | sizeof(metadata_cache->uuid)); | |
4e3c1b9b MD |
103 | list_add(&session->list, &sessions); |
104 | mutex_unlock(&sessions_mutex); | |
105 | return session; | |
d83004aa JD |
106 | |
107 | err_free_cache: | |
108 | kfree(metadata_cache); | |
109 | err_free_session: | |
110 | kfree(session); | |
111 | err: | |
112 | mutex_unlock(&sessions_mutex); | |
113 | return NULL; | |
114 | } | |
115 | ||
116 | void metadata_cache_destroy(struct kref *kref) | |
117 | { | |
118 | struct lttng_metadata_cache *cache = | |
119 | container_of(kref, struct lttng_metadata_cache, refcount); | |
120 | kfree(cache->data); | |
121 | kfree(cache); | |
4e3c1b9b MD |
122 | } |
123 | ||
a90917c3 | 124 | void lttng_session_destroy(struct lttng_session *session) |
4e3c1b9b | 125 | { |
a90917c3 MD |
126 | struct lttng_channel *chan, *tmpchan; |
127 | struct lttng_event *event, *tmpevent; | |
d83004aa | 128 | struct lttng_metadata_stream *metadata_stream; |
dda6a249 | 129 | int ret; |
4e3c1b9b MD |
130 | |
131 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 132 | ACCESS_ONCE(session->active) = 0; |
1ec65de1 MD |
133 | list_for_each_entry(chan, &session->chan, list) { |
134 | ret = lttng_syscalls_unregister(chan); | |
135 | WARN_ON(ret); | |
136 | } | |
dda6a249 | 137 | list_for_each_entry(event, &session->events, list) { |
a90917c3 | 138 | ret = _lttng_event_unregister(event); |
dda6a249 MD |
139 | WARN_ON(ret); |
140 | } | |
abcca994 | 141 | synchronize_trace(); /* Wait for in-flight events to complete */ |
4e3c1b9b | 142 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
a90917c3 | 143 | _lttng_event_destroy(event); |
d83004aa JD |
144 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) { |
145 | BUG_ON(chan->channel_type == METADATA_CHANNEL); | |
a90917c3 | 146 | _lttng_channel_destroy(chan); |
d83004aa JD |
147 | } |
148 | list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list) | |
149 | _lttng_metadata_channel_hangup(metadata_stream); | |
e0130fab MD |
150 | if (session->pid_tracker) |
151 | lttng_pid_tracker_destroy(session->pid_tracker); | |
d83004aa | 152 | kref_put(&session->metadata_cache->refcount, metadata_cache_destroy); |
4e3c1b9b MD |
153 | list_del(&session->list); |
154 | mutex_unlock(&sessions_mutex); | |
155 | kfree(session); | |
156 | } | |
157 | ||
a90917c3 | 158 | int lttng_session_enable(struct lttng_session *session) |
c0e31d2e MD |
159 | { |
160 | int ret = 0; | |
a90917c3 | 161 | struct lttng_channel *chan; |
c0e31d2e MD |
162 | |
163 | mutex_lock(&sessions_mutex); | |
164 | if (session->active) { | |
165 | ret = -EBUSY; | |
166 | goto end; | |
167 | } | |
c099397a MD |
168 | |
169 | /* | |
170 | * Snapshot the number of events per channel to know the type of header | |
171 | * we need to use. | |
172 | */ | |
173 | list_for_each_entry(chan, &session->chan, list) { | |
174 | if (chan->header_type) | |
175 | continue; /* don't change it if session stop/restart */ | |
176 | if (chan->free_event_id < 31) | |
177 | chan->header_type = 1; /* compact */ | |
178 | else | |
179 | chan->header_type = 2; /* large */ | |
180 | } | |
181 | ||
52fc2e1f | 182 | ACCESS_ONCE(session->active) = 1; |
8070f5c0 | 183 | ACCESS_ONCE(session->been_active) = 1; |
a90917c3 | 184 | ret = _lttng_session_metadata_statedump(session); |
c337ddc2 MD |
185 | if (ret) { |
186 | ACCESS_ONCE(session->active) = 0; | |
187 | goto end; | |
188 | } | |
189 | ret = lttng_statedump_start(session); | |
360f38ea | 190 | if (ret) |
c099397a | 191 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
192 | end: |
193 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 194 | return ret; |
c0e31d2e MD |
195 | } |
196 | ||
a90917c3 | 197 | int lttng_session_disable(struct lttng_session *session) |
c0e31d2e MD |
198 | { |
199 | int ret = 0; | |
200 | ||
201 | mutex_lock(&sessions_mutex); | |
202 | if (!session->active) { | |
203 | ret = -EBUSY; | |
204 | goto end; | |
205 | } | |
52fc2e1f | 206 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
207 | end: |
208 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 209 | return ret; |
c0e31d2e MD |
210 | } |
211 | ||
a90917c3 | 212 | int lttng_channel_enable(struct lttng_channel *channel) |
e64957da MD |
213 | { |
214 | int old; | |
215 | ||
d83004aa | 216 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 217 | return -EPERM; |
e64957da MD |
218 | old = xchg(&channel->enabled, 1); |
219 | if (old) | |
220 | return -EEXIST; | |
221 | return 0; | |
222 | } | |
223 | ||
a90917c3 | 224 | int lttng_channel_disable(struct lttng_channel *channel) |
e64957da MD |
225 | { |
226 | int old; | |
227 | ||
d83004aa | 228 | if (channel->channel_type == METADATA_CHANNEL) |
c6485006 | 229 | return -EPERM; |
e64957da MD |
230 | old = xchg(&channel->enabled, 0); |
231 | if (!old) | |
232 | return -EEXIST; | |
233 | return 0; | |
234 | } | |
235 | ||
a90917c3 | 236 | int lttng_event_enable(struct lttng_event *event) |
e64957da MD |
237 | { |
238 | int old; | |
239 | ||
d83004aa | 240 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 241 | return -EPERM; |
e64957da MD |
242 | old = xchg(&event->enabled, 1); |
243 | if (old) | |
244 | return -EEXIST; | |
245 | return 0; | |
246 | } | |
247 | ||
a90917c3 | 248 | int lttng_event_disable(struct lttng_event *event) |
e64957da MD |
249 | { |
250 | int old; | |
251 | ||
d83004aa | 252 | if (event->chan->channel_type == METADATA_CHANNEL) |
c6485006 | 253 | return -EPERM; |
e64957da MD |
254 | old = xchg(&event->enabled, 0); |
255 | if (!old) | |
256 | return -EEXIST; | |
257 | return 0; | |
258 | } | |
259 | ||
a90917c3 | 260 | static struct lttng_transport *lttng_transport_find(const char *name) |
f3d01b96 | 261 | { |
a90917c3 | 262 | struct lttng_transport *transport; |
f3d01b96 | 263 | |
a90917c3 | 264 | list_for_each_entry(transport, <tng_transport_list, node) { |
f3d01b96 MD |
265 | if (!strcmp(transport->name, name)) |
266 | return transport; | |
