d421ca518987fb506916fd02359ba9eef06bf63e
[lttng-tools.git] / include / lttng / lttng.h
1 /*
2 * lttng.h
3 *
4 * Linux Trace Toolkit Control Library Header File
5 *
6 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
7 *
8 * This library is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU Lesser General Public License, version 2.1 only,
10 * as published by the Free Software Foundation.
11 *
12 * This library is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
15 * for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this library; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #ifndef _LTTNG_H
23 #define _LTTNG_H
24
25 #include <limits.h>
26 #include <stdint.h>
27 #include <sys/types.h>
28
29 /*
30 * Event symbol length. Copied from LTTng kernel ABI.
31 */
32 #define LTTNG_SYMBOL_NAME_LEN 256
33
34 /*
35 * Maximum length of a domain name. This is the limit for the total length of a
36 * domain name specified by the RFC 1035 (https://www.ietf.org/rfc/rfc1035.txt)
37 */
38 #define LTTNG_MAX_DNNAME 255
39
40 /*
41 * Every lttng_event_* structure both apply to kernel event and user-space
42 * event.
43 */
44
45 /*
46 * Domain types: the different possible tracers.
47 */
48 enum lttng_domain_type {
49 LTTNG_DOMAIN_KERNEL = 1,
50 LTTNG_DOMAIN_UST = 2,
51
52 /*
53 * For now, the domains below are not implemented. However, we keep them
54 * here in order to retain their enum values for future development. Note
55 * that it is on the roadmap to implement them.
56 *
57 LTTNG_DOMAIN_UST_EXEC_NAME = 3,
58 LTTNG_DOMAIN_UST_PID = 4,
59 LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
60 */
61 };
62
63 /*
64 * Instrumentation type of tracing event.
65 */
66 enum lttng_event_type {
67 LTTNG_EVENT_ALL = -1,
68 LTTNG_EVENT_TRACEPOINT = 0,
69 LTTNG_EVENT_PROBE = 1,
70 LTTNG_EVENT_FUNCTION = 2,
71 LTTNG_EVENT_FUNCTION_ENTRY = 3,
72 LTTNG_EVENT_NOOP = 4,
73 LTTNG_EVENT_SYSCALL = 5,
74 };
75
76 /*
77 * Loglevel information.
78 */
79 enum lttng_loglevel_type {
80 LTTNG_EVENT_LOGLEVEL_ALL = 0,
81 LTTNG_EVENT_LOGLEVEL_RANGE = 1,
82 LTTNG_EVENT_LOGLEVEL_SINGLE = 2,
83 };
84
85 /*
86 * Available loglevels.
87 */
88 enum lttng_loglevel {
89 LTTNG_LOGLEVEL_EMERG = 0,
90 LTTNG_LOGLEVEL_ALERT = 1,
91 LTTNG_LOGLEVEL_CRIT = 2,
92 LTTNG_LOGLEVEL_ERR = 3,
93 LTTNG_LOGLEVEL_WARNING = 4,
94 LTTNG_LOGLEVEL_NOTICE = 5,
95 LTTNG_LOGLEVEL_INFO = 6,
96 LTTNG_LOGLEVEL_DEBUG_SYSTEM = 7,
97 LTTNG_LOGLEVEL_DEBUG_PROGRAM = 8,
98 LTTNG_LOGLEVEL_DEBUG_PROCESS = 9,
99 LTTNG_LOGLEVEL_DEBUG_MODULE = 10,
100 LTTNG_LOGLEVEL_DEBUG_UNIT = 11,
101 LTTNG_LOGLEVEL_DEBUG_FUNCTION = 12,
102 LTTNG_LOGLEVEL_DEBUG_LINE = 13,
103 LTTNG_LOGLEVEL_DEBUG = 14,
104 };
105
106 /*
107 * LTTng consumer mode
108 */
109 enum lttng_event_output {
110 LTTNG_EVENT_SPLICE = 0,
111 LTTNG_EVENT_MMAP = 1,
112 };
113
