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

#ifndef _LTTNG_UST_EVENTS_H
#define _LTTNG_UST_EVENTS_H

/*
 * lttng/ust-events.h
 *
 * Copyright 2010-2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * Holds LTTng per-session event registry.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 */

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

#define LTTNG_UST_UUID_LEN		16

struct ltt_channel;
struct ltt_session;
struct lttng_ust_lib_ring_buffer_ctx;

/*
 * Data structures used by tracepoint event declarations, and by the
 * tracer. Those structures have padding for future extension.
 */

/*
 * 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,
};

#define LTTNG_UST_ENUM_ENTRY_PADDING	16
struct lttng_enum_entry {
	unsigned long long start, end;	/* start and end are inclusive */
	const char *string;
	char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
};

#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,		\
		},						\
	}							\

#define LTTNG_UST_INTEGER_TYPE_PADDING	24
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;
	char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
};

/*
 * 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, \
		},						\
	}							\

#define LTTNG_UST_FLOAT_TYPE_PADDING	24
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;
	char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
};

#define LTTNG_UST_BASIC_TYPE_PADDING	128
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;
	char padding[LTTNG_UST_BASIC_TYPE_PADDING];
};

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

#define LTTNG_UST_TYPE_PADDING	128
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;
		char padding[LTTNG_UST_TYPE_PADDING];
	} u;
};

#define LTTNG_UST_ENUM_TYPE_PADDING	24
struct lttng_enum {
	const char *name;
	struct lttng_type container_type;
	const struct lttng_enum_entry *entries;
	unsigned int len;
	char padding[LTTNG_UST_ENUM_TYPE_PADDING];
};

/* Event field description */

#define LTTNG_UST_EVENT_FIELD_PADDING	32
struct lttng_event_field {
	const char *name;
	struct lttng_type type;
	char padding[LTTNG_UST_EVENT_FIELD_PADDING];
};

#define LTTNG_UST_CTX_FIELD_PADDING	40
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 {
		char padding[LTTNG_UST_CTX_FIELD_PADDING];
	} u;
	void (*destroy)(struct lttng_ctx_field *field);
};

#define LTTNG_UST_CTX_PADDING	24
struct lttng_ctx {
	struct lttng_ctx_field *fields;
	unsigned int nr_fields;
	unsigned int allocated_fields;
	char padding[LTTNG_UST_CTX_PADDING];
};

#define LTTNG_UST_EVENT_DESC_PADDING	40
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 int **loglevel;
	const char *signature;	/* Argument types/names received */
	char padding[LTTNG_UST_EVENT_DESC_PADDING];
};

#define LTTNG_UST_PROBE_DESC_PADDING	40
struct lttng_probe_desc {
	const char *provider;
	const struct lttng_event_desc **event_desc;
	unsigned int nr_events;
	struct cds_list_head head;		/* chain registered probes */
	char padding[LTTNG_UST_PROBE_DESC_PADDING];
};

/* Data structures used by the tracer. */

/*
 * 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; /* node of session wildcard list */
	struct wildcard_entry *entry;
	unsigned int enabled:1;
};

/*
 * Entry describing an active wildcard (per name) for all sessions.
 */
struct wildcard_entry {
	/* node of global wildcards list */
	struct cds_list_head list;
	/* head of session list to which this wildcard apply */
	struct cds_list_head session_list;
	enum lttng_ust_loglevel_type loglevel_type;
	int loglevel;
	char name[0];
};

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.
 */
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 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) */
	unsigned char uuid[LTTNG_UST_UUID_LEN]; /* 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 wildcards;	/* Wildcard list head */
	struct cds_list_head list;	/* Session list */
	unsigned int free_chan_id;	/* Next chan ID to allocate */
	unsigned char uuid[LTTNG_UST_UUID_LEN]; /* 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);

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);
int ltt_loglevel_match(const struct lttng_event_desc *desc,
		enum lttng_ust_loglevel_type req_type,
		int req_loglevel);
void ltt_probes_create_wildcard_events(struct wildcard_entry *entry,
				struct session_wildcard *wildcard);

