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

/*
 * lttng-ring-buffer-client.h
 *
 * LTTng lib ring buffer client template.
 *
 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; only
 * version 2.1 of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <linux/module.h>
#include <linux/types.h>
#include <wrapper/vmalloc.h>	/* for wrapper_vmalloc_sync_all() */
#include <lttng-events.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 lib_ring_buffer_config client_config;

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

static inline
size_t 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 0;
}

#include <wrapper/ringbuffer/api.h>

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

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 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 lib_ring_buffer *buf, u64 tsc,
				unsigned int subbuf_idx)
{
	struct 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 lib_ring_buffer *buf, u64 tsc,
			      unsigned int subbuf_idx, unsigned long data_size)
{
	struct 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, buf);
	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	WARN_ON_ONCE(records_lost != 0);
}

static int client_buffer_create(struct 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 int client_timestamp_begin(const struct lib_ring_buffer_config *config,
		struct lib_ring_buffer *buf, uint64_t *timestamp_begin)
{
	return -ENOSYS;
}

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

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

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

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

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

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

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

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

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 = 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 channel *chan)
{
	channel_destroy(chan);
}

static
struct channel *_channel_create(const char *name,
				struct lttng_channel *lttng_chan, void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval)
{
	struct channel *chan;

	chan = channel_create(&client_config, name,
			      lttng_chan->session->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 "LTT : 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 lib_ring_buffer *lttng_buffer_read_open(struct channel *chan)
{
	struct lib_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 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 (!atomic_long_read(&buf->active_readers))
			return 1;
	}
	return 0;
}

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

static
int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id)
{
	int ret;

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

}

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

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

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

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

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

static
size_t lttng_packet_avail_size(struct channel *chan)
			     
{
	unsigned long o_begin;
	struct lib_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 channel *chan, int cpu)
{
	struct lib_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 channel *chan)
{
	return &chan->hp_wait;
}

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

static
int lttng_is_disabled(struct 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 = {
		.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,
		.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,
		.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,
	},
};

