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

/*
 * ltt-ring-buffer-client.h
 *
 * LTTng lib ring buffer client template.
 *
 * 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 <stdint.h>
#include <lttng/ust-events.h>
#include "lttng/bitfield.h"
#include "ltt-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
unsigned char 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)
{
	return 0;
}

#include "../libringbuffer/api.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)
{
	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 ltt_channel *ltt_chan = channel_get_private(chan);

	header->magic = TSDL_MAGIC_NUMBER;
	memcpy(header->uuid, ltt_chan->uuid, sizeof(ltt_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;

	header->content_size = data_size * CHAR_BIT;		/* in bits */
	header->packet_size = 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_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,
};

const struct lttng_ust_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_config.cb;

static
struct ltt_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,
				int **shm_fd, char **shm_path,
				int **wait_fd, char **wait_pipe_path,
				uint64_t **memory_map_size,
				struct ltt_channel *chan_priv_init)
{
	void *priv;
	struct ltt_channel *ltt_chan = NULL;
	struct lttng_ust_shm_handle *handle;

	handle = channel_create(&client_config, name,
			&priv, __alignof__(*ltt_chan), sizeof(*ltt_chan),
			chan_priv_init,
			buf_addr, subbuf_size, num_subbuf,
			switch_timer_interval, read_timer_interval,
			shm_fd, shm_path, wait_fd, wait_pipe_path,
			memory_map_size);
	if (!handle)
		return NULL;
	ltt_chan = priv;
	ltt_chan->handle = handle;
	ltt_chan->chan = shmp(ltt_chan->handle, ltt_chan->handle->chan);
	return ltt_chan;
}

static
void ltt_channel_destroy(struct ltt_channel *ltt_chan)
{
	channel_destroy(ltt_chan->chan, ltt_chan->handle, 0);
}

static
struct lttng_ust_lib_ring_buffer *ltt_buffer_read_open(struct channel *chan,
						       struct lttng_ust_shm_handle *handle,
						       int **shm_fd, char **shm_path,
						       int **wait_fd, char **wait_pipe_path,
						       uint64_t **memory_map_size)
{
	struct lttng_ust_lib_ring_buffer *buf;

	buf = channel_get_ring_buffer(&client_config, chan,
				      0, handle, shm_fd, shm_path,
				      wait_fd, wait_pipe_path,
				      memory_map_size);
	if (!lib_ring_buffer_open_read(buf, handle, 0))
		return buf;
	return NULL;
}

static
void ltt_buffer_read_close(struct lttng_ust_lib_ring_buffer *buf,
			   struct lttng_ust_shm_handle *handle)
{
	lib_ring_buffer_release_read(buf, handle, 0);
}

static
int ltt_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
{
	return lib_ring_buffer_reserve(&client_config, ctx);
}

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

static
void ltt_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 ltt_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 *ltt_get_reader_wait_queue(struct channel *chan)
{
	return &chan->read_wait;
}

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

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

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

static
int ltt_flush_buffer(struct channel *chan, struct lttng_ust_shm_handle *handle)
{
	struct lttng_ust_lib_ring_buffer *buf;
	int *shm_fd, *wait_fd;
	char *shm_path, *wait_pipe_path;
	uint64_t *memory_map_size;

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

static struct ltt_transport ltt_relay_transport = {
	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
	.ops = {
		.channel_create = _channel_create,
		.channel_destroy = ltt_channel_destroy,
		.buffer_read_open = ltt_buffer_read_open,
		.buffer_read_close = ltt_buffer_read_close,
		.event_reserve = ltt_event_reserve,
		.event_commit = ltt_event_commit,
		.event_write = ltt_event_write,
		.packet_avail_size = ltt_packet_avail_size,
		//.get_reader_wait_queue = ltt_get_reader_wait_queue,
		//.get_hp_wait_queue = ltt_get_hp_wait_queue,
		.is_finalized = ltt_is_finalized,
		.is_disabled = ltt_is_disabled,
		.flush_buffer = ltt_flush_buffer,
	},
};

void RING_BUFFER_MODE_TEMPLATE_INIT(void)
{
	DBG("LTT : ltt ring buffer client init\n");
	ltt_transport_register(&ltt_relay_transport);
}

