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, /* Linux Kernel tracer. */
51 LTTNG_DOMAIN_UST
= 2, /* Global Userspace tracer. */
52 LTTNG_DOMAIN_JUL
= 3, /* Java Util Logging. */
56 * Instrumentation type of tracing event.
58 enum lttng_event_type
{
60 LTTNG_EVENT_TRACEPOINT
= 0,
61 LTTNG_EVENT_PROBE
= 1,
62 LTTNG_EVENT_FUNCTION
= 2,
63 LTTNG_EVENT_FUNCTION_ENTRY
= 3,
65 LTTNG_EVENT_SYSCALL
= 5,
69 * Loglevel information.
71 enum lttng_loglevel_type
{
72 LTTNG_EVENT_LOGLEVEL_ALL
= 0,
73 LTTNG_EVENT_LOGLEVEL_RANGE
= 1,
74 LTTNG_EVENT_LOGLEVEL_SINGLE
= 2,
78 * Available loglevels.
81 LTTNG_LOGLEVEL_EMERG
= 0,
82 LTTNG_LOGLEVEL_ALERT
= 1,
83 LTTNG_LOGLEVEL_CRIT
= 2,
84 LTTNG_LOGLEVEL_ERR
= 3,
85 LTTNG_LOGLEVEL_WARNING
= 4,
86 LTTNG_LOGLEVEL_NOTICE
= 5,
87 LTTNG_LOGLEVEL_INFO
= 6,
88 LTTNG_LOGLEVEL_DEBUG_SYSTEM
= 7,
89 LTTNG_LOGLEVEL_DEBUG_PROGRAM
= 8,
90 LTTNG_LOGLEVEL_DEBUG_PROCESS
= 9,
91 LTTNG_LOGLEVEL_DEBUG_MODULE
= 10,
92 LTTNG_LOGLEVEL_DEBUG_UNIT
= 11,
93 LTTNG_LOGLEVEL_DEBUG_FUNCTION
= 12,
94 LTTNG_LOGLEVEL_DEBUG_LINE
= 13,
95 LTTNG_LOGLEVEL_DEBUG
= 14,
101 enum lttng_event_output
{
102 LTTNG_EVENT_SPLICE
= 0,
103 LTTNG_EVENT_MMAP
= 1,
106 /* Event context possible type */
107 enum lttng_event_context_type
{
108 LTTNG_EVENT_CONTEXT_PID
= 0,
109 LTTNG_EVENT_CONTEXT_PERF_COUNTER
= 1,
110 LTTNG_EVENT_CONTEXT_PROCNAME
= 2,
111 LTTNG_EVENT_CONTEXT_PRIO
= 3,
112 LTTNG_EVENT_CONTEXT_NICE
= 4,
113 LTTNG_EVENT_CONTEXT_VPID
= 5,
114 LTTNG_EVENT_CONTEXT_TID
= 6,
115 LTTNG_EVENT_CONTEXT_VTID
= 7,
116 LTTNG_EVENT_CONTEXT_PPID
= 8,
117 LTTNG_EVENT_CONTEXT_VPPID
= 9,
118 LTTNG_EVENT_CONTEXT_PTHREAD_ID
= 10,
119 LTTNG_EVENT_CONTEXT_HOSTNAME
= 11,
120 LTTNG_EVENT_CONTEXT_IP
= 12,
123 enum lttng_calibrate_type
{
124 LTTNG_CALIBRATE_FUNCTION
= 0,
127 /* Health component for the health check function. */
128 enum lttng_health_component
{
130 LTTNG_HEALTH_APP_MANAGE
,
131 LTTNG_HEALTH_APP_REG
,
133 LTTNG_HEALTH_CONSUMER
,
134 LTTNG_HEALTH_HT_CLEANUP
,
135 LTTNG_HEALTH_APP_MANAGE_NOTIFY
,
136 LTTNG_HEALTH_APP_REG_DISPATCH
,
140 /* Buffer type for a specific domain. */
141 enum lttng_buffer_type
{
142 LTTNG_BUFFER_PER_PID
, /* Only supported by UST being the default. */
143 LTTNG_BUFFER_PER_UID
, /* Only supported by UST. */
144 LTTNG_BUFFER_GLOBAL
, /* Only supported by the Kernel. */
148 * The structures should be initialized to zero before use.
