[lttng-tools.git] / include / lttng / channel.h

/*
 * Copyright (C) 2014 - David Goulet <dgoulet@efficios.com>
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License, version 2.1 only,
 * as published by the Free Software Foundation.
 *
 * This library 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef LTTNG_CHANNEL_H
#define LTTNG_CHANNEL_H

#include <lttng/domain.h>
#include <lttng/event.h>
#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Tracer channel attributes. For both kernel and user-space.
 *
 * The structures should be initialized to zero before use.
 */
#define LTTNG_CHANNEL_ATTR_PADDING1        LTTNG_SYMBOL_NAME_LEN + 12
struct lttng_channel_attr {
	int overwrite;                      /* 1: overwrite, 0: discard */
	uint64_t subbuf_size;               /* bytes, power of 2 */
	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 */
	/* LTTng 2.1 padding limit */
	uint64_t tracefile_size;            /* bytes */
	uint64_t tracefile_count;           /* number of tracefiles */
	/* LTTng 2.3 padding limit */
	unsigned int live_timer_interval;   /* usec */
	/* LTTng 2.7 padding limit */
	uint32_t align_to_64;
	union {
		uint64_t padding;
		void *ptr;
	} extended;

	char padding[LTTNG_CHANNEL_ATTR_PADDING1];
};

/*
 * Channel information structure. For both kernel and user-space.
 *
 * The structures should be initialized to zero before use.
 */
#define LTTNG_CHANNEL_PADDING1             16
struct lttng_channel {
	char name[LTTNG_SYMBOL_NAME_LEN];
	uint32_t enabled;
	struct lttng_channel_attr attr;

	char padding[LTTNG_CHANNEL_PADDING1];
};

/*
 * List the channel(s) of a session.
 *
 * The handle CAN NOT be NULL.
 *
 * Return the size (number of entries) of the "lttng_channel" array. Caller
 * must free channels. On error, a negative LTTng error code is returned.
 */
extern int lttng_list_channels(struct lttng_handle *handle,
		struct lttng_channel **channels);

/*
 * Create or enable a channel.
 *
 * The chan and handle params can not be NULL.
 *
 * Return 0 on success else a negative LTTng error code.
 */
extern int lttng_enable_channel(struct lttng_handle *handle,
		struct lttng_channel *chan);

/*
 * Disable channel.
 *
 * Name and handle CAN NOT be NULL.
 *
 * Return 0 on success else a negative LTTng error code.
 */
extern int lttng_disable_channel(struct lttng_handle *handle,
		const char *name);

/*
 * Set the default channel attributes for a specific domain and an allocated
 * lttng_channel_attr pointer.
 *
 * If one or both arguments are NULL, nothing happens.
 */
extern void lttng_channel_set_default_attr(struct lttng_domain *domain,
		struct lttng_channel_attr *attr);

/*
 * Get the discarded event count of a specific LTTng channel.
 *
 * Returns 0 on success, or a negative LTTng error code on error.
 */
extern int lttng_channel_get_discarded_event_count(struct lttng_channel *chan,
		uint64_t *discarded_events);

/*
 * Get the lost packet count of a specific LTTng channel.
 *
 * Returns 0 on success, or a negative LTTng error code on error.
 */
extern int lttng_channel_get_lost_packet_count(struct lttng_channel *chan,
		uint64_t *lost_packets);

