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

/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
 *
 * lttng-ring-buffer-event-notifier-client.h
 *
 * LTTng lib ring buffer event notifier client template.
 *
 * Copyright (C) 2010-2020 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

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

static struct lttng_transport lttng_relay_transport;

struct event_notifier_packet_header {
	uint8_t  header_end[0];
};

struct event_notifier_record_header {
	uint32_t payload_len;		/* in bytes */
	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,
				 void *client_ctx)
{
	size_t orig_offset = offset;
	size_t padding;

	padding = lib_ring_buffer_align(offset, lttng_alignof(uint32_t));
	offset += padding;

	offset += sizeof(uint32_t);

	*pre_header_padding = padding;

	return offset - orig_offset;
}

#include <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,
				 void *client_ctx)
{
	return record_header_size(config, chan, offset,
				  pre_header_padding, ctx, client_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 event_notifier_packet_header, header_end);
}

static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
				unsigned int subbuf_idx)
{
}

/*
 * 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)
{
}

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 void client_record_get(const struct lib_ring_buffer_config *config,
	struct channel *chan, struct lib_ring_buffer *buf,
	size_t offset, size_t *header_len,
	size_t *payload_len, u64 *timestamp)
{
	struct event_notifier_record_header header;
	int ret;

	ret = lib_ring_buffer_read(&buf->backend, offset, &header,
			offsetof(struct event_notifier_record_header, header_end));
	CHAN_WARN_ON(chan, ret != offsetof(struct event_notifier_record_header, header_end));
	*header_len = offsetof(struct event_notifier_record_header, header_end);
	*payload_len = header.payload_len;
	*timestamp = 0;
}

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,
	.cb.record_get = client_record_get,

	.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_NO_IPI_BARRIER,
	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
};

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,
				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_event_notifier_group *event_notifier_group = priv;
	struct channel *chan;

	chan = channel_create(&client_config, name,
			      event_notifier_group, 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 event_notifier 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
void lttng_write_event_notifier_header(const struct lib_ring_buffer_config *config,
			    struct lib_ring_buffer_ctx *ctx)
{
	uint32_t data_size;

	WARN_ON_ONCE(ctx->data_size > U32_MAX);

	data_size = (uint32_t) ctx->data_size;

	lib_ring_buffer_write(config, ctx, &data_size, sizeof(data_size));

	lib_ring_buffer_align_ctx(ctx, ctx->largest_align);
}

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, NULL);
	if (ret)
		return ret;
	lib_ring_buffer_backend_get_pages(&client_config, ctx,
			&ctx->backend_pages);

	lttng_write_event_notifier_header(&client_config, ctx);
	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 event_notifier_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_event_notifier_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_event_notifier_client_init);