267 | } | |
268 | return NULL; | |
269 | } | |
270 | ||
a90917c3 | 271 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
5dbbdb43 MD |
272 | const char *transport_name, |
273 | void *buf_addr, | |
4e3c1b9b MD |
274 | size_t subbuf_size, size_t num_subbuf, |
275 | unsigned int switch_timer_interval, | |
d83004aa JD |
276 | unsigned int read_timer_interval, |
277 | enum channel_type channel_type) | |
4e3c1b9b | 278 | { |
a90917c3 MD |
279 | struct lttng_channel *chan; |
280 | struct lttng_transport *transport = NULL; | |
4e3c1b9b MD |
281 | |
282 | mutex_lock(&sessions_mutex); | |
d83004aa | 283 | if (session->been_active && channel_type != METADATA_CHANNEL) |
e5382b6d | 284 | goto active; /* Refuse to add channel to active session */ |
a90917c3 | 285 | transport = lttng_transport_find(transport_name); |
f3d01b96 MD |
286 | if (!transport) { |
287 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
288 | transport_name); | |
c0e31d2e | 289 | goto notransport; |
f3d01b96 | 290 | } |
a33c9927 MD |
291 | if (!try_module_get(transport->owner)) { |
292 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
293 | goto notransport; | |
294 | } | |
a90917c3 | 295 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
4e3c1b9b | 296 | if (!chan) |
c0e31d2e | 297 | goto nomem; |
4e3c1b9b | 298 | chan->session = session; |
05d32c64 | 299 | chan->id = session->free_chan_id++; |
3b731ab1 | 300 | chan->ops = &transport->ops; |
125b4df4 MD |
301 | /* |
302 | * Note: the channel creation op already writes into the packet | |
303 | * headers. Therefore the "chan" information used as input | |
304 | * should be already accessible. | |
305 | */ | |
5f5ddf01 MD |
306 | chan->chan = transport->ops.channel_create(transport_name, |
307 | chan, buf_addr, subbuf_size, num_subbuf, | |
308 | switch_timer_interval, read_timer_interval); | |
f3d01b96 MD |
309 | if (!chan->chan) |
310 | goto create_error; | |
e64957da | 311 | chan->enabled = 1; |
a33c9927 | 312 | chan->transport = transport; |
d83004aa | 313 | chan->channel_type = channel_type; |
4e3c1b9b MD |
314 | list_add(&chan->list, &session->chan); |
315 | mutex_unlock(&sessions_mutex); | |
316 | return chan; | |
317 | ||
f3d01b96 MD |
318 | create_error: |
319 | kfree(chan); | |
c0e31d2e | 320 | nomem: |
a33c9927 MD |
321 | if (transport) |
322 | module_put(transport->owner); | |
c0e31d2e | 323 | notransport: |
e5382b6d | 324 | active: |
4e3c1b9b MD |
325 | mutex_unlock(&sessions_mutex); |
326 | return NULL; | |
327 | } | |
328 | ||
329 | /* | |
d83004aa JD |
330 | * Only used internally at session destruction for per-cpu channels, and |
331 | * when metadata channel is released. | |
332 | * Needs to be called with sessions mutex held. | |
4e3c1b9b | 333 | */ |
aa7c23a9 | 334 | static |
a90917c3 | 335 | void _lttng_channel_destroy(struct lttng_channel *chan) |
4e3c1b9b | 336 | { |
11b5a3c2 | 337 | chan->ops->channel_destroy(chan->chan); |
a33c9927 | 338 | module_put(chan->transport->owner); |
4e3c1b9b | 339 | list_del(&chan->list); |
8070f5c0 | 340 | lttng_destroy_context(chan->ctx); |
4e3c1b9b MD |
341 | kfree(chan); |
342 | } | |
343 | ||
d83004aa JD |
344 | void lttng_metadata_channel_destroy(struct lttng_channel *chan) |
345 | { | |
346 | BUG_ON(chan->channel_type != METADATA_CHANNEL); | |
347 | ||
348 | /* Protect the metadata cache with the sessions_mutex. */ | |
349 | mutex_lock(&sessions_mutex); | |
350 | _lttng_channel_destroy(chan); | |
351 | mutex_unlock(&sessions_mutex); | |
352 | } | |
353 | EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy); | |
354 | ||
355 | static | |
356 | void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream) | |
357 | { | |
358 | stream->finalized = 1; | |
359 | wake_up_interruptible(&stream->read_wait); | |
360 | } | |
361 | ||
e5382b6d MD |
362 | /* |
363 | * Supports event creation while tracing session is active. | |
364 | */ | |
a90917c3 | 365 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
d6d808f3 | 366 | struct lttng_kernel_event *event_param, |
259b6cb3 MD |
367 | void *filter, |
368 | const struct lttng_event_desc *internal_desc) | |
4e3c1b9b | 369 | { |
a90917c3 | 370 | struct lttng_event *event; |
3d084699 | 371 | int ret; |
4e3c1b9b MD |
372 | |
373 | mutex_lock(&sessions_mutex); | |
abc0446a | 374 | if (chan->free_event_id == -1U) { |
4cf0bf51 | 375 | ret = -EMFILE; |
e5382b6d | 376 | goto full; |
abc0446a | 377 | } |
4e3c1b9b | 378 | /* |
dda6a249 MD |
379 | * This is O(n^2) (for each event, the loop is called at event |
380 | * creation). Might require a hash if we have lots of events. | |
4e3c1b9b | 381 | */ |
abc0446a MD |
382 | list_for_each_entry(event, &chan->session->events, list) { |
383 | if (!strcmp(event->desc->name, event_param->name)) { | |
f046a95d MD |
384 | /* |
385 | * Allow events with the same name to appear in | |
386 | * different channels. | |
387 | */ | |
388 | if (event->chan == chan) { | |
389 | ret = -EEXIST; | |
390 | goto exist; | |
391 | } | |
abc0446a MD |
392 | } |
393 | } | |
11b5a3c2 | 394 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
abc0446a | 395 | if (!event) { |
4cf0bf51 | 396 | ret = -ENOMEM; |
4e3c1b9b | 397 | goto cache_error; |
abc0446a | 398 | } |
4e3c1b9b MD |
399 | event->chan = chan; |
400 | event->filter = filter; | |
e5382b6d | 401 | event->id = chan->free_event_id++; |
e64957da | 402 | event->enabled = 1; |
d6d808f3 | 403 | event->instrumentation = event_param->instrumentation; |
a90917c3 | 404 | /* Populate lttng_event structure before tracepoint registration. */ |
e5382b6d | 405 | smp_wmb(); |
d6d808f3 | 406 | switch (event_param->instrumentation) { |
ab2277d6 | 407 | case LTTNG_KERNEL_TRACEPOINT: |
a90917c3 | 408 | event->desc = lttng_event_get(event_param->name); |
abc0446a | 409 | if (!event->desc) { |
4cf0bf51 | 410 | ret = -ENOENT; |
d3dbe23c | 411 | goto register_error; |
abc0446a | 412 | } |
