[ceph.git] / ceph / src / spdk / include / spdk / trace.h

/*-
 *   BSD LICENSE
 *
 *   Copyright (c) Intel Corporation.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * \file
 * Tracepoint library
 */

#ifndef _SPDK_TRACE_H_
#define _SPDK_TRACE_H_

#include "spdk/stdinc.h"

#ifdef __cplusplus
extern "C" {
#endif

#define SPDK_TRACE_SIZE	 (32 * 1024)

struct spdk_trace_entry {
	uint64_t	tsc;
	uint16_t	tpoint_id;
	uint16_t	poller_id;
	uint32_t	size;
	uint64_t	object_id;
	uint64_t	arg1;
};

/* If type changes from a uint8_t, change this value. */
#define SPDK_TRACE_MAX_OWNER (UCHAR_MAX + 1)

struct spdk_trace_owner {
	uint8_t	type;
	char	id_prefix;
};

/* If type changes from a uint8_t, change this value. */
#define SPDK_TRACE_MAX_OBJECT (UCHAR_MAX + 1)

struct spdk_trace_object {
	uint8_t	type;
	char	id_prefix;
};

#define SPDK_TRACE_MAX_GROUP_ID  16
#define SPDK_TRACE_MAX_TPOINT_ID (SPDK_TRACE_MAX_GROUP_ID * 64)
#define SPDK_TPOINT_ID(group, tpoint)	((group * 64) + tpoint)

struct spdk_trace_tpoint {
	char		name[44];
	char		short_name[4];
	uint16_t	tpoint_id;
	uint8_t		owner_type;
	uint8_t		object_type;
	uint8_t		new_object;
	uint8_t		arg1_is_ptr;
	uint8_t		reserved;
	char		arg1_name[8];
};

struct spdk_trace_history {
	/** Logical core number associated with this structure instance. */
	int				lcore;

	/**
	 * Circular buffer of spdk_trace_entry structures for tracing
	 *  tpoints on this core.  Debug tool spdk_trace reads this
	 *  buffer from shared memory to post-process the tpoint entries and
	 *  display in a human-readable format.
	 */
	struct spdk_trace_entry		entries[SPDK_TRACE_SIZE];

	/**
	 * Running count of number of occurrences of each tracepoint on this
	 *  lcore.  Debug tools can use this to easily count tracepoints such as
	 *  number of SCSI tasks completed or PDUs read.
	 */
	uint64_t			tpoint_count[SPDK_TRACE_MAX_TPOINT_ID];

	/** Index to next spdk_trace_entry to fill in the circular buffer. */
	uint32_t			next_entry;

};

#define SPDK_TRACE_MAX_LCORE		128

struct spdk_trace_flags {
	uint64_t			tsc_rate;
	uint64_t			tpoint_mask[SPDK_TRACE_MAX_GROUP_ID];
	struct spdk_trace_owner		owner[UCHAR_MAX + 1];
	struct spdk_trace_object	object[UCHAR_MAX + 1];
	struct spdk_trace_tpoint	tpoint[SPDK_TRACE_MAX_TPOINT_ID];
};
extern struct spdk_trace_flags *g_trace_flags;
extern struct spdk_trace_histories *g_trace_histories;


struct spdk_trace_histories {
	struct spdk_trace_flags flags;
	struct spdk_trace_history	per_lcore_history[SPDK_TRACE_MAX_LCORE];
};

void _spdk_trace_record(uint64_t tsc, uint16_t tpoint_id, uint16_t poller_id,
			uint32_t size, uint64_t object_id, uint64_t arg1);

/**
 * Record the current trace state for tracing tpoints. Debug tool can read the
 * information from shared memory to post-process the tpoint entries and display
 * in a human-readable format. This function will call spdk_get_ticks() to get
 * the current tsc to save in the tracepoint.
 *
 * \param tpoint_id Tracepoint id to record.
 * \param poller_id Poller id to record.
 * \param size Size to record.
 * \param object_id Object id to record.
 * \param arg1 Argument to record.
 */
static inline
void spdk_trace_record(uint16_t tpoint_id, uint16_t poller_id, uint32_t size,
		       uint64_t object_id, uint64_t arg1)
{
	/*
	 * Tracepoint group ID is encoded in the tpoint_id.  Lower 6 bits determine the tracepoint
	 *  within the group, the remaining upper bits determine the tracepoint group.  Each
	 *  tracepoint group has its own tracepoint mask.
	 */
	if (g_trace_histories == NULL ||
	    !((1ULL << (tpoint_id & 0x3F)) & g_trace_histories->flags.tpoint_mask[tpoint_id >> 6])) {
		return;
	}

