[lttng-modules.git] / src / lttng-ring-buffer-metadata-client.h

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * lttng-ring-buffer-client.h
 *
 * LTTng lib ring buffer client template.
 *
 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <linux/module.h>
#include <linux/types.h>
#include <wrapper/vmalloc.h>	/* for wrapper_vmalloc_sync_mappings() */
#include <lttng/events.h>
#include <lttng/events-internal.h>
#include <lttng/tracer.h>

static struct lttng_transport lttng_relay_transport;

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_kernel_ring_buffer_config client_config;

static inline
u64 lib_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
{
	return 0;
}

static inline
size_t record_header_size(const struct lttng_kernel_ring_buffer_config *config,
				 struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lttng_kernel_ring_buffer_ctx *ctx,
				 void *client_ctx)
{
	return 0;
}

#include <ringbuffer/api.h>

static u64 client_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
{
	return 0;
}

static
size_t client_record_header_size(const struct lttng_kernel_ring_buffer_config *config,
				 struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lttng_kernel_ring_buffer_ctx *ctx,
				 void *client_ctx)
{
	return 0;
}

/**
 * client_packet_header_size - called on buffer-switch to a new sub-buffer
 *
 * Return header size without padding after the structure. Don't use packed
 * structure because gcc generates inefficient code on some architectures
 * (powerpc, mips..)
 */
static size_t client_packet_header_size(void)
{
	return offsetof(struct metadata_packet_header, header_end);
}

static void client_buffer_begin(struct lttng_kernel_ring_buffer *buf, u64 tsc,
				unsigned int subbuf_idx)
{
	struct lttng_kernel_ring_buffer_channel *chan = 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);
	struct lttng_metadata_cache *metadata_cache =
		channel_get_private(chan);

	header->magic = TSDL_MAGIC_NUMBER;
	memcpy(header->uuid, metadata_cache->uuid.b,
		sizeof(metadata_cache->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_kernel_ring_buffer *buf, u64 tsc,
			      unsigned int subbuf_idx, unsigned long data_size,
			      const struct lttng_kernel_ring_buffer_ctx *ctx)
{
	struct lttng_kernel_ring_buffer_channel *chan = 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);
	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, ctx);
	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, ctx);
	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, ctx);
	WARN_ON_ONCE(records_lost != 0);
}

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

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

static int client_timestamp_begin(const struct lttng_kernel_ring_buffer_config *config,
		struct lttng_kernel_ring_buffer *buf, uint64_t *timestamp_begin)
{
	return -ENOSYS;
}

static int client_timestamp_end(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *timestamp_end)
{
	return -ENOSYS;
}

static int client_events_discarded(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *events_discarded)
{
	return -ENOSYS;
}

static int client_current_timestamp(const struct lttng_kernel_ring_buffer_config *config,
		struct lttng_kernel_ring_buffer *bufb,
		uint64_t *ts)
{
	return -ENOSYS;
}

static int client_content_size(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *content_size)
{
	return -ENOSYS;
}

static int client_packet_size(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *packet_size)
{
	return -ENOSYS;
}

static int client_stream_id(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *stream_id)
{
	return -ENOSYS;
}

static int client_sequence_number(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *seq)
{
	return -ENOSYS;
}

static
int client_instance_id(const struct lttng_kernel_ring_buffer_config *config,
		struct lttng_kernel_ring_buffer *bufb,
		uint64_t *id)
{
	return -ENOSYS;
}

static const struct lttng_kernel_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_OUTPUT_TEMPLATE,
	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	.ipi = RING_BUFFER_IPI_BARRIER,
	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
};

static
void release_priv_ops(void *priv_ops)
{
	module_put(THIS_MODULE);
}

static
void lttng_channel_destroy(struct lttng_kernel_ring_buffer_channel *chan)
{
	channel_destroy(chan);
}

static
struct lttng_kernel_ring_buffer_channel *_channel_create(const char *name,
				void *priv, void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval)
{
	struct lttng_kernel_channel_buffer *lttng_chan = priv;
	struct lttng_kernel_ring_buffer_channel *chan;

	chan = channel_create(&client_config, name,
			      lttng_chan->parent.session->priv->metadata_cache, buf_addr,
			      subbuf_size, num_subbuf, switch_timer_interval,
			      read_timer_interval);
	if (chan) {
		/*
		 * Ensure this module is not unloaded before we finish
		 * using lttng_relay_transport.ops.
		 */
		if (!try_module_get(THIS_MODULE)) {
			printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
			goto error;
		}
		chan->backend.priv_ops = &lttng_relay_transport.ops;
		chan->backend.release_priv_ops = release_priv_ops;
	}
	return chan;

