[lttng-modules.git] / 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 <linux/module.h>
#include <linux/types.h>
#include "lib/bitfield.h"
#include "wrapper/vmalloc.h"	/* for wrapper_vmalloc_sync_all() */
#include "wrapper/trace-clock.h"
#include "ltt-events.h"
#include "ltt-tracer.h"
#include "wrapper/ringbuffer/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();
}

/*
 * record_header_size - Calculate the header size and padding necessary.
 * @config: ring buffer instance configuration
 * @chan: channel
 * @offset: offset in the write buffer
 * @data_size: size of the payload
 * @pre_header_padding: padding to add before the header (output)
 * @rflags: reservation flags
 * @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 data_size, size_t *pre_header_padding,
				 unsigned int rflags,
				 struct lib_ring_buffer_ctx *ctx)
{
	struct ltt_channel *ltt_chan = channel_get_private(chan);
	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 (!(rflags & RING_BUFFER_RFLAG_FULL_TSC)) {
			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 (!(rflags & RING_BUFFER_RFLAG_FULL_TSC)) {
			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:
		WARN_ON(1);
	}

	*pre_header_padding = padding;
	return offset - orig_offset;
}

#include "wrapper/ringbuffer/api.h"

extern
void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
				 struct lib_ring_buffer_ctx *ctx,
				 u16 eID, u32 event_size);

/*
 * ltt_write_event_header
 *
 * Writes the event header to the offset (already aligned on 32-bits).
 *
 * @config: ring buffer instance configuration
 * @ctx: reservation context
 * @eID : event ID
 * @event_size : size of the event, excluding the event header.
 */
static __inline__
void ltt_write_event_header(const struct lib_ring_buffer_config *config,
			    struct lib_ring_buffer_ctx *ctx,
			    u16 eID, u32 event_size)
{
	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);

	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, eID);
		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 */
	{
		uint16_t event_id = eID;
		uint32_t timestamp = (uint32_t) ctx->tsc;

		lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
		lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
		lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
		break;
	}
	default:
		WARN_ON(1);
	}
	return;

slow_path:
	ltt_write_event_header_slow(config, ctx, eID, event_size);
}

/*
 * TODO: For now, we only support 65536 event ids per channel.
 */
void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
				   struct lib_ring_buffer_ctx *ctx,
				   u16 eID, u32 event_size)
{
	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);

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

			bt_bitfield_write(&id_time, uint32_t, 0, 5, eID);
			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;
			uint32_t event_id = (uint32_t) eID;
			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)) {
			uint16_t event_id = eID;
			uint32_t timestamp = (uint32_t) ctx->tsc;

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

			lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_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_ext, sizeof(event_id_ext));
			lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
			lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
		}
		break;
	}
	default:
		WARN_ON(1);
	}
}

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 data_size,
				 size_t *pre_header_padding,
				 unsigned int rflags,
				 struct lib_ring_buffer_ctx *ctx)
{
	return record_header_size(config, chan, offset, data_size,
				  pre_header_padding, rflags, 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 = 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.b, 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 = 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)
{
	return channel_create(&client_config, name, ltt_chan, buf_addr,
			      subbuf_size, num_subbuf, switch_timer_interval,
			      read_timer_interval);
}

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)
{
	int ret, cpu;

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

	ret = lib_ring_buffer_reserve(&client_config, ctx);
	if (ret)
		goto put;
	return ret;

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);
}

static
wait_queue_head_t *ltt_get_reader_wait_queue(struct ltt_channel *chan)
{
	return &chan->chan->read_wait;
}

static struct ltt_transport ltt_relay_transport = {
	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	.owner = THIS_MODULE,
	.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,
	},
};

static int __init ltt_ring_buffer_client_init(void)
{
	/*
	 * This vmalloc sync all also takes care of the lib ring buffer
	 * vmalloc'd module pages when it is built as a module into LTTng.
	 */
	wrapper_vmalloc_sync_all();
	printk(KERN_INFO "LTT : ltt ring buffer client init\n");
	ltt_transport_register(&ltt_relay_transport);
	return 0;
}

module_init(ltt_ring_buffer_client_init);

static void __exit ltt_ring_buffer_client_exit(void)
{
	printk(KERN_INFO "LTT : ltt ring buffer client exit\n");
	ltt_transport_unregister(&ltt_relay_transport);
}

module_exit(ltt_ring_buffer_client_exit);

MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Mathieu Desnoyers");
MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
		   " client");
Commit	Line	Data
7514523f	1	/*
3d084699	2	* ltt-ring-buffer-client.h
7514523f MD	3	*
	4	* Copyright (C) 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	5	*
3d084699	6	* LTTng lib ring buffer client template.
7514523f MD	7	*
	8	* Dual LGPL v2.1/GPL v2 license.
	9	*/
	10
	11	#include <linux/module.h>
c0e31d2e	12	#include <linux/types.h>
9115fbdc	13	#include "lib/bitfield.h"
b13f3ebe	14	#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
f3bc08c5	15	#include "wrapper/trace-clock.h"
c0e31d2e	16	#include "ltt-events.h"
7514523f	17	#include "ltt-tracer.h"
9115fbdc	18	#include "wrapper/ringbuffer/frontend_types.h"
7514523f	19
d793d5e1 MD	20	/*
	21	* Keep the natural field alignment for _each field_ within this structure if
	22	* you ever add/remove a field from this header. Packed attribute is not used
	23	* because gcc generates poor code on at least powerpc and mips. Don't ever
	24	* let gcc add padding between the structure elements.
	25	*/
9115fbdc	26
d793d5e1	27	struct packet_header {
9115fbdc	28	/* Trace packet header */
d793d5e1 MD	29	uint32_t magic; /*
	30	* Trace magic number.
	31	* contains endianness information.
	32	*/
1ec3f75a	33	uint8_t uuid[16];
d793d5e1	34	uint32_t stream_id;
9115fbdc MD	35
	36	struct {
	37	/* Stream packet context */
	38	uint64_t timestamp_begin; /* Cycle count at subbuffer start */
	39	uint64_t timestamp_end; /* Cycle count at subbuffer end */
	40	uint32_t events_discarded; /*
	41	* Events lost in this subbuffer since
	42	* the beginning of the trace.
	43	* (may overflow)
	44	*/
	45	uint32_t content_size; /* Size of data in subbuffer */
	46	uint32_t packet_size; /* Subbuffer size (include padding) */
	47	uint32_t cpu_id; /* CPU id associated with stream */
	48	uint8_t header_end; /* End of header */
	49	} ctx;
d793d5e1 MD	50	};
	51
	52
881833e3 MD	53	static inline notrace u64 lib_ring_buffer_clock_read(struct channel *chan)
	54	{
	55	return trace_clock_read64();
	56	}
	57
	58	/*
	59	* record_header_size - Calculate the header size and padding necessary.
	60	* @config: ring buffer instance configuration
	61	* @chan: channel
	62	* @offset: offset in the write buffer
	63	* @data_size: size of the payload
	64	* @pre_header_padding: padding to add before the header (output)
	65	* @rflags: reservation flags
	66	* @ctx: reservation context
	67	*
	68	* Returns the event header size (including padding).
	69	*
881833e3 MD	70	* The payload must itself determine its own alignment from the biggest type it
	71	* contains.
	72	*/
	73	static __inline__
	74	unsigned char record_header_size(const struct lib_ring_buffer_config *config,
	75	struct channel *chan, size_t offset,
	76	size_t data_size, size_t *pre_header_padding,
	77	unsigned int rflags,
	78	struct lib_ring_buffer_ctx *ctx)
	79	{
9115fbdc	80	struct ltt_channel *ltt_chan = channel_get_private(chan);
881833e3 MD	81	size_t orig_offset = offset;
	82	size_t padding;
	83
9115fbdc MD	84	switch (ltt_chan->header_type) {
	85	case 1: /* compact */
	86	padding = lib_ring_buffer_align(offset, ltt_alignof(uint32_t));
	87	offset += padding;
	88	if (!(rflags & RING_BUFFER_RFLAG_FULL_TSC)) {
	89	offset += sizeof(uint32_t); /* id and timestamp */
