[lttng-ust.git] / include / lttng / ust-events.h

#ifndef _LTTNG_UST_EVENTS_H
#define _LTTNG_UST_EVENTS_H

/*
 * lttng/ust-events.h
 *
 * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * Holds LTTng per-session event registry.
 *
 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
 * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
 *
 * Permission is hereby granted to use or copy this program
 * for any purpose,  provided the above notices are retained on all copies.
 * Permission to modify the code and to distribute modified code is granted,
 * provided the above notices are retained, and a notice that the code was
 * modified is included with the above copyright notice.
 */

#include <urcu/list.h>
#include <urcu/hlist.h>
#include <uuid/uuid.h>
#include <stdint.h>
#include <lttng/ust-abi.h>
#include <lttng/ust-tracer.h>
#include <endian.h>
#include <float.h>

struct ltt_channel;
struct ltt_session;
struct lttng_ust_lib_ring_buffer_ctx;

/*
 * LTTng client type enumeration. Used by the consumer to map the
 * callbacks from its own address space.
 */
enum lttng_client_types {
	LTTNG_CLIENT_METADATA = 0,
	LTTNG_CLIENT_DISCARD = 1,
	LTTNG_CLIENT_OVERWRITE = 2,
	LTTNG_NR_CLIENT_TYPES,
};

/* Type description */

/* Update the astract_types name table in lttng-types.c along with this enum */
enum abstract_types {
	atype_integer,
	atype_enum,
	atype_array,
	atype_sequence,
	atype_string,
	atype_float,
	NR_ABSTRACT_TYPES,
};

/* Update the string_encodings name table in lttng-types.c along with this enum */
enum lttng_string_encodings {
	lttng_encode_none = 0,
	lttng_encode_UTF8 = 1,
	lttng_encode_ASCII = 2,
	NR_STRING_ENCODINGS,
};

struct lttng_enum_entry {
	unsigned long long start, end;	/* start and end are inclusive */
	const char *string;
};

#define __type_integer(_type, _byte_order, _base, _encoding)	\
	{							\
	    .atype = atype_integer,				\
	    .u.basic.integer =					\
		{						\
		  .size = sizeof(_type) * CHAR_BIT,		\
		  .alignment = lttng_alignof(_type) * CHAR_BIT,	\
		  .signedness = lttng_is_signed_type(_type),	\
		  .reverse_byte_order = _byte_order != __BYTE_ORDER,	\
		  .base = _base,				\
		  .encoding = lttng_encode_##_encoding,		\
		},						\
	}							\

struct lttng_integer_type {
	unsigned int size;		/* in bits */
	unsigned short alignment;	/* in bits */
	unsigned int signedness:1;
	unsigned int reverse_byte_order:1;
	unsigned int base;		/* 2, 8, 10, 16, for pretty print */
	enum lttng_string_encodings encoding;
};

/*
 * Only float and double are supported. long double is not supported at
 * the moment.
 */
#define _float_mant_dig(_type)						\
	(sizeof(_type) == sizeof(float) ? FLT_MANT_DIG			\
		: (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG	\
		: 0))

#define __type_float(_type)					\
	{							\
	    .atype = atype_float,				\
	    .u.basic._float =					\
		{						\
		  .exp_dig = sizeof(_type) * CHAR_BIT		\
				- _float_mant_dig(_type),	\
		  .mant_dig = _float_mant_dig(_type),		\
		  .alignment = lttng_alignof(_type) * CHAR_BIT,	\
		  .reverse_byte_order = __BYTE_ORDER != __FLOAT_WORD_ORDER, \
		},						\
	}							\

struct lttng_float_type {
	unsigned int exp_dig;		/* exponent digits, in bits */
	unsigned int mant_dig;		/* mantissa digits, in bits */
	unsigned short alignment;	/* in bits */
	unsigned int reverse_byte_order:1;
};

union _lttng_basic_type {
	struct lttng_integer_type integer;
	struct {
		const char *name;
	} enumeration;
	struct {
		enum lttng_string_encodings encoding;
	} string;
	struct lttng_float_type _float;
};

struct lttng_basic_type {
	enum abstract_types atype;
	union {
		union _lttng_basic_type basic;
	} u;
};

struct lttng_type {
	enum abstract_types atype;
	union {
		union _lttng_basic_type basic;
		struct {
			struct lttng_basic_type elem_type;
			unsigned int length;		/* num. elems. */
		} array;
		struct {
			struct lttng_basic_type length_type;
			struct lttng_basic_type elem_type;
		} sequence;
	} u;
};

struct lttng_enum {
	const char *name;
	struct lttng_type container_type;
	const struct lttng_enum_entry *entries;
	unsigned int len;
};

