[deliverable/lttng-modules.git] / ltt-events.h

#ifndef _LTT_EVENTS_H
#define _LTT_EVENTS_H

/*
 * ltt-events.h
 *
 * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * Holds LTTng per-session event registry.
 */

#include <linux/list.h>
#include <linux/uuid.h>
#include <linux/kprobes.h>
#include "ltt-debugfs-abi.h"

struct ltt_channel;
struct ltt_session;
struct lib_ring_buffer_ctx;
struct perf_event;
struct perf_event_attr;

/* 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,
	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)		\
	{							\
	    .atype = atype_integer,				\
	    .u.basic.integer =					\
		{						\
		  .size = sizeof(_type) * CHAR_BIT,		\
		  .alignment = ltt_alignof(_type) * CHAR_BIT,	\
		  .signedness = is_signed_type(_type),		\
		  .reverse_byte_order = _byte_order != __BYTE_ORDER,	\
		  .base = _base,				\
		  .encoding = lttng_encode_none,		\
		},						\
	}							\

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;
};

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

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 {
	const char *name;
	struct lttng_type type;
	void *callback;
	union {
		struct {
			struct perf_event **e;	/* per-cpu array */
			struct list_head head;
			struct perf_event_attr *attr;
		} perf_counter;
	} u;
};

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

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;
};

struct lttng_probe_desc {
	const struct lttng_event_desc *event_desc;
	unsigned int nr_events;
	struct list_head head;			/* chain registered probes */
};

/*
 * 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;
	const struct lttng_event_desc *desc;
	void *filter;
	enum lttng_kernel_instrumentation instrumentation;
	union {
		struct {
			struct kprobe kp;
			char *symbol_name;
		} kprobe;
		struct {
			char *symbol_name;
		} ftrace;
	} u;
	struct list_head list;		/* Event list */
	int metadata_dumped:1;
};

struct ltt_channel_ops {
	struct channel *(*channel_create)(const char *name,
				struct ltt_channel *ltt_chan,
				void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval);
	void (*channel_destroy)(struct channel *chan);
	struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan);
	void (*buffer_read_close)(struct lib_ring_buffer *buf);
	int (*event_reserve)(struct lib_ring_buffer_ctx *ctx,
			     uint16_t event_id);
	void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
	void (*event_write)(struct 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);
	wait_queue_head_t *(*get_reader_wait_queue)(struct ltt_channel *chan);
};

struct ltt_channel {
	unsigned int id;
	struct channel *chan;		/* Channel buffers */
	/* Event ID management */
	struct ltt_session *session;
	struct file *file;		/* File associated to channel */
	unsigned int free_event_id;	/* Next event ID to allocate */
	struct list_head list;		/* Channel list */
	wait_queue_head_t notify_wait;	/* Channel addition notif. waitqueue */
	struct ltt_channel_ops *ops;
	int header_type;		/* 0: unset, 1: compact, 2: large */
	int metadata_dumped:1;
};

struct ltt_session {
	int active;			/* Is trace session active ? */
	struct file *file;		/* File associated to session */
	struct ltt_channel *metadata;	/* Metadata channel */
	struct list_head chan;		/* Channel list head */
	struct list_head events;	/* Event list head */
	struct list_head list;		/* Session list */
	unsigned int free_chan_id;	/* Next chan ID to allocate */
	uuid_le uuid;			/* Trace session unique ID */
	int metadata_dumped:1;
};

struct ltt_transport {
	char *name;
	struct module *owner;
	struct list_head node;
	struct ltt_channel_ops ops;
};

struct ltt_session *ltt_session_create(void);
int ltt_session_start(struct ltt_session *session);
int ltt_session_stop(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);
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);

struct ltt_event *ltt_event_create(struct ltt_channel *chan,
				   struct lttng_kernel_event *event_param,
				   void *filter);

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

int ltt_debugfs_abi_init(void);
void ltt_debugfs_abi_exit(void);

int ltt_probe_register(struct lttng_probe_desc *desc);
void ltt_probe_unregister(struct lttng_probe_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);

