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>
33 * Event symbol length. Copied from LTTng kernel ABI.
35 #define LTTNG_SYMBOL_NAME_LEN 256
38 * Every lttng_event_* structure both apply to kernel event and user-space
43 * Domain types: the different possible tracers.
45 enum lttng_domain_type
{
46 LTTNG_DOMAIN_KERNEL
= 1,
50 * For now, the domains below are not implemented. However, we keep them
51 * here in order to retain their enum values for future development. Note
52 * that it is on the roadmap to implement them.
54 LTTNG_DOMAIN_UST_EXEC_NAME = 3,
55 LTTNG_DOMAIN_UST_PID = 4,
56 LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
61 * Instrumentation type of tracing event.
63 enum lttng_event_type
{
65 LTTNG_EVENT_TRACEPOINT
= 0,
66 LTTNG_EVENT_PROBE
= 1,
67 LTTNG_EVENT_FUNCTION
= 2,
68 LTTNG_EVENT_FUNCTION_ENTRY
= 3,
70 LTTNG_EVENT_SYSCALL
= 5,
74 * Loglevel information.
76 enum lttng_loglevel_type
{
77 LTTNG_EVENT_LOGLEVEL_ALL
= 0,
78 LTTNG_EVENT_LOGLEVEL_RANGE
= 1,
79 LTTNG_EVENT_LOGLEVEL_SINGLE
= 2,
83 * Available loglevels.
86 LTTNG_LOGLEVEL_EMERG
= 0,
87 LTTNG_LOGLEVEL_ALERT
= 1,
88 LTTNG_LOGLEVEL_CRIT
= 2,
89 LTTNG_LOGLEVEL_ERR
= 3,
90 LTTNG_LOGLEVEL_WARNING
= 4,
91 LTTNG_LOGLEVEL_NOTICE
= 5,
92 LTTNG_LOGLEVEL_INFO
= 6,
93 LTTNG_LOGLEVEL_DEBUG_SYSTEM
= 7,
94 LTTNG_LOGLEVEL_DEBUG_PROGRAM
= 8,
95 LTTNG_LOGLEVEL_DEBUG_PROCESS
= 9,
96 LTTNG_LOGLEVEL_DEBUG_MODULE
= 10,
97 LTTNG_LOGLEVEL_DEBUG_UNIT
= 11,
98 LTTNG_LOGLEVEL_DEBUG_FUNCTION
= 12,
99 LTTNG_LOGLEVEL_DEBUG_LINE
= 13,
100 LTTNG_LOGLEVEL_DEBUG
= 14,
104 * LTTng consumer mode
106 enum lttng_event_output
{
107 LTTNG_EVENT_SPLICE
= 0,
108 LTTNG_EVENT_MMAP
= 1,
111 /* Event context possible type */
112 enum lttng_event_context_type
{
113 LTTNG_EVENT_CONTEXT_PID
= 0,
114 LTTNG_EVENT_CONTEXT_PERF_COUNTER
= 1,
115 LTTNG_EVENT_CONTEXT_PROCNAME
= 2,
116 LTTNG_EVENT_CONTEXT_PRIO
= 3,
117 LTTNG_EVENT_CONTEXT_NICE
= 4,
118 LTTNG_EVENT_CONTEXT_VPID
= 5,
119 LTTNG_EVENT_CONTEXT_TID
= 6,
120 LTTNG_EVENT_CONTEXT_VTID
= 7,
121 LTTNG_EVENT_CONTEXT_PPID
= 8,
122 LTTNG_EVENT_CONTEXT_VPPID
= 9,
123 LTTNG_EVENT_CONTEXT_PTHREAD_ID
= 10,
124 LTTNG_EVENT_CONTEXT_HOSTNAME
= 11,
127 enum lttng_calibrate_type
{
128 LTTNG_CALIBRATE_FUNCTION
= 0,
131 /* Health component for the health check function. */
132 enum lttng_health_component
{
134 LTTNG_HEALTH_APP_MANAGE
,
135 LTTNG_HEALTH_APP_REG
,
137 LTTNG_HEALTH_CONSUMER
,
142 * The structures should be initialized to zero before use.