	_spdk_trace_record(0, tpoint_id, poller_id, size, object_id, arg1);
}

/**
 * Record the current trace state for tracing tpoints. Debug tool can read the
 * information from shared memory to post-process the tpoint entries and display
 * in a human-readable format.
 *
 * \param tsc Current tsc.
 * \param tpoint_id Tracepoint id to record.
 * \param poller_id Poller id to record.
 * \param size Size to record.
 * \param object_id Object id to record.
 * \param arg1 Argument to record.
 */
static inline
void spdk_trace_record_tsc(uint64_t tsc, uint16_t tpoint_id, uint16_t poller_id,
			   uint32_t size, uint64_t object_id, uint64_t arg1)
{
	/*
	 * Tracepoint group ID is encoded in the tpoint_id.  Lower 6 bits determine the tracepoint
	 *  within the group, the remaining upper bits determine the tracepoint group.  Each
	 *  tracepoint group has its own tracepoint mask.
	 */
	if (g_trace_histories == NULL ||
	    !((1ULL << (tpoint_id & 0x3F)) & g_trace_histories->flags.tpoint_mask[tpoint_id >> 6])) {
		return;
	}

	_spdk_trace_record(tsc, tpoint_id, poller_id, size, object_id, arg1);
}

/**
 * Get the current tpoint mask of the given tpoint group.
 *
 * \param group_id Tpoint group id associated with the tpoint mask.
 *
 * \return current tpoint mask.
 */
uint64_t spdk_trace_get_tpoint_mask(uint32_t group_id);

/**
 * Add the specified tpoints to the current tpoint mask for the given tpoint group.
 *
 * \param group_id Tpoint group id associated with the tpoint mask.
 * \param tpoint_mask Tpoint mask which indicates which tpoints to add to the
 * current tpoint mask.
 */
void spdk_trace_set_tpoints(uint32_t group_id, uint64_t tpoint_mask);

/**
 * Clear the specified tpoints from the current tpoint mask for the given tpoint group.
 *
 * \param group_id Tpoint group id associated with the tpoint mask.
 * \param tpoint_mask Tpoint mask which indicates which tpoints to clear from
 * the current tpoint mask.
 */
void spdk_trace_clear_tpoints(uint32_t group_id, uint64_t tpoint_mask);

/**
 * Get a mask of all tracepoint groups which have at least one tracepoint enabled.
 *
 * \return a mask of all tracepoint groups.
 */
uint64_t spdk_trace_get_tpoint_group_mask(void);

/**
 * For each tpoint group specified in the group mask, enable all of its tpoints.
 *
 * \param tpoint_group_mask Tpoint group mask that indicates which tpoints to enable.
 */
void spdk_trace_set_tpoint_group_mask(uint64_t tpoint_group_mask);

/**
 * Initialize the trace environment. Debug tool can read the information from
 * the given shared memory to post-process the tpoint entries and display in a
 * human-readable format.
 *
 * \param shm_name Name of shared memory.
 * \return 0 on success, else non-zero indicates a failure.
 */
int spdk_trace_init(const char *shm_name);

/**
 * Unmap global trace memory structs.
 */
void spdk_trace_cleanup(void);

/**
 * Initialize trace flags.
 */
void spdk_trace_flags_init(void);

#define OWNER_NONE 0
#define OBJECT_NONE 0

/**
 * Register the trace owner.
 *
 * \param type Type of the trace owner.
 * \param id_prefix Prefix of id for the trace owner.
 */
void spdk_trace_register_owner(uint8_t type, char id_prefix);

/**
 * Register the trace object.
 *
 * \param type Type of the trace object.
 * \param id_prefix Prefix of id for the trace object.
 */
void spdk_trace_register_object(uint8_t type, char id_prefix);

/**
 * Register the description for the tpoint.
 *
 * \param name Name for the tpoint.
 * \param short_name Short name for the tpoint.
 * \param tpoint_id Id for the tpoint.
 * \param owner_type Owner type for the tpoint.
 * \param object_type Object type for the tpoint.
 * \param new_object New object for the tpoint.
 * \param arg1_is_ptr This argument indicates whether argument1 is a pointer.
 * \param arg1_name Name of argument.
 */
void spdk_trace_register_description(const char *name, const char *short_name,
				     uint16_t tpoint_id, uint8_t owner_type,
				     uint8_t object_type, uint8_t new_object,
				     uint8_t arg1_is_ptr, const char *arg1_name);

struct spdk_trace_register_fn {
	void (*reg_fn)(void);
	struct spdk_trace_register_fn *next;
};

