[ust.git] / include / ust / tracepoint.h

#ifndef _UST_TRACEPOINT_H
#define _UST_TRACEPOINT_H

/*
 * Copyright (C) 2008 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
 * Copyright (C) 2009 Pierre-Marc Fournier
 * Copyright (C) 2009 Steven Rostedt <rostedt@goodmis.org>
 *
 * 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
 *
 * Heavily inspired from the Linux Kernel Markers.
 *
 * Ported to userspace by Pierre-Marc Fournier.
 */

#define _LGPL_SOURCE
#include <urcu-bp.h>
#include <ust/immediate.h>
#include <ust/core.h>

struct module;
struct tracepoint;

struct probe {
	void *func;
	void *data;
};

struct tracepoint {
	const char *name;		/* Tracepoint name */
	DEFINE_IMV(char, state);	/* State. */
	struct probe *probes;
};

#define PARAMS(args...) args

#define TP_PROTO(args...)	args
#define TP_ARGS(args...)	args

/*
 * Tracepoints should be added to the instrumented code using the
 * "tracepoint()" macro.
 */
#define tracepoint(name, args...)	__trace_##name(args)

#define register_tracepoint(name, probe, data)			\
		__register_trace_##name(probe, data)

#define unregister_tracepoint(name, probe, data)		\
		__unregister_trace_##name(probe, data)

#define CONFIG_TRACEPOINTS
#ifdef CONFIG_TRACEPOINTS

/*
 * it_func[0] is never NULL because there is at least one element in the array
 * when the array itself is non NULL.
 */
#define __DO_TRACE(tp, proto, args)					\
	do {								\
		struct probe *it_probe_ptr;				\
		void *it_func;						\
		void *__data;						\
									\
		rcu_read_lock();					\
		it_probe_ptr = rcu_dereference((tp)->probes);		\
		if (it_probe_ptr) {					\
			do {						\
				it_func	= (it_probe_ptr)->func;		\
				__data = (it_probe_ptr)->data;		\
				((void(*)(proto))(it_func))(args);	\
			} while ((++it_probe_ptr)->func);		\
		}							\
		rcu_read_unlock();					\
	} while (0)

#define __CHECK_TRACE(name, generic, proto, args)			\
	do {								\
		if (!generic) {						\
			if (unlikely(imv_read(__tracepoint_##name.state))) \
				__DO_TRACE(&__tracepoint_##name,	\
					TP_PROTO(proto), TP_ARGS(args));	\
		} else {						\
			if (unlikely(_imv_read(__tracepoint_##name.state))) \
				__DO_TRACE(&__tracepoint_##name,	\
					TP_PROTO(proto), TP_ARGS(args));	\
		}							\
	} while (0)

/*
 * Make sure the alignment of the structure in the __tracepoints section will
 * not add unwanted padding between the beginning of the section and the
 * structure. Force alignment to the same alignment as the section start.
 *
 * The "generic" argument, passed to the declared __trace_##name inline
 * function controls which tracepoint enabling mechanism must be used.
 * If generic is true, a variable read is used.
 * If generic is false, immediate values are used.
 */
#define __DECLARE_TRACE(name, proto, args, data_proto, data_args)	\
	extern struct tracepoint __tracepoint_##name;			\
	static inline void __trace_##name(proto)			\
	{								\
		__CHECK_TRACE(name, 0, TP_PROTO(data_proto),		\
			      TP_ARGS(data_args));			\
	}								\
	static inline void _trace_##name(proto)				\
	{								\
		__CHECK_TRACE(name, 1, TP_PROTO(data_proto),		\
			      TP_ARGS(data_args));			\
	}								\
	static inline int						\
	__register_trace_##name(void (*probe)(data_proto), void *data)	\
	{								\
		return tracepoint_probe_register(#name, (void *)probe,	\
						 data);			\
									\
	}								\
	static inline int						\
	__unregister_trace_##name(void (*probe)(data_proto), void *data)\
	{								\
		return tracepoint_probe_unregister(#name, (void *)probe, \
						   data);		\
	}

#define DEFINE_TRACE_FN(name, reg, unreg)				\
	static const char __tpstrtab_##name[]				\
	__attribute__((section("__tracepoints_strings"))) = #name;	\
	struct tracepoint __tracepoint_##name				\
	__attribute__((section("__tracepoints"))) =			\
		{ __tpstrtab_##name, 0, NULL };				\
	static struct tracepoint * const __tracepoint_ptr_##name	\
	__attribute__((used, section("__tracepoints_ptrs"))) =		\
		&__tracepoint_##name;

