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

/*
 * 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.
 */

#define _LGPL_SOURCE
#include <common/common.h>
#include <common/compat/uuid.h>
#include <urcu/rculist.h>

#include "lttng-relayd.h"
#include "ctf-trace.h"
#include "session.h"
#include "stream.h"
#include "sessiond-trace-chunks.h"

/* Global session id used in the session creation. */
static uint64_t last_relay_session_id;
static pthread_mutex_t last_relay_session_id_lock = PTHREAD_MUTEX_INITIALIZER;

static int session_set_anonymous_chunk(struct relay_session *session)
{
	int ret = 0;
	struct lttng_trace_chunk *chunk = NULL;
	enum lttng_trace_chunk_status status;
	struct lttng_directory_handle output_directory;

	ret = lttng_directory_handle_init(&output_directory, opt_output_path);
	if (ret) {
		goto end;
	}

	chunk = lttng_trace_chunk_create_anonymous();
	if (!chunk) {
		goto end;
	}

	status = lttng_trace_chunk_set_credentials_current_user(chunk);
	if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
		ret = -1;
		goto end;
	}

	status = lttng_trace_chunk_set_as_owner(chunk, &output_directory);
	if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
		ret = -1;
		goto end;
	}
	session->current_trace_chunk = chunk;
	chunk = NULL;
end:
	lttng_trace_chunk_put(chunk);
	lttng_directory_handle_fini(&output_directory);
	return ret;
}

/*
 * Create a new session by assigning a new session ID.
 *
 * Return allocated session or else NULL.
 */
struct relay_session *session_create(const char *session_name,
		const char *hostname, uint32_t live_timer,
		bool snapshot, const lttng_uuid sessiond_uuid,
		uint64_t *id_sessiond, uint64_t *current_chunk_id,
		uint32_t major, uint32_t minor)
{
	int ret;
	struct relay_session *session;

	session = zmalloc(sizeof(*session));
	if (!session) {
		PERROR("Failed to allocate session");
		goto error;
	}
	if (lttng_strncpy(session->session_name, session_name,
			sizeof(session->session_name))) {
	        WARN("Session name exceeds maximal allowed length");
		goto error;
	}
	if (lttng_strncpy(session->hostname, hostname,
			sizeof(session->hostname))) {
		WARN("Hostname exceeds maximal allowed length");
		goto error;
	}
	session->ctf_traces_ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
	if (!session->ctf_traces_ht) {
		goto error;
	}

	pthread_mutex_lock(&last_relay_session_id_lock);
	session->id = ++last_relay_session_id;
	pthread_mutex_unlock(&last_relay_session_id_lock);

	session->major = major;
	session->minor = minor;
	lttng_ht_node_init_u64(&session->session_n, session->id);
	urcu_ref_init(&session->ref);
	CDS_INIT_LIST_HEAD(&session->recv_list);
	pthread_mutex_init(&session->lock, NULL);
	pthread_mutex_init(&session->recv_list_lock, NULL);

	session->live_timer = live_timer;
	session->snapshot = snapshot;
	lttng_uuid_copy(session->sessiond_uuid, sessiond_uuid);

	if (id_sessiond) {
		LTTNG_OPTIONAL_SET(&session->id_sessiond, *id_sessiond);
	}

	ret = sessiond_trace_chunk_registry_session_created(
			sessiond_trace_chunk_registry, sessiond_uuid);
	if (ret) {
		goto error;
	}

	if (id_sessiond && current_chunk_id) {
		session->current_trace_chunk =
				sessiond_trace_chunk_registry_get_chunk(
					sessiond_trace_chunk_registry,
					session->sessiond_uuid,
					session->id_sessiond.value,
					*current_chunk_id);
		if (!session->current_trace_chunk) {
		        char uuid_str[UUID_STR_LEN];

			lttng_uuid_to_str(sessiond_uuid, uuid_str);
			ERR("Could not find trace chunk: sessiond = {%s}, sessiond session id = %" PRIu64 ", trace chunk id = %" PRIu64,
					uuid_str, *id_sessiond,
					*current_chunk_id);
                }
	} else if (!id_sessiond) {
		/*
		 * Pre-2.11 peers will not announce trace chunks. An
		 * anonymous trace chunk which will remain set for the
		 * duration of the session is created.
		 */
		ret = session_set_anonymous_chunk(session);
		if (ret) {
			goto error;
		}
	}

	lttng_ht_add_unique_u64(sessions_ht, &session->session_n);
	return session;

error:
	session_put(session);
	return NULL;
}

/* Should be called with RCU read-side lock held. */
bool session_get(struct relay_session *session)
{
	return urcu_ref_get_unless_zero(&session->ref);
}

