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 * Necessary to include the fixed width type limits on glibc versions older
28 * than 2.18 when building with a C++ compiler.
30 #ifndef __STDC_LIMIT_MACROS
31 #define __STDC_LIMIT_MACROS
33 #undef __STDC_LIMIT_MACROS
34 #else /* #ifndef __STDC_LIMIT_MACROS */
36 #endif /* #else #ifndef __STDC_LIMIT_MACROS */
37 #include <sys/types.h>
39 /* Error codes that can be returned by API calls */
40 #include <lttng/lttng-error.h>
47 * Event symbol length. Copied from LTTng kernel ABI.
49 #define LTTNG_SYMBOL_NAME_LEN 256
52 * Every lttng_event_* structure both apply to kernel event and user-space
57 * Domain types: the different possible tracers.
59 enum lttng_domain_type
{
60 LTTNG_DOMAIN_KERNEL
= 1,
64 * For now, the domains below are not implemented. However, we keep them
65 * here in order to retain their enum values for future development. Note
66 * that it is on the roadmap to implement them.
68 LTTNG_DOMAIN_UST_EXEC_NAME = 3,
69 LTTNG_DOMAIN_UST_PID = 4,
70 LTTNG_DOMAIN_UST_PID_FOLLOW_CHILDREN = 5,
75 * Instrumentation type of tracing event.
77 enum lttng_event_type
{
79 LTTNG_EVENT_TRACEPOINT
= 0,
80 LTTNG_EVENT_PROBE
= 1,
81 LTTNG_EVENT_FUNCTION
= 2,
82 LTTNG_EVENT_FUNCTION_ENTRY
= 3,
84 LTTNG_EVENT_SYSCALL
= 5,
88 * Loglevel information.
90 enum lttng_loglevel_type
{
91 LTTNG_EVENT_LOGLEVEL_ALL
= 0,
92 LTTNG_EVENT_LOGLEVEL_RANGE
= 1,
93 LTTNG_EVENT_LOGLEVEL_SINGLE
= 2,
97 * Available loglevels.
100 LTTNG_LOGLEVEL_EMERG
= 0,
101 LTTNG_LOGLEVEL_ALERT
= 1,
102 LTTNG_LOGLEVEL_CRIT
= 2,
103 LTTNG_LOGLEVEL_ERR
= 3,
104 LTTNG_LOGLEVEL_WARNING
= 4,
105 LTTNG_LOGLEVEL_NOTICE
= 5,
106 LTTNG_LOGLEVEL_INFO
= 6,
107 LTTNG_LOGLEVEL_DEBUG_SYSTEM
= 7,
108 LTTNG_LOGLEVEL_DEBUG_PROGRAM
= 8,
109 LTTNG_LOGLEVEL_DEBUG_PROCESS
= 9,
110 LTTNG_LOGLEVEL_DEBUG_MODULE
= 10,
111 LTTNG_LOGLEVEL_DEBUG_UNIT
= 11,
112 LTTNG_LOGLEVEL_DEBUG_FUNCTION
= 12,
113 LTTNG_LOGLEVEL_DEBUG_LINE
= 13,
114 LTTNG_LOGLEVEL_DEBUG
= 14,
118 * LTTng consumer mode
120 enum lttng_event_output
{
121 LTTNG_EVENT_SPLICE
= 0,
122 LTTNG_EVENT_MMAP
= 1,
125 /* Event context possible type */
126 enum lttng_event_context_type
{
127 LTTNG_EVENT_CONTEXT_PID
= 0,
128 LTTNG_EVENT_CONTEXT_PERF_COUNTER
= 1,
129 LTTNG_EVENT_CONTEXT_PROCNAME
= 2,
130 LTTNG_EVENT_CONTEXT_PRIO
= 3,
131 LTTNG_EVENT_CONTEXT_NICE
= 4,
132 LTTNG_EVENT_CONTEXT_VPID
= 5,
133 LTTNG_EVENT_CONTEXT_TID
= 6,
134 LTTNG_EVENT_CONTEXT_VTID
= 7,
135 LTTNG_EVENT_CONTEXT_PPID
= 8,
136 LTTNG_EVENT_CONTEXT_VPPID
= 9,
137 LTTNG_EVENT_CONTEXT_PTHREAD_ID
= 10,
138 LTTNG_EVENT_CONTEXT_HOSTNAME
= 11,
139 LTTNG_EVENT_CONTEXT_IP
= 12,
142 enum lttng_calibrate_type
{
143 LTTNG_CALIBRATE_FUNCTION
= 0,
146 /* Health component for the health check function. */
147 enum lttng_health_component
{
149 LTTNG_HEALTH_APP_MANAGE
,
150 LTTNG_HEALTH_APP_REG
,
152 LTTNG_HEALTH_CONSUMER
,
153 LTTNG_HEALTH_HT_CLEANUP
,
154 LTTNG_HEALTH_APP_MANAGE_NOTIFY
,
155 LTTNG_HEALTH_APP_REG_DISPATCH
,
159 /* Buffer type for a specific domain. */
160 enum lttng_buffer_type
{
161 LTTNG_BUFFER_PER_PID
, /* Only supported by UST being the default. */
162 LTTNG_BUFFER_PER_UID
, /* Only supported by UST. */
163 LTTNG_BUFFER_GLOBAL
, /* Only supported by the Kernel. */
167 * The structures should be initialized to zero before use.
