[lttng-ust.git] / libust / ltt-ring-buffer-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 "ust/bitfield.h"
#include "ust/clock.h"
#include "ltt-events.h"
#include "ltt-tracer.h"
#include "../libringbuffer/frontend_types.h"

/*
 * Keep the natural field alignment for _each field_ within this structure if
 * you ever add/remove a field from this header. Packed attribute is not used
 * because gcc generates poor code on at least powerpc and mips. Don't ever
 * let gcc add padding between the structure elements.
 */

struct packet_header {
	/* Trace packet header */
	uint32_t magic;			/*
					 * Trace magic number.
					 * contains endianness information.
					 */
	uint8_t uuid[16];
	uint32_t stream_id;

	struct {
		/* Stream packet context */
		uint64_t timestamp_begin;	/* Cycle count at subbuffer start */
		uint64_t timestamp_end;		/* Cycle count at subbuffer end */
		uint32_t events_discarded;	/*
						 * Events lost in this subbuffer since
						 * the beginning of the trace.
						 * (may overflow)
						 */
		uint32_t content_size;		/* Size of data in subbuffer */
		uint32_t packet_size;		/* Subbuffer size (include padding) */
		uint32_t cpu_id;		/* CPU id associated with stream */
		uint8_t header_end;		/* End of header */
	} ctx;
};


static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
{
	return trace_clock_read64();
}

static inline
size_t ctx_get_size(size_t offset, struct lttng_ctx *ctx)
{
	int i;
	size_t orig_offset = offset;

	if (likely(!ctx))
		return 0;
	for (i = 0; i < ctx->nr_fields; i++)
		offset += ctx->fields[i].get_size(offset);
	return offset - orig_offset;
}

static inline
void ctx_record(struct lib_ring_buffer_ctx *bufctx,
		struct ltt_channel *chan,
		struct lttng_ctx *ctx)
{
	int i;

	if (likely(!ctx))
		return;
	for (i = 0; i < ctx->nr_fields; i++)
		ctx->fields[i].record(&ctx->fields[i], bufctx, chan);
}

/*
 * record_header_size - Calculate the header size and padding necessary.
 * @config: ring buffer instance configuration
 * @chan: channel
 * @offset: offset in the write buffer
 * @pre_header_padding: padding to add before the header (output)
 * @ctx: reservation context
 *
 * Returns the event header size (including padding).
 *
 * The payload must itself determine its own alignment from the biggest type it
 * contains.
 */
static __inline__
unsigned char 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)
{
	struct ltt_channel *ltt_chan = channel_get_private(chan);
	struct ltt_event *event = ctx->priv;
	size_t orig_offset = offset;
	size_t padding;

	switch (ltt_chan->header_type) {
	case 1:	/* compact */
		padding = lib_ring_buffer_align(offset, ltt_alignof(uint32_t));
		offset += padding;
		if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTT_RFLAG_EXTENDED))) {
			offset += sizeof(uint32_t);	/* id and timestamp */
		} else {
			/* Minimum space taken by 5-bit id */
			offset += sizeof(uint8_t);
			/* Align extended struct on largest member */
			offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
			offset += sizeof(uint32_t);	/* id */
			offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
			offset += sizeof(uint64_t);	/* timestamp */
		}
		break;
	case 2:	/* large */
		padding = lib_ring_buffer_align(offset, ltt_alignof(uint16_t));
		offset += padding;
		offset += sizeof(uint16_t);
		if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTT_RFLAG_EXTENDED))) {
			offset += lib_ring_buffer_align(offset, ltt_alignof(uint32_t));
			offset += sizeof(uint32_t);	/* timestamp */
		} else {
			/* Align extended struct on largest member */
			offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
			offset += sizeof(uint32_t);	/* id */
			offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
			offset += sizeof(uint64_t);	/* timestamp */
		}
		break;
	default:
		padding = 0;
		WARN_ON_ONCE(1);
	}
	offset += ctx_get_size(offset, event->ctx);
	offset += ctx_get_size(offset, ltt_chan->ctx);

	*pre_header_padding = padding;
	return offset - orig_offset;
}

#include "../libringbuffer/api.h"

static
void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
				 struct lib_ring_buffer_ctx *ctx,
				 uint32_t event_id);