/*
 * Lookup a session within the session hash table using the session id
 * as key. A session reference is taken when a session is returned.
 * session_put() must be called on that session.
 *
 * Return session or NULL if not found.
 */
struct relay_session *session_get_by_id(uint64_t id)
{
	struct relay_session *session = NULL;
	struct lttng_ht_node_u64 *node;
	struct lttng_ht_iter iter;

	rcu_read_lock();
	lttng_ht_lookup(sessions_ht, &id, &iter);
	node = lttng_ht_iter_get_node_u64(&iter);
	if (!node) {
		DBG("Session find by ID %" PRIu64 " id NOT found", id);
		goto end;
	}
	session = caa_container_of(node, struct relay_session, session_n);
	DBG("Session find by ID %" PRIu64 " id found", id);
	if (!session_get(session)) {
		session = NULL;
	}
end:
	rcu_read_unlock();
	return session;
}

static void rcu_destroy_session(struct rcu_head *rcu_head)
{
	struct relay_session *session =
			caa_container_of(rcu_head, struct relay_session,
				rcu_node);
	/*
	 * Since each trace has a reference on the session, it means
	 * that if we are at the point where we teardown the session, no
	 * trace belonging to that session exist at this point.
	 * Calling lttng_ht_destroy in call_rcu worker thread so we
	 * don't hold the RCU read-side lock while calling it.
	 */
	lttng_ht_destroy(session->ctf_traces_ht);
	free(session);
}

/*
 * Delete session from the given hash table.
 *
 * Return lttng ht del error code being 0 on success and 1 on failure.
 */
static int session_delete(struct relay_session *session)
{
	struct lttng_ht_iter iter;

	iter.iter.node = &session->session_n.node;
	return lttng_ht_del(sessions_ht, &iter);
}


static void destroy_session(struct relay_session *session)
{
	int ret;

	ret = session_delete(session);
	assert(!ret);
	lttng_trace_chunk_put(session->current_trace_chunk);
	ret = sessiond_trace_chunk_registry_session_destroyed(
			sessiond_trace_chunk_registry, session->sessiond_uuid);
	assert(!ret);
	lttng_trace_chunk_put(session->current_trace_chunk);
	session->current_trace_chunk = NULL;
	call_rcu(&session->rcu_node, rcu_destroy_session);
}

void session_release(struct urcu_ref *ref)
{
	struct relay_session *session =
			caa_container_of(ref, struct relay_session, ref);

	destroy_session(session);
}

void session_put(struct relay_session *session)
{
	rcu_read_lock();
	urcu_ref_put(&session->ref, session_release);
	rcu_read_unlock();
}

int session_close(struct relay_session *session)
{
	int ret = 0;
	struct ctf_trace *trace;
	struct lttng_ht_iter iter;
	struct relay_stream *stream;

	pthread_mutex_lock(&session->lock);
	DBG("closing session %" PRIu64 ": is conn already closed %d",
			session->id, session->connection_closed);
	session->connection_closed = true;
	pthread_mutex_unlock(&session->lock);

	rcu_read_lock();
	cds_lfht_for_each_entry(session->ctf_traces_ht->ht,
			&iter.iter, trace, node.node) {
		ret = ctf_trace_close(trace);
		if (ret) {
			goto rcu_unlock;
		}
	}
	cds_list_for_each_entry_rcu(stream, &session->recv_list,
			recv_node) {
		/* Close streams which have not been published yet. */
		try_stream_close(stream);
	}
rcu_unlock:
	rcu_read_unlock();
	if (ret) {
		return ret;
	}
	/* Put self-reference from create. */
	session_put(session);
	return ret;
}

int session_abort(struct relay_session *session)
{
	int ret = 0;

	if (!session) {
		return 0;
	}

	pthread_mutex_lock(&session->lock);
	DBG("aborting session %" PRIu64, session->id);
	session->aborted = true;
	pthread_mutex_unlock(&session->lock);
	return ret;
}

void print_sessions(void)
{
	struct lttng_ht_iter iter;
	struct relay_session *session;

