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

#ifndef _SESSION_H
#define _SESSION_H

/*
 * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
 *                      David Goulet <dgoulet@efficios.com>
 *               2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License, version 2 only, as
 * published by the Free Software Foundation.
 *
 * This program 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 General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#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>

/*
 * 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;
	char session_name[LTTNG_NAME_MAX];
	char hostname[LTTNG_HOST_NAME_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;

	/* 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 rcu_head rcu_node;	/* For call_rcu teardown. */
};

struct relay_session *session_create(const char *session_name,
		const char *hostname, uint32_t live_timer,
		bool snapshot, uint32_t major, uint32_t minor);
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	* David Goulet <dgoulet@efficios.com>
	7	* 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	*
	9	* This program is free software; you can redistribute it and/or modify it
	10	* under the terms of the GNU General Public License, version 2 only, as
	11	* published by the Free Software Foundation.
	12	*
	13	* This program is distributed in the hope that it will be useful, but WITHOUT
	14	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	16	* more details.
	17	*
	18	* You should have received a copy of the GNU General Public License along with
	19	* this program; if not, write to the Free Software Foundation, Inc., 51
	20	* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	21	*/
	22
	23	#include <limits.h>
	24	#include <inttypes.h>
	25	#include <pthread.h>
	26	#include <urcu/list.h>
	27	#include <urcu/ref.h>
	28
	29	#include <lttng/constant.h>
	30	#include <common/hashtable/hashtable.h>
	31
	32	/*
	33	* Represents a session for the relay point of view
	34	*/
	35	struct relay_session {
	36	/*
	37	* This session id is generated by the relay daemon to guarantee
	38	* its uniqueness even when serving multiple session daemons.
	39	* It is used to match a set of streams to their session.
	40	*/
	41	uint64_t id;
	42	char session_name[LTTNG_NAME_MAX];
	43	char hostname[LTTNG_HOST_NAME_MAX];
	44	uint32_t live_timer;
	45
	46	/* Session in snapshot mode. */
	47	bool snapshot;
	48
	49	/*
	50	* Session has no back reference to its connection because it
	51	* has a life-time that can be longer than the consumer connection's
	52	* life-time; a reference can still be held by the viewer
	53	* connection through the viewer streams.
	54	*/
	55
	56	struct urcu_ref ref;
	57
	58	pthread_mutex_t lock;
	59
	60	/* major/minor version used for this session. */
	61	uint32_t major;
	62	uint32_t minor;
	63
	64	bool viewer_attached;
	65	/* Tell if the session connection has been closed on the streaming side. */
	66	bool connection_closed;
	67
	68	/*
	69	* Tell if the session is currently living in a exiting relayd and
	70	* should be cleaned forcefully without waiting for pending data or
	71	* pending ctrl data.
	72	*/
	73	bool aborted;
	74
	75	/* Contains ctf_trace object of that session indexed by path name. */
	76	struct lttng_ht *ctf_traces_ht;
	77
	78	/*
	79	* This contains streams that are received on that connection.
	80	* It's used to store them until we get the streams sent
	81	* command. When this is received, we remove those streams from
	82	* the list and publish them.
	83	*
	84	* Updates are protected by the recv_list_lock.
	85	* Traversals are protected by RCU.
	86	* recv_list_lock also protects stream_count.
	87	*/
	88	struct cds_list_head recv_list; /* RCU list. */
	89	uint32_t stream_count;
	90	pthread_mutex_t recv_list_lock;
	91
	92	/*
	93	* Flag checked and exchanged with uatomic_cmpxchg to tell the
	94	* viewer-side if new streams got added since the last check.
	95	*/
	96	unsigned long new_streams;
	97
	98	/*
	99	* Node in the global session hash table.
	100	*/
	101	struct lttng_ht_node_u64 session_n;
	102	/*
	103	* Member of the session list in struct relay_viewer_session.
	104	* Updates are protected by the relay_viewer_session
	105	* session_list_lock. Traversals are protected by RCU.
	106	*/
	107	struct cds_list_head viewer_session_node;
	108	struct rcu_head rcu_node; /* For call_rcu teardown. */
	109	};
	110
	111	struct relay_session session_create(const char session_name,
	112	const char *hostname, uint32_t live_timer,
	113	bool snapshot, uint32_t major, uint32_t minor);
	114	struct relay_session *session_get_by_id(uint64_t id);
	115	bool session_get(struct relay_session *session);
	116	void session_put(struct relay_session *session);
	117
	118	int session_close(struct relay_session *session);
	119	int session_abort(struct relay_session *session);
	120
	121	void print_sessions(void);
	122
	123	#endif /* _SESSION_H */