error:
	lttng_channel_destroy(chan);
	return NULL;
}

static
struct lttng_kernel_ring_buffer *lttng_buffer_read_open(struct lttng_kernel_ring_buffer_channel *chan)
{
	struct lttng_kernel_ring_buffer *buf;

	buf = channel_get_ring_buffer(&client_config, chan, 0);
	if (!lib_ring_buffer_open_read(buf))
		return buf;
	return NULL;
}

static
int lttng_buffer_has_read_closed_stream(struct lttng_kernel_ring_buffer_channel *chan)
{
	struct lttng_kernel_ring_buffer *buf;
	int cpu;

	for_each_channel_cpu(cpu, chan) {
		buf = channel_get_ring_buffer(&client_config, chan, cpu);
		if (!atomic_long_read(&buf->active_readers))
			return 1;
	}
	return 0;
}

static
void lttng_buffer_read_close(struct lttng_kernel_ring_buffer *buf)
{
	lib_ring_buffer_release_read(buf);
}

static
int lttng_event_reserve(struct lttng_kernel_ring_buffer_ctx *ctx)
{
	struct lttng_kernel_ring_buffer_channel *chan = ctx->client_priv;
	int ret;

	memset(&ctx->priv, 0, sizeof(ctx->priv));
	ctx->priv.chan = chan;

	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
	if (ret)
		return ret;
	lib_ring_buffer_backend_get_pages(&client_config, ctx,
			&ctx->priv.backend_pages);
	return 0;

}

static
void lttng_event_commit(struct lttng_kernel_ring_buffer_ctx *ctx)
{
	lib_ring_buffer_commit(&client_config, ctx);
}

static
void lttng_event_write(struct lttng_kernel_ring_buffer_ctx *ctx, const void *src,
		     size_t len, size_t alignment)
{
	lib_ring_buffer_align_ctx(ctx, alignment);
	lib_ring_buffer_write(&client_config, ctx, src, len);
}

static
void lttng_event_write_from_user(struct lttng_kernel_ring_buffer_ctx *ctx,
			       const void __user *src, size_t len, size_t alignment)
{
	lib_ring_buffer_align_ctx(ctx, alignment);
	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
}

static
void lttng_event_memset(struct lttng_kernel_ring_buffer_ctx *ctx,
		int c, size_t len)
{
	lib_ring_buffer_memset(&client_config, ctx, c, len);
}

static
void lttng_event_strcpy(struct lttng_kernel_ring_buffer_ctx *ctx, const char *src,
		size_t len)
{
	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
}

static
void lttng_event_pstrcpy_pad(struct lttng_kernel_ring_buffer_ctx *ctx, const char *src,
		size_t len)
{
	lib_ring_buffer_pstrcpy(&client_config, ctx, src, len, '\0');
}

static
size_t lttng_packet_avail_size(struct lttng_kernel_ring_buffer_channel *chan)
{
	unsigned long o_begin;
	struct lttng_kernel_ring_buffer *buf;

	buf = chan->backend.buf;	/* 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);
	}
}

static
wait_queue_head_t *lttng_get_writer_buf_wait_queue(struct lttng_kernel_ring_buffer_channel *chan, int cpu)
{
	struct lttng_kernel_ring_buffer *buf = channel_get_ring_buffer(&client_config,
					chan, cpu);
	return &buf->write_wait;
}

static
wait_queue_head_t *lttng_get_hp_wait_queue(struct lttng_kernel_ring_buffer_channel *chan)
{
	return &chan->hp_wait;
}

static
int lttng_is_finalized(struct lttng_kernel_ring_buffer_channel *chan)
{
	return lib_ring_buffer_channel_is_finalized(chan);
}

static
int lttng_is_disabled(struct lttng_kernel_ring_buffer_channel *chan)
{
	return lib_ring_buffer_channel_is_disabled(chan);
}