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

module_exit(lttng_ring_buffer_event_notifier_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
250c663f MD	1	/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
	2	*
	3	* lttng-ring-buffer-event-notifier-client.h
	4	*
	5	* LTTng lib ring buffer event notifier client template.
	6	*
	7	* Copyright (C) 2010-2020 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*/
	9
99d223ad	10	#include <linux/limits.h>
250c663f MD	11	#include <linux/module.h>
	12	#include <linux/types.h>
	13	#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
99d223ad	14	#include <lttng/abi.h>
250c663f MD	15	#include <lttng/events.h>
250c663f MD	16	#include <lttng/tracer.h>
236233f7	17	#include <wrapper/limits.h>
250c663f MD	18
	19	static struct lttng_transport lttng_relay_transport;
	20
	21	struct event_notifier_packet_header {
	22	uint8_t header_end[0];
	23	};
	24
	25	struct event_notifier_record_header {
99d223ad	26	uint32_t payload_len; /* in bytes */
250c663f MD	27	uint8_t header_end[0]; /* End of header */
	28	};
	29
	30	static const struct lib_ring_buffer_config client_config;
	31
	32	static inline
	33	u64 lib_ring_buffer_clock_read(struct channel *chan)
	34	{
	35	return 0;
	36	}
	37
	38	static inline
	39	size_t record_header_size(const struct lib_ring_buffer_config *config,
	40	struct channel *chan, size_t offset,
	41	size_t *pre_header_padding,
	42	struct lib_ring_buffer_ctx *ctx,
	43	void *client_ctx)
	44	{
99d223ad FD	45	size_t orig_offset = offset;
	46	size_t padding;
	47
	48	padding = lib_ring_buffer_align(offset, lttng_alignof(uint32_t));
	49	offset += padding;
	50
	51	offset += sizeof(uint32_t);
	52
	53	*pre_header_padding = padding;
	54
	55	return offset - orig_offset;
250c663f MD	56	}
	57
	58	#include <ringbuffer/api.h>
	59
	60	static u64 client_ring_buffer_clock_read(struct channel *chan)
	61	{
	62	return 0;
	63	}
	64
	65	static
	66	size_t client_record_header_size(const struct lib_ring_buffer_config *config,
	67	struct channel *chan, size_t offset,
	68	size_t *pre_header_padding,
	69	struct lib_ring_buffer_ctx *ctx,
	70	void *client_ctx)
	71	{
99d223ad FD	72	return record_header_size(config, chan, offset,
99d223ad FD	73	pre_header_padding, ctx, client_ctx);
250c663f MD	74	}
	75
	76	/**
	77	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	78	*
	79	* Return header size without padding after the structure. Don't use packed
	80	* structure because gcc generates inefficient code on some architectures
	81	* (powerpc, mips..)
	82	*/
	83	static size_t client_packet_header_size(void)
	84	{
	85	return offsetof(struct event_notifier_packet_header, header_end);
	86	}
	87
	88	static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
	89	unsigned int subbuf_idx)
	90	{
	91	}
	92
	93	/*
	94	* offset is assumed to never be 0 here : never deliver a completely empty
	95	* subbuffer. data_size is between 1 and subbuf_size.
	96	*/
	97	static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
	98	unsigned int subbuf_idx, unsigned long data_size)
	99	{
	100	}
	101
	102	static int client_buffer_create(struct lib_ring_buffer buf, void priv,
	103	int cpu, const char *name)
	104	{
	105	return 0;
	106	}
	107
	108	static void client_buffer_finalize(struct lib_ring_buffer buf, void priv, int cpu)
	109	{
	110	}
	111
	112	static int client_timestamp_begin(const struct lib_ring_buffer_config *config,
	113	struct lib_ring_buffer buf, uint64_t timestamp_begin)
	114	{
	115	return -ENOSYS;
	116	}
	117
	118	static int client_timestamp_end(const struct lib_ring_buffer_config *config,
	119	struct lib_ring_buffer *bufb,
	120	uint64_t *timestamp_end)
	121	{
	122	return -ENOSYS;
	123	}
	124
	125	static int client_events_discarded(const struct lib_ring_buffer_config *config,
	126	struct lib_ring_buffer *bufb,
	127	uint64_t *events_discarded)
	128	{
	129	return -ENOSYS;
	130	}
	131
	132	static int client_current_timestamp(const struct lib_ring_buffer_config *config,
	133	struct lib_ring_buffer *bufb,
	134	uint64_t *ts)
	135	{
	136	return -ENOSYS;
	137	}
138
139	static int client_content_size(const struct lib_ring_buffer_config *config,
140	struct lib_ring_buffer *bufb,
141	uint64_t *content_size)
142	{
143	return -ENOSYS;
144	}
145
146	static int client_packet_size(const struct lib_ring_buffer_config *config,
147	struct lib_ring_buffer *bufb,
148	uint64_t *packet_size)
149	{
150	return -ENOSYS;
151	}
152
153	static int client_stream_id(const struct lib_ring_buffer_config *config,
154	struct lib_ring_buffer *bufb,
155	uint64_t *stream_id)