/* Event field description */

struct lttng_event_field {
	const char *name;
	struct lttng_type type;
};

struct lttng_ctx_field {
	struct lttng_event_field event_field;
	size_t (*get_size)(size_t offset);
	void (*record)(struct lttng_ctx_field *field,
		       struct lttng_ust_lib_ring_buffer_ctx *ctx,
		       struct ltt_channel *chan);
	union {
	} u;
	void (*destroy)(struct lttng_ctx_field *field);
};

struct lttng_ctx {
	struct lttng_ctx_field *fields;
	unsigned int nr_fields;
	unsigned int allocated_fields;
};

struct tracepoint_loglevel_entry  {
	const char *identifier;
	long value;
};

struct loglevel_entry;

/*
 * Entry describing a per-session active loglevel, along with the event
 * attribute and channel information configuring the events that need to
 * be enabled.
 */
struct session_loglevel {
	struct ltt_channel *chan;
	struct lttng_ctx *ctx;	/* TODO */
	struct lttng_ust_event event_param;
	struct cds_list_head events;	/* list of events enabled */
	struct cds_list_head list;	/* per-session list of loglevels */
	struct cds_list_head session_list;
	struct loglevel_entry *entry;
	unsigned int enabled:1;
};

/*
 * Entry describing an active loglevel (per name) for all sessions.
 */
struct loglevel_entry {
	struct cds_hlist_node hlist;
	struct cds_list_head session_list;
	char name[0];
};

/*
 * Entry describing a per-session active wildcard, along with the event
 * attribute and channel information configuring the events that need to
 * be enabled.
 */
struct session_wildcard {
	struct ltt_channel *chan;
	struct lttng_ctx *ctx;	/* TODO */
	struct lttng_ust_event event_param;
	struct cds_list_head events;	/* list of events enabled */
	struct cds_list_head list;	/* per-session list of wildcards */
	struct cds_list_head session_list;
	struct wildcard_entry *entry;
	unsigned int enabled:1;
};

/*
 * Entry describing an active wildcard (per name) for all sessions.
 */
struct wildcard_entry {
	struct cds_list_head list;
	struct cds_list_head session_list;
	char name[0];
};

struct lttng_event_desc {
	const char *name;
	void *probe_callback;
	const struct lttng_event_ctx *ctx;	/* context */
	const struct lttng_event_field *fields;	/* event payload */
	unsigned int nr_fields;
	const struct tracepoint_loglevel_entry **loglevel;
};

struct lttng_probe_desc {
	const char *provider;
	const struct lttng_event_desc **event_desc;
	unsigned int nr_events;
	const struct tracepoint_loglevel_entry **loglevels;
	unsigned int nr_loglevels;
	struct cds_list_head head;		/* chain registered probes */
};

struct tp_list_entry {
	struct lttng_ust_tracepoint_iter tp;
	struct cds_list_head head;
};

struct lttng_ust_tracepoint_list {
	struct tp_list_entry *iter;
	struct cds_list_head head;
};

struct ust_pending_probe;

/*
 * ltt_event structure is referred to by the tracing fast path. It must be
 * kept small.
 * Note about loglevel_list: this list is only used to enable/disable
 * events on a per-loglevel basis. The events created internally by the
 * loglevel are only freed when the session is destroyed.
 */
struct ltt_event {
	unsigned int id;
	struct ltt_channel *chan;
	int enabled;
	const struct lttng_event_desc *desc;
	void *filter;
	struct lttng_ctx *ctx;
	enum lttng_ust_instrumentation instrumentation;
	union {
	} u;
	struct cds_list_head list;		/* Event list */
	struct cds_list_head loglevel_list;	/* Event list for loglevel */
	struct cds_list_head wildcard_list;	/* Event list for wildcard */
	struct ust_pending_probe *pending_probe;
	unsigned int metadata_dumped:1;
};

