src/bin/lttng-relayd/stream.h

   1 #ifndef _STREAM_H
   2 #define _STREAM_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
  28 #include <common/hashtable/hashtable.h>
  29
  30 #include "session.h"
  31 #include "stream-fd.h"
  32
  33 /*
  34  * Represents a stream in the relay
  35  */
  36 struct relay_stream {
  37         uint64_t stream_handle;
  38
  39         /*
  40          * reflock used to synchronize the closing of this stream.
  41          * stream reflock nests inside viewer stream reflock.
  42          * stream reflock nests inside index reflock.
  43          */
  44         pthread_mutex_t reflock;
  45         struct urcu_ref ref;
  46         /* Back reference to trace. Protected by refcount on trace object. */
  47         struct ctf_trace *trace;
  48
  49         /*
  50          * To protect from concurrent read/update. The viewer stream
  51          * lock nests inside the stream lock. The stream lock nests
  52          * inside the ctf_trace lock.
  53          */
  54         pthread_mutex_t lock;
  55         uint64_t prev_seq;              /* previous data sequence number encountered. */
  56         uint64_t last_net_seq_num;      /* seq num to encounter before closing. */
  57
  58         /* FD on which to write the stream data. */
  59         struct stream_fd *stream_fd;
  60         /* FD on which to write the index data. */
  61         struct stream_fd *index_fd;
  62
  63         char *path_name;
  64         char *channel_name;
  65
  66         /* On-disk circular buffer of tracefiles. */
  67         uint64_t tracefile_size;
  68         uint64_t tracefile_size_current;
  69         uint64_t tracefile_count;
  70         uint64_t current_tracefile_id;
  71
  72         uint64_t current_tracefile_seq; /* Free-running counter. */
  73         uint64_t oldest_tracefile_seq;  /* Free-running counter. */
  74
  75         /* To inform the viewer up to where it can go back in time. */
  76         uint64_t oldest_tracefile_id;
  77
  78         uint64_t total_index_received;
  79
  80         bool closed;    /* Stream is closed. */
  81
  82         /*
  83          * Counts number of indexes in indexes_ht. Redundant info.
  84          * Protected by stream lock.
  85          */
  86         int indexes_in_flight;
  87         struct lttng_ht *indexes_ht;
  88
  89         /*
  90          * If the stream is inactive, this field is updated with the
  91          * live beacon timestamp end, when it is active, this
  92          * field == -1ULL.
  93          */
  94         uint64_t beacon_ts_end;
  95
  96         /* CTF stream ID, -1ULL when unset (first packet not received yet). */
  97         uint64_t ctf_stream_id;
  98
  99         /* Indicate if the stream was initialized for a data pending command. */
 100         bool data_pending_check_done;
 101
 102         /* Is this stream a metadata stream ? */
 103         int32_t is_metadata;
 104         /* Amount of metadata received (bytes). */
 105         uint64_t metadata_received;
 106
 107         /*
 108          * Member of the stream list in struct ctf_trace.
 109          * Updates are protected by the stream_list_lock.
 110          * Traversals are protected by RCU.
 111          */
 112         struct cds_list_head stream_node;
 113         /*
 114          * Temporary list belonging to the connection until all streams
 115          * are received for that connection.
 116          * Member of the stream recv list in the connection.
 117          * Updates are protected by the stream_recv_list_lock.
 118          * Traversals are protected by RCU.
 119          */
 120         bool in_recv_list;
 121         struct cds_list_head recv_node;
 122         bool published; /* Protected by session lock. */
 123         /*
 124          * Node of stream within global stream hash table.
 125          */
 126         struct lttng_ht_node_u64 node;
 127         struct rcu_head rcu_node;       /* For call_rcu teardown. */
 128 };
 129
 130 struct relay_stream *stream_create(struct ctf_trace *trace,
 131         uint64_t stream_handle, char *path_name,
 132         char *channel_name, uint64_t tracefile_size,
 133         uint64_t tracefile_count);
 134
 135 struct relay_stream *stream_get_by_id(uint64_t stream_id);
 136 bool stream_get(struct relay_stream *stream);
 137 void stream_put(struct relay_stream *stream);
 138 void stream_close(struct relay_stream *stream);
 139 void stream_publish(struct relay_stream *stream);
 140 void print_relay_streams(void);
 141
 142 #endif /* _STREAM_H */