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 15
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 ? */
242 char padding
[LTTNG_EVENT_PADDING1
];
244 /* Per event type configuration */
246 struct lttng_event_probe_attr probe
;
247 struct lttng_event_function_attr ftrace
;
249 char padding
[LTTNG_EVENT_PADDING2
];
253 enum lttng_event_field_type
{
254 LTTNG_EVENT_FIELD_OTHER
= 0,
255 LTTNG_EVENT_FIELD_INTEGER
= 1,
256 LTTNG_EVENT_FIELD_ENUM
= 2,
257 LTTNG_EVENT_FIELD_FLOAT
= 3,
258 LTTNG_EVENT_FIELD_STRING
= 4,
261 #define LTTNG_EVENT_FIELD_PADDING LTTNG_SYMBOL_NAME_LEN + 32
262 struct lttng_event_field
{
263 char field_name
[LTTNG_SYMBOL_NAME_LEN
];
264 enum lttng_event_field_type type
;
265 char padding
[LTTNG_EVENT_FIELD_PADDING
];
266 struct lttng_event event
;
271 * Tracer channel attributes. For both kernel and user-space.
273 * The structures should be initialized to zero before use.
275 #define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 12
276 struct lttng_channel_attr
{
277 int overwrite
; /* 1: overwrite, 0: discard */
278 uint64_t subbuf_size
; /* bytes */
279 uint64_t num_subbuf
; /* power of 2 */
280 unsigned int switch_timer_interval
; /* usec */
281 unsigned int read_timer_interval
; /* usec */
282 enum lttng_event_output output
; /* splice, mmap */
283 /* LTTng 2.1 padding limit */
284 uint64_t tracefile_size
; /* bytes */
285 uint64_t tracefile_count
; /* number of tracefiles */
286 /* LTTng 2.3 padding limit */
287 unsigned int live_timer_interval
; /* usec */
289 char padding
[LTTNG_CHANNEL_ATTR_PADDING1
];
293 * Channel information structure. For both kernel and user-space.
295 * The structures should be initialized to zero before use.
297 #define LTTNG_CHANNEL_PADDING1 16
298 struct lttng_channel
{
299 char name
[LTTNG_SYMBOL_NAME_LEN
];
301 struct lttng_channel_attr attr
;
303 char padding
[LTTNG_CHANNEL_PADDING1
];
306 #define LTTNG_CALIBRATE_PADDING1 16
307 struct lttng_calibrate
{
308 enum lttng_calibrate_type type
;
310 char padding
[LTTNG_CALIBRATE_PADDING1
];
314 * Basic session information.
316 * This is an 'output data' meaning that it only comes *from* the session
317 * daemon *to* the lttng client. It's basically a 'human' representation of
318 * tracing entities (here a session).
320 * The structures should be initialized to zero before use.
322 #define LTTNG_SESSION_PADDING1 12
323 struct lttng_session
{
325 /* The path where traces are written */
327 uint32_t enabled
; /* enabled/started: 1, disabled/stopped: 0 */
328 uint32_t snapshot_mode
;
329 unsigned int live_timer_interval
; /* usec */
331 char padding
[LTTNG_SESSION_PADDING1
];
335 * Handle used as a context for commands.
337 * The structures should be initialized to zero before use.
339 #define LTTNG_HANDLE_PADDING1 16
340 struct lttng_handle
{
341 char session_name
[NAME_MAX
];
342 struct lttng_domain domain
;
344 char padding
[LTTNG_HANDLE_PADDING1
];
348 * Public LTTng control API
350 * For functions having an lttng domain type as parameter, if a bad value is
351 * given, NO default is applied and an error is returned.
353 * On success, all functions of the API return 0 or the size of the allocated
356 * On error, a negative value is returned being a specific lttng-tools error
357 * code which can be humanly interpreted with lttng_strerror(err).
359 * Exceptions to this are noted below.
363 * Create a handle used as a context for every request made to the library.
365 * This handle contains the session name and lttng domain on which the command
367 * The returned pointer will be NULL in case of malloc() error.
369 extern struct lttng_handle
*lttng_create_handle(const char *session_name
,
370 struct lttng_domain
*domain
);
375 * It free(3) the data pointer returned by lttng_create_handle(), rendering it
378 extern void lttng_destroy_handle(struct lttng_handle
*handle
);
381 * Create a tracing session using a name and an optional URL.
