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