[lttng-modules.git] / lib / ringbuffer / config.h

#ifndef _LIB_RING_BUFFER_CONFIG_H
#define _LIB_RING_BUFFER_CONFIG_H

/*
 * lib/ringbuffer/config.h
 *
 * Ring buffer configuration header. Note: after declaring the standard inline
 * functions, clients should also include linux/ringbuffer/api.h.
 *
 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * 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; only
 * 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
 */

#include <linux/types.h>
#include <linux/percpu.h>
#include <lib/align.h>
#include <lttng-tracer-core.h>

struct lib_ring_buffer;
struct channel;
struct lib_ring_buffer_config;
struct lib_ring_buffer_ctx;

/*
 * Ring buffer client callbacks. Only used by slow path, never on fast path.
 * For the fast path, record_header_size(), ring_buffer_clock_read() should be
 * provided as inline functions too.  These may simply return 0 if not used by
 * the client.
 */
struct lib_ring_buffer_client_cb {
	/* Mandatory callbacks */

	/* A static inline version is also required for fast path */
	u64 (*ring_buffer_clock_read) (struct channel *chan);
	size_t (*record_header_size) (const struct lib_ring_buffer_config *config,
				      struct channel *chan, size_t offset,
				      size_t *pre_header_padding,
				      struct lib_ring_buffer_ctx *ctx,
				      void *client_ctx);

	/* Slow path only, at subbuffer switch */
	size_t (*subbuffer_header_size) (void);
	void (*buffer_begin) (struct lib_ring_buffer *buf, u64 tsc,
			      unsigned int subbuf_idx);
	void (*buffer_end) (struct lib_ring_buffer *buf, u64 tsc,
			    unsigned int subbuf_idx, unsigned long data_size);

	/* Optional callbacks (can be set to NULL) */

	/* Called at buffer creation/finalize */
	int (*buffer_create) (struct lib_ring_buffer *buf, void *priv,
			      int cpu, const char *name);
	/*
	 * Clients should guarantee that no new reader handle can be opened
	 * after finalize.
	 */
	void (*buffer_finalize) (struct lib_ring_buffer *buf, void *priv, int cpu);

	/*
	 * Extract header length, payload length and timestamp from event
	 * record. Used by buffer iterators. Timestamp is only used by channel
	 * iterator.
	 */
	void (*record_get) (const struct lib_ring_buffer_config *config,
			    struct channel *chan, struct lib_ring_buffer *buf,
			    size_t offset, size_t *header_len,
			    size_t *payload_len, u64 *timestamp);
};

