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> |
a864fb02 | 30 | #include "wrapper/uuid.h" |
b13f3ebe | 31 | #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */ |
a82c63f1 | 32 | #include "wrapper/random.h" |
3a523f5b | 33 | #include "wrapper/tracepoint.h" |
9e46f0b8 | 34 | #include "lttng-kernel-version.h" |
a90917c3 MD |
35 | #include "lttng-events.h" |
36 | #include "lttng-tracer.h" | |
6dccd6c1 | 37 | #include "lttng-abi-old.h" |
4e3c1b9b MD |
38 | |
39 | static LIST_HEAD(sessions); | |
a90917c3 | 40 | static LIST_HEAD(lttng_transport_list); |
4e3c1b9b MD |
41 | static DEFINE_MUTEX(sessions_mutex); |
42 | static struct kmem_cache *event_cache; | |
43 | ||
a90917c3 MD |
44 | static void _lttng_event_destroy(struct lttng_event *event); |
45 | static void _lttng_channel_destroy(struct lttng_channel *chan); | |
46 | static int _lttng_event_unregister(struct lttng_event *event); | |
c099397a | 47 | static |
a90917c3 MD |
48 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
49 | struct lttng_channel *chan, | |
50 | struct lttng_event *event); | |
c099397a | 51 | static |
a90917c3 | 52 | int _lttng_session_metadata_statedump(struct lttng_session *session); |
c099397a | 53 | |
c099397a | 54 | void synchronize_trace(void) |
abcca994 MD |
55 | { |
56 | synchronize_sched(); | |
9e46f0b8 MD |
57 | #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) |
58 | #ifdef CONFIG_PREEMPT_RT_FULL | |
59 | synchronize_rcu(); | |
60 | #endif | |
61 | #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ | |
abcca994 MD |
62 | #ifdef CONFIG_PREEMPT_RT |
63 | synchronize_rcu(); | |
64 | #endif | |
9e46f0b8 | 65 | #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */ |
abcca994 MD |
66 | } |
67 | ||
a90917c3 | 68 | struct lttng_session *lttng_session_create(void) |
4e3c1b9b | 69 | { |
a90917c3 | 70 | struct lttng_session *session; |
4e3c1b9b MD |
71 | |
72 | mutex_lock(&sessions_mutex); | |
a90917c3 | 73 | session = kzalloc(sizeof(struct lttng_session), GFP_KERNEL); |
4e3c1b9b MD |
74 | if (!session) |
75 | return NULL; | |
4e3c1b9b | 76 | INIT_LIST_HEAD(&session->chan); |
f3d01b96 | 77 | INIT_LIST_HEAD(&session->events); |
d793d5e1 | 78 | uuid_le_gen(&session->uuid); |
4e3c1b9b MD |
79 | list_add(&session->list, &sessions); |
80 | mutex_unlock(&sessions_mutex); | |
81 | return session; | |
4e3c1b9b MD |
82 | } |
83 | ||
a90917c3 | 84 | void lttng_session_destroy(struct lttng_session *session) |
4e3c1b9b | 85 | { |
a90917c3 MD |
86 | struct lttng_channel *chan, *tmpchan; |
87 | struct lttng_event *event, *tmpevent; | |
dda6a249 | 88 | int ret; |
4e3c1b9b MD |
89 | |
90 | mutex_lock(&sessions_mutex); | |
52fc2e1f | 91 | ACCESS_ONCE(session->active) = 0; |
1ec65de1 MD |
92 | list_for_each_entry(chan, &session->chan, list) { |
93 | ret = lttng_syscalls_unregister(chan); | |
94 | WARN_ON(ret); | |
95 | } | |
dda6a249 | 96 | list_for_each_entry(event, &session->events, list) { |
a90917c3 | 97 | ret = _lttng_event_unregister(event); |
dda6a249 MD |
98 | WARN_ON(ret); |
99 | } | |
abcca994 | 100 | synchronize_trace(); /* Wait for in-flight events to complete */ |
4e3c1b9b | 101 | list_for_each_entry_safe(event, tmpevent, &session->events, list) |
a90917c3 | 102 | _lttng_event_destroy(event); |
4e3c1b9b | 103 | list_for_each_entry_safe(chan, tmpchan, &session->chan, list) |
a90917c3 | 104 | _lttng_channel_destroy(chan); |
4e3c1b9b MD |
105 | list_del(&session->list); |
106 | mutex_unlock(&sessions_mutex); | |
107 | kfree(session); | |
108 | } | |
109 | ||
a90917c3 | 110 | int lttng_session_enable(struct lttng_session *session) |
c0e31d2e MD |
111 | { |
112 | int ret = 0; | |
a90917c3 | 113 | struct lttng_channel *chan; |
c0e31d2e MD |
114 | |
115 | mutex_lock(&sessions_mutex); | |
116 | if (session->active) { | |
117 | ret = -EBUSY; | |
118 | goto end; | |
119 | } | |
c099397a MD |
120 | |
121 | /* | |
122 | * Snapshot the number of events per channel to know the type of header | |
123 | * we need to use. | |
124 | */ | |
125 | list_for_each_entry(chan, &session->chan, list) { | |
126 | if (chan->header_type) | |
127 | continue; /* don't change it if session stop/restart */ | |
128 | if (chan->free_event_id < 31) | |
129 | chan->header_type = 1; /* compact */ | |
130 | else | |
131 | chan->header_type = 2; /* large */ | |
132 | } | |
133 | ||
52fc2e1f | 134 | ACCESS_ONCE(session->active) = 1; |
8070f5c0 | 135 | ACCESS_ONCE(session->been_active) = 1; |
a90917c3 | 136 | ret = _lttng_session_metadata_statedump(session); |
c337ddc2 MD |
137 | if (ret) { |
138 | ACCESS_ONCE(session->active) = 0; | |
139 | goto end; | |
140 | } | |
141 | ret = lttng_statedump_start(session); | |
360f38ea | 142 | if (ret) |
c099397a | 143 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
144 | end: |
145 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 146 | return ret; |
c0e31d2e MD |
147 | } |
148 | ||
a90917c3 | 149 | int lttng_session_disable(struct lttng_session *session) |
c0e31d2e MD |
150 | { |
151 | int ret = 0; | |
152 | ||
153 | mutex_lock(&sessions_mutex); | |
154 | if (!session->active) { | |
155 | ret = -EBUSY; | |
156 | goto end; | |
157 | } | |
52fc2e1f | 158 | ACCESS_ONCE(session->active) = 0; |
c0e31d2e MD |
159 | end: |
160 | mutex_unlock(&sessions_mutex); | |
