[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 "ust-bitfield.h"
#include "ust-compat.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	11	#include <lttng/ust-events.h>
ae4b659d	12	#include "ust-bitfield.h"
cd61d9bf	13	#include "ust-compat.h"
7dd08bec	14	#include "lttng-tracer.h"
9f3fdbc6	15	#include "../libringbuffer/frontend_types.h"
3d1fc7fd MD	16
	17	struct metadata_packet_header {
	18	uint32_t magic; /* 0x75D11D57 */
19d8b1b3	19	uint8_t uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */
3d1fc7fd MD	20	uint32_t checksum; /* 0 if unused */
	21	uint32_t content_size; /* in bits */
	22	uint32_t packet_size; /* in bits */
	23	uint8_t compression_scheme; /* 0 if unused */
	24	uint8_t encryption_scheme; /* 0 if unused */
	25	uint8_t checksum_scheme; /* 0 if unused */
8a98a75d MD	26	uint8_t major; /* CTF spec major version number */
8a98a75d MD	27	uint8_t minor; /* CTF spec minor version number */
3d1fc7fd MD	28	uint8_t header_end[0];
	29	};
	30
	31	struct metadata_record_header {
	32	uint8_t header_end[0]; /* End of header */
	33	};
	34
4cfec15c	35	static const struct lttng_ust_lib_ring_buffer_config client_config;
3d1fc7fd	36
23c8854a	37	static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
3d1fc7fd MD	38	{
	39	return 0;
	40	}
	41
	42	static inline
8ca68914	43	size_t record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
3d1fc7fd MD	44	struct channel *chan, size_t offset,
3d1fc7fd MD	45	size_t *pre_header_padding,
e56bb47c MD	46	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e56bb47c MD	47	void *client_ctx)
3d1fc7fd MD	48	{
	49	return 0;
	50	}
	51
9f3fdbc6	52	#include "../libringbuffer/api.h"
82b9bde8	53	#include "lttng-rb-clients.h"
3d1fc7fd	54
23c8854a	55	static uint64_t client_ring_buffer_clock_read(struct channel *chan)
3d1fc7fd MD	56	{
	57	return 0;
	58	}
	59
	60	static
4cfec15c	61	size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
3d1fc7fd MD	62	struct channel *chan, size_t offset,
3d1fc7fd MD	63	size_t *pre_header_padding,
e56bb47c MD	64	struct lttng_ust_lib_ring_buffer_ctx *ctx,
e56bb47c MD	65	void *client_ctx)
3d1fc7fd MD	66	{
	67	return 0;
	68	}
	69
	70	/**
	71	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	72	*
	73	* Return header size without padding after the structure. Don't use packed
	74	* structure because gcc generates inefficient code on some architectures
	75	* (powerpc, mips..)
	76	*/
	77	static size_t client_packet_header_size(void)
	78	{
	79	return offsetof(struct metadata_packet_header, header_end);
	80	}
	81
23c8854a	82	static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
1d498196	83	unsigned int subbuf_idx,
38fae1d3	84	struct lttng_ust_shm_handle *handle)
3d1fc7fd	85	{
1d498196	86	struct channel *chan = shmp(handle, buf->backend.chan);
3d1fc7fd MD	87	struct metadata_packet_header *header =
	88	(struct metadata_packet_header *)
	89	lib_ring_buffer_offset_address(&buf->backend,
1d498196 MD	90	subbuf_idx * chan->backend.subbuf_size,
1d498196 MD	91	handle);
7dd08bec	92	struct lttng_channel *lttng_chan = channel_get_private(chan);
3d1fc7fd	93
34daae3e MD	94	assert(header);
	95	if (!header)
	96	return;
3d1fc7fd	97	header->magic = TSDL_MAGIC_NUMBER;
7dd08bec	98	memcpy(header->uuid, lttng_chan->uuid, sizeof(lttng_chan->uuid));
3d1fc7fd MD	99	header->checksum = 0; /* 0 if unused */
	100	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	101	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	102	header->compression_scheme = 0; /* 0 if unused */
	103	header->encryption_scheme = 0; /* 0 if unused */
	104	header->checksum_scheme = 0; /* 0 if unused */
8a98a75d MD	105	header->major = CTF_SPEC_MAJOR;
8a98a75d MD	106	header->minor = CTF_SPEC_MINOR;
3d1fc7fd MD	107	}
	108
	109	/*
	110	* offset is assumed to never be 0 here : never deliver a completely empty
	111	* subbuffer. data_size is between 1 and subbuf_size.
