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

#ifndef _LTTNG_TRACEPOINT_H
#define _LTTNG_TRACEPOINT_H

/*
 * Copyright (C) 2008-2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 * 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;
 * version 2.1 of the License.
 *
 * 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.
 */

#include <urcu-bp.h>
#include <urcu/list.h>
#include <lttng/tracepoint-types.h>

#ifdef __cplusplus
extern "C" {
#endif

/*
 * Tracepoints should be added to the instrumented code using the
 * "tracepoint()" macro.
 */
#define tracepoint(provider, name, args...)					\
	do {									\
		if (caa_unlikely(__tracepoint_##provider##___##name.state))	\
			__trace_##provider##___##name(args);			\
	} while (0)

/*
 * 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, vars)					\
	do {								\
		struct tracepoint_probe *__tp_it_probe_ptr;		\
		void *__tp_it_func;					\
		void *__tp_cb_data;					\
									\
		rcu_read_lock();					\
		__tp_it_probe_ptr = rcu_dereference((tp)->probes);	\
		if (__tp_it_probe_ptr) {				\
			do {						\
				__tp_it_func = __tp_it_probe_ptr->func;	\
				__tp_cb_data = __tp_it_probe_ptr->data;	\
				URCU_FORCE_CAST(void(*)(proto), __tp_it_func)(vars); \
			} while ((++__tp_it_probe_ptr)->func);		\
		}							\
		rcu_read_unlock();					\
	} while (0)

#define TP_PARAMS(args...)	args
#define TP_ARGS(args...)	args

/*
 * TP_ARGS takes tuples of type, argument separated by a comma. It can
 * take up to 10 tuples (which means that less than 10 tuples is fine
 * too). Each tuple is also separated by a comma.
 */

#define TP_COMBINE_TOKENS1(_tokena, _tokenb)       _tokena##_tokenb
#define TP_COMBINE_TOKENS(_tokena, _tokenb)        TP_COMBINE_TOKENS1(_tokena, _tokenb)

/* _TP_EVEN* extracts the vars names. */
/* 0 and 1 are for void */
#define _TP_EVEN0()
#define _TP_EVEN1(a)
#define _TP_EVEN2(a,b)						b
#define _TP_EVEN4(a,b,c,d)					b,d
#define _TP_EVEN6(a,b,c,d,e,f)					b,d,f
#define _TP_EVEN8(a,b,c,d,e,f,g,h)				b,d,f,h
#define _TP_EVEN10(a,b,c,d,e,f,g,h,i,j)				b,d,f,h,j
#define _TP_EVEN12(a,b,c,d,e,f,g,h,i,j,k,l)			b,d,f,h,j,l
#define _TP_EVEN14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)			b,d,f,h,j,l,n
#define _TP_EVEN16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)		b,d,f,h,j,l,n,p
#define _TP_EVEN18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)		b,d,f,h,j,l,n,p,r
#define _TP_EVEN20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)	b,d,f,h,j,l,n,p,r,t

/* 0 and 1 are for void */
#define _TP_EVEN_DATA0()						__tp_cb_data
#define _TP_EVEN_DATA1(a)						__tp_cb_data
#define _TP_EVEN_DATA2(a,b)						__tp_cb_data,b
#define _TP_EVEN_DATA4(a,b,c,d)						__tp_cb_data,b,d
#define _TP_EVEN_DATA6(a,b,c,d,e,f)					__tp_cb_data,b,d,f
#define _TP_EVEN_DATA8(a,b,c,d,e,f,g,h)					__tp_cb_data,b,d,f,h
#define _TP_EVEN_DATA10(a,b,c,d,e,f,g,h,i,j)				__tp_cb_data,b,d,f,h,j
#define _TP_EVEN_DATA12(a,b,c,d,e,f,g,h,i,j,k,l)			__tp_cb_data,b,d,f,h,j,l
#define _TP_EVEN_DATA14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)			__tp_cb_data,b,d,f,h,j,l,n
#define _TP_EVEN_DATA16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)		__tp_cb_data,b,d,f,h,j,l,n,p
#define _TP_EVEN_DATA18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)		__tp_cb_data,b,d,f,h,j,l,n,p,r
#define _TP_EVEN_DATA20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)	__tp_cb_data,b,d,f,h,j,l,n,p,r,t

/* _TP_SPLIT extracts tuples of type, var */
/* 0 and 1 are for void */
#define _TP_SPLIT0()
#define _TP_SPLIT1(a)
#define _TP_SPLIT2(a,b)						a b
#define _TP_SPLIT4(a,b,c,d)					a b,c d
#define _TP_SPLIT6(a,b,c,d,e,f)					a b,c d,e f
#define _TP_SPLIT8(a,b,c,d,e,f,g,h)				a b,c d,e f,g h
#define _TP_SPLIT10(a,b,c,d,e,f,g,h,i,j)			a b,c d,e f,g h,i j
#define _TP_SPLIT12(a,b,c,d,e,f,g,h,i,j,k,l)			a b,c d,e f,g h,i j,k l
#define _TP_SPLIT14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)		a b,c d,e f,g h,i j,k l,m n
#define _TP_SPLIT16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)		a b,c d,e f,g h,i j,k l,m n,o p
#define _TP_SPLIT18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)	a b,c d,e f,g h,i j,k l,m n,o p,q r
#define _TP_SPLIT20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)	a b,c d,e f,g h,i j,k l,m n,o p,q r,s t