11b5a3c2 | 161 | return ret; |
c0e31d2e MD |
162 | } |
163 | ||
a90917c3 | 164 | int lttng_channel_enable(struct lttng_channel *channel) |
e64957da MD |
165 | { |
166 | int old; | |
167 | ||
c6485006 MD |
168 | if (channel == channel->session->metadata) |
169 | return -EPERM; | |
e64957da MD |
170 | old = xchg(&channel->enabled, 1); |
171 | if (old) | |
172 | return -EEXIST; | |
173 | return 0; | |
174 | } | |
175 | ||
a90917c3 | 176 | int lttng_channel_disable(struct lttng_channel *channel) |
e64957da MD |
177 | { |
178 | int old; | |
179 | ||
c6485006 MD |
180 | if (channel == channel->session->metadata) |
181 | return -EPERM; | |
e64957da MD |
182 | old = xchg(&channel->enabled, 0); |
183 | if (!old) | |
184 | return -EEXIST; | |
185 | return 0; | |
186 | } | |
187 | ||
a90917c3 | 188 | int lttng_event_enable(struct lttng_event *event) |
e64957da MD |
189 | { |
190 | int old; | |
191 | ||
c6485006 MD |
192 | if (event->chan == event->chan->session->metadata) |
193 | return -EPERM; | |
e64957da MD |
194 | old = xchg(&event->enabled, 1); |
195 | if (old) | |
196 | return -EEXIST; | |
197 | return 0; | |
198 | } | |
199 | ||
a90917c3 | 200 | int lttng_event_disable(struct lttng_event *event) |
e64957da MD |
201 | { |
202 | int old; | |
203 | ||
c6485006 MD |
204 | if (event->chan == event->chan->session->metadata) |
205 | return -EPERM; | |
e64957da MD |
206 | old = xchg(&event->enabled, 0); |
207 | if (!old) | |
208 | return -EEXIST; | |
209 | return 0; | |
210 | } | |
211 | ||
a90917c3 | 212 | static struct lttng_transport *lttng_transport_find(const char *name) |
f3d01b96 | 213 | { |
a90917c3 | 214 | struct lttng_transport *transport; |
f3d01b96 | 215 | |
a90917c3 | 216 | list_for_each_entry(transport, <tng_transport_list, node) { |
f3d01b96 MD |
217 | if (!strcmp(transport->name, name)) |
218 | return transport; | |
219 | } | |
220 | return NULL; | |
221 | } | |
222 | ||
a90917c3 | 223 | struct lttng_channel *lttng_channel_create(struct lttng_session *session, |
5dbbdb43 MD |
224 | const char *transport_name, |
225 | void *buf_addr, | |
4e3c1b9b MD |
226 | size_t subbuf_size, size_t num_subbuf, |
227 | unsigned int switch_timer_interval, | |
228 | unsigned int read_timer_interval) | |
229 | { | |
a90917c3 MD |
230 | struct lttng_channel *chan; |
231 | struct lttng_transport *transport = NULL; | |
4e3c1b9b MD |
232 | |
233 | mutex_lock(&sessions_mutex); | |
8070f5c0 | 234 | if (session->been_active) |
e5382b6d | 235 | goto active; /* Refuse to add channel to active session */ |
a90917c3 | 236 | transport = lttng_transport_find(transport_name); |
f3d01b96 MD |
237 | if (!transport) { |
238 | printk(KERN_WARNING "LTTng transport %s not found\n", | |
239 | transport_name); | |
c0e31d2e | 240 | goto notransport; |
f3d01b96 | 241 | } |
a33c9927 MD |
242 | if (!try_module_get(transport->owner)) { |
243 | printk(KERN_WARNING "LTT : Can't lock transport module.\n"); | |
244 | goto notransport; | |
245 | } | |
a90917c3 | 246 | chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL); |
4e3c1b9b | 247 | if (!chan) |
c0e31d2e | 248 | goto nomem; |
4e3c1b9b | 249 | chan->session = session; |
05d32c64 | 250 | chan->id = session->free_chan_id++; |
125b4df4 MD |
251 | /* |
252 | * Note: the channel creation op already writes into the packet | |
253 | * headers. Therefore the "chan" information used as input | |
254 | * should be already accessible. | |
255 | */ | |
5f5ddf01 MD |
256 | chan->chan = transport->ops.channel_create(transport_name, |
257 | chan, buf_addr, subbuf_size, num_subbuf, | |
258 | switch_timer_interval, read_timer_interval); | |
f3d01b96 MD |
259 | if (!chan->chan) |
260 | goto create_error; | |
e64957da | 261 | chan->enabled = 1; |
11b5a3c2 | 262 | chan->ops = &transport->ops; |
a33c9927 | 263 | chan->transport = transport; |
4e3c1b9b MD |
264 | list_add(&chan->list, &session->chan); |
265 | mutex_unlock(&sessions_mutex); | |
266 | return chan; | |
267 | ||
f3d01b96 MD |
268 | create_error: |
269 | kfree(chan); | |
c0e31d2e | 270 | nomem: |
a33c9927 MD |
271 | if (transport) |
272 | module_put(transport->owner); | |
c0e31d2e | 273 | notransport: |
e5382b6d | 274 | active: |
4e3c1b9b MD |
275 | mutex_unlock(&sessions_mutex); |
276 | return NULL; | |
277 | } | |
278 | ||
279 | /* | |
280 | * Only used internally at session destruction. | |
281 | */ | |
aa7c23a9 | 282 | static |
a90917c3 | 283 | void _lttng_channel_destroy(struct lttng_channel *chan) |
4e3c1b9b | 284 | { |
11b5a3c2 | 285 | chan->ops->channel_destroy(chan->chan); |
a33c9927 | 286 | module_put(chan->transport->owner); |
4e3c1b9b | 287 | list_del(&chan->list); |
8070f5c0 | 288 | lttng_destroy_context(chan->ctx); |
4e3c1b9b MD |
289 | kfree(chan); |
290 | } | |
291 | ||
e5382b6d MD |
292 | /* |
293 | * Supports event creation while tracing session is active. | |
294 | */ | |
a90917c3 | 295 | struct lttng_event *lttng_event_create(struct lttng_channel *chan, |
d6d808f3 | 296 | struct lttng_kernel_event *event_param, |
259b6cb3 MD |
297 | void *filter, |
298 | const struct lttng_event_desc *internal_desc) | |
4e3c1b9b | 299 | { |
a90917c3 | 300 | struct lttng_event *event; |
3d084699 | 301 | int ret; |
4e3c1b9b MD |
302 | |
303 | mutex_lock(&sessions_mutex); | |
37303c75 | 304 | if (chan->free_event_id == -1U) |
