[lttng-ust.git] / libust / 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 "urcu.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(); /*ust 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(); /*ust 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
769d0157	31	//#include "urcu.h"
474d745f PMF	32	#include "immediate.h"
474d745f PMF	33	#include "kernelcompat.h"
f99be407 PMF	34
	35	struct module;
	36	struct tracepoint;
	37
	38	struct tracepoint {
	39	const char name; / Tracepoint name */
	40	DEFINE_IMV(char, state); /* State. */
	41	void **funcs;
	42	} __attribute__((aligned(32))); /*
	43	* Aligned on 32 bytes because it is
	44	* globally visible and gcc happily
	45	* align these on the structure size.
	46	* Keep in sync with vmlinux.lds.h.
	47	*/
	48
	49	#define TPPROTO(args...) args
	50	#define TPARGS(args...) args
	51
474d745f	52	//ust// #ifdef CONFIG_TRACEPOINTS
f99be407 PMF	53
	54	/*
	55	* it_func[0] is never NULL because there is at least one element in the array
	56	* when the array itself is non NULL.
	57	*/
	58	#define __DO_TRACE(tp, proto, args) \
	59	do { \
	60	void **it_func; \
	61	\
6cb88bc0	62	rcu_read_lock(); /ust rcu_read_lock_sched_notrace(); / \
f99be407 PMF	63	it_func = rcu_dereference((tp)->funcs); \
	64	if (it_func) { \
	65	do { \
	66	((void()(proto))(it_func))(args); \
	67	} while (*(++it_func)); \
	68	} \
6cb88bc0	69	rcu_read_unlock(); /ust rcu_read_unlock_sched_notrace(); / \
f99be407 PMF	70	} while (0)
	71
	72	#define __CHECK_TRACE(name, generic, proto, args) \
	73	do { \
	74	if (!generic) { \
	75	if (unlikely(imv_read(__tracepoint_##name.state))) \
	76	__DO_TRACE(&__tracepoint_##name, \
	77	TPPROTO(proto), TPARGS(args)); \
	78	} else { \
	79	if (unlikely(_imv_read(__tracepoint_##name.state))) \
	80	__DO_TRACE(&__tracepoint_##name, \
	81	TPPROTO(proto), TPARGS(args)); \
	82	} \
	83	} while (0)
	84
	85	/*
	86	* Make sure the alignment of the structure in the __tracepoints section will
	87	* not add unwanted padding between the beginning of the section and the
	88	* structure. Force alignment to the same alignment as the section start.
	89	*
	90	* The "generic" argument, passed to the declared __trace_##name inline
	91	* function controls which tracepoint enabling mechanism must be used.
	92	* If generic is true, a variable read is used.
	93	* If generic is false, immediate values are used.
	94	*/
	95	#define DECLARE_TRACE(name, proto, args) \
	96	extern struct tracepoint __tracepoint_##name; \
	97	static inline void trace_##name(proto) \
	98	{ \
	99	__CHECK_TRACE(name, 0, TPPROTO(proto), TPARGS(args)); \
	100	} \
	101	static inline void _trace_##name(proto) \
	102	{ \
	103	__CHECK_TRACE(name, 1, TPPROTO(proto), TPARGS(args)); \
	104	} \
	105	static inline int register_trace_##name(void (*probe)(proto)) \
	106	{ \
	107	return tracepoint_probe_register(#name, (void *)probe); \
	108	} \
	109	static inline int unregister_trace_##name(void (*probe)(proto)) \
	110	{ \
	111	return tracepoint_probe_unregister(#name, (void *)probe);\
	112	}
	113
	114	#define DEFINE_TRACE(name) \
	115	static const char __tpstrtab_##name[] \
	116	__attribute__((section("__tracepoints_strings"))) = #name; \
	117	struct tracepoint __tracepoint_##name \
	118	__attribute__((section("__tracepoints"), aligned(32))) = \
	119	{ __tpstrtab_##name, 0, NULL }
	120
