[lttng-modules.git] / ltt-tracer.h

/*
 * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
 *
 * This contains the definitions for the Linux Trace Toolkit tracer.
 *
 * Dual LGPL v2.1/GPL v2 license.
 */

#ifndef _LTT_TRACER_H
#define _LTT_TRACER_H

#include <stdarg.h>
#include <linux/types.h>
#include <linux/limits.h>
#include <linux/list.h>
#include <linux/cache.h>
#include <linux/timex.h>
#include <linux/wait.h>
#include <asm/atomic.h>
#include <asm/local.h>

#include "wrapper/trace-clock.h"
#include "ltt-tracer-core.h"
#include "ltt-events.h"

/* Number of bytes to log with a read/write event */
#define LTT_LOG_RW_SIZE			32L

/* Maximum number of callbacks per marker */
#define LTT_NR_CALLBACKS	10

struct ltt_serialize_closure;

/* Serialization callback */
typedef size_t (*ltt_serialize_cb)(struct lib_ring_buffer *buf,
				   size_t buf_offset,
				   struct ltt_serialize_closure *closure,
				   void *serialize_private,
				   unsigned int stack_pos_ctx,
				   int *largest_align,
				   const char *fmt, va_list *args);

struct ltt_serialize_closure {
	ltt_serialize_cb *callbacks;
	long cb_args[LTT_NR_CALLBACKS];
	unsigned int cb_idx;
};

size_t ltt_serialize_data(struct lib_ring_buffer *buf, size_t buf_offset,
			  struct ltt_serialize_closure *closure,
			  void *serialize_private, unsigned int stack_pos_ctx,
			  int *largest_align, const char *fmt, va_list *args);

enum ltt_channels {
	LTT_CHANNEL_METADATA,
	LTT_CHANNEL_FD_STATE,
	LTT_CHANNEL_GLOBAL_STATE,
	LTT_CHANNEL_IRQ_STATE,
	LTT_CHANNEL_MODULE_STATE,
	LTT_CHANNEL_NETIF_STATE,
	LTT_CHANNEL_SOFTIRQ_STATE,
	LTT_CHANNEL_SWAP_STATE,
	LTT_CHANNEL_SYSCALL_STATE,
	LTT_CHANNEL_TASK_STATE,
	LTT_CHANNEL_VM_STATE,
	LTT_CHANNEL_FS,
	LTT_CHANNEL_INPUT,
	LTT_CHANNEL_IPC,
	LTT_CHANNEL_KERNEL,
	LTT_CHANNEL_MM,
	LTT_CHANNEL_RCU,
	LTT_CHANNEL_DEFAULT,
};

/*
 * Hardcoded event headers
 *
 * event header for a trace with active heartbeat : 27 bits timestamps
 *
 * headers are 32-bits aligned. In order to insure such alignment, a dynamic per
 * trace alignment value must be done.
 *
 * Remember that the C compiler does align each member on the boundary
 * equivalent to their own size.
 *
 * As relay subbuffers are aligned on pages, we are sure that they are 4 and 8
 * bytes aligned, so the buffer header and trace header are aligned.
 *
 * Event headers are aligned depending on the trace alignment option.
 *
 * Note using C structure bitfields for cross-endianness and portability
 * concerns.
 */

#define LTT_RESERVED_EVENTS	3
#define LTT_EVENT_BITS		5
#define LTT_FREE_EVENTS		((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS)
#define LTT_TSC_BITS		27
#define LTT_TSC_MASK		((1 << LTT_TSC_BITS) - 1)

struct event_header {
	u32 id_time;		/* 5 bits event id (MSB); 27 bits time (LSB) */
};

/* Reservation flags */
#define	LTT_RFLAG_ID			(1 << 0)
#define	LTT_RFLAG_ID_SIZE		(1 << 1)
#define	LTT_RFLAG_ID_SIZE_TSC		(1 << 2)