	if (!sessions_ht) {
		return;
	}

	rcu_read_lock();
	cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
			session_n.node) {
		if (!session_get(session)) {
			continue;
		}
		DBG("session %p refcount %ld session %" PRIu64,
			session,
			session->ref.refcount,
			session->id);
		session_put(session);
	}
	rcu_read_unlock();
}
Commit	Line	Data
2f8f53af DG	1	/*
	2	* Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
	3	* David Goulet <dgoulet@efficios.com>
7591bab1	4	* 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2f8f53af DG	5	*
	6	* This program is free software; you can redistribute it and/or modify it
	7	* under the terms of the GNU General Public License, version 2 only, as
	8	* published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but WITHOUT
	11	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	12	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	13	* more details.
	14	*
	15	* You should have received a copy of the GNU General Public License along with
	16	* this program; if not, write to the Free Software Foundation, Inc., 51
	17	* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	18	*/
	19
6c1c0768	20	#define _LGPL_SOURCE
2a174661	21	#include <common/common.h>
1e791a74	22	#include <common/compat/uuid.h>
7591bab1	23	#include <urcu/rculist.h>
2a174661	24
7591bab1	25	#include "lttng-relayd.h"
2a174661	26	#include "ctf-trace.h"
2f8f53af	27	#include "session.h"
2a174661	28	#include "stream.h"
23c8ff50	29	#include "sessiond-trace-chunks.h"
2a174661 DG	30
	31	/* Global session id used in the session creation. */
	32	static uint64_t last_relay_session_id;
7591bab1	33	static pthread_mutex_t last_relay_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
2a174661	34
1e791a74 JG	35	static int session_set_anonymous_chunk(struct relay_session *session)
	36	{
	37	int ret = 0;
	38	struct lttng_trace_chunk *chunk = NULL;
	39	enum lttng_trace_chunk_status status;
	40	struct lttng_directory_handle output_directory;
	41
	42	ret = lttng_directory_handle_init(&output_directory, opt_output_path);
	43	if (ret) {
	44	goto end;
	45	}
	46
	47	chunk = lttng_trace_chunk_create_anonymous();
	48	if (!chunk) {
	49	goto end;
	50	}
	51
	52	status = lttng_trace_chunk_set_credentials_current_user(chunk);
	53	if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
	54	ret = -1;
	55	goto end;
	56	}
	57
	58	status = lttng_trace_chunk_set_as_owner(chunk, &output_directory);
	59	if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
	60	ret = -1;
	61	goto end;
	62	}
	63	session->current_trace_chunk = chunk;
	64	chunk = NULL;
	65	end:
	66	lttng_trace_chunk_put(chunk);
	67	lttng_directory_handle_fini(&output_directory);
	68	return ret;
	69	}
	70
2a174661 DG	71	/*
	72	* Create a new session by assigning a new session ID.
	73	*
	74	* Return allocated session or else NULL.
	75	*/
7591bab1 MD	76	struct relay_session session_create(const char session_name,
7591bab1 MD	77	const char *hostname, uint32_t live_timer,
23c8ff50	78	bool snapshot, const lttng_uuid sessiond_uuid,
1e791a74	79	uint64_t id_sessiond, uint64_t current_chunk_id,
23c8ff50	80	uint32_t major, uint32_t minor)
2a174661	81	{
23c8ff50	82	int ret;
2a174661 DG	83	struct relay_session *session;
	84
	85	session = zmalloc(sizeof(*session));
	86	if (!session) {
1e791a74	87	PERROR("Failed to allocate session");
2a174661 DG	88	goto error;
2a174661 DG	89	}
bb5d54e7 MD	90	if (lttng_strncpy(session->session_name, session_name,
bb5d54e7 MD	91	sizeof(session->session_name))) {
1e791a74	92	WARN("Session name exceeds maximal allowed length");
bb5d54e7 MD	93	goto error;
	94	}
	95	if (lttng_strncpy(session->hostname, hostname,
	96	sizeof(session->hostname))) {
1e791a74	97	WARN("Hostname exceeds maximal allowed length");
bb5d54e7 MD	98	goto error;
bb5d54e7 MD	99	}
2a174661 DG	100	session->ctf_traces_ht = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