156	{
157	return -ENOSYS;
158	}
159
160	static int client_sequence_number(const struct lib_ring_buffer_config *config,
161	struct lib_ring_buffer *bufb,
162	uint64_t *seq)
163	{
164	return -ENOSYS;
165	}
166
167	static
168	int client_instance_id(const struct lib_ring_buffer_config *config,
169	struct lib_ring_buffer *bufb,
170	uint64_t *id)
171	{
172	return -ENOSYS;
173	}
174
175	static void client_record_get(const struct lib_ring_buffer_config *config,
176	struct channel chan, struct lib_ring_buffer buf,
177	size_t offset, size_t *header_len,
178	size_t payload_len, u64 timestamp)
179	{
180	struct event_notifier_record_header header;
181	int ret;
182
183	ret = lib_ring_buffer_read(&buf->backend, offset, &header,
184	offsetof(struct event_notifier_record_header, header_end));
185	CHAN_WARN_ON(chan, ret != offsetof(struct event_notifier_record_header, header_end));
186	*header_len = offsetof(struct event_notifier_record_header, header_end);
99d223ad	187	*payload_len = header.payload_len;
250c663f MD	188	*timestamp = 0;
	189	}
	190
	191	static const struct lib_ring_buffer_config client_config = {
	192	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	193	.cb.record_header_size = client_record_header_size,
	194	.cb.subbuffer_header_size = client_packet_header_size,
	195	.cb.buffer_begin = client_buffer_begin,
	196	.cb.buffer_end = client_buffer_end,
	197	.cb.buffer_create = client_buffer_create,
	198	.cb.buffer_finalize = client_buffer_finalize,
	199	.cb.record_get = client_record_get,
	200
	201	.tsc_bits = 0,
	202	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	203	.sync = RING_BUFFER_SYNC_GLOBAL,
	204	.mode = RING_BUFFER_MODE_TEMPLATE,
	205	.backend = RING_BUFFER_PAGE,
	206	.output = RING_BUFFER_OUTPUT_TEMPLATE,
	207	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	208	.ipi = RING_BUFFER_NO_IPI_BARRIER,
	209	.wakeup = RING_BUFFER_WAKEUP_BY_WRITER,
	210	};
	211
	212	static
	213	void release_priv_ops(void *priv_ops)
	214	{
	215	module_put(THIS_MODULE);
	216	}
	217
	218	static
	219	void lttng_channel_destroy(struct channel *chan)
	220	{
	221	channel_destroy(chan);
	222	}
	223
	224	static
	225	struct channel _channel_create(const char name,
	226	void priv, void buf_addr,
	227	size_t subbuf_size, size_t num_subbuf,
	228	unsigned int switch_timer_interval,
	229	unsigned int read_timer_interval)
	230	{
	231	struct lttng_event_notifier_group *event_notifier_group = priv;
	232	struct channel *chan;
	233
	234	chan = channel_create(&client_config, name,
	235	event_notifier_group, buf_addr,
	236	subbuf_size, num_subbuf, switch_timer_interval,
	237	read_timer_interval);
	238	if (chan) {
	239	/*
	240	* Ensure this module is not unloaded before we finish
	241	* using lttng_relay_transport.ops.
	242	*/
	243	if (!try_module_get(THIS_MODULE)) {
	244	printk(KERN_WARNING "LTTng: Can't lock event_notifier transport module.\n");
	245	goto error;
	246	}
	247	chan->backend.priv_ops = &lttng_relay_transport.ops;
	248	chan->backend.release_priv_ops = release_priv_ops;
	249	}
	250	return chan;
	251
252	error:
253	lttng_channel_destroy(chan);
254	return NULL;
255	}
256
257	static
258	struct lib_ring_buffer lttng_buffer_read_open(struct channel chan)
259	{
260	struct lib_ring_buffer *buf;
261
262	buf = channel_get_ring_buffer(&client_config, chan, 0);
263	if (!lib_ring_buffer_open_read(buf))
264	return buf;
265	return NULL;
266	}
267
268	static
269	int lttng_buffer_has_read_closed_stream(struct channel *chan)
270	{
271	struct lib_ring_buffer *buf;
272	int cpu;
273
274	for_each_channel_cpu(cpu, chan) {
275	buf = channel_get_ring_buffer(&client_config, chan, cpu);
276	if (!atomic_long_read(&buf->active_readers))
277	return 1;
278	}
279	return 0;
280	}
281
282	static
283	void lttng_buffer_read_close(struct lib_ring_buffer *buf)
284	{
285	lib_ring_buffer_release_read(buf);
286	}
287
99d223ad FD	288	static
	289	void lttng_write_event_notifier_header(const struct lib_ring_buffer_config *config,
	290	struct lib_ring_buffer_ctx *ctx)
	291	{
	292	uint32_t data_size;
	293
	294	WARN_ON_ONCE(ctx->data_size > U32_MAX);
	295
	296	data_size = (uint32_t) ctx->data_size;
	297
	298	lib_ring_buffer_write(config, ctx, &data_size, sizeof(data_size));
	299
	300	lib_ring_buffer_align_ctx(ctx, ctx->largest_align);
	301	}
	302
250c663f MD	303	static
	304	int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id)
	305	{
	306	int ret;
	307
	308	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
	309	if (ret)
	310	return ret;
	311	lib_ring_buffer_backend_get_pages(&client_config, ctx,
