[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/marker.h>
#include <ust/marker-internal.h>
#include <ust/probe.h>
#include <ust/core.h>
#include "channels.h"
#include "tracercore.h"
#include "tracerconst.h"
#include "buffers.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_ust_marker;

/* Maximum number of callbacks per ust_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,
			unsigned int stack_pos_ctx, 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 chan_info_struct {
	const char *name;
	unsigned int def_subbufsize;
	unsigned int def_subbufcount;
};

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

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

/*
 * Unique ID assigned to each registered probe.
 */
enum ust_marker_id {
	UST_MARKER_ID_SET_MARKER_ID = 0,	/* Static IDs available (range 0-7) */
	UST_MARKER_ID_SET_MARKER_FORMAT,
	UST_MARKER_ID_COMPACT,		/* Compact IDs (range: 8-127)	    */
	UST_MARKER_ID_DYNAMIC,		/* Dynamic IDs (range: 128-65535)   */
};

/* static ids 0-1 reserved for internal use. */
#define UST_MARKER_CORE_IDS		2
static __inline__ enum ust_marker_id ust_marker_id_type(uint16_t id)
{
	if (id < UST_MARKER_CORE_IDS)
		return (enum ust_marker_id)id;
	else
		return UST_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 cds_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 cds_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 urcu_ref urcu_ref; /* Each channel has a urcu_ref of the trace struct */
	struct ltt_transport *transport;
	struct urcu_ref ltt_transport_urcu_ref;
	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 data_size;		/* Size of data in subbuffer */
	uint32_t sb_size;		/* Subbuffer size (including padding) */
	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_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_channel *chan,
		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;
	header.id_time |= (u32)tsc & LTT_TSC_MASK;
	ust_buffers_write(buf, buf_offset, &header, sizeof(header));
	buf_offset += sizeof(header);

	return buf_offset;

slow_path:
	return ltt_write_event_header_slow(chan, 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	6

/**
 * 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;
}

#ifndef UST_VALGRIND

static __inline__ int ust_get_cpu(void)
{
	int cpu;

	cpu = sched_getcpu();
	if (likely(cpu >= 0))
		return cpu;
	/*
	 * If getcpu(2) is not implemented in the Kernel use CPU 0 as fallback.
	 */
	return 0;
}

#else	/* #else #ifndef UST_VALGRIND */

static __inline__ int ust_get_cpu(void)
{
	/*
	 * Valgrind does not support the sched_getcpu() vsyscall.
	 * It causes it to detect a segfault in the program and stop it.
	 * So if we want to check libust with valgrind, we have to refrain
	 * from using this call. TODO: it would probably be better to return
	 * other values too, to better test it.
	 */
	return 0;
}

#endif	/* #else #ifndef UST_VALGRIND */

/*
 * 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, int drop);
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 urcu_ref *urcu_ref);
extern void ltt_release_transport(struct urcu_ref *urcu_ref);