struct channel;
struct lttng_ust_shm_handle;

struct ltt_channel_ops {
	struct ltt_channel *(*channel_create)(const char *name,
				void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval,
				int *shm_fd, int *wait_fd,
				uint64_t *memory_map_size,
				struct ltt_channel *chan_priv_init);
	void (*channel_destroy)(struct ltt_channel *ltt_chan);
	struct lttng_ust_lib_ring_buffer *(*buffer_read_open)(struct channel *chan,
				struct lttng_ust_shm_handle *handle,
				int *shm_fd, int *wait_fd,
				uint64_t *memory_map_size);
	void (*buffer_read_close)(struct lttng_ust_lib_ring_buffer *buf,
				struct lttng_ust_shm_handle *handle);
	int (*event_reserve)(struct lttng_ust_lib_ring_buffer_ctx *ctx,
			     uint32_t event_id);
	void (*event_commit)(struct lttng_ust_lib_ring_buffer_ctx *ctx);
	void (*event_write)(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
			    size_t len);
	/*
	 * packet_avail_size returns the available size in the current
	 * packet. Note that the size returned is only a hint, since it
	 * may change due to concurrent writes.
	 */
	size_t (*packet_avail_size)(struct channel *chan,
				    struct lttng_ust_shm_handle *handle);
	//wait_queue_head_t *(*get_reader_wait_queue)(struct channel *chan);
	//wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
	int (*is_finalized)(struct channel *chan);
	int (*is_disabled)(struct channel *chan);
	int (*flush_buffer)(struct channel *chan, struct lttng_ust_shm_handle *handle);
};

struct ltt_channel {
	/*
	 * The pointers located in this private data are NOT safe to be
	 * dereferenced by the consumer. The only operations the
	 * consumer process is designed to be allowed to do is to read
	 * and perform subbuffer flush.
	 */
	struct channel *chan;		/* Channel buffers */
	int enabled;
	struct lttng_ctx *ctx;
	/* Event ID management */
	struct ltt_session *session;
	int objd;			/* Object associated to channel */
	unsigned int free_event_id;	/* Next event ID to allocate */
	unsigned int used_event_id;	/* Max allocated event IDs */
	struct cds_list_head list;	/* Channel list */
	struct ltt_channel_ops *ops;
	int header_type;		/* 0: unset, 1: compact, 2: large */
	struct lttng_ust_shm_handle *handle;	/* shared-memory handle */
	unsigned int metadata_dumped:1;

	/* Channel ID, available for consumer too */
	unsigned int id;
	/* Copy of session UUID for consumer (availability through shm) */
	uuid_t uuid;			/* Trace session unique ID */
};

struct ltt_session {
	int active;			/* Is trace session active ? */
	int been_active;		/* Has trace session been active ? */
	int objd;			/* Object associated to session */
	struct ltt_channel *metadata;	/* Metadata channel */
	struct cds_list_head chan;	/* Channel list head */
	struct cds_list_head events;	/* Event list head */
	struct cds_list_head loglevels;	/* Loglevel list head */
	struct cds_list_head wildcards;	/* Wildcard list head */
	struct cds_list_head list;	/* Session list */
	unsigned int free_chan_id;	/* Next chan ID to allocate */
	uuid_t uuid;			/* Trace session unique ID */
	unsigned int metadata_dumped:1;
};

struct ltt_transport {
	char *name;
	struct cds_list_head node;
	struct ltt_channel_ops ops;
};

struct ltt_session *ltt_session_create(void);
int ltt_session_enable(struct ltt_session *session);
int ltt_session_disable(struct ltt_session *session);
void ltt_session_destroy(struct ltt_session *session);

struct ltt_channel *ltt_channel_create(struct ltt_session *session,
				       const char *transport_name,
				       void *buf_addr,
				       size_t subbuf_size, size_t num_subbuf,
				       unsigned int switch_timer_interval,
				       unsigned int read_timer_interval,
				       int *shm_fd, int *wait_fd,
				       uint64_t *memory_map_size,
				       struct ltt_channel *chan_priv_init);
struct ltt_channel *ltt_global_channel_create(struct ltt_session *session,
				       int overwrite, void *buf_addr,
				       size_t subbuf_size, size_t num_subbuf,
				       unsigned int switch_timer_interval,
				       unsigned int read_timer_interval,
				       int *shm_fd, int *wait_fd,
				       uint64_t *memory_map_size);