/* 0 and 1 are for void */
#define _TP_SPLIT_DATA0()						void *__tp_cb_data
#define _TP_SPLIT_DATA1(a)						void *__tp_cb_data
#define _TP_SPLIT_DATA2(a,b)						void *__tp_cb_data,a b
#define _TP_SPLIT_DATA4(a,b,c,d)					void *__tp_cb_data,a b,c d
#define _TP_SPLIT_DATA6(a,b,c,d,e,f)					void *__tp_cb_data,a b,c d,e f
#define _TP_SPLIT_DATA8(a,b,c,d,e,f,g,h)				void *__tp_cb_data,a b,c d,e f,g h
#define _TP_SPLIT_DATA10(a,b,c,d,e,f,g,h,i,j)				void *__tp_cb_data,a b,c d,e f,g h,i j
#define _TP_SPLIT_DATA12(a,b,c,d,e,f,g,h,i,j,k,l)			void *__tp_cb_data,a b,c d,e f,g h,i j,k l
#define _TP_SPLIT_DATA14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)			void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n
#define _TP_SPLIT_DATA16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)		void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n,o p
#define _TP_SPLIT_DATA18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)		void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n,o p,q r
#define _TP_SPLIT_DATA20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)	void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n,o p,q r,s t

/* Preprocessor trick to count arguments. Inspired from sdt.h. */
#define _TP_NARGS(...)	__TP_NARGS(__VA_ARGS__, 20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0)
#define __TP_NARGS(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20, N, ...) N
#define _TP_PROTO_N(N, ...)	\
	TP_PARAMS(TP_COMBINE_TOKENS(_TP_SPLIT, N)(__VA_ARGS__))
#define _TP_VARS_N(N, ...)	\
	TP_PARAMS(TP_COMBINE_TOKENS(_TP_EVEN, N)(__VA_ARGS__))
#define _TP_PROTO_DATA_N(N, ...)	\
	TP_PARAMS(TP_COMBINE_TOKENS(_TP_SPLIT_DATA, N)(__VA_ARGS__))
#define _TP_VARS_DATA_N(N, ...)	\
	TP_PARAMS(TP_COMBINE_TOKENS(_TP_EVEN_DATA, N)(__VA_ARGS__))

#define _TP_ARGS_PROTO(...)		_TP_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
#define _TP_ARGS_VARS(...)		_TP_VARS_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)

#define _TP_ARGS_PROTO_DATA(...)	_TP_PROTO_DATA_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
#define _TP_ARGS_VARS_DATA(...)		_TP_VARS_DATA_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)

/*
 * 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.
 */
#define __DECLARE_TRACEPOINT(provider, name, proto, args, data_proto, data_args)	\
	extern struct tracepoint __tracepoint_##provider##___##name;	\
	static inline void __trace_##provider##___##name(proto)		\
	{								\
		__DO_TRACE(&__tracepoint_##provider##___##name,		\
			TP_PARAMS(data_proto), TP_PARAMS(data_args));	\
	}								\
	static inline int						\
	__register_trace_##provider##___##name(void (*probe)(data_proto), void *data)	\
	{								\
		return __tracepoint_probe_register(#provider ":" #name, (void *) probe,	\
						 data);			\
	}								\
	static inline int						\
	__unregister_trace_##provider##___##name(void (*probe)(data_proto), void *data)	\
	{								\
		return __tracepoint_probe_unregister(#provider ":" #name, (void *) probe, \
						   data);		\
	}

#define _DECLARE_TRACEPOINT(provider, name, args)			\
	__DECLARE_TRACEPOINT(provider, name, _TP_ARGS_PROTO(args), _TP_ARGS_VARS(args),	\
			_TP_ARGS_PROTO_DATA(args), _TP_ARGS_VARS_DATA(args))

/*
 * __tracepoints_ptrs section is not const (read-only) to let the linker update
 * the pointer, allowing PIC code.
 */
#define _DEFINE_TRACEPOINT(provider, name)				\
	static const char __tpstrtab_##provider##___##name[]		\
	__attribute__((section("__tracepoints_strings"))) =		\
		#provider ":" #name;					\
	struct tracepoint __tracepoint_##provider##___##name		\
	__attribute__((section("__tracepoints"))) =			\
		{ __tpstrtab_##provider##___##name, 0, NULL };		\
	static struct tracepoint * __tracepoint_ptr_##provider##___##name	\
	__attribute__((used, section("__tracepoints_ptrs"))) =		\
		&__tracepoint_##provider##___##name;


#define __register_tracepoint(provider, name, probe, data)		\
		__register_trace_##provider##___##name(probe, data)
#define __unregister_tracepoint(provider, name, probe, data)		\
		__unregister_trace_##provider##___##name(probe, data)

/*
 * Connect a probe to a tracepoint.
 * Internal API.
 */
extern
int __tracepoint_probe_register(const char *name, void *probe, void *data);

/*
 * Disconnect a probe from a tracepoint.
 * Internal API.
 */
extern
int __tracepoint_probe_unregister(const char *name, void *probe, void *data);

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

/*
 * These weak symbols, the constructor, and destructor take care of
 * registering only _one_ instance of the tracepoints per shared-ojbect
 * (or for the whole main program).
 */
extern struct tracepoint * const __start___tracepoints_ptrs[]
	__attribute__((weak, visibility("hidden")));
extern struct tracepoint * const __stop___tracepoints_ptrs[]
	__attribute__((weak, visibility("hidden")));
int __tracepoint_registered
	__attribute__((weak, visibility("hidden")));

static void __attribute__((constructor)) __tracepoints__init(void)
{
	if (__tracepoint_registered++)
		return;
	tracepoint_register_lib(__start___tracepoints_ptrs,
				__stop___tracepoints_ptrs -
				__start___tracepoints_ptrs);
}

static void __attribute__((destructor)) __tracepoints__destroy(void)
{
	if (--__tracepoint_registered)
		return;
	tracepoint_unregister_lib(__start___tracepoints_ptrs);
}