	112	*/
23c8854a	113	static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
1d498196	114	unsigned int subbuf_idx, unsigned long data_size,
38fae1d3	115	struct lttng_ust_shm_handle *handle)
3d1fc7fd	116	{
1d498196	117	struct channel *chan = shmp(handle, buf->backend.chan);
3d1fc7fd MD	118	struct metadata_packet_header *header =
	119	(struct metadata_packet_header *)
	120	lib_ring_buffer_offset_address(&buf->backend,
1d498196 MD	121	subbuf_idx * chan->backend.subbuf_size,
1d498196 MD	122	handle);
3d1fc7fd MD	123	unsigned long records_lost = 0;
3d1fc7fd MD	124
34daae3e MD	125	assert(header);
	126	if (!header)
	127	return;
3d1fc7fd	128	header->content_size = data_size * CHAR_BIT; /* in bits */
b72687b8	129	header->packet_size = LTTNG_UST_PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
04489ab4 MD	130	/*
	131	* We do not care about the records lost count, because the metadata
	132	* channel waits and retry.
	133	*/
	134	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
3d1fc7fd MD	135	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	136	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	137	WARN_ON_ONCE(records_lost != 0);
	138	}
	139
4cfec15c	140	static int client_buffer_create(struct lttng_ust_lib_ring_buffer buf, void priv,
1d498196	141	int cpu, const char *name,
38fae1d3	142	struct lttng_ust_shm_handle *handle)
3d1fc7fd MD	143	{
	144	return 0;
	145	}
	146
4cfec15c	147	static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
1d498196	148	void *priv, int cpu,
38fae1d3	149	struct lttng_ust_shm_handle *handle)
3d1fc7fd MD	150	{
	151	}
	152
82b9bde8 JD	153	static const
	154	struct lttng_ust_client_lib_ring_buffer_client_cb client_cb = {
	155	.parent = {
	156	.ring_buffer_clock_read = client_ring_buffer_clock_read,
	157	.record_header_size = client_record_header_size,
	158	.subbuffer_header_size = client_packet_header_size,
	159	.buffer_begin = client_buffer_begin,
	160	.buffer_end = client_buffer_end,
	161	.buffer_create = client_buffer_create,
	162	.buffer_finalize = client_buffer_finalize,
	163	},
	164	};
	165
4cfec15c	166	static const struct lttng_ust_lib_ring_buffer_config client_config = {
3d1fc7fd MD	167	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	168	.cb.record_header_size = client_record_header_size,
	169	.cb.subbuffer_header_size = client_packet_header_size,
	170	.cb.buffer_begin = client_buffer_begin,
	171	.cb.buffer_end = client_buffer_end,
	172	.cb.buffer_create = client_buffer_create,
	173	.cb.buffer_finalize = client_buffer_finalize,
	174
	175	.tsc_bits = 0,
	176	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	177	.sync = RING_BUFFER_SYNC_GLOBAL,
	178	.mode = RING_BUFFER_MODE_TEMPLATE,
	179	.backend = RING_BUFFER_PAGE,
5d61a504	180	.output = RING_BUFFER_MMAP,
3d1fc7fd	181	.oops = RING_BUFFER_OOPS_CONSISTENCY,
5d61a504 MD	182	.ipi = RING_BUFFER_NO_IPI_BARRIER,
5d61a504 MD	183	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
c1fca457	184	.client_type = LTTNG_CLIENT_TYPE,