114 /* Event context possible type */
115 enum lttng_event_context_type {
116 LTTNG_EVENT_CONTEXT_PID = 0,
117 LTTNG_EVENT_CONTEXT_PERF_COUNTER = 1,
118 LTTNG_EVENT_CONTEXT_PROCNAME = 2,
119 LTTNG_EVENT_CONTEXT_PRIO = 3,
120 LTTNG_EVENT_CONTEXT_NICE = 4,
121 LTTNG_EVENT_CONTEXT_VPID = 5,
122 LTTNG_EVENT_CONTEXT_TID = 6,
123 LTTNG_EVENT_CONTEXT_VTID = 7,
124 LTTNG_EVENT_CONTEXT_PPID = 8,
125 LTTNG_EVENT_CONTEXT_VPPID = 9,
126 LTTNG_EVENT_CONTEXT_PTHREAD_ID = 10,
127 };
128
129 enum lttng_calibrate_type {
130 LTTNG_CALIBRATE_FUNCTION = 0,
131 };
132
133 /* Health component for the health check function. */
134 enum lttng_health_component {
135 LTTNG_HEALTH_CMD,
136 LTTNG_HEALTH_APP_MANAGE,
137 LTTNG_HEALTH_APP_REG,
138 LTTNG_HEALTH_KERNEL,
139 LTTNG_HEALTH_CONSUMER,
140 LTTNG_HEALTH_ALL,
141 };
142
143 /*
144 * The structures should be initialized to zero before use.
145 */
146 #define LTTNG_DOMAIN_PADDING1 16
147 #define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
148 struct lttng_domain {
149 enum lttng_domain_type type;
150 char padding[LTTNG_DOMAIN_PADDING1];
151
152 union {
153 pid_t pid;
154 char exec_name[NAME_MAX];
155 char padding[LTTNG_DOMAIN_PADDING2];
156 } attr;
157 };
158
159 /*
160 * Perf counter attributes
161 *
162 * The structures should be initialized to zero before use.
163 */
164 #define LTTNG_PERF_EVENT_PADDING1 16
165 struct lttng_event_perf_counter_ctx {
166 uint32_t type;
167 uint64_t config;
168 char name[LTTNG_SYMBOL_NAME_LEN];
169
170 char padding[LTTNG_PERF_EVENT_PADDING1];
171 };
172
173 /*
174 * Event/channel context
175 *
176 * The structures should be initialized to zero before use.
177 */
178 #define LTTNG_EVENT_CONTEXT_PADDING1 16
179 #define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
180 struct lttng_event_context {
181 enum lttng_event_context_type ctx;
182 char padding[LTTNG_EVENT_CONTEXT_PADDING1];
183
184 union {
185 struct lttng_event_perf_counter_ctx perf_counter;
186 char padding[LTTNG_EVENT_CONTEXT_PADDING2];
187 } u;
188 };
189
190 /*
191 * Event probe.
192 *
193 * Either addr is used or symbol_name and offset.
194 *
195 * The structures should be initialized to zero before use.
196 */
197 #define LTTNG_EVENT_PROBE_PADDING1 16
198 struct lttng_event_probe_attr {
199 uint64_t addr;
200
201 uint64_t offset;
202 char symbol_name[LTTNG_SYMBOL_NAME_LEN];
203
204 char padding[LTTNG_EVENT_PROBE_PADDING1];
205 };
206
207 /*
208 * Function tracer
209 *
210 * The structures should be initialized to zero before use.
211 */
212 #define LTTNG_EVENT_FUNCTION_PADDING1 16
213 struct lttng_event_function_attr {
214 char symbol_name[LTTNG_SYMBOL_NAME_LEN];
215
216 char padding[LTTNG_EVENT_FUNCTION_PADDING1];
217 };
218
219 /*
220 * Generic lttng event
221 *
222 * The structures should be initialized to zero before use.