#define LTT_MAX_SMALL_SIZE		0xFFFFU

/*
 * We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
 * specifically with CPU frequency scaling someday, so using an interpolation
 * between the start and end of buffer values is not flexible enough. Using an
 * immediate frequency value permits to calculate directly the times for parts
 * of a buffer that would be before a frequency change.
 *
 * Keep the natural field alignment for _each field_ within this structure if
 * you ever add/remove a field from this header. Packed attribute is not used
 * because gcc generates poor code on at least powerpc and mips. Don't ever
 * let gcc add padding between the structure elements.
 */
struct packet_header {
	uint32_t magic;			/*
					 * Trace magic number.
					 * contains endianness information.
					 */
	uint8_t trace_uuid[16];
	uint32_t stream_id;
	uint64_t timestamp_begin;	/* Cycle count at subbuffer start */
	uint64_t timestamp_end;	/* Cycle count at subbuffer end */
	uint32_t content_size;		/* Size of data in subbuffer */
	uint32_t packet_size;		/* Subbuffer size (include padding) */
	uint32_t events_lost;		/*
					 * Events lost in this subbuffer since
					 * the beginning of the trace.
					 * (may overflow)
					 */
	/* TODO: move to metadata */
#if 0
	uint8_t major_version;
	uint8_t minor_version;
	uint8_t arch_size;		/* Architecture pointer size */
	uint8_t alignment;		/* LTT data alignment */
	uint64_t start_time_sec;	/* NTP-corrected start time */
	uint64_t start_time_usec;
	uint64_t start_freq;		/*
					 * Frequency at trace start,
					 * used all along the trace.
					 */
	uint32_t freq_scale;		/* Frequency scaling (divisor) */
#endif //0
	uint8_t header_end[0];		/* End of header */
};

static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
{
	return trace_clock_read64();
}

/*
 * record_header_size - Calculate the header size and padding necessary.
 * @config: ring buffer instance configuration
 * @chan: channel
 * @offset: offset in the write buffer
 * @data_size: size of the payload
 * @pre_header_padding: padding to add before the header (output)
 * @rflags: reservation flags
 * @ctx: reservation context
 *
 * Returns the event header size (including padding).
 *
 * Important note :
 * The event header must be 32-bits. The total offset calculated here :
 *
 * Alignment of header struct on 32 bits (min arch size, header size)
 * + sizeof(header struct)  (32-bits)
 * + (opt) u16 (ext. event id)
 * + (opt) u16 (event_size)
 *             (if event_size == LTT_MAX_SMALL_SIZE, has ext. event size)
 * + (opt) u32 (ext. event size)
 * + (opt) u64 full TSC (aligned on min(64-bits, arch size))
 *
 * The payload must itself determine its own alignment from the biggest type it
 * contains.
 */
static __inline__
unsigned char record_header_size(const struct lib_ring_buffer_config *config,
				 struct channel *chan, size_t offset,
				 size_t data_size, size_t *pre_header_padding,
				 unsigned int rflags,
				 struct lib_ring_buffer_ctx *ctx)
{
	size_t orig_offset = offset;
	size_t padding;

	BUILD_BUG_ON(sizeof(struct event_header) != sizeof(u32));

	padding = lib_ring_buffer_align(offset,
					sizeof(struct event_header));
	offset += padding;
	offset += sizeof(struct event_header);

	if (unlikely(rflags)) {
		switch (rflags) {
		case LTT_RFLAG_ID_SIZE_TSC:
			offset += sizeof(u16) + sizeof(u16);
			if (data_size >= LTT_MAX_SMALL_SIZE)
				offset += sizeof(u32);
			offset += lib_ring_buffer_align(offset, sizeof(u64));
			offset += sizeof(u64);
			break;
		case LTT_RFLAG_ID_SIZE:
			offset += sizeof(u16) + sizeof(u16);
			if (data_size >= LTT_MAX_SMALL_SIZE)
				offset += sizeof(u32);
			break;
		case LTT_RFLAG_ID:
			offset += sizeof(u16);
			break;
		}
	}

	*pre_header_padding = padding;
	return offset - orig_offset;
}

#include "wrapper/ringbuffer/api.h"

extern
void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
				 struct lib_ring_buffer_ctx *ctx,
				 u16 eID, u32 event_size);

/*
 * ltt_write_event_header
 *
 * Writes the event header to the offset (already aligned on 32-bits).
 *
 * @config: ring buffer instance configuration
 * @ctx: reservation context
 * @eID : event ID
 * @event_size : size of the event, excluding the event header.
 */
static __inline__
void ltt_write_event_header(const struct lib_ring_buffer_config *config,
			    struct lib_ring_buffer_ctx *ctx,
			    u16 eID, u32 event_size)
{
	struct event_header header;

	if (unlikely(ctx->rflags))
		goto slow_path;

	header.id_time = eID << LTT_TSC_BITS;
	header.id_time |= (u32)ctx->tsc & LTT_TSC_MASK;
	lib_ring_buffer_write(config, ctx, &header, sizeof(header));

slow_path:
	ltt_write_event_header_slow(config, ctx, eID, event_size);
}

/* Tracer properties */
#define CTF_MAGIC_NUMBER		0xC1FC1FC1
#define LTT_TRACER_VERSION_MAJOR	3
#define LTT_TRACER_VERSION_MINOR	0