#define DEFINE_TRACE(name)						\
	DEFINE_TRACE_FN(name, NULL, NULL)

extern void tracepoint_update_probe_range(struct tracepoint * const *begin,
	struct tracepoint * const *end);

#else /* !CONFIG_TRACEPOINTS */
#define __DECLARE_TRACE(name, proto, args)				\
	static inline void trace_##name(proto)				\
	{ }								\
	static inline void _trace_##name(proto)				\
	{ }								\
	static inline int __register_trace_##name(void (*probe)(proto), void *data)	\
	{								\
		return -ENOSYS;						\
	}								\
	static inline int __unregister_trace_##name(void (*probe)(proto), void *data)	\
	{								\
		return -ENOSYS;						\
	}

#define DEFINE_TRACE(name)
#define EXPORT_TRACEPOINT_SYMBOL_GPL(name)
#define EXPORT_TRACEPOINT_SYMBOL(name)

static inline void tracepoint_update_probe_range(struct tracepoint *begin,
	struct tracepoint *end)
{ }
#endif /* CONFIG_TRACEPOINTS */

/*
 * The need for the DECLARE_TRACE_NOARGS() is to handle the prototype
 * (void). "void" is a special value in a function prototype and can
 * not be combined with other arguments. Since the DECLARE_TRACE()
 * macro adds a data element at the beginning of the prototype,
 * we need a way to differentiate "(void *data, proto)" from
 * "(void *data, void)". The second prototype is invalid.
 *
 * DECLARE_TRACE_NOARGS() passes "void" as the tracepoint prototype
 * and "void *__data" as the callback prototype.
 *
 * DECLARE_TRACE() passes "proto" as the tracepoint protoype and
 * "void *__data, proto" as the callback prototype.
 */
#define DECLARE_TRACE_NOARGS(name)					\
		__DECLARE_TRACE(name, void, , void *__data, __data)

#define DECLARE_TRACE(name, proto, args)				\
		__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args),	\
				PARAMS(void *__data, proto),		\
				PARAMS(__data, args))

/*
 * Connect a probe to a tracepoint.
 * Internal API, should not be used directly.
 */
extern int tracepoint_probe_register(const char *name, void *probe, void *data);

/*
 * Disconnect a probe from a tracepoint.
 * Internal API, should not be used directly.
 */
extern int tracepoint_probe_unregister(const char *name, void *probe, void *data);

extern int tracepoint_probe_register_noupdate(const char *name, void *probe,
					      void *data);
extern int tracepoint_probe_unregister_noupdate(const char *name, void *probe,
						void *data);
extern void tracepoint_probe_update_all(void);

struct tracepoint_iter {
//ust//	struct module *module;
	struct tracepoint_lib *lib;
	struct tracepoint * const *tracepoint;
};

extern void tracepoint_iter_start(struct tracepoint_iter *iter);
extern void tracepoint_iter_next(struct tracepoint_iter *iter);
extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
	struct tracepoint * const *begin, struct tracepoint * const *end);

/*
 * tracepoint_synchronize_unregister must be called between the last tracepoint
 * probe unregistration and the end of module exit to make sure there is no
 * caller executing a probe when it is freed.
 */
static inline void tracepoint_synchronize_unregister(void)
{
//ust//	synchronize_sched();
}

struct tracepoint_lib {
	struct tracepoint * const *tracepoints_start;
	int tracepoints_count;
	struct cds_list_head list;
};

extern int tracepoint_register_lib(struct tracepoint * const *tracepoints_start,
				   int tracepoints_count);
extern int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start);

#define TRACEPOINT_LIB							\
	extern struct tracepoint * const __start___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \
	extern struct tracepoint * const __stop___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \
	static struct tracepoint * const __tracepoint_ptr_dummy		\
	__attribute__((used, section("__tracepoints_ptrs"))) = NULL;	\
	static void __attribute__((constructor)) __tracepoints__init(void)	\
	{									\
		tracepoint_register_lib(__start___tracepoints_ptrs,			\
					__stop___tracepoints_ptrs -			\
					__start___tracepoints_ptrs);			\
	}									\
										\
	static void __attribute__((destructor)) __tracepoints__destroy(void)	\
	{									\
		tracepoint_unregister_lib(__start___tracepoints_ptrs);		\
	}


