[ust.git] / libust / tracer.h

/*
 * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
 * Copyright (C) 2009 Pierre-Marc Fournier
 *
 * This contains the definitions for the Linux Trace Toolkit tracer.
 *
 * Ported to userspace by Pierre-Marc Fournier.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

#ifndef _LTT_TRACER_H
#define _LTT_TRACER_H

#include <sys/types.h>
#include <stdarg.h>
#include <ust/kernelcompat.h>
#include "channels.h"
#include "tracercore.h"
#include "tracerconst.h"
#include <ust/marker.h>
#include <ust/probe.h>

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

/* Interval (in jiffies) at which the LTT per-CPU timer fires */
#define LTT_PERCPU_TIMER_INTERVAL	1

#ifndef LTT_ARCH_TYPE
#define LTT_ARCH_TYPE			LTT_ARCH_TYPE_UNDEFINED
#endif

#ifndef LTT_ARCH_VARIANT
#define LTT_ARCH_VARIANT		LTT_ARCH_VARIANT_NONE
#endif

struct ltt_active_marker;

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

struct ltt_serialize_closure;
struct ltt_probe_private_data;

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

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

struct ltt_probe_private_data {
	struct ust_trace *trace;	/*
					 * Target trace, for metadata
					 * or statedump.
					 */
	ltt_serialize_cb serializer;	/*
					 * Serialization function override.
					 */
	void *serialize_private;	/*
					 * Private data for serialization
					 * functions.
					 */
};

enum ltt_channels {
	LTT_CHANNEL_METADATA,
	LTT_CHANNEL_UST,
};

struct ltt_active_marker {
	struct list_head node;		/* active markers list */
	const char *channel;
	const char *name;
	const char *format;
	struct ltt_available_probe *probe;
};

struct marker; //ust//
extern void ltt_vtrace(const struct marker *mdata, void *probe_data,
	struct registers *regs, void *call_data, const char *fmt, va_list *args);
extern void ltt_trace(const struct marker *mdata, void *probe_data,
	struct registers *regs, void *call_data, const char *fmt, ...);

/*
 * Unique ID assigned to each registered probe.
 */
enum marker_id {
	MARKER_ID_SET_MARKER_ID = 0,	/* Static IDs available (range 0-7) */
	MARKER_ID_SET_MARKER_FORMAT,
	MARKER_ID_COMPACT,		/* Compact IDs (range: 8-127)	    */
	MARKER_ID_DYNAMIC,		/* Dynamic IDs (range: 128-65535)   */
};

/* static ids 0-1 reserved for internal use. */
#define MARKER_CORE_IDS		2
static __inline__ enum marker_id marker_id_type(uint16_t id)
{
	if (id < MARKER_CORE_IDS)
		return (enum marker_id)id;
	else
		return MARKER_ID_DYNAMIC;
}

struct user_dbg_data {
	unsigned long avail_size;
	unsigned long write;
	unsigned long read;
};

struct ltt_trace_ops {
	/* First 32 bytes cache-hot cacheline */
	void (*wakeup_channel) (struct ust_channel *channel);
	int (*user_blocking) (struct ust_trace *trace,
				unsigned int index, size_t data_size,
				struct user_dbg_data *dbg);
	/* End of first 32 bytes cacheline */
	int (*create_dirs) (struct ust_trace *new_trace);
	void (*remove_dirs) (struct ust_trace *new_trace);
	int (*create_channel) (const char *trace_name,
				struct ust_trace *trace,
				const char *channel_name,
				struct ust_channel *channel,
				unsigned int subbuf_size,
				unsigned int n_subbufs, int overwrite);
	void (*finish_channel) (struct ust_channel *channel);
	void (*remove_channel) (struct ust_channel *channel);
	void (*user_errors) (struct ust_trace *trace,
				unsigned int index, size_t data_size,
				struct user_dbg_data *dbg, unsigned int cpu);
};

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

enum trace_mode { LTT_TRACE_NORMAL, LTT_TRACE_FLIGHT, LTT_TRACE_HYBRID };

#define CHANNEL_FLAG_ENABLE	(1U<<0)
#define CHANNEL_FLAG_OVERWRITE	(1U<<1)