/*
 * Ring buffer instance configuration.
 *
 * Declare as "static const" within the client object to ensure the inline fast
 * paths can be optimized.
 *
 * alloc/sync pairs:
 *
 * RING_BUFFER_ALLOC_PER_CPU and RING_BUFFER_SYNC_PER_CPU :
 *   Per-cpu buffers with per-cpu synchronization. Tracing must be performed
 *   with preemption disabled (lib_ring_buffer_get_cpu() and
 *   lib_ring_buffer_put_cpu()).
 *
 * RING_BUFFER_ALLOC_PER_CPU and RING_BUFFER_SYNC_GLOBAL :
 *   Per-cpu buffer with global synchronization. Tracing can be performed with
 *   preemption enabled, statistically stays on the local buffers.
 *
 * RING_BUFFER_ALLOC_GLOBAL and RING_BUFFER_SYNC_PER_CPU :
 *   Should only be used for buffers belonging to a single thread or protected
 *   by mutual exclusion by the client. Note that periodical sub-buffer switch
 *   should be disabled in this kind of configuration.
 *
 * RING_BUFFER_ALLOC_GLOBAL and RING_BUFFER_SYNC_GLOBAL :
 *   Global shared buffer with global synchronization.
 *
 * wakeup:
 *
 * RING_BUFFER_WAKEUP_BY_TIMER uses per-cpu timers to poll the
 * buffers and wake up readers if data is ready. Mainly useful for tracers which
 * don't want to call into the wakeup code on the tracing path. Use in
 * combination with "read_timer_interval" channel_create() argument.
 *
 * RING_BUFFER_WAKEUP_BY_WRITER directly wakes up readers when a subbuffer is
 * ready to read. Lower latencies before the reader is woken up. Mainly suitable
 * for drivers.
 *
 * RING_BUFFER_WAKEUP_NONE does not perform any wakeup whatsoever. The client
 * has the responsibility to perform wakeups.
 */
struct lib_ring_buffer_config {
	enum {
		RING_BUFFER_ALLOC_PER_CPU,
		RING_BUFFER_ALLOC_GLOBAL,
	} alloc;
	enum {
		RING_BUFFER_SYNC_PER_CPU,	/* Wait-free */
		RING_BUFFER_SYNC_GLOBAL,	/* Lock-free */
	} sync;
	enum {
		RING_BUFFER_OVERWRITE,		/* Overwrite when buffer full */
		RING_BUFFER_DISCARD,		/* Discard when buffer full */
	} mode;
	enum {
		RING_BUFFER_SPLICE,
		RING_BUFFER_MMAP,
		RING_BUFFER_READ,		/* TODO */
		RING_BUFFER_ITERATOR,
		RING_BUFFER_NONE,
	} output;
	enum {
		RING_BUFFER_PAGE,
		RING_BUFFER_VMAP,		/* TODO */
		RING_BUFFER_STATIC,		/* TODO */
	} backend;
	enum {
		RING_BUFFER_NO_OOPS_CONSISTENCY,
		RING_BUFFER_OOPS_CONSISTENCY,
	} oops;
	enum {
		RING_BUFFER_IPI_BARRIER,
		RING_BUFFER_NO_IPI_BARRIER,
	} ipi;
	enum {
		RING_BUFFER_WAKEUP_BY_TIMER,	/* wake up performed by timer */
		RING_BUFFER_WAKEUP_BY_WRITER,	/*
						 * writer wakes up reader,
						 * not lock-free
						 * (takes spinlock).
						 */
	} wakeup;
	/*
	 * tsc_bits: timestamp bits saved at each record.
	 *   0 and 64 disable the timestamp compression scheme.
	 */
	unsigned int tsc_bits;
	struct lib_ring_buffer_client_cb cb;
};

/*
 * ring buffer context
 *
 * Context passed to lib_ring_buffer_reserve(), lib_ring_buffer_commit(),
 * lib_ring_buffer_try_discard_reserve(), lib_ring_buffer_align_ctx() and
 * lib_ring_buffer_write().
 */
struct lib_ring_buffer_ctx {
	/* input received by lib_ring_buffer_reserve(), saved here. */
	struct channel *chan;		/* channel */
	void *priv;			/* client private data */
	size_t data_size;		/* size of payload */
	int largest_align;		/*
					 * alignment of the largest element
					 * in the payload
					 */
	int cpu;			/* processor id */

	/* output from lib_ring_buffer_reserve() */
	struct lib_ring_buffer *buf;	/*
					 * buffer corresponding to processor id
					 * for this channel
					 */
	size_t slot_size;		/* size of the reserved slot */
	unsigned long buf_offset;	/* offset following the record header */
	unsigned long pre_offset;	/*
					 * Initial offset position _before_
					 * the record is written. Positioned
					 * prior to record header alignment
					 * padding.
					 */
	u64 tsc;			/* time-stamp counter value */
	unsigned int rflags;		/* reservation flags */
	/* Cache backend pages pointer chasing. */
	struct lib_ring_buffer_backend_pages *backend_pages;
};

/**
 * lib_ring_buffer_ctx_init - initialize ring buffer context
 * @ctx: ring buffer context to initialize
 * @chan: channel
 * @priv: client private data
 * @data_size: size of record data payload. It must be greater than 0.
 * @largest_align: largest alignment within data payload types
 * @cpu: processor id
 */
static inline
void lib_ring_buffer_ctx_init(struct lib_ring_buffer_ctx *ctx,
			      struct channel *chan, void *priv,
			      size_t data_size, int largest_align,
			      int cpu)
{
	ctx->chan = chan;
	ctx->priv = priv;
	ctx->data_size = data_size;
	ctx->largest_align = largest_align;
	ctx->cpu = cpu;
	ctx->rflags = 0;
	ctx->backend_pages = NULL;
}