#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 2010-2012 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* Holds LTTng per-session event registry.
	10	*
	11	* Permission is hereby granted, free of charge, to any person obtaining a copy
	12	* of this software and associated documentation files (the "Software"), to deal
	13	* in the Software without restriction, including without limitation the rights
	14	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	15	* copies of the Software, and to permit persons to whom the Software is
	16	* furnished to do so, subject to the following conditions:
	17	*
	18	* The above copyright notice and this permission notice shall be included in
	19	* all copies or substantial portions of the Software.
	20	*/
	21
	22	#include <urcu/list.h>
	23	#include <urcu/hlist.h>
	24	#include <stdint.h>
	25	#include <lttng/ust-abi.h>
	26	#include <lttng/ust-tracer.h>
	27	#include <lttng/ust-endian.h>
	28	#include <float.h>
	29
	30	#define LTTNG_UST_UUID_LEN 16
	31
	32	struct ltt_channel;
	33	struct ltt_session;
	34	struct lttng_ust_lib_ring_buffer_ctx;
	35
	36	/*
	37	* Data structures used by tracepoint event declarations, and by the
	38	* tracer. Those structures have padding for future extension.
	39	*/
	40
	41	/*
	42	* LTTng client type enumeration. Used by the consumer to map the
	43	* callbacks from its own address space.
	44	*/
	45	enum lttng_client_types {
	46	LTTNG_CLIENT_METADATA = 0,
	47	LTTNG_CLIENT_DISCARD = 1,
	48	LTTNG_CLIENT_OVERWRITE = 2,
	49	LTTNG_NR_CLIENT_TYPES,
	50	};
	51
	52	/* Type description */
	53
	54	/* Update the astract_types name table in lttng-types.c along with this enum */
	55	enum abstract_types {
	56	atype_integer,
	57	atype_enum,
	58	atype_array,
	59	atype_sequence,
	60	atype_string,
	61	atype_float,
	62	NR_ABSTRACT_TYPES,
	63	};
	64
	65	/* Update the string_encodings name table in lttng-types.c along with this enum */
	66	enum lttng_string_encodings {
	67	lttng_encode_none = 0,
	68	lttng_encode_UTF8 = 1,
	69	lttng_encode_ASCII = 2,
	70	NR_STRING_ENCODINGS,
	71	};
	72
	73	#define LTTNG_UST_ENUM_ENTRY_PADDING 16
	74	struct lttng_enum_entry {
	75	unsigned long long start, end; /* start and end are inclusive */
	76	const char *string;
	77	char padding[LTTNG_UST_ENUM_ENTRY_PADDING];
	78	};
	79
	80	#define __type_integer(_type, _byte_order, _base, _encoding) \
	81	{ \
	82	.atype = atype_integer, \
	83	.u.basic.integer = \
	84	{ \
	85	.size = sizeof(_type) * CHAR_BIT, \
	86	.alignment = lttng_alignof(_type) * CHAR_BIT, \
	87	.signedness = lttng_is_signed_type(_type), \
	88	.reverse_byte_order = _byte_order != BYTE_ORDER, \
	89	.base = _base, \
	90	.encoding = lttng_encode_##_encoding, \
	91	}, \
	92	} \
	93
	94	#define LTTNG_UST_INTEGER_TYPE_PADDING 24
	95	struct lttng_integer_type {
	96	unsigned int size; /* in bits */
	97	unsigned short alignment; /* in bits */
	98	unsigned int signedness:1;
	99	unsigned int reverse_byte_order:1;
	100	unsigned int base; /* 2, 8, 10, 16, for pretty print */
	101	enum lttng_string_encodings encoding;
	102	char padding[LTTNG_UST_INTEGER_TYPE_PADDING];
	103	};
	104
	105	/*
	106	* Only float and double are supported. long double is not supported at
	107	* the moment.
	108	*/
	109	#define _float_mant_dig(_type) \
	110	(sizeof(_type) == sizeof(float) ? FLT_MANT_DIG \
	111	: (sizeof(_type) == sizeof(double) ? DBL_MANT_DIG \
	112	: 0))
	113
	114	#define __type_float(_type) \
	115	{ \
	116	.atype = atype_float, \
	117	.u.basic._float = \
	118	{ \
	119	.exp_dig = sizeof(_type) * CHAR_BIT \
	120	- _float_mant_dig(_type), \
	121	.mant_dig = _float_mant_dig(_type), \
	122	.alignment = lttng_alignof(_type) * CHAR_BIT, \
	123	.reverse_byte_order = BYTE_ORDER != FLOAT_WORD_ORDER, \
	124	}, \
	125	} \
	126
	127	#define LTTNG_UST_FLOAT_TYPE_PADDING 24
	128	struct lttng_float_type {
	129	unsigned int exp_dig; /* exponent digits, in bits */
	130	unsigned int mant_dig; /* mantissa digits, in bits */
	131	unsigned short alignment; /* in bits */
