[lttng-ust.git] / liblttng-ust / lttng-ring-buffer-metadata-client.h

/*
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * LTTng lib ring buffer client template.
 */

#include <stddef.h>
#include <stdint.h>
#include <lttng/ust-events.h>
#include "lttng/bitfield.h"
#include "lttng-tracer.h"
#include "../libringbuffer/frontend_types.h"

struct metadata_packet_header {
	uint32_t magic;			/* 0x75D11D57 */
	uint8_t  uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */
	uint32_t checksum;		/* 0 if unused */
	uint32_t content_size;		/* in bits */
	uint32_t packet_size;		/* in bits */
	uint8_t  compression_scheme;	/* 0 if unused */
	uint8_t  encryption_scheme;	/* 0 if unused */
	uint8_t  checksum_scheme;	/* 0 if unused */
	uint8_t  major;			/* CTF spec major version number */
	uint8_t  minor;			/* CTF spec minor version number */
	uint8_t  header_end[0];
};

struct metadata_record_header {
	uint8_t header_end[0];		/* End of header */
};

static const struct lttng_ust_lib_ring_buffer_config client_config;

static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
{
	return 0;
}

static inline
size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
				 struct channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lttng_ust_lib_ring_buffer_ctx *ctx,
				 void *client_ctx)
{
	return 0;
}

#include "../libringbuffer/api.h"
#include "lttng-rb-clients.h"

static uint64_t client_ring_buffer_clock_read(struct channel *chan)
{
	return 0;
}

static
size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
				 struct channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lttng_ust_lib_ring_buffer_ctx *ctx,
				 void *client_ctx)
{
	return 0;
}

/**
 * client_packet_header_size - called on buffer-switch to a new sub-buffer
 *
 * Return header size without padding after the structure. Don't use packed
 * structure because gcc generates inefficient code on some architectures
 * (powerpc, mips..)
 */
static size_t client_packet_header_size(void)
{
	return offsetof(struct metadata_packet_header, header_end);
}

static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
				unsigned int subbuf_idx,
				struct lttng_ust_shm_handle *handle)
{
	struct channel *chan = shmp(handle, buf->backend.chan);
	struct metadata_packet_header *header =
		(struct metadata_packet_header *)
			lib_ring_buffer_offset_address(&buf->backend,
				subbuf_idx * chan->backend.subbuf_size,
				handle);
	struct lttng_channel *lttng_chan = channel_get_private(chan);

	assert(header);
	if (!header)
		return;
	header->magic = TSDL_MAGIC_NUMBER;
	memcpy(header->uuid, lttng_chan->uuid, sizeof(lttng_chan->uuid));
	header->checksum = 0;		/* 0 if unused */
	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	header->packet_size = 0xFFFFFFFF;  /* in bits, for debugging */
	header->compression_scheme = 0;	/* 0 if unused */
	header->encryption_scheme = 0;	/* 0 if unused */
	header->checksum_scheme = 0;	/* 0 if unused */
	header->major = CTF_SPEC_MAJOR;
	header->minor = CTF_SPEC_MINOR;
}

/*
 * offset is assumed to never be 0 here : never deliver a completely empty
 * subbuffer. data_size is between 1 and subbuf_size.
 */
static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
			      unsigned int subbuf_idx, unsigned long data_size,
			      struct lttng_ust_shm_handle *handle)
{
	struct channel *chan = shmp(handle, buf->backend.chan);
	struct metadata_packet_header *header =
		(struct metadata_packet_header *)
			lib_ring_buffer_offset_address(&buf->backend,
				subbuf_idx * chan->backend.subbuf_size,
				handle);
	unsigned long records_lost = 0;

	assert(header);
	if (!header)
		return;
	header->content_size = data_size * CHAR_BIT;		/* in bits */
	header->packet_size = LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
	/*
	 * We do not care about the records lost count, because the metadata
	 * channel waits and retry.
	 */
	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	WARN_ON_ONCE(records_lost != 0);
}

static int client_buffer_create(struct lttng_ust_lib_ring_buffer *buf, void *priv,
				int cpu, const char *name,
				struct lttng_ust_shm_handle *handle)
{
	return 0;
}

static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
				   void *priv, int cpu,
				   struct lttng_ust_shm_handle *handle)
{
}