/*
 * ltt_write_event_header
 *
 * Writes the event header to the offset (already aligned on 32-bits).
 *
 * @config: ring buffer instance configuration
 * @ctx: reservation context
 * @event_id: event ID
 */
static __inline__
void ltt_write_event_header(const struct lib_ring_buffer_config *config,
			    struct lib_ring_buffer_ctx *ctx,
			    uint32_t event_id)
{
	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	struct ltt_event *event = ctx->priv;

	if (unlikely(ctx->rflags))
		goto slow_path;

	switch (ltt_chan->header_type) {
	case 1:	/* compact */
	{
		uint32_t id_time = 0;

		bt_bitfield_write(&id_time, uint32_t, 0, 5, event_id);
		bt_bitfield_write(&id_time, uint32_t, 5, 27, ctx->tsc);
		lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
		break;
	}
	case 2:	/* large */
	{
		uint32_t timestamp = (uint32_t) ctx->tsc;
		uint16_t id = event_id;

		lib_ring_buffer_write(config, ctx, &id, sizeof(id));
		lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
		lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
		break;
	}
	default:
		WARN_ON_ONCE(1);
	}

	ctx_record(ctx, ltt_chan, event->ctx);
	ctx_record(ctx, ltt_chan, ltt_chan->ctx);

	return;

slow_path:
	ltt_write_event_header_slow(config, ctx, event_id);
}

static
void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
				 struct lib_ring_buffer_ctx *ctx,
				 uint32_t event_id)
{
	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	struct ltt_event *event = ctx->priv;

	switch (ltt_chan->header_type) {
	case 1:	/* compact */
		if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTT_RFLAG_EXTENDED))) {
			uint32_t id_time = 0;

			bt_bitfield_write(&id_time, uint32_t, 0, 5, event_id);
			bt_bitfield_write(&id_time, uint32_t, 5, 27, ctx->tsc);
			lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
		} else {
			uint8_t id = 0;
			uint64_t timestamp = ctx->tsc;

			bt_bitfield_write(&id, uint8_t, 0, 5, 31);
			lib_ring_buffer_write(config, ctx, &id, sizeof(id));
			/* Align extended struct on largest member */
			lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
			lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
			lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
			lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
		}
		break;
	case 2:	/* large */
	{
		if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC | LTT_RFLAG_EXTENDED))) {
			uint32_t timestamp = (uint32_t) ctx->tsc;
			uint16_t id = event_id;

			lib_ring_buffer_write(config, ctx, &id, sizeof(id));
			lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
			lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
		} else {
			uint16_t id = 65535;
			uint64_t timestamp = ctx->tsc;

			lib_ring_buffer_write(config, ctx, &id, sizeof(id));
			/* Align extended struct on largest member */
			lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
			lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
			lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
			lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
		}
		break;
	}
	default:
		WARN_ON_ONCE(1);
	}
	ctx_record(ctx, ltt_chan, event->ctx);
	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
}

static const struct lib_ring_buffer_config client_config;

static u64 client_ring_buffer_clock_read(struct channel *chan)
{
	return lib_ring_buffer_clock_read(chan);
}

static
size_t client_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)
{
	return record_header_size(config, chan, offset,
				  pre_header_padding, ctx);
}

/**
 * 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 packet_header, ctx.header_end);
}

static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
				unsigned int subbuf_idx)
{
	struct channel *chan = shmp(buf->backend.chan);
	struct packet_header *header =
		(struct packet_header *)
			lib_ring_buffer_offset_address(&buf->backend,
				subbuf_idx * chan->backend.subbuf_size);
	struct ltt_channel *ltt_chan = channel_get_private(chan);
	struct ltt_session *session = ltt_chan->session;

	header->magic = CTF_MAGIC_NUMBER;
	memcpy(header->uuid, session->uuid, sizeof(session->uuid));
	header->stream_id = ltt_chan->id;
	header->ctx.timestamp_begin = tsc;
	header->ctx.timestamp_end = 0;
	header->ctx.events_discarded = 0;
	header->ctx.content_size = 0xFFFFFFFF; /* for debugging */
	header->ctx.packet_size = 0xFFFFFFFF;
	header->ctx.cpu_id = buf->backend.cpu;
}

