[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"

#undef is_signed_type
#define is_signed_type(type)		(((type)(-1)) < 0)

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, _encoding)	\
	{							\
	    .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_##_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;
};

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 {
	struct lttng_event_field event_field;
	size_t (*get_size)(size_t offset);
	void (*record)(struct lttng_ctx_field *field,
		       struct lib_ring_buffer_ctx *ctx,
		       struct ltt_channel *chan);
	union {
		struct {
			struct perf_event **e;	/* per-cpu array */
			struct list_head head;
			struct perf_event_attr *attr;
		} perf_counter;
	} 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 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 module *owner;
};

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;
	struct lttng_ctx *ctx;
	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,
			     uint32_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 */
	struct lttng_ctx *ctx;
	/* 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 ? */
	int been_active;		/* Has trace session been 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);
struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx);
void lttng_destroy_context(struct lttng_ctx *ctx);
int lttng_add_pid_to_ctx(struct lttng_ctx **ctx);
int lttng_add_comm_to_ctx(struct lttng_ctx **ctx);

#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);
void lttng_kprobes_destroy_private(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)
{
}

static inline
void lttng_kprobes_destroy_private(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);
void lttng_ftrace_destroy_private(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)
{
}

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

extern const struct file_operations lttng_tracepoint_list_fops;

