Create kernel-consumer.c/.h and consumer.h
[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 * Every lttng_event_* structure both apply to kernel event and user-space
36 * event.
37 */
38
39 /*
40 * Domain types: the different possible tracers.
41 */
42 enum lttng_domain_type {
43 LTTNG_DOMAIN_KERNEL = 1,
44 LTTNG_DOMAIN_UST = 2,
45
46 /*
47 * For now, the domains below are not implemented. However, we keep them
48 * here in order to retain their enum values for future development. Note
49 * that it is on the roadmap to implement them.
50 *
51 LTTNG_DOMAIN_UST_EXEC_NAME = 3,
52 LTTNG_DOMAIN_UST_PID = 4,
53 LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
54 */
55 };
56
57 /*
58 * Instrumentation type of tracing event.
59 */
60 enum lttng_event_type {
61 LTTNG_EVENT_ALL = -1,
62 LTTNG_EVENT_TRACEPOINT = 0,
63 LTTNG_EVENT_PROBE = 1,
64 LTTNG_EVENT_FUNCTION = 2,
65 LTTNG_EVENT_FUNCTION_ENTRY = 3,
66 LTTNG_EVENT_NOOP = 4,
67 LTTNG_EVENT_SYSCALL = 5,
68 };
69
70 /*
71 * Loglevel information.
72 */
73 enum lttng_loglevel_type {
74 LTTNG_EVENT_LOGLEVEL_ALL = 0,
75 LTTNG_EVENT_LOGLEVEL_RANGE = 1,
76 LTTNG_EVENT_LOGLEVEL_SINGLE = 2,
77 };
78
79 /*
80 * Available loglevels.
81 */
82 enum lttng_loglevel {
83 LTTNG_LOGLEVEL_EMERG = 0,
84 LTTNG_LOGLEVEL_ALERT = 1,
85 LTTNG_LOGLEVEL_CRIT = 2,
86 LTTNG_LOGLEVEL_ERR = 3,
87 LTTNG_LOGLEVEL_WARNING = 4,
88 LTTNG_LOGLEVEL_NOTICE = 5,
89 LTTNG_LOGLEVEL_INFO = 6,
90 LTTNG_LOGLEVEL_DEBUG_SYSTEM = 7,
91 LTTNG_LOGLEVEL_DEBUG_PROGRAM = 8,
92 LTTNG_LOGLEVEL_DEBUG_PROCESS = 9,
93 LTTNG_LOGLEVEL_DEBUG_MODULE = 10,
94 LTTNG_LOGLEVEL_DEBUG_UNIT = 11,
95 LTTNG_LOGLEVEL_DEBUG_FUNCTION = 12,
96 LTTNG_LOGLEVEL_DEBUG_LINE = 13,
97 LTTNG_LOGLEVEL_DEBUG = 14,
98 };
99
100 /*
101 * LTTng consumer mode
102 */
103 enum lttng_event_output {
104 LTTNG_EVENT_SPLICE = 0,
105 LTTNG_EVENT_MMAP = 1,
106 };
107
108 /* Event context possible type */
109 enum lttng_event_context_type {
110 LTTNG_EVENT_CONTEXT_PID = 0,
111 LTTNG_EVENT_CONTEXT_PERF_COUNTER = 1,
112 LTTNG_EVENT_CONTEXT_PROCNAME = 2,
113 LTTNG_EVENT_CONTEXT_PRIO = 3,
114 LTTNG_EVENT_CONTEXT_NICE = 4,
115 LTTNG_EVENT_CONTEXT_VPID = 5,
116 LTTNG_EVENT_CONTEXT_TID = 6,
117 LTTNG_EVENT_CONTEXT_VTID = 7,
118 LTTNG_EVENT_CONTEXT_PPID = 8,
119 LTTNG_EVENT_CONTEXT_VPPID = 9,
120 LTTNG_EVENT_CONTEXT_PTHREAD_ID = 10,
121 };
122
123 enum lttng_calibrate_type {
124 LTTNG_CALIBRATE_FUNCTION = 0,
125 };
126
127 /*
128 * The structures should be initialized to zero before use.