/**
 * Add new trace register function.
 *
 * \param reg_fn Trace register function to add.
 */
void spdk_trace_add_register_fn(struct spdk_trace_register_fn *reg_fn);

#define SPDK_TRACE_REGISTER_FN(fn)				\
	static void fn(void);					\
	struct spdk_trace_register_fn reg_ ## fn = {		\
		.reg_fn = fn,					\
		.next = NULL,					\
	};							\
	__attribute__((constructor)) static void _ ## fn(void)	\
	{							\
		spdk_trace_add_register_fn(&reg_ ## fn);	\
	}							\
	static void fn(void)

#ifdef __cplusplus
}
#endif

#endif
Commit	Line	Data
7c673cae FG	1	/*-
	2	* BSD LICENSE
	3	*
	4	* Copyright (c) Intel Corporation.
	5	* All rights reserved.
	6	*
	7	* Redistribution and use in source and binary forms, with or without
	8	* modification, are permitted provided that the following conditions
	9	* are met:
	10	*
	11	* * Redistributions of source code must retain the above copyright
	12	* notice, this list of conditions and the following disclaimer.
	13	* * Redistributions in binary form must reproduce the above copyright
	14	* notice, this list of conditions and the following disclaimer in
	15	* the documentation and/or other materials provided with the
	16	* distribution.
	17	* * Neither the name of Intel Corporation nor the names of its
	18	* contributors may be used to endorse or promote products derived
	19	* from this software without specific prior written permission.
	20	*
	21	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	22	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	23	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	24	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	25	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	26	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	27	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	28	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	29	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	30	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	31	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	32	*/
	33
	34	/**
	35	* \file
	36	* Tracepoint library
	37	*/
	38
	39	#ifndef _SPDK_TRACE_H_
	40	#define _SPDK_TRACE_H_
	41
11fdf7f2	42	#include "spdk/stdinc.h"
7c673cae FG	43
	44	#ifdef __cplusplus
	45	extern "C" {
	46	#endif
	47
	48	#define SPDK_TRACE_SIZE (32 * 1024)
	49
	50	struct spdk_trace_entry {
	51	uint64_t tsc;
	52	uint16_t tpoint_id;
	53	uint16_t poller_id;
	54	uint32_t size;
	55	uint64_t object_id;
	56	uint64_t arg1;
	57	};
	58
	59	/* If type changes from a uint8_t, change this value. */
	60	#define SPDK_TRACE_MAX_OWNER (UCHAR_MAX + 1)
	61
	62	struct spdk_trace_owner {
	63	uint8_t type;
	64	char id_prefix;
	65	};
	66
	67	/* If type changes from a uint8_t, change this value. */
	68	#define SPDK_TRACE_MAX_OBJECT (UCHAR_MAX + 1)
	69
	70	struct spdk_trace_object {
	71	uint8_t type;
	72	char id_prefix;
	73	};
	74
	75	#define SPDK_TRACE_MAX_GROUP_ID 16
	76	#define SPDK_TRACE_MAX_TPOINT_ID (SPDK_TRACE_MAX_GROUP_ID * 64)
	77	#define SPDK_TPOINT_ID(group, tpoint) ((group * 64) + tpoint)
	78
	79	struct spdk_trace_tpoint {
	80	char name[44];
	81	char short_name[4];
	82	uint16_t tpoint_id;
	83	uint8_t owner_type;
	84	uint8_t object_type;
	85	uint8_t new_object;
	86	uint8_t arg1_is_ptr;
11fdf7f2	87	uint8_t reserved;
7c673cae FG	88	char arg1_name[8];
	89	};
	90
	91	struct spdk_trace_history {
	92	/** Logical core number associated with this structure instance. */
	93	int lcore;
	94
	95	/**
	96	* Circular buffer of spdk_trace_entry structures for tracing
	97	* tpoints on this core. Debug tool spdk_trace reads this
	98	* buffer from shared memory to post-process the tpoint entries and
	99	* display in a human-readable format.
	100	*/
	101	struct spdk_trace_entry entries[SPDK_TRACE_SIZE];
	102
	103	/**
	104	* Running count of number of occurrences of each tracepoint on this
	105	* lcore. Debug tools can use this to easily count tracepoints such as