#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	#undef is_signed_type
	18	#define is_signed_type(type) (((type)(-1)) < 0)
	19
	20	struct ltt_channel;
	21	struct ltt_session;
	22	struct lib_ring_buffer_ctx;
	23	struct perf_event;
	24	struct perf_event_attr;
	25
	26	/* Type description */
	27
	28	/* Update the astract_types name table in lttng-types.c along with this enum */
	29	enum abstract_types {
	30	atype_integer,
	31	atype_enum,
	32	atype_array,
	33	atype_sequence,
	34	atype_string,
	35	NR_ABSTRACT_TYPES,
	36	};
	37
	38	/* Update the string_encodings name table in lttng-types.c along with this enum */
	39	enum lttng_string_encodings {
	40	lttng_encode_none = 0,
	41	lttng_encode_UTF8 = 1,
	42	lttng_encode_ASCII = 2,
	43	NR_STRING_ENCODINGS,
	44	};
	45
	46	struct lttng_enum_entry {
	47	unsigned long long start, end; /* start and end are inclusive */
	48	const char *string;
	49	};
	50
	51	#define __type_integer(_type, _byte_order, _base, _encoding) \
	52	{ \
	53	.atype = atype_integer, \
	54	.u.basic.integer = \
	55	{ \
	56	.size = sizeof(_type) * CHAR_BIT, \
	57	.alignment = ltt_alignof(_type) * CHAR_BIT, \
	58	.signedness = is_signed_type(_type), \
	59	.reverse_byte_order = _byte_order != __BYTE_ORDER, \
	60	.base = _base, \
	61	.encoding = lttng_encode_##_encoding, \
	62	}, \
	63	} \
	64
	65	struct lttng_integer_type {
	66	unsigned int size; /* in bits */
	67	unsigned short alignment; /* in bits */
	68	unsigned int signedness:1;
	69	unsigned int reverse_byte_order:1;
	70	unsigned int base; /* 2, 8, 10, 16, for pretty print */
	71	enum lttng_string_encodings encoding;
	72	};
	73
	74	union _lttng_basic_type {
	75	struct lttng_integer_type integer;
	76	struct {
	77	const char *name;
	78	} enumeration;
	79	struct {
	80	enum lttng_string_encodings encoding;
	81	} string;
	82	};
	83
	84	struct lttng_basic_type {
	85	enum abstract_types atype;
	86	union {
	87	union _lttng_basic_type basic;
	88	} u;
	89	};
	90
	91	struct lttng_type {
	92	enum abstract_types atype;
	93	union {
	94	union _lttng_basic_type basic;
	95	struct {
	96	struct lttng_basic_type elem_type;
	97	unsigned int length; /* num. elems. */
	98	} array;
	99	struct {
	100	struct lttng_basic_type length_type;
	101	struct lttng_basic_type elem_type;
	102	} sequence;
	103	} u;
	104	};
	105
	106	struct lttng_enum {
	107	const char *name;
	108	struct lttng_type container_type;
	109	const struct lttng_enum_entry *entries;
	110	unsigned int len;
	111	};
	112
	113	/* Event field description */
	114
	115	struct lttng_event_field {
	116	const char *name;
	117	struct lttng_type type;
	118	};
	119
	120	struct lttng_ctx_field {
	121	struct lttng_event_field event_field;
	122	size_t (*get_size)(size_t offset);
	123	void (record)(struct lttng_ctx_field field,
	124	struct lib_ring_buffer_ctx *ctx,
	125	struct ltt_channel *chan);
	126	union {
	127	struct {
	128	struct perf_event *e; / per-cpu array */
	129	struct list_head head;
	130	struct perf_event_attr *attr;
	131	} perf_counter;
	132	} u;
	133	void (destroy)(struct lttng_ctx_field field);
	134	};
	135
	136	struct lttng_ctx {
	137	struct lttng_ctx_field *fields;
	138	unsigned int nr_fields;
	139	unsigned int allocated_fields;
	140	};
	141
	142	struct lttng_event_desc {
	143	const char *name;
	144	void *probe_callback;
	145	const struct lttng_event_ctx ctx; / context */
	146	const struct lttng_event_field fields; / event payload */
	147	unsigned int nr_fields;
	148	struct module *owner;
	149	};
	150
	151	struct lttng_probe_desc {
	152	const struct lttng_event_desc *event_desc;
	153	unsigned int nr_events;
	154	struct list_head head; /* chain registered probes */
	155	};
	156
	157	/*
	158	* ltt_event structure is referred to by the tracing fast path. It must be
	159	* kept small.
	160	*/
	161	struct ltt_event {
	162	unsigned int id;
	163	struct ltt_channel *chan;
	164	const struct lttng_event_desc *desc;
	165	void *filter;
	166	struct lttng_ctx *ctx;
	167	enum lttng_kernel_instrumentation instrumentation;
	168	union {
	169	struct {
	170	struct kprobe kp;
	171	char *symbol_name;
	172	} kprobe;
	173	struct {
	174	char *symbol_name;
	175	} ftrace;
	176	} u;
	177	struct list_head list; /* Event list */
	178	int metadata_dumped:1;
	179	};
	180
	181	struct ltt_channel_ops {
	182	struct channel (channel_create)(const char *name,
	183	struct ltt_channel *ltt_chan,
	184	void *buf_addr,
	185	size_t subbuf_size, size_t num_subbuf,
	186	unsigned int switch_timer_interval,
	187	unsigned int read_timer_interval);
	188	void (channel_destroy)(struct channel chan);
	189	struct lib_ring_buffer (buffer_read_open)(struct channel *chan);
	190	void (buffer_read_close)(struct lib_ring_buffer buf);
	191	int (event_reserve)(struct lib_ring_buffer_ctx ctx,
	192	uint32_t event_id);
	193	void (event_commit)(struct lib_ring_buffer_ctx ctx);