/*
 * Reservation flags.
 *
 * RING_BUFFER_RFLAG_FULL_TSC
 *
 * This flag is passed to record_header_size() and to the primitive used to
 * write the record header. It indicates that the full 64-bit time value is
 * needed in the record header. If this flag is not set, the record header needs
 * only to contain "tsc_bits" bit of time value.
 *
 * Reservation flags can be added by the client, starting from
 * "(RING_BUFFER_FLAGS_END << 0)". It can be used to pass information from
 * record_header_size() to lib_ring_buffer_write_record_header().
 */
#define	RING_BUFFER_RFLAG_FULL_TSC		(1U << 0)
#define RING_BUFFER_RFLAG_END			(1U << 1)

#ifndef LTTNG_TRACER_CORE_H
#error "lttng-tracer-core.h is needed for RING_BUFFER_ALIGN define"
#endif

/*
 * We need to define RING_BUFFER_ALIGN_ATTR so it is known early at
 * compile-time. We have to duplicate the "config->align" information and the
 * definition here because config->align is used both in the slow and fast
 * paths, but RING_BUFFER_ALIGN_ATTR is only available for the client code.
 */
#ifdef RING_BUFFER_ALIGN

# define RING_BUFFER_ALIGN_ATTR		/* Default arch alignment */

/*
 * Calculate the offset needed to align the type.
 * size_of_type must be non-zero.
 */
static inline
unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type)
{
	return offset_align(align_drift, size_of_type);
}

#else

# define RING_BUFFER_ALIGN_ATTR __attribute__((packed))

/*
 * Calculate the offset needed to align the type.
 * size_of_type must be non-zero.
 */
static inline
unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type)
{
	return 0;
}

#endif

/**
 * lib_ring_buffer_align_ctx - Align context offset on "alignment"
 * @ctx: ring buffer context.
 */
static inline
void lib_ring_buffer_align_ctx(struct lib_ring_buffer_ctx *ctx,
			   size_t alignment)
{
	ctx->buf_offset += lib_ring_buffer_align(ctx->buf_offset,
						 alignment);
}

/*
 * lib_ring_buffer_check_config() returns 0 on success.
 * Used internally to check for valid configurations at channel creation.
 */
static inline
int lib_ring_buffer_check_config(const struct lib_ring_buffer_config *config,
			     unsigned int switch_timer_interval,
			     unsigned int read_timer_interval)
{
	if (config->alloc == RING_BUFFER_ALLOC_GLOBAL
	    && config->sync == RING_BUFFER_SYNC_PER_CPU
	    && switch_timer_interval)
		return -EINVAL;
	return 0;
}