169 #define LTTNG_DOMAIN_PADDING1 12
170 #define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
171 struct lttng_domain
{
172 enum lttng_domain_type type
;
173 enum lttng_buffer_type buf_type
;
174 char padding
[LTTNG_DOMAIN_PADDING1
];
178 char exec_name
[NAME_MAX
];
179 char padding
[LTTNG_DOMAIN_PADDING2
];
184 * Perf counter attributes
186 * The structures should be initialized to zero before use.
188 #define LTTNG_PERF_EVENT_PADDING1 16
189 struct lttng_event_perf_counter_ctx
{
192 char name
[LTTNG_SYMBOL_NAME_LEN
];
194 char padding
[LTTNG_PERF_EVENT_PADDING1
];
198 * Event/channel context
200 * The structures should be initialized to zero before use.
202 #define LTTNG_EVENT_CONTEXT_PADDING1 16
203 #define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
204 struct lttng_event_context
{
205 enum lttng_event_context_type ctx
;
206 char padding
[LTTNG_EVENT_CONTEXT_PADDING1
];
209 struct lttng_event_perf_counter_ctx perf_counter
;
210 char padding
[LTTNG_EVENT_CONTEXT_PADDING2
];
217 * Either addr is used or symbol_name and offset.
219 * The structures should be initialized to zero before use.
221 #define LTTNG_EVENT_PROBE_PADDING1 16
222 struct lttng_event_probe_attr
{
226 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
228 char padding
[LTTNG_EVENT_PROBE_PADDING1
];
234 * The structures should be initialized to zero before use.
236 #define LTTNG_EVENT_FUNCTION_PADDING1 16
237 struct lttng_event_function_attr
{
238 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
240 char padding
[LTTNG_EVENT_FUNCTION_PADDING1
];
244 * Generic lttng event
246 * The structures should be initialized to zero before use.
248 #define LTTNG_EVENT_PADDING1 15
249 #define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
251 enum lttng_event_type type
;
252 char name
[LTTNG_SYMBOL_NAME_LEN
];
254 enum lttng_loglevel_type loglevel_type
;
257 int32_t enabled
; /* Does not apply: -1 */
259 unsigned char filter
; /* filter enabled ? */
261 char padding
[LTTNG_EVENT_PADDING1
];
263 /* Per event type configuration */
265 struct lttng_event_probe_attr probe
;
266 struct lttng_event_function_attr ftrace
;
268 char padding
[LTTNG_EVENT_PADDING2
];
272 enum lttng_event_field_type
{
273 LTTNG_EVENT_FIELD_OTHER
= 0,
274 LTTNG_EVENT_FIELD_INTEGER
= 1,
275 LTTNG_EVENT_FIELD_ENUM
= 2,
276 LTTNG_EVENT_FIELD_FLOAT
= 3,
277 LTTNG_EVENT_FIELD_STRING
= 4,
280 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
281 struct lttng_event_field
{
282 char field_name
[LTTNG_SYMBOL_NAME_LEN
];
283 enum lttng_event_field_type type
;
284 char padding
[LTTNG_EVENT_FIELD_PADDING
];
285 struct lttng_event event
;
290 * Tracer channel attributes. For both kernel and user-space.
292 * The structures should be initialized to zero before use.
294 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 16
295 struct lttng_channel_attr
{
296 int overwrite
; /* 1: overwrite, 0: discard */
297 uint64_t subbuf_size
; /* bytes */
298 uint64_t num_subbuf
; /* power of 2 */
299 unsigned int switch_timer_interval
; /* usec */
300 unsigned int read_timer_interval
; /* usec */
301 enum lttng_event_output output
; /* splice, mmap */
302 /* LTTng 2.1 padding limit */
303 uint64_t tracefile_size
; /* bytes */
304 uint64_t tracefile_count
; /* number of tracefiles */
306 char padding
[LTTNG_CHANNEL_ATTR_PADDING1
];
310 * Channel information structure. For both kernel and user-space.
312 * The structures should be initialized to zero before use.