20591cf7 | 413 | ret = lttng_wrapper_tracepoint_probe_register(event->desc->kname, |
d3dbe23c MD |
414 | event->desc->probe_callback, |
415 | event); | |
abc0446a | 416 | if (ret) { |
4cf0bf51 | 417 | ret = -EINVAL; |
11b5a3c2 | 418 | goto register_error; |
abc0446a | 419 | } |
baf20995 | 420 | break; |
ab2277d6 | 421 | case LTTNG_KERNEL_KPROBE: |
30bdb6e4 | 422 | ret = lttng_kprobes_register(event_param->name, |
f17701fb MD |
423 | event_param->u.kprobe.symbol_name, |
424 | event_param->u.kprobe.offset, | |
425 | event_param->u.kprobe.addr, | |
426 | event); | |
abc0446a | 427 | if (ret) { |
4cf0bf51 | 428 | ret = -EINVAL; |
d6d808f3 | 429 | goto register_error; |
abc0446a | 430 | } |
edeb3137 MD |
431 | ret = try_module_get(event->desc->owner); |
432 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 433 | break; |
7371f44c MD |
434 | case LTTNG_KERNEL_KRETPROBE: |
435 | { | |
a90917c3 | 436 | struct lttng_event *event_return; |
7371f44c MD |
437 | |
438 | /* kretprobe defines 2 events */ | |
439 | event_return = | |
440 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
abc0446a | 441 | if (!event_return) { |
4cf0bf51 | 442 | ret = -ENOMEM; |
7371f44c | 443 | goto register_error; |
abc0446a | 444 | } |
7371f44c MD |
445 | event_return->chan = chan; |
446 | event_return->filter = filter; | |
447 | event_return->id = chan->free_event_id++; | |
448 | event_return->enabled = 1; | |
449 | event_return->instrumentation = event_param->instrumentation; | |
450 | /* | |
a90917c3 | 451 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
452 | */ |
453 | smp_wmb(); | |
454 | ret = lttng_kretprobes_register(event_param->name, | |
455 | event_param->u.kretprobe.symbol_name, | |
456 | event_param->u.kretprobe.offset, | |
457 | event_param->u.kretprobe.addr, | |
458 | event, event_return); | |
459 | if (ret) { | |
460 | kmem_cache_free(event_cache, event_return); | |
4cf0bf51 | 461 | ret = -EINVAL; |
7371f44c MD |
462 | goto register_error; |
463 | } | |
464 | /* Take 2 refs on the module: one per event. */ | |
465 | ret = try_module_get(event->desc->owner); | |
466 | WARN_ON_ONCE(!ret); | |
467 | ret = try_module_get(event->desc->owner); | |
468 | WARN_ON_ONCE(!ret); | |
a90917c3 | 469 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c | 470 | event_return); |
abc0446a | 471 | WARN_ON_ONCE(ret > 0); |
7371f44c MD |
472 | if (ret) { |
473 | kmem_cache_free(event_cache, event_return); | |
474 | module_put(event->desc->owner); | |
475 | module_put(event->desc->owner); | |
476 | goto statedump_error; | |
477 | } | |
478 | list_add(&event_return->list, &chan->session->events); | |
479 | break; | |
480 | } | |
ab2277d6 | 481 | case LTTNG_KERNEL_FUNCTION: |
30bdb6e4 | 482 | ret = lttng_ftrace_register(event_param->name, |
e0a7a7c4 MD |
483 | event_param->u.ftrace.symbol_name, |
484 | event); | |
abc0446a | 485 | if (ret) { |
e0a7a7c4 | 486 | goto register_error; |
abc0446a | 487 | } |
edeb3137 MD |
488 | ret = try_module_get(event->desc->owner); |
489 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 490 | break; |
1ec65de1 | 491 | case LTTNG_KERNEL_NOOP: |
259b6cb3 | 492 | event->desc = internal_desc; |
abc0446a | 493 | if (!event->desc) { |
4cf0bf51 | 494 | ret = -EINVAL; |
259b6cb3 | 495 | goto register_error; |
abc0446a | 496 | } |
1ec65de1 | 497 | break; |
baf20995 MD |
498 | default: |
499 | WARN_ON_ONCE(1); | |
4cf0bf51 | 500 | ret = -EINVAL; |
df07930b | 501 | goto register_error; |
baf20995 | 502 | } |
a90917c3 | 503 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
abc0446a MD |
504 | WARN_ON_ONCE(ret > 0); |
505 | if (ret) { | |
c099397a | 506 | goto statedump_error; |
abc0446a | 507 | } |
dda6a249 | 508 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 509 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
510 | return event; |
511 | ||
c099397a | 512 | statedump_error: |
259b6cb3 | 513 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 514 | register_error: |
11b5a3c2 | 515 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
516 | cache_error: |
517 | exist: | |
e5382b6d | 518 | full: |
4e3c1b9b | 519 | mutex_unlock(&sessions_mutex); |
4cf0bf51 | 520 | return ERR_PTR(ret); |
4e3c1b9b MD |
521 | } |
522 | ||
523 | /* | |
524 | * Only used internally at session destruction. | |
525 | */ | |
a90917c3 | 526 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 527 | { |
11b5a3c2 MD |
528 | int ret = -EINVAL; |
529 | ||
38d024ae | 530 | switch (event->instrumentation) { |
ab2277d6 | 531 | case LTTNG_KERNEL_TRACEPOINT: |
20591cf7 | 532 | ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname, |
85a9ca7f | 533 | event->desc->probe_callback, |
11b5a3c2 MD |
534 | event); |
535 | if (ret) | |
536 | return ret; | |
baf20995 | 537 | break; |
ab2277d6 | 538 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 539 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
540 | ret = 0; |
541 | break; | |
7371f44c MD |
542 | case LTTNG_KERNEL_KRETPROBE: |
543 | lttng_kretprobes_unregister(event); | |
544 | ret = 0; | |
545 | break; | |
ab2277d6 | 546 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
547 | lttng_ftrace_unregister(event); |
548 | ret = 0; | |
549 | break; | |
259b6cb3 MD |
550 | case LTTNG_KERNEL_NOOP: |
551 | ret = 0; | |
552 | break; | |
baf20995 MD |
553 | default: |
554 | WARN_ON_ONCE(1); | |
555 | } | |
dda6a249 MD |
556 | return ret; |
557 | } | |
558 | ||
559 | /* | |
560 | * Only used internally at session destruction. | |
561 | */ | |
be066e6c | 562 | static |
a90917c3 | 563 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 564 | { |
edeb3137 MD |
565 | switch (event->instrumentation) { |
566 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 567 | lttng_event_put(event->desc); |
edeb3137 MD |
568 | break; |
569 | case LTTNG_KERNEL_KPROBE: | |
570 | module_put(event->desc->owner); | |
571 | lttng_kprobes_destroy_private(event); | |
572 | break; | |
7371f44c MD |
573 | case LTTNG_KERNEL_KRETPROBE: |