static const
struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = {
	.parent = {
		.ring_buffer_clock_read = client_ring_buffer_clock_read,
		.record_header_size = client_record_header_size,
		.subbuffer_header_size = client_packet_header_size,
		.buffer_begin = client_buffer_begin,
		.buffer_end = client_buffer_end,
		.buffer_create = client_buffer_create,
		.buffer_finalize = client_buffer_finalize,
	},
};

static const struct lttng_ust_lib_ring_buffer_config client_config = {
	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	.cb.record_header_size = client_record_header_size,
	.cb.subbuffer_header_size = client_packet_header_size,
	.cb.buffer_begin = client_buffer_begin,
	.cb.buffer_end = client_buffer_end,
	.cb.buffer_create = client_buffer_create,
	.cb.buffer_finalize = client_buffer_finalize,

	.tsc_bits = 0,
	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	.sync = RING_BUFFER_SYNC_GLOBAL,
	.mode = RING_BUFFER_MODE_TEMPLATE,
	.backend = RING_BUFFER_PAGE,
	.output = RING_BUFFER_MMAP,
	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	.ipi = RING_BUFFER_NO_IPI_BARRIER,
	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
	.client_type = LTTNG_CLIENT_TYPE,

	 .cb_ptr = &client_cb.parent,
};

const struct lttng_ust_client_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_cb;

static
struct lttng_channel *_channel_create(const char *name,
				void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval,
				unsigned char *uuid,
				uint32_t chan_id,
				const int *stream_fds, int nr_stream_fds,
				int64_t blocking_timeout)
{
	struct lttng_channel chan_priv_init;
	struct lttng_ust_shm_handle *handle;
	struct lttng_channel *lttng_chan;
	void *priv;

	memset(&chan_priv_init, 0, sizeof(chan_priv_init));
	memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN);
	chan_priv_init.id = chan_id;
	handle = channel_create(&client_config, name,
			&priv, __alignof__(struct lttng_channel),
			sizeof(struct lttng_channel),
			&chan_priv_init,
			buf_addr, subbuf_size, num_subbuf,
			switch_timer_interval, read_timer_interval,
			stream_fds, nr_stream_fds, blocking_timeout);
	if (!handle)
		return NULL;
	lttng_chan = priv;
	lttng_chan->handle = handle;
	lttng_chan->chan = shmp(handle, handle->chan);
	return lttng_chan;
}

static
void lttng_channel_destroy(struct lttng_channel *chan)
{
	channel_destroy(chan->chan, chan->handle, 1);
}

static
int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
{
	int ret;

	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
	if (ret)
		return ret;
	if (caa_likely(ctx->ctx_len
			>= sizeof(struct lttng_ust_lib_ring_buffer_ctx))) {
		if (lib_ring_buffer_backend_get_pages(&client_config, ctx,
				&ctx->backend_pages))
			return -EPERM;
	}
	return 0;
}

static
void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
{
	lib_ring_buffer_commit(&client_config, ctx);
}

static
void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx *ctx, const void *src,
		     size_t len)
{
	lib_ring_buffer_write(&client_config, ctx, src, len);
}

static
size_t lttng_packet_avail_size(struct channel *chan, struct lttng_ust_shm_handle *handle)
{
	unsigned long o_begin;
	struct lttng_ust_lib_ring_buffer *buf;

	buf = shmp(handle, chan->backend.buf[0].shmp);	/* Only for global buffer ! */
	o_begin = v_read(&client_config, &buf->offset);
	if (subbuf_offset(o_begin, chan) != 0) {
		return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	} else {
		return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
			- sizeof(struct metadata_packet_header);
	}
}

#if 0
static
wait_queue_head_t *lttng_get_reader_wait_queue(struct channel *chan)
{
	return &chan->read_wait;
}

static
wait_queue_head_t *lttng_get_hp_wait_queue(struct channel *chan)
{
	return &chan->hp_wait;
}
#endif //0

static
int lttng_is_finalized(struct channel *chan)
{
	return lib_ring_buffer_channel_is_finalized(chan);
}

static
int lttng_is_disabled(struct channel *chan)
{
	return lib_ring_buffer_channel_is_disabled(chan);
}

static
int lttng_flush_buffer(struct channel *chan, struct lttng_ust_shm_handle *handle)
{
	struct lttng_ust_lib_ring_buffer *buf;
	int shm_fd, wait_fd, wakeup_fd;
	uint64_t memory_map_size;