150 #define LTTNG_DOMAIN_PADDING1 12
151 #define LTTNG_DOMAIN_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
152 struct lttng_domain
{
153 enum lttng_domain_type type
;
154 enum lttng_buffer_type buf_type
;
155 char padding
[LTTNG_DOMAIN_PADDING1
];
159 char exec_name
[NAME_MAX
];
160 char padding
[LTTNG_DOMAIN_PADDING2
];
165 * Perf counter attributes
167 * The structures should be initialized to zero before use.
169 #define LTTNG_PERF_EVENT_PADDING1 16
170 struct lttng_event_perf_counter_ctx
{
173 char name
[LTTNG_SYMBOL_NAME_LEN
];
175 char padding
[LTTNG_PERF_EVENT_PADDING1
];
179 * Event/channel context
181 * The structures should be initialized to zero before use.
183 #define LTTNG_EVENT_CONTEXT_PADDING1 16
184 #define LTTNG_EVENT_CONTEXT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
185 struct lttng_event_context
{
186 enum lttng_event_context_type ctx
;
187 char padding
[LTTNG_EVENT_CONTEXT_PADDING1
];
190 struct lttng_event_perf_counter_ctx perf_counter
;
191 char padding
[LTTNG_EVENT_CONTEXT_PADDING2
];
198 * Either addr is used or symbol_name and offset.
200 * The structures should be initialized to zero before use.
202 #define LTTNG_EVENT_PROBE_PADDING1 16
203 struct lttng_event_probe_attr
{
207 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
209 char padding
[LTTNG_EVENT_PROBE_PADDING1
];
215 * The structures should be initialized to zero before use.
217 #define LTTNG_EVENT_FUNCTION_PADDING1 16
218 struct lttng_event_function_attr
{
219 char symbol_name
[LTTNG_SYMBOL_NAME_LEN
];
221 char padding
[LTTNG_EVENT_FUNCTION_PADDING1
];
225 * Generic lttng event
227 * The structures should be initialized to zero before use.
229 #define LTTNG_EVENT_PADDING1 14
230 #define LTTNG_EVENT_PADDING2 LTTNG_SYMBOL_NAME_LEN + 32
232 enum lttng_event_type type
;
233 char name
[LTTNG_SYMBOL_NAME_LEN
];
235 enum lttng_loglevel_type loglevel_type
;
238 int32_t enabled
; /* Does not apply: -1 */
240 unsigned char filter
; /* filter enabled ? */
241 unsigned char exclusion
; /* exclusions added ? */
243 char padding
[LTTNG_EVENT_PADDING1
];
245 /* Per event type configuration */
247 struct lttng_event_probe_attr probe
;
248 struct lttng_event_function_attr ftrace
;
250 char padding
[LTTNG_EVENT_PADDING2
];
254 enum lttng_event_field_type
{
255 LTTNG_EVENT_FIELD_OTHER
= 0,
256 LTTNG_EVENT_FIELD_INTEGER
= 1,
257 LTTNG_EVENT_FIELD_ENUM
= 2,
258 LTTNG_EVENT_FIELD_FLOAT
= 3,
259 LTTNG_EVENT_FIELD_STRING
= 4,
262 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
263 struct lttng_event_field
{
264 char field_name
[LTTNG_SYMBOL_NAME_LEN
];
265 enum lttng_event_field_type type
;
266 char padding
[LTTNG_EVENT_FIELD_PADDING
];
267 struct lttng_event event
;
272 * Tracer channel attributes. For both kernel and user-space.
274 * The structures should be initialized to zero before use.