/**
 * ltt_write_trace_header - Write trace header
 * @priv: Private data (struct trace)
 * @header: Memory address where the information must be written to
 */
static __inline__
void write_trace_header(const struct lib_ring_buffer_config *config,
			struct packet_header *header)
{
	header->magic = CTF_MAGIC_NUMBER;
#if 0
	/* TODO: move start time to metadata */
	header->major_version = LTT_TRACER_VERSION_MAJOR;
	header->minor_version = LTT_TRACER_VERSION_MINOR;
	header->arch_size = sizeof(void *);
	header->alignment = lib_ring_buffer_get_alignment(config);
	header->start_time_sec = ltt_chan->session->start_time.tv_sec;
	header->start_time_usec = ltt_chan->session->start_time.tv_usec;
	header->start_freq = ltt_chan->session->start_freq;
	header->freq_scale = ltt_chan->session->freq_scale;
#endif //0
}

/*
 * Size reserved for high priority events (interrupts, NMI, BH) at the end of a
 * nearly full buffer. User space won't use this last amount of space when in
 * blocking mode. This space also includes the event header that would be
 * written by this user space event.
 */
#define LTT_RESERVE_CRITICAL		4096

/* Register and unregister function pointers */

enum ltt_module_function {
	LTT_FUNCTION_RUN_FILTER,
	LTT_FUNCTION_FILTER_CONTROL,
	LTT_FUNCTION_STATEDUMP
};

extern int ltt_module_register(enum ltt_module_function name, void *function,
			       struct module *owner);
extern void ltt_module_unregister(enum ltt_module_function name);

/* Exported control function */

void ltt_core_register(int (*function)(u8, void *));

void ltt_core_unregister(void);

extern
void ltt_statedump_register_kprobes_dump(void (*callback)(void *call_data));
extern
void ltt_statedump_unregister_kprobes_dump(void (*callback)(void *call_data));

extern void ltt_dump_softirq_vec(void *call_data);

#ifdef CONFIG_HAVE_LTT_DUMP_TABLES
extern void ltt_dump_sys_call_table(void *call_data);
extern void ltt_dump_idt_table(void *call_data);
#else
static inline void ltt_dump_sys_call_table(void *call_data)
{
}

