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

#ifndef _LINUX_TRACEPOINT_H
#define _LINUX_TRACEPOINT_H

/*
 * Copyright (C) 2008 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
 * Copyright (C) 2009 Pierre-Marc Fournier
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; 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.
 */

//#include <linux/immediate.h>
//#include <linux/types.h>
//#include <linux/rcupdate.h>

#include "immediate.h"
#include "kernelcompat.h"

struct module;
struct tracepoint;

struct tracepoint {
	const char *name;		/* Tracepoint name */
	DEFINE_IMV(char, state);	/* State. */
	void **funcs;
} __attribute__((aligned(32)));		/*
					 * Aligned on 32 bytes because it is
					 * globally visible and gcc happily
					 * align these on the structure size.
					 * Keep in sync with vmlinux.lds.h.
					 */

#define TPPROTO(args...)	args
#define TPARGS(args...)		args

//ust// #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 {								\
		void **it_func;						\
									\
		rcu_read_lock_sched_notrace();				\
		it_func = rcu_dereference((tp)->funcs);			\
		if (it_func) {						\
			do {						\
				((void(*)(proto))(*it_func))(args);	\
			} while (*(++it_func));				\
		}							\
		rcu_read_unlock_sched_notrace();			\
	} while (0)

#define __CHECK_TRACE(name, generic, proto, args)			\
	do {								\
		if (!generic) {						\
			if (unlikely(imv_read(__tracepoint_##name.state))) \
				__DO_TRACE(&__tracepoint_##name,	\
					TPPROTO(proto), TPARGS(args));	\
		} else {						\
			if (unlikely(_imv_read(__tracepoint_##name.state))) \
				__DO_TRACE(&__tracepoint_##name,	\
					TPPROTO(proto), TPARGS(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)				\
	extern struct tracepoint __tracepoint_##name;			\
	static inline void trace_##name(proto)				\
	{								\
		__CHECK_TRACE(name, 0, TPPROTO(proto), TPARGS(args));	\
	}								\
	static inline void _trace_##name(proto)				\
	{								\
		__CHECK_TRACE(name, 1, TPPROTO(proto), TPARGS(args));	\
	}								\
	static inline int register_trace_##name(void (*probe)(proto))	\
	{								\
		return tracepoint_probe_register(#name, (void *)probe);	\
	}								\
	static inline int unregister_trace_##name(void (*probe)(proto))	\
	{								\
		return tracepoint_probe_unregister(#name, (void *)probe);\
	}

#define DEFINE_TRACE(name)						\
	static const char __tpstrtab_##name[]				\
	__attribute__((section("__tracepoints_strings"))) = #name;	\
	struct tracepoint __tracepoint_##name				\
	__attribute__((section("__tracepoints"), aligned(32))) =	\
		{ __tpstrtab_##name, 0, NULL }

#define EXPORT_TRACEPOINT_SYMBOL_GPL(name)				\
	EXPORT_SYMBOL_GPL(__tracepoint_##name)
#define EXPORT_TRACEPOINT_SYMBOL(name)					\
	EXPORT_SYMBOL(__tracepoint_##name)

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

//ust// #else /* !CONFIG_TRACEPOINTS */
//ust// #define DECLARE_TRACE(name, proto, args)				\
//ust// 	static inline void trace_##name(proto)				\
//ust// 	{ }								\
//ust// 	static inline void _trace_##name(proto)				\
//ust// 	{ }								\
//ust// 	static inline int register_trace_##name(void (*probe)(proto))	\
//ust// 	{								\
//ust// 		return -ENOSYS;						\
//ust// 	}								\
//ust// 	static inline int unregister_trace_##name(void (*probe)(proto))	\
//ust// 	{								\
//ust// 		return -ENOSYS;						\
//ust// 	}
//ust// 
//ust// #define DEFINE_TRACE(name)
//ust// #define EXPORT_TRACEPOINT_SYMBOL_GPL(name)
//ust// #define EXPORT_TRACEPOINT_SYMBOL(name)
//ust// 
//ust// static inline void tracepoint_update_probe_range(struct tracepoint *begin,
//ust// 	struct tracepoint *end)
//ust// { }
//ust// #endif /* CONFIG_TRACEPOINTS */

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

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

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

struct tracepoint_iter {
//ust//	struct module *module;
	struct tracepoint_lib *lib;
	struct tracepoint *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 **tracepoint,
	struct tracepoint *begin, struct tracepoint *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)
{
	synchronize_sched();
}

struct tracepoint_lib {
	struct tracepoint *tracepoints_start;
	int tracepoints_count;
	struct list_head list;
};