void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
{
	DBG("LTT : ltt ring buffer client exit\n");
	ltt_transport_unregister(&ltt_relay_transport);
}
Commit	Line	Data
3d1fc7fd MD	1	/*
	2	* ltt-ring-buffer-client.h
	3	*
3d1fc7fd MD	4	* LTTng lib ring buffer client template.
3d1fc7fd MD	5	*
e92f3e28 MD	6	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
	10	* License as published by the Free Software Foundation; only
	11	* version 2.1 of the License.
	12	*
	13	* This library 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 GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
3d1fc7fd MD	21	*/
3d1fc7fd MD	22
9f3fdbc6	23	#include <stdint.h>
4318ae1b MD	24	#include <lttng/ust-events.h>
4318ae1b MD	25	#include "lttng/bitfield.h"
3d1fc7fd	26	#include "ltt-tracer.h"
9f3fdbc6	27	#include "../libringbuffer/frontend_types.h"
3d1fc7fd MD	28
	29	struct metadata_packet_header {
	30	uint32_t magic; /* 0x75D11D57 */
7e50e956	31	uint8_t uuid[LTTNG_UST_UUID_LEN]; /* Unique Universal Identifier */
3d1fc7fd MD	32	uint32_t checksum; /* 0 if unused */
	33	uint32_t content_size; /* in bits */
	34	uint32_t packet_size; /* in bits */
	35	uint8_t compression_scheme; /* 0 if unused */
	36	uint8_t encryption_scheme; /* 0 if unused */
	37	uint8_t checksum_scheme; /* 0 if unused */
8a98a75d MD	38	uint8_t major; /* CTF spec major version number */
8a98a75d MD	39	uint8_t minor; /* CTF spec minor version number */
3d1fc7fd MD	40	uint8_t header_end[0];
	41	};
	42
	43	struct metadata_record_header {
	44	uint8_t header_end[0]; /* End of header */
	45	};
	46
4cfec15c	47	static const struct lttng_ust_lib_ring_buffer_config client_config;
3d1fc7fd	48
23c8854a	49	static inline uint64_t lib_ring_buffer_clock_read(struct channel *chan)
3d1fc7fd MD	50	{
	51	return 0;
	52	}
	53
	54	static inline
4cfec15c	55	unsigned char record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
3d1fc7fd MD	56	struct channel *chan, size_t offset,
3d1fc7fd MD	57	size_t *pre_header_padding,
4cfec15c	58	struct lttng_ust_lib_ring_buffer_ctx *ctx)
3d1fc7fd MD	59	{
	60	return 0;
	61	}
	62
9f3fdbc6	63	#include "../libringbuffer/api.h"
3d1fc7fd	64
23c8854a	65	static uint64_t client_ring_buffer_clock_read(struct channel *chan)
3d1fc7fd MD	66	{
	67	return 0;
	68	}
	69
	70	static
4cfec15c	71	size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
3d1fc7fd MD	72	struct channel *chan, size_t offset,
3d1fc7fd MD	73	size_t *pre_header_padding,
4cfec15c	74	struct lttng_ust_lib_ring_buffer_ctx *ctx)
3d1fc7fd MD	75	{
	76	return 0;
	77	}
	78
	79	/**
	80	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	81	*
	82	* Return header size without padding after the structure. Don't use packed
	83	* structure because gcc generates inefficient code on some architectures
	84	* (powerpc, mips..)
	85	*/
	86	static size_t client_packet_header_size(void)
	87	{
	88	return offsetof(struct metadata_packet_header, header_end);
	89	}
	90
23c8854a	91	static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
1d498196	92	unsigned int subbuf_idx,
38fae1d3	93	struct lttng_ust_shm_handle *handle)
3d1fc7fd	94	{
1d498196	95	struct channel *chan = shmp(handle, buf->backend.chan);
3d1fc7fd MD	96	struct metadata_packet_header *header =
	97	(struct metadata_packet_header *)
	98	lib_ring_buffer_offset_address(&buf->backend,
1d498196 MD	99	subbuf_idx * chan->backend.subbuf_size,
1d498196 MD	100	handle);
3d1fc7fd	101	struct ltt_channel *ltt_chan = channel_get_private(chan);
3d1fc7fd MD	102
3d1fc7fd MD	103	header->magic = TSDL_MAGIC_NUMBER;
a3f61e7f	104	memcpy(header->uuid, ltt_chan->uuid, sizeof(ltt_chan->uuid));
3d1fc7fd MD	105	header->checksum = 0; /* 0 if unused */
	106	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	107	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	108	header->compression_scheme = 0; /* 0 if unused */
	109	header->encryption_scheme = 0; /* 0 if unused */
	110	header->checksum_scheme = 0; /* 0 if unused */
8a98a75d MD	111	header->major = CTF_SPEC_MAJOR;