	90	} else {
	91	/* Minimum space taken by 5-bit id */
	92	offset += sizeof(uint8_t);
	93	/* Align extended struct on largest member */
	94	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
	95	offset += sizeof(uint32_t); /* id */
	96	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
	97	offset += sizeof(uint64_t); /* timestamp */
	98	}
	99	break;
	100	case 2: /* large */
	101	padding = lib_ring_buffer_align(offset, ltt_alignof(uint16_t));
	102	offset += padding;
	103	offset += sizeof(uint16_t);
	104	if (!(rflags & RING_BUFFER_RFLAG_FULL_TSC)) {
	105	offset += lib_ring_buffer_align(offset, ltt_alignof(uint32_t));
	106	offset += sizeof(uint32_t); /* timestamp */
	107	} else {
	108	/* Align extended struct on largest member */
	109	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
	110	offset += sizeof(uint32_t); /* id */
	111	offset += lib_ring_buffer_align(offset, ltt_alignof(uint64_t));
	112	offset += sizeof(uint64_t); /* timestamp */
	113
881833e3	114	}
9115fbdc MD	115	break;
	116	default:
	117	WARN_ON(1);
881833e3 MD	118	}
	119
	120	*pre_header_padding = padding;
	121	return offset - orig_offset;
	122	}
	123
	124	#include "wrapper/ringbuffer/api.h"
	125
	126	extern
	127	void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
	128	struct lib_ring_buffer_ctx *ctx,
	129	u16 eID, u32 event_size);
	130
	131	/*
	132	* ltt_write_event_header
	133	*
	134	* Writes the event header to the offset (already aligned on 32-bits).
	135	*
	136	* @config: ring buffer instance configuration
	137	* @ctx: reservation context
	138	* @eID : event ID
	139	* @event_size : size of the event, excluding the event header.
	140	*/
	141	static __inline__
	142	void ltt_write_event_header(const struct lib_ring_buffer_config *config,
	143	struct lib_ring_buffer_ctx *ctx,
	144	u16 eID, u32 event_size)
	145	{
9115fbdc	146	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
881833e3 MD	147
	148	if (unlikely(ctx->rflags))
	149	goto slow_path;
	150
9115fbdc MD	151	switch (ltt_chan->header_type) {
	152	case 1: /* compact */
	153	{
	154	uint32_t id_time = 0;
	155
	156	bt_bitfield_write(&id_time, uint32_t, 0, 5, eID);
	157	bt_bitfield_write(&id_time, uint32_t, 5, 27, ctx->tsc);
	158	lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
	159	break;
	160	}
	161	case 2: /* large */
	162	{
	163	uint16_t event_id = eID;
	164	uint32_t timestamp = (uint32_t) ctx->tsc;
	165
	166	lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
	167	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
	168	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	169	break;
	170	}
	171	default:
	172	WARN_ON(1);
	173	}
	174	return;
881833e3 MD	175
	176	slow_path:
	177	ltt_write_event_header_slow(config, ctx, eID, event_size);
	178	}
	179
9115fbdc MD	180	/*
	181	* TODO: For now, we only support 65536 event ids per channel.
	182	*/
881833e3 MD	183	void ltt_write_event_header_slow(const struct lib_ring_buffer_config *config,
	184	struct lib_ring_buffer_ctx *ctx,
	185	u16 eID, u32 event_size)
	186	{
9115fbdc MD	187	struct ltt_channel *ltt_chan = channel_get_private(ctx->chan);
	188
	189	switch (ltt_chan->header_type) {
	190	case 1: /* compact */
	191	if (!(ctx->rflags & RING_BUFFER_RFLAG_FULL_TSC)) {
	192	uint32_t id_time = 0;
	193
	194	bt_bitfield_write(&id_time, uint32_t, 0, 5, eID);