/* Per-trace information - each trace/flight recorder represented by one */
struct ust_trace {
	/* First 32 bytes cache-hot cacheline */
	struct list_head list;
	struct ltt_trace_ops *ops;
	int active;
	/* Second 32 bytes cache-hot cacheline */
	struct ust_channel *channels;
	unsigned int nr_channels;
	u32 freq_scale;
	u64 start_freq;
	u64 start_tsc;
	unsigned long long start_monotonic;
	struct timeval		start_time;
	struct ltt_channel_setting *settings;
	struct {
		struct dentry			*trace_root;
	} dentry;
	struct kref kref; /* Each channel has a kref of the trace struct */
	struct ltt_transport *transport;
	struct kref ltt_transport_kref;
	char trace_name[NAME_MAX];
} ____cacheline_aligned;

/*
 * 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 ltt_subbuffer_header {
	uint64_t cycle_count_begin;	/* Cycle count at subbuffer start */
	uint64_t cycle_count_end;	/* Cycle count at subbuffer end */
	uint32_t magic_number;		/*
					 * Trace magic number.
					 * contains endianness information.
					 */
	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) */
	uint32_t lost_size;		/* Size unused at end of subbuffer */
	uint32_t buf_size;		/* Size of this subbuffer */
	uint32_t events_lost;		/*
					 * Events lost in this subbuffer since
					 * the beginning of the trace.
					 * (may overflow)
					 */
	uint32_t subbuf_corrupt;	/*
					 * Corrupted (lost) subbuffers since
					 * the begginig of the trace.
					 * (may overflow)
					 */
	uint8_t header_end[0];		/* End of header */
};

/**
 * ltt_subbuffer_header_size - called on buffer-switch to a new sub-buffer
 *
 * Return header size without padding after the structure. Don't use packed
 * structure because gcc generates inefficient code on some architectures
 * (powerpc, mips..)
 */
static __inline__ size_t ltt_subbuffer_header_size(void)
{
	return offsetof(struct ltt_subbuffer_header, header_end);
}

extern size_t ltt_write_event_header_slow(struct ust_trace *trace,
               struct ust_channel *channel,
               struct ust_buffer *buf, long buf_offset,
               u16 eID, u32 event_size,
               u64 tsc, unsigned int rflags);


/*
 * ltt_write_event_header
 *
 * Writes the event header to the offset (already aligned on 32-bits).
 *
 * @trace : trace to write to.
 * @channel : pointer to the channel structure..
 * @buf : buffer to write to.
 * @buf_offset : buffer offset to write to (aligned on 32 bits).
 * @eID : event ID
 * @event_size : size of the event, excluding the event header.
 * @tsc : time stamp counter.
 * @rflags : reservation flags.
 *
 * returns : offset where the event data must be written.
 */
static __inline__ size_t ltt_write_event_header(struct ust_trace *trace,
		struct ust_channel *channel,
		struct ust_buffer *buf, long buf_offset,
		u16 eID, u32 event_size,
		u64 tsc, unsigned int rflags)
{
	struct ltt_event_header header;

	if (unlikely(rflags))
		goto slow_path;

	header.id_time = eID << LTT_TSC_BITS;

	return buf_offset;

slow_path:
	return ltt_write_event_header_slow(trace, channel, buf, buf_offset,
				eID, event_size, tsc, rflags);
}

/*
 * Control channels :
 * control/metadata
 * control/interrupts
 * control/...
 *
 * cpu channel :
 * cpu
 */

#define LTT_METADATA_CHANNEL		"metadata_state"
#define LTT_UST_CHANNEL			"ust"

#define LTT_FLIGHT_PREFIX	"flight-"