#ifndef TRACE_EVENT
/*
 * For use with the TRACE_EVENT macro:
 *
 * We define a tracepoint, its arguments, its printf format
 * and its 'fast binary record' layout.
 *
 * Firstly, name your tracepoint via TRACE_EVENT(name : the
 * 'subsystem_event' notation is fine.
 *
 * Think about this whole construct as the
 * 'trace_sched_switch() function' from now on.
 *
 *
 *  TRACE_EVENT(sched_switch,
 *
 *	*
 *	* A function has a regular function arguments
 *	* prototype, declare it via TP_PROTO():
 *	*
 *
 *	TP_PROTO(struct rq *rq, struct task_struct *prev,
 *		 struct task_struct *next),
 *
 *	*
 *	* Define the call signature of the 'function'.
 *	* (Design sidenote: we use this instead of a
 *	*  TP_PROTO1/TP_PROTO2/TP_PROTO3 ugliness.)
 *	*
 *
 *	TP_ARGS(rq, prev, next),
 *
 *	*
 *	* Fast binary tracing: define the trace record via
 *	* TP_STRUCT__entry(). You can think about it like a
 *	* regular C structure local variable definition.
 *	*
 *	* This is how the trace record is structured and will
 *	* be saved into the ring buffer. These are the fields
 *	* that will be exposed to readers.
 *	*
 *	* The declared 'local variable' is called '__entry'
 *	*
 *	* __field(pid_t, prev_prid) is equivalent to a standard declariton:
 *	*
 *	*	pid_t	prev_pid;
 *	*
 *	* __array(char, prev_comm, TASK_COMM_LEN) is equivalent to:
 *	*
 *	*	char	prev_comm[TASK_COMM_LEN];
 *	*
 *
 *	TP_STRUCT__entry(
 *		__array(	char,	prev_comm,	TASK_COMM_LEN	)
 *		__field(	pid_t,	prev_pid			)
 *		__field(	int,	prev_prio			)
 *		__array(	char,	next_comm,	TASK_COMM_LEN	)
 *		__field(	pid_t,	next_pid			)
 *		__field(	int,	next_prio			)
 *	),
 *
 *	*
 *	* Assign the entry into the trace record, by embedding
 *	* a full C statement block into TP_fast_assign(). You
 *	* can refer to the trace record as '__entry' -
 *	* otherwise you can put arbitrary C code in here.
 *	*
 *	* Note: this C code will execute every time a trace event
 *	* happens, on an active tracepoint.
 *	*
 *
 *	TP_fast_assign(
 *		memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN);
 *		__entry->prev_pid	= prev->pid;
 *		__entry->prev_prio	= prev->prio;
 *		memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN);
 *		__entry->next_pid	= next->pid;
 *		__entry->next_prio	= next->prio;
 *	)
 *
 *	*
 *	* Formatted output of a trace record via TP_printf().
 *	* This is how the tracepoint will appear under debugging
 *	* of tracepoints.
 *	*
 *	* (raw-binary tracing wont actually perform this step.)
 *	*
 *
 *	TP_printf("task %s:%d [%d] ==> %s:%d [%d]",
 *		__entry->prev_comm, __entry->prev_pid, __entry->prev_prio,
 *		__entry->next_comm, __entry->next_pid, __entry->next_prio),
 *
 * );
 *
 * This macro construct is thus used for the regular printf format
 * tracing setup.
 *
 * A set of (un)registration functions can be passed to the variant
 * TRACE_EVENT_FN to perform any (un)registration work.
 */

struct trace_event {
	const char *name;
	int (*regfunc)(void *data);
	int (*unregfunc)(void *data);
};

struct trace_event_lib {
	struct trace_event * const *trace_events_start;
	int trace_events_count;
	struct cds_list_head list;
};

struct trace_event_iter {
	struct trace_event_lib *lib;
	struct trace_event * const *trace_event;
};

extern void lock_trace_events(void);
extern void unlock_trace_events(void);

extern void trace_event_iter_start(struct trace_event_iter *iter);
extern void trace_event_iter_next(struct trace_event_iter *iter);
extern void trace_event_iter_reset(struct trace_event_iter *iter);

extern int trace_event_get_iter_range(struct trace_event * const **trace_event,
				      struct trace_event * const *begin,
				      struct trace_event * const *end);

extern void trace_event_update_process(void);
extern int is_trace_event_enabled(const char *channel, const char *name);

extern int trace_event_register_lib(struct trace_event * const *start_trace_events,
				    int trace_event_count);

extern int trace_event_unregister_lib(struct trace_event * const *start_trace_events);