	195	bt_bitfield_write(&id_time, uint32_t, 5, 27, ctx->tsc);
	196	lib_ring_buffer_write(config, ctx, &id_time, sizeof(id_time));
	197	} else {
	198	uint8_t id = 0;
	199	uint32_t event_id = (uint32_t) eID;
	200	uint64_t timestamp = ctx->tsc;
	201
	202	bt_bitfield_write(&id, uint8_t, 0, 5, 31);
	203	lib_ring_buffer_write(config, ctx, &id, sizeof(id));
	204	/* Align extended struct on largest member */
	205	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	206	lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
	207	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	208	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	209	}
881833e3	210	break;
9115fbdc MD	211	case 2: /* large */
	212	{
	213	if (!(ctx->rflags & RING_BUFFER_RFLAG_FULL_TSC)) {
	214	uint16_t event_id = eID;
	215	uint32_t timestamp = (uint32_t) ctx->tsc;
	216
	217	lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
	218	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint32_t));
	219	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	220	} else {
	221	uint16_t event_id = 65535;
	222	uint32_t event_id_ext = (uint32_t) eID;
	223	uint64_t timestamp = ctx->tsc;
	224
	225	lib_ring_buffer_write(config, ctx, &event_id, sizeof(event_id));
	226	/* Align extended struct on largest member */
	227	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	228	lib_ring_buffer_write(config, ctx, &event_id_ext, sizeof(event_id_ext));
	229	lib_ring_buffer_align_ctx(ctx, ltt_alignof(uint64_t));
	230	lib_ring_buffer_write(config, ctx, &timestamp, sizeof(timestamp));
	231	}
881833e3	232	break;
881833e3	233	}
9115fbdc MD	234	default:
9115fbdc MD	235	WARN_ON(1);
881833e3 MD	236	}
	237	}
	238
7514523f MD	239	static const struct lib_ring_buffer_config client_config;
	240
	241	static u64 client_ring_buffer_clock_read(struct channel *chan)
	242	{
	243	return lib_ring_buffer_clock_read(chan);
	244	}
	245
1e2015dc	246	static
7514523f MD	247	size_t client_record_header_size(const struct lib_ring_buffer_config *config,
	248	struct channel *chan, size_t offset,
	249	size_t data_size,
	250	size_t *pre_header_padding,
	251	unsigned int rflags,
	252	struct lib_ring_buffer_ctx *ctx)
	253	{
	254	return record_header_size(config, chan, offset, data_size,
	255	pre_header_padding, rflags, ctx);
	256	}
	257
	258	/**
1c25284c	259	* client_packet_header_size - called on buffer-switch to a new sub-buffer
7514523f MD	260	*
	261	* Return header size without padding after the structure. Don't use packed
	262	* structure because gcc generates inefficient code on some architectures
	263	* (powerpc, mips..)
	264	*/
1c25284c	265	static size_t client_packet_header_size(void)
7514523f	266	{
9115fbdc	267	return offsetof(struct packet_header, ctx.header_end);
7514523f MD	268	}
	269
	270	static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
	271	unsigned int subbuf_idx)
	272	{
	273	struct channel *chan = buf->backend.chan;
1c25284c MD	274	struct packet_header *header =
1c25284c MD	275	(struct packet_header *)
7514523f MD	276	lib_ring_buffer_offset_address(&buf->backend,
7514523f MD	277	subbuf_idx * chan->backend.subbuf_size);
9115fbdc MD	278	struct ltt_channel *ltt_chan = channel_get_private(chan);
9115fbdc MD	279	struct ltt_session *session = ltt_chan->session;
7514523f	280
d793d5e1	281	header->magic = CTF_MAGIC_NUMBER;