/*
 * 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 lib_ring_buffer *buf, u64 tsc,
			      unsigned int subbuf_idx, unsigned long data_size)
{
	struct channel *chan = shmp(buf->backend.chan);
	struct packet_header *header =
		(struct packet_header *)
			lib_ring_buffer_offset_address(&buf->backend,
				subbuf_idx * chan->backend.subbuf_size);
	unsigned long records_lost = 0;

	header->ctx.timestamp_end = tsc;
	header->ctx.content_size = data_size * CHAR_BIT; 	/* in bits */
	header->ctx.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);
	header->ctx.events_discarded = records_lost;
}

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

static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu)
{
}

static const struct 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 = 32,
	.alloc = RING_BUFFER_ALLOC_PER_CPU,
	.sync = RING_BUFFER_SYNC_PER_CPU,
	.mode = RING_BUFFER_MODE_TEMPLATE,
	.backend = RING_BUFFER_PAGE,
	.output = RING_BUFFER_SPLICE,
	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	.ipi = RING_BUFFER_IPI_BARRIER,
	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
};

static
struct 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 *shmid)
{
	return channel_create(&client_config, name, ltt_chan, buf_addr,
			      subbuf_size, num_subbuf, switch_timer_interval,
			      read_timer_interval, shmid);
}

static
void ltt_channel_destroy(struct channel *chan)
{
	channel_destroy(chan);
}

static
struct lib_ring_buffer *ltt_buffer_read_open(struct channel *chan)
{
	struct lib_ring_buffer *buf;
	int cpu;

	for_each_channel_cpu(cpu, chan) {
		buf = channel_get_ring_buffer(&client_config, chan, cpu);
		if (!lib_ring_buffer_open_read(buf))
			return buf;
	}
	return NULL;
}

static
void ltt_buffer_read_close(struct lib_ring_buffer *buf)
{
	lib_ring_buffer_release_read(buf);
}

static
int ltt_event_reserve(struct lib_ring_buffer_ctx *ctx,
		      uint32_t event_id)
{
	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	int ret, cpu;

	cpu = lib_ring_buffer_get_cpu(&client_config);
	if (cpu < 0)
		return -EPERM;
	ctx->cpu = cpu;

	switch (ltt_chan->header_type) {
	case 1:	/* compact */
		if (event_id > 30)
			ctx->rflags |= LTT_RFLAG_EXTENDED;
		break;
	case 2:	/* large */
		if (event_id > 65534)
			ctx->rflags |= LTT_RFLAG_EXTENDED;
		break;
	default:
		WARN_ON_ONCE(1);
	}

	ret = lib_ring_buffer_reserve(&client_config, ctx);
	if (ret)
		goto put;
	ltt_write_event_header(&client_config, ctx, event_id);
	return 0;
put:
	lib_ring_buffer_put_cpu(&client_config);
	return ret;
}

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

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

#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 struct ltt_transport ltt_relay_transport = {
	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	.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 = NULL,	/* Would be racy anyway */
		//.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,
	},
};

static
void __attribute__((constructor)) ltt_ring_buffer_client_init(void)
{
	printf("LTT : ltt ring buffer client init\n");
	ltt_transport_register(&ltt_relay_transport);
}