#define TRACE_EVENT_LIB							\
	extern struct trace_event * const __start___trace_events_ptrs[]	\
	__attribute__((weak, visibility("hidden")));			\
	extern struct trace_event * const __stop___trace_events_ptrs[]	\
	__attribute__((weak, visibility("hidden")));			\
	static struct trace_event * const __event_ptrs_dummy		\
	__attribute__((used, section("__trace_events_ptrs"))) =	NULL;	\
	static void __attribute__((constructor))			\
	__trace_events__init(void)					\
	{								\
		trace_event_register_lib(__start___trace_events_ptrs,	\
					 __stop___trace_events_ptrs -	\
					 __start___trace_events_ptrs);	\
	}								\
									\
	static void __attribute__((destructor))				\
	__trace_event__destroy(void)					\
	{								\
		trace_event_unregister_lib(__start___trace_events_ptrs);\
	}

#define DECLARE_TRACE_EVENT_CLASS(name, proto, args, tstruct, assign, print)
#define DEFINE_TRACE_EVENT(template, name, proto, args)		\
	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
#define DEFINE_TRACE_EVENT_PRINT(template, name, proto, args, print)	\
	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))

#define TRACE_EVENT(name, proto, args, struct, assign, print)	\
	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
#define TRACE_EVENT_FN(name, proto, args, struct,		\
		assign, print, reg, unreg)			\
	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))