#ifdef __cplusplus 
}
#endif

#endif /* _LTTNG_TRACEPOINT_H */

/*
 * For multiple probe generation, we need to redefine TRACEPOINT_EVENT
 * each time tracepoint.h is included.
 */

#ifndef TRACEPOINT_EVENT
/*
 * Usage of the TRACEPOINT_EVENT macro:
 *
 * In short, an example:
 *
 * TRACEPOINT_EVENT(< [com_company_]project[_component] >, < event >,
 *
 *     * TP_ARGS takes from 0 to 10 "type, field_name" pairs *
 *
 *     TP_ARGS(int, arg0, void *, arg1, char *, string, size_t, strlen,
 *             long *, arg4, size_t, arg4_len),
 *     TP_FIELDS(
 *
 *         * Integer, printed in base 10 * 
 *         ctf_integer(int, field_a, arg0)
 *
 *         * Integer, printed with 0x base 16 * 
 *         ctf_integer_hex(unsigned long, field_d, arg1)
 *
 *         * Array Sequence, printed as UTF8-encoded array of bytes * 
 *         ctf_array_text(char, field_b, string, FIXED_LEN)
 *         ctf_sequence_text(char, field_c, string, size_t, strlen)
 *
 *         * String, printed as UTF8-encoded string * 
 *         ctf_string(field_e, string)
 *
 *         * Array sequence of signed integer values * 
 *         ctf_array(long, field_f, arg4, FIXED_LEN4)
 *         ctf_sequence(long, field_g, arg4, size_t, arg4_len)
 *     )
 * )
 *
 * In more detail:
 *
 * We define a tracepoint, its arguments, and its 'fast binary record'
 * layout.
 *
 * Firstly, name your tracepoint via TRACEPOINT_EVENT(provider, name,
 *
 * The provider and name should be a proper C99 identifier.
 * The "provider" and "name" MUST follow these rules to ensure no
 * namespace clash occurs:
 *
 * For projects (applications and libraries) for which an entity
 * specific to the project controls the source code and thus its
 * tracepoints (typically with a scope larger than a single company):
 *
 * either:
 *   project_component, event
 * or:
 *   project, event
 *
 * Where "project" is the name of the project,
 *       "component" is the name of the project component (which may
 *       include several levels of sub-components, e.g.
 *       ...component_subcomponent_...) where the tracepoint is located
 *       (optional),
 *       "event" is the name of the tracepoint event.
 *
 * For projects issued from a single company wishing to advertise that
 * the company controls the source code and thus the tracepoints, the
 * "com_" prefix should be used:
 *
 * either:
 *   com_company_project_component, event
 * or:
 *   com_company_project, event
 *
 * Where "company" is the name of the company,
 *       "project" is the name of the project,
 *       "component" is the name of the project component (which may
 *       include several levels of sub-components, e.g.
 *       ...component_subcomponent_...) where the tracepoint is located
 *       (optional),
 *       "event" is the name of the tracepoint event.
 *
 * the provider:event identifier is limited to 127 characters.
 *
 * As an example, let's consider a user-space application "someproject"
 * that would have an internal thread scheduler:
 *
 *  TRACEPOINT_EVENT(someproject_sched, switch,
 *
 *	*
 *	* Arguments to pass to the tracepoint. Supports from
 *	* 0 to 10 "type, name" tuples.
 *	*
 *
 *	TP_ARGS(struct rq *, rq, struct task_struct *, prev,
 *		struct task_struct *, next),
 *
 *	*
 *	* Fast binary tracing: define the trace record via
 *	* TP_FIELDS(). 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.
 *	*
 *	* ctf_integer(pid_t, prev_pid, prev->pid) is equivalent
 *	* to a standard declaraton:
 *	*
 *	*	pid_t prev_pid;
 *	*
 *	* followed by an assignment:
 *	*
 *	*	prev_pid = prev->pid;
 *	*
 *	* ctf_array(char, prev_comm, prev->comm, TASK_COMM_LEN) is
 *	* equivalent to:
 *	*
 *	*	char prev_comm[TASK_COMM_LEN];
 *	*
 *	* followed by an assignment:
 *	*
 *	*	memcpy(prev_comm, prev->comm, TASK_COMM_LEN);
 *	*
 *
 *	TP_FIELDS(
 *		ctf_array(char, prev_comm, prev->comm, TASK_COMM_LEN)
 *		ctf_integer(pid_t, prev_pid,  prev->pid)
 *		ctf_integer(int, prev_prio, prev->prio)
 *		ctf_array(char, next_comm, next->comm, TASK_COMM_LEN)
 *		ctf_integer(pid_t, next_pid,  next->pid)
 *		ctf_integer(int, next_prio, next->prio)
 *	)
 * )
 *
 * Do _NOT_ add comma (,) nor semicolon (;) after the TRACEPOINT_EVENT
 * declaration.
 *
 * The TRACEPOINT_PROVIDER must be defined when declaring a
 * TRACEPOINT_EVENT. See ust/tracepoint-event.h for information about
 * usage of other macros controlling TRACEPOINT_EVENT.
 */

#define TRACEPOINT_EVENT(provider, name, args, fields)		\
	_DECLARE_TRACEPOINT(provider, name, TP_PARAMS(args))

#define TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
#define TRACEPOINT_EVENT_INSTANCE(provider, template, name, args)\
	_DECLARE_TRACEPOINT(provider, name, TP_PARAMS(args))