int ltt_event_create(struct ltt_channel *chan,
		struct lttng_ust_event *event_param,
		void *filter,
		struct ltt_event **event);

int ltt_channel_enable(struct ltt_channel *channel);
int ltt_channel_disable(struct ltt_channel *channel);
int ltt_event_enable(struct ltt_event *event);
int ltt_event_disable(struct ltt_event *event);

void ltt_transport_register(struct ltt_transport *transport);
void ltt_transport_unregister(struct ltt_transport *transport);

void synchronize_trace(void);

int ltt_probe_register(struct lttng_probe_desc *desc);
void ltt_probe_unregister(struct lttng_probe_desc *desc);
int pending_probe_fix_events(const struct lttng_event_desc *desc);
const struct lttng_event_desc *ltt_event_get(const char *name);
void ltt_event_put(const struct lttng_event_desc *desc);
int ltt_probes_init(void);
void ltt_probes_exit(void);
int lttng_find_context(struct lttng_ctx *ctx, const char *name);
struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p);
void lttng_remove_context_field(struct lttng_ctx **ctx_p,
				struct lttng_ctx_field *field);
void lttng_destroy_context(struct lttng_ctx *ctx);
int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
void lttng_context_vtid_reset(void);
void lttng_context_vpid_reset(void);

const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;

struct ltt_transport *ltt_transport_find(const char *name);

int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
struct lttng_ust_tracepoint_iter *
	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);

struct loglevel_entry *get_loglevel(const char *name);
struct loglevel_entry *get_loglevel_value(int64_t value);
struct session_loglevel *add_loglevel(const char *name,
	struct ltt_channel *chan,
	struct lttng_ust_event *event_param);
void _remove_loglevel(struct session_loglevel *loglevel);
int ltt_loglevel_enable(struct session_loglevel *loglevel);
int ltt_loglevel_disable(struct session_loglevel *loglevel);
int ltt_loglevel_create(struct ltt_channel *chan,
	struct lttng_ust_event *event_param,
	struct session_loglevel **sl);

struct wildcard_entry *match_wildcard(const char *name);
struct session_wildcard *add_wildcard(const char *name,
	struct ltt_channel *chan,
	struct lttng_ust_event *event_param);
void _remove_wildcard(struct session_wildcard *wildcard);
int ltt_wildcard_enable(struct session_wildcard *wildcard);
int ltt_wildcard_disable(struct session_wildcard *wildcard);
int ltt_wildcard_create(struct ltt_channel *chan,
	struct lttng_ust_event *event_param,
	struct session_wildcard **sl);