/* Tracer properties */
//#define LTT_DEFAULT_SUBBUF_SIZE_LOW	134217728
#define LTT_DEFAULT_SUBBUF_SIZE_LOW	65536
//#define LTT_DEFAULT_SUBBUF_SIZE_LOW	4096
#define LTT_DEFAULT_N_SUBBUFS_LOW	2
//#define LTT_DEFAULT_SUBBUF_SIZE_MED	134217728
#define LTT_DEFAULT_SUBBUF_SIZE_MED	262144
//#define LTT_DEFAULT_SUBBUF_SIZE_MED	4096
#define LTT_DEFAULT_N_SUBBUFS_MED	2
//#define LTT_DEFAULT_SUBBUF_SIZE_HIGH	134217728
#define LTT_DEFAULT_SUBBUF_SIZE_HIGH	1048576
//#define LTT_DEFAULT_SUBBUF_SIZE_HIGH	4096
#define LTT_DEFAULT_N_SUBBUFS_HIGH	2
#define LTT_TRACER_MAGIC_NUMBER		0x00D6B7ED
#define LTT_TRACER_VERSION_MAJOR	2
#define LTT_TRACER_VERSION_MINOR	4

/**
 * ust_write_trace_header - Write trace header
 * @trace: Trace information
 * @header: Memory address where the information must be written to
 */
static __inline__ void ltt_write_trace_header(struct ust_trace *trace,
               struct ltt_subbuffer_header *header)
{
	header->magic_number = LTT_TRACER_MAGIC_NUMBER;
	header->major_version = LTT_TRACER_VERSION_MAJOR;
	header->minor_version = LTT_TRACER_VERSION_MINOR;
	header->arch_size = sizeof(void *);
	header->alignment = ltt_get_alignment();
	header->start_time_sec = trace->start_time.tv_sec;
	header->start_time_usec = trace->start_time.tv_usec;
	header->start_freq = trace->start_freq;
	header->freq_scale = trace->freq_scale;
}


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

/* Exported control function */

union ltt_control_args {
	struct {
		enum trace_mode mode;
		unsigned int subbuf_size_low;
		unsigned int n_subbufs_low;
		unsigned int subbuf_size_med;
		unsigned int n_subbufs_med;
		unsigned int subbuf_size_high;
		unsigned int n_subbufs_high;
	} new_trace;
};

extern int _ltt_trace_setup(const char *trace_name);
extern int ltt_trace_setup(const char *trace_name);
extern struct ust_trace *_ltt_trace_find_setup(const char *trace_name);
extern int ltt_trace_set_type(const char *trace_name, const char *trace_type);
extern int ltt_trace_set_channel_subbufsize(const char *trace_name,
		const char *channel_name, unsigned int size);
extern int ltt_trace_set_channel_subbufcount(const char *trace_name,
		const char *channel_name, unsigned int cnt);
extern int ltt_trace_set_channel_enable(const char *trace_name,
		const char *channel_name, unsigned int enable);
extern int ltt_trace_set_channel_overwrite(const char *trace_name,
		const char *channel_name, unsigned int overwrite);
extern int ltt_trace_alloc(const char *trace_name);
extern int ltt_trace_destroy(const char *trace_name);
extern int ltt_trace_start(const char *trace_name);
extern int ltt_trace_stop(const char *trace_name);

enum ltt_filter_control_msg {
	LTT_FILTER_DEFAULT_ACCEPT,
	LTT_FILTER_DEFAULT_REJECT
};

extern int ltt_filter_control(enum ltt_filter_control_msg msg,
		const char *trace_name);

extern struct dentry *get_filter_root(void);

extern void ltt_write_trace_header(struct ust_trace *trace,
		struct ltt_subbuffer_header *header);
extern void ltt_buffer_destroy(struct ust_channel *ltt_chan);

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

extern void ltt_core_unregister(void);

extern void ltt_release_trace(struct kref *kref);
extern void ltt_release_transport(struct kref *kref);

extern void ltt_dump_marker_state(struct ust_trace *trace);

extern void ltt_lock_traces(void);
extern void ltt_unlock_traces(void);

extern struct ust_trace *_ltt_trace_find(const char *trace_name);