#endif /* #ifndef TRACEPOINT_EVENT */

#ifndef TRACEPOINT_LOGLEVEL

/*
 * Tracepoint Loglevel Declaration Facility
 *
 * This is a place-holder the tracepoint loglevel declaration,
 * overridden by the tracer implementation.
 *
 * Typical use of these loglevels:
 *
 * 1) Declare the mapping between loglevel names and an integer values
 *    within TRACEPOINT_LOGLEVEL_ENUM, using TP_LOGLEVEL for each tuple.
 *    Do _NOT_ add comma (,) nor semicolon (;) between the
 *    TRACEPOINT_LOGLEVEL_ENUM entries. Do _NOT_ add comma (,) nor
 *    semicolon (;) after the TRACEPOINT_LOGLEVEL_ENUM declaration.  The
 *    name should be a proper C99 identifier.
 *
 *      TRACEPOINT_LOGLEVEL_ENUM(
 *              TP_LOGLEVEL( < loglevel_name >, < value > )
 *              TP_LOGLEVEL( < loglevel_name >, < value > )
 *              ...
 *      )
 *
 *    e.g.:
 *
 *      TRACEPOINT_LOGLEVEL_ENUM(
 *              TP_LOGLEVEL(LOG_EMERG,   0)
 *              TP_LOGLEVEL(LOG_ALERT,   1)
 *              TP_LOGLEVEL(LOG_CRIT,    2)
 *              TP_LOGLEVEL(LOG_ERR,     3)
 *              TP_LOGLEVEL(LOG_WARNING, 4)
 *              TP_LOGLEVEL(LOG_NOTICE,  5)
 *              TP_LOGLEVEL(LOG_INFO,    6)
 *              TP_LOGLEVEL(LOG_DEBUG,   7)
 *      )
 *
 * 2) Then, declare tracepoint loglevels for tracepoints. A
 *    TRACEPOINT_EVENT should be declared prior to the the
 *    TRACEPOINT_LOGLEVEL for a given tracepoint name. The first field
 *    is the name of the tracepoint, the second field is the loglevel
 *    name.
 *
 *      TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
 *              < loglevel_name >)
 *
 * The TRACEPOINT_PROVIDER must be defined when declaring a
 * TRACEPOINT_LOGLEVEL_ENUM and TRACEPOINT_LOGLEVEL. The tracepoint
 * loglevel enumeration apply to the entire TRACEPOINT_PROVIDER. Only one
 * tracepoint loglevel enumeration should be declared per tracepoint
 * provider.
 */

#define TRACEPOINT_LOGLEVEL_ENUM()
#define TRACEPOINT_LOGLEVEL(name, loglevel)

