X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=include%2Flttng%2Flttng.h;h=825b6682bbee9f39cbaaf2c0093cc1ba3984cdca;hb=HEAD;hp=ac7c435044d47a481bb1c29c081b039e75115127;hpb=f05b5f07dd61554a2fcdc5a09d4d80cadf478a51;p=lttng-tools.git diff --git a/include/lttng/lttng.h b/include/lttng/lttng.h index ac7c43504..6ae331bda 100644 --- a/include/lttng/lttng.h +++ b/include/lttng/lttng.h @@ -3,210 +3,499 @@ * * Linux Trace Toolkit Control Library Header File * - * Copyright (C) 2011 - David Goulet + * Copyright (C) 2011 EfficiOS Inc. + * + * SPDX-License-Identifier: LGPL-2.1-only * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -#ifndef _LTTNG_H -#define _LTTNG_H +#ifndef LTTNG_H +#define LTTNG_H + +#include + +/* Error codes that can be returned by API calls */ +#include + +/* Include every LTTng ABI/API available. */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef __cplusplus +extern "C" { +#endif + +enum lttng_calibrate_type { + LTTNG_CALIBRATE_FUNCTION = 0, +}; -#include -#include -#include +/* Machine interface output type */ +enum lttng_mi_output_type { + LTTNG_MI_XML = 1 /* XML output */ +}; -/* Default unix group name for tracing. */ -#define LTTNG_DEFAULT_TRACING_GROUP "tracing" +#define LTTNG_CALIBRATE_PADDING1 16 +struct lttng_calibrate { + enum lttng_calibrate_type type; -/* Environment variable to set session daemon binary path. */ -#define LTTNG_SESSIOND_PATH_ENV "LTTNG_SESSIOND_PATH" + char padding[LTTNG_CALIBRATE_PADDING1]; +}; -/* Default trace output directory name */ -#define LTTNG_DEFAULT_TRACE_DIR_NAME "lttng-traces" +/*! +@brief + Returns whether or not liblttng-ctl is able to connect to a + listening session daemon. -/* - * Event symbol length. Copied from LTTng kernel ABI. - */ -#define LTTNG_SYMBOL_NAME_LEN 128 +@ingroup api_gen -/* - * Every lttng_event_* structure both apply to kernel event and user-space - * event. - * - * Every lttng_kernel_* is copied from the LTTng kernel ABI. - */ +How this function tries to +\ref api-gen-sessiond-conn "connect to a session daemon" depends on the +current Unix tracing group (initially \c tracing) of the library. Set +the tracing group with lttng_set_tracing_group(). -enum lttng_event_type { - LTTNG_EVENT_TRACEPOINT, - LTTNG_EVENT_KPROBE, - LTTNG_EVENT_FUNCTION, -}; +@returns + @parblock + One of: -/* - * LTTng consumer mode - */ -enum lttng_event_output { - /* Using splice(2) */ - LTTNG_EVENT_SPLICE = 0, - /* Using mmap(2) */ - LTTNG_EVENT_MMAP = 1, -}; +
+
1
+
+ liblttng-ctl is able to connect to a session daemon. -/* Kernel context possible type */ -enum lttng_kernel_context_type { - LTTNG_KERNEL_CONTEXT_PID = 0, - LTTNG_KERNEL_CONTEXT_PERF_COUNTER = 1, - LTTNG_KERNEL_CONTEXT_COMM = 2, - LTTNG_KERNEL_CONTEXT_PRIO = 3, - LTTNG_KERNEL_CONTEXT_NICE = 4, - LTTNG_KERNEL_CONTEXT_VPID = 5, - LTTNG_KERNEL_CONTEXT_TID = 6, - LTTNG_KERNEL_CONTEXT_VTID = 7, - LTTNG_KERNEL_CONTEXT_PPID = 8, - LTTNG_KERNEL_CONTEXT_VPPID = 9, -}; +
0 +
+ liblttng-ctl isn't able to connect to a session daemon. -/* Perf counter attributes */ -struct lttng_kernel_perf_counter_ctx { - uint32_t type; - uint64_t config; - char name[LTTNG_SYMBOL_NAME_LEN]; -}; +
Negative value +
+ Error: a negative #lttng_error_code enumerator. +
+ @endparblock -/* Event/Channel context */ -struct lttng_kernel_context { - enum lttng_kernel_context_type ctx; - union { - struct lttng_kernel_perf_counter_ctx perf_counter; - } u; -}; +@sa lttng_set_tracing_group() -- + Sets the current Unix tracing group of liblttng-ctl. +*/ +LTTNG_EXPORT extern int lttng_session_daemon_alive(void); -/* - * Kernel Kprobe. Either addr is used or symbol_name and offset. - */ -struct lttng_kernel_kprobe_attr { - uint64_t addr; +/*! +@brief + Sets the current Unix tracing group of liblttng-ctl to \lt_p{group}. - uint64_t offset; - char symbol_name[LTTNG_SYMBOL_NAME_LEN]; -}; +@ingroup api_gen -/* - * Function tracer - */ -struct lttng_event_function_attr { - char symbol_name[LTTNG_SYMBOL_NAME_LEN]; -}; +How the liblttng-ctl functions +\ref api-gen-sessiond-conn "connect to a session daemon" depends on +the current Unix tracing group (initially \c tracing) of the library. -/* - * Generic