129 */
130 #define LTTNG_DOMAIN_PADDING1 16
131 #define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
132 struct lttng_domain {
133 enum lttng_domain_type type;
134 char padding[LTTNG_DOMAIN_PADDING1];
135
136 union {
137 pid_t pid;
138 char exec_name[NAME_MAX];
139 char padding[LTTNG_DOMAIN_PADDING2];
140 } attr;
141 };
142
143 /*
144 * Perf counter attributes
145 *
146 * The structures should be initialized to zero before use.
147 */
148 #define LTTNG_PERF_EVENT_PADDING1 16
149 struct lttng_event_perf_counter_ctx {
150 uint32_t type;
151 uint64_t config;
152 char name[LTTNG_SYMBOL_NAME_LEN];
153
154 char padding[LTTNG_PERF_EVENT_PADDING1];
155 };
156
157 /*
158 * Event/channel context
159 *
160 * The structures should be initialized to zero before use.
161 */
162 #define LTTNG_EVENT_CONTEXT_PADDING1 16
163 #define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
164 struct lttng_event_context {
165 enum lttng_event_context_type ctx;
166 char padding[LTTNG_EVENT_CONTEXT_PADDING1];
167
168 union {
169 struct lttng_event_perf_counter_ctx perf_counter;
170 char padding[LTTNG_EVENT_CONTEXT_PADDING2];
171 } u;
172 };
173
174 /*
175 * Event probe.
176 *
177 * Either addr is used or symbol_name and offset.
178 *
179 * The structures should be initialized to zero before use.
180 */
181 #define LTTNG_EVENT_PROBE_PADDING1 16
182 struct lttng_event_probe_attr {
183 uint64_t addr;
184
185 uint64_t offset;
186 char symbol_name[LTTNG_SYMBOL_NAME_LEN];
187
188 char padding[LTTNG_EVENT_PROBE_PADDING1];
189 };
190
191 /*
192 * Function tracer
193 *
194 * The structures should be initialized to zero before use.
195 */
196 #define LTTNG_EVENT_FUNCTION_PADDING1 16
197 struct lttng_event_function_attr {
198 char symbol_name[LTTNG_SYMBOL_NAME_LEN];
199
200 char padding[LTTNG_EVENT_FUNCTION_PADDING1];
201 };
202
203 /*
204 * Generic lttng event
205 *
206 * The structures should be initialized to zero before use.
207 */
208 #define LTTNG_EVENT_PADDING1 16
209 #define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
210 struct lttng_event {
211 enum lttng_event_type type;
212 char name[LTTNG_SYMBOL_NAME_LEN];
213
214 enum lttng_loglevel_type loglevel_type;
215 int loglevel;
216
217 uint32_t enabled;
218 pid_t pid;
219
220 char padding[LTTNG_EVENT_PADDING1];
221
222 /* Per event type configuration */
223 union {
224 struct lttng_event_probe_attr probe;
225 struct lttng_event_function_attr ftrace;
226
227 char padding[LTTNG_EVENT_PADDING2];
228 } attr;
229 };
230
231 enum lttng_event_field_type {
232 LTTNG_EVENT_FIELD_OTHER = 0,
233 LTTNG_EVENT_FIELD_INTEGER = 1,
234 LTTNG_EVENT_FIELD_ENUM = 2,
235 LTTNG_EVENT_FIELD_FLOAT = 3,
236 LTTNG_EVENT_FIELD_STRING = 4,
237 };
238
239 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
240 struct lttng_event_field {
241 char field_name[LTTNG_SYMBOL_NAME_LEN];
242 enum lttng_event_field_type type;
243 char padding[LTTNG_EVENT_FIELD_PADDING];
244 struct lttng_event event;
245 };
246
247 /*
248 * Tracer channel attributes. For both kernel and user-space.
249 *
250 * The structures should be initialized to zero before use.
251 */
252 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 32
253 struct lttng_channel_attr {
254 int overwrite; /* 1: overwrite, 0: discard */
255 uint64_t subbuf_size; /* bytes */
256 uint64_t num_subbuf; /* power of 2 */
257 unsigned int switch_timer_interval; /* usec */
258 unsigned int read_timer_interval; /* usec */
259 enum lttng_event_output output; /* splice, mmap */
260
261 char padding[LTTNG_CHANNEL_ATTR_PADDING1];
262 };
263
264 /*
265 * Channel information structure. For both kernel and user-space.