	194	void (event_write)(struct lib_ring_buffer_ctx ctx, const void *src,
	195	size_t len);
	196	/*
	197	* packet_avail_size returns the available size in the current
	198	* packet. Note that the size returned is only a hint, since it
	199	* may change due to concurrent writes.
	200	*/
	201	size_t (packet_avail_size)(struct channel chan);
	202	wait_queue_head_t (get_reader_wait_queue)(struct ltt_channel *chan);
	203	};
	204
	205	struct ltt_channel {
	206	unsigned int id;
	207	struct channel chan; / Channel buffers */
	208	struct lttng_ctx *ctx;
	209	/* Event ID management */
	210	struct ltt_session *session;
	211	struct file file; / File associated to channel */
	212	unsigned int free_event_id; /* Next event ID to allocate */
	213	struct list_head list; /* Channel list */
	214	wait_queue_head_t notify_wait; /* Channel addition notif. waitqueue */
	215	struct ltt_channel_ops *ops;
	216	int header_type; /* 0: unset, 1: compact, 2: large */
	217	int metadata_dumped:1;
	218	};
	219
	220	struct ltt_session {
	221	int active; /* Is trace session active ? */
	222	int been_active; /* Has trace session been active ? */
	223	struct file file; / File associated to session */
	224	struct ltt_channel metadata; / Metadata channel */
	225	struct list_head chan; /* Channel list head */
	226	struct list_head events; /* Event list head */
	227	struct list_head list; /* Session list */
	228	unsigned int free_chan_id; /* Next chan ID to allocate */
	229	uuid_le uuid; /* Trace session unique ID */
	230	int metadata_dumped:1;
	231	};
	232
	233	struct ltt_transport {
	234	char *name;
	235	struct module *owner;
	236	struct list_head node;
	237	struct ltt_channel_ops ops;
	238	};
	239
	240	struct ltt_session *ltt_session_create(void);
	241	int ltt_session_start(struct ltt_session *session);
	242	int ltt_session_stop(struct ltt_session *session);
	243	void ltt_session_destroy(struct ltt_session *session);
	244
	245	struct ltt_channel ltt_channel_create(struct ltt_session session,
	246	const char *transport_name,
	247	void *buf_addr,
	248	size_t subbuf_size, size_t num_subbuf,
	249	unsigned int switch_timer_interval,
	250	unsigned int read_timer_interval);
	251	struct ltt_channel ltt_global_channel_create(struct ltt_session session,
	252	int overwrite, void *buf_addr,
	253	size_t subbuf_size, size_t num_subbuf,
	254	unsigned int switch_timer_interval,
	255	unsigned int read_timer_interval);
	256
	257	struct ltt_event ltt_event_create(struct ltt_channel chan,
	258	struct lttng_kernel_event *event_param,
	259	void *filter);
	260
	261	void ltt_transport_register(struct ltt_transport *transport);
	262	void ltt_transport_unregister(struct ltt_transport *transport);
	263
	264	int ltt_debugfs_abi_init(void);
	265	void ltt_debugfs_abi_exit(void);
	266
	267	int ltt_probe_register(struct lttng_probe_desc *desc);
	268	void ltt_probe_unregister(struct lttng_probe_desc *desc);
	269	const struct lttng_event_desc ltt_event_get(const char name);
	270	void ltt_event_put(const struct lttng_event_desc *desc);
	271	int ltt_probes_init(void);
	272	void ltt_probes_exit(void);
	273	struct lttng_ctx_field lttng_append_context(struct lttng_ctx *ctx);
	274	void lttng_destroy_context(struct lttng_ctx *ctx);
	275	int lttng_add_pid_to_ctx(struct lttng_ctx **ctx);
	276	int lttng_add_comm_to_ctx(struct lttng_ctx **ctx);
	277
	278	#ifdef CONFIG_KPROBES
	279	int lttng_kprobes_register(const char *name,
	280	const char *symbol_name,
	281	uint64_t offset,
	282	uint64_t addr,
	283	struct ltt_event *event);
	284	void lttng_kprobes_unregister(struct ltt_event *event);
	285	void lttng_kprobes_destroy_private(struct ltt_event *event);
	286	#else
	287	static inline
	288	int lttng_kprobes_register(const char *name,
	289	const char *symbol_name,
	290	uint64_t offset,
	291	uint64_t addr,
	292	struct ltt_event *event)
	293	{
	294	return -ENOSYS;
	295	}
	296
	297	static inline
	298	void lttng_kprobes_unregister(struct ltt_event *event)
	299	{
	300	}
	301
	302	static inline
	303	void lttng_kprobes_destroy_private(struct ltt_event *event)
	304	{
	305	}
	306	#endif
	307
	308	#ifdef CONFIG_DYNAMIC_FTRACE
	309	int lttng_ftrace_register(const char *name,
	310	const char *symbol_name,
	311	struct ltt_event *event);
	312	void lttng_ftrace_unregister(struct ltt_event *event);
	313	void lttng_ftrace_destroy_private(struct ltt_event *event);
	314	#else
	315	static inline
	316	int lttng_ftrace_register(const char *name,
	317	const char *symbol_name,
	318	struct ltt_event *event)
	319	{
	320	return -ENOSYS;
	321	}
	322
	323	static inline
	324	void lttng_ftrace_unregister(struct ltt_event *event)
	325	{
	326	}
	327
	328	static inline
	329	void lttng_ftrace_destroy_private(struct ltt_event *event)
	330	{
	331	}
	332	#endif
	333
	334	extern const struct file_operations lttng_tracepoint_list_fops;
	335
	336	#endif /* _LTT_EVENTS_H */