[lttng-tools.git] / src / bin / lttng-relayd / session.h

#ifndef _SESSION_H
#define _SESSION_H

/*
 * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
 * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
 * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#include <limits.h>
#include <inttypes.h>
#include <pthread.h>
#include <urcu/list.h>
#include <urcu/ref.h>

#include <lttng/constant.h>
#include <common/hashtable/hashtable.h>
#include <common/uuid.h>
#include <common/trace-chunk.h>
#include <common/optional.h>

/*
 * Represents a session for the relay point of view
 */
struct relay_session {
	/*
	 * This session id is generated by the relay daemon to guarantee
	 * its uniqueness even when serving multiple session daemons.
	 * It is used to match a set of streams to their session.
	 */
	uint64_t id;
	/*
	 * ID of the session in the session daemon's domain.
	 * This information is only provided by 2.11+ peers.
	 */
	LTTNG_OPTIONAL(uint64_t) id_sessiond;
	/*
	 * Only provided by 2.11+ peers. However, the UUID is set to 'nil' in
	 * the other cases.
	 */
	lttng_uuid sessiond_uuid;
	/*
	 * Contains the creation time on the session daemon's end for 2.11+
	 * peers. Otherwise, this contains the session creation time on the
	 * relay daemon's end.
	 */
	LTTNG_OPTIONAL(time_t) creation_time;
	/* Must _not_ be empty for 2.4+ peers. */
	char session_name[LTTNG_NAME_MAX];
	char hostname[LTTNG_HOST_NAME_MAX];
	char base_path[LTTNG_PATH_MAX];
	/*
	 * Session output path relative to relayd's output path.
	 * Will be empty when interacting with peers < 2.11 since their
	 * streams' path are expressed relative to the relay daemon's
	 * output path.
	 */
	char output_path[LTTNG_PATH_MAX];
	uint32_t live_timer;

	/* Session in snapshot mode. */
	bool snapshot;

	/*
	 * Session has no back reference to its connection because it
	 * has a life-time that can be longer than the consumer connection's
	 * life-time; a reference can still be held by the viewer
	 * connection through the viewer streams.
	 */

	struct urcu_ref ref;

	pthread_mutex_t lock;

	/* major/minor version used for this session. */
	uint32_t major;
	uint32_t minor;

	bool viewer_attached;
	/* Tell if the session connection has been closed on the streaming side. */
	bool connection_closed;

	/*
	 * Tell if the session is currently living in a exiting relayd and
	 * should be cleaned forcefully without waiting for pending data or
	 * pending ctrl data.
	 */
	bool aborted;

	bool session_name_contains_creation_time;
	/* Whether session has performed an explicit rotation. */
	bool has_rotated;

	/* Contains ctf_trace object of that session indexed by path name. */
	struct lttng_ht *ctf_traces_ht;

	/*
	 * This contains streams that are received on that connection.
	 * It's used to store them until we get the streams sent
	 * command. When this is received, we remove those streams from
	 * the list and publish them.
	 *
	 * Updates are protected by the recv_list_lock.
	 * Traversals are protected by RCU.
	 * recv_list_lock also protects stream_count.
	 */
	struct cds_list_head recv_list;	/* RCU list. */
	uint32_t stream_count;
	pthread_mutex_t recv_list_lock;

	/*
	 * Flag checked and exchanged with uatomic_cmpxchg to tell the
	 * viewer-side if new streams got added since the last check.
	 */
	unsigned long new_streams;

	/*
	 * Node in the global session hash table.
	 */
	struct lttng_ht_node_u64 session_n;
	/*
	 * Member of the session list in struct relay_viewer_session.
	 * Updates are protected by the relay_viewer_session
	 * session_list_lock. Traversals are protected by RCU.
	 */
	struct cds_list_head viewer_session_node;
	struct lttng_trace_chunk *current_trace_chunk;
	struct lttng_trace_chunk *pending_closure_trace_chunk;
	/*
	 * Prevent live viewers from taking of copy of the chunk
	 * while new chunk has a temporary directory name.
	 */
	bool ongoing_rotation;
	struct lttng_directory_handle *output_directory;
	struct rcu_head rcu_node;	/* For call_rcu teardown. */
};

struct relay_session *session_create(const char *session_name,
		const char *hostname, const char *base_path,
		uint32_t live_timer,
		bool snapshot,
		const lttng_uuid sessiond_uuid,
		const uint64_t *id_sessiond,
		const uint64_t *current_chunk_id,
		const time_t *creation_time,
		uint32_t major,
		uint32_t minor,
		bool session_name_contains_creation_timestamp);
struct relay_session *session_get_by_id(uint64_t id);
bool session_get(struct relay_session *session);
void session_put(struct relay_session *session);

int session_close(struct relay_session *session);
int session_abort(struct relay_session *session);

void print_sessions(void);