	112	header->minor = CTF_SPEC_MINOR;
	113
3d1fc7fd MD	114	}
	115
	116	/*
	117	* offset is assumed to never be 0 here : never deliver a completely empty
	118	* subbuffer. data_size is between 1 and subbuf_size.
	119	*/
23c8854a	120	static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, uint64_t tsc,
1d498196	121	unsigned int subbuf_idx, unsigned long data_size,
38fae1d3	122	struct lttng_ust_shm_handle *handle)
3d1fc7fd	123	{
1d498196	124	struct channel *chan = shmp(handle, buf->backend.chan);
3d1fc7fd MD	125	struct metadata_packet_header *header =
	126	(struct metadata_packet_header *)
	127	lib_ring_buffer_offset_address(&buf->backend,
1d498196 MD	128	subbuf_idx * chan->backend.subbuf_size,
1d498196 MD	129	handle);
3d1fc7fd MD	130	unsigned long records_lost = 0;
	131
	132	header->content_size = data_size * CHAR_BIT; /* in bits */
	133	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
04489ab4 MD	134	/*
	135	* We do not care about the records lost count, because the metadata
	136	* channel waits and retry.
	137	*/
	138	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
3d1fc7fd MD	139	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	140	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	141	WARN_ON_ONCE(records_lost != 0);
	142	}
	143
4cfec15c	144	static int client_buffer_create(struct lttng_ust_lib_ring_buffer buf, void priv,
1d498196	145	int cpu, const char *name,
38fae1d3	146	struct lttng_ust_shm_handle *handle)
3d1fc7fd MD	147	{
	148	return 0;
	149	}
	150
4cfec15c	151	static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
1d498196	152	void *priv, int cpu,
38fae1d3	153	struct lttng_ust_shm_handle *handle)
3d1fc7fd MD	154	{
	155	}
	156
4cfec15c	157	static const struct lttng_ust_lib_ring_buffer_config client_config = {
3d1fc7fd MD	158	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	159	.cb.record_header_size = client_record_header_size,
	160	.cb.subbuffer_header_size = client_packet_header_size,
	161	.cb.buffer_begin = client_buffer_begin,
	162	.cb.buffer_end = client_buffer_end,
	163	.cb.buffer_create = client_buffer_create,
	164	.cb.buffer_finalize = client_buffer_finalize,
	165
	166	.tsc_bits = 0,
	167	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	168	.sync = RING_BUFFER_SYNC_GLOBAL,
	169	.mode = RING_BUFFER_MODE_TEMPLATE,
	170	.backend = RING_BUFFER_PAGE,
5d61a504	171	.output = RING_BUFFER_MMAP,
3d1fc7fd	172	.oops = RING_BUFFER_OOPS_CONSISTENCY,
5d61a504 MD	173	.ipi = RING_BUFFER_NO_IPI_BARRIER,
5d61a504 MD	174	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
c1fca457	175	.client_type = LTTNG_CLIENT_TYPE,
3d1fc7fd MD	176	};
3d1fc7fd MD	177
7a784989	178	const struct lttng_ust_lib_ring_buffer_client_cb *LTTNG_CLIENT_CALLBACKS = &client_config.cb;
c1fca457	179
3d1fc7fd	180	static
1d498196	181	struct ltt_channel _channel_create(const char name,
a3f61e7f	182	void *buf_addr,
3d1fc7fd MD	183	size_t subbuf_size, size_t num_subbuf,
3d1fc7fd MD	184	unsigned int switch_timer_interval,
193183fb	185	unsigned int read_timer_interval,
bf5ff35e CB	186	int shm_fd, char shm_path,
bf5ff35e CB	187	int wait_fd, char wait_pipe_path,
ef9ff354	188	uint64_t **memory_map_size,
d028eddb	189	struct ltt_channel *chan_priv_init)
3d1fc7fd	190	{
a3f61e7f MD	191	void *priv;
	192	struct ltt_channel *ltt_chan = NULL;
	193	struct lttng_ust_shm_handle *handle;
	194
	195	handle = channel_create(&client_config, name,
	196	&priv, __alignof__(ltt_chan), sizeof(ltt_chan),
d028eddb	197	chan_priv_init,
a3f61e7f MD	198	buf_addr, subbuf_size, num_subbuf,
a3f61e7f MD	199	switch_timer_interval, read_timer_interval,
bf5ff35e CB	200	shm_fd, shm_path, wait_fd, wait_pipe_path,
bf5ff35e CB	201	memory_map_size);
a3f61e7f	202	if (!handle)
1b2c2540	203	return NULL;
a3f61e7f MD	204	ltt_chan = priv;
a3f61e7f MD	205	ltt_chan->handle = handle;
1b2c2540	206	ltt_chan->chan = shmp(ltt_chan->handle, ltt_chan->handle->chan);
1d498196	207	return ltt_chan;
3d1fc7fd MD	208	}
	209
	210	static
