/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
*
- * 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.
+ * SPDX-License-Identifier: GPL-2.0-only
*
- * 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.
*/
#ifndef _LTT_SESSION_H
#include <urcu/list.h>
#include <common/hashtable/hashtable.h>
+#include <common/dynamic-array.h>
#include <lttng/rotation.h>
#include <lttng/location.h>
+#include <lttng/lttng-error.h>
#include "snapshot.h"
#include "trace-kernel.h"
struct ltt_ust_session;
+typedef void (*ltt_session_destroy_notifier)(const struct ltt_session *session,
+ void *user_data);
+typedef void (*ltt_session_clear_notifier)(const struct ltt_session *session,
+ void *user_data);
+
/*
* Tracing session list
*
struct ltt_session {
char name[NAME_MAX];
bool has_auto_generated_name;
+ bool name_contains_creation_time;
char hostname[HOST_NAME_MAX]; /* Local hostname. */
+ /* Path of the last closed chunk. */
+ char last_chunk_path[LTTNG_PATH_MAX];
time_t creation_time;
struct ltt_kernel_session *kernel_session;
struct ltt_ust_session *ust_session;
* Node in ltt_sessions_ht_by_id.
*/
struct lttng_ht_node_u64 node;
- /*
- * The current archive id corresponds to the number of session rotations
- * that have occurred for this session. The archive id
- * is used to tag the "generation" of a stream. This tag allows the
- * consumer and relay daemons to track when a given stream was created
- * during the lifetime of a session.
- *
- * For instance, if a stream is created after a session rotation was
- * launched, the consumer and relay daemons must not check its position
- * to determine if that specific session rotation was completed. It is
- * implicitly "completed" since the stream appeared _after_ the session
- * rotation was initiated.
- */
- uint64_t current_archive_id;
- /*
- * Rotation is considered pending between the time it is launched up
- * until the moment when the data has been writen at the destination
- * and the trace archive has been renamed.
- *
- * When tracing locally, only 'rotation_pending_local' is used since
- * no remote checks are needed. However, when tracing to a relay daemon,
- * a second check is needed to ensure that the data has been
- * commited at the remote destination.
- */
- bool rotation_pending_local;
- bool rotation_pending_relay;
- /* Current state of a rotation. */
- enum lttng_rotation_state rotation_state;
- struct {
- /*
- * When the rotation is in progress, the temporary path name is
- * stored here. When the rotation is complete, the final path name
- * is here and can be queried with the rotate_pending call.
- */
- char current_rotate_path[LTTNG_PATH_MAX];
- /*
- * The path where the consumer is currently writing after the first
- * session rotation.
- */
- char active_tracing_path[LTTNG_PATH_MAX];
- } rotation_chunk;
- /*
- * The timestamp of the beginning of the previous chunk. For the
- * first chunk, this is the "lttng start" timestamp. For the
- * subsequent ones, this copies the current_chunk_start_ts value when
- * a new rotation starts. This value is used to set the name of a
- * complete chunk directory, ex: "last_chunk_start_ts-now()".
- */
- time_t last_chunk_start_ts;
- /*
- * This is the timestamp when a new chunk starts. When a new rotation
- * starts, we copy this value to last_chunk_start_ts and replace it
- * with the current timestamp.
- */
- time_t current_chunk_start_ts;
/*
* Timer to check periodically if a relay and/or consumer has completed
* the last rotation.
* Keep a state if this session was rotated after the last stop command.
* We only allow one rotation after a stop. At destroy, we also need to
* know if a rotation occurred since the last stop to rename the current
- * chunk.
+ * chunk. After a stop followed by rotate, all subsequent clear
+ * (without prior start) will succeed, but will be effect-less.
*/
bool rotated_after_last_stop;
+ /*
+ * Track whether the session was cleared after last stop. All subsequent
+ * clear (without prior start) will succeed, but will be effect-less. A
+ * subsequent rotate (without prior start) will return an error.
+ */
+ bool cleared_after_last_stop;
+ /*
+ * True if the session has had an explicit non-quiet rotation.