#endif /* _LTTNG_UST_EVENTS_H */
Commit	Line	Data
	1	#ifndef _LTTNG_UST_EVENTS_H
	2	#define _LTTNG_UST_EVENTS_H
	3
	4	/*
	5	* lttng/ust-events.h
	6	*
	7	* Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* Holds LTTng per-session event registry.
	10	*
	11	* THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
	12	* OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
	13	*
	14	* Permission is hereby granted to use or copy this program
	15	* for any purpose, provided the above notices are retained on all copies.
	16	* Permission to modify the code and to distribute modified code is granted,
	17	* provided the above notices are retained, and a notice that the code was
	18	* modified is included with the above copyright notice.
	19	*/
	20
	21	#include <urcu/list.h>
	22	#include <urcu/hlist.h>
	23	#include <uuid/uuid.h>
	24	#include <stdint.h>
	25	#include <lttng/ust-abi.h>
	26	#include <lttng/ust-tracer.h>
	27	#include <endian.h>
	28	#include <float.h>
	29
	30	struct ltt_channel;
	31	struct ltt_session;
	32	struct lttng_ust_lib_ring_buffer_ctx;
	33
	34	/*
	35	* LTTng client type enumeration. Used by the consumer to map the
	36	* callbacks from its own address space.
	37	*/
	38	enum lttng_client_types {
	39	LTTNG_CLIENT_METADATA = 0,
	40	LTTNG_CLIENT_DISCARD = 1,
	41	LTTNG_CLIENT_OVERWRITE = 2,
	42	LTTNG_NR_CLIENT_TYPES,
	43	};
	44
	45	/* Type description */
	46
	47	/* Update the astract_types name table in lttng-types.c along with this enum */
	48	enum abstract_types {
	49	atype_integer,
	50	atype_enum,
	51	atype_array,
	52	atype_sequence,
	53	atype_string,
	54	atype_float,
	55	NR_ABSTRACT_TYPES,
	56	};
	57
	58	/* Update the string_encodings name table in lttng-types.c along with this enum */
	59	enum lttng_string_encodings {
	60	lttng_encode_none = 0,
	61	lttng_encode_UTF8 = 1,
	62	lttng_encode_ASCII = 2,
	63	NR_STRING_ENCODINGS,
	64	};
	65
	66	struct lttng_enum_entry {
	67	unsigned long long start, end; /* start and end are inclusive */
	68	const char *string;
	69	};
	70
	71	#define __type_integer(_type, _byte_order, _base, _encoding) \
	72	{ \
	73	.atype = atype_integer, \
	74	.u.basic.integer = \
	75	{ \
	76	.size = sizeof(_type) * CHAR_BIT, \
	77	.alignment = lttng_alignof(_type) * CHAR_BIT, \
	78	.signedness = lttng_is_signed_type(_type), \
	79	.reverse_byte_order = _byte_order != __BYTE_ORDER, \
	80	.base = _base, \
	81	.encoding = lttng_encode_##_encoding, \
	82	}, \
	83	} \
	84
	85	struct lttng_integer_type {
	86	unsigned int size; /* in bits */
	87	unsigned short alignment; /* in bits */
	88	unsigned int signedness:1;
	89	unsigned int reverse_byte_order:1;
	90	unsigned int base; /* 2, 8, 10, 16, for pretty print */
	91	enum lttng_string_encodings encoding;
	92	};
	93
	94	/*
	95	* Only float and double are supported. long double is not supported at
	96	* the moment.
	97	*/
	98	#define _float_mant_dig(_type) \
	99	(sizeof(_type) == sizeof(float) ? FLT_MANT_DIG \
	100	: (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG \
	101	: 0))
	102
	103	#define __type_float(_type) \
	104	{ \
	105	.atype = atype_float, \
	106	.u.basic._float = \
	107	{ \
	108	.exp_dig = sizeof(_type) * CHAR_BIT \
	109	- _float_mant_dig(_type), \
	110	.mant_dig = _float_mant_dig(_type), \
	111	.alignment = lttng_alignof(_type) * CHAR_BIT, \
	112	.reverse_byte_order = __BYTE_ORDER != __FLOAT_WORD_ORDER, \
	113	}, \
	114	} \
	115
	116	struct lttng_float_type {
	117	unsigned int exp_dig; /* exponent digits, in bits */
	118	unsigned int mant_dig; /* mantissa digits, in bits */
	119	unsigned short alignment; /* in bits */
	120	unsigned int reverse_byte_order:1;
	121	};
	122
	123	union _lttng_basic_type {
	124	struct lttng_integer_type integer;
	125	struct {
	126	const char *name;
	127	} enumeration;
	128	struct {
	129	enum lttng_string_encodings encoding;
	130	} string;
	131	struct lttng_float_type _float;
	132	};
	133
	134	struct lttng_basic_type {
	135	enum abstract_types atype;
	136	union {
	137	union _lttng_basic_type basic;
	138	} u;
	139	};
	140
	141	struct lttng_type {
	142	enum abstract_types atype;