e5382b6d | 305 | goto full; |
4e3c1b9b | 306 | /* |
dda6a249 MD |
307 | * This is O(n^2) (for each event, the loop is called at event |
308 | * creation). Might require a hash if we have lots of events. | |
4e3c1b9b MD |
309 | */ |
310 | list_for_each_entry(event, &chan->session->events, list) | |
30bdb6e4 | 311 | if (!strcmp(event->desc->name, event_param->name)) |
4e3c1b9b | 312 | goto exist; |
11b5a3c2 | 313 | event = kmem_cache_zalloc(event_cache, GFP_KERNEL); |
4e3c1b9b MD |
314 | if (!event) |
315 | goto cache_error; | |
4e3c1b9b MD |
316 | event->chan = chan; |
317 | event->filter = filter; | |
e5382b6d | 318 | event->id = chan->free_event_id++; |
e64957da | 319 | event->enabled = 1; |
d6d808f3 | 320 | event->instrumentation = event_param->instrumentation; |
a90917c3 | 321 | /* Populate lttng_event structure before tracepoint registration. */ |
e5382b6d | 322 | smp_wmb(); |
d6d808f3 | 323 | switch (event_param->instrumentation) { |
ab2277d6 | 324 | case LTTNG_KERNEL_TRACEPOINT: |
a90917c3 | 325 | event->desc = lttng_event_get(event_param->name); |
d3dbe23c MD |
326 | if (!event->desc) |
327 | goto register_error; | |
3a523f5b | 328 | ret = kabi_2635_tracepoint_probe_register(event_param->name, |
d3dbe23c MD |
329 | event->desc->probe_callback, |
330 | event); | |
11b5a3c2 MD |
331 | if (ret) |
332 | goto register_error; | |
baf20995 | 333 | break; |
ab2277d6 | 334 | case LTTNG_KERNEL_KPROBE: |
30bdb6e4 | 335 | ret = lttng_kprobes_register(event_param->name, |
f17701fb MD |
336 | event_param->u.kprobe.symbol_name, |
337 | event_param->u.kprobe.offset, | |
338 | event_param->u.kprobe.addr, | |
339 | event); | |
340 | if (ret) | |
d6d808f3 | 341 | goto register_error; |
edeb3137 MD |
342 | ret = try_module_get(event->desc->owner); |
343 | WARN_ON_ONCE(!ret); | |
d6d808f3 | 344 | break; |
7371f44c MD |
345 | case LTTNG_KERNEL_KRETPROBE: |
346 | { | |
a90917c3 | 347 | struct lttng_event *event_return; |
7371f44c MD |
348 | |
349 | /* kretprobe defines 2 events */ | |
350 | event_return = | |
351 | kmem_cache_zalloc(event_cache, GFP_KERNEL); | |
352 | if (!event_return) | |
353 | goto register_error; | |
354 | event_return->chan = chan; | |
355 | event_return->filter = filter; | |
356 | event_return->id = chan->free_event_id++; | |
357 | event_return->enabled = 1; | |
358 | event_return->instrumentation = event_param->instrumentation; | |
359 | /* | |
a90917c3 | 360 | * Populate lttng_event structure before kretprobe registration. |
7371f44c MD |
361 | */ |
362 | smp_wmb(); | |
363 | ret = lttng_kretprobes_register(event_param->name, | |
364 | event_param->u.kretprobe.symbol_name, | |
365 | event_param->u.kretprobe.offset, | |
366 | event_param->u.kretprobe.addr, | |
367 | event, event_return); | |
368 | if (ret) { | |
369 | kmem_cache_free(event_cache, event_return); | |
370 | goto register_error; | |
371 | } | |
372 | /* Take 2 refs on the module: one per event. */ | |
373 | ret = try_module_get(event->desc->owner); | |
374 | WARN_ON_ONCE(!ret); | |
375 | ret = try_module_get(event->desc->owner); | |
376 | WARN_ON_ONCE(!ret); | |
a90917c3 | 377 | ret = _lttng_event_metadata_statedump(chan->session, chan, |
7371f44c MD |
378 | event_return); |
379 | if (ret) { | |
380 | kmem_cache_free(event_cache, event_return); | |
381 | module_put(event->desc->owner); | |
382 | module_put(event->desc->owner); | |
383 | goto statedump_error; | |
384 | } | |
385 | list_add(&event_return->list, &chan->session->events); | |
386 | break; | |
387 | } | |
ab2277d6 | 388 | case LTTNG_KERNEL_FUNCTION: |
30bdb6e4 | 389 | ret = lttng_ftrace_register(event_param->name, |
e0a7a7c4 MD |
390 | event_param->u.ftrace.symbol_name, |
391 | event); | |
392 | if (ret) | |
393 | goto register_error; | |
edeb3137 MD |
394 | ret = try_module_get(event->desc->owner); |
395 | WARN_ON_ONCE(!ret); | |
e0a7a7c4 | 396 | break; |
1ec65de1 | 397 | case LTTNG_KERNEL_NOOP: |
259b6cb3 MD |
398 | event->desc = internal_desc; |
399 | if (!event->desc) | |
400 | goto register_error; | |
1ec65de1 | 401 | break; |
baf20995 MD |
402 | default: |
403 | WARN_ON_ONCE(1); | |
404 | } | |
a90917c3 | 405 | ret = _lttng_event_metadata_statedump(chan->session, chan, event); |
c099397a MD |
406 | if (ret) |
407 | goto statedump_error; | |
dda6a249 | 408 | list_add(&event->list, &chan->session->events); |
11b5a3c2 | 409 | mutex_unlock(&sessions_mutex); |
4e3c1b9b MD |
410 | return event; |
411 | ||
c099397a | 412 | statedump_error: |
259b6cb3 | 413 | /* If a statedump error occurs, events will not be readable. */ |
11b5a3c2 | 414 | register_error: |
11b5a3c2 | 415 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
416 | cache_error: |
417 | exist: | |
e5382b6d | 418 | full: |
4e3c1b9b MD |
419 | mutex_unlock(&sessions_mutex); |
420 | return NULL; | |
421 | } | |
422 | ||
423 | /* | |
424 | * Only used internally at session destruction. | |
425 | */ | |
a90917c3 | 426 | int _lttng_event_unregister(struct lttng_event *event) |
4e3c1b9b | 427 | { |
11b5a3c2 MD |
428 | int ret = -EINVAL; |
429 | ||
38d024ae | 430 | switch (event->instrumentation) { |
ab2277d6 | 431 | case LTTNG_KERNEL_TRACEPOINT: |
3a523f5b | 432 | ret = kabi_2635_tracepoint_probe_unregister(event->desc->name, |
85a9ca7f | 433 | event->desc->probe_callback, |