#endif /* _LTT_TRACER_H */
Commit	Line	Data
	1	/*
	2	* Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
	3	* Copyright (C) 2009 Pierre-Marc Fournier
	4	*
	5	* This contains the definitions for the Linux Trace Toolkit tracer.
	6	*
	7	* Ported to userspace by Pierre-Marc Fournier.
	8	*
	9	* This library is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU Lesser General Public
	11	* License as published by the Free Software Foundation; either
	12	* version 2.1 of the License, or (at your option) any later version.
	13	*
	14	* This library is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* Lesser General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU Lesser General Public
	20	* License along with this library; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	22	*/
	23
	24	#ifndef _LTT_TRACER_H
	25	#define _LTT_TRACER_H
	26
	27	#include <sys/types.h>
	28	#include <stdarg.h>
	29	#include <ust/kernelcompat.h>
	30	#include "channels.h"
	31	#include "tracercore.h"
	32	#include "tracerconst.h"
	33	#include <ust/marker.h>
	34	#include <ust/probe.h>
	35
	36	/* Number of bytes to log with a read/write event */
	37	#define LTT_LOG_RW_SIZE 32L
	38
	39	/* Interval (in jiffies) at which the LTT per-CPU timer fires */
	40	#define LTT_PERCPU_TIMER_INTERVAL 1
	41
	42	#ifndef LTT_ARCH_TYPE
	43	#define LTT_ARCH_TYPE LTT_ARCH_TYPE_UNDEFINED
	44	#endif
	45
	46	#ifndef LTT_ARCH_VARIANT
	47	#define LTT_ARCH_VARIANT LTT_ARCH_VARIANT_NONE
	48	#endif
	49
	50	struct ltt_active_marker;
	51
	52	/* Maximum number of callbacks per marker */
	53	#define LTT_NR_CALLBACKS 10
	54
	55	struct ltt_serialize_closure;
	56	struct ltt_probe_private_data;
	57
	58	struct ltt_serialize_closure {
	59	ltt_serialize_cb *callbacks;
	60	long cb_args[LTT_NR_CALLBACKS];
	61	unsigned int cb_idx;
	62	};
	63
	64	extern size_t ltt_serialize_data(struct ust_buffer *buf, size_t buf_offset,
	65	struct ltt_serialize_closure *closure,
	66	void *serialize_private,
	67	int largest_align, const char fmt, va_list *args);
	68
	69	struct ltt_probe_private_data {
	70	struct ust_trace trace; /
	71	* Target trace, for metadata
	72	* or statedump.
	73	*/
	74	ltt_serialize_cb serializer; /*
	75	* Serialization function override.
	76	*/
	77	void serialize_private; /
	78	* Private data for serialization
	79	* functions.
	80	*/
	81	};
	82
	83	enum ltt_channels {
	84	LTT_CHANNEL_METADATA,
	85	LTT_CHANNEL_UST,
	86	};
	87
	88	struct ltt_active_marker {
	89	struct list_head node; /* active markers list */
	90	const char *channel;
	91	const char *name;
	92	const char *format;
	93	struct ltt_available_probe *probe;
	94	};
	95
	96	struct marker; //ust//
	97	extern void ltt_vtrace(const struct marker mdata, void probe_data,
	98	struct registers regs, void call_data, const char fmt, va_list args);
	99	extern void ltt_trace(const struct marker mdata, void probe_data,
	100	struct registers regs, void call_data, const char *fmt, ...);
	101
	102	/*
	103	* Unique ID assigned to each registered probe.
	104	*/
	105	enum marker_id {
	106	MARKER_ID_SET_MARKER_ID = 0, /* Static IDs available (range 0-7) */
	107	MARKER_ID_SET_MARKER_FORMAT,
	108	MARKER_ID_COMPACT, /* Compact IDs (range: 8-127) */
	109	MARKER_ID_DYNAMIC, /* Dynamic IDs (range: 128-65535) */
	110	};
	111
	112	/* static ids 0-1 reserved for internal use. */
	113	#define MARKER_CORE_IDS 2
	114	static __inline__ enum marker_id marker_id_type(uint16_t id)
	115	{
	116	if (id < MARKER_CORE_IDS)
	117	return (enum marker_id)id;
	118	else
	119	return MARKER_ID_DYNAMIC;
	120	}