383 * If _url_ is NULL, no consumer is created for the session. The name can't be
386 extern int lttng_create_session(const char *name
, const char *url
);
389 * Create a tracing session that will exclusively be used for snapshot meaning
390 * the session will be in no output mode and every channel enabled for that
391 * session will be set in overwrite mode and in mmap output since splice is not
394 * If an url is given, it will be used to create a default snapshot output
395 * using it as a destination. If NULL, no output will be defined and an
396 * add-output call will be needed.
398 * Name can't be NULL.
400 extern int lttng_create_session_snapshot(const char *name
,
401 const char *snapshot_url
);
404 * Create a session exclusively used for live reading.
406 * In this mode, the switch-timer parameter is forced for each UST channel, a
407 * live-switch-timer is enabled for kernel channels, manually setting
408 * switch-timer is forbidden. Synchronization beacons are sent to the relayd,
409 * indexes are sent and metadata is checked for each packet.
411 * Returns LTTNG_OK on success or a negative error code.
413 extern int lttng_create_session_live(const char *name
, const char *url
,
414 unsigned int timer_interval
);
417 * Destroy a tracing session.
419 * The session will not be usable anymore, tracing will be stopped for all
420 * registered traces, and the tracing buffers will be flushed.
422 * The name can't be NULL here.
424 extern int lttng_destroy_session(const char *name
);
427 * List all the tracing sessions.
429 * Return the size (number of entries) of the "lttng_session" array. Caller
432 extern int lttng_list_sessions(struct lttng_session
**sessions
);
435 * List the registered domain(s) of a session.
437 * Return the size (number of entries) of the "lttng_domain" array. Caller
440 extern int lttng_list_domains(const char *session_name
,
441 struct lttng_domain
**domains
);
444 * List the channel(s) of a session.
446 * Return the size (number of entries) of the "lttng_channel" array. Caller
449 extern int lttng_list_channels(struct lttng_handle
*handle
,
450 struct lttng_channel
**channels
);
453 * List the event(s) of a session channel.
455 * Return the size (number of entries) of the "lttng_event" array.
456 * Caller must free(3).
458 extern int lttng_list_events(struct lttng_handle
*handle
,
459 const char *channel_name
, struct lttng_event
**events
);
462 * List the available tracepoints of a specific lttng domain.
464 * Return the size (number of entries) of the "lttng_event" array.
465 * Caller must free(3).
467 extern int lttng_list_tracepoints(struct lttng_handle
*handle
,
468 struct lttng_event
**events
);
471 * List the available tracepoints fields of a specific lttng domain.
473 * Return the size (number of entries) of the "lttng_event_field" array.
474 * Caller must free(3).
476 extern int lttng_list_tracepoint_fields(struct lttng_handle
*handle
,
477 struct lttng_event_field
**fields
);
480 * Check if a session daemon is alive.
482 * Return 1 if alive or 0 if not. On error returns a negative value.
484 extern int lttng_session_daemon_alive(void);
487 * Set the tracing group for the *current* flow of execution.
489 * On success, returns 0 else a negative value on error being a lttng error
490 * code found in lttng-error.h
492 extern int lttng_set_tracing_group(const char *name
);
495 * Return a human-readable error message for an lttng-tools error code.
497 * Parameter MUST be a negative value or else you'll get a generic message.
499 extern const char *lttng_strerror(int code
);
502 * This call registers an "outside consumer" for a session and an lttng domain.
503 * No consumer will be spawned and all fds/commands will go through the socket
504 * path given (socket_path).
506 * NOTE: At the moment, if you use the liblttng-kconsumer, you can only use the
507 * command socket. The error socket is not supported yet for roaming consumers.
509 extern int lttng_register_consumer(struct lttng_handle
*handle
,
510 const char *socket_path
);
513 * Start tracing for *all* registered traces (kernel and user-space).
515 extern int lttng_start_tracing(const char *session_name
);
518 * Stop tracing for *all* registered traces (kernel and user-space).
520 * This call will wait for data availability for each domain of the session so
521 * this can take an abritrary amount of time. However, when returning you have
522 * the guarantee that the data is ready to be read and analyse. Use the
523 * _no_wait call below to avoid this behavior.