#define TRACEPOINT_LIB									\
extern struct tracepoint __start___tracepoints[] __attribute__((visibility("hidden")));		\
extern struct tracepoint __stop___tracepoints[] __attribute__((visibility("hidden")));		\
											\
static void __attribute__((constructor)) __tracepoints__init(void) 				\
{											\
	tracepoint_register_lib(__start___tracepoints, (((long)__stop___tracepoints)-((long)__start___tracepoints))/sizeof(struct tracepoint));\
}
#endif
Commit	Line	Data
f99be407 PMF	1	#ifndef _LINUX_TRACEPOINT_H
	2	#define _LINUX_TRACEPOINT_H
	3
	4	/*
1f8b0dff PMF	5	* Copyright (C) 2008 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
1f8b0dff PMF	6	* Copyright (C) 2009 Pierre-Marc Fournier
f99be407	7	*
1f8b0dff PMF	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version 2
	11	* of the License, or (at your option) any later version.
f99be407	12	*
1f8b0dff PMF	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
f99be407 PMF	21	*
	22	* Heavily inspired from the Linux Kernel Markers.
	23	*
1f8b0dff	24	* Ported to userspace by Pierre-Marc Fournier.
f99be407 PMF	25	*/
f99be407 PMF	26
474d745f PMF	27	//#include <linux/immediate.h>
	28	//#include <linux/types.h>
	29	//#include <linux/rcupdate.h>
	30
	31	#include "immediate.h"
	32	#include "kernelcompat.h"
f99be407 PMF	33
	34	struct module;
	35	struct tracepoint;
	36
	37	struct tracepoint {
	38	const char name; / Tracepoint name */
	39	DEFINE_IMV(char, state); /* State. */
	40	void **funcs;
	41	} __attribute__((aligned(32))); /*
	42	* Aligned on 32 bytes because it is
	43	* globally visible and gcc happily
	44	* align these on the structure size.
	45	* Keep in sync with vmlinux.lds.h.
	46	*/
	47
	48	#define TPPROTO(args...) args
	49	#define TPARGS(args...) args
	50
474d745f	51	//ust// #ifdef CONFIG_TRACEPOINTS
f99be407 PMF	52
	53	/*
	54	* it_func[0] is never NULL because there is at least one element in the array
	55	* when the array itself is non NULL.
	56	*/
	57	#define __DO_TRACE(tp, proto, args) \
	58	do { \
	59	void **it_func; \
	60	\
	61	rcu_read_lock_sched_notrace(); \
	62	it_func = rcu_dereference((tp)->funcs); \
	63	if (it_func) { \
	64	do { \
	65	((void()(proto))(it_func))(args); \
	66	} while (*(++it_func)); \
	67	} \
	68	rcu_read_unlock_sched_notrace(); \
	69	} while (0)
	70
	71	#define __CHECK_TRACE(name, generic, proto, args) \
	72	do { \
	73	if (!generic) { \
	74	if (unlikely(imv_read(__tracepoint_##name.state))) \
	75	__DO_TRACE(&__tracepoint_##name, \
	76	TPPROTO(proto), TPARGS(args)); \
	77	} else { \
	78	if (unlikely(_imv_read(__tracepoint_##name.state))) \
	79	__DO_TRACE(&__tracepoint_##name, \
	80	TPPROTO(proto), TPARGS(args)); \
	81	} \
	82	} while (0)
	83
	84	/*
	85	* Make sure the alignment of the structure in the __tracepoints section will
	86	* not add unwanted padding between the beginning of the section and the
	87	* structure. Force alignment to the same alignment as the section start.
	88	*
	89	* The "generic" argument, passed to the declared __trace_##name inline
	90	* function controls which tracepoint enabling mechanism must be used.
	91	* If generic is true, a variable read is used.
	92	* If generic is false, immediate values are used.
	93	*/
	94	#define DECLARE_TRACE(name, proto, args) \
	95	extern struct tracepoint __tracepoint_##name; \
	96	static inline void trace_##name(proto) \
	97	{ \
	98	__CHECK_TRACE(name, 0, TPPROTO(proto), TPARGS(args)); \
	99	} \
	100	static inline void _trace_##name(proto) \
	101	{ \
	102	__CHECK_TRACE(name, 1, TPPROTO(proto), TPARGS(args)); \
	103	} \
	104	static inline int register_trace_##name(void (*probe)(proto)) \
	105	{ \
	106	return tracepoint_probe_register(#name, (void *)probe); \
	107	} \
	108	static inline int unregister_trace_##name(void (*probe)(proto)) \