	312	&ctx->backend_pages);
99d223ad FD	313
99d223ad FD	314	lttng_write_event_notifier_header(&client_config, ctx);
250c663f MD	315	return 0;
	316	}
	317
	318	static
	319	void lttng_event_commit(struct lib_ring_buffer_ctx *ctx)
	320	{
	321	lib_ring_buffer_commit(&client_config, ctx);
	322	}
	323
	324	static
	325	void lttng_event_write(struct lib_ring_buffer_ctx ctx, const void src,
	326	size_t len)
	327	{
	328	lib_ring_buffer_write(&client_config, ctx, src, len);
	329	}
	330
	331	static
	332	void lttng_event_write_from_user(struct lib_ring_buffer_ctx *ctx,
	333	const void __user *src, size_t len)
	334	{
	335	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
	336	}
	337
	338	static
	339	void lttng_event_memset(struct lib_ring_buffer_ctx *ctx,
	340	int c, size_t len)
	341	{
	342	lib_ring_buffer_memset(&client_config, ctx, c, len);
	343	}
	344
	345	static
	346	void lttng_event_strcpy(struct lib_ring_buffer_ctx ctx, const char src,
	347	size_t len)
	348	{
	349	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
	350	}
	351
	352	static
	353	size_t lttng_packet_avail_size(struct channel *chan)
	354	{
	355	unsigned long o_begin;
	356	struct lib_ring_buffer *buf;
	357
	358	buf = chan->backend.buf; /* Only for global buffer ! */
	359	o_begin = v_read(&client_config, &buf->offset);
	360	if (subbuf_offset(o_begin, chan) != 0) {
	361	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	362	} else {
	363	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	364	- sizeof(struct event_notifier_packet_header);
	365	}
	366	}
	367
	368	static
	369	wait_queue_head_t lttng_get_writer_buf_wait_queue(struct channel chan, int cpu)
	370	{
	371	struct lib_ring_buffer *buf = channel_get_ring_buffer(&client_config,
	372	chan, cpu);
	373	return &buf->write_wait;
	374	}
	375
	376	static
	377	wait_queue_head_t lttng_get_hp_wait_queue(struct channel chan)
	378	{
379	return &chan->hp_wait;
380	}
381
382	static
383	int lttng_is_finalized(struct channel *chan)
384	{
385	return lib_ring_buffer_channel_is_finalized(chan);
386	}
387
388	static
389	int lttng_is_disabled(struct channel *chan)
390	{
391	return lib_ring_buffer_channel_is_disabled(chan);
392	}
393
394	static struct lttng_transport lttng_relay_transport = {
395	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
396	.owner = THIS_MODULE,
397	.ops = {
398	.channel_create = _channel_create,
399	.channel_destroy = lttng_channel_destroy,
400	.buffer_read_open = lttng_buffer_read_open,
401	.buffer_has_read_closed_stream =
402	lttng_buffer_has_read_closed_stream,
403	.buffer_read_close = lttng_buffer_read_close,
404	.event_reserve = lttng_event_reserve,
405	.event_commit = lttng_event_commit,
406	.event_write_from_user = lttng_event_write_from_user,
407	.event_memset = lttng_event_memset,
408	.event_write = lttng_event_write,
409	.event_strcpy = lttng_event_strcpy,
410	.packet_avail_size = lttng_packet_avail_size,
411	.get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue,
412	.get_hp_wait_queue = lttng_get_hp_wait_queue,
413	.is_finalized = lttng_is_finalized,
414	.is_disabled = lttng_is_disabled,
415	.timestamp_begin = client_timestamp_begin,
416	.timestamp_end = client_timestamp_end,
417	.events_discarded = client_events_discarded,
418	.content_size = client_content_size,
419	.packet_size = client_packet_size,
420	.stream_id = client_stream_id,
421	.current_timestamp = client_current_timestamp,
422	.sequence_number = client_sequence_number,
423	.instance_id = client_instance_id,
424	},
425	};
426
427	static int __init lttng_ring_buffer_event_notifier_client_init(void)
428	{
429	/*
430	* This vmalloc sync all also takes care of the lib ring buffer
431	* vmalloc'd module pages when it is built as a module into LTTng.
432	*/
433	wrapper_vmalloc_sync_mappings();
434	lttng_transport_register(&lttng_relay_transport);
435	return 0;
436	}
437
438	module_init(lttng_ring_buffer_event_notifier_client_init);
439
440	static void __exit lttng_ring_buffer_event_notifier_client_exit(void)
441	{
442	lttng_transport_unregister(&lttng_relay_transport);
443	}
444
445	module_exit(lttng_ring_buffer_event_notifier_client_exit);
446
447	MODULE_LICENSE("GPL and additional rights");
448	MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
449	MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
450	" client");
451	MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
452	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
453	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
454	LTTNG_MODULES_EXTRAVERSION);