4 * Linux Trace Toolkit Control Library Header File
6 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
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.
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
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
27 #include <sys/types.h>
29 /* Error codes that can be returned by API calls */
30 #include <lttng/lttng-error.h>
37 * Event symbol length. Copied from LTTng kernel ABI.
39 #define LTTNG_SYMBOL_NAME_LEN 256
42 * Every lttng_event_* structure both apply to kernel event and user-space
47 * Domain types: the different possible tracers.
49 enum lttng_domain_type
{
50 LTTNG_DOMAIN_KERNEL
= 1,
54 * For now, the domains below are not implemented. However, we keep them
55 * here in order to retain their enum values for future development. Note
56 * that it is on the roadmap to implement them.
58 LTTNG_DOMAIN_UST_EXEC_NAME = 3,
59 LTTNG_DOMAIN_UST_PID = 4,
60 LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
65 * Instrumentation type of tracing event.
67 enum lttng_event_type
{
69 LTTNG_EVENT_TRACEPOINT
= 0,
70 LTTNG_EVENT_PROBE
= 1,
71 LTTNG_EVENT_FUNCTION
= 2,
72 LTTNG_EVENT_FUNCTION_ENTRY
= 3,
74 LTTNG_EVENT_SYSCALL
= 5,
78 * Loglevel information.
80 enum lttng_loglevel_type
{
81 LTTNG_EVENT_LOGLEVEL_ALL
= 0,
82 LTTNG_EVENT_LOGLEVEL_RANGE
= 1,
83 LTTNG_EVENT_LOGLEVEL_SINGLE
= 2,
87 * Available loglevels.
90 LTTNG_LOGLEVEL_EMERG
= 0,
91 LTTNG_LOGLEVEL_ALERT
= 1,
92 LTTNG_LOGLEVEL_CRIT
= 2,
93 LTTNG_LOGLEVEL_ERR
= 3,
94 LTTNG_LOGLEVEL_WARNING
= 4,
95 LTTNG_LOGLEVEL_NOTICE
= 5,
96 LTTNG_LOGLEVEL_INFO
= 6,
97 LTTNG_LOGLEVEL_DEBUG_SYSTEM
= 7,
98 LTTNG_LOGLEVEL_DEBUG_PROGRAM
= 8,
99 LTTNG_LOGLEVEL_DEBUG_PROCESS
= 9,
100 LTTNG_LOGLEVEL_DEBUG_MODULE
= 10,
101 LTTNG_LOGLEVEL_DEBUG_UNIT
= 11,
102 LTTNG_LOGLEVEL_DEBUG_FUNCTION
= 12,
103 LTTNG_LOGLEVEL_DEBUG_LINE
= 13,
104 LTTNG_LOGLEVEL_DEBUG
= 14,
108 * LTTng consumer mode
110 enum lttng_event_output
{
111 LTTNG_EVENT_SPLICE
= 0,
112 LTTNG_EVENT_MMAP
= 1,
115 /* Event context possible type */
116 enum lttng_event_context_type
{
117 LTTNG_EVENT_CONTEXT_PID
= 0,
118 LTTNG_EVENT_CONTEXT_PERF_COUNTER
= 1,
119 LTTNG_EVENT_CONTEXT_PROCNAME
= 2,
120 LTTNG_EVENT_CONTEXT_PRIO
= 3,
121 LTTNG_EVENT_CONTEXT_NICE
= 4,
122 LTTNG_EVENT_CONTEXT_VPID
= 5,
123 LTTNG_EVENT_CONTEXT_TID
= 6,
124 LTTNG_EVENT_CONTEXT_VTID
= 7,
125 LTTNG_EVENT_CONTEXT_PPID
= 8,
126 LTTNG_EVENT_CONTEXT_VPPID
= 9,
127 LTTNG_EVENT_CONTEXT_PTHREAD_ID
= 10,
128 LTTNG_EVENT_CONTEXT_HOSTNAME
= 11,
131 enum lttng_calibrate_type
{
132 LTTNG_CALIBRATE_FUNCTION
= 0,
135 /* Health component for the health check function. */
136 enum lttng_health_component
{
138 LTTNG_HEALTH_APP_MANAGE
,
139 LTTNG_HEALTH_APP_REG
,
141 LTTNG_HEALTH_CONSUMER
,
146 * The structures should be initialized to zero before use.