	106	* number of SCSI tasks completed or PDUs read.
	107	*/
	108	uint64_t tpoint_count[SPDK_TRACE_MAX_TPOINT_ID];
	109
	110	/** Index to next spdk_trace_entry to fill in the circular buffer. */
	111	uint32_t next_entry;
	112
	113	};
	114
	115	#define SPDK_TRACE_MAX_LCORE 128
	116
11fdf7f2	117	struct spdk_trace_flags {
7c673cae FG	118	uint64_t tsc_rate;
7c673cae FG	119	uint64_t tpoint_mask[SPDK_TRACE_MAX_GROUP_ID];
7c673cae FG	120	struct spdk_trace_owner owner[UCHAR_MAX + 1];
	121	struct spdk_trace_object object[UCHAR_MAX + 1];
	122	struct spdk_trace_tpoint tpoint[SPDK_TRACE_MAX_TPOINT_ID];
	123	};
11fdf7f2 TL	124	extern struct spdk_trace_flags *g_trace_flags;
	125	extern struct spdk_trace_histories *g_trace_histories;
	126
	127
	128	struct spdk_trace_histories {
	129	struct spdk_trace_flags flags;
	130	struct spdk_trace_history per_lcore_history[SPDK_TRACE_MAX_LCORE];
	131	};
7c673cae	132
11fdf7f2 TL	133	void _spdk_trace_record(uint64_t tsc, uint16_t tpoint_id, uint16_t poller_id,
11fdf7f2 TL	134	uint32_t size, uint64_t object_id, uint64_t arg1);
7c673cae	135
11fdf7f2 TL	136	/**
	137	* Record the current trace state for tracing tpoints. Debug tool can read the
	138	* information from shared memory to post-process the tpoint entries and display
	139	* in a human-readable format. This function will call spdk_get_ticks() to get
	140	* the current tsc to save in the tracepoint.
	141	*
	142	* \param tpoint_id Tracepoint id to record.
	143	* \param poller_id Poller id to record.
	144	* \param size Size to record.
	145	* \param object_id Object id to record.
	146	* \param arg1 Argument to record.
	147	*/
	148	static inline
7c673cae	149	void spdk_trace_record(uint16_t tpoint_id, uint16_t poller_id, uint32_t size,
11fdf7f2 TL	150	uint64_t object_id, uint64_t arg1)
	151	{
	152	/*
	153	* Tracepoint group ID is encoded in the tpoint_id. Lower 6 bits determine the tracepoint
	154	* within the group, the remaining upper bits determine the tracepoint group. Each
	155	* tracepoint group has its own tracepoint mask.
	156	*/
	157	if (g_trace_histories == NULL \|\|
	158	!((1ULL << (tpoint_id & 0x3F)) & g_trace_histories->flags.tpoint_mask[tpoint_id >> 6])) {
	159	return;
	160	}
	161
	162	_spdk_trace_record(0, tpoint_id, poller_id, size, object_id, arg1);
	163	}
	164
	165	/**
	166	* Record the current trace state for tracing tpoints. Debug tool can read the
	167	* information from shared memory to post-process the tpoint entries and display
	168	* in a human-readable format.
	169	*
	170	* \param tsc Current tsc.
	171	* \param tpoint_id Tracepoint id to record.
	172	* \param poller_id Poller id to record.
	173	* \param size Size to record.
	174	* \param object_id Object id to record.
	175	* \param arg1 Argument to record.
	176	*/
	177	static inline
	178	void spdk_trace_record_tsc(uint64_t tsc, uint16_t tpoint_id, uint16_t poller_id,
	179	uint32_t size, uint64_t object_id, uint64_t arg1)
	180	{
	181	/*
	182	* Tracepoint group ID is encoded in the tpoint_id. Lower 6 bits determine the tracepoint
	183	* within the group, the remaining upper bits determine the tracepoint group. Each
	184	* tracepoint group has its own tracepoint mask.
	185	*/
	186	if (g_trace_histories == NULL \|\|
	187	!((1ULL << (tpoint_id & 0x3F)) & g_trace_histories->flags.tpoint_mask[tpoint_id >> 6])) {
	188	return;
	189	}
	190
	191	_spdk_trace_record(tsc, tpoint_id, poller_id, size, object_id, arg1);
	192	}
7c673cae	193
11fdf7f2 TL	194	/**
	195	* Get the current tpoint mask of the given tpoint group.
	196	*
	197	* \param group_id Tpoint group id associated with the tpoint mask.
	198	*
	199	* \return current tpoint mask.
	200	*/
7c673cae FG	201	uint64_t spdk_trace_get_tpoint_mask(uint32_t group_id);
7c673cae FG	202
11fdf7f2 TL	203	/**
	204	* Add the specified tpoints to the current tpoint mask for the given tpoint group.
	205	*
	206	* \param group_id Tpoint group id associated with the tpoint mask.