lttng event - */ -struct lttng_event { - char name[LTTNG_SYMBOL_NAME_LEN]; - enum lttng_event_type type; - /* Per event type configuration */ - union { - struct lttng_kernel_kprobe_attr kprobe; - struct lttng_event_function_attr ftrace; - } attr; -}; +@param[in] group + New Unix tracing group of liblttng-ctl. -/* - * Tracer channel attributes. For both kernel and user-space. - */ -struct lttng_channel_attr { - int overwrite; /* 1: overwrite, 0: discard */ - uint64_t subbuf_size; /* bytes */ - uint64_t num_subbuf; /* power of 2 */ - unsigned int switch_timer_interval; /* usec */ - unsigned int read_timer_interval; /* usec */ - enum lttng_event_output output; /* splice, mmap */ -}; +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. -/* - * Channel information structure. For both kernel and user-space. - */ -struct lttng_channel { - char name[NAME_MAX]; - struct lttng_channel_attr attr; -}; +@lt_pre_not_null{group} +@pre + \lt_p{group} names an existing Unix group. +*/ +LTTNG_EXPORT extern int lttng_set_tracing_group(const char *group); /* - * Basic session information. + * This call registers an "outside consumer" for a session and an lttng domain. + * No consumer will be spawned and all fds/commands will go through the socket + * path given (socket_path). * - * This is an 'output data' meaning that it only comes *from* the session - * daemon *to* the lttng client. It's basically a 'human' representation of - * tracing entities (here a session). + * NOTE that this is not recommended unless you absolutely know what you are + * doing. + * + * Return 0 on success else a negative LTTng error code. */ -struct lttng_session { - char name[NAME_MAX]; - /* The path where traces are written */ - char path[PATH_MAX]; -}; +LTTNG_EXPORT extern int lttng_register_consumer(struct lttng_handle *handle, + const char *socket_path); + +/*! +@brief + Makes the recording session named \lt_p{session_name} active, + starting all the tracers for its + \ref api-channel-channel "channels". + +@ingroup api_session + +@note + An #LTTNG_ACTION_TYPE_START_SESSION trigger action can also activate + (start) a recording session. + +@param[in] session_name + Name of the recording session to activate/start. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} +@lt_pre_sess_inactive{session_name} + +@sa lttng_stop_tracing() -- + Stops a recording session. +@sa \lt_man{lttng-start,1} +*/ +LTTNG_EXPORT extern int lttng_start_tracing(const char *session_name); + +/*! +@brief + Makes the recording session named \lt_p{session_name} inactive, + stopping all the tracers for its + \ref api-channel-channel "channels", blocking until the operation + completes. + +@ingroup api_session + +This function blocks until the trace data of the +recording session named \lt_p{session_name} is valid. Use +lttng_stop_tracing_no_wait() to avoid a blocking call. + +If LTTng \ref api_session_rotation "archived the current trace chunk" +of the recording session named \lt_p{session_name} at least +once during its lifetime, then this function renames the current trace +chunk subdirectory. Although it's safe to +read the content of this renamed subdirectory while the recording +session remains inactive, it's \em not a trace chunk archive: you need to +\link lttng_destroy_session_ext() destroy\endlink the recording session +or a rotation needs to occur to archive it. + +@note + An #LTTNG_ACTION_TYPE_STOP_SESSION trigger action can also + deactivate (stop) a recording session. + +@param[in] session_name + Name of the recording session to deactivate/stop. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} +@lt_pre_sess_active{session_name} + +@sa lttng_stop_tracing_no_wait() -- + Deactivates a recording session without waiting for the operation + to complete. +@sa lttng_start_tracing() -- + Starts a recording session. +@sa \lt_man{lttng-stop,1} +*/ +LTTNG_EXPORT extern int lttng_stop_tracing(const char *session_name); + +/*! +@brief + Makes the recording session named \lt_p{session_name} inactive, + stopping all the tracers for its + \ref api-channel-channel "channels" without waiting for the + operation to complete. + +@ingroup api_session + +Unlike lttng_stop_tracing(), this function does \em not block until +the operation is complete: it returns immediately. This +means the traces(s) of the recording session might not be valid when +this function returns, and there's no way to know when it/they become +valid. + +@note + An #LTTNG_ACTION_TYPE_STOP_SESSION trigger action can also + deactivate (stop) a recording session. + +@param[in] session_name + Name of the recording session to deactivate/stop. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} +@lt_pre_sess_active{session_name} +@pre + No deactivation operation is in progress for the recording session + named \lt_p{session_name}. + +@sa lttng_stop_tracing() -- + Deactivates a recording session, blocking until the operation + completes. +@sa lttng_start_tracing() -- + Starts a recording session. +@sa \lt_man{lttng-stop,1} +*/ +LTTNG_EXPORT extern int lttng_stop_tracing_no_wait(const char *session_name); /* - * Session daemon control + * Deprecated: As of LTTng 2.9, this function always returns + * -LTTNG_ERR_UND. */ -extern int lttng_connect_sessiond(void); - -extern int lttng_create_session(char *name, char *path); - -extern int lttng_destroy_session(char *name); - -extern int lttng_disconnect_sessiond(void); +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wshadow" +LTTNG_EXPORT extern int lttng_calibrate(struct lttng_handle *handle, + struct lttng_calibrate *calibrate); +#pragma GCC diagnostic pop /* - * Return a "lttng_session" array. Caller must free(3) the returned data. - */ -extern int lttng_list_sessions(struct lttng_session **sessions); - -extern int lttng_session_daemon_alive(void); - -/* Set tracing group for the current execution */ -extern int lttng_set_tracing_group(const char *name); - -extern void lttng_set_session_name(char *name); - -extern const char *lttng_get_readable_code(int code); - -extern int lttng_start_tracing(char *session_name); - -extern int lttng_stop_tracing(char *session_name); - -/* - * LTTng Kernel tracer control + * Set URL for a consumer for a session and domain. + * + * Both data and control URL must be defined. If both URLs are the same, only + * the control URL is used even for network streaming. + * + * Default port are 5342 and 5343 respectively for control and data which uses + * the TCP protocol. + * + * URL format: proto://[HOST|IP][:PORT1[:PORT2]][/TRACE_PATH] + * + * Possible protocols are: + * > file://... + * Local filesystem full path. + * + * > net[6]://... + * This will use the default network transport layer which is TCP for both + * control (PORT1) and data port (PORT2). + * + * > tcp[6]://... + * TCP only streaming. For this one, both data and control URL must be given. + * + * Return 0 on success else a negative LTTng error code. */ -extern int lttng_kernel_add_context(struct lttng_kernel_context *ctx, - char *event_name, char *channel_name); - -extern int lttng_kernel_create_channel(struct lttng_channel *chan); - -extern int lttng_kernel_enable_event(struct lttng_event *ev, char *channel_name); - -extern int lttng_kernel_enable_channel(char *name); - -extern int lttng_kernel_disable_event(char *name, char *channel_name); - -extern int lttng_kernel_disable_channel(char *name); - -extern int lttng_kernel_list_events(char **event_list); +LTTNG_EXPORT extern int +lttng_set_consumer_url(struct lttng_handle *handle, const char *control_url, const char *data_url); + +/*! +@brief + Returns whether or not you may read the traces of the recording + session named \lt_p{session_name}. + +@ingroup api_session + +It's not safe to read the traces of a recording session while +LTTng is still consuming data from the tracers for its +\ref api-channel-channel "channels". + +This function makes it possible to know when LTTng is done consuming +trace data from tracers for the channels of the recording session +named \lt_p{session_name}. + +@param[in] session_name + Name of the recording session of which get whether or not + you may read its traces. + +@returns + @parblock + One of: + +
+
0 +
+ You may read the traces of the recording session named + \lt_p{session_name}. + + This remains true as long as the recording session remains + \link lttng_session::enabled inactive\endlink (stopped). + +