+ */
+ bool rotated;
/*
* Condition and trigger for size-based rotations.
*/
struct lttng_condition *rotate_condition;
struct lttng_trigger *rotate_trigger;
+ LTTNG_OPTIONAL(uint64_t) most_recent_chunk_id;
+ struct lttng_trace_chunk *current_trace_chunk;
+ struct lttng_trace_chunk *chunk_being_archived;
+ /* Current state of a rotation. */
+ enum lttng_rotation_state rotation_state;
+ bool quiet_rotation;
+ char *last_archived_chunk_name;
+ LTTNG_OPTIONAL(uint64_t) last_archived_chunk_id;
+ struct lttng_dynamic_array destroy_notifiers;
+ struct lttng_dynamic_array clear_notifiers;
+ /* Session base path override. Set non-null. */
+ char *base_path;
};
-/* Prototypes */
enum lttng_error_code session_create(const char *name, uid_t uid, gid_t gid,
struct ltt_session **out_session);
void session_lock(struct ltt_session *session);
+void session_unlock(struct ltt_session *session);
+
+/*
+ * The session list lock covers more ground than its name implies. While
+ * it does protect against concurent mutations of the session list, it is
+ * also used as a multi-session lock when synchronizing newly-registered
+ * 'user space tracer' and 'agent' applications.
+ *
+ * In other words, it prevents session configurations from changing while they
+ * are being transmitted to the various applications.
+ */
void session_lock_list(void);
int session_trylock_list(void);
-void session_unlock(struct ltt_session *session);
void session_unlock_list(void);
void session_destroy(struct ltt_session *session);
+int session_add_destroy_notifier(struct ltt_session *session,
+ ltt_session_destroy_notifier notifier, void *user_data);
+
+int session_add_clear_notifier(struct ltt_session *session,
+ ltt_session_clear_notifier notifier, void *user_data);
+void session_notify_clear(struct ltt_session *session);
bool session_get(struct ltt_session *session);
void session_put(struct ltt_session *session);
const struct ltt_session *session,
uint16_t *control_port, uint16_t *data_port);
struct lttng_trace_archive_location *session_get_trace_archive_location(
- struct ltt_session *session);
+ const struct ltt_session *session);
struct ltt_session *session_find_by_name(const char *name);
struct ltt_session *session_find_by_id(uint64_t id);
struct ltt_session_list *session_get_list(void);
void session_list_wait_empty(void);
-int session_access_ok(struct ltt_session *session, uid_t uid, gid_t gid);
+bool session_access_ok(struct ltt_session *session, uid_t uid);
int session_reset_rotation_state(struct ltt_session *session,
enum lttng_rotation_state result);
+/* Create a new trace chunk object from the session's configuration. */
+struct lttng_trace_chunk *session_create_new_trace_chunk(
+ const struct ltt_session *session,
+ const struct consumer_output *consumer_output_override,
+ const char *session_base_path_override,
+ const char *chunk_name_override);
+
+/*
+ * Set `new_trace_chunk` as the session's current trace chunk. A reference
+ * to `new_trace_chunk` is acquired by the session. The chunk is created
+ * on remote peers (consumer and relay daemons).
+ *
+ * A reference to the session's current trace chunk is returned through
+ * `current_session_trace_chunk` on success.
+ */
+int session_set_trace_chunk(struct ltt_session *session,
+ struct lttng_trace_chunk *new_trace_chunk,
+ struct lttng_trace_chunk **current_session_trace_chunk);
+
+/*
+ * Close a chunk on the remote peers of a session. Has no effect on the
+ * ltt_session itself.
+ */
+int session_close_trace_chunk(struct ltt_session *session,
+ struct lttng_trace_chunk *trace_chunk,
+ enum lttng_trace_chunk_command_type close_command,
+ char *path);
+
+/* Open a packet in all channels of a given session. */
+enum lttng_error_code session_open_packets(struct ltt_session *session);
+
+bool session_output_supports_trace_chunks(const struct ltt_session *session);
+
#endif /* _LTT_SESSION_H */
projects / lttng-tools.git / blobdiff