144 #define LTTNG_DOMAIN_PADDING1 16
145 #define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
146 struct lttng_domain
{
147 enum lttng_domain_type type
;
148 char padding
[LTTNG_DOMAIN_PADDING1
];
152 char exec_name
[NAME_MAX
];
153 char padding
[LTTNG_DOMAIN_PADDING2
];
158 * Perf counter attributes
160 * The structures should be initialized to zero before use.
162 #define LTTNG_PERF_EVENT_PADDING1 16
163 struct lttng_event_perf_counter_ctx
{
166 char name
[LTTNG_SYMBOL_NAME_LEN
];
168 char padding
[LTTNG_PERF_EVENT_PADDING1
];
172 * Event/channel context
174 * The structures should be initialized to zero before use.
176 #define LTTNG_EVENT_CONTEXT_PADDING1 16
177 #define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
178 struct lttng_event_context
{
179 enum lttng_event_context_type ctx
;
180 char padding
[LTTNG_EVENT_CONTEXT_PADDING1
];
183 struct lttng_event_perf_counter_ctx perf_counter
;
184 char padding
[LTTNG_EVENT_CONTEXT_PADDING2
];
191 * Either addr is used or symbol_name and offset.
193 * The structures should be initialized to zero before use.
195 #define LTTNG_EVENT_PROBE_PADDING1 16
196 struct lttng_event_probe_attr
{
200 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
202 char padding
[LTTNG_EVENT_PROBE_PADDING1
];
208 * The structures should be initialized to zero before use.
210 #define LTTNG_EVENT_FUNCTION_PADDING1 16
211 struct lttng_event_function_attr
{
212 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
214 char padding
[LTTNG_EVENT_FUNCTION_PADDING1
];
218 * Generic lttng event
220 * The structures should be initialized to zero before use.
222 #define LTTNG_EVENT_PADDING1 15
223 #define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
225 enum lttng_event_type type
;
226 char name
[LTTNG_SYMBOL_NAME_LEN
];
228 enum lttng_loglevel_type loglevel_type
;
231 int32_t enabled
; /* Does not apply: -1 */
233 unsigned char filter
; /* filter enabled ? */
235 char padding
[LTTNG_EVENT_PADDING1
];
237 /* Per event type configuration */
239 struct lttng_event_probe_attr probe
;
240 struct lttng_event_function_attr ftrace
;
242 char padding
[LTTNG_EVENT_PADDING2
];
246 enum lttng_event_field_type
{
247 LTTNG_EVENT_FIELD_OTHER
= 0,
248 LTTNG_EVENT_FIELD_INTEGER
= 1,
249 LTTNG_EVENT_FIELD_ENUM
= 2,
250 LTTNG_EVENT_FIELD_FLOAT
= 3,
251 LTTNG_EVENT_FIELD_STRING
= 4,
254 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
255 struct lttng_event_field
{
256 char field_name
[LTTNG_SYMBOL_NAME_LEN
];
257 enum lttng_event_field_type type
;
258 char padding
[LTTNG_EVENT_FIELD_PADDING
];
259 struct lttng_event event
;
263 * Tracer channel attributes. For both kernel and user-space.
265 * The structures should be initialized to zero before use.
267 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 32
268 struct lttng_channel_attr
{
269 int overwrite
; /* 1: overwrite, 0: discard */
270 uint64_t subbuf_size
; /* bytes */
271 uint64_t num_subbuf
; /* power of 2 */
272 unsigned int switch_timer_interval
; /* usec */
273 unsigned int read_timer_interval
; /* usec */
274 enum lttng_event_output output
; /* splice, mmap */
276 char padding
[LTTNG_CHANNEL_ATTR_PADDING1
];
280 * Channel information structure. For both kernel and user-space.
282 * The structures should be initialized to zero before use.