extern void ltt_dump_ust_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
9dad1eb8 PMF	1	/*
9dad1eb8 PMF	2	* Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
e4621c7f	3	* Copyright (C) 2009 Pierre-Marc Fournier
9dad1eb8 PMF	4	*
9dad1eb8 PMF	5	* This contains the definitions for the Linux Trace Toolkit tracer.
e4621c7f PMF	6	*
	7	* Ported to userspace by Pierre-Marc Fournier.
	8	*
8fc2d8db PMF	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
9dad1eb8 PMF	22	*/
	23
	24	#ifndef _LTT_TRACER_H
	25	#define _LTT_TRACER_H
	26
b6bf28ec	27	#include <sys/types.h>
9dad1eb8	28	#include <stdarg.h>
518d7abb	29	#include <ust/marker.h>
535b0d0a	30	#include <ust/marker-internal.h>
518d7abb PMF	31	#include <ust/probe.h>
518d7abb PMF	32	#include <ust/core.h>
b6bf28ec	33	#include "channels.h"
bb07823d	34	#include "tracercore.h"
b73a4c47	35	#include "tracerconst.h"
8c36d1ee	36	#include "buffers.h"
9dad1eb8 PMF	37
	38	/* Number of bytes to log with a read/write event */
	39	#define LTT_LOG_RW_SIZE 32L
	40
	41	/* Interval (in jiffies) at which the LTT per-CPU timer fires */
	42	#define LTT_PERCPU_TIMER_INTERVAL 1
	43
	44	#ifndef LTT_ARCH_TYPE
	45	#define LTT_ARCH_TYPE LTT_ARCH_TYPE_UNDEFINED
	46	#endif
	47
	48	#ifndef LTT_ARCH_VARIANT
	49	#define LTT_ARCH_VARIANT LTT_ARCH_VARIANT_NONE
	50	#endif
	51
b521931e	52	struct ltt_active_ust_marker;
9dad1eb8	53
b521931e	54	/* Maximum number of callbacks per ust_marker */
9dad1eb8 PMF	55	#define LTT_NR_CALLBACKS 10
	56
	57	struct ltt_serialize_closure;
	58	struct ltt_probe_private_data;
	59
9dad1eb8 PMF	60	struct ltt_serialize_closure {
	61	ltt_serialize_cb *callbacks;
	62	long cb_args[LTT_NR_CALLBACKS];
	63	unsigned int cb_idx;
	64	};
	65
b5b073e2	66	extern size_t ltt_serialize_data(struct ust_buffer *buf, size_t buf_offset,
9dad1eb8 PMF	67	struct ltt_serialize_closure *closure,
9dad1eb8 PMF	68	void *serialize_private,
bb3132c8 MD	69	unsigned int stack_pos_ctx, int *largest_align,
bb3132c8 MD	70	const char fmt, va_list args);
9dad1eb8	71
9dad1eb8	72	struct ltt_probe_private_data {
b73a4c47	73	struct ust_trace trace; /
9dad1eb8 PMF	74	* Target trace, for metadata
	75	* or statedump.
	76	*/
	77	ltt_serialize_cb serializer; /*
	78	* Serialization function override.
	79	*/
	80	void serialize_private; /
	81	* Private data for serialization
	82	* functions.
	83	*/
	84	};
	85
	86	enum ltt_channels {
	87	LTT_CHANNEL_METADATA,
b6bf28ec	88	LTT_CHANNEL_UST,
9dad1eb8 PMF	89	};
9dad1eb8 PMF	90
223f2e7c AH	91	struct chan_info_struct {
	92	const char *name;
	93	unsigned int def_subbufsize;
	94	unsigned int def_subbufcount;
	95	};
	96
b521931e	97	struct ltt_active_ust_marker {
0222e121	98	struct cds_list_head node; /* active markers list */
9dad1eb8 PMF	99	const char *channel;
	100	const char *name;
	101	const char *format;
	102	struct ltt_available_probe *probe;
	103	};
	104
b521931e MD	105	struct ust_marker; //ust//
b521931e MD	106	extern void ltt_vtrace(const struct ust_marker mdata, void probe_data,
fe566790	107	void call_data, const char fmt, va_list *args);
b521931e	108	extern void ltt_trace(const struct ust_marker mdata, void probe_data,
fe566790	109	void call_data, const char fmt, ...);
9dad1eb8 PMF	110
	111	/*
	112	* Unique ID assigned to each registered probe.
	113	*/
b521931e MD	114	enum ust_marker_id {