static inline void ltt_dump_idt_table(void *call_data)
{
}
#endif

#endif /* _LTT_TRACER_H */
Commit	Line	Data
1c8284eb MD	1	/*
	2	* Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
	3	*
	4	* This contains the definitions for the Linux Trace Toolkit tracer.
	5	*
	6	* Dual LGPL v2.1/GPL v2 license.
	7	*/
	8
	9	#ifndef _LTT_TRACER_H
	10	#define _LTT_TRACER_H
	11
	12	#include <stdarg.h>
	13	#include <linux/types.h>
	14	#include <linux/limits.h>
	15	#include <linux/list.h>
	16	#include <linux/cache.h>
1c8284eb MD	17	#include <linux/timex.h>
1c8284eb MD	18	#include <linux/wait.h>
1c8284eb MD	19	#include <asm/atomic.h>
	20	#include <asm/local.h>
	21
f3bc08c5	22	#include "wrapper/trace-clock.h"
1c8284eb	23	#include "ltt-tracer-core.h"
1c25284c	24	#include "ltt-events.h"
1c8284eb MD	25
	26	/* Number of bytes to log with a read/write event */
	27	#define LTT_LOG_RW_SIZE 32L
	28
1c8284eb MD	29	/* Maximum number of callbacks per marker */
	30	#define LTT_NR_CALLBACKS 10
	31
11b5a3c2 MD	32	struct ltt_serialize_closure;
	33
	34	/* Serialization callback */
	35	typedef size_t (ltt_serialize_cb)(struct lib_ring_buffer buf,
	36	size_t buf_offset,
	37	struct ltt_serialize_closure *closure,
	38	void *serialize_private,
	39	unsigned int stack_pos_ctx,
	40	int *largest_align,
	41	const char fmt, va_list args);
	42
1c8284eb MD	43	struct ltt_serialize_closure {
	44	ltt_serialize_cb *callbacks;
	45	long cb_args[LTT_NR_CALLBACKS];
	46	unsigned int cb_idx;
	47	};
	48
11b5a3c2	49	size_t ltt_serialize_data(struct lib_ring_buffer *buf, size_t buf_offset,
1c8284eb MD	50	struct ltt_serialize_closure *closure,
	51	void *serialize_private, unsigned int stack_pos_ctx,
	52	int largest_align, const char fmt, va_list *args);
	53
1c8284eb MD	54	enum ltt_channels {
	55	LTT_CHANNEL_METADATA,
	56	LTT_CHANNEL_FD_STATE,
	57	LTT_CHANNEL_GLOBAL_STATE,
	58	LTT_CHANNEL_IRQ_STATE,
	59	LTT_CHANNEL_MODULE_STATE,
	60	LTT_CHANNEL_NETIF_STATE,
	61	LTT_CHANNEL_SOFTIRQ_STATE,
	62	LTT_CHANNEL_SWAP_STATE,
	63	LTT_CHANNEL_SYSCALL_STATE,
	64	LTT_CHANNEL_TASK_STATE,
	65	LTT_CHANNEL_VM_STATE,
	66	LTT_CHANNEL_FS,
	67	LTT_CHANNEL_INPUT,
	68	LTT_CHANNEL_IPC,
	69	LTT_CHANNEL_KERNEL,
	70	LTT_CHANNEL_MM,
	71	LTT_CHANNEL_RCU,
	72	LTT_CHANNEL_DEFAULT,
	73	};
	74
7514523f MD	75	/*
7514523f MD	76	* Hardcoded event headers
1c8284eb MD	77	*
	78	* event header for a trace with active heartbeat : 27 bits timestamps
	79	*
	80	* headers are 32-bits aligned. In order to insure such alignment, a dynamic per
	81	* trace alignment value must be done.
	82	*
	83	* Remember that the C compiler does align each member on the boundary
	84	* equivalent to their own size.
	85	*
	86	* As relay subbuffers are aligned on pages, we are sure that they are 4 and 8
	87	* bytes aligned, so the buffer header and trace header are aligned.
	88	*
	89	* Event headers are aligned depending on the trace alignment option.
	90	*
	91	* Note using C structure bitfields for cross-endianness and portability
	92	* concerns.
	93	*/
	94
	95	#define LTT_RESERVED_EVENTS 3
	96	#define LTT_EVENT_BITS 5
	97	#define LTT_FREE_EVENTS ((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS)
	98	#define LTT_TSC_BITS 27
	99	#define LTT_TSC_MASK ((1 << LTT_TSC_BITS) - 1)
	100
7514523f	101	struct event_header {
1c8284eb MD	102	u32 id_time; /* 5 bits event id (MSB); 27 bits time (LSB) */
	103	};
	104
	105	/* Reservation flags */
	106	#define LTT_RFLAG_ID (1 << 0)
	107	#define LTT_RFLAG_ID_SIZE (1 << 1)
	108	#define LTT_RFLAG_ID_SIZE_TSC (1 << 2)
	109
	110	#define LTT_MAX_SMALL_SIZE 0xFFFFU
	111
	112	/*
	113	* We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
	114	* specifically with CPU frequency scaling someday, so using an interpolation
	115	* between the start and end of buffer values is not flexible enough. Using an
	116	* immediate frequency value permits to calculate directly the times for parts
	117	* of a buffer that would be before a frequency change.
	118	*
	119	* Keep the natural field alignment for _each field_ within this structure if