223 */
224 #define LTTNG_EVENT_PADDING1 15
225 #define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
226 struct lttng_event {
227 enum lttng_event_type type;
228 char name[LTTNG_SYMBOL_NAME_LEN];
229
230 enum lttng_loglevel_type loglevel_type;
231 int loglevel;
232
233 int32_t enabled; /* Does not apply: -1 */
234 pid_t pid;
235 unsigned char filter; /* filter enabled ? */
236
237 char padding[LTTNG_EVENT_PADDING1];
238
239 /* Per event type configuration */
240 union {
241 struct lttng_event_probe_attr probe;
242 struct lttng_event_function_attr ftrace;
243
244 char padding[LTTNG_EVENT_PADDING2];
245 } attr;
246 };
247
248 enum lttng_event_field_type {
249 LTTNG_EVENT_FIELD_OTHER = 0,
250 LTTNG_EVENT_FIELD_INTEGER = 1,
251 LTTNG_EVENT_FIELD_ENUM = 2,
252 LTTNG_EVENT_FIELD_FLOAT = 3,
253 LTTNG_EVENT_FIELD_STRING = 4,
254 };
255
256 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
257 struct lttng_event_field {
258 char field_name[LTTNG_SYMBOL_NAME_LEN];
259 enum lttng_event_field_type type;
260 char padding[LTTNG_EVENT_FIELD_PADDING];
261 struct lttng_event event;
262 };
263
264 /*
265 * Tracer channel attributes. For both kernel and user-space.
266 *
267 * The structures should be initialized to zero before use.
268 */
269 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 32
270 struct lttng_channel_attr {
271 int overwrite; /* 1: overwrite, 0: discard */
272 uint64_t subbuf_size; /* bytes */
273 uint64_t num_subbuf; /* power of 2 */
274 unsigned int switch_timer_interval; /* usec */
275 unsigned int read_timer_interval; /* usec */
276 enum lttng_event_output output; /* splice, mmap */
277
278 char padding[LTTNG_CHANNEL_ATTR_PADDING1];
279 };
280
281 /*
282 * Channel information structure. For both kernel and user-space.
283 *
284 * The structures should be initialized to zero before use.
285 */
286 #define LTTNG_CHANNEL_PADDING1 16
287 struct lttng_channel {
288 char name[LTTNG_SYMBOL_NAME_LEN];
289 uint32_t enabled;
290 struct lttng_channel_attr attr;
291
292 char padding[LTTNG_CHANNEL_PADDING1];
293 };
294
295 #define LTTNG_CALIBRATE_PADDING1 16
296 struct lttng_calibrate {
297 enum lttng_calibrate_type type;
298
299 char padding[LTTNG_CALIBRATE_PADDING1];
300 };
301
302 /*
303 * Basic session information.
304 *
305 * This is an 'output data' meaning that it only comes *from* the session
306 * daemon *to* the lttng client. It's basically a 'human' representation of
307 * tracing entities (here a session).
308 *
309 * The structures should be initialized to zero before use.
310 */
311 #define LTTNG_SESSION_PADDING1 16
312 struct lttng_session {
313 char name[NAME_MAX];
314 /* The path where traces are written */
315 char path[PATH_MAX];
316 uint32_t enabled; /* enabled/started: 1, disabled/stopped: 0 */
317
318 char padding[LTTNG_SESSION_PADDING1];
319 };
320
321 /*
322 * Handle used as a context for commands.
323 *
324 * The structures should be initialized to zero before use.
325 */
326 #define LTTNG_HANDLE_PADDING1 16
327 struct lttng_handle {
328 char session_name[NAME_MAX];
329 struct lttng_domain domain;
330
331 char padding[LTTNG_HANDLE_PADDING1];
332 };
333
334 /*
335 * Public LTTng control API
336 *
337 * For functions having an lttng domain type as parameter, if a bad value is
338 * given, NO default is applied and an error is returned.
339 *
340 * On success, all functions of the API return 0 or the size of the allocated
341 * array (in bytes).