82b9bde8 JD	185
82b9bde8 JD	186	.cb_ptr = &client_cb.parent,
3d1fc7fd MD	187	};
3d1fc7fd MD	188
82b9bde8	189	const struct lttng_ust_client_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_cb;
c1fca457	190
3d1fc7fd	191	static
7dd08bec	192	struct lttng_channel _channel_create(const char name,
a3f61e7f	193	void *buf_addr,
3d1fc7fd MD	194	size_t subbuf_size, size_t num_subbuf,
3d1fc7fd MD	195	unsigned int switch_timer_interval,
193183fb	196	unsigned int read_timer_interval,
6ca18e66	197	unsigned char *uuid,
a9ff648c	198	uint32_t chan_id,
b2c5f61a MD	199	const int *stream_fds, int nr_stream_fds,
b2c5f61a MD	200	int64_t blocking_timeout)
3d1fc7fd	201	{
74d81a6c	202	struct lttng_channel chan_priv_init;
a3f61e7f	203	struct lttng_ust_shm_handle *handle;
74d81a6c MD	204	struct lttng_channel *lttng_chan;
74d81a6c MD	205	void *priv;
a3f61e7f	206
74d81a6c MD	207	memset(&chan_priv_init, 0, sizeof(chan_priv_init));
74d81a6c MD	208	memcpy(chan_priv_init.uuid, uuid, LTTNG_UST_UUID_LEN);
6ca18e66	209	chan_priv_init.id = chan_id;
a3f61e7f	210	handle = channel_create(&client_config, name,
8824f307 MD	211	&priv, __alignof__(struct lttng_channel),
8824f307 MD	212	sizeof(struct lttng_channel),
74d81a6c	213	&chan_priv_init,
a3f61e7f	214	buf_addr, subbuf_size, num_subbuf,
a9ff648c	215	switch_timer_interval, read_timer_interval,
b2c5f61a	216	stream_fds, nr_stream_fds, blocking_timeout);
a3f61e7f	217	if (!handle)
1b2c2540	218	return NULL;
7dd08bec MD	219	lttng_chan = priv;
7dd08bec MD	220	lttng_chan->handle = handle;
74d81a6c	221	lttng_chan->chan = shmp(handle, handle->chan);
7dd08bec	222	return lttng_chan;
3d1fc7fd MD	223	}
	224
	225	static
74d81a6c	226	void lttng_channel_destroy(struct lttng_channel *chan)
3d1fc7fd	227	{
74d81a6c	228	channel_destroy(chan->chan, chan->handle, 1);
3d1fc7fd MD	229	}
	230
	231	static
7dd08bec	232	int lttng_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
3d1fc7fd	233	{
a3492932 MD	234	int ret;
a3492932 MD	235
e56bb47c	236	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
a3492932 MD	237	if (ret)
	238	return ret;
	239	if (caa_likely(ctx->ctx_len
	240	>= sizeof(struct lttng_ust_lib_ring_buffer_ctx))) {
	241	if (lib_ring_buffer_backend_get_pages(&client_config, ctx,
	242	&ctx->backend_pages))
	243	return -EPERM;
	244	}
	245	return 0;
3d1fc7fd MD	246	}
	247
	248	static
7dd08bec	249	void lttng_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
3d1fc7fd MD	250	{
	251	lib_ring_buffer_commit(&client_config, ctx);
	252	}
	253
	254	static
7dd08bec	255	void lttng_event_write(struct lttng_ust_lib_ring_buffer_ctx ctx, const void src,
3d1fc7fd MD	256	size_t len)
	257	{
	258	lib_ring_buffer_write(&client_config, ctx, src, len);
	259	}
	260
	261	static
7dd08bec	262	size_t lttng_packet_avail_size(struct channel chan, struct lttng_ust_shm_handle handle)
3d1fc7fd MD	263	{
3d1fc7fd MD	264	unsigned long o_begin;
4cfec15c	265	struct lttng_ust_lib_ring_buffer *buf;
3d1fc7fd	266
1d498196	267	buf = shmp(handle, chan->backend.buf[0].shmp); /* Only for global buffer ! */
