src/bin/lttng-sessiond/rotate.h

   1 /*
   2  * Copyright (C) 2017 - Julien Desfossez <jdesfossez@efficios.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License, version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 51
  15  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  16  */
  17
  18 #ifndef ROTATE_H
  19 #define ROTATE_H
  20
  21 #include <lttng/notification/channel-internal.h>
  22 #include "rotation-thread.h"
  23
  24 /*
  25  * Key in channel_pending_rotate_ht to map a channel to a
  26  * struct rotation_channel_info.
  27  */
  28 struct rotation_channel_key {
  29         uint64_t key;
  30         enum lttng_domain_type domain;
  31 };
  32
  33 /*
  34  * Added in channel_pending_rotate_ht everytime we start the rotation of a
  35  * channel. The consumer notifies the rotation thread with the channel_key to
  36  * inform a rotation is complete, we use that information to lookup the related
  37  * session from channel_pending_rotate_ht.
  38  */
  39 struct rotation_channel_info {
  40         uint64_t session_id;
  41         struct rotation_channel_key channel_key;
  42         struct cds_lfht_node rotate_channels_ht_node;
  43 };
  44
  45
  46 extern struct cds_lfht *channel_pending_rotate_ht;
  47 extern struct lttng_notification_channel *rotate_notification_channel;
  48
  49 unsigned long hash_channel_key(struct rotation_channel_key *key);
  50
  51 /* session lock must be held by this function's caller. */
  52 int rename_complete_chunk(struct ltt_session *session, time_t ts);
  53
  54 int relay_rotate_pending(struct ltt_session *session, uint64_t chunk_id);
  55
  56 /*
  57  * When we start the rotation of a channel, we add its information in
  58  * channel_pending_rotate_ht. This is called in the context of
  59  * thread_manage_client when the client asks for a rotation, in the context
  60  * of the sessiond_timer thread when periodic rotations are enabled and from
  61  * the rotation_thread when size-based rotations are enabled.
  62  */
  63 int rotate_add_channel_pending(uint64_t key, enum lttng_domain_type domain,
  64                 struct ltt_session *session);
  65
  66 /*
  67  * Subscribe/unsubscribe the notification_channel from the rotation_thread to
  68  * session usage notifications to perform size-based rotations.
  69  */
  70 int subscribe_session_consumed_size_rotation(struct ltt_session *session,
  71                 uint64_t size,
  72                 struct notification_thread_handle *notification_thread_handle);
  73 int unsubscribe_session_consumed_size_rotation(struct ltt_session *session,
  74                 struct notification_thread_handle *notification_thread_handle);
  75
  76 #endif /* ROTATE_H */