#endif /* ifdef TRACE_EVENT (see note above) */


#endif /* _UST_TRACEPOINT_H */
Commit	Line	Data
27b052e3 PMF	1	#ifndef _UST_TRACEPOINT_H
27b052e3 PMF	2	#define _UST_TRACEPOINT_H
f99be407 PMF	3
f99be407 PMF	4	/*
1f8b0dff PMF	5	* Copyright (C) 2008 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
1f8b0dff PMF	6	* Copyright (C) 2009 Pierre-Marc Fournier
22d72948	7	* Copyright (C) 2009 Steven Rostedt <rostedt@goodmis.org>
f99be407	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.
f99be407	13	*
8fc2d8db	14	* This library is distributed in the hope that it will be useful,
1f8b0dff	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
8fc2d8db PMF	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
8fc2d8db PMF	17	* Lesser General Public License for more details.
1f8b0dff	18	*
8fc2d8db PMF	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
f99be407 PMF	22	*
	23	* Heavily inspired from the Linux Kernel Markers.
	24	*
1f8b0dff	25	* Ported to userspace by Pierre-Marc Fournier.
f99be407 PMF	26	*/
f99be407 PMF	27
872037bb	28	#define _LGPL_SOURCE
b7ea1a1c	29	#include <urcu-bp.h>
93d0f2ea	30	#include <ust/immediate.h>
518d7abb	31	#include <ust/core.h>
f99be407 PMF	32
	33	struct module;
	34	struct tracepoint;
	35
9dec086e NC	36	struct probe {
	37	void *func;
	38	void *data;
	39	};
	40
f99be407 PMF	41	struct tracepoint {
	42	const char name; / Tracepoint name */
	43	DEFINE_IMV(char, state); /* State. */
9dec086e	44	struct probe *probes;
f218ff28	45	};
f99be407	46
22d72948 NC	47	#define PARAMS(args...) args
22d72948 NC	48
7166e240 PMF	49	#define TP_PROTO(args...) args
7166e240 PMF	50	#define TP_ARGS(args...) args
f99be407	51
cc7b66ba MD	52	/*
	53	* Tracepoints should be added to the instrumented code using the
	54	* "tracepoint()" macro.
	55	*/
	56	#define tracepoint(name, args...) __trace_##name(args)
	57
	58	#define register_tracepoint(name, probe, data) \
	59	__register_trace_##name(probe, data)
	60
	61	#define unregister_tracepoint(name, probe, data) \
	62	__unregister_trace_##name(probe, data)
	63
872037bb PMF	64	#define CONFIG_TRACEPOINTS
872037bb PMF	65	#ifdef CONFIG_TRACEPOINTS
f99be407 PMF	66
	67	/*
	68	* it_func[0] is never NULL because there is at least one element in the array
	69	* when the array itself is non NULL.
	70	*/
	71	#define __DO_TRACE(tp, proto, args) \
	72	do { \
9dec086e NC	73	struct probe *it_probe_ptr; \
	74	void *it_func; \
	75	void *__data; \
f99be407	76	\
9dec086e NC	77	rcu_read_lock(); \
	78	it_probe_ptr = rcu_dereference((tp)->probes); \
	79	if (it_probe_ptr) { \
f99be407	80	do { \
9dec086e NC	81	it_func = (it_probe_ptr)->func; \
	82	__data = (it_probe_ptr)->data; \
	83	((void(*)(proto))(it_func))(args); \
	84	} while ((++it_probe_ptr)->func); \
f99be407	85	} \
9dec086e	86	rcu_read_unlock(); \
f99be407 PMF	87	} while (0)
	88
	89	#define __CHECK_TRACE(name, generic, proto, args) \
	90	do { \
	91	if (!generic) { \
	92	if (unlikely(imv_read(__tracepoint_##name.state))) \
	93	__DO_TRACE(&__tracepoint_##name, \
7166e240	94	TP_PROTO(proto), TP_ARGS(args)); \
f99be407 PMF	95	} else { \
	96	if (unlikely(_imv_read(__tracepoint_##name.state))) \
	97	__DO_TRACE(&__tracepoint_##name, \
7166e240	98	TP_PROTO(proto), TP_ARGS(args)); \
f99be407 PMF	99	} \
	100	} while (0)
	101
	102	/*
	103	* Make sure the alignment of the structure in the __tracepoints section will
	104	* not add unwanted padding between the beginning of the section and the
	105	* structure. Force alignment to the same alignment as the section start.
	106	*
	107	* The "generic" argument, passed to the declared __trace_##name inline
	108	* function controls which tracepoint enabling mechanism must be used.
	109	* If generic is true, a variable read is used.
	110	* If generic is false, immediate values are used.
	111	*/
9dec086e	112	#define __DECLARE_TRACE(name, proto, args, data_proto, data_args) \
f99be407	113	extern struct tracepoint __tracepoint_##name; \
cc7b66ba	114	static inline void __trace_##name(proto) \
f99be407	115	{ \
9dec086e NC	116	__CHECK_TRACE(name, 0, TP_PROTO(data_proto), \
9dec086e NC	117	TP_ARGS(data_args)); \
f99be407 PMF	118	} \
	119	static inline void _trace_##name(proto) \
	120	{ \