574 | module_put(event->desc->owner); | |
575 | lttng_kretprobes_destroy_private(event); | |
576 | break; | |
edeb3137 MD |
577 | case LTTNG_KERNEL_FUNCTION: |
578 | module_put(event->desc->owner); | |
579 | lttng_ftrace_destroy_private(event); | |
580 | break; | |
259b6cb3 MD |
581 | case LTTNG_KERNEL_NOOP: |
582 | break; | |
edeb3137 MD |
583 | default: |
584 | WARN_ON_ONCE(1); | |
585 | } | |
dda6a249 | 586 | list_del(&event->list); |
8070f5c0 | 587 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 588 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
589 | } |
590 | ||
e0130fab MD |
591 | int lttng_session_track_pid(struct lttng_session *session, int pid) |
592 | { | |
593 | int ret; | |
594 | ||
595 | if (pid < -1) | |
596 | return -EINVAL; | |
597 | mutex_lock(&sessions_mutex); | |
598 | if (pid == -1) { | |
599 | /* track all pids: destroy tracker. */ | |
600 | if (session->pid_tracker) { | |
601 | struct lttng_pid_tracker *lpf; | |
602 | ||
603 | lpf = session->pid_tracker; | |
604 | rcu_assign_pointer(session->pid_tracker, NULL); | |
605 | synchronize_trace(); | |
606 | lttng_pid_tracker_destroy(lpf); | |
607 | } | |
608 | ret = 0; | |
609 | } else { | |
610 | if (!session->pid_tracker) { | |
611 | struct lttng_pid_tracker *lpf; | |
612 | ||
613 | lpf = lttng_pid_tracker_create(); | |
614 | if (!lpf) { | |
615 | ret = -ENOMEM; | |
616 | goto unlock; | |
617 | } | |
618 | ret = lttng_pid_tracker_add(lpf, pid); | |
619 | rcu_assign_pointer(session->pid_tracker, lpf); | |
620 | } else { | |
621 | ret = lttng_pid_tracker_add(session->pid_tracker, pid); | |
622 | } | |
623 | } | |
624 | unlock: | |
625 | mutex_unlock(&sessions_mutex); | |
626 | return ret; | |
627 | } | |
628 | ||
629 | int lttng_session_untrack_pid(struct lttng_session *session, int pid) | |
630 | { | |
631 | int ret; | |
632 | ||
633 | if (pid < -1) | |
634 | return -EINVAL; | |
635 | mutex_lock(&sessions_mutex); | |
636 | if (pid == -1) { | |
637 | /* untrack all pids: replace by empty tracker. */ | |
638 | struct lttng_pid_tracker *old_lpf = session->pid_tracker; | |
639 | struct lttng_pid_tracker *lpf; | |
640 | ||
641 | lpf = lttng_pid_tracker_create(); | |
642 | if (!lpf) { | |
643 | ret = -ENOMEM; | |
644 | goto unlock; | |
645 | } | |
646 | rcu_assign_pointer(session->pid_tracker, lpf); | |
647 | synchronize_trace(); | |
648 | if (old_lpf) | |
649 | lttng_pid_tracker_destroy(old_lpf); | |
650 | ret = 0; | |
651 | } else { | |
652 | if (!session->pid_tracker) { | |
653 | ret = -ENOENT; | |
654 | goto unlock; | |
655 | } | |
656 | ret = lttng_pid_tracker_del(session->pid_tracker, pid); | |
657 | } | |
658 | unlock: | |
659 | mutex_unlock(&sessions_mutex); | |
660 | return ret; | |
661 | } | |
662 | ||
1ec3f75a | 663 | /* |
d83004aa JD |
664 | * Serialize at most one packet worth of metadata into a metadata |
665 | * channel. | |
1ec3f75a MD |
666 | * We have exclusive access to our metadata buffer (protected by the |
667 | * sessions_mutex), so we can do racy operations such as looking for | |
668 | * remaining space left in packet and write, since mutual exclusion | |
669 | * protects us from concurrent writes. | |
35097f36 JD |
670 | * Returns the number of bytes written in the channel, 0 if no data |
671 | * was written and a negative value on error. | |
1ec3f75a | 672 | */ |
b3b8072b MD |
673 | int lttng_metadata_output_channel(struct lttng_metadata_stream *stream, |
674 | struct channel *chan) | |
d83004aa JD |
675 | { |
676 | struct lib_ring_buffer_ctx ctx; | |
677 | int ret = 0; | |
678 | size_t len, reserve_len; | |
679 | ||
f613e3e6 MD |
680 | /* |
681 | * Ensure we support mutiple get_next / put sequences followed | |
de23d59d MD |
682 | * by put_next. The metadata stream lock internally protects |
683 | * reading the metadata cache. It can indeed be read | |
684 | * concurrently by "get_next_subbuf" and "flush" operations on | |
685 | * the buffer invoked by different processes. | |
f613e3e6 | 686 | */ |
de23d59d | 687 | mutex_lock(&stream->lock); |
f613e3e6 MD |
688 | WARN_ON(stream->metadata_in < stream->metadata_out); |
689 | if (stream->metadata_in != stream->metadata_out) | |
de23d59d | 690 | goto end; |
f613e3e6 | 691 | |
d83004aa | 692 | len = stream->metadata_cache->metadata_written - |
f613e3e6 | 693 | stream->metadata_in; |
9de2c215 | 694 | if (!len) |
de23d59d | 695 | goto end; |
d83004aa | 696 | reserve_len = min_t(size_t, |
b3b8072b | 697 | stream->transport->ops.packet_avail_size(chan), |
d83004aa | 698 | len); |
b3b8072b | 699 | lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len, |
d83004aa JD |
700 | sizeof(char), -1); |
701 | /* | |
702 | * If reservation failed, return an error to the caller. | |
703 | */ | |
b3b8072b | 704 | ret = stream->transport->ops.event_reserve(&ctx, 0); |
d83004aa JD |
705 | if (ret != 0) { |
706 | printk(KERN_WARNING "LTTng: Metadata event reservation failed\n"); | |
707 | goto end; | |
708 | } | |
b3b8072b | 709 | stream->transport->ops.event_write(&ctx, |
f613e3e6 | 710 | stream->metadata_cache->data + stream->metadata_in, |
d83004aa | 711 | reserve_len); |
b3b8072b | 712 | stream->transport->ops.event_commit(&ctx); |
f613e3e6 | 713 | stream->metadata_in += reserve_len; |
d83004aa JD |
714 | ret = reserve_len; |
715 | ||
716 | end: | |
de23d59d | 717 | mutex_unlock(&stream->lock); |
d83004aa JD |
718 | return ret; |
719 | } | |
720 | ||
721 | /* | |
722 | * Write the metadata to the metadata cache. | |
723 | * Must be called with sessions_mutex held. | |
724 | */ | |
a90917c3 | 725 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
726 | const char *fmt, ...) |
727 | { | |
c099397a | 728 | char *str; |
d83004aa | 729 | size_t len; |
c099397a | 730 | va_list ap; |
d83004aa | 731 | struct lttng_metadata_stream *stream; |
c099397a MD |
732 | |
733 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
734 | ||
735 | va_start(ap, fmt); | |