	109	{ \
	110	return tracepoint_probe_unregister(#name, (void *)probe);\
	111	}
	112
	113	#define DEFINE_TRACE(name) \
	114	static const char __tpstrtab_##name[] \
	115	__attribute__((section("__tracepoints_strings"))) = #name; \
116	struct tracepoint __tracepoint_##name \
117	__attribute__((section("__tracepoints"), aligned(32))) = \
118	{ __tpstrtab_##name, 0, NULL }
119
120	#define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \
121	EXPORT_SYMBOL_GPL(__tracepoint_##name)
122	#define EXPORT_TRACEPOINT_SYMBOL(name) \
123	EXPORT_SYMBOL(__tracepoint_##name)
124
125	extern void tracepoint_update_probe_range(struct tracepoint *begin,
126	struct tracepoint *end);
127
474d745f PMF	128	//ust// #else /* !CONFIG_TRACEPOINTS */
	129	//ust// #define DECLARE_TRACE(name, proto, args) \
	130	//ust// static inline void trace_##name(proto) \
	131	//ust// { } \
	132	//ust// static inline void _trace_##name(proto) \
	133	//ust// { } \
	134	//ust// static inline int register_trace_##name(void (*probe)(proto)) \
	135	//ust// { \
	136	//ust// return -ENOSYS; \
	137	//ust// } \
	138	//ust// static inline int unregister_trace_##name(void (*probe)(proto)) \
	139	//ust// { \
	140	//ust// return -ENOSYS; \
	141	//ust// }
	142	//ust//
	143	//ust// #define DEFINE_TRACE(name)
	144	//ust// #define EXPORT_TRACEPOINT_SYMBOL_GPL(name)
	145	//ust// #define EXPORT_TRACEPOINT_SYMBOL(name)
	146	//ust//
	147	//ust// static inline void tracepoint_update_probe_range(struct tracepoint *begin,
	148	//ust// struct tracepoint *end)
	149	//ust// { }
	150	//ust// #endif /* CONFIG_TRACEPOINTS */
f99be407 PMF	151
	152	/*
	153	* Connect a probe to a tracepoint.
	154	* Internal API, should not be used directly.
	155	*/
	156	extern int tracepoint_probe_register(const char name, void probe);
	157
	158	/*
	159	* Disconnect a probe from a tracepoint.
	160	* Internal API, should not be used directly.
	161	*/
	162	extern int tracepoint_probe_unregister(const char name, void probe);
	163
	164	extern int tracepoint_probe_register_noupdate(const char name, void probe);
	165	extern int tracepoint_probe_unregister_noupdate(const char name, void probe);
	166	extern void tracepoint_probe_update_all(void);
	167
	168	struct tracepoint_iter {
474d745f PMF	169	//ust// struct module *module;
474d745f PMF	170	struct tracepoint_lib *lib;
f99be407 PMF	171	struct tracepoint *tracepoint;
	172	};
	173
	174	extern void tracepoint_iter_start(struct tracepoint_iter *iter);
	175	extern void tracepoint_iter_next(struct tracepoint_iter *iter);
	176	extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
	177	extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
	178	extern int tracepoint_get_iter_range(struct tracepoint **tracepoint,
	179	struct tracepoint begin, struct tracepoint end);
	180
	181	/*
	182	* tracepoint_synchronize_unregister must be called between the last tracepoint
	183	* probe unregistration and the end of module exit to make sure there is no
	184	* caller executing a probe when it is freed.
	185	*/
	186	static inline void tracepoint_synchronize_unregister(void)
	187	{
	188	synchronize_sched();
	189	}
	190
474d745f PMF	191	struct tracepoint_lib {
	192	struct tracepoint *tracepoints_start;
	193	int tracepoints_count;
	194	struct list_head list;
	195	};
	196
	197	#define TRACEPOINT_LIB \
	198	extern struct tracepoint __start___tracepoints[] __attribute__((visibility("hidden"))); \
	199	extern struct tracepoint __stop___tracepoints[] __attribute__((visibility("hidden"))); \
	200	\
	201	static void __attribute__((constructor)) __tracepoints__init(void) \
	202	{ \
	203	tracepoint_register_lib(__start___tracepoints, (((long)__stop___tracepoints)-((long)__start___tracepoints))/sizeof(struct tracepoint));\
	204	}
f99be407	205	#endif