2a174661 DG	101	if (!session->ctf_traces_ht) {
2a174661 DG	102	goto error;
	103	}
	104
7591bab1	105	pthread_mutex_lock(&last_relay_session_id_lock);
2a174661	106	session->id = ++last_relay_session_id;
7591bab1 MD	107	pthread_mutex_unlock(&last_relay_session_id_lock);
	108
	109	session->major = major;
	110	session->minor = minor;
2a174661	111	lttng_ht_node_init_u64(&session->session_n, session->id);
7591bab1 MD	112	urcu_ref_init(&session->ref);
	113	CDS_INIT_LIST_HEAD(&session->recv_list);
	114	pthread_mutex_init(&session->lock, NULL);
7591bab1 MD	115	pthread_mutex_init(&session->recv_list_lock, NULL);
7591bab1 MD	116
7591bab1 MD	117	session->live_timer = live_timer;
7591bab1 MD	118	session->snapshot = snapshot;
23c8ff50 JG	119	lttng_uuid_copy(session->sessiond_uuid, sessiond_uuid);
23c8ff50 JG	120
1e791a74 JG	121	if (id_sessiond) {
	122	LTTNG_OPTIONAL_SET(&session->id_sessiond, *id_sessiond);
	123	}
	124
23c8ff50 JG	125	ret = sessiond_trace_chunk_registry_session_created(
	126	sessiond_trace_chunk_registry, sessiond_uuid);
	127	if (ret) {
	128	goto error;
	129	}
7591bab1	130
1e791a74 JG	131	if (id_sessiond && current_chunk_id) {
	132	session->current_trace_chunk =
	133	sessiond_trace_chunk_registry_get_chunk(
	134	sessiond_trace_chunk_registry,
	135	session->sessiond_uuid,
	136	session->id_sessiond.value,
	137	*current_chunk_id);
	138	if (!session->current_trace_chunk) {
	139	char uuid_str[UUID_STR_LEN];
	140
	141	lttng_uuid_to_str(sessiond_uuid, uuid_str);
	142	ERR("Could not find trace chunk: sessiond = {%s}, sessiond session id = %" PRIu64 ", trace chunk id = %" PRIu64,
	143	uuid_str, *id_sessiond,
	144	*current_chunk_id);
	145	}
	146	} else if (!id_sessiond) {
	147	/*
	148	* Pre-2.11 peers will not announce trace chunks. An
	149	* anonymous trace chunk which will remain set for the
	150	* duration of the session is created.
	151	*/
	152	ret = session_set_anonymous_chunk(session);
	153	if (ret) {
	154	goto error;
	155	}
	156	}
	157
7591bab1	158	lttng_ht_add_unique_u64(sessions_ht, &session->session_n);
bb5d54e7	159	return session;
2a174661 DG	160
2a174661 DG	161	error:
1e791a74	162	session_put(session);
bb5d54e7	163	return NULL;
2a174661	164	}
2f8f53af	165
7591bab1 MD	166	/* Should be called with RCU read-side lock held. */
	167	bool session_get(struct relay_session *session)
	168	{
ce4d4083	169	return urcu_ref_get_unless_zero(&session->ref);
7591bab1 MD	170	}
7591bab1 MD	171
2f8f53af	172	/*
7591bab1 MD	173	* Lookup a session within the session hash table using the session id
	174	* as key. A session reference is taken when a session is returned.
	175	* session_put() must be called on that session.
2f8f53af DG	176	*
	177	* Return session or NULL if not found.
	178	*/
7591bab1	179	struct relay_session *session_get_by_id(uint64_t id)
2f8f53af DG	180	{
2f8f53af DG	181	struct relay_session *session = NULL;
2a174661	182	struct lttng_ht_node_u64 *node;
2f8f53af DG	183	struct lttng_ht_iter iter;
2f8f53af DG	184
7591bab1 MD	185	rcu_read_lock();
7591bab1 MD	186	lttng_ht_lookup(sessions_ht, &id, &iter);
2a174661	187	node = lttng_ht_iter_get_node_u64(&iter);
2f8f53af	188	if (!node) {
2a174661	189	DBG("Session find by ID %" PRIu64 " id NOT found", id);
2f8f53af DG	190	goto end;
	191	}
	192	session = caa_container_of(node, struct relay_session, session_n);
2a174661	193	DBG("Session find by ID %" PRIu64 " id found", id);
7591bab1 MD	194	if (!session_get(session)) {
	195	session = NULL;
	196	}
2f8f53af	197	end:
7591bab1	198	rcu_read_unlock();
2f8f53af DG	199	return session;
2f8f53af DG	200	}
2a174661	201
7591bab1 MD	202	static void rcu_destroy_session(struct rcu_head *rcu_head)
	203	{
	204	struct relay_session *session =
	205	caa_container_of(rcu_head, struct relay_session,
	206	rcu_node);
49e614cb MD	207	/*
	208	* Since each trace has a reference on the session, it means
	209	* that if we are at the point where we teardown the session, no