static
void __attribute__((destructor)) ltt_ring_buffer_client_exit(void)
{
	printf("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	*
	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
9f3fdbc6 MD	11	#include <stdint.h>
	12	#include "ust/bitfield.h"
	13	#include "ust/clock.h"
3d1fc7fd MD	14	#include "ltt-events.h"
3d1fc7fd MD	15	#include "ltt-tracer.h"
9f3fdbc6	16	#include "../libringbuffer/frontend_types.h"
3d1fc7fd MD	17
	18	/*
	19	* Keep the natural field alignment for _each field_ within this structure if
	20	* you ever add/remove a field from this header. Packed attribute is not used
	21	* because gcc generates poor code on at least powerpc and mips. Don't ever
	22	* let gcc add padding between the structure elements.
	23	*/
	24
	25	struct packet_header {
	26	/* Trace packet header */
	27	uint32_t magic; /*
	28	* Trace magic number.
	29	* contains endianness information.
	30	*/
	31	uint8_t uuid[16];
	32	uint32_t stream_id;
	33
	34	struct {
	35	/* Stream packet context */
	36	uint64_t timestamp_begin; /* Cycle count at subbuffer start */
	37	uint64_t timestamp_end; /* Cycle count at subbuffer end */
	38	uint32_t events_discarded; /*
	39	* Events lost in this subbuffer since
	40	* the beginning of the trace.
	41	* (may overflow)
	42	*/
	43	uint32_t content_size; /* Size of data in subbuffer */
	44	uint32_t packet_size; /* Subbuffer size (include padding) */
	45	uint32_t cpu_id; /* CPU id associated with stream */
	46	uint8_t header_end; /* End of header */
	47	} ctx;
	48	};
	49
	50
	51	static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
	52	{
	53	return trace_clock_read64();
	54	}
	55
	56	static inline
	57	size_t ctx_get_size(size_t offset, struct lttng_ctx *ctx)
	58	{
	59	int i;
	60	size_t orig_offset = offset;
	61
	62	if (likely(!ctx))
	63	return 0;
	64	for (i = 0; i < ctx->nr_fields; i++)
	65	offset += ctx->fields[i].get_size(offset);
	66	return offset - orig_offset;
	67	}
	68
	69	static inline
	70	void ctx_record(struct lib_ring_buffer_ctx *bufctx,
	71	struct ltt_channel *chan,
	72	struct lttng_ctx *ctx)
	73	{
	74	int i;
	75
	76	if (likely(!ctx))
	77	return;
	78	for (i = 0; i < ctx->nr_fields; i++)
	79	ctx->fields[i].record(&ctx->fields[i], bufctx, chan);
	80	}
81
82	/*
83	* record_header_size - Calculate the header size and padding necessary.
84	* @config: ring buffer instance configuration
85	* @chan: channel
86	* @offset: offset in the write buffer
87	* @pre_header_padding: padding to add before the header (output)
88	* @ctx: reservation context
89	*
90	* Returns the event header size (including padding).
91	*
92	* The payload must itself determine its own alignment from the biggest type it
93	* contains.
94	*/
95	static __inline__
96	unsigned char record_header_size(const struct lib_ring_buffer_config *config,
97	struct channel *chan, size_t offset,
98	size_t *pre_header_padding,
99	struct lib_ring_buffer_ctx *ctx)
100	{
101	struct ltt_channel *ltt_chan = channel_get_private(chan);
102	struct ltt_event *event = ctx->priv;
103	size_t orig_offset = offset;
104	size_t padding;
105
106	switch (ltt_chan->header_type) {
107	case 1: /* compact */
108	padding = lib_ring_buffer_align(offset, ltt_alignof(uint32_t));
109	offset += padding;
110	if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC \| LTT_RFLAG_EXTENDED))) {
111	offset += sizeof(uint32_t); /* id and timestamp */
112	} else {
113	/* Minimum space taken by 5-bit id */
114	offset += sizeof(uint8_t);
115	/* Align extended struct on largest member */
116	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
117	offset += sizeof(uint32_t); /* id */
118	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
119	offset += sizeof(uint64_t); /* timestamp */
120	}
121	break;
122	case 2: /* large */
123	padding = lib_ring_buffer_align(offset, ltt_alignof(uint16_t));
124	offset += padding;
125	offset += sizeof(uint16_t);
126	if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC \| LTT_RFLAG_EXTENDED))) {
127	offset += lib_ring_buffer_align(offset, ltt_alignof(uint32_t));
128	offset += sizeof(uint32_t); /* timestamp */
129	} else {