1
+
+ You may \em not read the traces of the recording session named + \lt_p{session_name}. + +
Negative value +
+ Error: a negative #lttng_error_code enumerator. +
+ @endparblock + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} +@lt_pre_sess_inactive{session_name} +*/ +LTTNG_EXPORT extern int lttng_data_pending(const char *session_name); /* - * LTTng User-space tracer control + * Gets the status of the kernel tracer. + * + * Sets the value of the argument, which must not be null. */ - -//extern int lttng_ust_list_traceable_apps(pid_t **pids); - -#endif /* _LTTNG_H */ +LTTNG_EXPORT extern enum lttng_error_code +lttng_get_kernel_tracer_status(enum lttng_kernel_tracer_status *status); + +/*! +@brief + Regenerates the metadata streams of the recording session named + \lt_p{session_name}. + +@ingroup api_session + +@deprecated + Use lttng_regenerate_metadata(). + +@param[in] session_name + Name of the recording session of which to regenerate the metadata + streams. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} +*/ +/// @cond DEPRECATED +LTTNG_DEPRECATED() +/// @endcond +LTTNG_EXPORT extern int lttng_metadata_regenerate(const char *session_name); + +/*! +@brief + Regenerates the metadata streams of the recording session named + \lt_p{session_name}. + +@ingroup api_session + +Use this function to resample the offset between the monotonic clock and +the wall time of the system, and then regenerate (overwrite) all the +metadata stream files (local or remote) of the recording session +named \lt_p{session_name}. + +More specifically, you may want to resample the wall time following a +major NTP +correction. As such, LTTng can trace a system booting with an incorrect +wall time before its wall time is NTP-corrected. Regenerating the +metadata of a recording session ensures that trace readers +can accurately determine the event record timestamps relative to the +Unix epoch. + +Note that if you plan to \ref api_session_rotation "rotate" the +recording session named \lt_p{session_name}, this function only +regenerates the metadata stream files of the \em current and \em next +trace chunks. + +See the preconditions of this function which show important limitations. + +@param[in] session_name + Name of the recording session of which to regenerate the metadata + streams. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} +@pre + The recording session named \lt_p{session_name} was \em not created + in \ref api-session-live-mode "live mode". +@pre + All the \ref api-channel-channel "channels" of the recording session + named \lt_p{session_name} use a + \ref api-channel-per-user-buf "per-user buffering scheme". + +@sa lttng_regenerate_statedump() -- + Regenerates the state dump event records of a recording session. +@sa \lt_man{lttng-regenerate,1} +*/ +LTTNG_EXPORT extern int lttng_regenerate_metadata(const char *session_name); + +/*! +@brief + Regenerates the state dump event records of the recording session + named \lt_p{session_name}. + +@ingroup api_session + +Use this function to collect up-to-date state dump information and +append corresponding event records to the +\ref api-channel-channel "sub-buffers" of the recording session named +\lt_p{session_name}. + +This is particularly useful if you created the recording session in +\ref api-session-snapshot-mode "snapshot mode" +or if LTTng \ref api_session_rotation "rotates" trace files for one of +its \ref api-channel-channel "channels": in both cases, the state dump +information may be lost. + +@param[in] session_name + Name of the recording session of which to regenerate the + state dump event records. + +@returns + 0 on success, or a \em negative #lttng_error_code enumerator + otherwise. + +@lt_pre_conn +@lt_pre_not_null{session_name} +@lt_pre_sess_exists{session_name} + +@sa lttng_regenerate_metadata() -- + Regenerates the metadata streams of a recording session. +@sa \lt_man{lttng-regenerate,1} +*/ +LTTNG_EXPORT extern int lttng_regenerate_statedump(const char *session_name); + +#ifdef __cplusplus +} +#endif + +#endif /* LTTNG_H */