276 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 12
277 struct lttng_channel_attr
{
278 int overwrite
; /* 1: overwrite, 0: discard */
279 uint64_t subbuf_size
; /* bytes */
280 uint64_t num_subbuf
; /* power of 2 */
281 unsigned int switch_timer_interval
; /* usec */
282 unsigned int read_timer_interval
; /* usec */
283 enum lttng_event_output output
; /* splice, mmap */
284 /* LTTng 2.1 padding limit */
285 uint64_t tracefile_size
; /* bytes */
286 uint64_t tracefile_count
; /* number of tracefiles */
287 /* LTTng 2.3 padding limit */
288 unsigned int live_timer_interval
; /* usec */
290 char padding
[LTTNG_CHANNEL_ATTR_PADDING1
];
294 * Channel information structure. For both kernel and user-space.
296 * The structures should be initialized to zero before use.
298 #define LTTNG_CHANNEL_PADDING1 16
299 struct lttng_channel
{
300 char name
[LTTNG_SYMBOL_NAME_LEN
];
302 struct lttng_channel_attr attr
;
304 char padding
[LTTNG_CHANNEL_PADDING1
];
307 #define LTTNG_CALIBRATE_PADDING1 16
308 struct lttng_calibrate
{
309 enum lttng_calibrate_type type
;
311 char padding
[LTTNG_CALIBRATE_PADDING1
];
315 * Basic session information.
317 * This is an 'output data' meaning that it only comes *from* the session
318 * daemon *to* the lttng client. It's basically a 'human' representation of
319 * tracing entities (here a session).
321 * The structures should be initialized to zero before use.
323 #define LTTNG_SESSION_PADDING1 12
324 struct lttng_session
{
326 /* The path where traces are written */
328 uint32_t enabled
; /* enabled/started: 1, disabled/stopped: 0 */
329 uint32_t snapshot_mode
;
330 unsigned int live_timer_interval
; /* usec */
332 char padding
[LTTNG_SESSION_PADDING1
];
336 * Handle used as a context for commands.
338 * The structures should be initialized to zero before use.
340 #define LTTNG_HANDLE_PADDING1 16
341 struct lttng_handle
{
342 char session_name
[NAME_MAX
];
343 struct lttng_domain domain
;
345 char padding
[LTTNG_HANDLE_PADDING1
];
349 * Public LTTng control API
351 * For functions having an lttng domain type as parameter, if a bad value is
352 * given, NO default is applied and an error is returned.
354 * On success, all functions of the API return 0 or the size of the allocated
357 * On error, a negative value is returned being a specific lttng-tools error
358 * code which can be humanly interpreted with lttng_strerror(err).
360 * Exceptions to this are noted below.
364 * Create a handle used as a context for every request made to the library.
366 * This handle contains the session name and lttng domain on which the command
368 * The returned pointer will be NULL in case of malloc() error.
370 extern struct lttng_handle
*lttng_create_handle(const char *session_name
,
371 struct lttng_domain
*domain
);
376 * It free(3) the data pointer returned by lttng_create_handle(), rendering it
379 extern void lttng_destroy_handle(struct lttng_handle
*handle
);
382 * Create a tracing session using a name and an optional URL.
384 * If _url_ is NULL, no consumer is created for the session. The name can't be
387 extern int lttng_create_session(const char *name
, const char *url
);
390 * Create a tracing session that will exclusively be used for snapshot meaning
391 * the session will be in no output mode and every channel enabled for that
392 * session will be set in overwrite mode and in mmap output since splice is not
395 * If an url is given, it will be used to create a default snapshot output
396 * using it as a destination. If NULL, no output will be defined and an
397 * add-output call will be needed.
399 * Name can't be NULL.
401 extern int lttng_create_session_snapshot(const char *name
,
402 const char *snapshot_url
);
405 * Create a session exclusively used for live reading.
407 * In this mode, the switch-timer parameter is forced for each UST channel, a
408 * live-switch-timer is enabled for kernel channels, manually setting
409 * switch-timer is forbidden. Synchronization beacons are sent to the relayd,
410 * indexes are sent and metadata is checked for each packet.
