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