130	/* Align extended struct on largest member */
131	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
132	offset += sizeof(uint32_t); /* id */
133	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
134	offset += sizeof(uint64_t); /* timestamp */
135	}
136	break;
137	default:
9f3fdbc6	138	padding = 0;
3d1fc7fd MD	139	WARN_ON_ONCE(1);
	140	}
	141	offset += ctx_get_size(offset, event->ctx);
	142	offset += ctx_get_size(offset, ltt_chan->ctx);
	143
	144	*pre_header_padding = padding;
	145	return offset - orig_offset;
	146	}
	147
9f3fdbc6	148	#include "../libringbuffer/api.h"
3d1fc7fd	149
9f3fdbc6	150	static
3d1fc7fd MD	151	void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
	152	struct lib_ring_buffer_ctx *ctx,
	153	uint32_t event_id);
	154
	155	/*
	156	* ltt_write_event_header
	157	*
	158	* Writes the event header to the offset (already aligned on 32-bits).
	159	*
	160	* @config: ring buffer instance configuration
	161	* @ctx: reservation context
	162	* @event_id: event ID
	163	*/
	164	static __inline__
	165	void ltt_write_event_header(const struct lib_ring_buffer_config *config,
	166	struct lib_ring_buffer_ctx *ctx,
	167	uint32_t event_id)
	168	{
	169	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	170	struct ltt_event *event = ctx->priv;
	171
	172	if (unlikely(ctx->rflags))
	173	goto slow_path;
	174
	175	switch (ltt_chan->header_type) {
	176	case 1: /* compact */
	177	{
	178	uint32_t id_time = 0;
	179
	180	bt_bitfield_write(&id_time, uint32_t, 0, 5, event_id);
	181	bt_bitfield_write(&id_time, uint32_t, 5, 27, ctx->tsc);
	182	lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
	183	break;
	184	}
	185	case 2: /* large */
	186	{
	187	uint32_t timestamp = (uint32_t) ctx->tsc;
	188	uint16_t id = event_id;
	189
	190	lib_ring_buffer_write(config, ctx, &id, sizeof(id));
	191	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
	192	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	193	break;
	194	}
	195	default:
	196	WARN_ON_ONCE(1);
	197	}
	198
	199	ctx_record(ctx, ltt_chan, event->ctx);
	200	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
	201
	202	return;
	203
	204	slow_path:
	205	ltt_write_event_header_slow(config, ctx, event_id);
	206	}
	207
9f3fdbc6	208	static
3d1fc7fd MD	209	void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
	210	struct lib_ring_buffer_ctx *ctx,
	211	uint32_t event_id)
	212	{
	213	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	214	struct ltt_event *event = ctx->priv;
	215
	216	switch (ltt_chan->header_type) {
	217	case 1: /* compact */
	218	if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC \| LTT_RFLAG_EXTENDED))) {
	219	uint32_t id_time = 0;
	220
	221	bt_bitfield_write(&id_time, uint32_t, 0, 5, event_id);
	222	bt_bitfield_write(&id_time, uint32_t, 5, 27, ctx->tsc);
	223	lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
	224	} else {
	225	uint8_t id = 0;
	226	uint64_t timestamp = ctx->tsc;
	227
	228	bt_bitfield_write(&id, uint8_t, 0, 5, 31);
	229	lib_ring_buffer_write(config, ctx, &id, sizeof(id));
	230	/* Align extended struct on largest member */
	231	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	232	lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
	233	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	234	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	235	}
	236	break;
	237	case 2: /* large */
	238	{
	239	if (!(ctx->rflags & (RING_BUFFER_RFLAG_FULL_TSC \| LTT_RFLAG_EXTENDED))) {
	240	uint32_t timestamp = (uint32_t) ctx->tsc;
	241	uint16_t id = event_id;
	242
	243	lib_ring_buffer_write(config, ctx, &id, sizeof(id));
	244	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
	245	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	246	} else {
	247	uint16_t id = 65535;
	248	uint64_t timestamp = ctx->tsc;
	249
	250	lib_ring_buffer_write(config, ctx, &id, sizeof(id));
	251	/* Align extended struct on largest member */
	252	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	253	lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
	254	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	255	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	256	}