	143	union {
	144	union _lttng_basic_type basic;
	145	struct {
	146	struct lttng_basic_type elem_type;
	147	unsigned int length; /* num. elems. */
	148	} array;
	149	struct {
	150	struct lttng_basic_type length_type;
	151	struct lttng_basic_type elem_type;
	152	} sequence;
	153	} u;
	154	};
	155
	156	struct lttng_enum {
	157	const char *name;
	158	struct lttng_type container_type;
	159	const struct lttng_enum_entry *entries;
	160	unsigned int len;
	161	};
	162
	163	/* Event field description */
	164
	165	struct lttng_event_field {
	166	const char *name;
	167	struct lttng_type type;
	168	};
	169
	170	struct lttng_ctx_field {
	171	struct lttng_event_field event_field;
	172	size_t (*get_size)(size_t offset);
	173	void (record)(struct lttng_ctx_field field,
	174	struct lttng_ust_lib_ring_buffer_ctx *ctx,
	175	struct ltt_channel *chan);
	176	union {
	177	} u;
	178	void (destroy)(struct lttng_ctx_field field);
	179	};
	180
	181	struct lttng_ctx {
	182	struct lttng_ctx_field *fields;
	183	unsigned int nr_fields;
	184	unsigned int allocated_fields;
	185	};
	186
	187	struct tracepoint_loglevel_entry {
	188	const char *identifier;
	189	long value;
	190	};
	191
	192	struct loglevel_entry;
	193
	194	/*
	195	* Entry describing a per-session active loglevel, along with the event
	196	* attribute and channel information configuring the events that need to
	197	* be enabled.
	198	*/
	199	struct session_loglevel {
	200	struct ltt_channel *chan;
	201	struct lttng_ctx ctx; / TODO */
	202	struct lttng_ust_event event_param;
	203	struct cds_list_head events; /* list of events enabled */
	204	struct cds_list_head list; /* per-session list of loglevels */
	205	struct cds_list_head session_list;
	206	struct loglevel_entry *entry;
	207	unsigned int enabled:1;
	208	};
	209
	210	/*
	211	* Entry describing an active loglevel (per name) for all sessions.
	212	*/
	213	struct loglevel_entry {
	214	struct cds_hlist_node hlist;
	215	struct cds_list_head session_list;
	216	char name[0];
	217	};
	218
	219	/*
	220	* Entry describing a per-session active wildcard, along with the event
	221	* attribute and channel information configuring the events that need to
	222	* be enabled.
	223	*/
	224	struct session_wildcard {
	225	struct ltt_channel *chan;
	226	struct lttng_ctx ctx; / TODO */
	227	struct lttng_ust_event event_param;
	228	struct cds_list_head events; /* list of events enabled */
	229	struct cds_list_head list; /* per-session list of wildcards */
	230	struct cds_list_head session_list;
	231	struct wildcard_entry *entry;
	232	unsigned int enabled:1;
	233	};
	234
	235	/*
	236	* Entry describing an active wildcard (per name) for all sessions.
	237	*/
	238	struct wildcard_entry {
	239	struct cds_list_head list;
	240	struct cds_list_head session_list;
	241	char name[0];
	242	};
	243
	244	struct lttng_event_desc {
	245	const char *name;
	246	void *probe_callback;
	247	const struct lttng_event_ctx ctx; / context */
	248	const struct lttng_event_field fields; / event payload */
	249	unsigned int nr_fields;
	250	const struct tracepoint_loglevel_entry **loglevel;
	251	};
	252
	253	struct lttng_probe_desc {
	254	const char *provider;
	255	const struct lttng_event_desc **event_desc;
	256	unsigned int nr_events;
	257	const struct tracepoint_loglevel_entry **loglevels;
	258	unsigned int nr_loglevels;
	259	struct cds_list_head head; /* chain registered probes */
	260	};
	261
	262	struct tp_list_entry {
	263	struct lttng_ust_tracepoint_iter tp;
	264	struct cds_list_head head;
	265	};
	266
	267	struct lttng_ust_tracepoint_list {
	268	struct tp_list_entry *iter;
	269	struct cds_list_head head;
	270	};
	271
	272	struct ust_pending_probe;
	273
	274	/*
	275	* ltt_event structure is referred to by the tracing fast path. It must be
	276	* kept small.
	277	* Note about loglevel_list: this list is only used to enable/disable
	278	* events on a per-loglevel basis. The events created internally by the
	279	* loglevel are only freed when the session is destroyed.
	280	*/
	281	struct ltt_event {
	282	unsigned int id;