static struct lttng_transport lttng_relay_transport = {
	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	.owner = THIS_MODULE,
	.ops = {
		.priv = __LTTNG_COMPOUND_LITERAL(struct lttng_kernel_channel_buffer_ops_private, {
			.pub = &lttng_relay_transport.ops,
			.channel_create = _channel_create,
			.channel_destroy = lttng_channel_destroy,
			.buffer_read_open = lttng_buffer_read_open,
			.buffer_has_read_closed_stream =
				lttng_buffer_has_read_closed_stream,
			.buffer_read_close = lttng_buffer_read_close,
			.packet_avail_size = lttng_packet_avail_size,
			.get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue,
			.get_hp_wait_queue = lttng_get_hp_wait_queue,
			.is_finalized = lttng_is_finalized,
			.is_disabled = lttng_is_disabled,
			.timestamp_begin = client_timestamp_begin,
			.timestamp_end = client_timestamp_end,
			.events_discarded = client_events_discarded,
			.content_size = client_content_size,
			.packet_size = client_packet_size,
			.stream_id = client_stream_id,
			.current_timestamp = client_current_timestamp,
			.sequence_number = client_sequence_number,
			.instance_id = client_instance_id,
		}),
		.event_reserve = lttng_event_reserve,
		.event_commit = lttng_event_commit,
		.event_write_from_user = lttng_event_write_from_user,
		.event_memset = lttng_event_memset,
		.event_write = lttng_event_write,
		.event_strcpy = lttng_event_strcpy,
		.event_pstrcpy_pad = lttng_event_pstrcpy_pad,
	},
};

static int __init lttng_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_mappings();
	lttng_transport_register(&lttng_relay_transport);
	return 0;
}

module_init(lttng_ring_buffer_client_init);

static void __exit lttng_ring_buffer_client_exit(void)
{
	lttng_transport_unregister(&lttng_relay_transport);
}

module_exit(lttng_ring_buffer_client_exit);

MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
		   " client");
MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
	LTTNG_MODULES_EXTRAVERSION);
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed	2	*
a90917c3	3	* lttng-ring-buffer-client.h
881833e3	4	*
881833e3 MD	5	* LTTng lib ring buffer client template.
881833e3 MD	6	*
886d51a3	7	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
881833e3 MD	8	*/
	9
	10	#include <linux/module.h>
	11	#include <linux/types.h>
263b6c88	12	#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
2df37e95	13	#include <lttng/events.h>
e8c0bbd3	14	#include <lttng/events-internal.h>
2df37e95	15	#include <lttng/tracer.h>
881833e3	16
dd5a0db3 MD	17	static struct lttng_transport lttng_relay_transport;
dd5a0db3 MD	18
881833e3 MD	19	struct metadata_packet_header {
881833e3 MD	20	uint32_t magic; /* 0x75D11D57 */
1ec3f75a	21	uint8_t uuid[16]; /* Unique Universal Identifier */
881833e3 MD	22	uint32_t checksum; /* 0 if unused */
	23	uint32_t content_size; /* in bits */
	24	uint32_t packet_size; /* in bits */
	25	uint8_t compression_scheme; /* 0 if unused */
	26	uint8_t encryption_scheme; /* 0 if unused */
	27	uint8_t checksum_scheme; /* 0 if unused */
4173df96 MD	28	uint8_t major; /* CTF spec major version number */
4173df96 MD	29	uint8_t minor; /* CTF spec minor version number */
881833e3 MD	30	uint8_t header_end[0];
	31	};
	32
	33	struct metadata_record_header {
	34	uint8_t header_end[0]; /* End of header */
	35	};
	36
e20c0fec	37	static const struct lttng_kernel_ring_buffer_config client_config;
881833e3 MD	38
881833e3 MD	39	static inline
860c213b	40	u64 lib_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
881833e3 MD	41	{
	42	return 0;
	43	}
	44
	45	static inline
e20c0fec	46	size_t record_header_size(const struct lttng_kernel_ring_buffer_config *config,
860c213b	47	struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
64c796d8	48	size_t *pre_header_padding,
8a57ec02	49	struct lttng_kernel_ring_buffer_ctx *ctx,
cc62f29e	50	void *client_ctx)
881833e3 MD	51	{
	52	return 0;
	53	}
	54
24591303	55	#include <ringbuffer/api.h>
881833e3	56
860c213b	57	static u64 client_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
881833e3 MD	58	{
	59	return 0;
	60	}
	61
	62	static
e20c0fec	63	size_t client_record_header_size(const struct lttng_kernel_ring_buffer_config *config,
860c213b	64	struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
881833e3	65	size_t *pre_header_padding,
8a57ec02	66	struct lttng_kernel_ring_buffer_ctx *ctx,
cc62f29e	67	void *client_ctx)
881833e3 MD	68	{
	69	return 0;
	70	}
	71
	72	/**
	73	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	74	*
	75	* Return header size without padding after the structure. Don't use packed
	76	* structure because gcc generates inefficient code on some architectures
	77	* (powerpc, mips..)
	78	*/
	79	static size_t client_packet_header_size(void)
	80	{
	81	return offsetof(struct metadata_packet_header, header_end);
	82	}
	83
e20c0fec	84	static void client_buffer_begin(struct lttng_kernel_ring_buffer *buf, u64 tsc,
881833e3 MD	85	unsigned int subbuf_idx)
881833e3 MD	86	{
860c213b	87	struct lttng_kernel_ring_buffer_channel *chan = buf->backend.chan;
881833e3 MD	88	struct metadata_packet_header *header =
	89	(struct metadata_packet_header *)
	90	lib_ring_buffer_offset_address(&buf->backend,
	91	subbuf_idx * chan->backend.subbuf_size);
a36580d5 MD	92	struct lttng_metadata_cache *metadata_cache =
a36580d5 MD	93	channel_get_private(chan);
881833e3 MD	94
881833e3 MD	95	header->magic = TSDL_MAGIC_NUMBER;
a36580d5 MD	96	memcpy(header->uuid, metadata_cache->uuid.b,
a36580d5 MD	97	sizeof(metadata_cache->uuid));
881833e3 MD	98	header->checksum = 0; /* 0 if unused */
	99	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	100	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	101	header->compression_scheme = 0; /* 0 if unused */
	102	header->encryption_scheme = 0; /* 0 if unused */
	103	header->checksum_scheme = 0; /* 0 if unused */
4173df96 MD	104	header->major = CTF_SPEC_MAJOR;
4173df96 MD	105	header->minor = CTF_SPEC_MINOR;
881833e3 MD	106	}
	107
	108	/*
	109	* offset is assumed to never be 0 here : never deliver a completely empty
	110	* subbuffer. data_size is between 1 and subbuf_size.
	111	*/
e20c0fec	112	static void client_buffer_end(struct lttng_kernel_ring_buffer *buf, u64 tsc,