	120	* you ever add/remove a field from this header. Packed attribute is not used
	121	* because gcc generates poor code on at least powerpc and mips. Don't ever
	122	* let gcc add padding between the structure elements.
	123	*/
1c25284c MD	124	struct packet_header {
1c25284c MD	125	uint32_t magic; /*
1c8284eb MD	126	* Trace magic number.
	127	* contains endianness information.
	128	*/
1c25284c MD	129	uint8_t trace_uuid[16];
	130	uint32_t stream_id;
	131	uint64_t timestamp_begin; /* Cycle count at subbuffer start */
	132	uint64_t timestamp_end; /* Cycle count at subbuffer end */
	133	uint32_t content_size; /* Size of data in subbuffer */
	134	uint32_t packet_size; /* Subbuffer size (include padding) */
	135	uint32_t events_lost; /*
	136	* Events lost in this subbuffer since
	137	* the beginning of the trace.
	138	* (may overflow)
	139	*/
	140	/* TODO: move to metadata */
	141	#if 0
1c8284eb MD	142	uint8_t major_version;
	143	uint8_t minor_version;
	144	uint8_t arch_size; /* Architecture pointer size */
	145	uint8_t alignment; /* LTT data alignment */
	146	uint64_t start_time_sec; /* NTP-corrected start time */
	147	uint64_t start_time_usec;
	148	uint64_t start_freq; /*
	149	* Frequency at trace start,
	150	* used all along the trace.
	151	*/
	152	uint32_t freq_scale; /* Frequency scaling (divisor) */
1c25284c	153	#endif //0
1c8284eb MD	154	uint8_t header_end[0]; /* End of header */
	155	};
	156
7514523f	157	static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
1c8284eb	158	{
7514523f	159	return trace_clock_read64();
1c8284eb MD	160	}
	161
	162	/*
7514523f MD	163	* record_header_size - Calculate the header size and padding necessary.
	164	* @config: ring buffer instance configuration
	165	* @chan: channel
	166	* @offset: offset in the write buffer
	167	* @data_size: size of the payload
	168	* @pre_header_padding: padding to add before the header (output)
	169	* @rflags: reservation flags
	170	* @ctx: reservation context
1c8284eb	171	*
7514523f	172	* Returns the event header size (including padding).
1c8284eb MD	173	*
	174	* Important note :
	175	* The event header must be 32-bits. The total offset calculated here :
	176	*
	177	* Alignment of header struct on 32 bits (min arch size, header size)
	178	* + sizeof(header struct) (32-bits)
	179	* + (opt) u16 (ext. event id)
	180	* + (opt) u16 (event_size)
	181	* (if event_size == LTT_MAX_SMALL_SIZE, has ext. event size)
	182	* + (opt) u32 (ext. event size)
	183	* + (opt) u64 full TSC (aligned on min(64-bits, arch size))
	184	*
	185	* The payload must itself determine its own alignment from the biggest type it
	186	* contains.
7514523f	187	*/
1c8284eb	188	static __inline__
7514523f MD	189	unsigned char record_header_size(const struct lib_ring_buffer_config *config,
	190	struct channel *chan, size_t offset,
	191	size_t data_size, size_t *pre_header_padding,
	192	unsigned int rflags,
	193	struct lib_ring_buffer_ctx *ctx)
1c8284eb MD	194	{
	195	size_t orig_offset = offset;
	196	size_t padding;
	197
7514523f	198	BUILD_BUG_ON(sizeof(struct event_header) != sizeof(u32));
1c8284eb	199
6db3d13b	200	padding = lib_ring_buffer_align(offset,
7514523f	201	sizeof(struct event_header));
1c8284eb	202	offset += padding;
7514523f	203	offset += sizeof(struct event_header);
1c8284eb MD	204
	205	if (unlikely(rflags)) {
	206	switch (rflags) {
	207	case LTT_RFLAG_ID_SIZE_TSC:
	208	offset += sizeof(u16) + sizeof(u16);
	209	if (data_size >= LTT_MAX_SMALL_SIZE)
	210	offset += sizeof(u32);
9c5653d5	211	offset += lib_ring_buffer_align(offset, sizeof(u64));
1c8284eb MD	212	offset += sizeof(u64);
	213	break;
	214	case LTT_RFLAG_ID_SIZE:
	215	offset += sizeof(u16) + sizeof(u16);
	216	if (data_size >= LTT_MAX_SMALL_SIZE)
	217	offset += sizeof(u32);
	218	break;
	219	case LTT_RFLAG_ID:
	220	offset += sizeof(u16);
	221	break;
	222	}
	223	}
	224
7514523f	225	*pre_header_padding = padding;
1c8284eb MD	226	return offset - orig_offset;
	227	}
	228
f3bc08c5	229	#include "wrapper/ringbuffer/api.h"
7514523f	230