736 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
737 | va_end(ap); | |
738 | if (!str) | |
739 | return -ENOMEM; | |
740 | ||
1ec3f75a | 741 | len = strlen(str); |
d83004aa JD |
742 | if (session->metadata_cache->metadata_written + len > |
743 | session->metadata_cache->cache_alloc) { | |
744 | char *tmp_cache_realloc; | |
745 | unsigned int tmp_cache_alloc_size; | |
746 | ||
747 | tmp_cache_alloc_size = max_t(unsigned int, | |
748 | session->metadata_cache->cache_alloc + len, | |
749 | session->metadata_cache->cache_alloc << 1); | |
750 | tmp_cache_realloc = krealloc(session->metadata_cache->data, | |
751 | tmp_cache_alloc_size, GFP_KERNEL); | |
752 | if (!tmp_cache_realloc) | |
753 | goto err; | |
754 | session->metadata_cache->cache_alloc = tmp_cache_alloc_size; | |
755 | session->metadata_cache->data = tmp_cache_realloc; | |
c099397a | 756 | } |
d83004aa JD |
757 | memcpy(session->metadata_cache->data + |
758 | session->metadata_cache->metadata_written, | |
759 | str, len); | |
760 | session->metadata_cache->metadata_written += len; | |
c099397a | 761 | kfree(str); |
d83004aa JD |
762 | |
763 | list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) | |
764 | wake_up_interruptible(&stream->read_wait); | |
765 | ||
766 | return 0; | |
767 | ||
768 | err: | |
769 | kfree(str); | |
770 | return -ENOMEM; | |
c099397a MD |
771 | } |
772 | ||
d83004aa JD |
773 | /* |
774 | * Must be called with sessions_mutex held. | |
775 | */ | |
c099397a | 776 | static |
a90917c3 | 777 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 778 | const struct lttng_event_field *field) |
c099397a | 779 | { |
c099397a | 780 | int ret = 0; |
c099397a | 781 | |
8070f5c0 MD |
782 | switch (field->type.atype) { |
783 | case atype_integer: | |
784 | ret = lttng_metadata_printf(session, | |
244465ab | 785 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
786 | field->type.u.basic.integer.size, |
787 | field->type.u.basic.integer.alignment, | |
788 | field->type.u.basic.integer.signedness, | |
789 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
790 | ? "none" | |
791 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
792 | ? "UTF8" | |
793 | : "ASCII", | |
794 | field->type.u.basic.integer.base, | |
c099397a | 795 | #ifdef __BIG_ENDIAN |
8070f5c0 | 796 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 797 | #else |
8070f5c0 | 798 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 799 | #endif |
8070f5c0 MD |
800 | field->name); |
801 | break; | |
802 | case atype_enum: | |
803 | ret = lttng_metadata_printf(session, | |
244465ab | 804 | " %s _%s;\n", |
8070f5c0 MD |
805 | field->type.u.basic.enumeration.name, |
806 | field->name); | |
807 | break; | |
808 | case atype_array: | |
809 | { | |
810 | const struct lttng_basic_type *elem_type; | |
811 | ||
812 | elem_type = &field->type.u.array.elem_type; | |
813 | ret = lttng_metadata_printf(session, | |
244465ab | 814 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
815 | elem_type->u.basic.integer.size, |
816 | elem_type->u.basic.integer.alignment, | |
817 | elem_type->u.basic.integer.signedness, | |
818 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
819 | ? "none" | |
820 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
821 | ? "UTF8" | |
822 | : "ASCII", | |
823 | elem_type->u.basic.integer.base, | |
8fa75f34 | 824 | #ifdef __BIG_ENDIAN |
8070f5c0 | 825 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 826 | #else |
8070f5c0 | 827 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 828 | #endif |
8070f5c0 MD |
829 | field->name, field->type.u.array.length); |
830 | break; | |
831 | } | |
832 | case atype_sequence: | |
833 | { | |
834 | const struct lttng_basic_type *elem_type; | |
835 | const struct lttng_basic_type *length_type; | |
836 | ||
837 | elem_type = &field->type.u.sequence.elem_type; | |
838 | length_type = &field->type.u.sequence.length_type; | |
839 | ret = lttng_metadata_printf(session, | |
840 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 841 | length_type->u.basic.integer.size, |
32257272 | 842 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
843 | length_type->u.basic.integer.signedness, |
844 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
845 | ? "none" | |
0635cdd4 | 846 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 847 | ? "UTF8" |
0635cdd4 | 848 | : "ASCII"), |
8070f5c0 | 849 | length_type->u.basic.integer.base, |
e0a7a7c4 | 850 | #ifdef __BIG_ENDIAN |
8070f5c0 | 851 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 852 | #else |
0635cdd4 | 853 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 854 | #endif |
27d2368e MD |
855 | field->name); |
856 | if (ret) | |
857 | return ret; | |
858 | ||
859 | ret = lttng_metadata_printf(session, | |
244465ab | 860 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 861 | elem_type->u.basic.integer.size, |
32257272 | 862 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
863 | elem_type->u.basic.integer.signedness, |
864 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
865 | ? "none" | |
0635cdd4 | 866 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 867 | ? "UTF8" |
0635cdd4 | 868 | : "ASCII"), |
8070f5c0 | 869 | elem_type->u.basic.integer.base, |
8fa75f34 | 870 | #ifdef __BIG_ENDIAN |
8070f5c0 | 871 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 872 | #else |
8070f5c0 | 873 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 874 | #endif |
8070f5c0 | 875 | field->name, |
27d2368e | 876 | field->name); |
8070f5c0 MD |
877 | break; |
878 | } | |
c099397a | 879 | |
8070f5c0 MD |
880 | case atype_string: |
881 | /* Default encoding is UTF8 */ | |
882 | ret = lttng_metadata_printf(session, | |
244465ab | 883 | " string%s _%s;\n", |
8070f5c0 MD |
884 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
885 | " { encoding = ASCII; }" : "", | |
886 | field->name); | |
887 | break; | |
888 | default: | |