342 *
343 * On error, a negative value is returned being a specific lttng-tools error
344 * code which can be humanly interpreted with lttng_strerror(err).
345 *
346 * Exceptions to this are noted below.
347 */
348
349 /*
350 * Create a handle used as a context for every request made to the library.
351 *
352 * This handle contains the session name and lttng domain on which the command
353 * will be executed.
354 * The returned pointer will be NULL in case of malloc() error.
355 */
356 extern struct lttng_handle *lttng_create_handle(const char *session_name,
357 struct lttng_domain *domain);
358
359 /*
360 * Destroy a handle. This will simply free(3) the data pointer returned by
361 * lttng_create_handle(), rendering it unusable.
362 */
363 extern void lttng_destroy_handle(struct lttng_handle *handle);
364
365 /*
366 * Create a tracing session using a name and an optional URL.
367 *
368 * If _url_ is NULL, no consumer is created for the session.
369 */
370 extern int lttng_create_session(const char *name, const char *url);
371
372 /*
373 * Destroy a tracing session.
374 *
375 * The session will not be usable anymore, tracing will be stopped for all
376 * registered traces, and the tracing buffers will be flushed.
377 */
378 extern int lttng_destroy_session(const char *name);
379
380 /*
381 * List all the tracing sessions.
382 *
383 * Return the size (number of entries) of the "lttng_session" array. Caller
384 * must free(3).
385 */
386 extern int lttng_list_sessions(struct lttng_session **sessions);
387
388 /*
389 * List the registered domain(s) of a session.
390 *
391 * Return the size (number of entries) of the "lttng_domain" array. Caller
392 * must free(3).
393 */
394 extern int lttng_list_domains(const char *session_name,
395 struct lttng_domain **domains);
396
397 /*
398 * List the channel(s) of a session.
399 *
400 * Return the size (number of entries) of the "lttng_channel" array. Caller
401 * must free(3).
402 */
403 extern int lttng_list_channels(struct lttng_handle *handle,
404 struct lttng_channel **channels);
405
406 /*
407 * List the event(s) of a session channel.
408 *
409 * Return the size (number of entries) of the "lttng_event" array.
410 * Caller must free(3).
411 */
412 extern int lttng_list_events(struct lttng_handle *handle,
413 const char *channel_name, struct lttng_event **events);
414
415 /*
416 * List the available tracepoints of a specific lttng domain.
417 *
418 * Return the size (number of entries) of the "lttng_event" array.
419 * Caller must free(3).
420 */
421 extern int lttng_list_tracepoints(struct lttng_handle *handle,
422 struct lttng_event **events);
423
424 /*
425 * List the available tracepoints fields of a specific lttng domain.
426 *
427 * Return the size (number of entries) of the "lttng_event_field" array.
428 * Caller must free(3).
429 */
430 extern int lttng_list_tracepoint_fields(struct lttng_handle *handle,
431 struct lttng_event_field **fields);
432
433 /*
434 * Check if a session daemon is alive.
435 *
436 * Return 1 if alive or 0 if not. On error returns a negative value.
437 */
438 extern int lttng_session_daemon_alive(void);
439
440 /*
441 * Set the tracing group for the *current* flow of execution.
442 *
443 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
444 */
445 extern int lttng_set_tracing_group(const char *name);
446
447 /*
448 * Return a human-readable error message for an lttng-tools error code.
449 *
450 * Parameter MUST be a negative value or else you'll get a generic message.
451 */
452 extern const char *lttng_strerror(int code);
453
454 /*
455 * This call registers an "outside consumer" for a session and an lttng domain.
456 * No consumer will be spawned and all fds/commands will go through the socket
457 * path given (socket_path).
458 *
459 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
460 * command socket. The error socket is not supported yet for roaming consumers.
461 */
462 extern int lttng_register_consumer(struct lttng_handle *handle,
463 const char *socket_path);
464
465 /*
466 * Start tracing for *all* registered traces (kernel and user-space).