	121	#define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \
	122	EXPORT_SYMBOL_GPL(__tracepoint_##name)
	123	#define EXPORT_TRACEPOINT_SYMBOL(name) \
	124	EXPORT_SYMBOL(__tracepoint_##name)
	125
	126	extern void tracepoint_update_probe_range(struct tracepoint *begin,
	127	struct tracepoint *end);
	128
474d745f PMF	129	//ust// #else /* !CONFIG_TRACEPOINTS */
	130	//ust// #define DECLARE_TRACE(name, proto, args) \
	131	//ust// static inline void trace_##name(proto) \
	132	//ust// { } \
	133	//ust// static inline void _trace_##name(proto) \
	134	//ust// { } \
	135	//ust// static inline int register_trace_##name(void (*probe)(proto)) \
	136	//ust// { \
	137	//ust// return -ENOSYS; \
	138	//ust// } \
	139	//ust// static inline int unregister_trace_##name(void (*probe)(proto)) \
	140	//ust// { \
	141	//ust// return -ENOSYS; \
	142	//ust// }
	143	//ust//
	144	//ust// #define DEFINE_TRACE(name)
	145	//ust// #define EXPORT_TRACEPOINT_SYMBOL_GPL(name)
	146	//ust// #define EXPORT_TRACEPOINT_SYMBOL(name)
	147	//ust//
	148	//ust// static inline void tracepoint_update_probe_range(struct tracepoint *begin,
	149	//ust// struct tracepoint *end)
	150	//ust// { }
	151	//ust// #endif /* CONFIG_TRACEPOINTS */
f99be407 PMF	152
	153	/*
	154	* Connect a probe to a tracepoint.
	155	* Internal API, should not be used directly.
	156	*/
	157	extern int tracepoint_probe_register(const char name, void probe);
	158
	159	/*
	160	* Disconnect a probe from a tracepoint.
	161	* Internal API, should not be used directly.
	162	*/
	163	extern int tracepoint_probe_unregister(const char name, void probe);
	164
	165	extern int tracepoint_probe_register_noupdate(const char name, void probe);
	166	extern int tracepoint_probe_unregister_noupdate(const char name, void probe);
	167	extern void tracepoint_probe_update_all(void);
	168
	169	struct tracepoint_iter {
474d745f PMF	170	//ust// struct module *module;
474d745f PMF	171	struct tracepoint_lib *lib;
f99be407 PMF	172	struct tracepoint *tracepoint;
	173	};
	174
	175	extern void tracepoint_iter_start(struct tracepoint_iter *iter);
	176	extern void tracepoint_iter_next(struct tracepoint_iter *iter);
	177	extern void tracepoint_iter_stop(struct tracepoint_iter *iter);
	178	extern void tracepoint_iter_reset(struct tracepoint_iter *iter);
	179	extern int tracepoint_get_iter_range(struct tracepoint **tracepoint,
	180	struct tracepoint begin, struct tracepoint end);
	181
	182	/*
	183	* tracepoint_synchronize_unregister must be called between the last tracepoint
	184	* probe unregistration and the end of module exit to make sure there is no
	185	* caller executing a probe when it is freed.
	186	*/
	187	static inline void tracepoint_synchronize_unregister(void)
	188	{
	189	synchronize_sched();
	190	}
	191
474d745f PMF	192	struct tracepoint_lib {
	193	struct tracepoint *tracepoints_start;
	194	int tracepoints_count;
	195	struct list_head list;
	196	};
	197
	198	#define TRACEPOINT_LIB \
	199	extern struct tracepoint __start___tracepoints[] __attribute__((visibility("hidden"))); \
	200	extern struct tracepoint __stop___tracepoints[] __attribute__((visibility("hidden"))); \
	201	\
	202	static void __attribute__((constructor)) __tracepoints__init(void) \
	203	{ \
	204	tracepoint_register_lib(__start___tracepoints, (((long)__stop___tracepoints)-((long)__start___tracepoints))/sizeof(struct tracepoint));\
	205	}
f99be407	206	#endif