1d498196	211	void ltt_channel_destroy(struct ltt_channel *ltt_chan)
3d1fc7fd	212	{
824f40b8	213	channel_destroy(ltt_chan->chan, ltt_chan->handle, 0);
3d1fc7fd MD	214	}
	215
	216	static
4cfec15c	217	struct lttng_ust_lib_ring_buffer ltt_buffer_read_open(struct channel chan,
bf5ff35e CB	218	struct lttng_ust_shm_handle *handle,
	219	int shm_fd, char shm_path,
	220	int wait_fd, char wait_pipe_path,
	221	uint64_t **memory_map_size)
3d1fc7fd	222	{
4cfec15c	223	struct lttng_ust_lib_ring_buffer *buf;
3d1fc7fd	224
381c0f1e	225	buf = channel_get_ring_buffer(&client_config, chan,
bf5ff35e CB	226	0, handle, shm_fd, shm_path,
	227	wait_fd, wait_pipe_path,
	228	memory_map_size);
824f40b8	229	if (!lib_ring_buffer_open_read(buf, handle, 0))
3d1fc7fd MD	230	return buf;
	231	return NULL;
	232	}
	233
	234	static
4cfec15c	235	void ltt_buffer_read_close(struct lttng_ust_lib_ring_buffer *buf,
38fae1d3	236	struct lttng_ust_shm_handle *handle)
3d1fc7fd	237	{
824f40b8	238	lib_ring_buffer_release_read(buf, handle, 0);
3d1fc7fd MD	239	}
	240
	241	static
4cfec15c	242	int ltt_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
3d1fc7fd MD	243	{
	244	return lib_ring_buffer_reserve(&client_config, ctx);
	245	}
	246
	247	static
4cfec15c	248	void ltt_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
4cfec15c	254	void ltt_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
38fae1d3	261	size_t ltt_packet_avail_size(struct channel chan, struct lttng_ust_shm_handle handle)
3d1fc7fd MD	262
	263	{
	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 MD	278	static
	279	wait_queue_head_t ltt_get_reader_wait_queue(struct channel chan)
	280	{
	281	return &chan->read_wait;
	282	}
	283
	284	static
	285	wait_queue_head_t ltt_get_hp_wait_queue(struct channel chan)
	286	{
	287	return &chan->hp_wait;
	288	}
9f3fdbc6	289	#endif //0
3d1fc7fd MD	290
	291	static
	292	int ltt_is_finalized(struct channel *chan)
	293	{
	294	return lib_ring_buffer_channel_is_finalized(chan);
	295	}
	296
	297	static
	298	int ltt_is_disabled(struct channel *chan)
	299	{
	300	return lib_ring_buffer_channel_is_disabled(chan);
	301	}
	302
43861eab	303	static
38fae1d3	304	int ltt_flush_buffer(struct channel chan, struct lttng_ust_shm_handle handle)
43861eab	305	{
4cfec15c	306	struct lttng_ust_lib_ring_buffer *buf;
ef9ff354	307	int shm_fd, wait_fd;
bf5ff35e	308	char shm_path, wait_pipe_path;
ef9ff354	309	uint64_t *memory_map_size;
43861eab MD	310
43861eab MD	311	buf = channel_get_ring_buffer(&client_config, chan,
bf5ff35e CB	312	0, handle, &shm_fd, &shm_path,
	313	&wait_fd, &wait_pipe_path,
	314	&memory_map_size);
43861eab MD	315	lib_ring_buffer_switch(&client_config, buf,
	316	SWITCH_ACTIVE, handle);
	317	return 0;
	318	}
	319
3d1fc7fd	320	static struct ltt_transport ltt_relay_transport = {
818173b9	321	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
3d1fc7fd MD	322	.ops = {
	323	.channel_create = _channel_create,
	324	.channel_destroy = ltt_channel_destroy,
	325	.buffer_read_open = ltt_buffer_read_open,
	326	.buffer_read_close = ltt_buffer_read_close,
	327	.event_reserve = ltt_event_reserve,
	328	.event_commit = ltt_event_commit,
	329	.event_write = ltt_event_write,
	330	.packet_avail_size = ltt_packet_avail_size,
9f3fdbc6 MD	331	//.get_reader_wait_queue = ltt_get_reader_wait_queue,
9f3fdbc6 MD	332	//.get_hp_wait_queue = ltt_get_hp_wait_queue,
3d1fc7fd MD	333	.is_finalized = ltt_is_finalized,
3d1fc7fd MD	334	.is_disabled = ltt_is_disabled,
43d330a4	335	.flush_buffer = ltt_flush_buffer,
3d1fc7fd MD	336	},
	337	};
	338
edaa1431	339	void RING_BUFFER_MODE_TEMPLATE_INIT(void)
3d1fc7fd	340	{
18c1cd87	341	DBG("LTT : ltt ring buffer client init\n");
3d1fc7fd	342	ltt_transport_register(&ltt_relay_transport);
3d1fc7fd MD	343	}
3d1fc7fd MD	344
edaa1431	345	void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
3d1fc7fd	346	{
18c1cd87	347	DBG("LTT : ltt ring buffer client exit\n");
3d1fc7fd MD	348	ltt_transport_unregister(&ltt_relay_transport);
3d1fc7fd MD	349	}