	buf = channel_get_ring_buffer(&client_config, chan,
			0, handle, &shm_fd, &wait_fd, &wakeup_fd,
			&memory_map_size);
	lib_ring_buffer_switch(&client_config, buf,
			SWITCH_ACTIVE, handle);
	return 0;
}

static struct lttng_transport lttng_relay_transport = {
	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
	.ops = {
		.channel_create = _channel_create,
		.channel_destroy = lttng_channel_destroy,
		.event_reserve = lttng_event_reserve,
		.event_commit = lttng_event_commit,
		.event_write = lttng_event_write,
		.packet_avail_size = lttng_packet_avail_size,
		//.get_reader_wait_queue = lttng_get_reader_wait_queue,
		//.get_hp_wait_queue = lttng_get_hp_wait_queue,
		.is_finalized = lttng_is_finalized,
		.is_disabled = lttng_is_disabled,
		.flush_buffer = lttng_flush_buffer,
	},
	.client_config = &client_config,
};

void RING_BUFFER_MODE_TEMPLATE_INIT(void)
{
	DBG("LTT : ltt ring buffer client \"%s\" init\n",
		"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
	lttng_transport_register(&lttng_relay_transport);
}

void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
{
	DBG("LTT : ltt ring buffer client \"%s\" exit\n",
		"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
	lttng_transport_unregister(&lttng_relay_transport);
}
Commit	Line	Data
3d1fc7fd	1	/*
c0c0989a	2	* SPDX-License-Identifier: LGPL-2.1-only
3d1fc7fd	3	*
e92f3e28 MD	4	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
e92f3e28 MD	5	*
c0c0989a	6	* LTTng lib ring buffer client template.
3d1fc7fd MD	7	*/
3d1fc7fd MD	8
b4051ad8	9	#include <stddef.h>
9f3fdbc6	10	#include <stdint.h>
4318ae1b MD	11	#include <lttng/ust-events.h>
4318ae1b MD	12	#include "lttng/bitfield.h"
7dd08bec	13	#include "lttng-tracer.h"
9f3fdbc6	14	#include "../libringbuffer/frontend_types.h"
3d1fc7fd MD	15
	16	struct metadata_packet_header {
	17	uint32_t magic; /* 0x75D11D57 */
19d8b1b3	18	uint8_t uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */
3d1fc7fd MD	19	uint32_t checksum; /* 0 if unused */
	20	uint32_t content_size; /* in bits */
	21	uint32_t packet_size; /* in bits */
	22	uint8_t compression_scheme; /* 0 if unused */
	23	uint8_t encryption_scheme; /* 0 if unused */
	24	uint8_t checksum_scheme; /* 0 if unused */
8a98a75d MD	25	uint8_t major; /* CTF spec major version number */
8a98a75d MD	26	uint8_t minor; /* CTF spec minor version number */
3d1fc7fd MD	27	uint8_t header_end[0];
	28	};
	29
	30	struct metadata_record_header {
	31	uint8_t header_end[0]; /* End of header */
	32	};
	33
4cfec15c	34	static const struct lttng_ust_lib_ring_buffer_config client_config;
3d1fc7fd	35
23c8854a	36	static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
3d1fc7fd MD	37	{
	38	return 0;
	39	}
	40
	41	static inline
8ca68914	42	size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
3d1fc7fd MD	43	struct channel *chan, size_t offset,
3d1fc7fd MD	44	size_t *pre_header_padding,
e56bb47c MD	45	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e56bb47c MD	46	void *client_ctx)
3d1fc7fd MD	47	{
	48	return 0;
	49	}
	50
9f3fdbc6	51	#include "../libringbuffer/api.h"
82b9bde8	52	#include "lttng-rb-clients.h"
3d1fc7fd	53
23c8854a	54	static uint64_t client_ring_buffer_clock_read(struct channel *chan)
3d1fc7fd MD	55	{
	56	return 0;
	57	}
	58
	59	static
4cfec15c	60	size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
3d1fc7fd MD	61	struct channel *chan, size_t offset,
3d1fc7fd MD	62	size_t *pre_header_padding,
e56bb47c MD	63	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e56bb47c MD	64	void *client_ctx)
3d1fc7fd MD	65	{
	66	return 0;