11b5a3c2 MD |
434 | event); |
435 | if (ret) | |
436 | return ret; | |
baf20995 | 437 | break; |
ab2277d6 | 438 | case LTTNG_KERNEL_KPROBE: |
f17701fb | 439 | lttng_kprobes_unregister(event); |
d6d808f3 MD |
440 | ret = 0; |
441 | break; | |
7371f44c MD |
442 | case LTTNG_KERNEL_KRETPROBE: |
443 | lttng_kretprobes_unregister(event); | |
444 | ret = 0; | |
445 | break; | |
ab2277d6 | 446 | case LTTNG_KERNEL_FUNCTION: |
e0a7a7c4 MD |
447 | lttng_ftrace_unregister(event); |
448 | ret = 0; | |
449 | break; | |
259b6cb3 MD |
450 | case LTTNG_KERNEL_NOOP: |
451 | ret = 0; | |
452 | break; | |
baf20995 MD |
453 | default: |
454 | WARN_ON_ONCE(1); | |
455 | } | |
dda6a249 MD |
456 | return ret; |
457 | } | |
458 | ||
459 | /* | |
460 | * Only used internally at session destruction. | |
461 | */ | |
be066e6c | 462 | static |
a90917c3 | 463 | void _lttng_event_destroy(struct lttng_event *event) |
dda6a249 | 464 | { |
edeb3137 MD |
465 | switch (event->instrumentation) { |
466 | case LTTNG_KERNEL_TRACEPOINT: | |
a90917c3 | 467 | lttng_event_put(event->desc); |
edeb3137 MD |
468 | break; |
469 | case LTTNG_KERNEL_KPROBE: | |
470 | module_put(event->desc->owner); | |
471 | lttng_kprobes_destroy_private(event); | |
472 | break; | |
7371f44c MD |
473 | case LTTNG_KERNEL_KRETPROBE: |
474 | module_put(event->desc->owner); | |
475 | lttng_kretprobes_destroy_private(event); | |
476 | break; | |
edeb3137 MD |
477 | case LTTNG_KERNEL_FUNCTION: |
478 | module_put(event->desc->owner); | |
479 | lttng_ftrace_destroy_private(event); | |
480 | break; | |
259b6cb3 MD |
481 | case LTTNG_KERNEL_NOOP: |
482 | break; | |
edeb3137 MD |
483 | default: |
484 | WARN_ON_ONCE(1); | |
485 | } | |
dda6a249 | 486 | list_del(&event->list); |
8070f5c0 | 487 | lttng_destroy_context(event->ctx); |
11b5a3c2 | 488 | kmem_cache_free(event_cache, event); |
4e3c1b9b MD |
489 | } |
490 | ||
1ec3f75a MD |
491 | /* |
492 | * We have exclusive access to our metadata buffer (protected by the | |
493 | * sessions_mutex), so we can do racy operations such as looking for | |
494 | * remaining space left in packet and write, since mutual exclusion | |
495 | * protects us from concurrent writes. | |
496 | */ | |
a90917c3 | 497 | int lttng_metadata_printf(struct lttng_session *session, |
c099397a MD |
498 | const char *fmt, ...) |
499 | { | |
500 | struct lib_ring_buffer_ctx ctx; | |
a90917c3 | 501 | struct lttng_channel *chan = session->metadata; |
c099397a MD |
502 | char *str; |
503 | int ret = 0, waitret; | |
1ec3f75a | 504 | size_t len, reserve_len, pos; |
c099397a MD |
505 | va_list ap; |
506 | ||
507 | WARN_ON_ONCE(!ACCESS_ONCE(session->active)); | |
508 | ||
509 | va_start(ap, fmt); | |
510 | str = kvasprintf(GFP_KERNEL, fmt, ap); | |
511 | va_end(ap); | |
512 | if (!str) | |
513 | return -ENOMEM; | |
514 | ||
1ec3f75a MD |
515 | len = strlen(str); |
516 | pos = 0; | |
517 | ||
518 | for (pos = 0; pos < len; pos += reserve_len) { | |
519 | reserve_len = min_t(size_t, | |
520 | chan->ops->packet_avail_size(chan->chan), | |
521 | len - pos); | |
522 | lib_ring_buffer_ctx_init(&ctx, chan->chan, NULL, reserve_len, | |
523 | sizeof(char), -1); | |
524 | /* | |
525 | * We don't care about metadata buffer's records lost | |
526 | * count, because we always retry here. Report error if | |
527 | * we need to bail out after timeout or being | |
528 | * interrupted. | |
529 | */ | |
71c1d843 | 530 | waitret = wait_event_interruptible_timeout(*chan->ops->get_writer_buf_wait_queue(chan->chan, -1), |
1ec3f75a | 531 | ({ |
4e1f08f4 | 532 | ret = chan->ops->event_reserve(&ctx, 0); |
1ec3f75a MD |
533 | ret != -ENOBUFS || !ret; |
534 | }), | |
535 | msecs_to_jiffies(LTTNG_METADATA_TIMEOUT_MSEC)); | |
536 | if (!waitret || waitret == -ERESTARTSYS || ret) { | |
537 | printk(KERN_WARNING "LTTng: Failure to write metadata to buffers (%s)\n", | |
538 | waitret == -ERESTARTSYS ? "interrupted" : | |
539 | (ret == -ENOBUFS ? "timeout" : "I/O error")); | |
540 | if (waitret == -ERESTARTSYS) | |
541 | ret = waitret; | |
542 | goto end; | |
543 | } | |
f5cf8eff | 544 | chan->ops->event_write(&ctx, &str[pos], reserve_len); |
1ec3f75a | 545 | chan->ops->event_commit(&ctx); |
c099397a | 546 | } |
c099397a MD |
547 | end: |
548 | kfree(str); | |
549 | return ret; | |
550 | } | |
551 | ||
552 | static | |
a90917c3 | 553 | int _lttng_field_statedump(struct lttng_session *session, |
8070f5c0 | 554 | const struct lttng_event_field *field) |
c099397a | 555 | { |
c099397a | 556 | int ret = 0; |
c099397a | 557 | |
8070f5c0 MD |
558 | switch (field->type.atype) { |
559 | case atype_integer: | |
560 | ret = lttng_metadata_printf(session, | |
244465ab | 561 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n", |
8070f5c0 MD |
562 | field->type.u.basic.integer.size, |
563 | field->type.u.basic.integer.alignment, | |
564 | field->type.u.basic.integer.signedness, | |
565 | (field->type.u.basic.integer.encoding == lttng_encode_none) | |
566 | ? "none" | |
567 | : (field->type.u.basic.integer.encoding == lttng_encode_UTF8) | |
568 | ? "UTF8" | |
569 | : "ASCII", | |
570 | field->type.u.basic.integer.base, | |
c099397a | 571 | #ifdef __BIG_ENDIAN |
8070f5c0 | 572 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
c099397a | 573 | #else |