b2cf5e0b MD	113	unsigned int subbuf_idx, unsigned long data_size,
b2cf5e0b MD	114	const struct lttng_kernel_ring_buffer_ctx *ctx)
881833e3	115	{
860c213b	116	struct lttng_kernel_ring_buffer_channel *chan = buf->backend.chan;
d793d5e1	117	struct metadata_packet_header *header =
1ec3f75a	118	(struct metadata_packet_header *)
881833e3 MD	119	lib_ring_buffer_offset_address(&buf->backend,
	120	subbuf_idx * chan->backend.subbuf_size);
	121	unsigned long records_lost = 0;
	122
	123	header->content_size = data_size * CHAR_BIT; /* in bits */
	124	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
71c1d843 MD	125	/*
	126	* We do not care about the records lost count, because the metadata
	127	* channel waits and retry.
	128	*/
b2cf5e0b MD	129	(void) lib_ring_buffer_get_records_lost_full(&client_config, ctx);
	130	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, ctx);
	131	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, ctx);
881833e3 MD	132	WARN_ON_ONCE(records_lost != 0);
	133	}
	134
e20c0fec	135	static int client_buffer_create(struct lttng_kernel_ring_buffer buf, void priv,
881833e3 MD	136	int cpu, const char *name)
	137	{
	138	return 0;
	139	}
	140
e20c0fec	141	static void client_buffer_finalize(struct lttng_kernel_ring_buffer buf, void priv, int cpu)
881833e3 MD	142	{
	143	}
	144
e20c0fec MD	145	static int client_timestamp_begin(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	146	struct lttng_kernel_ring_buffer buf, uint64_t timestamp_begin)
3b731ab1 JD	147	{
	148	return -ENOSYS;
	149	}
	150
e20c0fec MD	151	static int client_timestamp_end(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	152	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	153	uint64_t *timestamp_end)
	154	{
	155	return -ENOSYS;
	156	}
	157
e20c0fec MD	158	static int client_events_discarded(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	159	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	160	uint64_t *events_discarded)
	161	{
	162	return -ENOSYS;
	163	}
	164
e20c0fec MD	165	static int client_current_timestamp(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	166	struct lttng_kernel_ring_buffer *bufb,
2348ca17 JD	167	uint64_t *ts)
	168	{
	169	return -ENOSYS;
	170	}
	171
e20c0fec MD	172	static int client_content_size(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	173	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	174	uint64_t *content_size)
	175	{
	176	return -ENOSYS;
	177	}
	178
e20c0fec MD	179	static int client_packet_size(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	180	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	181	uint64_t *packet_size)
	182	{
	183	return -ENOSYS;
	184	}
	185
e20c0fec MD	186	static int client_stream_id(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	187	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	188	uint64_t *stream_id)
	189	{
	190	return -ENOSYS;
	191	}
	192
e20c0fec MD	193	static int client_sequence_number(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	194	struct lttng_kernel_ring_buffer *bufb,
5b3cf4f9 JD	195	uint64_t *seq)
	196	{
	197	return -ENOSYS;
	198	}
	199
5594698f	200	static
e20c0fec MD	201	int client_instance_id(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	202	struct lttng_kernel_ring_buffer *bufb,
5594698f JD	203	uint64_t *id)
	204	{
	205	return -ENOSYS;
	206	}
	207
e20c0fec	208	static const struct lttng_kernel_ring_buffer_config client_config = {
881833e3 MD	209	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	210	.cb.record_header_size = client_record_header_size,
	211	.cb.subbuffer_header_size = client_packet_header_size,
	212	.cb.buffer_begin = client_buffer_begin,
	213	.cb.buffer_end = client_buffer_end,
	214	.cb.buffer_create = client_buffer_create,
	215	.cb.buffer_finalize = client_buffer_finalize,
	216
	217	.tsc_bits = 0,
	218	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	219	.sync = RING_BUFFER_SYNC_GLOBAL,
	220	.mode = RING_BUFFER_MODE_TEMPLATE,
	221	.backend = RING_BUFFER_PAGE,
2db1399a	222	.output = RING_BUFFER_OUTPUT_TEMPLATE,
881833e3 MD	223	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	224	.ipi = RING_BUFFER_IPI_BARRIER,
	225	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
	226	};
	227
dd5a0db3 MD	228	static
	229	void release_priv_ops(void *priv_ops)
	230	{
	231	module_put(THIS_MODULE);
	232	}
	233
	234	static