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_all();
	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");
MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
		   " client");
Commit	Line	Data
881833e3	1	/*
a90917c3	2	* lttng-ring-buffer-client.h
881833e3	3	*
881833e3 MD	4	* LTTng lib ring buffer client template.
881833e3 MD	5	*
886d51a3 MD	6	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
	10	* License as published by the Free Software Foundation; only
	11	* version 2.1 of the License.
	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
881833e3 MD	21	*/
	22
	23	#include <linux/module.h>
	24	#include <linux/types.h>
bbd023d6 MD	25	#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_all() */
	26	#include <lttng-events.h>
	27	#include <lttng-tracer.h>
881833e3	28
dd5a0db3 MD	29	static struct lttng_transport lttng_relay_transport;
dd5a0db3 MD	30
881833e3 MD	31	struct metadata_packet_header {
881833e3 MD	32	uint32_t magic; /* 0x75D11D57 */
1ec3f75a	33	uint8_t uuid[16]; /* Unique Universal Identifier */
881833e3 MD	34	uint32_t checksum; /* 0 if unused */
	35	uint32_t content_size; /* in bits */
	36	uint32_t packet_size; /* in bits */
	37	uint8_t compression_scheme; /* 0 if unused */
	38	uint8_t encryption_scheme; /* 0 if unused */
	39	uint8_t checksum_scheme; /* 0 if unused */
4173df96 MD	40	uint8_t major; /* CTF spec major version number */
4173df96 MD	41	uint8_t minor; /* CTF spec minor version number */
881833e3 MD	42	uint8_t header_end[0];
	43	};
	44
	45	struct metadata_record_header {
	46	uint8_t header_end[0]; /* End of header */
	47	};
	48
	49	static const struct lib_ring_buffer_config client_config;
	50
	51	static inline
	52	u64 lib_ring_buffer_clock_read(struct channel *chan)
	53	{
	54	return 0;
	55	}
	56
	57	static inline
c1cc82b8	58	size_t record_header_size(const struct lib_ring_buffer_config *config,
881833e3	59	struct channel *chan, size_t offset,
64c796d8	60	size_t *pre_header_padding,
881833e3 MD	61	struct lib_ring_buffer_ctx *ctx)
	62	{
	63	return 0;
	64	}
	65
bbd023d6	66	#include <wrapper/ringbuffer/api.h>
881833e3 MD	67
	68	static u64 client_ring_buffer_clock_read(struct channel *chan)
	69	{
	70	return 0;
	71	}
	72
	73	static
	74	size_t client_record_header_size(const struct lib_ring_buffer_config *config,
	75	struct channel *chan, size_t offset,
881833e3	76	size_t *pre_header_padding,
881833e3 MD	77	struct lib_ring_buffer_ctx *ctx)
	78	{
	79	return 0;
	80	}
	81
	82	/**
	83	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	84	*
	85	* Return header size without padding after the structure. Don't use packed
	86	* structure because gcc generates inefficient code on some architectures
	87	* (powerpc, mips..)
	88	*/
	89	static size_t client_packet_header_size(void)
	90	{
	91	return offsetof(struct metadata_packet_header, header_end);
	92	}
	93
	94	static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
	95	unsigned int subbuf_idx)
	96	{
	97	struct channel *chan = buf->backend.chan;
	98	struct metadata_packet_header *header =
	99	(struct metadata_packet_header *)
	100	lib_ring_buffer_offset_address(&buf->backend,
	101	subbuf_idx * chan->backend.subbuf_size);
a36580d5 MD	102	struct lttng_metadata_cache *metadata_cache =
a36580d5 MD	103	channel_get_private(chan);
881833e3 MD	104
881833e3 MD	105	header->magic = TSDL_MAGIC_NUMBER;
a36580d5 MD	106	memcpy(header->uuid, metadata_cache->uuid.b,
a36580d5 MD	107	sizeof(metadata_cache->uuid));
881833e3 MD	108	header->checksum = 0; /* 0 if unused */
	109	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	110	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	111	header->compression_scheme = 0; /* 0 if unused */
	112	header->encryption_scheme = 0; /* 0 if unused */
	113	header->checksum_scheme = 0; /* 0 if unused */
4173df96 MD	114	header->major = CTF_SPEC_MAJOR;
4173df96 MD	115	header->minor = CTF_SPEC_MINOR;
881833e3 MD	116	}
	117
	118	/*
	119	* offset is assumed to never be 0 here : never deliver a completely empty
	120	* subbuffer. data_size is between 1 and subbuf_size.
	121	*/
	122	static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
	123	unsigned int subbuf_idx, unsigned long data_size)
	124	{
	125	struct channel *chan = buf->backend.chan;
d793d5e1	126	struct metadata_packet_header *header =
1ec3f75a	127	(struct metadata_packet_header *)
881833e3 MD	128	lib_ring_buffer_offset_address(&buf->backend,
	129	subbuf_idx * chan->backend.subbuf_size);
	130	unsigned long records_lost = 0;
	131
	132	header->content_size = data_size * CHAR_BIT; /* in bits */
	133	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
71c1d843 MD	134	/*
	135	* We do not care about the records lost count, because the metadata
	136	* channel waits and retry.
	137	*/
	138	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
881833e3 MD	139	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	140	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	141	WARN_ON_ONCE(records_lost != 0);