	115	UST_MARKER_ID_SET_MARKER_ID = 0, /* Static IDs available (range 0-7) */
	116	UST_MARKER_ID_SET_MARKER_FORMAT,
	117	UST_MARKER_ID_COMPACT, /* Compact IDs (range: 8-127) */
	118	UST_MARKER_ID_DYNAMIC, /* Dynamic IDs (range: 128-65535) */
9dad1eb8 PMF	119	};
	120
	121	/* static ids 0-1 reserved for internal use. */
b521931e MD	122	#define UST_MARKER_CORE_IDS 2
b521931e MD	123	static __inline__ enum ust_marker_id ust_marker_id_type(uint16_t id)
9dad1eb8	124	{
b521931e MD	125	if (id < UST_MARKER_CORE_IDS)
b521931e MD	126	return (enum ust_marker_id)id;
9dad1eb8	127	else
b521931e	128	return UST_MARKER_ID_DYNAMIC;
9dad1eb8 PMF	129	}
9dad1eb8 PMF	130
9dad1eb8 PMF	131	struct user_dbg_data {
	132	unsigned long avail_size;
	133	unsigned long write;
	134	unsigned long read;
	135	};
	136
	137	struct ltt_trace_ops {
	138	/* First 32 bytes cache-hot cacheline */
b5b073e2	139	void (wakeup_channel) (struct ust_channel channel);
b73a4c47	140	int (user_blocking) (struct ust_trace trace,
bb07823d PMF	141	unsigned int index, size_t data_size,
bb07823d PMF	142	struct user_dbg_data *dbg);
b5b073e2	143	/* End of first 32 bytes cacheline */
b73a4c47 PMF	144	int (create_dirs) (struct ust_trace new_trace);
b73a4c47 PMF	145	void (remove_dirs) (struct ust_trace new_trace);
b5b073e2	146	int (create_channel) (const char trace_name,
b73a4c47	147	struct ust_trace *trace,
b5b073e2 PMF	148	const char *channel_name,
	149	struct ust_channel *channel,
	150	unsigned int subbuf_size,
	151	unsigned int n_subbufs, int overwrite);
	152	void (finish_channel) (struct ust_channel channel);
	153	void (remove_channel) (struct ust_channel channel);
b73a4c47	154	void (user_errors) (struct ust_trace trace,
b5b073e2	155	unsigned int index, size_t data_size,
204141ee	156	struct user_dbg_data *dbg, unsigned int cpu);
b73a4c47	157	};
9dad1eb8 PMF	158
	159	struct ltt_transport {
	160	char *name;
	161	struct module *owner;
0222e121	162	struct cds_list_head node;
9dad1eb8 PMF	163	struct ltt_trace_ops ops;
	164	};
	165
	166	enum trace_mode { LTT_TRACE_NORMAL, LTT_TRACE_FLIGHT, LTT_TRACE_HYBRID };
	167
	168	#define CHANNEL_FLAG_ENABLE (1U<<0)
	169	#define CHANNEL_FLAG_OVERWRITE (1U<<1)
	170
	171	/* Per-trace information - each trace/flight recorder represented by one */
b73a4c47	172	struct ust_trace {
9dad1eb8	173	/* First 32 bytes cache-hot cacheline */
0222e121	174	struct cds_list_head list;
9dad1eb8 PMF	175	struct ltt_trace_ops *ops;
	176	int active;
	177	/* Second 32 bytes cache-hot cacheline */
b5b073e2	178	struct ust_channel *channels;
9dad1eb8 PMF	179	unsigned int nr_channels;
	180	u32 freq_scale;
	181	u64 start_freq;
	182	u64 start_tsc;
	183	unsigned long long start_monotonic;
	184	struct timeval start_time;
	185	struct ltt_channel_setting *settings;
	186	struct {
	187	struct dentry *trace_root;
	188	} dentry;
205f7ca7	189	struct urcu_ref urcu_ref; /* Each channel has a urcu_ref of the trace struct */
9dad1eb8	190	struct ltt_transport *transport;
205f7ca7	191	struct urcu_ref ltt_transport_urcu_ref;
9dad1eb8 PMF	192	char trace_name[NAME_MAX];
	193	} ____cacheline_aligned;
	194
9dad1eb8 PMF	195	/*
	196	* We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
	197	* specifically with CPU frequency scaling someday, so using an interpolation
	198	* between the start and end of buffer values is not flexible enough. Using an