	67	}
	68
	69	/**
	70	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	71	*
	72	* Return header size without padding after the structure. Don't use packed
	73	* structure because gcc generates inefficient code on some architectures
	74	* (powerpc, mips..)
	75	*/
	76	static size_t client_packet_header_size(void)
	77	{
	78	return offsetof(struct metadata_packet_header, header_end);
	79	}
	80
23c8854a	81	static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
1d498196	82	unsigned int subbuf_idx,
38fae1d3	83	struct lttng_ust_shm_handle *handle)
3d1fc7fd	84	{
1d498196	85	struct channel *chan = shmp(handle, buf->backend.chan);
3d1fc7fd MD	86	struct metadata_packet_header *header =
	87	(struct metadata_packet_header *)
	88	lib_ring_buffer_offset_address(&buf->backend,
1d498196 MD	89	subbuf_idx * chan->backend.subbuf_size,
1d498196 MD	90	handle);
7dd08bec	91	struct lttng_channel *lttng_chan = channel_get_private(chan);
3d1fc7fd	92
34daae3e MD	93	assert(header);
	94	if (!header)
	95	return;
3d1fc7fd	96	header->magic = TSDL_MAGIC_NUMBER;
7dd08bec	97	memcpy(header->uuid, lttng_chan->uuid, sizeof(lttng_chan->uuid));
3d1fc7fd MD	98	header->checksum = 0; /* 0 if unused */
	99	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	100	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	101	header->compression_scheme = 0; /* 0 if unused */
	102	header->encryption_scheme = 0; /* 0 if unused */
	103	header->checksum_scheme = 0; /* 0 if unused */
8a98a75d MD	104	header->major = CTF_SPEC_MAJOR;
8a98a75d MD	105	header->minor = CTF_SPEC_MINOR;
3d1fc7fd MD	106	}
	107
	108	/*
	109	* offset is assumed to never be 0 here : never deliver a completely empty
	110	* subbuffer. data_size is between 1 and subbuf_size.
	111	*/
23c8854a	112	static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
1d498196	113	unsigned int subbuf_idx, unsigned long data_size,
38fae1d3	114	struct lttng_ust_shm_handle *handle)
3d1fc7fd	115	{
1d498196	116	struct channel *chan = shmp(handle, buf->backend.chan);
3d1fc7fd MD	117	struct metadata_packet_header *header =
	118	(struct metadata_packet_header *)
	119	lib_ring_buffer_offset_address(&buf->backend,
1d498196 MD	120	subbuf_idx * chan->backend.subbuf_size,
1d498196 MD	121	handle);
3d1fc7fd MD	122	unsigned long records_lost = 0;
3d1fc7fd MD	123
34daae3e MD	124	assert(header);
	125	if (!header)
	126	return;
3d1fc7fd	127	header->content_size = data_size * CHAR_BIT; /* in bits */
b72687b8	128	header->packet_size = LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
04489ab4 MD	129	/*
	130	* We do not care about the records lost count, because the metadata
	131	* channel waits and retry.
	132	*/
	133	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
3d1fc7fd MD	134	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	135	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	136	WARN_ON_ONCE(records_lost != 0);
	137	}
	138
4cfec15c	139	static int client_buffer_create(struct lttng_ust_lib_ring_buffer buf, void priv,
1d498196	140	int cpu, const char *name,
38fae1d3	141	struct lttng_ust_shm_handle *handle)
3d1fc7fd MD	142	{
	143	return 0;
	144	}
	145
4cfec15c	146	static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
1d498196	147	void *priv, int cpu,
38fae1d3	148	struct lttng_ust_shm_handle *handle)
3d1fc7fd MD	149	{
	150	}
	151
82b9bde8 JD	152	static const
	153	struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = {
	154	.parent = {
	155	.ring_buffer_clock_read = client_ring_buffer_clock_read,
	156	.record_header_size = client_record_header_size,
