[lttng-tools.git] / src / common / trace-chunk-registry.h

/*
 * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com>
 *
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 */

#ifndef LTTNG_TRACE_CHUNK_REGISTRY_H
#define LTTNG_TRACE_CHUNK_REGISTRY_H

#include <stddef.h>
#include <stdint.h>
#include <stdbool.h>
#include <common/macros.h>
#include <common/trace-chunk.h>

struct lttng_trace_chunk_registry;

/*
 * Create an lttng_trace_chunk registry.
 *
 * A trace chunk registry maintains an association between a
 * (session_id, chunk_id) tuple and a trace chunk object. The chunk_id can
 * be "unset" in the case of an anonymous trace chunk.
 *
 * Note that a trace chunk registry holds no ownership of its trace
 * chunks. Trace chunks are unpublished when their last reference is released.
 * See the documentation of lttng_trace_chunk.
 *
 * Returns a trace chunk registry on success, NULL on error.
 *
 * Note that a trace chunk registry may only be accessed by an RCU thread.
 */
LTTNG_HIDDEN
struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create(void);

/*
 * Destroy an lttng trace chunk registry. The registry must be emptied
 * (i.e. all references to the trace chunks it contains must be released) before
 * it is destroyed.
 */
LTTNG_HIDDEN
void lttng_trace_chunk_registry_destroy(
		struct lttng_trace_chunk_registry *registry);

/*
 * Publish a trace chunk for a given session id.
 * A reference is acquired on behalf of the caller.
 *
 * The trace chunk that is returned is the published version of the trace
 * chunk. The chunk provided should be discarded on success and it's
 * published version used in its place.
 *
 * See the documentation of lttng_trace_chunk for more information on
 * the usage of the various parameters.
 *
 * Returns an lttng_trace_chunk on success, NULL on error.
 */
LTTNG_HIDDEN
struct lttng_trace_chunk *lttng_trace_chunk_registry_publish_chunk(
		struct lttng_trace_chunk_registry *registry,
		uint64_t session_id, struct lttng_trace_chunk *chunk);

/*
 * Look-up a trace chunk by session_id and chunk_id.
 * A reference is acquired on behalf of the caller.
 *
 * Returns an lttng_trace_chunk on success, NULL if the chunk does not exist.
 */
LTTNG_HIDDEN
struct lttng_trace_chunk *
lttng_trace_chunk_registry_find_chunk(
		const struct lttng_trace_chunk_registry *registry,
		uint64_t session_id, uint64_t chunk_id);

/*
 * Query the existence of a trace chunk by session_id and chunk_id.
 *
 * Returns 0 on success, a negative value on error.
 */
LTTNG_HIDDEN
int lttng_trace_chunk_registry_chunk_exists(
		const struct lttng_trace_chunk_registry *registry,
		uint64_t session_id, uint64_t chunk_id, bool *chunk_exists);

/*
 * Look-up an anonymous trace chunk by session_id.
 * A reference is acquired on behalf of the caller.
 *
 * Returns an lttng_trace_chunk on success, NULL if the chunk does not exist.
 */
LTTNG_HIDDEN
struct lttng_trace_chunk *
lttng_trace_chunk_registry_find_anonymous_chunk(
		const struct lttng_trace_chunk_registry *registry,
		uint64_t session_id);

LTTNG_HIDDEN
unsigned int lttng_trace_chunk_registry_put_each_chunk(
		const struct lttng_trace_chunk_registry *registry);

