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

/*
 * ltt-ring-buffer-client.h
 *
 * Copyright (C) 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * LTTng lib ring buffer client template.
 *
 * Dual LGPL v2.1/GPL v2 license.
 */

#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[16];		/* 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
u64 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 u64 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, u64 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);
	struct ltt_session *session = ltt_chan->session;

	header->magic = TSDL_MAGIC_NUMBER;
	memcpy(header->uuid, session->uuid, sizeof(session->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, u64 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 */
	records_lost += 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_config *LTTNG_CLIENT_CALLBACKS = &client_config;

static
struct ltt_channel *_channel_create(const char *name,
				struct ltt_channel *ltt_chan, void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval,
				int *shm_fd, int *wait_fd,
				uint64_t *memory_map_size)
{
	ltt_chan->handle = channel_create(&client_config, name, ltt_chan, buf_addr,
			      subbuf_size, num_subbuf, switch_timer_interval,
			      read_timer_interval, shm_fd, wait_fd,
			      memory_map_size);
	if (!ltt_chan->handle)
		return NULL;
	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, int *wait_fd,
					     uint64_t *memory_map_size)
{
	struct lttng_ust_lib_ring_buffer *buf;

	buf = channel_get_ring_buffer(&client_config, chan,
			0, handle, shm_fd, wait_fd, 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;
	uint64_t memory_map_size;