266 *
267 * The structures should be initialized to zero before use.
268 */
269 #define LTTNG_CHANNEL_PADDING1 16
270 struct lttng_channel {
271 char name[LTTNG_SYMBOL_NAME_LEN];
272 uint32_t enabled;
273 struct lttng_channel_attr attr;
274
275 char padding[LTTNG_CHANNEL_PADDING1];
276 };
277
278 #define LTTNG_CALIBRATE_PADDING1 16
279 struct lttng_calibrate {
280 enum lttng_calibrate_type type;
281
282 char padding[LTTNG_CALIBRATE_PADDING1];
283 };
284
285 /*
286 * Basic session information.
287 *
288 * This is an 'output data' meaning that it only comes *from* the session
289 * daemon *to* the lttng client. It's basically a 'human' representation of
290 * tracing entities (here a session).
291 *
292 * The structures should be initialized to zero before use.
293 */
294 #define LTTNG_SESSION_PADDING1 16
295 struct lttng_session {
296 char name[NAME_MAX];
297 /* The path where traces are written */
298 char path[PATH_MAX];
299 uint32_t enabled; /* enabled/started: 1, disabled/stopped: 0 */
300
301 char padding[LTTNG_SESSION_PADDING1];
302 };
303
304 /*
305 * Handle used as a context for commands.
306 *
307 * The structures should be initialized to zero before use.
308 */
309 #define LTTNG_HANDLE_PADDING1 16
310 struct lttng_handle {
311 char session_name[NAME_MAX];
312 struct lttng_domain domain;
313
314 char padding[LTTNG_HANDLE_PADDING1];
315 };
316
317 /*
318 * Public LTTng control API
319 *
320 * For functions having an lttng domain type as parameter, if a bad value is
321 * given, NO default is applied and an error is returned.
322 *
323 * On success, all functions of the API return 0 or the size of the allocated
324 * array (in bytes).
325 *
326 * On error, a negative value is returned being a specific lttng-tools error
327 * code which can be humanly interpreted with lttng_strerror(err).
328 *
329 * Exceptions to this are noted below.
330 */
331
332 /*
333 * Create a handle used as a context for every request made to the library.
334 *
335 * This handle contains the session name and lttng domain on which the command
336 * will be executed.
337 * The returned pointer will be NULL in case of malloc() error.
338 */
339 extern struct lttng_handle *lttng_create_handle(const char *session_name,
340 struct lttng_domain *domain);
341
342 /*
343 * Destroy a handle. This will simply free(3) the data pointer returned by
344 * lttng_create_handle(), rendering it unusable.
345 */
346 extern void lttng_destroy_handle(struct lttng_handle *handle);
347
348 /*
349 * Create a tracing session using a name and a path where the trace will be
350 * written.
351 */
352 extern int lttng_create_session(const char *name, const char *path);
353
354 /*
355 * Destroy a tracing session.
356 *
357 * The session will not be usable anymore, tracing will be stopped for all
358 * registered traces, and the tracing buffers will be flushed.
359 */
360 extern int lttng_destroy_session(const char *name);
361
362 /*
363 * List all the tracing sessions.
364 *
365 * Return the size (number of entries) of the "lttng_session" array. Caller
366 * must free(3).
367 */
368 extern int lttng_list_sessions(struct lttng_session **sessions);
369
370 /*
371 * List the registered domain(s) of a session.
372 *
373 * Return the size (number of entries) of the "lttng_domain" array. Caller
374 * must free(3).
375 */
376 extern int lttng_list_domains(const char *session_name,
377 struct lttng_domain **domains);
378
379 /*
380 * List the channel(s) of a session.
381 *
382 * Return the size (number of entries) of the "lttng_channel" array. Caller
383 * must free(3).
384 */
385 extern int lttng_list_channels(struct lttng_handle *handle,
386 struct lttng_channel **channels);
387
388 /*
389 * List the event(s) of a session channel.
390 *
391 * Return the size (number of entries) of the "lttng_event" array.
392 * Caller must free(3).