525 * The session_name can't be NULL.
527 extern int lttng_stop_tracing(const char *session_name
);
530 * Behave exactly like lttng_stop_tracing but does not wait for data
533 extern int lttng_stop_tracing_no_wait(const char *session_name
);
536 * Add context to event(s) for a specific channel (or for all).
538 * If channel_name is NULL, a lookup of the event's channel is done. If both
539 * are NULL, the context is applied to all events of all channels.
541 * Note that whatever event_name value is, a context can not be added to an
542 * event, so we just ignore it for now.
544 extern int lttng_add_context(struct lttng_handle
*handle
,
545 struct lttng_event_context
*ctx
, const char *event_name
,
546 const char *channel_name
);
549 * Create or enable an event (or events) for a channel.
551 * If the event you are trying to enable does not exist, it will be created,
552 * else it is enabled.
553 * If channel_name is NULL, the default channel is used (channel0).
555 * The handle and ev params can not be NULL.
557 extern int lttng_enable_event(struct lttng_handle
*handle
,
558 struct lttng_event
*ev
, const char *channel_name
);
561 * Create or enable an event with a specific filter.
563 * If the event you are trying to enable does not exist, it will be created,
564 * else it is enabled.
565 * If ev is NULL, all events are enabled with that filter.
566 * If channel_name is NULL, the default channel is used (channel0) and created
568 * If filter_expression is NULL, an event without associated filter is
571 extern int lttng_enable_event_with_filter(struct lttng_handle
*handle
,
572 struct lttng_event
*event
, const char *channel_name
,
573 const char *filter_expression
);
576 * Create or enable a channel.
578 * The chan and handle params can not be NULL.
580 extern int lttng_enable_channel(struct lttng_handle
*handle
,
581 struct lttng_channel
*chan
);
584 * Disable event(s) of a channel and domain.
586 * If name is NULL, all events are disabled.
587 * If channel_name is NULL, the default channel is used (channel0).
589 extern int lttng_disable_event(struct lttng_handle
*handle
,
590 const char *name
, const char *channel_name
);
596 extern int lttng_disable_channel(struct lttng_handle
*handle
,
600 * Calibrate LTTng overhead.
602 * The chan and handle params can not be NULL.
604 extern int lttng_calibrate(struct lttng_handle
*handle
,
605 struct lttng_calibrate
*calibrate
);
608 * Set the default channel attributes for a specific domain and an allocated
609 * lttng_channel_attr pointer.
611 * If one or both arguments are NULL, nothing happens.
613 extern void lttng_channel_set_default_attr(struct lttng_domain
*domain
,
614 struct lttng_channel_attr
*attr
);
617 * Set URL for a consumer for a session and domain.
619 * Both data and control URL must be defined. If both URLs are the same, only
620 * the control URL is used even for network streaming.
622 * Default port are 5342 and 5343 respectively for control and data which uses
625 extern int lttng_set_consumer_url(struct lttng_handle
*handle
,
626 const char *control_url
, const char *data_url
);
629 * Enable the consumer for a session and domain.
631 extern LTTNG_DEPRECATED("This call is now obsolete.")
632 int lttng_enable_consumer(struct lttng_handle
*handle
);
635 * Disable consumer for a session and domain.
637 extern LTTNG_DEPRECATED("This call is now obsolete.")
638 int lttng_disable_consumer(struct lttng_handle
*handle
);
641 * Check session daemon health for a specific component.
643 * Return 0 if health is OK or 1 if BAD. A returned value of -1 indicate that
644 * the control library was not able to connect to the session daemon health
647 * Any other positive value is an lttcomm error which can be translate with
650 * Please see lttng-health-check(3) man page for more information.
652 extern LTTNG_DEPRECATED("This call is now obsolete.")
653 int lttng_health_check(enum lttng_health_component c
);
656 * For a given session name, this call checks if the data is ready to be read
657 * or is still being extracted by the consumer(s) (pending) hence not ready to
658 * be used by any readers.
660 * Return 0 if there is _no_ data pending in the buffers thus having a
661 * guarantee that the data can be read safely. Else, return 1 if there is still
662 * traced data is pending. On error, a negative value is returned and readable
663 * by lttng_strerror().
665 extern int lttng_data_pending(const char *session_name
);