#ifdef CONFIG_KPROBES
int lttng_kprobes_register(const char *name,
		const char *symbol_name,
		uint64_t offset,
		uint64_t addr,
		struct ltt_event *event);
void lttng_kprobes_unregister(struct ltt_event *event);
#else
static inline
int lttng_kprobes_register(const char *name,
		const char *symbol_name,
		uint64_t offset,
		uint64_t addr,
		struct ltt_event *event)
{
	return -ENOSYS;
}

static inline
void lttng_kprobes_unregister(struct ltt_event *event)
{
}
#endif

#ifdef CONFIG_DYNAMIC_FTRACE
int lttng_ftrace_register(const char *name,
			  const char *symbol_name,
			  struct ltt_event *event);
void lttng_ftrace_unregister(struct ltt_event *event);
#else
static inline
int lttng_ftrace_register(const char *name,
			  const char *symbol_name,
			  struct ltt_event *event)
{
	return -ENOSYS;
}

static inline
void lttng_ftrace_unregister(struct ltt_event *event)
{
}
#endif
#endif /* _LTT_EVENTS_H */
Commit	Line	Data
	1	#ifndef _LTT_EVENTS_H
	2	#define _LTT_EVENTS_H
	3
	4	/*
	5	* ltt-events.h
	6	*
	7	* Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* Holds LTTng per-session event registry.
	10	*/
	11
	12	#include <linux/list.h>
	13	#include <linux/uuid.h>
	14	#include <linux/kprobes.h>
	15	#include "ltt-debugfs-abi.h"
	16
	17	struct ltt_channel;
	18	struct ltt_session;
	19	struct lib_ring_buffer_ctx;
	20	struct perf_event;
	21	struct perf_event_attr;
	22
	23	/* Type description */
	24
	25	/* Update the astract_types name table in lttng-types.c along with this enum */
	26	enum abstract_types {
	27	atype_integer,
	28	atype_enum,
	29	atype_array,
	30	atype_sequence,
	31	atype_string,
	32	NR_ABSTRACT_TYPES,
	33	};
	34
	35	/* Update the string_encodings name table in lttng-types.c along with this enum */
	36	enum lttng_string_encodings {
	37	lttng_encode_none = 0,
	38	lttng_encode_UTF8 = 1,
	39	lttng_encode_ASCII = 2,
	40	NR_STRING_ENCODINGS,
	41	};
	42
	43	struct lttng_enum_entry {
	44	unsigned long long start, end; /* start and end are inclusive */
	45	const char *string;
	46	};
	47
	48	#define __type_integer(_type, _byte_order, _base) \
	49	{ \
	50	.atype = atype_integer, \
	51	.u.basic.integer = \
	52	{ \
	53	.size = sizeof(_type) * CHAR_BIT, \
	54	.alignment = ltt_alignof(_type) * CHAR_BIT, \
	55	.signedness = is_signed_type(_type), \
	56	.reverse_byte_order = _byte_order != __BYTE_ORDER, \
	57	.base = _base, \
	58	.encoding = lttng_encode_none, \
	59	}, \
	60	} \
	61
	62	struct lttng_integer_type {
	63	unsigned int size; /* in bits */
	64	unsigned short alignment; /* in bits */
	65	unsigned int signedness:1;
	66	unsigned int reverse_byte_order:1;
	67	unsigned int base; /* 2, 8, 10, 16, for pretty print */
	68	enum lttng_string_encodings encoding;
	69	};
	70
	71	union _lttng_basic_type {
	72	struct lttng_integer_type integer;
	73	struct {
	74	const char *name;
	75	} enumeration;
	76	struct {
	77	enum lttng_string_encodings encoding;
	78	} string;
	79	};
	80
	81	struct lttng_basic_type {
	82	enum abstract_types atype;
	83	union {
	84	union _lttng_basic_type basic;
	85	} u;
	86	};
	87
	88	struct lttng_type {
	89	enum abstract_types atype;
	90	union {
	91	union _lttng_basic_type basic;
	92	struct {
	93	struct lttng_basic_type elem_type;
	94	unsigned int length; /* num. elems. */
	95	} array;