	157	.subbuffer_header_size = client_packet_header_size,
	158	.buffer_begin = client_buffer_begin,
	159	.buffer_end = client_buffer_end,
	160	.buffer_create = client_buffer_create,
	161	.buffer_finalize = client_buffer_finalize,
	162	},
	163	};
	164
4cfec15c	165	static const struct lttng_ust_lib_ring_buffer_config client_config = {
3d1fc7fd MD	166	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	167	.cb.record_header_size = client_record_header_size,
	168	.cb.subbuffer_header_size = client_packet_header_size,
	169	.cb.buffer_begin = client_buffer_begin,
	170	.cb.buffer_end = client_buffer_end,
	171	.cb.buffer_create = client_buffer_create,
	172	.cb.buffer_finalize = client_buffer_finalize,
	173
	174	.tsc_bits = 0,
	175	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	176	.sync = RING_BUFFER_SYNC_GLOBAL,
	177	.mode = RING_BUFFER_MODE_TEMPLATE,
	178	.backend = RING_BUFFER_PAGE,
5d61a504	179	.output = RING_BUFFER_MMAP,
3d1fc7fd	180	.oops = RING_BUFFER_OOPS_CONSISTENCY,
5d61a504 MD	181	.ipi = RING_BUFFER_NO_IPI_BARRIER,
5d61a504 MD	182	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
c1fca457	183	.client_type = LTTNG_CLIENT_TYPE,
82b9bde8 JD	184
82b9bde8 JD	185	.cb_ptr = &client_cb.parent,
3d1fc7fd MD	186	};
3d1fc7fd MD	187
82b9bde8	188	const struct lttng_ust_client_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_cb;
c1fca457	189
3d1fc7fd	190	static
7dd08bec	191	struct lttng_channel _channel_create(const char name,
a3f61e7f	192	void *buf_addr,
3d1fc7fd MD	193	size_t subbuf_size, size_t num_subbuf,
3d1fc7fd MD	194	unsigned int switch_timer_interval,
193183fb	195	unsigned int read_timer_interval,
6ca18e66	196	unsigned char *uuid,
a9ff648c	197	uint32_t chan_id,
b2c5f61a MD	198	const int *stream_fds, int nr_stream_fds,
b2c5f61a MD	199	int64_t blocking_timeout)
3d1fc7fd	200	{
74d81a6c	201	struct lttng_channel chan_priv_init;
a3f61e7f	202	struct lttng_ust_shm_handle *handle;
74d81a6c MD	203	struct lttng_channel *lttng_chan;
74d81a6c MD	204	void *priv;
a3f61e7f	205
74d81a6c MD	206	memset(&chan_priv_init, 0, sizeof(chan_priv_init));
74d81a6c MD	207	memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN);
6ca18e66	208	chan_priv_init.id = chan_id;
a3f61e7f	209	handle = channel_create(&client_config, name,
8824f307 MD	210	&priv, __alignof__(struct lttng_channel),
8824f307 MD	211	sizeof(struct lttng_channel),
74d81a6c	212	&chan_priv_init,
a3f61e7f	213	buf_addr, subbuf_size, num_subbuf,
a9ff648c	214	switch_timer_interval, read_timer_interval,
b2c5f61a	215	stream_fds, nr_stream_fds, blocking_timeout);
a3f61e7f	216	if (!handle)
1b2c2540	217	return NULL;
7dd08bec MD	218	lttng_chan = priv;
7dd08bec MD	219	lttng_chan->handle = handle;
74d81a6c	220	lttng_chan->chan = shmp(handle, handle->chan);
7dd08bec	221	return lttng_chan;
3d1fc7fd MD	222	}
	223
	224	static
74d81a6c	225	void lttng_channel_destroy(struct lttng_channel *chan)
3d1fc7fd	226	{
74d81a6c	227	channel_destroy(chan->chan, chan->handle, 1);
3d1fc7fd MD	228	}
	229
	230	static
7dd08bec	231	int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
3d1fc7fd	232	{
a3492932 MD	233	int ret;
a3492932 MD	234
e56bb47c	235	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
a3492932 MD	236	if (ret)
	237	return ret;
	238	if (caa_likely(ctx->ctx_len
	239	>= sizeof(struct lttng_ust_lib_ring_buffer_ctx))) {
	240	if (lib_ring_buffer_backend_get_pages(&client_config, ctx,
	241	&ctx->backend_pages))
	242	return -EPERM;
	243	}
	244	return 0;
3d1fc7fd MD	245	}
	246
	247	static
7dd08bec	248	void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