	132	unsigned int reverse_byte_order:1;
	133	char padding[LTTNG_UST_FLOAT_TYPE_PADDING];
	134	};
	135
	136	#define LTTNG_UST_BASIC_TYPE_PADDING 128
	137	union _lttng_basic_type {
	138	struct lttng_integer_type integer;
	139	struct {
	140	const char *name;
	141	} enumeration;
	142	struct {
	143	enum lttng_string_encodings encoding;
	144	} string;
	145	struct lttng_float_type _float;
	146	char padding[LTTNG_UST_BASIC_TYPE_PADDING];
	147	};
	148
	149	struct lttng_basic_type {
	150	enum abstract_types atype;
	151	union {
	152	union _lttng_basic_type basic;
	153	} u;
	154	};
	155
	156	#define LTTNG_UST_TYPE_PADDING 128
	157	struct lttng_type {
	158	enum abstract_types atype;
	159	union {
	160	union _lttng_basic_type basic;
	161	struct {
	162	struct lttng_basic_type elem_type;
	163	unsigned int length; /* num. elems. */
	164	} array;
	165	struct {
	166	struct lttng_basic_type length_type;
	167	struct lttng_basic_type elem_type;
	168	} sequence;
	169	char padding[LTTNG_UST_TYPE_PADDING];
	170	} u;
	171	};
	172
	173	#define LTTNG_UST_ENUM_TYPE_PADDING 24
	174	struct lttng_enum {
	175	const char *name;
	176	struct lttng_type container_type;
	177	const struct lttng_enum_entry *entries;
	178	unsigned int len;
	179	char padding[LTTNG_UST_ENUM_TYPE_PADDING];
	180	};
	181
	182	/* Event field description */
	183
	184	#define LTTNG_UST_EVENT_FIELD_PADDING 32
	185	struct lttng_event_field {
	186	const char *name;
	187	struct lttng_type type;
	188	char padding[LTTNG_UST_EVENT_FIELD_PADDING];
	189	};
	190
	191	#define LTTNG_UST_CTX_FIELD_PADDING 40
	192	struct lttng_ctx_field {
	193	struct lttng_event_field event_field;
	194	size_t (*get_size)(size_t offset);
	195	void (record)(struct lttng_ctx_field field,
	196	struct lttng_ust_lib_ring_buffer_ctx *ctx,
	197	struct ltt_channel *chan);
	198	union {
	199	char padding[LTTNG_UST_CTX_FIELD_PADDING];
	200	} u;
	201	void (destroy)(struct lttng_ctx_field field);
	202	};
	203
	204	#define LTTNG_UST_CTX_PADDING 24
	205	struct lttng_ctx {
	206	struct lttng_ctx_field *fields;
	207	unsigned int nr_fields;
	208	unsigned int allocated_fields;
	209	char padding[LTTNG_UST_CTX_PADDING];
	210	};
	211
	212	#define LTTNG_UST_EVENT_DESC_PADDING 40
	213	struct lttng_event_desc {
	214	const char *name;
	215	void *probe_callback;
	216	const struct lttng_event_ctx ctx; / context */
	217	const struct lttng_event_field fields; / event payload */
	218	unsigned int nr_fields;
	219	const int **loglevel;
	220	const char signature; / Argument types/names received */
	221	char padding[LTTNG_UST_EVENT_DESC_PADDING];
	222	};
	223
	224	#define LTTNG_UST_PROBE_DESC_PADDING 40
	225	struct lttng_probe_desc {
	226	const char *provider;
	227	const struct lttng_event_desc **event_desc;
	228	unsigned int nr_events;
	229	struct cds_list_head head; /* chain registered probes */
	230	char padding[LTTNG_UST_PROBE_DESC_PADDING];
	231	};
	232
	233	/* Data structures used by the tracer. */
	234
	235	/*
	236	* Entry describing a per-session active wildcard, along with the event
	237	* attribute and channel information configuring the events that need to
	238	* be enabled.
	239	*/
	240	struct session_wildcard {
	241	struct ltt_channel *chan;
	242	struct lttng_ctx ctx; / TODO */
	243	struct lttng_ust_event event_param;
	244	struct cds_list_head events; /* list of events enabled */
	245	struct cds_list_head list; /* per-session list of wildcards */
	246	struct cds_list_head session_list; /* node of session wildcard list */
	247	struct wildcard_entry *entry;
	248	unsigned int enabled:1;
	249	};
	250
	251	/*
	252	* Entry describing an active wildcard (per name) for all sessions.
	253	*/
	254	struct wildcard_entry {
	255	/* node of global wildcards list */
	256	struct cds_list_head list;
	257	/* head of session list to which this wildcard apply */
	258	struct cds_list_head session_list;
	259	enum lttng_ust_loglevel_type loglevel_type;
	260	int loglevel;
	261	char name[0];
	262	};
	263
	264	struct tp_list_entry {