	96	struct {
	97	struct lttng_basic_type length_type;
	98	struct lttng_basic_type elem_type;
	99	} sequence;
	100	} u;
	101	};
	102
	103	struct lttng_enum {
	104	const char *name;
	105	struct lttng_type container_type;
	106	const struct lttng_enum_entry *entries;
	107	unsigned int len;
	108	};
	109
	110	/* Event field description */
	111
	112	struct lttng_event_field {
	113	const char *name;
	114	struct lttng_type type;
	115	};
	116
	117	struct lttng_ctx_field {
	118	const char *name;
	119	struct lttng_type type;
	120	void *callback;
	121	union {
	122	struct {
	123	struct perf_event *e; / per-cpu array */
	124	struct list_head head;
	125	struct perf_event_attr *attr;
	126	} perf_counter;
	127	} u;
	128	};
	129
	130	struct lttng_ctx {
	131	struct lttng_ctx_field *fields;
	132	unsigned int nr_fields;
	133	unsigned int allocated_fields;
	134	};
	135
	136	struct lttng_event_desc {
	137	const char *name;
	138	void *probe_callback;
	139	const struct lttng_event_ctx ctx; / context */
	140	const struct lttng_event_field fields; / event payload */
	141	unsigned int nr_fields;
	142	};
	143
	144	struct lttng_probe_desc {
	145	const struct lttng_event_desc *event_desc;
	146	unsigned int nr_events;
	147	struct list_head head; /* chain registered probes */
	148	};
	149
	150	/*
	151	* ltt_event structure is referred to by the tracing fast path. It must be
	152	* kept small.
	153	*/
	154	struct ltt_event {
	155	unsigned int id;
	156	struct ltt_channel *chan;
	157	const struct lttng_event_desc *desc;
	158	void *filter;
	159	enum lttng_kernel_instrumentation instrumentation;
	160	union {
	161	struct {
	162	struct kprobe kp;
	163	char *symbol_name;
	164	} kprobe;
	165	struct {
	166	char *symbol_name;
	167	} ftrace;
	168	} u;
	169	struct list_head list; /* Event list */
	170	int metadata_dumped:1;
	171	};
	172
	173	struct ltt_channel_ops {
	174	struct channel (channel_create)(const char *name,
	175	struct ltt_channel *ltt_chan,
	176	void *buf_addr,
	177	size_t subbuf_size, size_t num_subbuf,
	178	unsigned int switch_timer_interval,
	179	unsigned int read_timer_interval);
	180	void (channel_destroy)(struct channel chan);
	181	struct lib_ring_buffer (buffer_read_open)(struct channel *chan);
	182	void (buffer_read_close)(struct lib_ring_buffer buf);
	183	int (event_reserve)(struct lib_ring_buffer_ctx ctx,
	184	uint16_t event_id);
	185	void (event_commit)(struct lib_ring_buffer_ctx ctx);
	186	void (event_write)(struct lib_ring_buffer_ctx ctx, const void *src,
	187	size_t len);
	188	/*
	189	* packet_avail_size returns the available size in the current
	190	* packet. Note that the size returned is only a hint, since it
	191	* may change due to concurrent writes.
	192	*/
	193	size_t (packet_avail_size)(struct channel chan);
	194	wait_queue_head_t (get_reader_wait_queue)(struct ltt_channel *chan);
	195	};
	196
	197	struct ltt_channel {
	198	unsigned int id;
	199	struct channel chan; / Channel buffers */
	200	/* Event ID management */
	201	struct ltt_session *session;
	202	struct file file; / File associated to channel */
	203	unsigned int free_event_id; /* Next event ID to allocate */
	204	struct list_head list; /* Channel list */
	205	wait_queue_head_t notify_wait; /* Channel addition notif. waitqueue */