314 #define LTTNG_CHANNEL_PADDING1 16
315 struct lttng_channel
{
316 char name
[LTTNG_SYMBOL_NAME_LEN
];
318 struct lttng_channel_attr attr
;
320 char padding
[LTTNG_CHANNEL_PADDING1
];
323 #define LTTNG_CALIBRATE_PADDING1 16
324 struct lttng_calibrate
{
325 enum lttng_calibrate_type type
;
327 char padding
[LTTNG_CALIBRATE_PADDING1
];
331 * Basic session information.
333 * This is an 'output data' meaning that it only comes *from* the session
334 * daemon *to* the lttng client. It's basically a 'human' representation of
335 * tracing entities (here a session).
337 * The structures should be initialized to zero before use.
339 #define LTTNG_SESSION_PADDING1 12
340 struct lttng_session
{
342 /* The path where traces are written */
344 uint32_t enabled
; /* enabled/started: 1, disabled/stopped: 0 */
345 uint32_t snapshot_mode
;
347 char padding
[LTTNG_SESSION_PADDING1
];
351 * Handle used as a context for commands.
353 * The structures should be initialized to zero before use.
355 #define LTTNG_HANDLE_PADDING1 16
356 struct lttng_handle
{
357 char session_name
[NAME_MAX
];
358 struct lttng_domain domain
;
360 char padding
[LTTNG_HANDLE_PADDING1
];
364 * Public LTTng control API
366 * For functions having an lttng domain type as parameter, if a bad value is
367 * given, NO default is applied and an error is returned.
369 * On success, all functions of the API return 0 or the size of the allocated
372 * On error, a negative value is returned being a specific lttng-tools error
373 * code which can be humanly interpreted with lttng_strerror(err).
375 * Exceptions to this are noted below.
379 * Create a handle used as a context for every request made to the library.
381 * This handle contains the session name and lttng domain on which the command
383 * The returned pointer will be NULL in case of malloc() error.
385 extern struct lttng_handle
*lttng_create_handle(const char *session_name
,
386 struct lttng_domain
*domain
);
391 * It free(3) the data pointer returned by lttng_create_handle(), rendering it
394 extern void lttng_destroy_handle(struct lttng_handle
*handle
);
397 * Create a tracing session using a name and an optional URL.
399 * If _url_ is NULL, no consumer is created for the session. The name can't be
402 extern int lttng_create_session(const char *name
, const char *url
);
405 * Create a tracing session that will exclusively be used for snapshot meaning
406 * the session will be in no output mode and every channel enabled for that
407 * session will be set in overwrite mode and in mmap output since splice is not
410 * If an url is given, it will be used to create a default snapshot output
411 * using it as a destination. If NULL, no output will be defined and an
412 * add-output call will be needed.
414 * Name can't be NULL.
416 extern int lttng_create_session_snapshot(const char *name
,
417 const char *snapshot_url
);
420 * Destroy a tracing session.
422 * The session will not be usable anymore, tracing will be stopped for all
423 * registered traces, and the tracing buffers will be flushed.
425 * The name can't be NULL here.
427 extern int lttng_destroy_session(const char *name
);
430 * List all the tracing sessions.
432 * Return the size (number of entries) of the "lttng_session" array. Caller
435 extern int lttng_list_sessions(struct lttng_session
**sessions
);
438 * List the registered domain(s) of a session.
440 * Return the size (number of entries) of the "lttng_domain" array. Caller
443 extern int lttng_list_domains(const char *session_name
,
444 struct lttng_domain
**domains
);
447 * List the channel(s) of a session.
449 * Return the size (number of entries) of the "lttng_channel" array. Caller
452 extern int lttng_list_channels(struct lttng_handle
*handle
,
453 struct lttng_channel
**channels
);
456 * List the event(s) of a session channel.
458 * Return the size (number of entries) of the "lttng_event" array.
459 * Caller must free(3).
461 extern int lttng_list_events(struct lttng_handle
*handle
,
462 const char *channel_name
, struct lttng_event
**events
);
465 * List the available tracepoints of a specific lttng domain.
467 * Return the size (number of entries) of the "lttng_event" array.
468 * Caller must free(3).
470 extern int lttng_list_tracepoints(struct lttng_handle
*handle
,
471 struct lttng_event
**events
);
474 * List the available tracepoints fields of a specific lttng domain.
476 * Return the size (number of entries) of the "lttng_event_field" array.
477 * Caller must free(3).
479 extern int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
480 struct lttng_event_field
**fields
);
483 * Check if a session daemon is alive.
485 * Return 1 if alive or 0 if not. On error returns a negative value.
487 extern int lttng_session_daemon_alive(void);
490 * Set the tracing group for the *current* flow of execution.
492 * On success, returns 0 else a negative value on error being a lttng error
493 * code found in lttng-error.h
495 extern int lttng_set_tracing_group(const char *name
);
498 * Return a human-readable error message for an lttng-tools error code.
500 * Parameter MUST be a negative value or else you'll get a generic message.