	199	* immediate frequency value permits to calculate directly the times for parts
	200	* of a buffer that would be before a frequency change.
	201	*
	202	* Keep the natural field alignment for _each field_ within this structure if
	203	* you ever add/remove a field from this header. Packed attribute is not used
	204	* because gcc generates poor code on at least powerpc and mips. Don't ever
	205	* let gcc add padding between the structure elements.
	206	*/
	207	struct ltt_subbuffer_header {
	208	uint64_t cycle_count_begin; /* Cycle count at subbuffer start */
	209	uint64_t cycle_count_end; /* Cycle count at subbuffer end */
	210	uint32_t magic_number; /*
	211	* Trace magic number.
	212	* contains endianness information.
	213	*/
	214	uint8_t major_version;
	215	uint8_t minor_version;
	216	uint8_t arch_size; /* Architecture pointer size */
	217	uint8_t alignment; /* LTT data alignment */
	218	uint64_t start_time_sec; /* NTP-corrected start time */
	219	uint64_t start_time_usec;
	220	uint64_t start_freq; /*
	221	* Frequency at trace start,
	222	* used all along the trace.
	223	*/
	224	uint32_t freq_scale; /* Frequency scaling (divisor) */
8c36d1ee PMF	225	uint32_t data_size; /* Size of data in subbuffer */
8c36d1ee PMF	226	uint32_t sb_size; /* Subbuffer size (including padding) */
9dad1eb8 PMF	227	uint32_t events_lost; /*
	228	* Events lost in this subbuffer since
	229	* the beginning of the trace.
	230	* (may overflow)
	231	*/
	232	uint32_t subbuf_corrupt; /*
	233	* Corrupted (lost) subbuffers since
	234	* the begginig of the trace.
	235	* (may overflow)
	236	*/
	237	uint8_t header_end[0]; /* End of header */
	238	};
	239
	240	/**
	241	* ltt_subbuffer_header_size - called on buffer-switch to a new sub-buffer
	242	*
	243	* Return header size without padding after the structure. Don't use packed
	244	* structure because gcc generates inefficient code on some architectures
	245	* (powerpc, mips..)
	246	*/
a2fd50ef	247	static __inline__ size_t ltt_subbuffer_header_size(void)
9dad1eb8 PMF	248	{
	249	return offsetof(struct ltt_subbuffer_header, header_end);
	250	}
	251
12e81b07	252	extern size_t ltt_write_event_header_slow(struct ust_channel *channel,
b73a4c47 PMF	253	struct ust_buffer *buf, long buf_offset,
	254	u16 eID, u32 event_size,
	255	u64 tsc, unsigned int rflags);
	256
9dad1eb8 PMF	257
	258	/*
	259	* ltt_write_event_header
	260	*
	261	* Writes the event header to the offset (already aligned on 32-bits).
	262	*
	263	* @trace : trace to write to.
	264	* @channel : pointer to the channel structure..
	265	* @buf : buffer to write to.
	266	* @buf_offset : buffer offset to write to (aligned on 32 bits).
	267	* @eID : event ID
	268	* @event_size : size of the event, excluding the event header.
	269	* @tsc : time stamp counter.
	270	* @rflags : reservation flags.
	271	*
	272	* returns : offset where the event data must be written.
	273	*/
12e81b07	274	static __inline__ size_t ltt_write_event_header(struct ust_channel *chan,
b5b073e2	275	struct ust_buffer *buf, long buf_offset,
b73a4c47	276	u16 eID, u32 event_size,
9dad1eb8 PMF	277	u64 tsc, unsigned int rflags)
	278	{
	279	struct ltt_event_header header;
9dad1eb8	280
b73a4c47 PMF	281	if (unlikely(rflags))
b73a4c47 PMF	282	goto slow_path;
9dad1eb8	283
b73a4c47	284	header.id_time = eID << LTT_TSC_BITS;
8c36d1ee PMF	285	header.id_time \|= (u32)tsc & LTT_TSC_MASK;