	142	}
	143
	144	static int client_buffer_create(struct lib_ring_buffer buf, void priv,
	145	int cpu, const char *name)
	146	{
	147	return 0;
	148	}
	149
	150	static void client_buffer_finalize(struct lib_ring_buffer buf, void priv, int cpu)
	151	{
	152	}
	153
3b731ab1 JD	154	static int client_timestamp_begin(const struct lib_ring_buffer_config *config,
	155	struct lib_ring_buffer buf, uint64_t timestamp_begin)
	156	{
	157	return -ENOSYS;
	158	}
	159
	160	static int client_timestamp_end(const struct lib_ring_buffer_config *config,
	161	struct lib_ring_buffer *bufb,
	162	uint64_t *timestamp_end)
	163	{
	164	return -ENOSYS;
	165	}
	166
	167	static int client_events_discarded(const struct lib_ring_buffer_config *config,
	168	struct lib_ring_buffer *bufb,
	169	uint64_t *events_discarded)
	170	{
	171	return -ENOSYS;
	172	}
	173
2348ca17 JD	174	static int client_current_timestamp(const struct lib_ring_buffer_config *config,
	175	struct lib_ring_buffer *bufb,
	176	uint64_t *ts)
	177	{
	178	return -ENOSYS;
	179	}
	180
3b731ab1 JD	181	static int client_content_size(const struct lib_ring_buffer_config *config,
	182	struct lib_ring_buffer *bufb,
	183	uint64_t *content_size)
	184	{
	185	return -ENOSYS;
	186	}
	187
	188	static int client_packet_size(const struct lib_ring_buffer_config *config,
	189	struct lib_ring_buffer *bufb,
	190	uint64_t *packet_size)
	191	{
	192	return -ENOSYS;
	193	}
	194
	195	static int client_stream_id(const struct lib_ring_buffer_config *config,
	196	struct lib_ring_buffer *bufb,
	197	uint64_t *stream_id)
	198	{
	199	return -ENOSYS;
	200	}
	201
5b3cf4f9 JD	202	static int client_sequence_number(const struct lib_ring_buffer_config *config,
	203	struct lib_ring_buffer *bufb,
	204	uint64_t *seq)
	205	{
	206	return -ENOSYS;
	207	}
	208
5594698f JD	209	static
	210	int client_instance_id(const struct lib_ring_buffer_config *config,
	211	struct lib_ring_buffer *bufb,
	212	uint64_t *id)
	213	{
	214	return -ENOSYS;
	215	}
	216
881833e3 MD	217	static const struct lib_ring_buffer_config client_config = {
	218	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	219	.cb.record_header_size = client_record_header_size,
	220	.cb.subbuffer_header_size = client_packet_header_size,
	221	.cb.buffer_begin = client_buffer_begin,
	222	.cb.buffer_end = client_buffer_end,
	223	.cb.buffer_create = client_buffer_create,
	224	.cb.buffer_finalize = client_buffer_finalize,
	225
	226	.tsc_bits = 0,
	227	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	228	.sync = RING_BUFFER_SYNC_GLOBAL,
	229	.mode = RING_BUFFER_MODE_TEMPLATE,
	230	.backend = RING_BUFFER_PAGE,
2db1399a	231	.output = RING_BUFFER_OUTPUT_TEMPLATE,
881833e3 MD	232	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	233	.ipi = RING_BUFFER_IPI_BARRIER,
	234	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
	235	};
	236
dd5a0db3 MD	237	static
	238	void release_priv_ops(void *priv_ops)
	239	{
	240	module_put(THIS_MODULE);
	241	}
	242
	243	static
	244	void lttng_channel_destroy(struct channel *chan)
	245	{
	246	channel_destroy(chan);
	247	}
	248
881833e3 MD	249	static
881833e3 MD	250	struct channel _channel_create(const char name,
a90917c3	251	struct lttng_channel lttng_chan, void buf_addr,
881833e3 MD	252	size_t subbuf_size, size_t num_subbuf,
	253	unsigned int switch_timer_interval,
	254	unsigned int read_timer_interval)
	255	{
dd5a0db3 MD	256	struct channel *chan;
dd5a0db3 MD	257
a36580d5 MD	258	chan = channel_create(&client_config, name,
a36580d5 MD	259	lttng_chan->session->metadata_cache, buf_addr,
881833e3 MD	260	subbuf_size, num_subbuf, switch_timer_interval,
881833e3 MD	261	read_timer_interval);
dd5a0db3 MD	262	if (chan) {
	263	/*
	264	* Ensure this module is not unloaded before we finish
	265	* using lttng_relay_transport.ops.
	266	*/
	267	if (!try_module_get(THIS_MODULE)) {
	268	printk(KERN_WARNING "LTT : Can't lock transport module.\n");
	269	goto error;
	270	}
	271	chan->backend.priv_ops = &lttng_relay_transport.ops;
	272	chan->backend.release_priv_ops = release_priv_ops;
	273	}
	274	return chan;
881833e3	275
dd5a0db3 MD	276	error:
	277	lttng_channel_destroy(chan);
	278	return NULL;
881833e3 MD	279	}
	280
	281	static
a90917c3	282	struct lib_ring_buffer lttng_buffer_read_open(struct channel chan)
881833e3 MD	283	{
881833e3 MD	284	struct lib_ring_buffer *buf;
881833e3	285
cd4bd11f MD	286	buf = channel_get_ring_buffer(&client_config, chan, 0);
	287	if (!lib_ring_buffer_open_read(buf))
	288	return buf;
881833e3 MD	289	return NULL;
	290	}
	291
f71ecafa	292	static
a90917c3	293	int lttng_buffer_has_read_closed_stream(struct channel *chan)
f71ecafa MD	294	{
	295	struct lib_ring_buffer *buf;
	296	int cpu;
	297
	298	for_each_channel_cpu(cpu, chan) {
	299	buf = channel_get_ring_buffer(&client_config, chan, cpu);
	300	if (!atomic_long_read(&buf->active_readers))