#ifdef __cplusplus
}
#endif

#endif /* LTTNG_CHANNEL_H */
Commit	Line	Data
1239a312 DG	1	/*
	2	* Copyright (C) 2014 - David Goulet <dgoulet@efficios.com>
	3	*
	4	* This library is free software; you can redistribute it and/or modify it
	5	* under the terms of the GNU Lesser General Public License, version 2.1 only,
	6	* as published by the Free Software Foundation.
	7	*
	8	* This library is distributed in the hope that it will be useful, but WITHOUT
	9	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	10	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
	11	* for more details.
	12	*
	13	* You should have received a copy of the GNU Lesser General Public License
	14	* along with this library; if not, write to the Free Software Foundation,
	15	* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	16	*/
	17
	18	#ifndef LTTNG_CHANNEL_H
	19	#define LTTNG_CHANNEL_H
	20
	21	#include <lttng/domain.h>
	22	#include <lttng/event.h>
5ba3702f	23	#include <stdint.h>
1239a312 DG	24
	25	#ifdef __cplusplus
	26	extern "C" {
	27	#endif
	28
	29	/*
	30	* Tracer channel attributes. For both kernel and user-space.
	31	*
	32	* The structures should be initialized to zero before use.
	33	*/
	34	#define LTTNG_CHANNEL_ATTR_PADDING1 LTTNG_SYMBOL_NAME_LEN + 12
	35	struct lttng_channel_attr {
	36	int overwrite; /* 1: overwrite, 0: discard */
7daee932	37	uint64_t subbuf_size; /* bytes, power of 2 */
1239a312 DG	38	uint64_t num_subbuf; /* power of 2 */
	39	unsigned int switch_timer_interval; /* usec */
	40	unsigned int read_timer_interval; /* usec */
	41	enum lttng_event_output output; /* splice, mmap */
	42	/* LTTng 2.1 padding limit */
	43	uint64_t tracefile_size; /* bytes */
	44	uint64_t tracefile_count; /* number of tracefiles */
	45	/* LTTng 2.3 padding limit */
	46	unsigned int live_timer_interval; /* usec */
67487150 JG	47	/* LTTng 2.7 padding limit */
	48	uint32_t align_to_64;
	49	union {
	50	uint64_t padding;
	51	void *ptr;
	52	} extended;
1239a312 DG	53
	54	char padding[LTTNG_CHANNEL_ATTR_PADDING1];
	55	};
	56
	57	/*
	58	* Channel information structure. For both kernel and user-space.
	59	*
	60	* The structures should be initialized to zero before use.
	61	*/
	62	#define LTTNG_CHANNEL_PADDING1 16
	63	struct lttng_channel {
	64	char name[LTTNG_SYMBOL_NAME_LEN];
	65	uint32_t enabled;
	66	struct lttng_channel_attr attr;
	67
	68	char padding[LTTNG_CHANNEL_PADDING1];
	69	};
	70
	71	/*
	72	* List the channel(s) of a session.
	73	*
	74	* The handle CAN NOT be NULL.
	75	*
	76	* Return the size (number of entries) of the "lttng_channel" array. Caller
	77	* must free channels. On error, a negative LTTng error code is returned.
	78	*/
	79	extern int lttng_list_channels(struct lttng_handle *handle,
	80	struct lttng_channel **channels);
	81
	82	/*
	83	* Create or enable a channel.
	84	*
	85	* The chan and handle params can not be NULL.
	86	*
	87	* Return 0 on success else a negative LTTng error code.
	88	*/
	89	extern int lttng_enable_channel(struct lttng_handle *handle,
	90	struct lttng_channel *chan);
	91
	92	/*
	93	* Disable channel.
	94	*
	95	* Name and handle CAN NOT be NULL.
	96	*
	97	* Return 0 on success else a negative LTTng error code.
	98	*/
	99	extern int lttng_disable_channel(struct lttng_handle *handle,
	100	const char *name);
	101
	102	/*
	103	* Set the default channel attributes for a specific domain and an allocated
	104	* lttng_channel_attr pointer.
	105	*
	106	* If one or both arguments are NULL, nothing happens.
	107	*/
	108	extern void lttng_channel_set_default_attr(struct lttng_domain *domain,
	109	struct lttng_channel_attr *attr);
	110
5ba3702f JG	111	/*
	112	* Get the discarded event count of a specific LTTng channel.
	113	*
	114	* Returns 0 on success, or a negative LTTng error code on error.
	115	*/
	116	extern int lttng_channel_get_discarded_event_count(struct lttng_channel *chan,
	117	uint64_t *discarded_events);
	118
	119	/*
	120	* Get the lost packet count of a specific LTTng channel.
	121	*
	122	* Returns 0 on success, or a negative LTTng error code on error.
	123	*/
	124	extern int lttng_channel_get_lost_packet_count(struct lttng_channel *chan,
	125	uint64_t *lost_packets);
	126
1239a312 DG	127	#ifdef __cplusplus
	128	}
	129	#endif
	130
	131	#endif /* LTTNG_CHANNEL_H */