8070f5c0 | 574 | field->type.u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
c099397a | 575 | #endif |
8070f5c0 MD |
576 | field->name); |
577 | break; | |
578 | case atype_enum: | |
579 | ret = lttng_metadata_printf(session, | |
244465ab | 580 | " %s _%s;\n", |
8070f5c0 MD |
581 | field->type.u.basic.enumeration.name, |
582 | field->name); | |
583 | break; | |
584 | case atype_array: | |
585 | { | |
586 | const struct lttng_basic_type *elem_type; | |
587 | ||
588 | elem_type = &field->type.u.array.elem_type; | |
589 | ret = lttng_metadata_printf(session, | |
244465ab | 590 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n", |
8070f5c0 MD |
591 | elem_type->u.basic.integer.size, |
592 | elem_type->u.basic.integer.alignment, | |
593 | elem_type->u.basic.integer.signedness, | |
594 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
595 | ? "none" | |
596 | : (elem_type->u.basic.integer.encoding == lttng_encode_UTF8) | |
597 | ? "UTF8" | |
598 | : "ASCII", | |
599 | elem_type->u.basic.integer.base, | |
8fa75f34 | 600 | #ifdef __BIG_ENDIAN |
8070f5c0 | 601 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 602 | #else |
8070f5c0 | 603 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 604 | #endif |
8070f5c0 MD |
605 | field->name, field->type.u.array.length); |
606 | break; | |
607 | } | |
608 | case atype_sequence: | |
609 | { | |
610 | const struct lttng_basic_type *elem_type; | |
611 | const struct lttng_basic_type *length_type; | |
612 | ||
613 | elem_type = &field->type.u.sequence.elem_type; | |
614 | length_type = &field->type.u.sequence.length_type; | |
615 | ret = lttng_metadata_printf(session, | |
616 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n", | |
8070f5c0 | 617 | length_type->u.basic.integer.size, |
32257272 | 618 | (unsigned int) length_type->u.basic.integer.alignment, |
8070f5c0 MD |
619 | length_type->u.basic.integer.signedness, |
620 | (length_type->u.basic.integer.encoding == lttng_encode_none) | |
621 | ? "none" | |
0635cdd4 | 622 | : ((length_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 623 | ? "UTF8" |
0635cdd4 | 624 | : "ASCII"), |
8070f5c0 | 625 | length_type->u.basic.integer.base, |
e0a7a7c4 | 626 | #ifdef __BIG_ENDIAN |
8070f5c0 | 627 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
e0a7a7c4 | 628 | #else |
0635cdd4 | 629 | length_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
e0a7a7c4 | 630 | #endif |
27d2368e MD |
631 | field->name); |
632 | if (ret) | |
633 | return ret; | |
634 | ||
635 | ret = lttng_metadata_printf(session, | |
244465ab | 636 | " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n", |
8070f5c0 | 637 | elem_type->u.basic.integer.size, |
32257272 | 638 | (unsigned int) elem_type->u.basic.integer.alignment, |
8070f5c0 MD |
639 | elem_type->u.basic.integer.signedness, |
640 | (elem_type->u.basic.integer.encoding == lttng_encode_none) | |
641 | ? "none" | |
0635cdd4 | 642 | : ((elem_type->u.basic.integer.encoding == lttng_encode_UTF8) |
8070f5c0 | 643 | ? "UTF8" |
0635cdd4 | 644 | : "ASCII"), |
8070f5c0 | 645 | elem_type->u.basic.integer.base, |
8fa75f34 | 646 | #ifdef __BIG_ENDIAN |
8070f5c0 | 647 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = le;" : "", |
8fa75f34 | 648 | #else |
8070f5c0 | 649 | elem_type->u.basic.integer.reverse_byte_order ? " byte_order = be;" : "", |
8fa75f34 | 650 | #endif |
8070f5c0 | 651 | field->name, |
27d2368e | 652 | field->name); |
8070f5c0 MD |
653 | break; |
654 | } | |
c099397a | 655 | |
8070f5c0 MD |
656 | case atype_string: |
657 | /* Default encoding is UTF8 */ | |
658 | ret = lttng_metadata_printf(session, | |
244465ab | 659 | " string%s _%s;\n", |
8070f5c0 MD |
660 | field->type.u.basic.string.encoding == lttng_encode_ASCII ? |
661 | " { encoding = ASCII; }" : "", | |
662 | field->name); | |
663 | break; | |
664 | default: | |
665 | WARN_ON_ONCE(1); | |
666 | return -EINVAL; | |
667 | } | |
668 | return ret; | |
669 | } | |
670 | ||
671 | static | |
a90917c3 | 672 | int _lttng_context_metadata_statedump(struct lttng_session *session, |
8070f5c0 MD |
673 | struct lttng_ctx *ctx) |
674 | { | |
675 | int ret = 0; | |
676 | int i; | |
677 | ||
678 | if (!ctx) | |
679 | return 0; | |
680 | for (i = 0; i < ctx->nr_fields; i++) { | |
681 | const struct lttng_ctx_field *field = &ctx->fields[i]; | |
682 | ||
a90917c3 | 683 | ret = _lttng_field_statedump(session, &field->event_field); |
8070f5c0 MD |
684 | if (ret) |
685 | return ret; | |
686 | } | |
687 | return ret; | |
688 | } | |
689 | ||
690 | static | |
a90917c3 MD |
691 | int _lttng_fields_metadata_statedump(struct lttng_session *session, |
692 | struct lttng_event *event) | |
8070f5c0 MD |
693 | { |
694 | const struct lttng_event_desc *desc = event->desc; | |
695 | int ret = 0; | |
696 | int i; | |
697 | ||
698 | for (i = 0; i < desc->nr_fields; i++) { | |
699 | const struct lttng_event_field *field = &desc->fields[i]; | |
700 | ||
a90917c3 | 701 | ret = _lttng_field_statedump(session, field); |
8070f5c0 MD |
702 | if (ret) |
703 | return ret; | |
c099397a MD |
704 | } |
705 | return ret; | |
706 | } | |
707 | ||
708 | static | |
a90917c3 MD |
709 | int _lttng_event_metadata_statedump(struct lttng_session *session, |
710 | struct lttng_channel *chan, | |