412 * Returns LTTNG_OK on success or a negative error code.
414 extern int lttng_create_session_live(const char *name
, const char *url
,
415 unsigned int timer_interval
);
418 * Destroy a tracing session.
420 * The session will not be usable anymore, tracing will be stopped for all
421 * registered traces, and the tracing buffers will be flushed.
423 * The name can't be NULL here.
425 extern int lttng_destroy_session(const char *name
);
428 * List all the tracing sessions.
430 * Return the size (number of entries) of the "lttng_session" array. Caller
433 extern int lttng_list_sessions(struct lttng_session
**sessions
);
436 * List the registered domain(s) of a session.
438 * Return the size (number of entries) of the "lttng_domain" array. Caller
441 extern int lttng_list_domains(const char *session_name
,
442 struct lttng_domain
**domains
);
445 * List the channel(s) of a session.
447 * Return the size (number of entries) of the "lttng_channel" array. Caller
450 extern int lttng_list_channels(struct lttng_handle
*handle
,
451 struct lttng_channel
**channels
);
454 * List the event(s) of a session channel.
456 * Return the size (number of entries) of the "lttng_event" array.
457 * Caller must free(3).
459 extern int lttng_list_events(struct lttng_handle
*handle
,
460 const char *channel_name
, struct lttng_event
**events
);
463 * List the available tracepoints of a specific lttng domain.
465 * Return the size (number of entries) of the "lttng_event" array.
466 * Caller must free(3).
468 extern int lttng_list_tracepoints(struct lttng_handle
*handle
,
469 struct lttng_event
**events
);
472 * List the available tracepoints fields of a specific lttng domain.
474 * Return the size (number of entries) of the "lttng_event_field" array.
475 * Caller must free(3).
477 extern int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
478 struct lttng_event_field
**fields
);
481 * Check if a session daemon is alive.
483 * Return 1 if alive or 0 if not. On error returns a negative value.
485 extern int lttng_session_daemon_alive(void);
488 * Set the tracing group for the *current* flow of execution.
490 * On success, returns 0 else a negative value on error being a lttng error
491 * code found in lttng-error.h
493 extern int lttng_set_tracing_group(const char *name
);
496 * Return a human-readable error message for an lttng-tools error code.
498 * Parameter MUST be a negative value or else you'll get a generic message.
500 extern const char *lttng_strerror(int code
);
503 * This call registers an "outside consumer" for a session and an lttng domain.
504 * No consumer will be spawned and all fds/commands will go through the socket
505 * path given (socket_path).
507 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
508 * command socket. The error socket is not supported yet for roaming consumers.
510 extern int lttng_register_consumer(struct lttng_handle
*handle
,
511 const char *socket_path
);
514 * Start tracing for *all* registered traces (kernel and user-space).
516 extern int lttng_start_tracing(const char *session_name
);
519 * Stop tracing for *all* registered traces (kernel and user-space).
521 * This call will wait for data availability for each domain of the session so
522 * this can take an abritrary amount of time. However, when returning you have
523 * the guarantee that the data is ready to be read and analyse. Use the
524 * _no_wait call below to avoid this behavior.
526 * The session_name can't be NULL.
528 extern int lttng_stop_tracing(const char *session_name
);
531 * Behave exactly like lttng_stop_tracing but does not wait for data
534 extern int lttng_stop_tracing_no_wait(const char *session_name
);
537 * Add context to event(s) for a specific channel (or for all).
539 * If channel_name is NULL, a lookup of the event's channel is done. If both
540 * are NULL, the context is applied to all events of all channels.
542 * Note that whatever event_name value is, a context can not be added to an
543 * event, so we just ignore it for now.
545 extern int lttng_add_context(struct lttng_handle
*handle
,
546 struct lttng_event_context
*ctx
, const char *event_name
,
547 const char *channel_name
);
550 * Create or enable an event (or events) for a channel.