860c213b	235	void lttng_channel_destroy(struct lttng_kernel_ring_buffer_channel *chan)
dd5a0db3 MD	236	{
	237	channel_destroy(chan);
	238	}
	239
881833e3	240	static
860c213b	241	struct lttng_kernel_ring_buffer_channel _channel_create(const char name,
5cf4b87c	242	void priv, void buf_addr,
881833e3 MD	243	size_t subbuf_size, size_t num_subbuf,
	244	unsigned int switch_timer_interval,
	245	unsigned int read_timer_interval)
	246	{
f7d06400	247	struct lttng_kernel_channel_buffer *lttng_chan = priv;
860c213b	248	struct lttng_kernel_ring_buffer_channel *chan;
dd5a0db3	249
a36580d5	250	chan = channel_create(&client_config, name,
f7d06400	251	lttng_chan->parent.session->priv->metadata_cache, buf_addr,
881833e3 MD	252	subbuf_size, num_subbuf, switch_timer_interval,
881833e3 MD	253	read_timer_interval);
dd5a0db3 MD	254	if (chan) {
	255	/*
	256	* Ensure this module is not unloaded before we finish
	257	* using lttng_relay_transport.ops.
	258	*/
	259	if (!try_module_get(THIS_MODULE)) {
5a15f70c	260	printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
dd5a0db3 MD	261	goto error;
	262	}
	263	chan->backend.priv_ops = &lttng_relay_transport.ops;
	264	chan->backend.release_priv_ops = release_priv_ops;
	265	}
	266	return chan;
881833e3	267
dd5a0db3 MD	268	error:
	269	lttng_channel_destroy(chan);
	270	return NULL;
881833e3 MD	271	}
	272
	273	static
e20c0fec	274	struct lttng_kernel_ring_buffer lttng_buffer_read_open(struct lttng_kernel_ring_buffer_channel chan)
881833e3	275	{
e20c0fec	276	struct lttng_kernel_ring_buffer *buf;
881833e3	277
cd4bd11f MD	278	buf = channel_get_ring_buffer(&client_config, chan, 0);
	279	if (!lib_ring_buffer_open_read(buf))
	280	return buf;
881833e3 MD	281	return NULL;
	282	}
	283
f71ecafa	284	static
860c213b	285	int lttng_buffer_has_read_closed_stream(struct lttng_kernel_ring_buffer_channel *chan)
f71ecafa	286	{
e20c0fec	287	struct lttng_kernel_ring_buffer *buf;
f71ecafa MD	288	int cpu;
	289
	290	for_each_channel_cpu(cpu, chan) {
	291	buf = channel_get_ring_buffer(&client_config, chan, cpu);
	292	if (!atomic_long_read(&buf->active_readers))
	293	return 1;
	294	}
	295	return 0;
	296	}
	297
881833e3	298	static
e20c0fec	299	void lttng_buffer_read_close(struct lttng_kernel_ring_buffer *buf)
881833e3 MD	300	{
881833e3 MD	301	lib_ring_buffer_release_read(buf);
881833e3 MD	302	}
881833e3 MD	303
c099397a	304	static
8a57ec02	305	int lttng_event_reserve(struct lttng_kernel_ring_buffer_ctx *ctx)
881833e3	306	{
860c213b	307	struct lttng_kernel_ring_buffer_channel *chan = ctx->client_priv;
85a07c33 MD	308	int ret;
85a07c33 MD	309
b1199bd3 MD	310	memset(&ctx->priv, 0, sizeof(ctx->priv));
	311	ctx->priv.chan = chan;
	312
cc62f29e	313	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
85a07c33 MD	314	if (ret)
	315	return ret;
	316	lib_ring_buffer_backend_get_pages(&client_config, ctx,
b1199bd3	317	&ctx->priv.backend_pages);
85a07c33 MD	318	return 0;
85a07c33 MD	319
881833e3 MD	320	}
881833e3 MD	321
c099397a	322	static
8a57ec02	323	void lttng_event_commit(struct lttng_kernel_ring_buffer_ctx *ctx)
881833e3 MD	324	{
	325	lib_ring_buffer_commit(&client_config, ctx);
	326	}
	327
c099397a	328	static
8a57ec02	329	void lttng_event_write(struct lttng_kernel_ring_buffer_ctx ctx, const void src,
f5ffbd77	330	size_t len, size_t alignment)
881833e3	331	{
f5ffbd77	332	lib_ring_buffer_align_ctx(ctx, alignment);
881833e3 MD	333	lib_ring_buffer_write(&client_config, ctx, src, len);
	334	}
	335
4ea00e4f	336	static
8a57ec02	337	void lttng_event_write_from_user(struct lttng_kernel_ring_buffer_ctx *ctx,
f5ffbd77	338	const void __user *src, size_t len, size_t alignment)
4ea00e4f	339	{
f5ffbd77	340	lib_ring_buffer_align_ctx(ctx, alignment);
7b8ea3a5	341	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
4ea00e4f JD	342	}
4ea00e4f JD	343
58aa5d24	344	static
8a57ec02	345	void lttng_event_memset(struct lttng_kernel_ring_buffer_ctx *ctx,
58aa5d24 MD	346	int c, size_t len)
	347	{
	348	lib_ring_buffer_memset(&client_config, ctx, c, len);
	349	}
	350
16f78f3a	351	static
8a57ec02	352	void lttng_event_strcpy(struct lttng_kernel_ring_buffer_ctx ctx, const char src,
16f78f3a MD	353	size_t len)
	354	{
	355	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
	356	}
	357
0d1080f4 MD	358	static
	359	void lttng_event_pstrcpy_pad(struct lttng_kernel_ring_buffer_ctx ctx, const char src,
	360	size_t len)
	361	{