	257	break;
	258	}
	259	default:
	260	WARN_ON_ONCE(1);
	261	}
	262	ctx_record(ctx, ltt_chan, event->ctx);
	263	ctx_record(ctx, ltt_chan, ltt_chan->ctx);
	264	}
	265
	266	static const struct lib_ring_buffer_config client_config;
	267
	268	static u64 client_ring_buffer_clock_read(struct channel *chan)
	269	{
	270	return lib_ring_buffer_clock_read(chan);
	271	}
	272
273	static
274	size_t client_record_header_size(const struct lib_ring_buffer_config *config,
275	struct channel *chan, size_t offset,
276	size_t *pre_header_padding,
277	struct lib_ring_buffer_ctx *ctx)
278	{
279	return record_header_size(config, chan, offset,
280	pre_header_padding, ctx);
281	}
282
283	/**
284	* client_packet_header_size - called on buffer-switch to a new sub-buffer
285	*
286	* Return header size without padding after the structure. Don't use packed
287	* structure because gcc generates inefficient code on some architectures
288	* (powerpc, mips..)
289	*/
290	static size_t client_packet_header_size(void)
291	{
292	return offsetof(struct packet_header, ctx.header_end);
293	}
294
295	static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
296	unsigned int subbuf_idx)
297	{
9f3fdbc6	298	struct channel *chan = shmp(buf->backend.chan);
3d1fc7fd MD	299	struct packet_header *header =
	300	(struct packet_header *)
	301	lib_ring_buffer_offset_address(&buf->backend,
	302	subbuf_idx * chan->backend.subbuf_size);
	303	struct ltt_channel *ltt_chan = channel_get_private(chan);
	304	struct ltt_session *session = ltt_chan->session;
	305
	306	header->magic = CTF_MAGIC_NUMBER;
9f3fdbc6	307	memcpy(header->uuid, session->uuid, sizeof(session->uuid));
3d1fc7fd MD	308	header->stream_id = ltt_chan->id;
	309	header->ctx.timestamp_begin = tsc;
	310	header->ctx.timestamp_end = 0;
	311	header->ctx.events_discarded = 0;
	312	header->ctx.content_size = 0xFFFFFFFF; /* for debugging */
	313	header->ctx.packet_size = 0xFFFFFFFF;
	314	header->ctx.cpu_id = buf->backend.cpu;
	315	}
	316
	317	/*
	318	* offset is assumed to never be 0 here : never deliver a completely empty
	319	* subbuffer. data_size is between 1 and subbuf_size.
	320	*/
	321	static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
	322	unsigned int subbuf_idx, unsigned long data_size)
	323	{
9f3fdbc6	324	struct channel *chan = shmp(buf->backend.chan);
3d1fc7fd MD	325	struct packet_header *header =
	326	(struct packet_header *)
	327	lib_ring_buffer_offset_address(&buf->backend,
	328	subbuf_idx * chan->backend.subbuf_size);
	329	unsigned long records_lost = 0;
	330
	331	header->ctx.timestamp_end = tsc;
	332	header->ctx.content_size = data_size * CHAR_BIT; /* in bits */
	333	header->ctx.packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
	334	records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf);
	335	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	336	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	337	header->ctx.events_discarded = records_lost;
	338	}
	339
	340	static int client_buffer_create(struct lib_ring_buffer buf, void priv,
	341	int cpu, const char *name)
	342	{
	343	return 0;
	344	}
	345
	346	static void client_buffer_finalize(struct lib_ring_buffer buf, void priv, int cpu)
	347	{
	348	}
	349
	350	static const struct lib_ring_buffer_config client_config = {
	351	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	352	.cb.record_header_size = client_record_header_size,
	353	.cb.subbuffer_header_size = client_packet_header_size,
	354	.cb.buffer_begin = client_buffer_begin,
	355	.cb.buffer_end = client_buffer_end,
	356	.cb.buffer_create = client_buffer_create,
	357	.cb.buffer_finalize = client_buffer_finalize,
	358
	359	.tsc_bits = 32,
	360	.alloc = RING_BUFFER_ALLOC_PER_CPU,
	361	.sync = RING_BUFFER_SYNC_PER_CPU,
	362	.mode = RING_BUFFER_MODE_TEMPLATE,
	363	.backend = RING_BUFFER_PAGE,
	364	.output = RING_BUFFER_SPLICE,
	365	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	366	.ipi = RING_BUFFER_IPI_BARRIER,
	367	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
	368	};
	369
	370	static
	371	struct channel _channel_create(const char name,