148 #define LTTNG_DOMAIN_PADDING1 16
149 #define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
150 struct lttng_domain
{
151 enum lttng_domain_type type
;
152 char padding
[LTTNG_DOMAIN_PADDING1
];
156 char exec_name
[NAME_MAX
];
157 char padding
[LTTNG_DOMAIN_PADDING2
];
162 * Perf counter attributes
164 * The structures should be initialized to zero before use.
166 #define LTTNG_PERF_EVENT_PADDING1 16
167 struct lttng_event_perf_counter_ctx
{
170 char name
[LTTNG_SYMBOL_NAME_LEN
];
172 char padding
[LTTNG_PERF_EVENT_PADDING1
];
176 * Event/channel context
178 * The structures should be initialized to zero before use.
180 #define LTTNG_EVENT_CONTEXT_PADDING1 16
181 #define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
182 struct lttng_event_context
{
183 enum lttng_event_context_type ctx
;
184 char padding
[LTTNG_EVENT_CONTEXT_PADDING1
];
187 struct lttng_event_perf_counter_ctx perf_counter
;
188 char padding
[LTTNG_EVENT_CONTEXT_PADDING2
];
195 * Either addr is used or symbol_name and offset.
197 * The structures should be initialized to zero before use.
199 #define LTTNG_EVENT_PROBE_PADDING1 16
200 struct lttng_event_probe_attr
{
204 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
206 char padding
[LTTNG_EVENT_PROBE_PADDING1
];
212 * The structures should be initialized to zero before use.
214 #define LTTNG_EVENT_FUNCTION_PADDING1 16
215 struct lttng_event_function_attr
{
216 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
218 char padding
[LTTNG_EVENT_FUNCTION_PADDING1
];
222 * Generic lttng event
224 * The structures should be initialized to zero before use.
226 #define LTTNG_EVENT_PADDING1 15
227 #define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
229 enum lttng_event_type type
;
230 char name
[LTTNG_SYMBOL_NAME_LEN
];
232 enum lttng_loglevel_type loglevel_type
;
235 int32_t enabled
; /* Does not apply: -1 */
237 unsigned char filter
; /* filter enabled ? */
239 char padding
[LTTNG_EVENT_PADDING1
];
241 /* Per event type configuration */
243 struct lttng_event_probe_attr probe
;
244 struct lttng_event_function_attr ftrace
;
246 char padding
[LTTNG_EVENT_PADDING2
];
250 enum lttng_event_field_type
{
251 LTTNG_EVENT_FIELD_OTHER
= 0,
252 LTTNG_EVENT_FIELD_INTEGER
= 1,
253 LTTNG_EVENT_FIELD_ENUM
= 2,
254 LTTNG_EVENT_FIELD_FLOAT
= 3,
255 LTTNG_EVENT_FIELD_STRING
= 4,
258 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
259 struct lttng_event_field
{
260 char field_name
[LTTNG_SYMBOL_NAME_LEN
];
261 enum lttng_event_field_type type
;
262 char padding
[LTTNG_EVENT_FIELD_PADDING
];
263 struct lttng_event event
;
267 * Tracer channel attributes. For both kernel and user-space.
269 * The structures should be initialized to zero before use.
271 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 32
272 struct lttng_channel_attr
{
273 int overwrite
; /* 1: overwrite, 0: discard */
274 uint64_t subbuf_size
; /* bytes */
275 uint64_t num_subbuf
; /* power of 2 */
276 unsigned int switch_timer_interval
; /* usec */
277 unsigned int read_timer_interval
; /* usec */
278 enum lttng_event_output output
; /* splice, mmap */
280 char padding
[LTTNG_CHANNEL_ATTR_PADDING1
];
284 * Channel information structure. For both kernel and user-space.
286 * The structures should be initialized to zero before use.