	121
	122	struct user_dbg_data {
	123	unsigned long avail_size;
	124	unsigned long write;
	125	unsigned long read;
	126	};
	127
	128	struct ltt_trace_ops {
	129	/* First 32 bytes cache-hot cacheline */
	130	void (wakeup_channel) (struct ust_channel channel);
	131	int (user_blocking) (struct ust_trace trace,
	132	unsigned int index, size_t data_size,
	133	struct user_dbg_data *dbg);
	134	/* End of first 32 bytes cacheline */
	135	int (create_dirs) (struct ust_trace new_trace);
	136	void (remove_dirs) (struct ust_trace new_trace);
	137	int (create_channel) (const char trace_name,
	138	struct ust_trace *trace,
	139	const char *channel_name,
	140	struct ust_channel *channel,
	141	unsigned int subbuf_size,
	142	unsigned int n_subbufs, int overwrite);
	143	void (finish_channel) (struct ust_channel channel);
	144	void (remove_channel) (struct ust_channel channel);
	145	void (user_errors) (struct ust_trace trace,
	146	unsigned int index, size_t data_size,
	147	struct user_dbg_data *dbg, unsigned int cpu);
	148	};
	149
	150	struct ltt_transport {
	151	char *name;
	152	struct module *owner;
	153	struct list_head node;
	154	struct ltt_trace_ops ops;
	155	};
	156
	157	enum trace_mode { LTT_TRACE_NORMAL, LTT_TRACE_FLIGHT, LTT_TRACE_HYBRID };
	158
	159	#define CHANNEL_FLAG_ENABLE (1U<<0)
	160	#define CHANNEL_FLAG_OVERWRITE (1U<<1)
	161
	162	/* Per-trace information - each trace/flight recorder represented by one */
	163	struct ust_trace {
	164	/* First 32 bytes cache-hot cacheline */
	165	struct list_head list;
	166	struct ltt_trace_ops *ops;
	167	int active;
	168	/* Second 32 bytes cache-hot cacheline */
	169	struct ust_channel *channels;
	170	unsigned int nr_channels;
	171	u32 freq_scale;
	172	u64 start_freq;
	173	u64 start_tsc;
	174	unsigned long long start_monotonic;
	175	struct timeval start_time;
	176	struct ltt_channel_setting *settings;
	177	struct {
	178	struct dentry *trace_root;
	179	} dentry;
	180	struct kref kref; /* Each channel has a kref of the trace struct */
	181	struct ltt_transport *transport;
	182	struct kref ltt_transport_kref;
	183	char trace_name[NAME_MAX];
	184	} ____cacheline_aligned;
	185
	186	/*
	187	* We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
	188	* specifically with CPU frequency scaling someday, so using an interpolation
	189	* between the start and end of buffer values is not flexible enough. Using an
	190	* immediate frequency value permits to calculate directly the times for parts
	191	* of a buffer that would be before a frequency change.
	192	*
	193	* Keep the natural field alignment for _each field_ within this structure if
	194	* you ever add/remove a field from this header. Packed attribute is not used
	195	* because gcc generates poor code on at least powerpc and mips. Don't ever
	196	* let gcc add padding between the structure elements.
	197	*/
	198	struct ltt_subbuffer_header {
	199	uint64_t cycle_count_begin; /* Cycle count at subbuffer start */
	200	uint64_t cycle_count_end; /* Cycle count at subbuffer end */
	201	uint32_t magic_number; /*
	202	* Trace magic number.
	203	* contains endianness information.
	204	*/
	205	uint8_t major_version;
	206	uint8_t minor_version;
	207	uint8_t arch_size; /* Architecture pointer size */
	208	uint8_t alignment; /* LTT data alignment */
	209	uint64_t start_time_sec; /* NTP-corrected start time */
	210	uint64_t start_time_usec;
	211	uint64_t start_freq; /*
	212	* Frequency at trace start,
	213	* used all along the trace.
	214	*/
	215	uint32_t freq_scale; /* Frequency scaling (divisor) */