	286	ust_buffers_write(buf, buf_offset, &header, sizeof(header));
	287	buf_offset += sizeof(header);
9dad1eb8	288
b73a4c47	289	return buf_offset;
9dad1eb8	290
b73a4c47	291	slow_path:
12e81b07	292	return ltt_write_event_header_slow(chan, buf, buf_offset,
b73a4c47 PMF	293	eID, event_size, tsc, rflags);
b73a4c47 PMF	294	}
9dad1eb8 PMF	295
	296	/*
	297	* Control channels :
	298	* control/metadata
	299	* control/interrupts
	300	* control/...
	301	*
	302	* cpu channel :
	303	* cpu
	304	*/
9dad1eb8 PMF	305
9dad1eb8 PMF	306	#define LTT_METADATA_CHANNEL "metadata_state"
b6bf28ec	307	#define LTT_UST_CHANNEL "ust"
9dad1eb8 PMF	308
	309	#define LTT_FLIGHT_PREFIX "flight-"
	310
	311	/* Tracer properties */
32072f29 PMF	312	//#define LTT_DEFAULT_SUBBUF_SIZE_LOW 134217728
	313	#define LTT_DEFAULT_SUBBUF_SIZE_LOW 65536
	314	//#define LTT_DEFAULT_SUBBUF_SIZE_LOW 4096
9dad1eb8	315	#define LTT_DEFAULT_N_SUBBUFS_LOW 2
32072f29 PMF	316	//#define LTT_DEFAULT_SUBBUF_SIZE_MED 134217728
	317	#define LTT_DEFAULT_SUBBUF_SIZE_MED 262144
	318	//#define LTT_DEFAULT_SUBBUF_SIZE_MED 4096
9dad1eb8	319	#define LTT_DEFAULT_N_SUBBUFS_MED 2
32072f29 PMF	320	//#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 134217728
	321	#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 1048576
	322	//#define LTT_DEFAULT_SUBBUF_SIZE_HIGH 4096
9dad1eb8 PMF	323	#define LTT_DEFAULT_N_SUBBUFS_HIGH 2
	324	#define LTT_TRACER_MAGIC_NUMBER 0x00D6B7ED
	325	#define LTT_TRACER_VERSION_MAJOR 2
31607b38	326	#define LTT_TRACER_VERSION_MINOR 6
9dad1eb8	327
b73a4c47 PMF	328	/**
	329	* ust_write_trace_header - Write trace header
	330	* @trace: Trace information
	331	* @header: Memory address where the information must be written to
	332	*/
	333	static __inline__ void ltt_write_trace_header(struct ust_trace *trace,
	334	struct ltt_subbuffer_header *header)
	335	{
	336	header->magic_number = LTT_TRACER_MAGIC_NUMBER;
	337	header->major_version = LTT_TRACER_VERSION_MAJOR;
	338	header->minor_version = LTT_TRACER_VERSION_MINOR;
	339	header->arch_size = sizeof(void *);
	340	header->alignment = ltt_get_alignment();
	341	header->start_time_sec = trace->start_time.tv_sec;
	342	header->start_time_usec = trace->start_time.tv_usec;
	343	header->start_freq = trace->start_freq;
	344	header->freq_scale = trace->freq_scale;
	345	}
	346
8f09cb93 MD	347	#ifndef UST_VALGRIND
8f09cb93 MD	348
12e81b07 PMF	349	static __inline__ int ust_get_cpu(void)
12e81b07 PMF	350	{
8f09cb93 MD	351	int cpu;
	352
	353	cpu = sched_getcpu();
	354	if (likely(cpu >= 0))
	355	return cpu;
	356	/*
	357	* If getcpu(2) is not implemented in the Kernel use CPU 0 as fallback.
	358	*/
	359	return 0;
	360	}
	361
	362	#else /* #else #ifndef UST_VALGRIND */
	363
	364	static __inline__ int ust_get_cpu(void)
	365	{
	366	/*
	367	* Valgrind does not support the sched_getcpu() vsyscall.
12e81b07 PMF	368	* It causes it to detect a segfault in the program and stop it.
	369	* So if we want to check libust with valgrind, we have to refrain
	370	* from using this call. TODO: it would probably be better to return
	371	* other values too, to better test it.
	372	*/
	373	return 0;
12e81b07 PMF	374	}
12e81b07 PMF	375
8f09cb93	376	#endif /* #else #ifndef UST_VALGRIND */
b73a4c47	377
9dad1eb8 PMF	378	/*
	379	* Size reserved for high priority events (interrupts, NMI, BH) at the end of a