	265	struct lttng_ust_tracepoint_iter tp;
	266	struct cds_list_head head;
	267	};
	268
	269	struct lttng_ust_tracepoint_list {
	270	struct tp_list_entry *iter;
	271	struct cds_list_head head;
	272	};
	273
	274	struct ust_pending_probe;
	275
	276	/*
	277	* ltt_event structure is referred to by the tracing fast path. It must be
	278	* kept small.
	279	*/
	280	struct ltt_event {
	281	unsigned int id;
	282	struct ltt_channel *chan;
	283	int enabled;
	284	const struct lttng_event_desc *desc;
	285	void *filter;
	286	struct lttng_ctx *ctx;
	287	enum lttng_ust_instrumentation instrumentation;
	288	union {
	289	} u;
	290	struct cds_list_head list; /* Event list */
	291	struct cds_list_head wildcard_list; /* Event list for wildcard */
	292	struct ust_pending_probe *pending_probe;
	293	unsigned int metadata_dumped:1;
	294	};
	295
	296	struct channel;
	297	struct lttng_ust_shm_handle;
	298
	299	struct ltt_channel_ops {
	300	struct ltt_channel (channel_create)(const char *name,
	301	void *buf_addr,
	302	size_t subbuf_size, size_t num_subbuf,
	303	unsigned int switch_timer_interval,
	304	unsigned int read_timer_interval,
	305	int shm_fd, int wait_fd,
	306	uint64_t **memory_map_size,
	307	struct ltt_channel *chan_priv_init);
	308	void (channel_destroy)(struct ltt_channel ltt_chan);
	309	struct lttng_ust_lib_ring_buffer (buffer_read_open)(struct channel *chan,
	310	struct lttng_ust_shm_handle *handle,
	311	int shm_fd, int wait_fd,
	312	uint64_t **memory_map_size);
	313	void (buffer_read_close)(struct lttng_ust_lib_ring_buffer buf,
	314	struct lttng_ust_shm_handle *handle);
	315	int (event_reserve)(struct lttng_ust_lib_ring_buffer_ctx ctx,
	316	uint32_t event_id);
	317	void (event_commit)(struct lttng_ust_lib_ring_buffer_ctx ctx);
	318	void (event_write)(struct lttng_ust_lib_ring_buffer_ctx ctx, const void *src,
	319	size_t len);
	320	/*
	321	* packet_avail_size returns the available size in the current
	322	* packet. Note that the size returned is only a hint, since it
	323	* may change due to concurrent writes.
	324	*/
	325	size_t (packet_avail_size)(struct channel chan,
	326	struct lttng_ust_shm_handle *handle);
	327	//wait_queue_head_t (get_reader_wait_queue)(struct channel *chan);
	328	//wait_queue_head_t (get_hp_wait_queue)(struct channel *chan);
	329	int (is_finalized)(struct channel chan);
	330	int (is_disabled)(struct channel chan);
	331	int (flush_buffer)(struct channel chan, struct lttng_ust_shm_handle *handle);
	332	};
	333
	334	struct ltt_channel {
	335	/*
	336	* The pointers located in this private data are NOT safe to be
	337	* dereferenced by the consumer. The only operations the
	338	* consumer process is designed to be allowed to do is to read
	339	* and perform subbuffer flush.
	340	*/
	341	struct channel chan; / Channel buffers */
	342	int enabled;
	343	struct lttng_ctx *ctx;
	344	/* Event ID management */
	345	struct ltt_session *session;
	346	int objd; /* Object associated to channel */
	347	unsigned int free_event_id; /* Next event ID to allocate */
	348	unsigned int used_event_id; /* Max allocated event IDs */
	349	struct cds_list_head list; /* Channel list */
	350	struct ltt_channel_ops *ops;
	351	int header_type; /* 0: unset, 1: compact, 2: large */
	352	struct lttng_ust_shm_handle handle; / shared-memory handle */
	353	unsigned int metadata_dumped:1;
	354
	355	/* Channel ID, available for consumer too */
	356	unsigned int id;
	357	/* Copy of session UUID for consumer (availability through shm) */
	358	unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
	359	};
	360
	361	struct ltt_session {
	362	int active; /* Is trace session active ? */
	363	int been_active; /* Has trace session been active ? */
	364	int objd; /* Object associated to session */
	365	struct ltt_channel metadata; / Metadata channel */
	366	struct cds_list_head chan; /* Channel list head */
	367	struct cds_list_head events; /* Event list head */
	368	struct cds_list_head wildcards; /* Wildcard list head */