	283	struct ltt_channel *chan;
	284	int enabled;
	285	const struct lttng_event_desc *desc;
	286	void *filter;
	287	struct lttng_ctx *ctx;
	288	enum lttng_ust_instrumentation instrumentation;
	289	union {
	290	} u;
	291	struct cds_list_head list; /* Event list */
	292	struct cds_list_head loglevel_list; /* Event list for loglevel */
	293	struct cds_list_head wildcard_list; /* Event list for wildcard */
	294	struct ust_pending_probe *pending_probe;
	295	unsigned int metadata_dumped:1;
	296	};
	297
	298	struct channel;
	299	struct lttng_ust_shm_handle;
	300
	301	struct ltt_channel_ops {
	302	struct ltt_channel (channel_create)(const char *name,
	303	void *buf_addr,
	304	size_t subbuf_size, size_t num_subbuf,
	305	unsigned int switch_timer_interval,
	306	unsigned int read_timer_interval,
	307	int shm_fd, int wait_fd,
	308	uint64_t *memory_map_size,
	309	struct ltt_channel *chan_priv_init);
	310	void (channel_destroy)(struct ltt_channel ltt_chan);
	311	struct lttng_ust_lib_ring_buffer (buffer_read_open)(struct channel *chan,
	312	struct lttng_ust_shm_handle *handle,
	313	int shm_fd, int wait_fd,
	314	uint64_t *memory_map_size);
	315	void (buffer_read_close)(struct lttng_ust_lib_ring_buffer buf,
	316	struct lttng_ust_shm_handle *handle);
	317	int (event_reserve)(struct lttng_ust_lib_ring_buffer_ctx ctx,
	318	uint32_t event_id);
	319	void (event_commit)(struct lttng_ust_lib_ring_buffer_ctx ctx);
	320	void (event_write)(struct lttng_ust_lib_ring_buffer_ctx ctx, const void *src,
	321	size_t len);
	322	/*
	323	* packet_avail_size returns the available size in the current
	324	* packet. Note that the size returned is only a hint, since it
	325	* may change due to concurrent writes.
	326	*/
	327	size_t (packet_avail_size)(struct channel chan,
	328	struct lttng_ust_shm_handle *handle);
	329	//wait_queue_head_t (get_reader_wait_queue)(struct channel *chan);
	330	//wait_queue_head_t (get_hp_wait_queue)(struct channel *chan);
	331	int (is_finalized)(struct channel chan);
	332	int (is_disabled)(struct channel chan);
	333	int (flush_buffer)(struct channel chan, struct lttng_ust_shm_handle *handle);
	334	};
	335
	336	struct ltt_channel {
	337	/*
	338	* The pointers located in this private data are NOT safe to be
	339	* dereferenced by the consumer. The only operations the
	340	* consumer process is designed to be allowed to do is to read
	341	* and perform subbuffer flush.
	342	*/
	343	struct channel chan; / Channel buffers */
	344	int enabled;
	345	struct lttng_ctx *ctx;
	346	/* Event ID management */
	347	struct ltt_session *session;
	348	int objd; /* Object associated to channel */
	349	unsigned int free_event_id; /* Next event ID to allocate */
	350	unsigned int used_event_id; /* Max allocated event IDs */
	351	struct cds_list_head list; /* Channel list */
	352	struct ltt_channel_ops *ops;
	353	int header_type; /* 0: unset, 1: compact, 2: large */
	354	struct lttng_ust_shm_handle handle; / shared-memory handle */
	355	unsigned int metadata_dumped:1;
	356
	357	/* Channel ID, available for consumer too */
	358	unsigned int id;
	359	/* Copy of session UUID for consumer (availability through shm) */
	360	uuid_t uuid; /* Trace session unique ID */
	361	};
	362
	363	struct ltt_session {
	364	int active; /* Is trace session active ? */
	365	int been_active; /* Has trace session been active ? */
	366	int objd; /* Object associated to session */
	367	struct ltt_channel metadata; / Metadata channel */
	368	struct cds_list_head chan; /* Channel list head */
	369	struct cds_list_head events; /* Event list head */
	370	struct cds_list_head loglevels; /* Loglevel list head */
	371	struct cds_list_head wildcards; /* Wildcard list head */
	372	struct cds_list_head list; /* Session list */
	373	unsigned int free_chan_id; /* Next chan ID to allocate */
	374	uuid_t uuid; /* Trace session unique ID */
	375	unsigned int metadata_dumped:1;
	376	};
	377
	378	struct ltt_transport {
	379	char *name;
	380	struct cds_list_head node;
	381	struct ltt_channel_ops ops;
	382	};
	383
	384	struct ltt_session *ltt_session_create(void);