#endif /* #ifndef TRACEPOINT_LOGLEVEL */
Commit	Line	Data
51489cad MD	1	#ifndef _LTTNG_TRACEPOINT_H
51489cad MD	2	#define _LTTNG_TRACEPOINT_H
f99be407 PMF	3
f99be407 PMF	4	/*
e9090899	5	* Copyright (C) 2008-2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
1f8b0dff	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
8fc2d8db PMF	10	* modify it under the terms of the GNU Lesser General Public
f37142a4 MD	11	* License as published by the Free Software Foundation;
f37142a4 MD	12	* version 2.1 of the License.
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	*
f99be407 PMF	23	* Heavily inspired from the Linux Kernel Markers.
f99be407 PMF	24	*/
f99be407 PMF	25
b7ea1a1c	26	#include <urcu-bp.h>
b0c4126f	27	#include <urcu/list.h>
51489cad	28	#include <lttng/tracepoint-types.h>
f99be407	29
1ea2c2df MD	30	#ifdef __cplusplus
	31	extern "C" {
	32	#endif
	33
cc7b66ba MD	34	/*
	35	* Tracepoints should be added to the instrumented code using the
	36	* "tracepoint()" macro.
	37	*/
82fa766d MD	38	#define tracepoint(provider, name, args...) \
	39	do { \
	40	if (caa_unlikely(__tracepoint_##provider##___##name.state)) \
	41	__trace_##provider##___##name(args); \
	42	} while (0)
cc7b66ba	43
f99be407 PMF	44	/*
	45	* it_func[0] is never NULL because there is at least one element in the array
	46	* when the array itself is non NULL.
	47	*/
63ef2693	48	#define __DO_TRACE(tp, proto, vars) \
f99be407	49	do { \
b979b346 MD	50	struct tracepoint_probe *__tp_it_probe_ptr; \
	51	void *__tp_it_func; \
	52	void *__tp_cb_data; \
f99be407	53	\
9dec086e	54	rcu_read_lock(); \
b979b346 MD	55	__tp_it_probe_ptr = rcu_dereference((tp)->probes); \
b979b346 MD	56	if (__tp_it_probe_ptr) { \
f99be407	57	do { \
b979b346 MD	58	__tp_it_func = __tp_it_probe_ptr->func; \
b979b346 MD	59	__tp_cb_data = __tp_it_probe_ptr->data; \
63ef2693	60	URCU_FORCE_CAST(void(*)(proto), __tp_it_func)(vars); \
b979b346	61	} while ((++__tp_it_probe_ptr)->func); \
f99be407	62	} \
9dec086e	63	rcu_read_unlock(); \
f99be407 PMF	64	} while (0)
f99be407 PMF	65
81614639	66	#define TP_PARAMS(args...) args
63ef2693 MD	67	#define TP_ARGS(args...) args
	68
	69	/*
	70	* TP_ARGS takes tuples of type, argument separated by a comma. It can
	71	* take up to 10 tuples (which means that less than 10 tuples is fine
	72	* too). Each tuple is also separated by a comma.
	73	*/
	74
	75	#define TP_COMBINE_TOKENS1(_tokena, _tokenb) _tokena##_tokenb
	76	#define TP_COMBINE_TOKENS(_tokena, _tokenb) TP_COMBINE_TOKENS1(_tokena, _tokenb)
	77
	78	/* _TP_EVEN* extracts the vars names. */
992abe11	79	/* 0 and 1 are for void */
63ef2693	80	#define _TP_EVEN0()
992abe11	81	#define _TP_EVEN1(a)
63ef2693 MD	82	#define _TP_EVEN2(a,b) b
	83	#define _TP_EVEN4(a,b,c,d) b,d
	84	#define _TP_EVEN6(a,b,c,d,e,f) b,d,f
	85	#define _TP_EVEN8(a,b,c,d,e,f,g,h) b,d,f,h
	86	#define _TP_EVEN10(a,b,c,d,e,f,g,h,i,j) b,d,f,h,j
	87	#define _TP_EVEN12(a,b,c,d,e,f,g,h,i,j,k,l) b,d,f,h,j,l
	88	#define _TP_EVEN14(a,b,c,d,e,f,g,h,i,j,k,l,m,n) b,d,f,h,j,l,n
	89	#define _TP_EVEN16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p) b,d,f,h,j,l,n,p
	90	#define _TP_EVEN18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r) b,d,f,h,j,l,n,p,r
	91	#define _TP_EVEN20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t) b,d,f,h,j,l,n,p,r,t
	92
992abe11	93	/* 0 and 1 are for void */
63ef2693	94	#define _TP_EVEN_DATA0() __tp_cb_data
992abe11	95	#define _TP_EVEN_DATA1(a) __tp_cb_data
63ef2693 MD	96	#define _TP_EVEN_DATA2(a,b) __tp_cb_data,b
	97	#define _TP_EVEN_DATA4(a,b,c,d) __tp_cb_data,b,d
	98	#define _TP_EVEN_DATA6(a,b,c,d,e,f) __tp_cb_data,b,d,f
	99	#define _TP_EVEN_DATA8(a,b,c,d,e,f,g,h) __tp_cb_data,b,d,f,h
	100	#define _TP_EVEN_DATA10(a,b,c,d,e,f,g,h,i,j) __tp_cb_data,b,d,f,h,j
	101	#define _TP_EVEN_DATA12(a,b,c,d,e,f,g,h,i,j,k,l) __tp_cb_data,b,d,f,h,j,l
	102	#define _TP_EVEN_DATA14(a,b,c,d,e,f,g,h,i,j,k,l,m,n) __tp_cb_data,b,d,f,h,j,l,n
	103	#define _TP_EVEN_DATA16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p) __tp_cb_data,b,d,f,h,j,l,n,p
	104	#define _TP_EVEN_DATA18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r) __tp_cb_data,b,d,f,h,j,l,n,p,r
	105	#define _TP_EVEN_DATA20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t) __tp_cb_data,b,d,f,h,j,l,n,p,r,t
	106
	107	/* _TP_SPLIT extracts tuples of type, var */
992abe11	108	/* 0 and 1 are for void */
63ef2693	109	#define _TP_SPLIT0()
992abe11	110	#define _TP_SPLIT1(a)
63ef2693 MD	111	#define _TP_SPLIT2(a,b) a b
	112	#define _TP_SPLIT4(a,b,c,d) a b,c d
	113	#define _TP_SPLIT6(a,b,c,d,e,f) a b,c d,e f
	114	#define _TP_SPLIT8(a,b,c,d,e,f,g,h) a b,c d,e f,g h
	115	#define _TP_SPLIT10(a,b,c,d,e,f,g,h,i,j) a b,c d,e f,g h,i j
	116	#define _TP_SPLIT12(a,b,c,d,e,f,g,h,i,j,k,l) a b,c d,e f,g h,i j,k l
	117	#define _TP_SPLIT14(a,b,c,d,e,f,g,h,i,j,k,l,m,n) a b,c d,e f,g h,i j,k l,m n
	118	#define _TP_SPLIT16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p) a b,c d,e f,g h,i j,k l,m n,o p