	301	return 1;
	302	}
	303	return 0;
	304	}
	305
881833e3	306	static
a90917c3	307	void lttng_buffer_read_close(struct lib_ring_buffer *buf)
881833e3 MD	308	{
881833e3 MD	309	lib_ring_buffer_release_read(buf);
881833e3 MD	310	}
881833e3 MD	311
c099397a	312	static
a90917c3	313	int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id)
881833e3	314	{
85a07c33 MD	315	int ret;
	316
	317	ret = lib_ring_buffer_reserve(&client_config, ctx);
	318	if (ret)
	319	return ret;
	320	lib_ring_buffer_backend_get_pages(&client_config, ctx,
	321	&ctx->backend_pages);
	322	return 0;
	323
881833e3 MD	324	}
881833e3 MD	325
c099397a	326	static
a90917c3	327	void lttng_event_commit(struct lib_ring_buffer_ctx *ctx)
881833e3 MD	328	{
	329	lib_ring_buffer_commit(&client_config, ctx);
	330	}
	331
c099397a	332	static
a90917c3	333	void lttng_event_write(struct lib_ring_buffer_ctx ctx, const void src,
881833e3 MD	334	size_t len)
	335	{
	336	lib_ring_buffer_write(&client_config, ctx, src, len);
	337	}
	338
4ea00e4f	339	static
a90917c3	340	void lttng_event_write_from_user(struct lib_ring_buffer_ctx *ctx,
4ea00e4f JD	341	const void __user *src, size_t len)
4ea00e4f JD	342	{
7b8ea3a5	343	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
4ea00e4f JD	344	}
4ea00e4f JD	345
58aa5d24	346	static
a90917c3	347	void lttng_event_memset(struct lib_ring_buffer_ctx *ctx,
58aa5d24 MD	348	int c, size_t len)
	349	{
	350	lib_ring_buffer_memset(&client_config, ctx, c, len);
	351	}
	352
16f78f3a MD	353	static
	354	void lttng_event_strcpy(struct lib_ring_buffer_ctx ctx, const char src,
	355	size_t len)
	356	{
	357	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
	358	}
	359
1ec3f75a	360	static
a90917c3	361	size_t lttng_packet_avail_size(struct channel *chan)
1ec3f75a MD	362
	363	{
	364	unsigned long o_begin;
	365	struct lib_ring_buffer *buf;
	366
	367	buf = chan->backend.buf; /* Only for global buffer ! */
	368	o_begin = v_read(&client_config, &buf->offset);
	369	if (subbuf_offset(o_begin, chan) != 0) {
	370	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	371	} else {
	372	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	373	- sizeof(struct metadata_packet_header);
	374	}
	375	}
	376
c099397a	377	static
a90917c3	378	wait_queue_head_t lttng_get_writer_buf_wait_queue(struct channel chan, int cpu)
c099397a	379	{
71c1d843 MD	380	struct lib_ring_buffer *buf = channel_get_ring_buffer(&client_config,
	381	chan, cpu);
	382	return &buf->write_wait;
24cedcfe MD	383	}
	384
	385	static
a90917c3	386	wait_queue_head_t lttng_get_hp_wait_queue(struct channel chan)
24cedcfe MD	387	{
	388	return &chan->hp_wait;
	389	}
	390
	391	static
a90917c3	392	int lttng_is_finalized(struct channel *chan)
24cedcfe MD	393	{
24cedcfe MD	394	return lib_ring_buffer_channel_is_finalized(chan);
c099397a MD	395	}
c099397a MD	396
254ec7bc	397	static
a90917c3	398	int lttng_is_disabled(struct channel *chan)
254ec7bc MD	399	{
	400	return lib_ring_buffer_channel_is_disabled(chan);
	401	}
	402
a90917c3	403	static struct lttng_transport lttng_relay_transport = {
881833e3 MD	404	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	405	.owner = THIS_MODULE,
	406	.ops = {
	407	.channel_create = _channel_create,
a90917c3 MD	408	.channel_destroy = lttng_channel_destroy,
a90917c3 MD	409	.buffer_read_open = lttng_buffer_read_open,
f71ecafa	410	.buffer_has_read_closed_stream =
a90917c3 MD	411	lttng_buffer_has_read_closed_stream,
	412	.buffer_read_close = lttng_buffer_read_close,
	413	.event_reserve = lttng_event_reserve,
	414	.event_commit = lttng_event_commit,
	415	.event_write_from_user = lttng_event_write_from_user,
	416	.event_memset = lttng_event_memset,
	417	.event_write = lttng_event_write,
16f78f3a	418	.event_strcpy = lttng_event_strcpy,
a90917c3 MD	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,
67a80835 MD	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,
5b3cf4f9	431	.sequence_number = client_sequence_number,
5594698f	432	.instance_id = client_instance_id,
881833e3 MD	433	},
	434	};
	435
a90917c3	436	static int __init lttng_ring_buffer_client_init(void)
881833e3 MD	437	{
	438	/*
	439	* This vmalloc sync all also takes care of the lib ring buffer
	440	* vmalloc'd module pages when it is built as a module into LTTng.
	441	*/
	442	wrapper_vmalloc_sync_all();
a90917c3	443	lttng_transport_register(&lttng_relay_transport);
881833e3 MD	444	return 0;
	445	}
	446
a90917c3	447	module_init(lttng_ring_buffer_client_init);
881833e3	448
a90917c3	449	static void __exit lttng_ring_buffer_client_exit(void)
881833e3	450	{
a90917c3	451	lttng_transport_unregister(&lttng_relay_transport);
881833e3 MD	452	}
881833e3 MD	453
a90917c3	454	module_exit(lttng_ring_buffer_client_exit);
881833e3 MD	455
	456	MODULE_LICENSE("GPL and additional rights");
	457	MODULE_AUTHOR("Mathieu Desnoyers");
	458	MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
	459	" client");