3d1fc7fd MD	268	o_begin = v_read(&client_config, &buf->offset);
	269	if (subbuf_offset(o_begin, chan) != 0) {
	270	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	271	} else {
	272	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	273	- sizeof(struct metadata_packet_header);
	274	}
	275	}
	276
9f3fdbc6	277	#if 0
3d1fc7fd	278	static
7dd08bec	279	wait_queue_head_t lttng_get_reader_wait_queue(struct channel chan)
3d1fc7fd MD	280	{
	281	return &chan->read_wait;
	282	}
	283
	284	static
7dd08bec	285	wait_queue_head_t lttng_get_hp_wait_queue(struct channel chan)
3d1fc7fd MD	286	{
	287	return &chan->hp_wait;
	288	}
9f3fdbc6	289	#endif //0
3d1fc7fd MD	290
3d1fc7fd MD	291	static
7dd08bec	292	int lttng_is_finalized(struct channel *chan)
3d1fc7fd MD	293	{
	294	return lib_ring_buffer_channel_is_finalized(chan);
	295	}
	296
	297	static
7dd08bec	298	int lttng_is_disabled(struct channel *chan)
3d1fc7fd MD	299	{
	300	return lib_ring_buffer_channel_is_disabled(chan);
	301	}
	302
43861eab	303	static
7dd08bec	304	int lttng_flush_buffer(struct channel chan, struct lttng_ust_shm_handle handle)
43861eab	305	{
4cfec15c	306	struct lttng_ust_lib_ring_buffer *buf;
74d81a6c MD	307	int shm_fd, wait_fd, wakeup_fd;
74d81a6c MD	308	uint64_t memory_map_size;
43861eab MD	309
43861eab MD	310	buf = channel_get_ring_buffer(&client_config, chan,
74d81a6c	311	0, handle, &shm_fd, &wait_fd, &wakeup_fd,
43861eab MD	312	&memory_map_size);
	313	lib_ring_buffer_switch(&client_config, buf,
	314	SWITCH_ACTIVE, handle);
	315	return 0;
	316	}
	317
7dd08bec	318	static struct lttng_transport lttng_relay_transport = {
818173b9	319	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
3d1fc7fd MD	320	.ops = {
3d1fc7fd MD	321	.channel_create = _channel_create,
7dd08bec	322	.channel_destroy = lttng_channel_destroy,
7dd08bec MD	323	.event_reserve = lttng_event_reserve,
	324	.event_commit = lttng_event_commit,
	325	.event_write = lttng_event_write,
	326	.packet_avail_size = lttng_packet_avail_size,
	327	//.get_reader_wait_queue = lttng_get_reader_wait_queue,
	328	//.get_hp_wait_queue = lttng_get_hp_wait_queue,
	329	.is_finalized = lttng_is_finalized,
	330	.is_disabled = lttng_is_disabled,
	331	.flush_buffer = lttng_flush_buffer,
3d1fc7fd	332	},
74d81a6c	333	.client_config = &client_config,
3d1fc7fd MD	334	};
3d1fc7fd MD	335
edaa1431	336	void RING_BUFFER_MODE_TEMPLATE_INIT(void)
3d1fc7fd	337	{
34a91bdb MD	338	DBG("LTT : ltt ring buffer client \"%s\" init\n",
34a91bdb MD	339	"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
7dd08bec	340	lttng_transport_register(&lttng_relay_transport);
3d1fc7fd MD	341	}
3d1fc7fd MD	342
edaa1431	343	void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
3d1fc7fd	344	{
34a91bdb MD	345	DBG("LTT : ltt ring buffer client \"%s\" exit\n",
34a91bdb MD	346	"relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap");
7dd08bec	347	lttng_transport_unregister(&lttng_relay_transport);
3d1fc7fd	348	}