288 #define LTTNG_CHANNEL_PADDING1 16
289 struct lttng_channel
{
290 char name
[LTTNG_SYMBOL_NAME_LEN
];
292 struct lttng_channel_attr attr
;
294 char padding
[LTTNG_CHANNEL_PADDING1
];
297 #define LTTNG_CALIBRATE_PADDING1 16
298 struct lttng_calibrate
{
299 enum lttng_calibrate_type type
;
301 char padding
[LTTNG_CALIBRATE_PADDING1
];
305 * Basic session information.
307 * This is an 'output data' meaning that it only comes *from* the session
308 * daemon *to* the lttng client. It's basically a 'human' representation of
309 * tracing entities (here a session).
311 * The structures should be initialized to zero before use.
313 #define LTTNG_SESSION_PADDING1 16
314 struct lttng_session
{
316 /* The path where traces are written */
318 uint32_t enabled
; /* enabled/started: 1, disabled/stopped: 0 */
320 char padding
[LTTNG_SESSION_PADDING1
];
324 * Handle used as a context for commands.
326 * The structures should be initialized to zero before use.
328 #define LTTNG_HANDLE_PADDING1 16
329 struct lttng_handle
{
330 char session_name
[NAME_MAX
];
331 struct lttng_domain domain
;
333 char padding
[LTTNG_HANDLE_PADDING1
];
337 * Public LTTng control API
339 * For functions having an lttng domain type as parameter, if a bad value is
340 * given, NO default is applied and an error is returned.
342 * On success, all functions of the API return 0 or the size of the allocated
345 * On error, a negative value is returned being a specific lttng-tools error
346 * code which can be humanly interpreted with lttng_strerror(err).
348 * Exceptions to this are noted below.
352 * Create a handle used as a context for every request made to the library.
354 * This handle contains the session name and lttng domain on which the command
356 * The returned pointer will be NULL in case of malloc() error.
358 extern struct lttng_handle
*lttng_create_handle(const char *session_name
,
359 struct lttng_domain
*domain
);
362 * Destroy a handle. This will simply free(3) the data pointer returned by
363 * lttng_create_handle(), rendering it unusable.
365 extern void lttng_destroy_handle(struct lttng_handle
*handle
);
368 * Create a tracing session using a name and an optional URL.
370 * If _url_ is NULL, no consumer is created for the session.
372 extern int lttng_create_session(const char *name
, const char *url
);
375 * Destroy a tracing session.
377 * The session will not be usable anymore, tracing will be stopped for all
378 * registered traces, and the tracing buffers will be flushed.
380 extern int lttng_destroy_session(const char *name
);
383 * List all the tracing sessions.
385 * Return the size (number of entries) of the "lttng_session" array. Caller
388 extern int lttng_list_sessions(struct lttng_session
**sessions
);
391 * List the registered domain(s) of a session.
393 * Return the size (number of entries) of the "lttng_domain" array. Caller
396 extern int lttng_list_domains(const char *session_name
,
397 struct lttng_domain
**domains
);
400 * List the channel(s) of a session.
402 * Return the size (number of entries) of the "lttng_channel" array. Caller
405 extern int lttng_list_channels(struct lttng_handle
*handle
,
406 struct lttng_channel
**channels
);
409 * List the event(s) of a session channel.
411 * Return the size (number of entries) of the "lttng_event" array.
412 * Caller must free(3).
414 extern int lttng_list_events(struct lttng_handle
*handle
,
415 const char *channel_name
, struct lttng_event
**events
);
418 * List the available tracepoints of a specific lttng domain.
420 * Return the size (number of entries) of the "lttng_event" array.
421 * Caller must free(3).
423 extern int lttng_list_tracepoints(struct lttng_handle
*handle
,
424 struct lttng_event
**events
);
427 * List the available tracepoints fields of a specific lttng domain.
429 * Return the size (number of entries) of the "lttng_event_field" array.
430 * Caller must free(3).
432 extern int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
433 struct lttng_event_field
**fields
);
436 * Check if a session daemon is alive.