284 #define LTTNG_CHANNEL_PADDING1 16
285 struct lttng_channel
{
286 char name
[LTTNG_SYMBOL_NAME_LEN
];
288 struct lttng_channel_attr attr
;
290 char padding
[LTTNG_CHANNEL_PADDING1
];
293 #define LTTNG_CALIBRATE_PADDING1 16
294 struct lttng_calibrate
{
295 enum lttng_calibrate_type type
;
297 char padding
[LTTNG_CALIBRATE_PADDING1
];
301 * Basic session information.
303 * This is an 'output data' meaning that it only comes *from* the session
304 * daemon *to* the lttng client. It's basically a 'human' representation of
305 * tracing entities (here a session).
307 * The structures should be initialized to zero before use.
309 #define LTTNG_SESSION_PADDING1 16
310 struct lttng_session
{
312 /* The path where traces are written */
314 uint32_t enabled
; /* enabled/started: 1, disabled/stopped: 0 */
316 char padding
[LTTNG_SESSION_PADDING1
];
320 * Handle used as a context for commands.
322 * The structures should be initialized to zero before use.
324 #define LTTNG_HANDLE_PADDING1 16
325 struct lttng_handle
{
326 char session_name
[NAME_MAX
];
327 struct lttng_domain domain
;
329 char padding
[LTTNG_HANDLE_PADDING1
];
333 * Public LTTng control API
335 * For functions having an lttng domain type as parameter, if a bad value is
336 * given, NO default is applied and an error is returned.
338 * On success, all functions of the API return 0 or the size of the allocated
341 * On error, a negative value is returned being a specific lttng-tools error
342 * code which can be humanly interpreted with lttng_strerror(err).
344 * Exceptions to this are noted below.
348 * Create a handle used as a context for every request made to the library.
350 * This handle contains the session name and lttng domain on which the command
352 * The returned pointer will be NULL in case of malloc() error.
354 extern struct lttng_handle
*lttng_create_handle(const char *session_name
,
355 struct lttng_domain
*domain
);
358 * Destroy a handle. This will simply free(3) the data pointer returned by
359 * lttng_create_handle(), rendering it unusable.
361 extern void lttng_destroy_handle(struct lttng_handle
*handle
);
364 * Create a tracing session using a name and an optional URL.
366 * If _url_ is NULL, no consumer is created for the session.
368 extern int lttng_create_session(const char *name
, const char *url
);
371 * Destroy a tracing session.
373 * The session will not be usable anymore, tracing will be stopped for all
374 * registered traces, and the tracing buffers will be flushed.
376 extern int lttng_destroy_session(const char *name
);
379 * List all the tracing sessions.
381 * Return the size (number of entries) of the "lttng_session" array. Caller
384 extern int lttng_list_sessions(struct lttng_session
**sessions
);
387 * List the registered domain(s) of a session.
389 * Return the size (number of entries) of the "lttng_domain" array. Caller
392 extern int lttng_list_domains(const char *session_name
,
393 struct lttng_domain
**domains
);
396 * List the channel(s) of a session.
398 * Return the size (number of entries) of the "lttng_channel" array. Caller
401 extern int lttng_list_channels(struct lttng_handle
*handle
,
402 struct lttng_channel
**channels
);
405 * List the event(s) of a session channel.
407 * Return the size (number of entries) of the "lttng_event" array.
408 * Caller must free(3).
410 extern int lttng_list_events(struct lttng_handle
*handle
,
411 const char *channel_name
, struct lttng_event
**events
);
414 * List the available tracepoints of a specific lttng domain.
416 * Return the size (number of entries) of the "lttng_event" array.
417 * Caller must free(3).
419 extern int lttng_list_tracepoints(struct lttng_handle
*handle
,
420 struct lttng_event
**events
);
423 * List the available tracepoints fields of a specific lttng domain.
425 * Return the size (number of entries) of the "lttng_event_field" array.
426 * Caller must free(3).
428 extern int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
429 struct lttng_event_field
**fields
);
432 * Check if a session daemon is alive.
434 * Return 1 if alive or 0 if not. On error returns a negative value.