1ec3f75a	282	memcpy(header->uuid, session->uuid.b, sizeof(session->uuid));
9115fbdc MD	283	header->stream_id = ltt_chan->id;
	284	header->ctx.timestamp_begin = tsc;
	285	header->ctx.timestamp_end = 0;
	286	header->ctx.events_discarded = 0;
	287	header->ctx.content_size = 0xFFFFFFFF; /* for debugging */
	288	header->ctx.packet_size = 0xFFFFFFFF;
	289	header->ctx.cpu_id = buf->backend.cpu;
7514523f MD	290	}
	291
	292	/*
	293	* offset is assumed to never be 0 here : never deliver a completely empty
	294	* subbuffer. data_size is between 1 and subbuf_size.
	295	*/
	296	static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
	297	unsigned int subbuf_idx, unsigned long data_size)
	298	{
	299	struct channel *chan = buf->backend.chan;
1c25284c MD	300	struct packet_header *header =
1c25284c MD	301	(struct packet_header *)
7514523f MD	302	lib_ring_buffer_offset_address(&buf->backend,
	303	subbuf_idx * chan->backend.subbuf_size);
	304	unsigned long records_lost = 0;
	305
9115fbdc	306	header->ctx.timestamp_end = tsc;
05d32c64 MD	307	header->ctx.content_size = data_size * CHAR_BIT; /* in bits */
05d32c64 MD	308	header->ctx.packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
7514523f MD	309	records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf);
	310	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	311	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
9115fbdc	312	header->ctx.events_discarded = records_lost;
7514523f MD	313	}
	314
	315	static int client_buffer_create(struct lib_ring_buffer buf, void priv,
	316	int cpu, const char *name)
	317	{
1c25284c	318	return 0;
7514523f MD	319	}
	320
	321	static void client_buffer_finalize(struct lib_ring_buffer buf, void priv, int cpu)
	322	{
7514523f MD	323	}
	324
	325	static const struct lib_ring_buffer_config client_config = {
	326	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	327	.cb.record_header_size = client_record_header_size,
1c25284c	328	.cb.subbuffer_header_size = client_packet_header_size,
7514523f MD	329	.cb.buffer_begin = client_buffer_begin,
	330	.cb.buffer_end = client_buffer_end,
	331	.cb.buffer_create = client_buffer_create,
	332	.cb.buffer_finalize = client_buffer_finalize,
	333
	334	.tsc_bits = 32,
	335	.alloc = RING_BUFFER_ALLOC_PER_CPU,
	336	.sync = RING_BUFFER_SYNC_PER_CPU,
3d084699	337	.mode = RING_BUFFER_MODE_TEMPLATE,
7514523f MD	338	.backend = RING_BUFFER_PAGE,
	339	.output = RING_BUFFER_SPLICE,
	340	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	341	.ipi = RING_BUFFER_IPI_BARRIER,
	342	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
	343	};
	344
1e2015dc	345	static
1c25284c	346	struct channel _channel_create(const char name,
9115fbdc	347	struct ltt_channel ltt_chan, void buf_addr,
1c25284c MD	348	size_t subbuf_size, size_t num_subbuf,
	349	unsigned int switch_timer_interval,
	350	unsigned int read_timer_interval)
7514523f	351	{
9115fbdc	352	return channel_create(&client_config, name, ltt_chan, buf_addr,
7514523f MD	353	subbuf_size, num_subbuf, switch_timer_interval,
7514523f MD	354	read_timer_interval);
7514523f MD	355	}
7514523f MD	356
1e2015dc	357	static
7514523f MD	358	void ltt_channel_destroy(struct channel *chan)
7514523f MD	359	{
7514523f	360	channel_destroy(chan);
7514523f MD	361	}
7514523f MD	362
ad1c05e1 MD	363	static