711 | struct lttng_event *event) | |
c099397a MD |
712 | { |
713 | int ret = 0; | |
714 | ||
715 | if (event->metadata_dumped || !ACCESS_ONCE(session->active)) | |
716 | return 0; | |
717 | if (chan == session->metadata) | |
718 | return 0; | |
719 | ||
720 | ret = lttng_metadata_printf(session, | |
721 | "event {\n" | |
722 | " name = %s;\n" | |
723 | " id = %u;\n" | |
b9074a1b | 724 | " stream_id = %u;\n", |
c099397a MD |
725 | event->desc->name, |
726 | event->id, | |
727 | event->chan->id); | |
728 | if (ret) | |
729 | goto end; | |
730 | ||
b9074a1b MD |
731 | if (event->ctx) { |
732 | ret = lttng_metadata_printf(session, | |
733 | " context := struct {\n"); | |
734 | if (ret) | |
735 | goto end; | |
736 | } | |
a90917c3 | 737 | ret = _lttng_context_metadata_statedump(session, event->ctx); |
8070f5c0 MD |
738 | if (ret) |
739 | goto end; | |
b9074a1b MD |
740 | if (event->ctx) { |
741 | ret = lttng_metadata_printf(session, | |
742 | " };\n"); | |
743 | if (ret) | |
744 | goto end; | |
745 | } | |
8070f5c0 MD |
746 | |
747 | ret = lttng_metadata_printf(session, | |
8070f5c0 MD |
748 | " fields := struct {\n" |
749 | ); | |
750 | if (ret) | |
751 | goto end; | |
752 | ||
a90917c3 | 753 | ret = _lttng_fields_metadata_statedump(session, event); |
c099397a MD |
754 | if (ret) |
755 | goto end; | |
756 | ||
757 | /* | |
758 | * LTTng space reservation can only reserve multiples of the | |
759 | * byte size. | |
760 | */ | |
761 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
762 | " };\n" |
763 | "};\n\n"); | |
c099397a MD |
764 | if (ret) |
765 | goto end; | |
766 | ||
c099397a MD |
767 | event->metadata_dumped = 1; |
768 | end: | |
769 | return ret; | |
770 | ||
771 | } | |
772 | ||
773 | static | |
a90917c3 MD |
774 | int _lttng_channel_metadata_statedump(struct lttng_session *session, |
775 | struct lttng_channel *chan) | |
c099397a MD |
776 | { |
777 | int ret = 0; | |
778 | ||
779 | if (chan->metadata_dumped || !ACCESS_ONCE(session->active)) | |
780 | return 0; | |
781 | if (chan == session->metadata) | |
782 | return 0; | |
783 | ||
784 | WARN_ON_ONCE(!chan->header_type); | |
785 | ret = lttng_metadata_printf(session, | |
786 | "stream {\n" | |
787 | " id = %u;\n" | |
9115fbdc | 788 | " event.header := %s;\n" |
b9074a1b | 789 | " packet.context := struct packet_context;\n", |
c099397a MD |
790 | chan->id, |
791 | chan->header_type == 1 ? "struct event_header_compact" : | |
792 | "struct event_header_large"); | |
793 | if (ret) | |
794 | goto end; | |
795 | ||
b9074a1b MD |
796 | if (chan->ctx) { |
797 | ret = lttng_metadata_printf(session, | |
798 | " event.context := struct {\n"); | |
799 | if (ret) | |
800 | goto end; | |
801 | } | |
a90917c3 | 802 | ret = _lttng_context_metadata_statedump(session, chan->ctx); |
8070f5c0 MD |
803 | if (ret) |
804 | goto end; | |
b9074a1b MD |
805 | if (chan->ctx) { |
806 | ret = lttng_metadata_printf(session, | |
807 | " };\n"); | |
808 | if (ret) | |
809 | goto end; | |
810 | } | |
8070f5c0 MD |
811 | |
812 | ret = lttng_metadata_printf(session, | |
b9074a1b | 813 | "};\n\n"); |
8070f5c0 | 814 | |
c099397a MD |
815 | chan->metadata_dumped = 1; |
816 | end: | |
817 | return ret; | |
818 | } | |
819 | ||
9115fbdc | 820 | static |
a90917c3 | 821 | int _lttng_stream_packet_context_declare(struct lttng_session *session) |
9115fbdc MD |
822 | { |
823 | return lttng_metadata_printf(session, | |
824 | "struct packet_context {\n" | |
a3ccff4f MD |
825 | " uint64_clock_monotonic_t timestamp_begin;\n" |
826 | " uint64_clock_monotonic_t timestamp_end;\n" | |
576ca06a MD |
827 | " uint64_t content_size;\n" |
828 | " uint64_t packet_size;\n" | |
a9afe705 | 829 | " unsigned long events_discarded;\n" |
9115fbdc | 830 | " uint32_t cpu_id;\n" |
c6dfdf6f | 831 | "};\n\n" |
9115fbdc MD |
832 | ); |
833 | } | |
834 | ||
835 | /* | |
836 | * Compact header: | |
837 | * id: range: 0 - 30. | |
838 | * id 31 is reserved to indicate an extended header. | |
839 | * | |
840 | * Large header: | |
841 | * id: range: 0 - 65534. | |
842 | * id 65535 is reserved to indicate an extended header. | |
843 | */ | |
844 | static | |
a90917c3 | 845 | int _lttng_event_header_declare(struct lttng_session *session) |
9115fbdc MD |
846 | { |
847 | return lttng_metadata_printf(session, | |
848 | "struct event_header_compact {\n" | |
849 | " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n" | |
850 | " variant <id> {\n" | |
851 | " struct {\n" | |
a3ccff4f | 852 | " uint27_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
853 | " } compact;\n" |
854 | " struct {\n" | |
855 | " uint32_t id;\n" | |
a3ccff4f | 856 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
857 | " } extended;\n" |
858 | " } v;\n" | |
859 | "} align(%u);\n" | |
860 | "\n" | |
861 | "struct event_header_large {\n" | |
862 | " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n" | |
863 | " variant <id> {\n" | |
864 | " struct {\n" | |
a3ccff4f | 865 | " uint32_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
866 | " } compact;\n" |
867 | " struct {\n" | |
868 | " uint32_t id;\n" | |
a3ccff4f | 869 | " uint64_clock_monotonic_t timestamp;\n" |
9115fbdc MD |
870 | " } extended;\n" |
871 | " } v;\n" | |
872 | "} align(%u);\n\n", | |
a90917c3 MD |
873 | lttng_alignof(uint32_t) * CHAR_BIT, |