	380	* nearly full buffer. User space won't use this last amount of space when in
	381	* blocking mode. This space also includes the event header that would be
	382	* written by this user space event.
	383	*/
	384	#define LTT_RESERVE_CRITICAL 4096
	385
	386	/* Register and unregister function pointers */
	387
	388	enum ltt_module_function {
	389	LTT_FUNCTION_RUN_FILTER,
	390	LTT_FUNCTION_FILTER_CONTROL,
	391	LTT_FUNCTION_STATEDUMP
	392	};
	393
064842c6 PMF	394	extern void ltt_transport_register(struct ltt_transport *transport);
064842c6 PMF	395	extern void ltt_transport_unregister(struct ltt_transport *transport);
9dad1eb8 PMF	396
	397	/* Exported control function */
	398
9dad1eb8 PMF	399	union ltt_control_args {
	400	struct {
	401	enum trace_mode mode;
	402	unsigned int subbuf_size_low;
	403	unsigned int n_subbufs_low;
	404	unsigned int subbuf_size_med;
	405	unsigned int n_subbufs_med;
	406	unsigned int subbuf_size_high;
	407	unsigned int n_subbufs_high;
	408	} new_trace;
	409	};
	410
064842c6 PMF	411	extern int _ltt_trace_setup(const char *trace_name);
064842c6 PMF	412	extern int ltt_trace_setup(const char *trace_name);
b73a4c47	413	extern struct ust_trace _ltt_trace_find_setup(const char trace_name);
064842c6 PMF	414	extern int ltt_trace_set_type(const char trace_name, const char trace_type);
064842c6 PMF	415	extern int ltt_trace_set_channel_subbufsize(const char *trace_name,
9dad1eb8	416	const char *channel_name, unsigned int size);
064842c6	417	extern int ltt_trace_set_channel_subbufcount(const char *trace_name,
9dad1eb8	418	const char *channel_name, unsigned int cnt);
064842c6	419	extern int ltt_trace_set_channel_enable(const char *trace_name,
9dad1eb8	420	const char *channel_name, unsigned int enable);
064842c6	421	extern int ltt_trace_set_channel_overwrite(const char *trace_name,
9dad1eb8	422	const char *channel_name, unsigned int overwrite);
064842c6	423	extern int ltt_trace_alloc(const char *trace_name);
31d392f1	424	extern int ltt_trace_destroy(const char *trace_name, int drop);
064842c6 PMF	425	extern int ltt_trace_start(const char *trace_name);
064842c6 PMF	426	extern int ltt_trace_stop(const char *trace_name);
9dad1eb8	427
9dad1eb8 PMF	428	enum ltt_filter_control_msg {
	429	LTT_FILTER_DEFAULT_ACCEPT,
	430	LTT_FILTER_DEFAULT_REJECT
	431	};
	432
	433	extern int ltt_filter_control(enum ltt_filter_control_msg msg,
	434	const char *trace_name);
	435
	436	extern struct dentry *get_filter_root(void);
	437
b73a4c47	438	extern void ltt_write_trace_header(struct ust_trace *trace,
9dad1eb8	439	struct ltt_subbuffer_header *header);
b5b073e2	440	extern void ltt_buffer_destroy(struct ust_channel *ltt_chan);
9dad1eb8	441
064842c6	442	extern void ltt_core_register(int (function)(u8, void ));
9dad1eb8	443
064842c6	444	extern void ltt_core_unregister(void);
9dad1eb8	445
205f7ca7 DG	446	extern void ltt_release_trace(struct urcu_ref *urcu_ref);
205f7ca7 DG	447	extern void ltt_release_transport(struct urcu_ref *urcu_ref);
9dad1eb8	448
b521931e	449	extern void ltt_dump_ust_marker_state(struct ust_trace *trace);
9dad1eb8	450
064842c6 PMF	451	extern void ltt_lock_traces(void);
064842c6 PMF	452	extern void ltt_unlock_traces(void);
9dad1eb8	453
b73a4c47	454	extern struct ust_trace _ltt_trace_find(const char trace_name);
d0b5f2b9	455
9dad1eb8	456	#endif /* _LTT_TRACER_H */