	216	uint32_t lost_size; /* Size unused at end of subbuffer */
	217	uint32_t buf_size; /* Size of this subbuffer */
	218	uint32_t events_lost; /*
	219	* Events lost in this subbuffer since
	220	* the beginning of the trace.
	221	* (may overflow)
	222	*/
	223	uint32_t subbuf_corrupt; /*
	224	* Corrupted (lost) subbuffers since
	225	* the begginig of the trace.
	226	* (may overflow)
	227	*/
	228	uint8_t header_end[0]; /* End of header */
	229	};
	230
	231	/**
	232	* ltt_subbuffer_header_size - called on buffer-switch to a new sub-buffer
	233	*
	234	* Return header size without padding after the structure. Don't use packed
	235	* structure because gcc generates inefficient code on some architectures
	236	* (powerpc, mips..)
	237	*/
	238	static __inline__ size_t ltt_subbuffer_header_size(void)
	239	{
	240	return offsetof(struct ltt_subbuffer_header, header_end);
	241	}
	242
	243	extern size_t ltt_write_event_header_slow(struct ust_trace *trace,
	244	struct ust_channel *channel,
	245	struct ust_buffer *buf, long buf_offset,
	246	u16 eID, u32 event_size,
	247	u64 tsc, unsigned int rflags);
	248
	249
	250	/*
	251	* ltt_write_event_header
	252	*
	253	* Writes the event header to the offset (already aligned on 32-bits).
	254	*
	255	* @trace : trace to write to.
	256	* @channel : pointer to the channel structure..
	257	* @buf : buffer to write to.
	258	* @buf_offset : buffer offset to write to (aligned on 32 bits).
	259	* @eID : event ID
	260	* @event_size : size of the event, excluding the event header.
	261	* @tsc : time stamp counter.
	262	* @rflags : reservation flags.
	263	*
	264	* returns : offset where the event data must be written.
	265	*/
	266	static __inline__ size_t ltt_write_event_header(struct ust_trace *trace,
	267	struct ust_channel *channel,
	268	struct ust_buffer *buf, long buf_offset,
	269	u16 eID, u32 event_size,
	270	u64 tsc, unsigned int rflags)
	271	{
	272	struct ltt_event_header header;
	273
	274	if (unlikely(rflags))
	275	goto slow_path;
	276
	277	header.id_time = eID << LTT_TSC_BITS;
	278
	279	return buf_offset;
	280
	281	slow_path:
	282	return ltt_write_event_header_slow(trace, channel, buf, buf_offset,
	283	eID, event_size, tsc, rflags);
	284	}
	285
	286	/*
	287	* Control channels :
	288	* control/metadata
	289	* control/interrupts
	290	* control/...
	291	*
	292	* cpu channel :
	293	* cpu
	294	*/
	295
	296	#define LTT_METADATA_CHANNEL "metadata_state"
	297	#define LTT_UST_CHANNEL "ust"
	298
	299	#define LTT_FLIGHT_PREFIX "flight-"
	300
	301	/* Tracer properties */
	302	//#define LTT_DEFAULT_SUBBUF_SIZE_LOW 134217728
	303	#define LTT_DEFAULT_SUBBUF_SIZE_LOW 65536
	304	//#define LTT_DEFAULT_SUBBUF_SIZE_LOW 4096
	305	#define LTT_DEFAULT_N_SUBBUFS_LOW 2
	306	//#define LTT_DEFAULT_SUBBUF_SIZE_MED 134217728
	307	#define LTT_DEFAULT_SUBBUF_SIZE_MED 262144
	308	//#define LTT_DEFAULT_SUBBUF_SIZE_MED 4096
	309	#define LTT_DEFAULT_N_SUBBUFS_MED 2
	310	//#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 134217728
	311	#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 1048576
	312	//#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 4096
	313	#define LTT_DEFAULT_N_SUBBUFS_HIGH 2
	314	#define LTT_TRACER_MAGIC_NUMBER 0x00D6B7ED
	315	#define LTT_TRACER_VERSION_MAJOR 2
	316	#define LTT_TRACER_VERSION_MINOR 4
	317
	318	/**
	319	* ust_write_trace_header - Write trace header
	320	* @trace: Trace information
	321	* @header: Memory address where the information must be written to
	322	*/
	323	static __inline__ void ltt_write_trace_header(struct ust_trace *trace,