	385	int ltt_session_enable(struct ltt_session *session);
	386	int ltt_session_disable(struct ltt_session *session);
	387	void ltt_session_destroy(struct ltt_session *session);
	388
	389	struct ltt_channel ltt_channel_create(struct ltt_session session,
	390	const char *transport_name,
	391	void *buf_addr,
	392	size_t subbuf_size, size_t num_subbuf,
	393	unsigned int switch_timer_interval,
	394	unsigned int read_timer_interval,
	395	int shm_fd, int wait_fd,
	396	uint64_t *memory_map_size,
	397	struct ltt_channel *chan_priv_init);
	398	struct ltt_channel ltt_global_channel_create(struct ltt_session session,
	399	int overwrite, void *buf_addr,
	400	size_t subbuf_size, size_t num_subbuf,
	401	unsigned int switch_timer_interval,
	402	unsigned int read_timer_interval,
	403	int shm_fd, int wait_fd,
	404	uint64_t *memory_map_size);
	405
	406	int ltt_event_create(struct ltt_channel *chan,
	407	struct lttng_ust_event *event_param,
	408	void *filter,
	409	struct ltt_event **event);
	410
	411	int ltt_channel_enable(struct ltt_channel *channel);
	412	int ltt_channel_disable(struct ltt_channel *channel);
	413	int ltt_event_enable(struct ltt_event *event);
	414	int ltt_event_disable(struct ltt_event *event);
	415
	416	void ltt_transport_register(struct ltt_transport *transport);
	417	void ltt_transport_unregister(struct ltt_transport *transport);
	418
	419	void synchronize_trace(void);
	420
	421	int ltt_probe_register(struct lttng_probe_desc *desc);
	422	void ltt_probe_unregister(struct lttng_probe_desc *desc);
	423	int pending_probe_fix_events(const struct lttng_event_desc *desc);
	424	const struct lttng_event_desc ltt_event_get(const char name);
	425	void ltt_event_put(const struct lttng_event_desc *desc);
	426	int ltt_probes_init(void);
	427	void ltt_probes_exit(void);
	428	int lttng_find_context(struct lttng_ctx ctx, const char name);
	429	struct lttng_ctx_field lttng_append_context(struct lttng_ctx *ctx_p);
	430	void lttng_remove_context_field(struct lttng_ctx **ctx_p,
	431	struct lttng_ctx_field *field);
	432	void lttng_destroy_context(struct lttng_ctx *ctx);
	433	int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
	434	int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
	435	int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
	436	int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
	437	void lttng_context_vtid_reset(void);
	438	void lttng_context_vpid_reset(void);
	439
	440	const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
	441	const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
	442	const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
	443
	444	struct ltt_transport ltt_transport_find(const char name);
	445
	446	int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
	447	void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
	448	struct lttng_ust_tracepoint_iter *
	449	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
	450
	451	struct loglevel_entry get_loglevel(const char name);
	452	struct loglevel_entry *get_loglevel_value(int64_t value);
	453	struct session_loglevel add_loglevel(const char name,
	454	struct ltt_channel *chan,
	455	struct lttng_ust_event *event_param);
	456	void _remove_loglevel(struct session_loglevel *loglevel);
	457	int ltt_loglevel_enable(struct session_loglevel *loglevel);
	458	int ltt_loglevel_disable(struct session_loglevel *loglevel);
	459	int ltt_loglevel_create(struct ltt_channel *chan,
	460	struct lttng_ust_event *event_param,
	461	struct session_loglevel **sl);
	462
	463	struct wildcard_entry match_wildcard(const char name);
	464	struct session_wildcard add_wildcard(const char name,
	465	struct ltt_channel *chan,
	466	struct lttng_ust_event *event_param);
	467	void _remove_wildcard(struct session_wildcard *wildcard);
	468	int ltt_wildcard_enable(struct session_wildcard *wildcard);
	469	int ltt_wildcard_disable(struct session_wildcard *wildcard);
	470	int ltt_wildcard_create(struct ltt_channel *chan,
	471	struct lttng_ust_event *event_param,
	472	struct session_wildcard **sl);
	473
	474	#endif /* _LTTNG_UST_EVENTS_H */