	362	lib_ring_buffer_pstrcpy(&client_config, ctx, src, len, '\0');
	363	}
	364
1ec3f75a	365	static
860c213b	366	size_t lttng_packet_avail_size(struct lttng_kernel_ring_buffer_channel *chan)
1ec3f75a MD	367	{
1ec3f75a MD	368	unsigned long o_begin;
e20c0fec	369	struct lttng_kernel_ring_buffer *buf;
1ec3f75a MD	370
	371	buf = chan->backend.buf; /* Only for global buffer ! */
	372	o_begin = v_read(&client_config, &buf->offset);
	373	if (subbuf_offset(o_begin, chan) != 0) {
	374	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	375	} else {
	376	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	377	- sizeof(struct metadata_packet_header);
	378	}
	379	}
	380
c099397a	381	static
860c213b	382	wait_queue_head_t lttng_get_writer_buf_wait_queue(struct lttng_kernel_ring_buffer_channel chan, int cpu)
c099397a	383	{
e20c0fec	384	struct lttng_kernel_ring_buffer *buf = channel_get_ring_buffer(&client_config,
71c1d843 MD	385	chan, cpu);
71c1d843 MD	386	return &buf->write_wait;
24cedcfe MD	387	}
	388
	389	static
860c213b	390	wait_queue_head_t lttng_get_hp_wait_queue(struct lttng_kernel_ring_buffer_channel chan)
24cedcfe MD	391	{
	392	return &chan->hp_wait;
	393	}
	394
	395	static
860c213b	396	int lttng_is_finalized(struct lttng_kernel_ring_buffer_channel *chan)
24cedcfe MD	397	{
24cedcfe MD	398	return lib_ring_buffer_channel_is_finalized(chan);
c099397a MD	399	}
c099397a MD	400
254ec7bc	401	static
860c213b	402	int lttng_is_disabled(struct lttng_kernel_ring_buffer_channel *chan)
254ec7bc MD	403	{
	404	return lib_ring_buffer_channel_is_disabled(chan);
	405	}
	406
a90917c3	407	static struct lttng_transport lttng_relay_transport = {
881833e3 MD	408	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	409	.owner = THIS_MODULE,
	410	.ops = {
4a399b76 MD	411	.priv = __LTTNG_COMPOUND_LITERAL(struct lttng_kernel_channel_buffer_ops_private, {
	412	.pub = &lttng_relay_transport.ops,
	413	.channel_create = _channel_create,
	414	.channel_destroy = lttng_channel_destroy,
	415	.buffer_read_open = lttng_buffer_read_open,
	416	.buffer_has_read_closed_stream =
	417	lttng_buffer_has_read_closed_stream,
	418	.buffer_read_close = lttng_buffer_read_close,
	419	.packet_avail_size = lttng_packet_avail_size,
	420	.get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue,
	421	.get_hp_wait_queue = lttng_get_hp_wait_queue,
	422	.is_finalized = lttng_is_finalized,
	423	.is_disabled = lttng_is_disabled,
	424	.timestamp_begin = client_timestamp_begin,
	425	.timestamp_end = client_timestamp_end,
	426	.events_discarded = client_events_discarded,
	427	.content_size = client_content_size,
	428	.packet_size = client_packet_size,
	429	.stream_id = client_stream_id,
	430	.current_timestamp = client_current_timestamp,
	431	.sequence_number = client_sequence_number,
	432	.instance_id = client_instance_id,
	433	}),
a90917c3 MD	434	.event_reserve = lttng_event_reserve,
	435	.event_commit = lttng_event_commit,
	436	.event_write_from_user = lttng_event_write_from_user,
	437	.event_memset = lttng_event_memset,
	438	.event_write = lttng_event_write,
16f78f3a	439	.event_strcpy = lttng_event_strcpy,
0d1080f4	440	.event_pstrcpy_pad = lttng_event_pstrcpy_pad,
881833e3 MD	441	},
	442	};
	443
a90917c3	444	static int __init lttng_ring_buffer_client_init(void)
881833e3 MD	445	{
	446	/*
	447	* This vmalloc sync all also takes care of the lib ring buffer
	448	* vmalloc'd module pages when it is built as a module into LTTng.
	449	*/
263b6c88	450	wrapper_vmalloc_sync_mappings();
a90917c3	451	lttng_transport_register(&lttng_relay_transport);
881833e3 MD	452	return 0;
	453	}
	454
a90917c3	455	module_init(lttng_ring_buffer_client_init);
881833e3	456
a90917c3	457	static void __exit lttng_ring_buffer_client_exit(void)
881833e3	458	{
a90917c3	459	lttng_transport_unregister(&lttng_relay_transport);
881833e3 MD	460	}
881833e3 MD	461
a90917c3	462	module_exit(lttng_ring_buffer_client_exit);
881833e3 MD	463
881833e3 MD	464	MODULE_LICENSE("GPL and additional rights");
1c124020	465	MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
881833e3 MD	466	MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
881833e3 MD	467	" client");
1c124020 MJ	468	MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
	469	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
	470	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
	471	LTTNG_MODULES_EXTRAVERSION);