502 extern const char *lttng_strerror(int code
);
505 * This call registers an "outside consumer" for a session and an lttng domain.
506 * No consumer will be spawned and all fds/commands will go through the socket
507 * path given (socket_path).
509 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
510 * command socket. The error socket is not supported yet for roaming consumers.
512 extern int lttng_register_consumer(struct lttng_handle
*handle
,
513 const char *socket_path
);
516 * Start tracing for *all* registered traces (kernel and user-space).
518 extern int lttng_start_tracing(const char *session_name
);
521 * Stop tracing for *all* registered traces (kernel and user-space).
523 * This call will wait for data availability for each domain of the session so
524 * this can take an abritrary amount of time. However, when returning you have
525 * the guarantee that the data is ready to be read and analyse. Use the
526 * _no_wait call below to avoid this behavior.
528 * The session_name can't be NULL.
530 extern int lttng_stop_tracing(const char *session_name
);
533 * Behave exactly like lttng_stop_tracing but does not wait for data
536 extern int lttng_stop_tracing_no_wait(const char *session_name
);
539 * Add context to event(s) for a specific channel (or for all).
541 * If channel_name is NULL, a lookup of the event's channel is done. If both
542 * are NULL, the context is applied to all events of all channels.
544 * Note that whatever event_name value is, a context can not be added to an
545 * event, so we just ignore it for now.
547 extern int lttng_add_context(struct lttng_handle
*handle
,
548 struct lttng_event_context
*ctx
, const char *event_name
,
549 const char *channel_name
);
552 * Create or enable an event (or events) for a channel.
554 * If the event you are trying to enable does not exist, it will be created,
555 * else it is enabled.
556 * If channel_name is NULL, the default channel is used (channel0).
558 * The handle and ev params can not be NULL.
560 extern int lttng_enable_event(struct lttng_handle
*handle
,
561 struct lttng_event
*ev
, const char *channel_name
);
564 * Create or enable an event with a specific filter.
566 * If the event you are trying to enable does not exist, it will be created,
567 * else it is enabled.
568 * If ev is NULL, all events are enabled with that filter.
569 * If channel_name is NULL, the default channel is used (channel0) and created
571 * If filter_expression is NULL, an event without associated filter is
574 extern int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
575 struct lttng_event
*event
, const char *channel_name
,
576 const char *filter_expression
);
579 * Create or enable a channel.
581 * The chan and handle params can not be NULL.
583 extern int lttng_enable_channel(struct lttng_handle
*handle
,
584 struct lttng_channel
*chan
);
587 * Disable event(s) of a channel and domain.
589 * If name is NULL, all events are disabled.
590 * If channel_name is NULL, the default channel is used (channel0).
592 extern int lttng_disable_event(struct lttng_handle
*handle
,
593 const char *name
, const char *channel_name
);
599 extern int lttng_disable_channel(struct lttng_handle
*handle
,
603 * Calibrate LTTng overhead.
605 * The chan and handle params can not be NULL.
607 extern int lttng_calibrate(struct lttng_handle
*handle
,
608 struct lttng_calibrate
*calibrate
);
611 * Set the default channel attributes for a specific domain and an allocated
612 * lttng_channel_attr pointer.
614 * If one or both arguments are NULL, nothing happens.
616 extern void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
617 struct lttng_channel_attr
*attr
);
620 * Set URL for a consumer for a session and domain.
622 * Both data and control URL must be defined. If both URLs are the same, only
623 * the control URL is used even for network streaming.
625 * Default port are 5342 and 5343 respectively for control and data which uses
628 extern int lttng_set_consumer_url(struct lttng_handle
*handle
,
629 const char *control_url
, const char *data_url
);
632 * Enable the consumer for a session and domain.
634 extern LTTNG_DEPRECATED("This call is now obsolete.")
635 int lttng_enable_consumer(struct lttng_handle
*handle
);
638 * Disable consumer for a session and domain.
640 extern LTTNG_DEPRECATED("This call is now obsolete.")
641 int lttng_disable_consumer(struct lttng_handle
*handle
);
644 * Check session daemon health for a specific component.
646 * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
647 * the control library was not able to connect to the session daemon health
650 * Any other positive value is an lttcomm error which can be translate with
653 * Please see lttng-health-check(3) man page for more information.
655 extern int lttng_health_check(enum lttng_health_component c
);
658 * For a given session name, this call checks if the data is ready to be read
659 * or is still being extracted by the consumer(s) (pending) hence not ready to
660 * be used by any readers.
662 * Return 0 if there is _no_ data pending in the buffers thus having a
663 * guarantee that the data can be read safely. Else, return 1 if there is still
664 * traced data is pending. On error, a negative value is returned and readable
665 * by lttng_strerror().
667 extern int lttng_data_pending(const char *session_name
);