X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fsession.h;h=e6ed40cc2927f624ce3255492a91e129edcb5a8c;hp=19dabb727179bb23a64e2b5cf3a1bba8a5f4ffc3;hb=d7b377ed1acd4043bde353d99122e0e56fa4e975;hpb=82b69413fa2d05d8643c4fb900b88f5d41206cfc diff --git a/src/bin/lttng-sessiond/session.h b/src/bin/lttng-sessiond/session.h index 19dabb727..e6ed40cc2 100644 --- a/src/bin/lttng-sessiond/session.h +++ b/src/bin/lttng-sessiond/session.h @@ -1,18 +1,8 @@ /* - * Copyright (C) 2011 - David Goulet + * Copyright (C) 2011 David Goulet * - * 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 @@ -23,6 +13,7 @@ #include #include +#include #include #include #include @@ -33,6 +24,11 @@ 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 * @@ -71,7 +67,10 @@ struct ltt_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; @@ -146,61 +145,6 @@ struct ltt_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. @@ -218,28 +162,64 @@ struct ltt_session { * 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) last_trace_chunk_id; + 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); @@ -252,7 +232,7 @@ void session_get_net_consumer_ports( 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); @@ -260,15 +240,42 @@ 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); -enum lttng_error_code session_switch_trace_chunk(struct ltt_session *session, +/* 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 *current_trace_chunk); + 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 */