	210	* trace belonging to that session exist at this point.
	211	* Calling lttng_ht_destroy in call_rcu worker thread so we
	212	* don't hold the RCU read-side lock while calling it.
	213	*/
	214	lttng_ht_destroy(session->ctf_traces_ht);
7591bab1 MD	215	free(session);
	216	}
	217
2a174661 DG	218	/*
	219	* Delete session from the given hash table.
	220	*
	221	* Return lttng ht del error code being 0 on success and 1 on failure.
	222	*/
7591bab1	223	static int session_delete(struct relay_session *session)
2a174661 DG	224	{
	225	struct lttng_ht_iter iter;
	226
2a174661	227	iter.iter.node = &session->session_n.node;
7591bab1	228	return lttng_ht_del(sessions_ht, &iter);
2a174661 DG	229	}
2a174661 DG	230
7591bab1 MD	231
	232	static void destroy_session(struct relay_session *session)
	233	{
	234	int ret;
	235
	236	ret = session_delete(session);
	237	assert(!ret);
639ddf68	238	lttng_trace_chunk_put(session->current_trace_chunk);
23c8ff50 JG	239	ret = sessiond_trace_chunk_registry_session_destroyed(
	240	sessiond_trace_chunk_registry, session->sessiond_uuid);
	241	assert(!ret);
639ddf68 JG	242	lttng_trace_chunk_put(session->current_trace_chunk);
639ddf68 JG	243	session->current_trace_chunk = NULL;
7591bab1 MD	244	call_rcu(&session->rcu_node, rcu_destroy_session);
	245	}
	246
	247	void session_release(struct urcu_ref *ref)
2a174661	248	{
7591bab1 MD	249	struct relay_session *session =
7591bab1 MD	250	caa_container_of(ref, struct relay_session, ref);
2a174661	251
7591bab1 MD	252	destroy_session(session);
7591bab1 MD	253	}
2a174661	254
7591bab1 MD	255	void session_put(struct relay_session *session)
	256	{
	257	rcu_read_lock();
7591bab1	258	urcu_ref_put(&session->ref, session_release);
7591bab1	259	rcu_read_unlock();
2a174661 DG	260	}
2a174661 DG	261
7591bab1	262	int session_close(struct relay_session *session)
2a174661 DG	263	{
2a174661 DG	264	int ret = 0;
7591bab1 MD	265	struct ctf_trace *trace;
	266	struct lttng_ht_iter iter;
	267	struct relay_stream *stream;
	268
	269	pthread_mutex_lock(&session->lock);
	270	DBG("closing session %" PRIu64 ": is conn already closed %d",
	271	session->id, session->connection_closed);
7591bab1	272	session->connection_closed = true;
7591bab1	273	pthread_mutex_unlock(&session->lock);
2a174661	274
7591bab1 MD	275	rcu_read_lock();
	276	cds_lfht_for_each_entry(session->ctf_traces_ht->ht,
	277	&iter.iter, trace, node.node) {
	278	ret = ctf_trace_close(trace);
	279	if (ret) {
	280	goto rcu_unlock;
2a174661 DG	281	}
2a174661 DG	282	}
7591bab1 MD	283	cds_list_for_each_entry_rcu(stream, &session->recv_list,
7591bab1 MD	284	recv_node) {
bda7c7b9 JG	285	/* Close streams which have not been published yet. */
bda7c7b9 JG	286	try_stream_close(stream);
7591bab1 MD	287	}
	288	rcu_unlock:
	289	rcu_read_unlock();
	290	if (ret) {
	291	return ret;
	292	}
	293	/* Put self-reference from create. */
	294	session_put(session);
	295	return ret;
2a174661 DG	296	}
2a174661 DG	297
98ba050e JR	298	int session_abort(struct relay_session *session)
	299	{
	300	int ret = 0;
	301
	302	if (!session) {
	303	return 0;
	304	}
	305
	306	pthread_mutex_lock(&session->lock);
	307	DBG("aborting session %" PRIu64, session->id);
98ba050e	308	session->aborted = true;
98ba050e JR	309	pthread_mutex_unlock(&session->lock);
	310	return ret;
	311	}
	312
7591bab1	313	void print_sessions(void)
2a174661	314	{
2a174661	315	struct lttng_ht_iter iter;
7591bab1	316	struct relay_session *session;
2a174661	317
ce3f3ba3 JG	318	if (!sessions_ht) {
	319	return;
	320	}
	321
2a174661	322	rcu_read_lock();
7591bab1 MD	323	cds_lfht_for_each_entry(sessions_ht->ht, &iter.iter, session,
	324	session_n.node) {
	325	if (!session_get(session)) {
	326	continue;
	327	}
	328	DBG("session %p refcount %ld session %" PRIu64,
	329	session,
	330	session->ref.refcount,
	331	session->id);
	332	session_put(session);
2a174661	333	}
2a174661	334	rcu_read_unlock();
2a174661	335	}