438 * Return 1 if alive or 0 if not. On error returns a negative value.
440 extern int lttng_session_daemon_alive(void);
443 * Set the tracing group for the *current* flow of execution.
445 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
447 extern int lttng_set_tracing_group(const char *name
);
450 * Return a human-readable error message for an lttng-tools error code.
452 * Parameter MUST be a negative value or else you'll get a generic message.
454 extern const char *lttng_strerror(int code
);
457 * This call registers an "outside consumer" for a session and an lttng domain.
458 * No consumer will be spawned and all fds/commands will go through the socket
459 * path given (socket_path).
461 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
462 * command socket. The error socket is not supported yet for roaming consumers.
464 extern int lttng_register_consumer(struct lttng_handle
*handle
,
465 const char *socket_path
);
468 * Start tracing for *all* registered traces (kernel and user-space).
470 extern int lttng_start_tracing(const char *session_name
);
473 * Stop tracing for *all* registered traces (kernel and user-space).
475 extern int lttng_stop_tracing(const char *session_name
);
478 * Add context to event(s) for a specific channel (or for all).
480 * If event_name is NULL, the context is applied to all events of the channel.
481 * If channel_name is NULL, a lookup of the event's channel is done.
482 * If both are NULL, the context is applied to all events of all channels.
484 extern int lttng_add_context(struct lttng_handle
*handle
,
485 struct lttng_event_context
*ctx
, const char *event_name
,
486 const char *channel_name
);
489 * Create or enable an event (or events) for a channel.
491 * If the event you are trying to enable does not exist, it will be created,
492 * else it is enabled.
493 * If event_name is NULL, all events are enabled.
494 * If channel_name is NULL, the default channel is used (channel0).
496 extern int lttng_enable_event(struct lttng_handle
*handle
,
497 struct lttng_event
*ev
, const char *channel_name
);
500 * Apply a filter expression to an event.
502 * If event_name is NULL, the filter is applied to all events of the channel.
503 * If channel_name is NULL, a lookup of the event's channel is done.
504 * If both are NULL, the filter is applied to all events of all channels.
506 extern int lttng_set_event_filter(struct lttng_handle
*handle
,
507 const char *event_name
,
508 const char *channel_name
,
509 const char *filter_expression
);
511 * Create or enable a channel.
512 * The channel name cannot be NULL.
514 extern int lttng_enable_channel(struct lttng_handle
*handle
,
515 struct lttng_channel
*chan
);
518 * Disable event(s) of a channel and domain.
520 * If event_name is NULL, all events are disabled.
521 * If channel_name is NULL, the default channel is used (channel0).
523 extern int lttng_disable_event(struct lttng_handle
*handle
,
524 const char *name
, const char *channel_name
);
529 * The channel name cannot be NULL.
531 extern int lttng_disable_channel(struct lttng_handle
*handle
,
535 * Calibrate LTTng overhead.
537 extern int lttng_calibrate(struct lttng_handle
*handle
,
538 struct lttng_calibrate
*calibrate
);
541 * Set the default channel attributes for a specific domain and an allocated
542 * lttng_channel_attr pointer.
544 * If either or both of the arguments are NULL, nothing happens.
546 extern void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
547 struct lttng_channel_attr
*attr
);
550 * Set URL for a consumer for a session and domain.
552 * Both data and control URL must be defined. If both URLs are the same, only
553 * the control URL is used even for network streaming.
555 * Default port are 5342 and 5343 respectively for control and data which uses
558 extern int lttng_set_consumer_url(struct lttng_handle
*handle
,
559 const char *control_url
, const char *data_url
);
562 * Enable the consumer for a session and domain.
564 extern int lttng_enable_consumer(struct lttng_handle
*handle
);
567 * Disable consumer for a session and domain.
569 extern int lttng_disable_consumer(struct lttng_handle
*handle
);
572 * Check session daemon health for a specific component.
574 * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
575 * the control library was not able to connect to the session daemon health
578 * Any other positive value is an lttcomm error which can be translate with
581 extern int lttng_health_check(enum lttng_health_component c
);