889 | WARN_ON_ONCE(1); | |
890 | return -EINVAL; | |
891 | } | |
892 | return ret; | |
893 | } | |
894 | ||
895 | static | |
a90917c3 | 896 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
897 | struct lttng_ctx *ctx) |
898 | { | |
899 | int ret = 0; | |
900 | int i; | |
901 | ||
902 | if (!ctx) | |
903 | return 0; | |
904 | for (i = 0; i < ctx->nr_fields; i++) { | |
905 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
906 | ||
a90917c3 | 907 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
908 | if (ret) |
909 | return ret; | |
910 | } | |
911 | return ret; | |
912 | } | |
913 | ||
914 | static | |
a90917c3 MD |
915 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
916 | struct lttng_event *event) | |
8070f5c0 MD |
917 | { |
918 | const struct lttng_event_desc *desc = event->desc; | |
919 | int ret = 0; | |
920 | int i; | |
921 | ||
922 | for (i = 0; i < desc->nr_fields; i++) { | |
923 | const struct lttng_event_field *field = &desc->fields[i]; | |
924 | ||
a90917c3 | 925 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
926 | if (ret) |
927 | return ret; | |
c099397a MD |
928 | } |
929 | return ret; | |
930 | } | |
931 | ||
d83004aa JD |
932 | /* |
933 | * Must be called with sessions_mutex held. | |
934 | */ | |
c099397a | 935 | static |
a90917c3 MD |
936 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
937 | struct lttng_channel *chan, | |
938 | struct lttng_event *event) | |
c099397a MD |
939 | { |
940 | int ret = 0; | |
941 | ||
942 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
943 | return 0; | |
d83004aa | 944 | if (chan->channel_type == METADATA_CHANNEL) |
c099397a MD |
945 | return 0; |
946 | ||
947 | ret = lttng_metadata_printf(session, | |
948 | "event {\n" | |
ae734547 | 949 | " name = \"%s\";\n" |
c099397a | 950 | " id = %u;\n" |
b9074a1b | 951 | " stream_id = %u;\n", |
c099397a MD |
952 | event->desc->name, |
953 | event->id, | |
954 | event->chan->id); | |
955 | if (ret) | |
956 | goto end; | |
957 | ||
b9074a1b MD |
958 | if (event->ctx) { |
959 | ret = lttng_metadata_printf(session, | |
960 | " context := struct {\n"); | |
961 | if (ret) | |
962 | goto end; | |
963 | } | |
a90917c3 | 964 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
965 | if (ret) |
966 | goto end; | |
b9074a1b MD |
967 | if (event->ctx) { |
968 | ret = lttng_metadata_printf(session, | |
969 | " };\n"); | |
970 | if (ret) | |
971 | goto end; | |
972 | } | |
8070f5c0 MD |
973 | |
974 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
975 | " fields := struct {\n" |
976 | ); | |
977 | if (ret) | |
978 | goto end; | |
979 | ||
a90917c3 | 980 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
981 | if (ret) |
982 | goto end; | |
983 | ||
984 | /* | |
985 | * LTTng space reservation can only reserve multiples of the | |
986 | * byte size. | |
987 | */ | |
988 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
989 | " };\n" |
990 | "};\n\n"); | |
c099397a MD |
991 | if (ret) |
992 | goto end; | |
993 | ||
c099397a MD |
994 | event->metadata_dumped = 1; |
995 | end: | |
996 | return ret; | |
997 | ||
998 | } | |
999 | ||
d83004aa JD |
1000 | /* |
1001 | * Must be called with sessions_mutex held. | |
1002 | */ | |
c099397a | 1003 | static |
a90917c3 MD |
1004 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
1005 | struct lttng_channel *chan) | |
c099397a MD |
1006 | { |
1007 | int ret = 0; | |
1008 | ||
1009 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
1010 | return 0; | |
d83004aa JD |
1011 | |
1012 | if (chan->channel_type == METADATA_CHANNEL) | |
c099397a MD |
1013 | return 0; |
1014 | ||
1015 | WARN_ON_ONCE(!chan->header_type); | |
1016 | ret = lttng_metadata_printf(session, | |
1017 | "stream {\n" | |
1018 | " id = %u;\n" | |
9115fbdc | 1019 | " event.header := %s;\n" |
b9074a1b | 1020 | " packet.context := struct packet_context;\n", |
c099397a MD |
1021 | chan->id, |
1022 | chan->header_type == 1 ? "struct event_header_compact" : | |
1023 | "struct event_header_large"); | |
1024 | if (ret) | |
1025 | goto end; | |
1026 | ||
b9074a1b MD |
1027 | if (chan->ctx) { |
1028 | ret = lttng_metadata_printf(session, | |
1029 | " event.context := struct {\n"); | |
1030 | if (ret) | |
1031 | goto end; | |
1032 | } | |
a90917c3 | 1033 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
1034 | if (ret) |
1035 | goto end; | |
b9074a1b MD |
1036 | if (chan->ctx) { |
1037 | ret = lttng_metadata_printf(session, | |
1038 | " };\n"); | |
1039 | if (ret) | |
1040 | goto end; | |
1041 | } | |
8070f5c0 MD |
1042 | |
1043 | ret = lttng_metadata_printf(session, | |
b9074a1b | 1044 | "};\n\n"); |
8070f5c0 | 1045 | |
c099397a MD |
1046 | chan->metadata_dumped = 1; |
1047 | end: | |
1048 | return ret; | |
1049 | } | |
1050 | ||
d83004aa JD |
1051 | /* |
1052 | * Must be called with sessions_mutex held. | |
1053 | */ | |
9115fbdc | 1054 | static |
a90917c3 | 1055 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
1056 | { |
1057 | return lttng_metadata_printf(session, | |
1058 | "struct packet_context {\n" | |
a3ccff4f MD |
1059 | " uint64_clock_monotonic_t timestamp_begin;\n" |
1060 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
1061 | " uint64_t content_size;\n" |
1062 | " uint64_t packet_size;\n" | |
a9afe705 | 1063 | " unsigned long events_discarded;\n" |
9115fbdc | 1064 | " uint32_t cpu_id;\n" |
c6dfdf6f | 1065 | "};\n\n" |
9115fbdc MD |
1066 | ); |
1067 | } | |
1068 | ||
1069 | /* | |
1070 | * Compact header: | |
1071 | * id: range: 0 - 30. | |
1072 | * id 31 is reserved to indicate an extended header. | |
1073 | * | |
1074 | * Large header: | |
1075 | * id: range: 0 - 65534. | |
1076 | * id 65535 is reserved to indicate an extended header. | |
d83004aa JD |
1077 | * |
1078 | * Must be called with sessions_mutex held. | |
9115fbdc MD |
1079 | */ |
1080 | static | |
a90917c3 | 1081 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
1082 | { |