#include <wrapper/ringbuffer/vatomic.h>

#endif /* _LIB_RING_BUFFER_CONFIG_H */
Commit	Line	Data
886d51a3 MD	1	#ifndef _LIB_RING_BUFFER_CONFIG_H
886d51a3 MD	2	#define _LIB_RING_BUFFER_CONFIG_H
f3bc08c5 MD	3
f3bc08c5 MD	4	/*
886d51a3	5	* lib/ringbuffer/config.h
f3bc08c5 MD	6	*
	7	* Ring buffer configuration header. Note: after declaring the standard inline
	8	* functions, clients should also include linux/ringbuffer/api.h.
	9	*
886d51a3 MD	10	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	11	*
	12	* This library is free software; you can redistribute it and/or
	13	* modify it under the terms of the GNU Lesser General Public
	14	* License as published by the Free Software Foundation; only
	15	* version 2.1 of the License.
	16	*
	17	* This library is distributed in the hope that it will be useful,
	18	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	20	* Lesser General Public License for more details.
	21	*
	22	* You should have received a copy of the GNU Lesser General Public
	23	* License along with this library; if not, write to the Free Software
	24	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
f3bc08c5 MD	25	*/
	26
	27	#include <linux/types.h>
	28	#include <linux/percpu.h>
5671a661 MD	29	#include <lib/align.h>
5671a661 MD	30	#include <lttng-tracer-core.h>
f3bc08c5 MD	31
	32	struct lib_ring_buffer;
	33	struct channel;
	34	struct lib_ring_buffer_config;
	35	struct lib_ring_buffer_ctx;
	36
	37	/*
	38	* Ring buffer client callbacks. Only used by slow path, never on fast path.
	39	* For the fast path, record_header_size(), ring_buffer_clock_read() should be
	40	* provided as inline functions too. These may simply return 0 if not used by
	41	* the client.
	42	*/
	43	struct lib_ring_buffer_client_cb {
	44	/* Mandatory callbacks */
	45
	46	/* A static inline version is also required for fast path */
	47	u64 (ring_buffer_clock_read) (struct channel chan);
	48	size_t (record_header_size) (const struct lib_ring_buffer_config config,
	49	struct channel *chan, size_t offset,
f3bc08c5	50	size_t *pre_header_padding,
cc62f29e MD	51	struct lib_ring_buffer_ctx *ctx,
cc62f29e MD	52	void *client_ctx);
f3bc08c5 MD	53
	54	/* Slow path only, at subbuffer switch */
	55	size_t (*subbuffer_header_size) (void);
	56	void (buffer_begin) (struct lib_ring_buffer buf, u64 tsc,
	57	unsigned int subbuf_idx);
	58	void (buffer_end) (struct lib_ring_buffer buf, u64 tsc,
	59	unsigned int subbuf_idx, unsigned long data_size);
	60
	61	/* Optional callbacks (can be set to NULL) */
	62
	63	/* Called at buffer creation/finalize */
	64	int (buffer_create) (struct lib_ring_buffer buf, void *priv,
	65	int cpu, const char *name);
	66	/*
	67	* Clients should guarantee that no new reader handle can be opened
	68	* after finalize.
	69	*/
	70	void (buffer_finalize) (struct lib_ring_buffer buf, void *priv, int cpu);
	71
	72	/*
	73	* Extract header length, payload length and timestamp from event
	74	* record. Used by buffer iterators. Timestamp is only used by channel
	75	* iterator.
	76	*/
	77	void (record_get) (const struct lib_ring_buffer_config config,
	78	struct channel chan, struct lib_ring_buffer buf,
	79	size_t offset, size_t *header_len,
	80	size_t payload_len, u64 timestamp);
	81	};
	82
	83	/*
	84	* Ring buffer instance configuration.
	85	*
	86	* Declare as "static const" within the client object to ensure the inline fast
	87	* paths can be optimized.
	88	*
	89	* alloc/sync pairs:
	90	*
	91	* RING_BUFFER_ALLOC_PER_CPU and RING_BUFFER_SYNC_PER_CPU :
	92	* Per-cpu buffers with per-cpu synchronization. Tracing must be performed
	93	* with preemption disabled (lib_ring_buffer_get_cpu() and
	94	* lib_ring_buffer_put_cpu()).
	95	*
	96	* RING_BUFFER_ALLOC_PER_CPU and RING_BUFFER_SYNC_GLOBAL :