	324	struct ltt_subbuffer_header *header)
	325	{
	326	header->magic_number = LTT_TRACER_MAGIC_NUMBER;
	327	header->major_version = LTT_TRACER_VERSION_MAJOR;
	328	header->minor_version = LTT_TRACER_VERSION_MINOR;
	329	header->arch_size = sizeof(void *);
	330	header->alignment = ltt_get_alignment();
	331	header->start_time_sec = trace->start_time.tv_sec;
	332	header->start_time_usec = trace->start_time.tv_usec;
	333	header->start_freq = trace->start_freq;
	334	header->freq_scale = trace->freq_scale;
	335	}
	336
	337
	338	/*
	339	* Size reserved for high priority events (interrupts, NMI, BH) at the end of a
	340	* nearly full buffer. User space won't use this last amount of space when in
	341	* blocking mode. This space also includes the event header that would be
	342	* written by this user space event.
	343	*/
	344	#define LTT_RESERVE_CRITICAL 4096
	345
	346	/* Register and unregister function pointers */
	347
	348	enum ltt_module_function {
	349	LTT_FUNCTION_RUN_FILTER,
	350	LTT_FUNCTION_FILTER_CONTROL,
	351	LTT_FUNCTION_STATEDUMP
	352	};
	353
	354	extern void ltt_transport_register(struct ltt_transport *transport);
	355	extern void ltt_transport_unregister(struct ltt_transport *transport);
	356
	357	/* Exported control function */
	358
	359	union ltt_control_args {
	360	struct {
	361	enum trace_mode mode;
	362	unsigned int subbuf_size_low;
	363	unsigned int n_subbufs_low;
	364	unsigned int subbuf_size_med;
	365	unsigned int n_subbufs_med;
	366	unsigned int subbuf_size_high;
	367	unsigned int n_subbufs_high;
	368	} new_trace;
	369	};
	370
	371	extern int _ltt_trace_setup(const char *trace_name);
	372	extern int ltt_trace_setup(const char *trace_name);
	373	extern struct ust_trace _ltt_trace_find_setup(const char trace_name);
	374	extern int ltt_trace_set_type(const char trace_name, const char trace_type);
	375	extern int ltt_trace_set_channel_subbufsize(const char *trace_name,
	376	const char *channel_name, unsigned int size);
	377	extern int ltt_trace_set_channel_subbufcount(const char *trace_name,
	378	const char *channel_name, unsigned int cnt);
	379	extern int ltt_trace_set_channel_enable(const char *trace_name,
	380	const char *channel_name, unsigned int enable);
	381	extern int ltt_trace_set_channel_overwrite(const char *trace_name,
	382	const char *channel_name, unsigned int overwrite);
	383	extern int ltt_trace_alloc(const char *trace_name);
	384	extern int ltt_trace_destroy(const char *trace_name);
	385	extern int ltt_trace_start(const char *trace_name);
	386	extern int ltt_trace_stop(const char *trace_name);
	387
	388	enum ltt_filter_control_msg {
	389	LTT_FILTER_DEFAULT_ACCEPT,
	390	LTT_FILTER_DEFAULT_REJECT
	391	};
	392
	393	extern int ltt_filter_control(enum ltt_filter_control_msg msg,
	394	const char *trace_name);
	395
	396	extern struct dentry *get_filter_root(void);
	397
	398	extern void ltt_write_trace_header(struct ust_trace *trace,
	399	struct ltt_subbuffer_header *header);
	400	extern void ltt_buffer_destroy(struct ust_channel *ltt_chan);
	401
	402	extern void ltt_core_register(int (function)(u8, void ));
	403
	404	extern void ltt_core_unregister(void);
	405
	406	extern void ltt_release_trace(struct kref *kref);
	407	extern void ltt_release_transport(struct kref *kref);
	408
	409	extern void ltt_dump_marker_state(struct ust_trace *trace);
	410
	411	extern void ltt_lock_traces(void);
	412	extern void ltt_unlock_traces(void);
	413
	414	extern struct ust_trace _ltt_trace_find(const char trace_name);
	415
	416	#endif /* _LTT_TRACER_H */