	364	struct lib_ring_buffer ltt_buffer_read_open(struct channel chan)
	365	{
	366	struct lib_ring_buffer *buf;
	367	int cpu;
	368
1c25284c MD	369	for_each_channel_cpu(cpu, chan) {
1c25284c MD	370	buf = channel_get_ring_buffer(&client_config, chan, cpu);
ad1c05e1 MD	371	if (!lib_ring_buffer_open_read(buf))
	372	return buf;
	373	}
	374	return NULL;
	375	}
	376
	377	static
1c25284c	378	void ltt_buffer_read_close(struct lib_ring_buffer *buf)
ad1c05e1 MD	379	{
ad1c05e1 MD	380	lib_ring_buffer_release_read(buf);
1c25284c MD	381
	382	}
	383
c099397a	384	static
1c25284c MD	385	int ltt_event_reserve(struct lib_ring_buffer_ctx *ctx)
	386	{
	387	int ret, cpu;
	388
	389	cpu = lib_ring_buffer_get_cpu(&client_config);
	390	if (cpu < 0)
	391	return -EPERM;
	392	ctx->cpu = cpu;
	393
	394	ret = lib_ring_buffer_reserve(&client_config, ctx);
	395	if (ret)
	396	goto put;
	397	return ret;
	398
	399	put:
	400	lib_ring_buffer_put_cpu(&client_config);
	401	return ret;
ad1c05e1 MD	402	}
ad1c05e1 MD	403
c099397a	404	static
1c25284c MD	405	void ltt_event_commit(struct lib_ring_buffer_ctx *ctx)
	406	{
	407	lib_ring_buffer_commit(&client_config, ctx);
	408	lib_ring_buffer_put_cpu(&client_config);
	409	}
	410
c099397a	411	static
e763dbf5 MD	412	void ltt_event_write(struct lib_ring_buffer_ctx ctx, const void src,
	413	size_t len)
	414	{
	415	lib_ring_buffer_write(&client_config, ctx, src, len);
	416	}
1c25284c	417
c099397a MD	418	static
	419	wait_queue_head_t ltt_get_reader_wait_queue(struct ltt_channel chan)
	420	{
	421	return &chan->chan->read_wait;
	422	}
	423
7514523f	424	static struct ltt_transport ltt_relay_transport = {
3d084699	425	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
7514523f MD	426	.owner = THIS_MODULE,
7514523f MD	427	.ops = {
1c25284c MD	428	.channel_create = _channel_create,
1c25284c MD	429	.channel_destroy = ltt_channel_destroy,
ad1c05e1 MD	430	.buffer_read_open = ltt_buffer_read_open,
ad1c05e1 MD	431	.buffer_read_close = ltt_buffer_read_close,
1c25284c MD	432	.event_reserve = ltt_event_reserve,
1c25284c MD	433	.event_commit = ltt_event_commit,
e763dbf5	434	.event_write = ltt_event_write,
1ec3f75a	435	.packet_avail_size = NULL, /* Would be racy anyway */
c099397a	436	.get_reader_wait_queue = ltt_get_reader_wait_queue,
7514523f MD	437	},
	438	};
	439
3d084699	440	static int __init ltt_ring_buffer_client_init(void)
7514523f	441	{
a509e133 MD	442	/*
	443	* This vmalloc sync all also takes care of the lib ring buffer
	444	* vmalloc'd module pages when it is built as a module into LTTng.
	445	*/
6d2a620c	446	wrapper_vmalloc_sync_all();
7514523f MD	447	printk(KERN_INFO "LTT : ltt ring buffer client init\n");
	448	ltt_transport_register(&ltt_relay_transport);
	449	return 0;
	450	}
	451
1c25284c MD	452	module_init(ltt_ring_buffer_client_init);
1c25284c MD	453
3d084699	454	static void __exit ltt_ring_buffer_client_exit(void)
7514523f MD	455	{
	456	printk(KERN_INFO "LTT : ltt ring buffer client exit\n");
	457	ltt_transport_unregister(&ltt_relay_transport);
	458	}
	459
1c25284c MD	460	module_exit(ltt_ring_buffer_client_exit);
1c25284c MD	461
7514523f MD	462	MODULE_LICENSE("GPL and additional rights");
7514523f MD	463	MODULE_AUTHOR("Mathieu Desnoyers");
3d084699 MD	464	MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
3d084699 MD	465	" client");