	97	* Per-cpu buffer with global synchronization. Tracing can be performed with
	98	* preemption enabled, statistically stays on the local buffers.
	99	*
	100	* RING_BUFFER_ALLOC_GLOBAL and RING_BUFFER_SYNC_PER_CPU :
	101	* Should only be used for buffers belonging to a single thread or protected
	102	* by mutual exclusion by the client. Note that periodical sub-buffer switch
	103	* should be disabled in this kind of configuration.
	104	*
	105	* RING_BUFFER_ALLOC_GLOBAL and RING_BUFFER_SYNC_GLOBAL :
	106	* Global shared buffer with global synchronization.
	107	*
	108	* wakeup:
	109	*
da9f3fb7	110	* RING_BUFFER_WAKEUP_BY_TIMER uses per-cpu timers to poll the
f3bc08c5 MD	111	* buffers and wake up readers if data is ready. Mainly useful for tracers which
	112	* don't want to call into the wakeup code on the tracing path. Use in
	113	* combination with "read_timer_interval" channel_create() argument.
	114	*
	115	* RING_BUFFER_WAKEUP_BY_WRITER directly wakes up readers when a subbuffer is
	116	* ready to read. Lower latencies before the reader is woken up. Mainly suitable
	117	* for drivers.
	118	*
	119	* RING_BUFFER_WAKEUP_NONE does not perform any wakeup whatsoever. The client
	120	* has the responsibility to perform wakeups.
	121	*/
	122	struct lib_ring_buffer_config {
	123	enum {
	124	RING_BUFFER_ALLOC_PER_CPU,
	125	RING_BUFFER_ALLOC_GLOBAL,
	126	} alloc;
	127	enum {
	128	RING_BUFFER_SYNC_PER_CPU, /* Wait-free */
	129	RING_BUFFER_SYNC_GLOBAL, /* Lock-free */
	130	} sync;
	131	enum {
	132	RING_BUFFER_OVERWRITE, /* Overwrite when buffer full */
	133	RING_BUFFER_DISCARD, /* Discard when buffer full */
	134	} mode;
	135	enum {
	136	RING_BUFFER_SPLICE,
	137	RING_BUFFER_MMAP,
	138	RING_BUFFER_READ, /* TODO */
	139	RING_BUFFER_ITERATOR,
	140	RING_BUFFER_NONE,
	141	} output;
	142	enum {
	143	RING_BUFFER_PAGE,
	144	RING_BUFFER_VMAP, /* TODO */
	145	RING_BUFFER_STATIC, /* TODO */
	146	} backend;
	147	enum {
	148	RING_BUFFER_NO_OOPS_CONSISTENCY,
	149	RING_BUFFER_OOPS_CONSISTENCY,
	150	} oops;
	151	enum {
	152	RING_BUFFER_IPI_BARRIER,
	153	RING_BUFFER_NO_IPI_BARRIER,
	154	} ipi;
	155	enum {
	156	RING_BUFFER_WAKEUP_BY_TIMER, /* wake up performed by timer */
	157	RING_BUFFER_WAKEUP_BY_WRITER, /*
	158	* writer wakes up reader,
	159	* not lock-free
	160	* (takes spinlock).
	161	*/
	162	} wakeup;
	163	/*
	164	* tsc_bits: timestamp bits saved at each record.
	165	* 0 and 64 disable the timestamp compression scheme.
	166	*/
	167	unsigned int tsc_bits;
	168	struct lib_ring_buffer_client_cb cb;
	169	};
	170
	171	/*
	172	* ring buffer context
	173	*
	174	* Context passed to lib_ring_buffer_reserve(), lib_ring_buffer_commit(),
175	* lib_ring_buffer_try_discard_reserve(), lib_ring_buffer_align_ctx() and
176	* lib_ring_buffer_write().
177	*/
178	struct lib_ring_buffer_ctx {
179	/* input received by lib_ring_buffer_reserve(), saved here. */
180	struct channel chan; / channel */
181	void priv; / client private data */
182	size_t data_size; /* size of payload */
183	int largest_align; /*
184	* alignment of the largest element
185	* in the payload
186	*/
187	int cpu; /* processor id */
188
189	/* output from lib_ring_buffer_reserve() */
190	struct lib_ring_buffer buf; /
191	* buffer corresponding to processor id
192	* for this channel
193	*/
194	size_t slot_size; /* size of the reserved slot */
195	unsigned long buf_offset; /* offset following the record header */
196	unsigned long pre_offset; /*
197	* Initial offset position _before_
198	* the record is written. Positioned
199	* prior to record header alignment
200	* padding.
201	*/
202	u64 tsc; /* time-stamp counter value */
203	unsigned int rflags; /* reservation flags */
85a07c33 MD	204	/* Cache backend pages pointer chasing. */