9dec086e NC	121	__CHECK_TRACE(name, 1, TP_PROTO(data_proto), \
9dec086e NC	122	TP_ARGS(data_args)); \
f99be407	123	} \
9dec086e	124	static inline int \
cc7b66ba	125	__register_trace_##name(void (probe)(data_proto), void data) \
f99be407	126	{ \
9dec086e NC	127	return tracepoint_probe_register(#name, (void *)probe, \
	128	data); \
	129	\
f99be407	130	} \
9dec086e	131	static inline int \
cc7b66ba	132	__unregister_trace_##name(void (probe)(data_proto), void data)\
f99be407	133	{ \
9dec086e NC	134	return tracepoint_probe_unregister(#name, (void *)probe, \
9dec086e NC	135	data); \
f99be407 PMF	136	}
f99be407 PMF	137
f218ff28	138	#define DEFINE_TRACE_FN(name, reg, unreg) \
f99be407 PMF	139	static const char __tpstrtab_##name[] \
	140	__attribute__((section("__tracepoints_strings"))) = #name; \
	141	struct tracepoint __tracepoint_##name \
f218ff28 MD	142	__attribute__((section("__tracepoints"))) = \
	143	{ __tpstrtab_##name, 0, NULL }; \
	144	static struct tracepoint * const __tracepoint_ptr_##name \
	145	__attribute__((used, section("__tracepoints_ptrs"))) = \
	146	&__tracepoint_##name;
f99be407	147
9dec086e	148	#define DEFINE_TRACE(name) \
f218ff28	149	DEFINE_TRACE_FN(name, NULL, NULL)
9dec086e	150
f218ff28 MD	151	extern void tracepoint_update_probe_range(struct tracepoint * const *begin,
f218ff28 MD	152	struct tracepoint * const *end);
f99be407	153
872037bb	154	#else /* !CONFIG_TRACEPOINTS */
9dec086e	155	#define __DECLARE_TRACE(name, proto, args) \
872037bb PMF	156	static inline void trace_##name(proto) \
	157	{ } \
	158	static inline void _trace_##name(proto) \
	159	{ } \
cc7b66ba	160	static inline int __register_trace_##name(void (probe)(proto), void data) \
872037bb PMF	161	{ \
	162	return -ENOSYS; \
	163	} \
cc7b66ba	164	static inline int __unregister_trace_##name(void (probe)(proto), void data) \
872037bb PMF	165	{ \
	166	return -ENOSYS; \
	167	}
	168
	169	#define DEFINE_TRACE(name)
	170	#define EXPORT_TRACEPOINT_SYMBOL_GPL(name)
	171	#define EXPORT_TRACEPOINT_SYMBOL(name)
	172
	173	static inline void tracepoint_update_probe_range(struct tracepoint *begin,
	174	struct tracepoint *end)
	175	{ }
	176	#endif /* CONFIG_TRACEPOINTS */
f99be407	177
377d33ed MD	178	/*
	179	* The need for the DECLARE_TRACE_NOARGS() is to handle the prototype
	180	* (void). "void" is a special value in a function prototype and can
	181	* not be combined with other arguments. Since the DECLARE_TRACE()
	182	* macro adds a data element at the beginning of the prototype,
	183	* we need a way to differentiate "(void *data, proto)" from
	184	* "(void *data, void)". The second prototype is invalid.
	185	*
	186	* DECLARE_TRACE_NOARGS() passes "void" as the tracepoint prototype
	187	* and "void *__data" as the callback prototype.
	188	*
	189	* DECLARE_TRACE() passes "proto" as the tracepoint protoype and
	190	* "void *__data, proto" as the callback prototype.
	191	*/
	192	#define DECLARE_TRACE_NOARGS(name) \
	193	__DECLARE_TRACE(name, void, , void *__data, __data)
	194
	195	#define DECLARE_TRACE(name, proto, args) \
	196	__DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \
	197	PARAMS(void *__data, proto), \
	198	PARAMS(__data, args))
9dec086e	199
f99be407 PMF	200	/*
	201	* Connect a probe to a tracepoint.
	202	* Internal API, should not be used directly.
	203	*/
9dec086e	204	extern int tracepoint_probe_register(const char name, void probe, void *data);
f99be407 PMF	205
	206	/*
	207	* Disconnect a probe from a tracepoint.
	208	* Internal API, should not be used directly.
	209	*/
9dec086e	210	extern int tracepoint_probe_unregister(const char name, void probe, void *data);
f99be407	211
9dec086e NC	212	extern int tracepoint_probe_register_noupdate(const char name, void probe,
	213	void *data);
	214	extern int tracepoint_probe_unregister_noupdate(const char name, void probe,
	215	void *data);
f99be407 PMF	216	extern void tracepoint_probe_update_all(void);
	217
	218	struct tracepoint_iter {
474d745f PMF	219	//ust// struct module *module;
474d745f PMF	220	struct tracepoint_lib *lib;
f218ff28	221	struct tracepoint * const *tracepoint;
f99be407 PMF	222	};
	223
	224	extern void tracepoint_iter_start(struct tracepoint_iter *iter);