	119	#define _TP_SPLIT18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r) a b,c d,e f,g h,i j,k l,m n,o p,q r
	120	#define _TP_SPLIT20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t) a b,c d,e f,g h,i j,k l,m n,o p,q r,s t
	121
992abe11	122	/* 0 and 1 are for void */
63ef2693	123	#define _TP_SPLIT_DATA0() void *__tp_cb_data
992abe11	124	#define _TP_SPLIT_DATA1(a) void *__tp_cb_data
63ef2693 MD	125	#define _TP_SPLIT_DATA2(a,b) void *__tp_cb_data,a b
	126	#define _TP_SPLIT_DATA4(a,b,c,d) void *__tp_cb_data,a b,c d
	127	#define _TP_SPLIT_DATA6(a,b,c,d,e,f) void *__tp_cb_data,a b,c d,e f
	128	#define _TP_SPLIT_DATA8(a,b,c,d,e,f,g,h) void *__tp_cb_data,a b,c d,e f,g h
	129	#define _TP_SPLIT_DATA10(a,b,c,d,e,f,g,h,i,j) void *__tp_cb_data,a b,c d,e f,g h,i j
	130	#define _TP_SPLIT_DATA12(a,b,c,d,e,f,g,h,i,j,k,l) void *__tp_cb_data,a b,c d,e f,g h,i j,k l
	131	#define _TP_SPLIT_DATA14(a,b,c,d,e,f,g,h,i,j,k,l,m,n) void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n
	132	#define _TP_SPLIT_DATA16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p) void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n,o p
	133	#define _TP_SPLIT_DATA18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r) void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n,o p,q r
	134	#define _TP_SPLIT_DATA20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t) void *__tp_cb_data,a b,c d,e f,g h,i j,k l,m n,o p,q r,s t
	135
	136	/* Preprocessor trick to count arguments. Inspired from sdt.h. */
	137	#define _TP_NARGS(...) __TP_NARGS(__VA_ARGS__, 20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0)
	138	#define __TP_NARGS(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20, N, ...) N
	139	#define _TP_PROTO_N(N, ...) \
	140	TP_PARAMS(TP_COMBINE_TOKENS(_TP_SPLIT, N)(__VA_ARGS__))
	141	#define _TP_VARS_N(N, ...) \
	142	TP_PARAMS(TP_COMBINE_TOKENS(_TP_EVEN, N)(__VA_ARGS__))
	143	#define _TP_PROTO_DATA_N(N, ...) \
	144	TP_PARAMS(TP_COMBINE_TOKENS(_TP_SPLIT_DATA, N)(__VA_ARGS__))
	145	#define _TP_VARS_DATA_N(N, ...) \
	146	TP_PARAMS(TP_COMBINE_TOKENS(_TP_EVEN_DATA, N)(__VA_ARGS__))
	147
	148	#define _TP_ARGS_PROTO(...) _TP_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
	149	#define _TP_ARGS_VARS(...) _TP_VARS_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
	150
	151	#define _TP_ARGS_PROTO_DATA(...) _TP_PROTO_DATA_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
	152	#define _TP_ARGS_VARS_DATA(...) _TP_VARS_DATA_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
81614639	153
f99be407 PMF	154	/*
	155	* Make sure the alignment of the structure in the __tracepoints section will
	156	* not add unwanted padding between the beginning of the section and the
	157	* structure. Force alignment to the same alignment as the section start.
f99be407	158	*/
7083f0fe MD	159	#define __DECLARE_TRACEPOINT(provider, name, proto, args, data_proto, data_args) \
	160	extern struct tracepoint __tracepoint_##provider##___##name; \
	161	static inline void __trace_##provider##___##name(proto) \
f99be407	162	{ \
82fa766d MD	163	__DO_TRACE(&__tracepoint_##provider##___##name, \
82fa766d MD	164	TP_PARAMS(data_proto), TP_PARAMS(data_args)); \
f99be407	165	} \
9dec086e	166	static inline int \
7083f0fe	167	__register_trace_##provider##___##name(void (probe)(data_proto), void data) \
f99be407	168	{ \
7083f0fe	169	return __tracepoint_probe_register(#provider ":" #name, (void *) probe, \
9dec086e	170	data); \
f99be407	171	} \
9dec086e	172	static inline int \
7083f0fe	173	__unregister_trace_##provider##___##name(void (probe)(data_proto), void data) \
f99be407	174	{ \
7083f0fe	175	return __tracepoint_probe_unregister(#provider ":" #name, (void *) probe, \
9dec086e	176	data); \
f99be407 PMF	177	}
f99be407 PMF	178
63ef2693 MD	179	#define _DECLARE_TRACEPOINT(provider, name, args) \
	180	__DECLARE_TRACEPOINT(provider, name, _TP_ARGS_PROTO(args), _TP_ARGS_VARS(args), \
	181	_TP_ARGS_PROTO_DATA(args), _TP_ARGS_VARS_DATA(args))
9dec086e	182
f99be407	183	/*
81614639 MD	184	* __tracepoints_ptrs section is not const (read-only) to let the linker update
81614639 MD	185	* the pointer, allowing PIC code.
f99be407	186	*/
7083f0fe MD	187	#define _DEFINE_TRACEPOINT(provider, name) \
	188	static const char __tpstrtab_##provider##___##name[] \
	189	__attribute__((section("__tracepoints_strings"))) = \
	190	#provider ":" #name; \
	191	struct tracepoint __tracepoint_##provider##___##name \
81614639	192	__attribute__((section("__tracepoints"))) = \
7083f0fe MD	193	{ __tpstrtab_##provider##___##name, 0, NULL }; \
7083f0fe MD	194	static struct tracepoint * __tracepoint_ptr_##provider##___##name \
81614639	195	__attribute__((used, section("__tracepoints_ptrs"))) = \
7083f0fe	196	&__tracepoint_##provider##___##name;
f99be407	197
f99be407	198
7083f0fe MD	199	#define __register_tracepoint(provider, name, probe, data) \
	200	__register_trace_##provider##___##name(probe, data)
	201	#define __unregister_tracepoint(provider, name, probe, data) \
	202	__unregister_trace_##provider##___##name(probe, data)