85a07c33 MD	205	struct lib_ring_buffer_backend_pages *backend_pages;
f3bc08c5 MD	206	};
	207
	208	/**
	209	* lib_ring_buffer_ctx_init - initialize ring buffer context
	210	* @ctx: ring buffer context to initialize
	211	* @chan: channel
	212	* @priv: client private data
3cae7f22	213	* @data_size: size of record data payload. It must be greater than 0.
f3bc08c5 MD	214	* @largest_align: largest alignment within data payload types
	215	* @cpu: processor id
	216	*/
	217	static inline
	218	void lib_ring_buffer_ctx_init(struct lib_ring_buffer_ctx *ctx,
	219	struct channel chan, void priv,
	220	size_t data_size, int largest_align,
	221	int cpu)
	222	{
	223	ctx->chan = chan;
	224	ctx->priv = priv;
	225	ctx->data_size = data_size;
	226	ctx->largest_align = largest_align;
	227	ctx->cpu = cpu;
64c796d8	228	ctx->rflags = 0;
85a07c33	229	ctx->backend_pages = NULL;
f3bc08c5 MD	230	}
	231
	232	/*
	233	* Reservation flags.
	234	*
	235	* RING_BUFFER_RFLAG_FULL_TSC
	236	*
	237	* This flag is passed to record_header_size() and to the primitive used to
	238	* write the record header. It indicates that the full 64-bit time value is
	239	* needed in the record header. If this flag is not set, the record header needs
	240	* only to contain "tsc_bits" bit of time value.
	241	*
	242	* Reservation flags can be added by the client, starting from
	243	* "(RING_BUFFER_FLAGS_END << 0)". It can be used to pass information from
	244	* record_header_size() to lib_ring_buffer_write_record_header().
	245	*/
	246	#define RING_BUFFER_RFLAG_FULL_TSC (1U << 0)
	247	#define RING_BUFFER_RFLAG_END (1U << 1)
	248
ae090dc5 MD	249	#ifndef LTTNG_TRACER_CORE_H
	250	#error "lttng-tracer-core.h is needed for RING_BUFFER_ALIGN define"
	251	#endif
	252
f3bc08c5 MD	253	/*
	254	* We need to define RING_BUFFER_ALIGN_ATTR so it is known early at
	255	* compile-time. We have to duplicate the "config->align" information and the
	256	* definition here because config->align is used both in the slow and fast
	257	* paths, but RING_BUFFER_ALIGN_ATTR is only available for the client code.
	258	*/
	259	#ifdef RING_BUFFER_ALIGN
	260
	261	# define RING_BUFFER_ALIGN_ATTR /* Default arch alignment */
	262
	263	/*
	264	* Calculate the offset needed to align the type.
	265	* size_of_type must be non-zero.
	266	*/
	267	static inline
	268	unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type)
	269	{
	270	return offset_align(align_drift, size_of_type);
	271	}
	272
	273	#else
	274
	275	# define RING_BUFFER_ALIGN_ATTR __attribute__((packed))
	276
	277	/*
	278	* Calculate the offset needed to align the type.
	279	* size_of_type must be non-zero.
	280	*/
	281	static inline
	282	unsigned int lib_ring_buffer_align(size_t align_drift, size_t size_of_type)
	283	{
	284	return 0;
	285	}
	286
	287	#endif
	288
	289	/**
	290	* lib_ring_buffer_align_ctx - Align context offset on "alignment"
	291	* @ctx: ring buffer context.
	292	*/
	293	static inline
	294	void lib_ring_buffer_align_ctx(struct lib_ring_buffer_ctx *ctx,
	295	size_t alignment)
	296	{
	297	ctx->buf_offset += lib_ring_buffer_align(ctx->buf_offset,
	298	alignment);
	299	}
	300
	301	/*
	302	* lib_ring_buffer_check_config() returns 0 on success.
	303	* Used internally to check for valid configurations at channel creation.
	304	*/
	305	static inline
	306	int lib_ring_buffer_check_config(const struct lib_ring_buffer_config *config,
	307	unsigned int switch_timer_interval,
	308	unsigned int read_timer_interval)
	309	{
	310	if (config->alloc == RING_BUFFER_ALLOC_GLOBAL
	311	&& config->sync == RING_BUFFER_SYNC_PER_CPU
	312	&& switch_timer_interval)
	313	return -EINVAL;
	314	return 0;
	315	}
	316
c075712b	317	#include <wrapper/ringbuffer/vatomic.h>
f3bc08c5	318
886d51a3	319	#endif /* _LIB_RING_BUFFER_CONFIG_H */