	buf = channel_get_ring_buffer(&client_config, chan,
			0, handle, &shm_fd, &wait_fd,
			&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
	1	/*
	2	* ltt-ring-buffer-client.h
	3	*
	4	* Copyright (C) 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	5	*
	6	* LTTng lib ring buffer client template.
	7	*
	8	* Dual LGPL v2.1/GPL v2 license.
	9	*/
	10
	11	#include <stdint.h>
	12	#include <lttng/ust-events.h>
	13	#include "lttng/bitfield.h"
	14	#include "ltt-tracer.h"
	15	#include "../libringbuffer/frontend_types.h"
	16
	17	struct metadata_packet_header {
	18	uint32_t magic; /* 0x75D11D57 */
	19	uint8_t uuid[16]; /* Unique Universal Identifier */
	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 */
	26	uint8_t major; /* CTF spec major version number */
	27	uint8_t minor; /* CTF spec minor version number */
	28	uint8_t header_end[0];
	29	};
	30
	31	struct metadata_record_header {
	32	uint8_t header_end[0]; /* End of header */
	33	};
	34
	35	static const struct lttng_ust_lib_ring_buffer_config client_config;
	36
	37	static inline
	38	u64 lib_ring_buffer_clock_read(struct channel *chan)
	39	{
	40	return 0;
	41	}
	42
	43	static inline
	44	unsigned char record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
	45	struct channel *chan, size_t offset,
	46	size_t *pre_header_padding,
	47	struct lttng_ust_lib_ring_buffer_ctx *ctx)
	48	{
	49	return 0;
	50	}
	51
	52	#include "../libringbuffer/api.h"
	53
	54	static u64 client_ring_buffer_clock_read(struct channel *chan)
	55	{
	56	return 0;
	57	}
	58
	59	static
	60	size_t client_record_header_size(const struct lttng_ust_lib_ring_buffer_config *config,
	61	struct channel *chan, size_t offset,
	62	size_t *pre_header_padding,
	63	struct lttng_ust_lib_ring_buffer_ctx *ctx)
	64	{
	65	return 0;
	66	}
	67
	68	/**
	69	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	70	*
	71	* Return header size without padding after the structure. Don't use packed
	72	* structure because gcc generates inefficient code on some architectures
	73	* (powerpc, mips..)
	74	*/
	75	static size_t client_packet_header_size(void)
	76	{
	77	return offsetof(struct metadata_packet_header, header_end);
	78	}
	79
	80	static void client_buffer_begin(struct lttng_ust_lib_ring_buffer *buf, u64 tsc,
	81	unsigned int subbuf_idx,
	82	struct lttng_ust_shm_handle *handle)
	83	{
	84	struct channel *chan = shmp(handle, buf->backend.chan);
	85	struct metadata_packet_header *header =
	86	(struct metadata_packet_header *)
	87	lib_ring_buffer_offset_address(&buf->backend,
	88	subbuf_idx * chan->backend.subbuf_size,
	89	handle);
	90	struct ltt_channel *ltt_chan = channel_get_private(chan);
	91	struct ltt_session *session = ltt_chan->session;
	92
	93	header->magic = TSDL_MAGIC_NUMBER;
	94	memcpy(header->uuid, session->uuid, sizeof(session->uuid));
	95	header->checksum = 0; /* 0 if unused */
	96	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	97	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	98	header->compression_scheme = 0; /* 0 if unused */
	99	header->encryption_scheme = 0; /* 0 if unused */
	100	header->checksum_scheme = 0; /* 0 if unused */
	101	header->major = CTF_SPEC_MAJOR;
	102	header->minor = CTF_SPEC_MINOR;
	103
	104	}
	105
	106	/*
	107	* offset is assumed to never be 0 here : never deliver a completely empty
	108	* subbuffer. data_size is between 1 and subbuf_size.
	109	*/
	110	static void client_buffer_end(struct lttng_ust_lib_ring_buffer *buf, u64 tsc,
	111	unsigned int subbuf_idx, unsigned long data_size,
	112	struct lttng_ust_shm_handle *handle)
	113	{
	114	struct channel *chan = shmp(handle, buf->backend.chan);
	115	struct metadata_packet_header *header =
	116	(struct metadata_packet_header *)
	117	lib_ring_buffer_offset_address(&buf->backend,
	118	subbuf_idx * chan->backend.subbuf_size,
	119	handle);
	120	unsigned long records_lost = 0;
	121
	122	header->content_size = data_size * CHAR_BIT; /* in bits */
	123	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
	124	records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf);
	125	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	126	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	127	WARN_ON_ONCE(records_lost != 0);
	128	}
	129
	130	static int client_buffer_create(struct lttng_ust_lib_ring_buffer buf, void priv,
	131	int cpu, const char *name,
	132	struct lttng_ust_shm_handle *handle)
	133	{
	134	return 0;
	135	}
	136
	137	static void client_buffer_finalize(struct lttng_ust_lib_ring_buffer *buf,
	138	void *priv, int cpu,
	139	struct lttng_ust_shm_handle *handle)
	140	{
	141	}
	142
	143	static const struct lttng_ust_lib_ring_buffer_config client_config = {
	144	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	145	.cb.record_header_size = client_record_header_size,
	146	.cb.subbuffer_header_size = client_packet_header_size,
	147	.cb.buffer_begin = client_buffer_begin,
	148	.cb.buffer_end = client_buffer_end,
	149	.cb.buffer_create = client_buffer_create,
	150	.cb.buffer_finalize = client_buffer_finalize,
	151
	152	.tsc_bits = 0,