#endif /* _SESSION_H */
Commit	Line	Data
	1	#ifndef _SESSION_H
	2	#define _SESSION_H
	3
	4	/*
	5	* Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
	6	* Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
	7	* Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* SPDX-License-Identifier: GPL-2.0-only
	10	*
	11	*/
	12
	13	#include <limits.h>
	14	#include <inttypes.h>
	15	#include <pthread.h>
	16	#include <urcu/list.h>
	17	#include <urcu/ref.h>
	18
	19	#include <lttng/constant.h>
	20	#include <common/hashtable/hashtable.h>
	21	#include <common/uuid.h>
	22	#include <common/trace-chunk.h>
	23	#include <common/optional.h>
	24
	25	/*
	26	* Represents a session for the relay point of view
	27	*/
	28	struct relay_session {
	29	/*
	30	* This session id is generated by the relay daemon to guarantee
	31	* its uniqueness even when serving multiple session daemons.
	32	* It is used to match a set of streams to their session.
	33	*/
	34	uint64_t id;
	35	/*
	36	* ID of the session in the session daemon's domain.
	37	* This information is only provided by 2.11+ peers.
	38	*/
	39	LTTNG_OPTIONAL(uint64_t) id_sessiond;
	40	/*
	41	* Only provided by 2.11+ peers. However, the UUID is set to 'nil' in
	42	* the other cases.
	43	*/
	44	lttng_uuid sessiond_uuid;
	45	/*
	46	* Contains the creation time on the session daemon's end for 2.11+
	47	* peers. Otherwise, this contains the session creation time on the
	48	* relay daemon's end.
	49	*/
	50	LTTNG_OPTIONAL(time_t) creation_time;
	51	/* Must _not_ be empty for 2.4+ peers. */
	52	char session_name[LTTNG_NAME_MAX];
	53	char hostname[LTTNG_HOST_NAME_MAX];
	54	char base_path[LTTNG_PATH_MAX];
	55	/*
	56	* Session output path relative to relayd's output path.
	57	* Will be empty when interacting with peers < 2.11 since their
	58	* streams' path are expressed relative to the relay daemon's
	59	* output path.
	60	*/
	61	char output_path[LTTNG_PATH_MAX];
	62	uint32_t live_timer;
	63
	64	/* Session in snapshot mode. */
	65	bool snapshot;
	66
	67	/*
	68	* Session has no back reference to its connection because it
	69	* has a life-time that can be longer than the consumer connection's
	70	* life-time; a reference can still be held by the viewer
	71	* connection through the viewer streams.
	72	*/
	73
	74	struct urcu_ref ref;
	75
	76	pthread_mutex_t lock;
	77
	78	/* major/minor version used for this session. */
	79	uint32_t major;
	80	uint32_t minor;
	81
	82	bool viewer_attached;
	83	/* Tell if the session connection has been closed on the streaming side. */
	84	bool connection_closed;
	85
	86	/*
	87	* Tell if the session is currently living in a exiting relayd and
	88	* should be cleaned forcefully without waiting for pending data or
	89	* pending ctrl data.
	90	*/
	91	bool aborted;
	92
	93	bool session_name_contains_creation_time;
	94	/* Whether session has performed an explicit rotation. */
	95	bool has_rotated;
	96
	97	/* Contains ctf_trace object of that session indexed by path name. */
	98	struct lttng_ht *ctf_traces_ht;
	99
	100	/*
	101	* This contains streams that are received on that connection.
	102	* It's used to store them until we get the streams sent
	103	* command. When this is received, we remove those streams from
	104	* the list and publish them.
	105	*
	106	* Updates are protected by the recv_list_lock.
	107	* Traversals are protected by RCU.
	108	* recv_list_lock also protects stream_count.
	109	*/
	110	struct cds_list_head recv_list; /* RCU list. */
	111	uint32_t stream_count;
	112	pthread_mutex_t recv_list_lock;
	113
	114	/*
	115	* Flag checked and exchanged with uatomic_cmpxchg to tell the
	116	* viewer-side if new streams got added since the last check.
	117	*/
	118	unsigned long new_streams;
	119
	120	/*
	121	* Node in the global session hash table.
	122	*/
	123	struct lttng_ht_node_u64 session_n;
	124	/*
	125	* Member of the session list in struct relay_viewer_session.
	126	* Updates are protected by the relay_viewer_session
	127	* session_list_lock. Traversals are protected by RCU.
	128	*/
	129	struct cds_list_head viewer_session_node;
	130	struct lttng_trace_chunk *current_trace_chunk;
	131	struct lttng_trace_chunk *pending_closure_trace_chunk;
	132	/*
	133	* Prevent live viewers from taking of copy of the chunk
	134	* while new chunk has a temporary directory name.
	135	*/
	136	bool ongoing_rotation;
	137	struct lttng_directory_handle *output_directory;
	138	struct rcu_head rcu_node; /* For call_rcu teardown. */
	139	};
	140
	141	struct relay_session session_create(const char session_name,
	142	const char hostname, const char base_path,
	143	uint32_t live_timer,
	144	bool snapshot,
	145	const lttng_uuid sessiond_uuid,
	146	const uint64_t *id_sessiond,
	147	const uint64_t *current_chunk_id,
	148	const time_t *creation_time,
	149	uint32_t major,
	150	uint32_t minor,
	151	bool session_name_contains_creation_timestamp);
	152	struct relay_session *session_get_by_id(uint64_t id);
	153	bool session_get(struct relay_session *session);
	154	void session_put(struct relay_session *session);
	155
	156	int session_close(struct relay_session *session);
	157	int session_abort(struct relay_session *session);
	158
	159	void print_sessions(void);
	160
	161	#endif /* _SESSION_H */