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 #include <common/trace-chunk.h>
  30 #include <common/optional.h>
  31 #include <common/buffer-view.h>
  32
  33 #include "session.h"
  34 #include "stream-fd.h"
  35 #include "tracefile-array.h"
  36
  37 struct lttcomm_relayd_index;
  38
  39 struct relay_stream_rotation {
  40         /*
  41          * Indicates if the stream's data and index have been rotated. A
  42          * rotation is considered completed when both rotations have occurred.
  43          */
  44         bool data_rotated;
  45         bool index_rotated;
  46         /*
  47          * Sequence number of the first packet of the new trace chunk to which
  48          * the stream is rotating.
  49          */
  50         uint64_t seq_num;
  51         struct lttng_trace_chunk *next_trace_chunk;
  52 };
  53
  54 /*
  55  * Represents a stream in the relay
  56  */
  57 struct relay_stream {
  58         uint64_t stream_handle;
  59
  60         struct urcu_ref ref;
  61         /* Back reference to trace. Protected by refcount on trace object. */
  62         struct ctf_trace *trace;
  63
  64         /*
  65          * To protect from concurrent read/update. The viewer stream
  66          * lock nests inside the stream lock. The stream lock nests
  67          * inside the ctf_trace lock.
  68          */
  69         pthread_mutex_t lock;
  70         /* previous data sequence number written to disk. */
  71         uint64_t prev_data_seq;
  72         /* previous index sequence number written to disk. */
  73         uint64_t prev_index_seq;
  74         /* seq num to encounter before closing. */
  75         uint64_t last_net_seq_num;
  76
  77         /* FD on which to write the stream data. */
  78         struct stream_fd *stream_fd;
  79         /* index file on which to write the index data. */
  80         struct lttng_index_file *index_file;
  81
  82         char *path_name;
  83         char *channel_name;
  84
  85         /* On-disk circular buffer of tracefiles. */
  86         uint64_t tracefile_size;
  87         uint64_t tracefile_size_current;
  88         /* Max number of trace files for this stream. */
  89         uint64_t tracefile_count;
  90         /*
  91          * Index of the currently active file for this stream's on-disk
  92          * ring buffer.
  93          */
  94         uint64_t tracefile_current_index;
  95         /*
  96          * Indicates that the on-disk buffer has wrapped around. Stream
  97          * files shall be unlinked before being opened after this has occurred.
  98          */
  99         bool tracefile_wrapped_around;
 100
 101         /*
 102          * Position in the tracefile where we have the full index also on disk.
 103          */
 104         uint64_t pos_after_last_complete_data_index;
 105
 106         /*
 107          * Counts the number of received indexes. The "tag" associated
 108          * with an index is taken before incrementing this seqcount.
 109          * Therefore, the sequence tag associated with the last index
 110          * received is always index_received_seqcount - 1.
 111          */
 112         uint64_t index_received_seqcount;
 113
 114         /*
 115          * Tracefile array is an index of the stream trace files,
 116          * indexed by position. It allows keeping track of the oldest
 117          * available indexes when overwriting trace files in tracefile
 118          * rotation.
 119          */
 120         struct tracefile_array *tfa;
 121
 122         bool closed;            /* Stream is closed. */
 123         bool close_requested;   /* Close command has been received. */
 124
 125         /*
 126          * Counts number of indexes in indexes_ht. Redundant info.
 127          * Protected by stream lock.
 128          */
 129         int indexes_in_flight;
 130         struct lttng_ht *indexes_ht;
 131
 132         /*
 133          * If the stream is inactive, this field is updated with the
 134          * live beacon timestamp end, when it is active, this
 135          * field == -1ULL.
 136          */
 137         uint64_t beacon_ts_end;
 138
 139         /* CTF stream ID, -1ULL when unset (first packet not received yet). */
 140         uint64_t ctf_stream_id;
 141
 142         /* Indicate if the stream was initialized for a data pending command. */
 143         bool data_pending_check_done;
 144
 145         /* Is this stream a metadata stream ? */
 146         bool is_metadata;
 147         /* Amount of metadata received (bytes). */
 148         uint64_t metadata_received;
 149
 150         /*
 151          * Member of the stream list in struct ctf_trace.
 152          * Updates are protected by the stream_list_lock.
 153          * Traversals are protected by RCU.
 154          */
 155         struct cds_list_head stream_node;
 156         /*
 157          * Temporary list belonging to the connection until all streams
 158          * are received for that connection.
 159          * Member of the stream recv list in the connection.
 160          * Updates are protected by the stream_recv_list_lock.
 161          * Traversals are protected by RCU.
 162          */
 163         bool in_recv_list;
 164         struct cds_list_head recv_node;
 165         /* Protected by session lock. */
 166         bool published;
 167         /*
 168          * Node of stream within global stream hash table.
 169          */
 170         struct lttng_ht_node_u64 node;
 171         bool in_stream_ht;              /* is stream in stream hash table. */
 172         struct rcu_head rcu_node;       /* For call_rcu teardown. */
 173         /*
 174          * The trace chunk to which the file currently being produced (if any)
 175          * belongs.
 176          */
 177         struct lttng_trace_chunk *trace_chunk;
 178         LTTNG_OPTIONAL(struct relay_stream_rotation) ongoing_rotation;
 179 };
 180
 181 struct relay_stream *stream_create(struct ctf_trace *trace,
 182         uint64_t stream_handle, char *path_name,
 183         char *channel_name, uint64_t tracefile_size,
 184         uint64_t tracefile_count);
 185
 186 struct relay_stream *stream_get_by_id(uint64_t stream_id);
 187 bool stream_get(struct relay_stream *stream);
 188 void stream_put(struct relay_stream *stream);
 189 int stream_rotate_output_files(struct relay_session *session,
 190                 struct relay_stream *stream);
 191 int stream_set_pending_rotation(struct relay_stream *stream,
 192                 struct lttng_trace_chunk *next_trace_chunk,
 193                 uint64_t rotation_sequence_number);
 194 void try_stream_close(struct relay_stream *stream);
 195 void stream_publish(struct relay_stream *stream);
 196 int stream_init_packet(struct relay_stream *stream, size_t packet_size,
 197                 bool *file_rotated);
 198 int stream_write(struct relay_stream *stream,
 199                 const struct lttng_buffer_view *packet, size_t padding_len);
 200 /* Called after the reception of a complete data packet. */
 201 int stream_update_index(struct relay_stream *stream, uint64_t net_seq_num,
 202                 bool rotate_index, bool *flushed, uint64_t total_size);
 203 int stream_complete_packet(struct relay_stream *stream,
 204                 size_t packet_total_size, uint64_t sequence_number,
 205                 bool index_flushed);
 206 /* Index info is in host endianness. */
 207 int stream_add_index(struct relay_stream *stream,
 208                 const struct lttcomm_relayd_index *index_info);
 209 int stream_reset_file(struct relay_stream *stream);
 210
 211 void print_relay_streams(void);
 212
 213 #endif /* _STREAM_H */