552 * If the event you are trying to enable does not exist, it will be created,
553 * else it is enabled.
554 * If channel_name is NULL, the default channel is used (channel0).
556 * The handle and ev params can not be NULL.
558 extern int lttng_enable_event(struct lttng_handle
*handle
,
559 struct lttng_event
*ev
, const char *channel_name
);
562 * Create or enable an event with a specific filter.
564 * If the event you are trying to enable does not exist, it will be created,
565 * else it is enabled.
566 * If ev is NULL, all events are enabled with that filter.
567 * If channel_name is NULL, the default channel is used (channel0) and created
569 * If filter_expression is NULL, an event without associated filter is
572 extern int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
573 struct lttng_event
*event
, const char *channel_name
,
574 const char *filter_expression
);
577 * Create or enable an event with a filter and/or exclusions.
579 * If the event you are trying to enable does not exist, it will be created,
580 * else it is enabled.
581 * If ev is NULL, all events are enabled with the filter and exclusion options.
582 * If channel_name is NULL, the default channel is used (channel0) and created
584 * If filter_expression is NULL, an event without associated filter is
586 * If exclusion count is zero, the event will be created without exclusions.
588 extern int lttng_enable_event_with_exclusions(struct lttng_handle
*handle
,
589 struct lttng_event
*event
, const char *channel_name
,
590 const char *filter_expression
,
591 int exclusion_count
, char **exclusion_names
);
594 * Create or enable a channel.
596 * The chan and handle params can not be NULL.
598 extern int lttng_enable_channel(struct lttng_handle
*handle
,
599 struct lttng_channel
*chan
);
602 * Disable event(s) of a channel and domain.
604 * If name is NULL, all events are disabled.
605 * If channel_name is NULL, the default channel is used (channel0).
607 extern int lttng_disable_event(struct lttng_handle
*handle
,
608 const char *name
, const char *channel_name
);
614 extern int lttng_disable_channel(struct lttng_handle
*handle
,
618 * Calibrate LTTng overhead.
620 * The chan and handle params can not be NULL.
622 extern int lttng_calibrate(struct lttng_handle
*handle
,
623 struct lttng_calibrate
*calibrate
);
626 * Set the default channel attributes for a specific domain and an allocated
627 * lttng_channel_attr pointer.
629 * If one or both arguments are NULL, nothing happens.
631 extern void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
632 struct lttng_channel_attr
*attr
);
635 * Set URL for a consumer for a session and domain.
637 * Both data and control URL must be defined. If both URLs are the same, only
638 * the control URL is used even for network streaming.
640 * Default port are 5342 and 5343 respectively for control and data which uses
643 extern int lttng_set_consumer_url(struct lttng_handle
*handle
,
644 const char *control_url
, const char *data_url
);
647 * Enable the consumer for a session and domain.
649 extern LTTNG_DEPRECATED("This call is now obsolete.")
650 int lttng_enable_consumer(struct lttng_handle
*handle
);
653 * Disable consumer for a session and domain.
655 extern LTTNG_DEPRECATED("This call is now obsolete.")
656 int lttng_disable_consumer(struct lttng_handle
*handle
);
659 * Check session daemon health for a specific component.
661 * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
662 * the control library was not able to connect to the session daemon health
665 * Any other positive value is an lttcomm error which can be translate with
668 * Please see lttng-health-check(3) man page for more information.
670 extern LTTNG_DEPRECATED("This call is now obsolete.")
671 int lttng_health_check(enum lttng_health_component c
);
674 * For a given session name, this call checks if the data is ready to be read
675 * or is still being extracted by the consumer(s) (pending) hence not ready to
676 * be used by any readers.
678 * Return 0 if there is _no_ data pending in the buffers thus having a
679 * guarantee that the data can be read safely. Else, return 1 if there is still
680 * traced data is pending. On error, a negative value is returned and readable
681 * by lttng_strerror().
683 extern int lttng_data_pending(const char *session_name
);