	207	* \param tpoint_mask Tpoint mask which indicates which tpoints to add to the
	208	* current tpoint mask.
	209	*/
7c673cae FG	210	void spdk_trace_set_tpoints(uint32_t group_id, uint64_t tpoint_mask);
7c673cae FG	211
11fdf7f2 TL	212	/**
	213	* Clear the specified tpoints from the current tpoint mask for the given tpoint group.
	214	*
	215	* \param group_id Tpoint group id associated with the tpoint mask.
	216	* \param tpoint_mask Tpoint mask which indicates which tpoints to clear from
	217	* the current tpoint mask.
	218	*/
7c673cae FG	219	void spdk_trace_clear_tpoints(uint32_t group_id, uint64_t tpoint_mask);
7c673cae FG	220
11fdf7f2 TL	221	/**
	222	* Get a mask of all tracepoint groups which have at least one tracepoint enabled.
	223	*
	224	* \return a mask of all tracepoint groups.
	225	*/
7c673cae FG	226	uint64_t spdk_trace_get_tpoint_group_mask(void);
7c673cae FG	227
11fdf7f2 TL	228	/**
	229	* For each tpoint group specified in the group mask, enable all of its tpoints.
	230	*
	231	* \param tpoint_group_mask Tpoint group mask that indicates which tpoints to enable.
	232	*/
7c673cae FG	233	void spdk_trace_set_tpoint_group_mask(uint64_t tpoint_group_mask);
7c673cae FG	234
11fdf7f2 TL	235	/**
	236	* Initialize the trace environment. Debug tool can read the information from
	237	* the given shared memory to post-process the tpoint entries and display in a
	238	* human-readable format.
	239	*
	240	* \param shm_name Name of shared memory.
	241	* \return 0 on success, else non-zero indicates a failure.
	242	*/
	243	int spdk_trace_init(const char *shm_name);
	244
	245	/**
	246	* Unmap global trace memory structs.
	247	*/
7c673cae FG	248	void spdk_trace_cleanup(void);
7c673cae FG	249
11fdf7f2 TL	250	/**
	251	* Initialize trace flags.
	252	*/
	253	void spdk_trace_flags_init(void);
	254
7c673cae FG	255	#define OWNER_NONE 0
	256	#define OBJECT_NONE 0
	257
11fdf7f2 TL	258	/**
	259	* Register the trace owner.
	260	*
	261	* \param type Type of the trace owner.
	262	* \param id_prefix Prefix of id for the trace owner.
	263	*/
7c673cae	264	void spdk_trace_register_owner(uint8_t type, char id_prefix);
11fdf7f2 TL	265
	266	/**
	267	* Register the trace object.
	268	*
	269	* \param type Type of the trace object.
	270	* \param id_prefix Prefix of id for the trace object.
	271	*/
7c673cae	272	void spdk_trace_register_object(uint8_t type, char id_prefix);
11fdf7f2 TL	273
	274	/**
	275	* Register the description for the tpoint.
	276	*
	277	* \param name Name for the tpoint.
	278	* \param short_name Short name for the tpoint.
	279	* \param tpoint_id Id for the tpoint.
	280	* \param owner_type Owner type for the tpoint.
	281	* \param object_type Object type for the tpoint.
	282	* \param new_object New object for the tpoint.
	283	* \param arg1_is_ptr This argument indicates whether argument1 is a pointer.
	284	* \param arg1_name Name of argument.
	285	*/
7c673cae FG	286	void spdk_trace_register_description(const char name, const char short_name,
	287	uint16_t tpoint_id, uint8_t owner_type,
	288	uint8_t object_type, uint8_t new_object,
11fdf7f2	289	uint8_t arg1_is_ptr, const char *arg1_name);
7c673cae FG	290
	291	struct spdk_trace_register_fn {
	292	void (*reg_fn)(void);
	293	struct spdk_trace_register_fn *next;
	294	};
	295
11fdf7f2 TL	296	/**
	297	* Add new trace register function.
	298	*
	299	* \param reg_fn Trace register function to add.
	300	*/
7c673cae FG	301	void spdk_trace_add_register_fn(struct spdk_trace_register_fn *reg_fn);
7c673cae FG	302
11fdf7f2	303	#define SPDK_TRACE_REGISTER_FN(fn) \
7c673cae FG	304	static void fn(void); \
	305	struct spdk_trace_register_fn reg_ ## fn = { \
	306	.reg_fn = fn, \
	307	.next = NULL, \
	308	}; \
	309	__attribute__((constructor)) static void _ ## fn(void) \
	310	{ \
	311	spdk_trace_add_register_fn(&reg_ ## fn); \
	312	} \
	313	static void fn(void)
	314
	315	#ifdef __cplusplus
	316	}
	317	#endif
	318
	319	#endif