f99be407	203
81614639 MD	204	/*
	205	* Connect a probe to a tracepoint.
	206	* Internal API.
	207	*/
	208	extern
	209	int __tracepoint_probe_register(const char name, void probe, void *data);
f99be407 PMF	210
f99be407 PMF	211	/*
81614639 MD	212	* Disconnect a probe from a tracepoint.
81614639 MD	213	* Internal API.
f99be407	214	*/
81614639 MD	215	extern
81614639 MD	216	int __tracepoint_probe_unregister(const char name, void probe, void *data);
f99be407	217
81614639 MD	218	extern
	219	int tracepoint_register_lib(struct tracepoint * const *tracepoints_start,
	220	int tracepoints_count);
	221	extern
	222	int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start);
872037bb	223
6cdf29f8 MD	224	/*
	225	* These weak symbols, the constructor, and destructor take care of
	226	* registering only _one_ instance of the tracepoints per shared-ojbect
	227	* (or for the whole main program).
6cdf29f8 MD	228	*/
	229	extern struct tracepoint * const __start___tracepoints_ptrs[]
	230	__attribute__((weak, visibility("hidden")));
	231	extern struct tracepoint * const __stop___tracepoints_ptrs[]
	232	__attribute__((weak, visibility("hidden")));
	233	int __tracepoint_registered
	234	__attribute__((weak, visibility("hidden")));
	235
	236	static void __attribute__((constructor)) __tracepoints__init(void)
	237	{
	238	if (__tracepoint_registered++)
	239	return;
	240	tracepoint_register_lib(__start___tracepoints_ptrs,
	241	__stop___tracepoints_ptrs -
	242	__start___tracepoints_ptrs);
	243	}
	244
	245	static void __attribute__((destructor)) __tracepoints__destroy(void)
	246	{
	247	if (--__tracepoint_registered)
	248	return;
	249	tracepoint_unregister_lib(__start___tracepoints_ptrs);
	250	}
22d72948	251
9e0e41bf MD	252	#ifdef __cplusplus
	253	}
	254	#endif
	255
	256	#endif /* _LTTNG_TRACEPOINT_H */
	257
	258	/*
	259	* For multiple probe generation, we need to redefine TRACEPOINT_EVENT
	260	* each time tracepoint.h is included.
	261	*/
	262
8d71973c	263	#ifndef TRACEPOINT_EVENT
22d72948	264	/*
d75775a6 MD	265	* Usage of the TRACEPOINT_EVENT macro:
	266	*
	267	* In short, an example:
	268	*
7083f0fe	269	* TRACEPOINT_EVENT(< [com_company_]project[_component] >, < event >,
63ef2693 MD	270	*
	271	* * TP_ARGS takes from 0 to 10 "type, field_name" pairs *
	272	*
	273	* TP_ARGS(int, arg0, void , arg1, char , string, size_t, strlen,
	274	* long *, arg4, size_t, arg4_len),
d75775a6 MD	275	* TP_FIELDS(
	276	*
	277	* * Integer, printed in base 10 *
	278	* ctf_integer(int, field_a, arg0)
	279	*
	280	* * Integer, printed with 0x base 16 *
	281	* ctf_integer_hex(unsigned long, field_d, arg1)
	282	*
	283	* * Array Sequence, printed as UTF8-encoded array of bytes *
	284	* ctf_array_text(char, field_b, string, FIXED_LEN)
	285	* ctf_sequence_text(char, field_c, string, size_t, strlen)
	286	*
	287	* * String, printed as UTF8-encoded string *
	288	* ctf_string(field_e, string)
	289	*
	290	* * Array sequence of signed integer values *
	291	* ctf_array(long, field_f, arg4, FIXED_LEN4)
	292	* ctf_sequence(long, field_g, arg4, size_t, arg4_len)
	293	* )
	294	* )
	295	*
	296	* In more detail:
22d72948	297	*
0a42beb6 MD	298	* We define a tracepoint, its arguments, and its 'fast binary record'
0a42beb6 MD	299	* layout.
22d72948	300	*
7083f0fe	301	* Firstly, name your tracepoint via TRACEPOINT_EVENT(provider, name,
22d72948	302	*
7083f0fe MD	303	* The provider and name should be a proper C99 identifier.
	304	* The "provider" and "name" MUST follow these rules to ensure no
	305	* namespace clash occurs:
22d72948	306	*
0a42beb6 MD	307	* For projects (applications and libraries) for which an entity
	308	* specific to the project controls the source code and thus its
	309	* tracepoints (typically with a scope larger than a single company):
22d72948	310	*
0a42beb6	311	* either:
7083f0fe	312	* project_component, event
0a42beb6	313	* or:
7083f0fe	314	* project, event
0a42beb6 MD	315	*
0a42beb6 MD	316	* Where "project" is the name of the project,
d5001b43 MD	317	* "component" is the name of the project component (which may
	318	* include several levels of sub-components, e.g.
	319	* ...component_subcomponent_...) where the tracepoint is located
	320	* (optional),
0a42beb6 MD	321	* "event" is the name of the tracepoint event.
	322	*
	323	* For projects issued from a single company wishing to advertise that
	324	* the company controls the source code and thus the tracepoints, the
	325	* "com_" prefix should be used:
	326	*
	327	* either:
7083f0fe	328	* com_company_project_component, event
0a42beb6	329	* or:
7083f0fe	330	* com_company_project, event
0a42beb6 MD	331	*
	332	* Where "company" is the name of the company,
	333	* "project" is the name of the project,
d5001b43 MD	334	* "component" is the name of the project component (which may
	335	* include several levels of sub-components, e.g.
	336	* ...component_subcomponent_...) where the tracepoint is located
	337	* (optional),
0a42beb6 MD	338	* "event" is the name of the tracepoint event.