436 extern int lttng_session_daemon_alive(void);
439 * Set the tracing group for the *current* flow of execution.
441 * On success, returns 0, on error, returns -1 (null name) or -ENOMEM.
443 extern int lttng_set_tracing_group(const char *name
);
446 * Return a human-readable error message for an lttng-tools error code.
448 * Parameter MUST be a negative value or else you'll get a generic message.
450 extern const char *lttng_strerror(int code
);
453 * This call registers an "outside consumer" for a session and an lttng domain.
454 * No consumer will be spawned and all fds/commands will go through the socket
455 * path given (socket_path).
457 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
458 * command socket. The error socket is not supported yet for roaming consumers.
460 extern int lttng_register_consumer(struct lttng_handle
*handle
,
461 const char *socket_path
);
464 * Start tracing for *all* registered traces (kernel and user-space).
466 extern int lttng_start_tracing(const char *session_name
);
469 * Stop tracing for *all* registered traces (kernel and user-space).
471 extern int lttng_stop_tracing(const char *session_name
);
474 * Add context to event(s) for a specific channel (or for all).
476 * If event_name is NULL, the context is applied to all events of the channel.
477 * If channel_name is NULL, a lookup of the event's channel is done.
478 * If both are NULL, the context is applied to all events of all channels.
480 extern int lttng_add_context(struct lttng_handle
*handle
,
481 struct lttng_event_context
*ctx
, const char *event_name
,
482 const char *channel_name
);
485 * Create or enable an event (or events) for a channel.
487 * If the event you are trying to enable does not exist, it will be created,
488 * else it is enabled.
489 * If event_name is NULL, all events are enabled.
490 * If channel_name is NULL, the default channel is used (channel0).
492 extern int lttng_enable_event(struct lttng_handle
*handle
,
493 struct lttng_event
*ev
, const char *channel_name
);
496 * Apply a filter expression to an event.
498 * If event_name is NULL, the filter is applied to all events of the channel.
499 * If channel_name is NULL, a lookup of the event's channel is done.
500 * If both are NULL, the filter is applied to all events of all channels.
502 extern int lttng_set_event_filter(struct lttng_handle
*handle
,
503 const char *event_name
,
504 const char *channel_name
,
505 const char *filter_expression
);
507 * Create or enable a channel.
508 * The channel name cannot be NULL.
510 extern int lttng_enable_channel(struct lttng_handle
*handle
,
511 struct lttng_channel
*chan
);
514 * Disable event(s) of a channel and domain.
516 * If event_name is NULL, all events are disabled.
517 * If channel_name is NULL, the default channel is used (channel0).
519 extern int lttng_disable_event(struct lttng_handle
*handle
,
520 const char *name
, const char *channel_name
);
525 * The channel name cannot be NULL.
527 extern int lttng_disable_channel(struct lttng_handle
*handle
,
531 * Calibrate LTTng overhead.
533 extern int lttng_calibrate(struct lttng_handle
*handle
,
534 struct lttng_calibrate
*calibrate
);
537 * Set the default channel attributes for a specific domain and an allocated
538 * lttng_channel_attr pointer.
540 * If either or both of the arguments are NULL, nothing happens.
542 extern void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
543 struct lttng_channel_attr
*attr
);
546 * Set URL for a consumer for a session and domain.
548 * Both data and control URL must be defined. If both URLs are the same, only
549 * the control URL is used even for network streaming.
551 * Default port are 5342 and 5343 respectively for control and data which uses
554 extern int lttng_set_consumer_url(struct lttng_handle
*handle
,
555 const char *control_url
, const char *data_url
);
558 * Enable the consumer for a session and domain.
560 extern int lttng_enable_consumer(struct lttng_handle
*handle
);
563 * Disable consumer for a session and domain.
565 extern int lttng_disable_consumer(struct lttng_handle
*handle
);
568 * Check session daemon health for a specific component.
570 * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
571 * the control library was not able to connect to the session daemon health
574 * Any other positive value is an lttcomm error which can be translate with
577 extern int lttng_health_check(enum lttng_health_component c
);