3d1fc7fd MD	249	{
	250	lib_ring_buffer_commit(&client_config, ctx);
	251	}
	252
	253	static
7dd08bec	254	void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx ctx, const void src,
3d1fc7fd MD	255	size_t len)
	256	{
	257	lib_ring_buffer_write(&client_config, ctx, src, len);
	258	}
	259
	260	static
7dd08bec	261	size_t lttng_packet_avail_size(struct channel chan, struct lttng_ust_shm_handle handle)
3d1fc7fd MD	262	{
3d1fc7fd MD	263	unsigned long o_begin;
4cfec15c	264	struct lttng_ust_lib_ring_buffer *buf;
3d1fc7fd	265
1d498196	266	buf = shmp(handle, chan->backend.buf[0].shmp); /* Only for global buffer ! */
3d1fc7fd MD	267	o_begin = v_read(&client_config, &buf->offset);
	268	if (subbuf_offset(o_begin, chan) != 0) {
	269	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	270	} else {
	271	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	272	- sizeof(struct metadata_packet_header);
	273	}
	274	}
	275
9f3fdbc6	276	#if 0
3d1fc7fd	277	static
7dd08bec	278	wait_queue_head_t lttng_get_reader_wait_queue(struct channel chan)
3d1fc7fd MD	279	{
	280	return &chan->read_wait;
	281	}
	282
	283	static
7dd08bec	284	wait_queue_head_t lttng_get_hp_wait_queue(struct channel chan)
3d1fc7fd MD	285	{
	286	return &chan->hp_wait;
	287	}
9f3fdbc6	288	#endif //0
3d1fc7fd MD	289
3d1fc7fd MD	290	static
7dd08bec	291	int lttng_is_finalized(struct channel *chan)
3d1fc7fd MD	292	{
	293	return lib_ring_buffer_channel_is_finalized(chan);
	294	}
	295
	296	static
7dd08bec	297	int lttng_is_disabled(struct channel *chan)
3d1fc7fd MD	298	{
	299	return lib_ring_buffer_channel_is_disabled(chan);
	300	}
	301
43861eab	302	static
7dd08bec	303	int lttng_flush_buffer(struct channel chan, struct lttng_ust_shm_handle handle)
43861eab	304	{
4cfec15c	305	struct lttng_ust_lib_ring_buffer *buf;
74d81a6c MD	306	int shm_fd, wait_fd, wakeup_fd;
74d81a6c MD	307	uint64_t memory_map_size;
43861eab MD	308
43861eab MD	309	buf = channel_get_ring_buffer(&client_config, chan,
74d81a6c	310	0, handle, &shm_fd, &wait_fd, &wakeup_fd,
43861eab MD	311	&memory_map_size);
	312	lib_ring_buffer_switch(&client_config, buf,
	313	SWITCH_ACTIVE, handle);
	314	return 0;
	315	}
	316
7dd08bec	317	static struct lttng_transport lttng_relay_transport = {
818173b9	318	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
3d1fc7fd MD	319	.ops = {
3d1fc7fd MD	320	.channel_create = _channel_create,
7dd08bec	321	.channel_destroy = lttng_channel_destroy,
7dd08bec MD	322	.event_reserve = lttng_event_reserve,
	323	.event_commit = lttng_event_commit,
	324	.event_write = lttng_event_write,
	325	.packet_avail_size = lttng_packet_avail_size,
	326	//.get_reader_wait_queue = lttng_get_reader_wait_queue,
	327	//.get_hp_wait_queue = lttng_get_hp_wait_queue,
	328	.is_finalized = lttng_is_finalized,
	329	.is_disabled = lttng_is_disabled,
	330	.flush_buffer = lttng_flush_buffer,
3d1fc7fd	331	},
74d81a6c	332	.client_config = &client_config,
3d1fc7fd MD	333	};
3d1fc7fd MD	334
edaa1431	335	void RING_BUFFER_MODE_TEMPLATE_INIT(void)
3d1fc7fd	336	{
34a91bdb MD	337	DBG("LTT : ltt ring buffer client \"%s\" init\n",
34a91bdb MD	338	"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
7dd08bec	339	lttng_transport_register(&lttng_relay_transport);
3d1fc7fd MD	340	}
3d1fc7fd MD	341
edaa1431	342	void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
3d1fc7fd	343	{
34a91bdb MD	344	DBG("LTT : ltt ring buffer client \"%s\" exit\n",
34a91bdb MD	345	"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
7dd08bec	346	lttng_transport_unregister(&lttng_relay_transport);
3d1fc7fd	347	}