	153	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	154	.sync = RING_BUFFER_SYNC_GLOBAL,
	155	.mode = RING_BUFFER_MODE_TEMPLATE,
	156	.backend = RING_BUFFER_PAGE,
	157	.output = RING_BUFFER_MMAP,
	158	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	159	.ipi = RING_BUFFER_NO_IPI_BARRIER,
	160	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
	161	.client_type = LTTNG_CLIENT_TYPE,
	162	};
	163
	164	const struct lttng_ust_lib_ring_buffer_config *LTTNG_CLIENT_CALLBACKS = &client_config;
	165
	166	static
	167	struct ltt_channel _channel_create(const char name,
	168	struct ltt_channel ltt_chan, void buf_addr,
	169	size_t subbuf_size, size_t num_subbuf,
	170	unsigned int switch_timer_interval,
	171	unsigned int read_timer_interval,
	172	int shm_fd, int wait_fd,
	173	uint64_t *memory_map_size)
	174	{
	175	ltt_chan->handle = channel_create(&client_config, name, ltt_chan, buf_addr,
	176	subbuf_size, num_subbuf, switch_timer_interval,
	177	read_timer_interval, shm_fd, wait_fd,
	178	memory_map_size);
	179	if (!ltt_chan->handle)
	180	return NULL;
	181	ltt_chan->chan = shmp(ltt_chan->handle, ltt_chan->handle->chan);
	182	return ltt_chan;
	183	}
	184
	185	static
	186	void ltt_channel_destroy(struct ltt_channel *ltt_chan)
	187	{
	188	channel_destroy(ltt_chan->chan, ltt_chan->handle, 0);
	189	}
	190
	191	static
	192	struct lttng_ust_lib_ring_buffer ltt_buffer_read_open(struct channel chan,
	193	struct lttng_ust_shm_handle *handle,
	194	int shm_fd, int wait_fd,
	195	uint64_t *memory_map_size)
	196	{
	197	struct lttng_ust_lib_ring_buffer *buf;
	198
	199	buf = channel_get_ring_buffer(&client_config, chan,
	200	0, handle, shm_fd, wait_fd, memory_map_size);
	201	if (!lib_ring_buffer_open_read(buf, handle, 0))
	202	return buf;
	203	return NULL;
	204	}
	205
	206	static
	207	void ltt_buffer_read_close(struct lttng_ust_lib_ring_buffer *buf,
	208	struct lttng_ust_shm_handle *handle)
	209	{
	210	lib_ring_buffer_release_read(buf, handle, 0);
	211	}
	212
	213	static
	214	int ltt_event_reserve(struct lttng_ust_lib_ring_buffer_ctx *ctx, uint32_t event_id)
	215	{
	216	return lib_ring_buffer_reserve(&client_config, ctx);
	217	}
	218
	219	static
	220	void ltt_event_commit(struct lttng_ust_lib_ring_buffer_ctx *ctx)
	221	{
	222	lib_ring_buffer_commit(&client_config, ctx);
	223	}
	224
	225	static
	226	void ltt_event_write(struct lttng_ust_lib_ring_buffer_ctx ctx, const void src,
	227	size_t len)
	228	{
	229	lib_ring_buffer_write(&client_config, ctx, src, len);
	230	}
	231
	232	static
	233	size_t ltt_packet_avail_size(struct channel chan, struct lttng_ust_shm_handle handle)
	234
	235	{
	236	unsigned long o_begin;
	237	struct lttng_ust_lib_ring_buffer *buf;
	238
	239	buf = shmp(handle, chan->backend.buf[0].shmp); /* Only for global buffer ! */
	240	o_begin = v_read(&client_config, &buf->offset);
	241	if (subbuf_offset(o_begin, chan) != 0) {
	242	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	243	} else {
	244	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	245	- sizeof(struct metadata_packet_header);
	246	}
	247	}
	248
	249	#if 0
	250	static
	251	wait_queue_head_t ltt_get_reader_wait_queue(struct channel chan)
	252	{
	253	return &chan->read_wait;
	254	}
	255
	256	static
	257	wait_queue_head_t ltt_get_hp_wait_queue(struct channel chan)
	258	{
	259	return &chan->hp_wait;
	260	}
	261	#endif //0
	262
	263	static
	264	int ltt_is_finalized(struct channel *chan)
	265	{
	266	return lib_ring_buffer_channel_is_finalized(chan);
	267	}
	268
	269	static
	270	int ltt_is_disabled(struct channel *chan)
	271	{
	272	return lib_ring_buffer_channel_is_disabled(chan);
	273	}
	274
	275	static
	276	int ltt_flush_buffer(struct channel chan, struct lttng_ust_shm_handle handle)
	277	{
	278	struct lttng_ust_lib_ring_buffer *buf;
	279	int shm_fd, wait_fd;
	280	uint64_t memory_map_size;
	281
	282	buf = channel_get_ring_buffer(&client_config, chan,
	283	0, handle, &shm_fd, &wait_fd,
	284	&memory_map_size);
	285	lib_ring_buffer_switch(&client_config, buf,
	286	SWITCH_ACTIVE, handle);
	287	return 0;
	288	}
	289
	290	static struct ltt_transport ltt_relay_transport = {
	291	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING "-mmap",
	292	.ops = {
	293	.channel_create = _channel_create,
	294	.channel_destroy = ltt_channel_destroy,
	295	.buffer_read_open = ltt_buffer_read_open,
	296	.buffer_read_close = ltt_buffer_read_close,
	297	.event_reserve = ltt_event_reserve,
	298	.event_commit = ltt_event_commit,
	299	.event_write = ltt_event_write,
	300	.packet_avail_size = ltt_packet_avail_size,
	301	//.get_reader_wait_queue = ltt_get_reader_wait_queue,
	302	//.get_hp_wait_queue = ltt_get_hp_wait_queue,
	303	.is_finalized = ltt_is_finalized,
	304	.is_disabled = ltt_is_disabled,
	305	.flush_buffer = ltt_flush_buffer,
	306	},
	307	};
	308
	309	void RING_BUFFER_MODE_TEMPLATE_INIT(void)
	310	{
	311	DBG("LTT : ltt ring buffer client init\n");
	312	ltt_transport_register(&ltt_relay_transport);
	313	}
	314
	315	void RING_BUFFER_MODE_TEMPLATE_EXIT(void)
	316	{
	317	DBG("LTT : ltt ring buffer client exit\n");
	318	ltt_transport_unregister(&ltt_relay_transport);
	319	}