1083 | return lttng_metadata_printf(session, | |
1084 | "struct event_header_compact {\n" | |
1085 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
1086 | " variant <id> {\n" | |
1087 | " struct {\n" | |
a3ccff4f | 1088 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1089 | " } compact;\n" |
1090 | " struct {\n" | |
1091 | " uint32_t id;\n" | |
a3ccff4f | 1092 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1093 | " } extended;\n" |
1094 | " } v;\n" | |
1095 | "} align(%u);\n" | |
1096 | "\n" | |
1097 | "struct event_header_large {\n" | |
1098 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
1099 | " variant <id> {\n" | |
1100 | " struct {\n" | |
a3ccff4f | 1101 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1102 | " } compact;\n" |
1103 | " struct {\n" | |
1104 | " uint32_t id;\n" | |
a3ccff4f | 1105 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
1106 | " } extended;\n" |
1107 | " } v;\n" | |
1108 | "} align(%u);\n\n", | |
a90917c3 MD |
1109 | lttng_alignof(uint32_t) * CHAR_BIT, |
1110 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
1111 | ); |
1112 | } | |
1113 | ||
a3ccff4f MD |
1114 | /* |
1115 | * Approximation of NTP time of day to clock monotonic correlation, | |
1116 | * taken at start of trace. | |
1117 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
1118 | * in future versions. | |
1119 | */ | |
1120 | static | |
1121 | uint64_t measure_clock_offset(void) | |
1122 | { | |
1123 | uint64_t offset, monotonic[2], realtime; | |
1124 | struct timespec rts = { 0, 0 }; | |
1125 | unsigned long flags; | |
1126 | ||
1127 | /* Disable interrupts to increase correlation precision. */ | |
1128 | local_irq_save(flags); | |
1129 | monotonic[0] = trace_clock_read64(); | |
1130 | getnstimeofday(&rts); | |
1131 | monotonic[1] = trace_clock_read64(); | |
1132 | local_irq_restore(flags); | |
1133 | ||
1134 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 1135 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
1136 | realtime += rts.tv_nsec; |
1137 | offset = realtime - offset; | |
1138 | return offset; | |
1139 | } | |
1140 | ||
c099397a MD |
1141 | /* |
1142 | * Output metadata into this session's metadata buffers. | |
d83004aa | 1143 | * Must be called with sessions_mutex held. |
c099397a MD |
1144 | */ |
1145 | static | |
a90917c3 | 1146 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 1147 | { |
30bdb6e4 | 1148 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 1149 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
1150 | struct lttng_channel *chan; |
1151 | struct lttng_event *event; | |
c099397a MD |
1152 | int ret = 0; |
1153 | ||
1154 | if (!ACCESS_ONCE(session->active)) | |
1155 | return 0; | |
1156 | if (session->metadata_dumped) | |
1157 | goto skip_session; | |
c099397a | 1158 | |
d793d5e1 | 1159 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
1160 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
1161 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
1162 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
1163 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
1164 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
1165 | |
1166 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
1167 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
1168 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
1169 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
1170 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 1171 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
1172 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
1173 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
1174 | "\n" |
1175 | "trace {\n" | |
1176 | " major = %u;\n" | |
1177 | " minor = %u;\n" | |
30bdb6e4 | 1178 | " uuid = \"%s\";\n" |
d793d5e1 MD |
1179 | " byte_order = %s;\n" |
1180 | " packet.header := struct {\n" | |
1181 | " uint32_t magic;\n" | |
1ec3f75a | 1182 | " uint8_t uuid[16];\n" |
d793d5e1 | 1183 | " uint32_t stream_id;\n" |
0eb25f58 | 1184 | " };\n" |
d793d5e1 | 1185 | "};\n\n", |
a90917c3 MD |
1186 | lttng_alignof(uint8_t) * CHAR_BIT, |
1187 | lttng_alignof(uint16_t) * CHAR_BIT, | |
1188 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1189 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
1190 | sizeof(unsigned long) * CHAR_BIT, |
1191 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
1192 | CTF_SPEC_MAJOR, |
1193 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
1194 | uuid_s, |
1195 | #ifdef __BIG_ENDIAN | |
1196 | "be" | |
1197 | #else | |
1198 | "le" | |
1199 | #endif | |
1200 | ); | |
1201 | if (ret) | |
1202 | goto end; | |
1203 | ||
99dc9597 MD |
1204 | ret = lttng_metadata_printf(session, |
1205 | "env {\n" | |
a6058143 | 1206 | " hostname = \"%s\";\n" |
c6c9e10f | 1207 | " domain = \"kernel\";\n" |
99dc9597 | 1208 | " sysname = \"%s\";\n" |
c6c9e10f MD |
1209 | " kernel_release = \"%s\";\n" |
1210 | " kernel_version = \"%s\";\n" | |
1211 | " tracer_name = \"lttng-modules\";\n" | |
1212 | " tracer_major = %d;\n" | |
1213 | " tracer_minor = %d;\n" | |
1214 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 1215 | "};\n\n", |
3d0d43db | 1216 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
1217 | utsname()->sysname, |
1218 | utsname()->release, | |
c6c9e10f MD |
1219 | utsname()->version, |
1220 | LTTNG_MODULES_MAJOR_VERSION, | |
1221 | LTTNG_MODULES_MINOR_VERSION, | |
1222 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
1223 | ); |
1224 | if (ret) | |
1225 | goto end; | |
1226 | ||
a3ccff4f MD |
1227 | ret = lttng_metadata_printf(session, |
1228 | "clock {\n" | |
a82c63f1 MD |
1229 | " name = %s;\n", |
1230 | "monotonic" | |
1231 | ); | |
1232 | if (ret) | |
1233 | goto end; | |
1234 | ||
1235 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1236 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1237 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1238 | clock_uuid_s |
1239 | ); | |