	225	extern void tracepoint_iter_next(struct tracepoint_iter *iter);
	226	extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
	227	extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
f218ff28 MD	228	extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint,
f218ff28 MD	229	struct tracepoint * const begin, struct tracepoint const *end);
f99be407 PMF	230
	231	/*
	232	* tracepoint_synchronize_unregister must be called between the last tracepoint
	233	* probe unregistration and the end of module exit to make sure there is no
	234	* caller executing a probe when it is freed.
	235	*/
	236	static inline void tracepoint_synchronize_unregister(void)
	237	{
270c6b98	238	//ust// synchronize_sched();
f99be407 PMF	239	}
f99be407 PMF	240
474d745f	241	struct tracepoint_lib {
f218ff28	242	struct tracepoint * const *tracepoints_start;
474d745f	243	int tracepoints_count;
0222e121	244	struct cds_list_head list;
474d745f PMF	245	};
474d745f PMF	246
f218ff28	247	extern int tracepoint_register_lib(struct tracepoint * const *tracepoints_start,
872037bb	248	int tracepoints_count);
f218ff28	249	extern int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start);
872037bb PMF	250
872037bb PMF	251	#define TRACEPOINT_LIB \
bf5fe926 MD	252	extern struct tracepoint * const __start___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \
bf5fe926 MD	253	extern struct tracepoint * const __stop___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \
f08ebbe2 MD	254	static struct tracepoint * const __tracepoint_ptr_dummy \
f08ebbe2 MD	255	__attribute__((used, section("__tracepoints_ptrs"))) = NULL; \
bf5fe926 MD	256	static void __attribute__((constructor)) __tracepoints__init(void) \
bf5fe926 MD	257	{ \
103fffbc MD	258	tracepoint_register_lib(__start___tracepoints_ptrs, \
	259	__stop___tracepoints_ptrs - \
	260	__start___tracepoints_ptrs); \
bf5fe926 MD	261	} \
	262	\
	263	static void __attribute__((destructor)) __tracepoints__destroy(void) \
	264	{ \
103fffbc	265	tracepoint_unregister_lib(__start___tracepoints_ptrs); \
872037bb PMF	266	}
872037bb PMF	267
22d72948 NC	268
	269	#ifndef TRACE_EVENT
	270	/*
	271	* For use with the TRACE_EVENT macro:
	272	*
	273	* We define a tracepoint, its arguments, its printf format
	274	* and its 'fast binary record' layout.
	275	*
	276	* Firstly, name your tracepoint via TRACE_EVENT(name : the
	277	* 'subsystem_event' notation is fine.
	278	*
	279	* Think about this whole construct as the
	280	* 'trace_sched_switch() function' from now on.
	281	*
	282	*
	283	* TRACE_EVENT(sched_switch,
	284	*
	285	* *
	286	* * A function has a regular function arguments
	287	* * prototype, declare it via TP_PROTO():
	288	* *
	289	*
	290	* TP_PROTO(struct rq rq, struct task_struct prev,
	291	* struct task_struct *next),
	292	*
	293	* *
	294	* * Define the call signature of the 'function'.
	295	* * (Design sidenote: we use this instead of a
	296	* * TP_PROTO1/TP_PROTO2/TP_PROTO3 ugliness.)
	297	* *
	298	*
	299	* TP_ARGS(rq, prev, next),
	300	*
	301	* *
	302	* * Fast binary tracing: define the trace record via
	303	* * TP_STRUCT__entry(). You can think about it like a
	304	* * regular C structure local variable definition.
	305	* *
	306	* * This is how the trace record is structured and will
	307	* * be saved into the ring buffer. These are the fields
	308	* * that will be exposed to readers.
	309	* *
	310	* * The declared 'local variable' is called '__entry'
	311	* *
	312	* * __field(pid_t, prev_prid) is equivalent to a standard declariton:
	313	* *
	314	* * pid_t prev_pid;
	315	* *
	316	* * __array(char, prev_comm, TASK_COMM_LEN) is equivalent to:
	317	* *
	318	* * char prev_comm[TASK_COMM_LEN];
	319	* *
	320	*
	321	* TP_STRUCT__entry(
	322	* __array( char, prev_comm, TASK_COMM_LEN )
	323	* __field( pid_t, prev_pid )
	324	* __field( int, prev_prio )
	325	* __array( char, next_comm, TASK_COMM_LEN )
	326	* __field( pid_t, next_pid )
	327	* __field( int, next_prio )
	328	* ),
	329	*
	330	* *
	331	* * Assign the entry into the trace record, by embedding
332	* * a full C statement block into TP_fast_assign(). You
333	* * can refer to the trace record as '__entry' -
334	* * otherwise you can put arbitrary C code in here.
335	* *