0a42beb6 MD	339	*
b43de1e7	340	* the provider:event identifier is limited to 127 characters.
0a42beb6 MD	341	*
	342	* As an example, let's consider a user-space application "someproject"
	343	* that would have an internal thread scheduler:
	344	*
7083f0fe	345	* TRACEPOINT_EVENT(someproject_sched, switch,
22d72948 NC	346	*
22d72948 NC	347	* *
63ef2693 MD	348	* * Arguments to pass to the tracepoint. Supports from
63ef2693 MD	349	* * 0 to 10 "type, name" tuples.
22d72948 NC	350	* *
22d72948 NC	351	*
63ef2693 MD	352	* TP_ARGS(struct rq , rq, struct task_struct , prev,
63ef2693 MD	353	* struct task_struct *, next),
22d72948 NC	354	*
	355	* *
	356	* * Fast binary tracing: define the trace record via
81614639	357	* * TP_FIELDS(). You can think about it like a
22d72948 NC	358	* * regular C structure local variable definition.
	359	* *
	360	* * This is how the trace record is structured and will
	361	* * be saved into the ring buffer. These are the fields
	362	* * that will be exposed to readers.
	363	* *
0a42beb6	364	* * ctf_integer(pid_t, prev_pid, prev->pid) is equivalent
81614639	365	* * to a standard declaraton:
22d72948	366	* *
81614639	367	* * pid_t prev_pid;
22d72948	368	* *
81614639	369	* * followed by an assignment:
22d72948	370	* *
81614639	371	* * prev_pid = prev->pid;
22d72948	372	* *
0a42beb6	373	* * ctf_array(char, prev_comm, prev->comm, TASK_COMM_LEN) is
81614639	374	* * equivalent to:
22d72948	375	* *
81614639	376	* * char prev_comm[TASK_COMM_LEN];
22d72948	377	* *
81614639	378	* * followed by an assignment:
22d72948	379	* *
81614639	380	* * memcpy(prev_comm, prev->comm, TASK_COMM_LEN);
22d72948 NC	381	* *
22d72948 NC	382	*
81614639	383	* TP_FIELDS(
0a42beb6 MD	384	* ctf_array(char, prev_comm, prev->comm, TASK_COMM_LEN)
	385	* ctf_integer(pid_t, prev_pid, prev->pid)
	386	* ctf_integer(int, prev_prio, prev->prio)
	387	* ctf_array(char, next_comm, next->comm, TASK_COMM_LEN)
	388	* ctf_integer(pid_t, next_pid, next->pid)
	389	* ctf_integer(int, next_prio, next->prio)
22d72948	390	* )
0a42beb6	391	* )
abcdecad MD	392	*
	393	* Do _NOT_ add comma (,) nor semicolon (;) after the TRACEPOINT_EVENT
	394	* declaration.
	395	*
a4ada9b8	396	* The TRACEPOINT_PROVIDER must be defined when declaring a
abcdecad MD	397	* TRACEPOINT_EVENT. See ust/tracepoint-event.h for information about
abcdecad MD	398	* usage of other macros controlling TRACEPOINT_EVENT.
22d72948 NC	399	*/
22d72948 NC	400
63ef2693 MD	401	#define TRACEPOINT_EVENT(provider, name, args, fields) \
63ef2693 MD	402	_DECLARE_TRACEPOINT(provider, name, TP_PARAMS(args))
0c0686ee	403
63ef2693 MD	404	#define TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
	405	#define TRACEPOINT_EVENT_INSTANCE(provider, template, name, args)\
	406	_DECLARE_TRACEPOINT(provider, name, TP_PARAMS(args))
0c0686ee	407
81614639	408	#endif /* #ifndef TRACEPOINT_EVENT */
22d72948	409
abcdecad MD	410	#ifndef TRACEPOINT_LOGLEVEL
	411
	412	/*
	413	* Tracepoint Loglevel Declaration Facility
	414	*
	415	* This is a place-holder the tracepoint loglevel declaration,
	416	* overridden by the tracer implementation.
	417	*
	418	* Typical use of these loglevels:
	419	*
	420	* 1) Declare the mapping between loglevel names and an integer values
	421	* within TRACEPOINT_LOGLEVEL_ENUM, using TP_LOGLEVEL for each tuple.
	422	* Do _NOT_ add comma (,) nor semicolon (;) between the
	423	* TRACEPOINT_LOGLEVEL_ENUM entries. Do _NOT_ add comma (,) nor
	424	* semicolon (;) after the TRACEPOINT_LOGLEVEL_ENUM declaration. The
	425	* name should be a proper C99 identifier.
	426	*
	427	* TRACEPOINT_LOGLEVEL_ENUM(
	428	* TP_LOGLEVEL( < loglevel_name >, < value > )
	429	* TP_LOGLEVEL( < loglevel_name >, < value > )
	430	* ...
	431	* )
	432	*
	433	* e.g.:
	434	*
	435	* TRACEPOINT_LOGLEVEL_ENUM(
	436	* TP_LOGLEVEL(LOG_EMERG, 0)
	437	* TP_LOGLEVEL(LOG_ALERT, 1)
	438	* TP_LOGLEVEL(LOG_CRIT, 2)
	439	* TP_LOGLEVEL(LOG_ERR, 3)
	440	* TP_LOGLEVEL(LOG_WARNING, 4)
	441	* TP_LOGLEVEL(LOG_NOTICE, 5)
	442	* TP_LOGLEVEL(LOG_INFO, 6)
	443	* TP_LOGLEVEL(LOG_DEBUG, 7)
	444	* )
	445	*
e9f37b4c MD	446	* 2) Then, declare tracepoint loglevels for tracepoints. A
	447	* TRACEPOINT_EVENT should be declared prior to the the
	448	* TRACEPOINT_LOGLEVEL for a given tracepoint name. The first field
	449	* is the name of the tracepoint, the second field is the loglevel
	450	* name.
abcdecad	451	*
7083f0fe	452	* TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
abcdecad MD	453	* < loglevel_name >)
abcdecad MD	454	*
a4ada9b8	455	* The TRACEPOINT_PROVIDER must be defined when declaring a
abcdecad	456	* TRACEPOINT_LOGLEVEL_ENUM and TRACEPOINT_LOGLEVEL. The tracepoint
a4ada9b8	457	* loglevel enumeration apply to the entire TRACEPOINT_PROVIDER. Only one
abcdecad	458	* tracepoint loglevel enumeration should be declared per tracepoint
a4ada9b8	459	* provider.
abcdecad MD	460	*/
	461
	462	#define TRACEPOINT_LOGLEVEL_ENUM()
	463	#define TRACEPOINT_LOGLEVEL(name, loglevel)
	464
	465	#endif /* #ifndef TRACEPOINT_LOGLEVEL */