467 */
468 extern int lttng_start_tracing(const char *session_name);
469
470 /*
471 * Stop tracing for *all* registered traces (kernel and user-space).
472 */
473 extern int lttng_stop_tracing(const char *session_name);
474
475 /*
476 * Add context to event(s) for a specific channel (or for all).
477 *
478 * If event_name is NULL, the context is applied to all events of the channel.
479 * If channel_name is NULL, a lookup of the event's channel is done.
480 * If both are NULL, the context is applied to all events of all channels.
481 */
482 extern int lttng_add_context(struct lttng_handle *handle,
483 struct lttng_event_context *ctx, const char *event_name,
484 const char *channel_name);
485
486 /*
487 * Create or enable an event (or events) for a channel.
488 *
489 * If the event you are trying to enable does not exist, it will be created,
490 * else it is enabled.
491 * If event_name is NULL, all events are enabled.
492 * If channel_name is NULL, the default channel is used (channel0).
493 */
494 extern int lttng_enable_event(struct lttng_handle *handle,
495 struct lttng_event *ev, const char *channel_name);
496
497 /*
498 * Apply a filter expression to an event.
499 *
500 * If event_name is NULL, the filter is applied to all events of the channel.
501 * If channel_name is NULL, a lookup of the event's channel is done.
502 * If both are NULL, the filter is applied to all events of all channels.
503 */
504 extern int lttng_set_event_filter(struct lttng_handle *handle,
505 const char *event_name,
506 const char *channel_name,
507 const char *filter_expression);
508 /*
509 * Create or enable a channel.
510 * The channel name cannot be NULL.
511 */
512 extern int lttng_enable_channel(struct lttng_handle *handle,
513 struct lttng_channel *chan);
514
515 /*
516 * Disable event(s) of a channel and domain.
517 *
518 * If event_name is NULL, all events are disabled.
519 * If channel_name is NULL, the default channel is used (channel0).
520 */
521 extern int lttng_disable_event(struct lttng_handle *handle,
522 const char *name, const char *channel_name);
523
524 /*
525 * Disable channel.
526 *
527 * The channel name cannot be NULL.
528 */
529 extern int lttng_disable_channel(struct lttng_handle *handle,
530 const char *name);
531
532 /*
533 * Calibrate LTTng overhead.
534 */
535 extern int lttng_calibrate(struct lttng_handle *handle,
536 struct lttng_calibrate *calibrate);
537
538 /*
539 * Set the default channel attributes for a specific domain and an allocated
540 * lttng_channel_attr pointer.
541 *
542 * If either or both of the arguments are NULL, nothing happens.
543 */
544 extern void lttng_channel_set_default_attr(struct lttng_domain *domain,
545 struct lttng_channel_attr *attr);
546
547 /*
548 * Set URL for a consumer for a session and domain.
549 *
550 * Both data and control URL must be defined. If both URLs are the same, only
551 * the control URL is used even for network streaming.
552 *
553 * Default port are 5342 and 5343 respectively for control and data which uses
554 * the TCP protocol.
555 */
556 extern int lttng_set_consumer_url(struct lttng_handle *handle,
557 const char *control_url, const char *data_url);
558
559 /*
560 * Enable the consumer for a session and domain.
561 */
562 extern int lttng_enable_consumer(struct lttng_handle *handle);
563
564 /*
565 * Disable consumer for a session and domain.
566 */
567 extern int lttng_disable_consumer(struct lttng_handle *handle);
568
569 /*
570 * Check session daemon health for a specific component.
571 *
572 * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
573 * the control library was not able to connect to the session daemon health
574 * socket.
575 *
576 * Any other positive value is an lttcomm error which can be translate with
577 * lttng_strerror().
578 */
579 extern int lttng_health_check(enum lttng_health_component c);
580
581 #endif /* _LTTNG_H */
This page took 0.063527 seconds and 4 git commands to generate.