336	* * Note: this C code will execute every time a trace event
337	* * happens, on an active tracepoint.
338	* *
339	*
340	* TP_fast_assign(
341	* memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN);
342	* __entry->prev_pid = prev->pid;
343	* __entry->prev_prio = prev->prio;
344	* memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN);
345	* __entry->next_pid = next->pid;
346	* __entry->next_prio = next->prio;
347	* )
348	*
349	* *
350	* * Formatted output of a trace record via TP_printf().
351	* * This is how the tracepoint will appear under debugging
352	* * of tracepoints.
353	* *
354	* * (raw-binary tracing wont actually perform this step.)
355	* *
356	*
357	* TP_printf("task %s:%d [%d] ==> %s:%d [%d]",
358	* __entry->prev_comm, __entry->prev_pid, __entry->prev_prio,
359	* __entry->next_comm, __entry->next_pid, __entry->next_prio),
360	*
361	* );
362	*
363	* This macro construct is thus used for the regular printf format
364	* tracing setup.
365	*
366	* A set of (un)registration functions can be passed to the variant
367	* TRACE_EVENT_FN to perform any (un)registration work.
368	*/
369
0c0686ee NC	370	struct trace_event {
	371	const char *name;
	372	int (regfunc)(void data);
	373	int (unregfunc)(void data);
fc1caebc	374	};
0c0686ee NC	375
0c0686ee NC	376	struct trace_event_lib {
fc1caebc	377	struct trace_event * const *trace_events_start;
0c0686ee	378	int trace_events_count;
0222e121	379	struct cds_list_head list;
0c0686ee NC	380	};
	381
	382	struct trace_event_iter {
	383	struct trace_event_lib *lib;
fc1caebc	384	struct trace_event * const *trace_event;
0c0686ee NC	385	};
	386
	387	extern void lock_trace_events(void);
	388	extern void unlock_trace_events(void);
	389
	390	extern void trace_event_iter_start(struct trace_event_iter *iter);
	391	extern void trace_event_iter_next(struct trace_event_iter *iter);
	392	extern void trace_event_iter_reset(struct trace_event_iter *iter);
	393
fc1caebc MD	394	extern int trace_event_get_iter_range(struct trace_event * const **trace_event,
	395	struct trace_event * const *begin,
	396	struct trace_event * const *end);
0c0686ee NC	397
	398	extern void trace_event_update_process(void);
	399	extern int is_trace_event_enabled(const char channel, const char name);
	400
fc1caebc	401	extern int trace_event_register_lib(struct trace_event * const *start_trace_events,
0c0686ee NC	402	int trace_event_count);
0c0686ee NC	403
fc1caebc	404	extern int trace_event_unregister_lib(struct trace_event * const *start_trace_events);
0c0686ee NC	405
0c0686ee NC	406	#define TRACE_EVENT_LIB \
fc1caebc	407	extern struct trace_event * const __start___trace_events_ptrs[] \
0c0686ee	408	__attribute__((weak, visibility("hidden"))); \
fc1caebc	409	extern struct trace_event * const __stop___trace_events_ptrs[] \
0c0686ee	410	__attribute__((weak, visibility("hidden"))); \
f08ebbe2 MD	411	static struct trace_event * const __event_ptrs_dummy \
f08ebbe2 MD	412	__attribute__((used, section("__trace_events_ptrs"))) = NULL; \
0c0686ee NC	413	static void __attribute__((constructor)) \
	414	__trace_events__init(void) \
	415	{ \
fc1caebc MD	416	trace_event_register_lib(__start___trace_events_ptrs, \
	417	__stop___trace_events_ptrs - \
	418	__start___trace_events_ptrs); \
0c0686ee NC	419	} \
	420	\
	421	static void __attribute__((destructor)) \
	422	__trace_event__destroy(void) \
	423	{ \
fc1caebc	424	trace_event_unregister_lib(__start___trace_events_ptrs);\
0c0686ee NC	425	}
0c0686ee NC	426
22d72948 NC	427	#define DECLARE_TRACE_EVENT_CLASS(name, proto, args, tstruct, assign, print)
	428	#define DEFINE_TRACE_EVENT(template, name, proto, args) \
	429	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
	430	#define DEFINE_TRACE_EVENT_PRINT(template, name, proto, args, print) \
	431	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
	432
	433	#define TRACE_EVENT(name, proto, args, struct, assign, print) \
	434	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
	435	#define TRACE_EVENT_FN(name, proto, args, struct, \
	436	assign, print, reg, unreg) \
	437	DECLARE_TRACE(name, PARAMS(proto), PARAMS(args))
	438
	439	#endif /* ifdef TRACE_EVENT (see note above) */
	440
	441
27b052e3	442	#endif /* _UST_TRACEPOINT_H */