1240 | if (ret) | |
1241 | goto end; | |
1242 | } | |
1243 | ||
1244 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1245 | " description = \"Monotonic Clock\";\n" |
1246 | " freq = %llu; /* Frequency, in Hz */\n" | |
1247 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1248 | " offset = %llu;\n" | |
1249 | "};\n\n", | |
a3ccff4f MD |
1250 | (unsigned long long) trace_clock_freq(), |
1251 | (unsigned long long) measure_clock_offset() | |
1252 | ); | |
1253 | if (ret) | |
1254 | goto end; | |
1255 | ||
1256 | ret = lttng_metadata_printf(session, | |
1257 | "typealias integer {\n" | |
1258 | " size = 27; align = 1; signed = false;\n" | |
1259 | " map = clock.monotonic.value;\n" | |
1260 | "} := uint27_clock_monotonic_t;\n" | |
1261 | "\n" | |
1262 | "typealias integer {\n" | |
1263 | " size = 32; align = %u; signed = false;\n" | |
1264 | " map = clock.monotonic.value;\n" | |
1265 | "} := uint32_clock_monotonic_t;\n" | |
1266 | "\n" | |
1267 | "typealias integer {\n" | |
1268 | " size = 64; align = %u; signed = false;\n" | |
1269 | " map = clock.monotonic.value;\n" | |
1270 | "} := uint64_clock_monotonic_t;\n\n", | |
1271 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1272 | lttng_alignof(uint64_t) * CHAR_BIT | |
1273 | ); | |
1274 | if (ret) | |
1275 | goto end; | |
1276 | ||
a90917c3 | 1277 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1278 | if (ret) |
1279 | goto end; | |
1280 | ||
a90917c3 | 1281 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1282 | if (ret) |
1283 | goto end; | |
1284 | ||
c099397a MD |
1285 | skip_session: |
1286 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1287 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1288 | if (ret) |
1289 | goto end; | |
1290 | } | |
1291 | ||
1292 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1293 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1294 | if (ret) |
1295 | goto end; | |
1296 | } | |
1297 | session->metadata_dumped = 1; | |
1298 | end: | |
1299 | return ret; | |
1300 | } | |
1301 | ||
c0e31d2e | 1302 | /** |
a90917c3 | 1303 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1304 | * @transport: transport structure |
1305 | * | |
1306 | * Registers a transport which can be used as output to extract the data out of | |
1307 | * LTTng. The module calling this registration function must ensure that no | |
1308 | * trap-inducing code will be executed by the transport functions. E.g. | |
1309 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1310 | * is made visible to the transport function. This registration acts as a | |
1311 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1312 | * after its registration must it synchronize the TLBs. | |
1313 | */ | |
a90917c3 | 1314 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1315 | { |
1316 | /* | |
1317 | * Make sure no page fault can be triggered by the module about to be | |
1318 | * registered. We deal with this here so we don't have to call | |
1319 | * vmalloc_sync_all() in each module's init. | |
1320 | */ | |
6d2a620c | 1321 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1322 | |
1323 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1324 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1325 | mutex_unlock(&sessions_mutex); |
1326 | } | |
a90917c3 | 1327 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1328 | |
1329 | /** | |
a90917c3 | 1330 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1331 | * @transport: transport structure |
1332 | */ | |
a90917c3 | 1333 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1334 | { |
1335 | mutex_lock(&sessions_mutex); | |
1336 | list_del(&transport->node); | |
1337 | mutex_unlock(&sessions_mutex); | |
1338 | } | |
a90917c3 | 1339 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 1340 | |
a90917c3 | 1341 | static int __init lttng_events_init(void) |
4e3c1b9b | 1342 | { |
1c25284c MD |
1343 | int ret; |
1344 | ||
453b2495 JD |
1345 | ret = wrapper_lttng_fixup_sig(THIS_MODULE); |
1346 | if (ret) | |
1347 | return ret; | |
1348 | ||
20591cf7 MD |
1349 | ret = lttng_tracepoint_init(); |
1350 | if (ret) | |
1351 | return ret; | |
a90917c3 | 1352 | event_cache = KMEM_CACHE(lttng_event, 0); |
20591cf7 MD |
1353 | if (!event_cache) { |
1354 | ret = -ENOMEM; | |
1355 | goto error_kmem; | |
1356 | } | |
80996790 | 1357 | ret = lttng_abi_init(); |
02119ee5 MD |
1358 | if (ret) |
1359 | goto error_abi; | |
0c956676 MD |
1360 | ret = lttng_logger_init(); |
1361 | if (ret) | |
1362 | goto error_logger; | |
4e3c1b9b | 1363 | return 0; |
0c956676 MD |
1364 | |
1365 | error_logger: | |
1366 | lttng_abi_exit(); | |
02119ee5 | 1367 | error_abi: |
1c25284c | 1368 | kmem_cache_destroy(event_cache); |
20591cf7 MD |
1369 | error_kmem: |
1370 | lttng_tracepoint_exit(); | |
1c25284c | 1371 | return ret; |
4e3c1b9b MD |
1372 | } |
1373 | ||
a90917c3 | 1374 | module_init(lttng_events_init); |
11b5a3c2 | 1375 | |
a90917c3 | 1376 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 1377 | { |
a90917c3 | 1378 | struct lttng_session *session, *tmpsession; |
92e94819 | 1379 | |
0c956676 | 1380 | lttng_logger_exit(); |
80996790 | 1381 | lttng_abi_exit(); |
92e94819 | 1382 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 1383 | lttng_session_destroy(session); |
11b5a3c2 | 1384 | kmem_cache_destroy(event_cache); |
20591cf7 | 1385 | lttng_tracepoint_exit(); |
4e3c1b9b | 1386 | } |
92e94819 | 1387 | |
a90917c3 | 1388 | module_exit(lttng_events_exit); |
11b5a3c2 | 1389 | |
92e94819 MD |
1390 | MODULE_LICENSE("GPL and additional rights"); |
1391 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
1392 | MODULE_DESCRIPTION("LTTng Events"); | |
9a9973ef MD |
1393 | MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "." |
1394 | __stringify(LTTNG_MODULES_MINOR_VERSION) "." | |
309370e2 MD |
1395 | __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION) |
1396 | LTTNG_MODULES_EXTRAVERSION); |