	369	struct cds_list_head list; /* Session list */
	370	unsigned int free_chan_id; /* Next chan ID to allocate */
	371	unsigned char uuid[LTTNG_UST_UUID_LEN]; /* Trace session unique ID */
	372	unsigned int metadata_dumped:1;
	373	};
	374
	375	struct ltt_transport {
	376	char *name;
	377	struct cds_list_head node;
	378	struct ltt_channel_ops ops;
	379	};
	380
	381	struct ltt_session *ltt_session_create(void);
	382	int ltt_session_enable(struct ltt_session *session);
	383	int ltt_session_disable(struct ltt_session *session);
	384	void ltt_session_destroy(struct ltt_session *session);
	385
	386	struct ltt_channel ltt_channel_create(struct ltt_session session,
	387	const char *transport_name,
	388	void *buf_addr,
	389	size_t subbuf_size, size_t num_subbuf,
	390	unsigned int switch_timer_interval,
	391	unsigned int read_timer_interval,
	392	int shm_fd, int wait_fd,
	393	uint64_t **memory_map_size,
	394	struct ltt_channel *chan_priv_init);
	395	struct ltt_channel ltt_global_channel_create(struct ltt_session session,
	396	int overwrite, void *buf_addr,
	397	size_t subbuf_size, size_t num_subbuf,
	398	unsigned int switch_timer_interval,
	399	unsigned int read_timer_interval,
	400	int shm_fd, int wait_fd,
	401	uint64_t **memory_map_size);
	402
	403	int ltt_event_create(struct ltt_channel *chan,
	404	struct lttng_ust_event *event_param,
	405	void *filter,
	406	struct ltt_event **event);
	407
	408	int ltt_channel_enable(struct ltt_channel *channel);
	409	int ltt_channel_disable(struct ltt_channel *channel);
	410	int ltt_event_enable(struct ltt_event *event);
	411	int ltt_event_disable(struct ltt_event *event);
	412
	413	void ltt_transport_register(struct ltt_transport *transport);
	414	void ltt_transport_unregister(struct ltt_transport *transport);
	415
	416	void synchronize_trace(void);
	417
	418	int ltt_probe_register(struct lttng_probe_desc *desc);
	419	void ltt_probe_unregister(struct lttng_probe_desc *desc);
	420	int pending_probe_fix_events(const struct lttng_event_desc *desc);
	421	const struct lttng_event_desc ltt_event_get(const char name);
	422	void ltt_event_put(const struct lttng_event_desc *desc);
	423	int ltt_probes_init(void);
	424	void ltt_probes_exit(void);
	425	int lttng_find_context(struct lttng_ctx ctx, const char name);
	426	struct lttng_ctx_field lttng_append_context(struct lttng_ctx *ctx_p);
	427	void lttng_remove_context_field(struct lttng_ctx **ctx_p,
	428	struct lttng_ctx_field *field);
	429	void lttng_destroy_context(struct lttng_ctx *ctx);
	430	int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
	431	int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
	432	int lttng_add_pthread_id_to_ctx(struct lttng_ctx **ctx);
	433	int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
	434	void lttng_context_vtid_reset(void);
	435	void lttng_context_vpid_reset(void);
	436
	437	const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_metadata;
	438	const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_discard;
	439	const struct lttng_ust_lib_ring_buffer_client_cb *lttng_client_callbacks_overwrite;
	440
	441	struct ltt_transport ltt_transport_find(const char name);
	442
	443	int ltt_probes_get_event_list(struct lttng_ust_tracepoint_list *list);
	444	void ltt_probes_prune_event_list(struct lttng_ust_tracepoint_list *list);
	445	struct lttng_ust_tracepoint_iter *
	446	lttng_ust_tracepoint_list_get_iter_next(struct lttng_ust_tracepoint_list *list);
	447
	448	int ltt_wildcard_enable(struct session_wildcard *wildcard);
	449	int ltt_wildcard_disable(struct session_wildcard *wildcard);
	450	int ltt_wildcard_create(struct ltt_channel *chan,
	451	struct lttng_ust_event *event_param,
	452	struct session_wildcard **sl);
	453	int ltt_loglevel_match(const struct lttng_event_desc *desc,
	454	enum lttng_ust_loglevel_type req_type,
	455	int req_loglevel);
	456	void ltt_probes_create_wildcard_events(struct wildcard_entry *entry,
	457	struct session_wildcard *wildcard);
	458
	459	#endif /* _LTTNG_UST_EVENTS_H */