1c8284eb	231	extern
1c25284c MD	232	void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
	233	struct lib_ring_buffer_ctx *ctx,
	234	u16 eID, u32 event_size);
1c8284eb MD	235
	236	/*
	237	* ltt_write_event_header
	238	*
	239	* Writes the event header to the offset (already aligned on 32-bits).
	240	*
7514523f MD	241	* @config: ring buffer instance configuration
7514523f MD	242	* @ctx: reservation context
1c8284eb MD	243	* @eID : event ID
1c8284eb MD	244	* @event_size : size of the event, excluding the event header.
1c8284eb MD	245	*/
1c8284eb MD	246	static __inline__
7514523f MD	247	void ltt_write_event_header(const struct lib_ring_buffer_config *config,
	248	struct lib_ring_buffer_ctx *ctx,
	249	u16 eID, u32 event_size)
1c8284eb	250	{
7514523f	251	struct event_header header;
1c8284eb	252
7514523f	253	if (unlikely(ctx->rflags))
1c8284eb MD	254	goto slow_path;
	255
	256	header.id_time = eID << LTT_TSC_BITS;
7514523f MD	257	header.id_time \|= (u32)ctx->tsc & LTT_TSC_MASK;
7514523f MD	258	lib_ring_buffer_write(config, ctx, &header, sizeof(header));
1c8284eb MD	259
1c8284eb MD	260	slow_path:
7514523f	261	ltt_write_event_header_slow(config, ctx, eID, event_size);
1c8284eb MD	262	}
1c8284eb MD	263
1c8284eb	264	/* Tracer properties */
1c25284c MD	265	#define CTF_MAGIC_NUMBER 0xC1FC1FC1
	266	#define LTT_TRACER_VERSION_MAJOR 3
	267	#define LTT_TRACER_VERSION_MINOR 0
1c8284eb MD	268
	269	/**
	270	* ltt_write_trace_header - Write trace header
7514523f	271	* @priv: Private data (struct trace)
1c8284eb MD	272	* @header: Memory address where the information must be written to
	273	*/
	274	static __inline__
1c25284c MD	275	void write_trace_header(const struct lib_ring_buffer_config *config,
1c25284c MD	276	struct packet_header *header)
1c8284eb	277	{
1c25284c MD	278	header->magic = CTF_MAGIC_NUMBER;
	279	#if 0
	280	/* TODO: move start time to metadata */
1c8284eb MD	281	header->major_version = LTT_TRACER_VERSION_MAJOR;
	282	header->minor_version = LTT_TRACER_VERSION_MINOR;
	283	header->arch_size = sizeof(void *);
1c25284c MD	284	header->alignment = lib_ring_buffer_get_alignment(config);
	285	header->start_time_sec = ltt_chan->session->start_time.tv_sec;
	286	header->start_time_usec = ltt_chan->session->start_time.tv_usec;
	287	header->start_freq = ltt_chan->session->start_freq;
	288	header->freq_scale = ltt_chan->session->freq_scale;
	289	#endif //0
1c8284eb MD	290	}
	291
	292	/*
	293	* Size reserved for high priority events (interrupts, NMI, BH) at the end of a
	294	* nearly full buffer. User space won't use this last amount of space when in
	295	* blocking mode. This space also includes the event header that would be
	296	* written by this user space event.
	297	*/
	298	#define LTT_RESERVE_CRITICAL 4096
	299
	300	/* Register and unregister function pointers */
	301
	302	enum ltt_module_function {
	303	LTT_FUNCTION_RUN_FILTER,
	304	LTT_FUNCTION_FILTER_CONTROL,
	305	LTT_FUNCTION_STATEDUMP
	306	};
	307
	308	extern int ltt_module_register(enum ltt_module_function name, void *function,
	309	struct module *owner);
	310	extern void ltt_module_unregister(enum ltt_module_function name);
	311
1c8284eb MD	312	/* Exported control function */
1c8284eb MD	313
1c8284eb MD	314	void ltt_core_register(int (function)(u8, void ));
	315
	316	void ltt_core_unregister(void);
	317
1c8284eb MD	318	extern
	319	void ltt_statedump_register_kprobes_dump(void (callback)(void call_data));
	320	extern
	321	void ltt_statedump_unregister_kprobes_dump(void (callback)(void call_data));
	322
	323	extern void ltt_dump_softirq_vec(void *call_data);
	324
f277b4c1	325	#ifdef CONFIG_HAVE_LTT_DUMP_TABLES
1c8284eb MD	326	extern void ltt_dump_sys_call_table(void *call_data);
1c8284eb MD	327	extern void ltt_dump_idt_table(void *call_data);
f277b4c1 MD	328	#else
	329	static inline void ltt_dump_sys_call_table(void *call_data)
	330	{
	331	}
	332
	333	static inline void ltt_dump_idt_table(void *call_data)
	334	{
	335	}
	336	#endif
1c8284eb	337
1c8284eb	338	#endif /* _LTT_TRACER_H */