874 | lttng_alignof(uint16_t) * CHAR_BIT | |
9115fbdc MD |
875 | ); |
876 | } | |
877 | ||
a3ccff4f MD |
878 | /* |
879 | * Approximation of NTP time of day to clock monotonic correlation, | |
880 | * taken at start of trace. | |
881 | * Yes, this is only an approximation. Yes, we can (and will) do better | |
882 | * in future versions. | |
883 | */ | |
884 | static | |
885 | uint64_t measure_clock_offset(void) | |
886 | { | |
887 | uint64_t offset, monotonic[2], realtime; | |
888 | struct timespec rts = { 0, 0 }; | |
889 | unsigned long flags; | |
890 | ||
891 | /* Disable interrupts to increase correlation precision. */ | |
892 | local_irq_save(flags); | |
893 | monotonic[0] = trace_clock_read64(); | |
894 | getnstimeofday(&rts); | |
895 | monotonic[1] = trace_clock_read64(); | |
896 | local_irq_restore(flags); | |
897 | ||
898 | offset = (monotonic[0] + monotonic[1]) >> 1; | |
57be518d | 899 | realtime = (uint64_t) rts.tv_sec * NSEC_PER_SEC; |
a3ccff4f MD |
900 | realtime += rts.tv_nsec; |
901 | offset = realtime - offset; | |
902 | return offset; | |
903 | } | |
904 | ||
c099397a MD |
905 | /* |
906 | * Output metadata into this session's metadata buffers. | |
907 | */ | |
908 | static | |
a90917c3 | 909 | int _lttng_session_metadata_statedump(struct lttng_session *session) |
c099397a | 910 | { |
30bdb6e4 | 911 | unsigned char *uuid_c = session->uuid.b; |
a82c63f1 | 912 | unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN]; |
a90917c3 MD |
913 | struct lttng_channel *chan; |
914 | struct lttng_event *event; | |
c099397a MD |
915 | int ret = 0; |
916 | ||
917 | if (!ACCESS_ONCE(session->active)) | |
918 | return 0; | |
919 | if (session->metadata_dumped) | |
920 | goto skip_session; | |
f40270ad | 921 | if (!session->metadata) { |
cd4bd11f | 922 | printk(KERN_WARNING "LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n"); |
f40270ad MD |
923 | return -EPERM; |
924 | } | |
c099397a | 925 | |
d793d5e1 | 926 | snprintf(uuid_s, sizeof(uuid_s), |
30bdb6e4 MD |
927 | "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x", |
928 | uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3], | |
929 | uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7], | |
930 | uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11], | |
931 | uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]); | |
d793d5e1 MD |
932 | |
933 | ret = lttng_metadata_printf(session, | |
9115fbdc MD |
934 | "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n" |
935 | "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n" | |
936 | "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n" | |
937 | "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n" | |
a9afe705 | 938 | "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n" |
9115fbdc MD |
939 | "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n" |
940 | "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n" | |
d793d5e1 MD |
941 | "\n" |
942 | "trace {\n" | |
943 | " major = %u;\n" | |
944 | " minor = %u;\n" | |
30bdb6e4 | 945 | " uuid = \"%s\";\n" |
d793d5e1 MD |
946 | " byte_order = %s;\n" |
947 | " packet.header := struct {\n" | |
948 | " uint32_t magic;\n" | |
1ec3f75a | 949 | " uint8_t uuid[16];\n" |
d793d5e1 | 950 | " uint32_t stream_id;\n" |
0eb25f58 | 951 | " };\n" |
d793d5e1 | 952 | "};\n\n", |
a90917c3 MD |
953 | lttng_alignof(uint8_t) * CHAR_BIT, |
954 | lttng_alignof(uint16_t) * CHAR_BIT, | |
955 | lttng_alignof(uint32_t) * CHAR_BIT, | |
956 | lttng_alignof(uint64_t) * CHAR_BIT, | |
a9afe705 MD |
957 | sizeof(unsigned long) * CHAR_BIT, |
958 | lttng_alignof(unsigned long) * CHAR_BIT, | |
c6c9e10f MD |
959 | CTF_SPEC_MAJOR, |
960 | CTF_SPEC_MINOR, | |
d793d5e1 MD |
961 | uuid_s, |
962 | #ifdef __BIG_ENDIAN | |
963 | "be" | |
964 | #else | |
965 | "le" | |
966 | #endif | |
967 | ); | |
968 | if (ret) | |
969 | goto end; | |
970 | ||
99dc9597 MD |
971 | ret = lttng_metadata_printf(session, |
972 | "env {\n" | |
a6058143 | 973 | " hostname = \"%s\";\n" |
c6c9e10f | 974 | " domain = \"kernel\";\n" |
99dc9597 | 975 | " sysname = \"%s\";\n" |
c6c9e10f MD |
976 | " kernel_release = \"%s\";\n" |
977 | " kernel_version = \"%s\";\n" | |
978 | " tracer_name = \"lttng-modules\";\n" | |
979 | " tracer_major = %d;\n" | |
980 | " tracer_minor = %d;\n" | |
981 | " tracer_patchlevel = %d;\n" | |
99dc9597 | 982 | "};\n\n", |
3d0d43db | 983 | current->nsproxy->uts_ns->name.nodename, |
99dc9597 MD |
984 | utsname()->sysname, |
985 | utsname()->release, | |
c6c9e10f MD |
986 | utsname()->version, |
987 | LTTNG_MODULES_MAJOR_VERSION, | |
988 | LTTNG_MODULES_MINOR_VERSION, | |
989 | LTTNG_MODULES_PATCHLEVEL_VERSION | |
99dc9597 MD |
990 | ); |
991 | if (ret) | |
992 | goto end; | |
993 | ||
a3ccff4f MD |
994 | ret = lttng_metadata_printf(session, |
995 | "clock {\n" | |
a82c63f1 MD |
996 | " name = %s;\n", |
997 | "monotonic" | |
998 | ); | |
999 | if (ret) | |
1000 | goto end; | |
1001 | ||
1002 | if (!trace_clock_uuid(clock_uuid_s)) { | |
1003 | ret = lttng_metadata_printf(session, | |
7c27cb17 | 1004 | " uuid = \"%s\";\n", |
a82c63f1 MD |
1005 | clock_uuid_s |
1006 | ); | |
1007 | if (ret) | |
1008 | goto end; | |
1009 | } | |
1010 | ||
1011 | ret = lttng_metadata_printf(session, | |
a3ccff4f MD |
1012 | " description = \"Monotonic Clock\";\n" |