#endif /* LTTNG_TRACE_CHUNK_REGISTRY_H */
Commit	Line	Data
2c5ff4e4	1	/*
ab5be9fa	2	* Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com>
2c5ff4e4	3	*
ab5be9fa	4	* SPDX-License-Identifier: LGPL-2.1-only
2c5ff4e4	5	*
2c5ff4e4 JG	6	*/
	7
	8	#ifndef LTTNG_TRACE_CHUNK_REGISTRY_H
	9	#define LTTNG_TRACE_CHUNK_REGISTRY_H
	10
	11	#include <stddef.h>
	12	#include <stdint.h>
	13	#include <stdbool.h>
	14	#include <common/macros.h>
	15	#include <common/trace-chunk.h>
	16
	17	struct lttng_trace_chunk_registry;
	18
	19	/*
	20	* Create an lttng_trace_chunk registry.
	21	*
	22	* A trace chunk registry maintains an association between a
	23	* (session_id, chunk_id) tuple and a trace chunk object. The chunk_id can
	24	* be "unset" in the case of an anonymous trace chunk.
	25	*
	26	* Note that a trace chunk registry holds no ownership of its trace
	27	* chunks. Trace chunks are unpublished when their last reference is released.
	28	* See the documentation of lttng_trace_chunk.
	29	*
	30	* Returns a trace chunk registry on success, NULL on error.
	31	*
	32	* Note that a trace chunk registry may only be accessed by an RCU thread.
	33	*/
	34	LTTNG_HIDDEN
	35	struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create(void);
	36
	37	/*
	38	* Destroy an lttng trace chunk registry. The registry must be emptied
	39	* (i.e. all references to the trace chunks it contains must be released) before
	40	* it is destroyed.
	41	*/
	42	LTTNG_HIDDEN
	43	void lttng_trace_chunk_registry_destroy(
	44	struct lttng_trace_chunk_registry *registry);
	45
	46	/*
	47	* Publish a trace chunk for a given session id.
	48	* A reference is acquired on behalf of the caller.
	49	*
	50	* The trace chunk that is returned is the published version of the trace
	51	* chunk. The chunk provided should be discarded on success and it's
	52	* published version used in its place.
	53	*
	54	* See the documentation of lttng_trace_chunk for more information on
	55	* the usage of the various parameters.
	56	*
	57	* Returns an lttng_trace_chunk on success, NULL on error.
	58	*/
	59	LTTNG_HIDDEN
	60	struct lttng_trace_chunk *lttng_trace_chunk_registry_publish_chunk(
	61	struct lttng_trace_chunk_registry *registry,
	62	uint64_t session_id, struct lttng_trace_chunk *chunk);
	63
	64	/*
	65	* Look-up a trace chunk by session_id and chunk_id.
	66	* A reference is acquired on behalf of the caller.
	67	*
	68	* Returns an lttng_trace_chunk on success, NULL if the chunk does not exist.
	69	*/
70	LTTNG_HIDDEN
71	struct lttng_trace_chunk *
72	lttng_trace_chunk_registry_find_chunk(
73	const struct lttng_trace_chunk_registry *registry,
74	uint64_t session_id, uint64_t chunk_id);
75
6b584c2e JG	76	/*
	77	* Query the existence of a trace chunk by session_id and chunk_id.
	78	*
	79	* Returns 0 on success, a negative value on error.
	80	*/
	81	LTTNG_HIDDEN
	82	int lttng_trace_chunk_registry_chunk_exists(
	83	const struct lttng_trace_chunk_registry *registry,
	84	uint64_t session_id, uint64_t chunk_id, bool *chunk_exists);
	85
2c5ff4e4 JG	86	/*
	87	* Look-up an anonymous trace chunk by session_id.
	88	* A reference is acquired on behalf of the caller.
	89	*
	90	* Returns an lttng_trace_chunk on success, NULL if the chunk does not exist.
	91	*/
	92	LTTNG_HIDDEN
	93	struct lttng_trace_chunk *
	94	lttng_trace_chunk_registry_find_anonymous_chunk(
	95	const struct lttng_trace_chunk_registry *registry,
	96	uint64_t session_id);
	97
e10aec8f MD	98	LTTNG_HIDDEN
e10aec8f MD	99	unsigned int lttng_trace_chunk_registry_put_each_chunk(
8ced4811	100	const struct lttng_trace_chunk_registry *registry);
e10aec8f	101
2c5ff4e4	102	#endif /* LTTNG_TRACE_CHUNK_REGISTRY_H */