	372	struct ltt_channel ltt_chan, void buf_addr,
	373	size_t subbuf_size, size_t num_subbuf,
	374	unsigned int switch_timer_interval,
9f3fdbc6 MD	375	unsigned int read_timer_interval,
9f3fdbc6 MD	376	int *shmid)
3d1fc7fd MD	377	{
	378	return channel_create(&client_config, name, ltt_chan, buf_addr,
	379	subbuf_size, num_subbuf, switch_timer_interval,
9f3fdbc6	380	read_timer_interval, shmid);
3d1fc7fd MD	381	}
	382
	383	static
	384	void ltt_channel_destroy(struct channel *chan)
	385	{
	386	channel_destroy(chan);
	387	}
	388
	389	static
	390	struct lib_ring_buffer ltt_buffer_read_open(struct channel chan)
	391	{
	392	struct lib_ring_buffer *buf;
	393	int cpu;
	394
	395	for_each_channel_cpu(cpu, chan) {
	396	buf = channel_get_ring_buffer(&client_config, chan, cpu);
	397	if (!lib_ring_buffer_open_read(buf))
	398	return buf;
	399	}
	400	return NULL;
	401	}
	402
	403	static
	404	void ltt_buffer_read_close(struct lib_ring_buffer *buf)
	405	{
	406	lib_ring_buffer_release_read(buf);
	407	}
	408
	409	static
	410	int ltt_event_reserve(struct lib_ring_buffer_ctx *ctx,
	411	uint32_t event_id)
	412	{
	413	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	414	int ret, cpu;
	415
	416	cpu = lib_ring_buffer_get_cpu(&client_config);
	417	if (cpu < 0)
	418	return -EPERM;
	419	ctx->cpu = cpu;
	420
	421	switch (ltt_chan->header_type) {
	422	case 1: /* compact */
	423	if (event_id > 30)
	424	ctx->rflags \|= LTT_RFLAG_EXTENDED;
	425	break;
	426	case 2: /* large */
	427	if (event_id > 65534)
	428	ctx->rflags \|= LTT_RFLAG_EXTENDED;
	429	break;
	430	default:
	431	WARN_ON_ONCE(1);
	432	}
	433
	434	ret = lib_ring_buffer_reserve(&client_config, ctx);
	435	if (ret)
	436	goto put;
	437	ltt_write_event_header(&client_config, ctx, event_id);
	438	return 0;
	439	put:
	440	lib_ring_buffer_put_cpu(&client_config);
	441	return ret;
	442	}
	443
	444	static
445	void ltt_event_commit(struct lib_ring_buffer_ctx *ctx)
446	{
447	lib_ring_buffer_commit(&client_config, ctx);
448	lib_ring_buffer_put_cpu(&client_config);
449	}
450
451	static
452	void ltt_event_write(struct lib_ring_buffer_ctx ctx, const void src,
453	size_t len)
454	{
455	lib_ring_buffer_write(&client_config, ctx, src, len);
456	}
457
9f3fdbc6	458	#if 0
3d1fc7fd MD	459	static
	460	wait_queue_head_t ltt_get_reader_wait_queue(struct channel chan)
	461	{
	462	return &chan->read_wait;
	463	}
	464
	465	static
	466	wait_queue_head_t ltt_get_hp_wait_queue(struct channel chan)
	467	{
	468	return &chan->hp_wait;
	469	}
9f3fdbc6	470	#endif //0
3d1fc7fd MD	471
	472	static
	473	int ltt_is_finalized(struct channel *chan)
	474	{
	475	return lib_ring_buffer_channel_is_finalized(chan);
	476	}
	477
	478	static
	479	int ltt_is_disabled(struct channel *chan)
	480	{
	481	return lib_ring_buffer_channel_is_disabled(chan);
	482	}
	483
	484	static struct ltt_transport ltt_relay_transport = {
	485	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
3d1fc7fd MD	486	.ops = {
	487	.channel_create = _channel_create,
	488	.channel_destroy = ltt_channel_destroy,
	489	.buffer_read_open = ltt_buffer_read_open,
	490	.buffer_read_close = ltt_buffer_read_close,
	491	.event_reserve = ltt_event_reserve,
	492	.event_commit = ltt_event_commit,
	493	.event_write = ltt_event_write,
	494	.packet_avail_size = NULL, /* Would be racy anyway */
9f3fdbc6 MD	495	//.get_reader_wait_queue = ltt_get_reader_wait_queue,
9f3fdbc6 MD	496	//.get_hp_wait_queue = ltt_get_hp_wait_queue,
3d1fc7fd MD	497	.is_finalized = ltt_is_finalized,
	498	.is_disabled = ltt_is_disabled,
	499	},
	500	};
	501
9f3fdbc6 MD	502	static
9f3fdbc6 MD	503	void __attribute__((constructor)) ltt_ring_buffer_client_init(void)
3d1fc7fd	504	{
9f3fdbc6	505	printf("LTT : ltt ring buffer client init\n");
3d1fc7fd	506	ltt_transport_register(&ltt_relay_transport);
3d1fc7fd MD	507	}
3d1fc7fd MD	508
9f3fdbc6 MD	509	static
9f3fdbc6 MD	510	void __attribute__((destructor)) ltt_ring_buffer_client_exit(void)
3d1fc7fd	511	{
9f3fdbc6	512	printf("LTT : ltt ring buffer client exit\n");
3d1fc7fd MD	513	ltt_transport_unregister(&ltt_relay_transport);
3d1fc7fd MD	514	}