1013 | " freq = %llu; /* Frequency, in Hz */\n" | |
1014 | " /* clock value offset from Epoch is: offset * (1/freq) */\n" | |
1015 | " offset = %llu;\n" | |
1016 | "};\n\n", | |
a3ccff4f MD |
1017 | (unsigned long long) trace_clock_freq(), |
1018 | (unsigned long long) measure_clock_offset() | |
1019 | ); | |
1020 | if (ret) | |
1021 | goto end; | |
1022 | ||
1023 | ret = lttng_metadata_printf(session, | |
1024 | "typealias integer {\n" | |
1025 | " size = 27; align = 1; signed = false;\n" | |
1026 | " map = clock.monotonic.value;\n" | |
1027 | "} := uint27_clock_monotonic_t;\n" | |
1028 | "\n" | |
1029 | "typealias integer {\n" | |
1030 | " size = 32; align = %u; signed = false;\n" | |
1031 | " map = clock.monotonic.value;\n" | |
1032 | "} := uint32_clock_monotonic_t;\n" | |
1033 | "\n" | |
1034 | "typealias integer {\n" | |
1035 | " size = 64; align = %u; signed = false;\n" | |
1036 | " map = clock.monotonic.value;\n" | |
1037 | "} := uint64_clock_monotonic_t;\n\n", | |
1038 | lttng_alignof(uint32_t) * CHAR_BIT, | |
1039 | lttng_alignof(uint64_t) * CHAR_BIT | |
1040 | ); | |
1041 | if (ret) | |
1042 | goto end; | |
1043 | ||
a90917c3 | 1044 | ret = _lttng_stream_packet_context_declare(session); |
9115fbdc MD |
1045 | if (ret) |
1046 | goto end; | |
1047 | ||
a90917c3 | 1048 | ret = _lttng_event_header_declare(session); |
9115fbdc MD |
1049 | if (ret) |
1050 | goto end; | |
1051 | ||
c099397a MD |
1052 | skip_session: |
1053 | list_for_each_entry(chan, &session->chan, list) { | |
a90917c3 | 1054 | ret = _lttng_channel_metadata_statedump(session, chan); |
c099397a MD |
1055 | if (ret) |
1056 | goto end; | |
1057 | } | |
1058 | ||
1059 | list_for_each_entry(event, &session->events, list) { | |
a90917c3 | 1060 | ret = _lttng_event_metadata_statedump(session, event->chan, event); |
c099397a MD |
1061 | if (ret) |
1062 | goto end; | |
1063 | } | |
1064 | session->metadata_dumped = 1; | |
1065 | end: | |
1066 | return ret; | |
1067 | } | |
1068 | ||
c0e31d2e | 1069 | /** |
a90917c3 | 1070 | * lttng_transport_register - LTT transport registration |
c0e31d2e MD |
1071 | * @transport: transport structure |
1072 | * | |
1073 | * Registers a transport which can be used as output to extract the data out of | |
1074 | * LTTng. The module calling this registration function must ensure that no | |
1075 | * trap-inducing code will be executed by the transport functions. E.g. | |
1076 | * vmalloc_sync_all() must be called between a vmalloc and the moment the memory | |
1077 | * is made visible to the transport function. This registration acts as a | |
1078 | * vmalloc_sync_all. Therefore, only if the module allocates virtual memory | |
1079 | * after its registration must it synchronize the TLBs. | |
1080 | */ | |
a90917c3 | 1081 | void lttng_transport_register(struct lttng_transport *transport) |
c0e31d2e MD |
1082 | { |
1083 | /* | |
1084 | * Make sure no page fault can be triggered by the module about to be | |
1085 | * registered. We deal with this here so we don't have to call | |
1086 | * vmalloc_sync_all() in each module's init. | |
1087 | */ | |
6d2a620c | 1088 | wrapper_vmalloc_sync_all(); |
c0e31d2e MD |
1089 | |
1090 | mutex_lock(&sessions_mutex); | |
a90917c3 | 1091 | list_add_tail(&transport->node, <tng_transport_list); |
c0e31d2e MD |
1092 | mutex_unlock(&sessions_mutex); |
1093 | } | |
a90917c3 | 1094 | EXPORT_SYMBOL_GPL(lttng_transport_register); |
c0e31d2e MD |
1095 | |
1096 | /** | |
a90917c3 | 1097 | * lttng_transport_unregister - LTT transport unregistration |
c0e31d2e MD |
1098 | * @transport: transport structure |
1099 | */ | |
a90917c3 | 1100 | void lttng_transport_unregister(struct lttng_transport *transport) |
c0e31d2e MD |
1101 | { |
1102 | mutex_lock(&sessions_mutex); | |
1103 | list_del(&transport->node); | |
1104 | mutex_unlock(&sessions_mutex); | |
1105 | } | |
a90917c3 | 1106 | EXPORT_SYMBOL_GPL(lttng_transport_unregister); |
c0e31d2e | 1107 | |
a90917c3 | 1108 | static int __init lttng_events_init(void) |
4e3c1b9b | 1109 | { |
1c25284c MD |
1110 | int ret; |
1111 | ||
a90917c3 | 1112 | event_cache = KMEM_CACHE(lttng_event, 0); |
11b5a3c2 | 1113 | if (!event_cache) |
4e3c1b9b | 1114 | return -ENOMEM; |
80996790 | 1115 | ret = lttng_abi_init(); |
02119ee5 MD |
1116 | if (ret) |
1117 | goto error_abi; | |
4e3c1b9b | 1118 | return 0; |
02119ee5 | 1119 | error_abi: |
1c25284c MD |
1120 | kmem_cache_destroy(event_cache); |
1121 | return ret; | |
4e3c1b9b MD |
1122 | } |
1123 | ||
a90917c3 | 1124 | module_init(lttng_events_init); |
11b5a3c2 | 1125 | |
a90917c3 | 1126 | static void __exit lttng_events_exit(void) |
4e3c1b9b | 1127 | { |
a90917c3 | 1128 | struct lttng_session *session, *tmpsession; |
92e94819 | 1129 | |
80996790 | 1130 | lttng_abi_exit(); |
92e94819 | 1131 | list_for_each_entry_safe(session, tmpsession, &sessions, list) |
a90917c3 | 1132 | lttng_session_destroy(session); |
11b5a3c2 | 1133 | kmem_cache_destroy(event_cache); |
4e3c1b9b | 1134 | } |
92e94819 | 1135 | |
a90917c3 | 1136 | module_exit(lttng_events_exit); |
11b5a3c2 | 1137 | |
92e94819 MD |
1138 | MODULE_LICENSE("GPL and additional rights"); |
1139 | MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>"); | |
1140 | MODULE_DESCRIPTION("LTTng Events"); |