393 */
394 extern int lttng_list_events(struct lttng_handle *handle,
395 const char *channel_name, struct lttng_event **events);
396
397 /*
398 * List the available tracepoints of a specific lttng domain.
399 *
400 * Return the size (number of entries) of the "lttng_event" array.
401 * Caller must free(3).
402 */
403 extern int lttng_list_tracepoints(struct lttng_handle *handle,
404 struct lttng_event **events);
405
406 /*
407 * List the available tracepoints fields of a specific lttng domain.
408 *
409 * Return the size (number of entries) of the "lttng_event_field" array.
410 * Caller must free(3).
411 */
412 extern int lttng_list_tracepoint_fields(struct lttng_handle *handle,
413 struct lttng_event_field **fields);
414
415 /*
416 * Check if a session daemon is alive.
417 *
418 * Return 1 if alive or 0 if not. On error returns a negative value.
419 */
420 extern int lttng_session_daemon_alive(void);
421
422 /*
423 * Set the tracing group for the *current* flow of execution.
424 *
425 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
426 */
427 extern int lttng_set_tracing_group(const char *name);
428
429 /*
430 * Return a human-readable error message for an lttng-tools error code.
431 *
432 * Parameter MUST be a negative value or else you'll get a generic message.
433 */
434 extern const char *lttng_strerror(int code);
435
436 /*
437 * This call registers an "outside consumer" for a session and an lttng domain.
438 * No consumer will be spawned and all fds/commands will go through the socket
439 * path given (socket_path).
440 *
441 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
442 * command socket. The error socket is not supported yet for roaming consumers.
443 */
444 extern int lttng_register_consumer(struct lttng_handle *handle,
445 const char *socket_path);
446
447 /*
448 * Start tracing for *all* registered traces (kernel and user-space).
449 */
450 extern int lttng_start_tracing(const char *session_name);
451
452 /*
453 * Stop tracing for *all* registered traces (kernel and user-space).
454 */
455 extern int lttng_stop_tracing(const char *session_name);
456
457 /*
458 * Add context to event(s) for a specific channel (or for all).
459 *
460 * If event_name is NULL, the context is applied to all events of the channel.
461 * If channel_name is NULL, a lookup of the event's channel is done.
462 * If both are NULL, the context is applied to all events of all channels.
463 */
464 extern int lttng_add_context(struct lttng_handle *handle,
465 struct lttng_event_context *ctx, const char *event_name,
466 const char *channel_name);
467
468 /*
469 * Create or enable an event (or events) for a channel.
470 *
471 * If the event you are trying to enable does not exist, it will be created,
472 * else it is enabled.
473 * If event_name is NULL, all events are enabled.
474 * If channel_name is NULL, the default channel is used (channel0).
475 */
476 extern int lttng_enable_event(struct lttng_handle *handle,
477 struct lttng_event *ev, const char *channel_name);
478
479 /*
480 * Create or enable a channel.
481 * The channel name cannot be NULL.
482 */
483 extern int lttng_enable_channel(struct lttng_handle *handle,
484 struct lttng_channel *chan);
485
486 /*
487 * Disable event(s) of a channel and domain.
488 *
489 * If event_name is NULL, all events are disabled.
490 * If channel_name is NULL, the default channel is used (channel0).
491 */
492 extern int lttng_disable_event(struct lttng_handle *handle,
493 const char *name, const char *channel_name);
494
495 /*
496 * Disable channel.
497 *
498 * The channel name cannot be NULL.
499 */
500 extern int lttng_disable_channel(struct lttng_handle *handle,
501 const char *name);
502
503 /*
504 * Calibrate LTTng overhead.
505 */
506 extern int lttng_calibrate(struct lttng_handle *handle,
507 struct lttng_calibrate *calibrate);
508
509 /*
510 * Set the default channel attributes for a specific domain and an allocated
511 * lttng_channel_attr pointer.
512 *
513 * If either or both of the arguments are NULL, nothing happens.
514 */
515 extern void lttng_channel_set_default_attr(struct lttng_domain *domain,
516 struct lttng_channel_attr *attr);
517
518 #endif /* _LTTNG_H */
This page took 0.061326 seconds and 4 git commands to generate.