	206	struct ltt_channel_ops *ops;
	207	int header_type; /* 0: unset, 1: compact, 2: large */
	208	int metadata_dumped:1;
	209	};
	210
	211	struct ltt_session {
	212	int active; /* Is trace session active ? */
	213	struct file file; / File associated to session */
	214	struct ltt_channel metadata; / Metadata channel */
	215	struct list_head chan; /* Channel list head */
	216	struct list_head events; /* Event list head */
	217	struct list_head list; /* Session list */
	218	unsigned int free_chan_id; /* Next chan ID to allocate */
	219	uuid_le uuid; /* Trace session unique ID */
	220	int metadata_dumped:1;
	221	};
	222
	223	struct ltt_transport {
	224	char *name;
	225	struct module *owner;
	226	struct list_head node;
	227	struct ltt_channel_ops ops;
	228	};
	229
	230	struct ltt_session *ltt_session_create(void);
	231	int ltt_session_start(struct ltt_session *session);
	232	int ltt_session_stop(struct ltt_session *session);
	233	void ltt_session_destroy(struct ltt_session *session);
	234
	235	struct ltt_channel ltt_channel_create(struct ltt_session session,
	236	const char *transport_name,
	237	void *buf_addr,
	238	size_t subbuf_size, size_t num_subbuf,
	239	unsigned int switch_timer_interval,
	240	unsigned int read_timer_interval);
	241	struct ltt_channel ltt_global_channel_create(struct ltt_session session,
	242	int overwrite, void *buf_addr,
	243	size_t subbuf_size, size_t num_subbuf,
	244	unsigned int switch_timer_interval,
	245	unsigned int read_timer_interval);
	246
	247	struct ltt_event ltt_event_create(struct ltt_channel chan,
	248	struct lttng_kernel_event *event_param,
	249	void *filter);
	250
	251	void ltt_transport_register(struct ltt_transport *transport);
	252	void ltt_transport_unregister(struct ltt_transport *transport);
	253
	254	int ltt_debugfs_abi_init(void);
	255	void ltt_debugfs_abi_exit(void);
	256
	257	int ltt_probe_register(struct lttng_probe_desc *desc);
	258	void ltt_probe_unregister(struct lttng_probe_desc *desc);
	259	const struct lttng_event_desc ltt_event_get(const char name);
	260	void ltt_event_put(const struct lttng_event_desc *desc);
	261	int ltt_probes_init(void);
	262	void ltt_probes_exit(void);
	263
	264	#ifdef CONFIG_KPROBES
	265	int lttng_kprobes_register(const char *name,
	266	const char *symbol_name,
	267	uint64_t offset,
	268	uint64_t addr,
	269	struct ltt_event *event);
	270	void lttng_kprobes_unregister(struct ltt_event *event);
	271	#else
	272	static inline
	273	int lttng_kprobes_register(const char *name,
	274	const char *symbol_name,
	275	uint64_t offset,
	276	uint64_t addr,
	277	struct ltt_event *event)
	278	{
	279	return -ENOSYS;
	280	}
	281
	282	static inline
	283	void lttng_kprobes_unregister(struct ltt_event *event)
	284	{
	285	}
	286	#endif
	287
	288	#ifdef CONFIG_DYNAMIC_FTRACE
	289	int lttng_ftrace_register(const char *name,
	290	const char *symbol_name,
	291	struct ltt_event *event);
	292	void lttng_ftrace_unregister(struct ltt_event *event);
	293	#else
	294	static inline
	295	int lttng_ftrace_register(const char *name,
	296	const char *symbol_name,
	297	struct ltt_event *event)
	298	{
	299	return -ENOSYS;
	300	}
	301
	302	static inline
	303	void lttng_ftrace_unregister(struct ltt_event *event)
	304	{
	305	}
	306	#endif
	307	#endif /* _LTT_EVENTS_H */