| 1 | /* |
| 2 | * Copyright (C) 2012 - Julien Desfossez <jdesfossez@efficios.com> |
| 3 | * David Goulet <dgoulet@efficios.com> |
| 4 | * |
| 5 | * This program is free software; you can redistribute it and/or modify |
| 6 | * it under the terms of the GNU General Public License, version 2 only, |
| 7 | * as published by the Free Software Foundation. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 12 | * more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License along |
| 15 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 16 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 17 | */ |
| 18 | |
| 19 | #ifndef LTTNG_RELAYD_H |
| 20 | #define LTTNG_RELAYD_H |
| 21 | |
| 22 | #define _LGPL_SOURCE |
| 23 | #include <limits.h> |
| 24 | #include <urcu.h> |
| 25 | #include <urcu/wfqueue.h> |
| 26 | |
| 27 | #include <common/hashtable/hashtable.h> |
| 28 | #include <common/index/ctf-index.h> |
| 29 | |
| 30 | #include "ctf-trace.h" |
| 31 | |
| 32 | /* |
| 33 | * Queue used to enqueue relay requests |
| 34 | */ |
| 35 | struct relay_cmd_queue { |
| 36 | struct cds_wfq_queue queue; |
| 37 | int32_t futex; |
| 38 | }; |
| 39 | |
| 40 | enum connection_type { |
| 41 | RELAY_DATA = 1, |
| 42 | RELAY_CONTROL = 2, |
| 43 | RELAY_VIEWER_COMMAND = 3, |
| 44 | RELAY_VIEWER_NOTIFICATION = 4, |
| 45 | }; |
| 46 | |
| 47 | /* |
| 48 | * Represents a session for the relay point of view |
| 49 | */ |
| 50 | struct relay_session { |
| 51 | /* |
| 52 | * This session id is used to identify a set of stream to a tracing session |
| 53 | * but also make sure we have a unique session id associated with a session |
| 54 | * daemon which can provide multiple data source. |
| 55 | */ |
| 56 | uint64_t id; |
| 57 | struct lttcomm_sock *sock; |
| 58 | char session_name[NAME_MAX]; |
| 59 | char hostname[HOST_NAME_MAX]; |
| 60 | uint32_t live_timer; |
| 61 | struct lttng_ht_node_ulong session_n; |
| 62 | struct rcu_head rcu_node; |
| 63 | uint32_t viewer_attached; |
| 64 | uint32_t stream_count; |
| 65 | /* Tell if this session is for a snapshot or not. */ |
| 66 | unsigned int snapshot:1; |
| 67 | |
| 68 | /* |
| 69 | * Indicate version protocol for this session. This is especially useful |
| 70 | * for the data thread that has no idea which version it operates on since |
| 71 | * linking control/data sockets is non trivial. |
| 72 | */ |
| 73 | uint64_t minor; |
| 74 | uint64_t major; |
| 75 | }; |
| 76 | |
| 77 | /* |
| 78 | * Represents a stream in the relay |
| 79 | */ |
| 80 | struct relay_stream { |
| 81 | uint64_t stream_handle; |
| 82 | uint64_t prev_seq; /* previous data sequence number encountered */ |
| 83 | struct lttng_ht_node_ulong stream_n; |
| 84 | struct relay_session *session; |
| 85 | struct rcu_head rcu_node; |
| 86 | int fd; |
| 87 | /* FD on which to write the index data. */ |
| 88 | int index_fd; |
| 89 | /* FD on which to read the index data for the viewer. */ |
| 90 | int read_index_fd; |
| 91 | |
| 92 | char *path_name; |
| 93 | char *channel_name; |
| 94 | /* on-disk circular buffer of tracefiles */ |
| 95 | uint64_t tracefile_size; |
| 96 | uint64_t tracefile_size_current; |
| 97 | uint64_t tracefile_count; |
| 98 | uint64_t tracefile_count_current; |
| 99 | /* To inform the viewer up to where it can go back in time. */ |
| 100 | uint64_t oldest_tracefile_id; |
| 101 | |
| 102 | uint64_t total_index_received; |
| 103 | struct relay_viewer_stream *viewer_stream; |
| 104 | uint64_t last_net_seq_num; |
| 105 | |
| 106 | /* |
| 107 | * This node is added to the *control* connection hash table and the |
| 108 | * pointer is copied in here so we can access it when deleting this object. |
| 109 | * When deleting this, the ctf trace ht MUST NOT be destroyed. This happens |
| 110 | * at connection deletion. |
| 111 | */ |
| 112 | struct lttng_ht_node_str ctf_trace_node; |
| 113 | struct lttng_ht *ctf_traces_ht; |
| 114 | |
| 115 | /* |
| 116 | * To protect from concurrent read/update between the |
| 117 | * streaming-side and the viewer-side. |
| 118 | * This lock must be held, we reading/updating the |
| 119 | * ctf_trace pointer. |
| 120 | */ |
| 121 | pthread_mutex_t lock; |
| 122 | |
| 123 | struct ctf_trace *ctf_trace; |
| 124 | /* |
| 125 | * If the stream is inactive, this field is updated with the live beacon |
| 126 | * timestamp end, when it is active, this field == -1ULL. |
| 127 | */ |
| 128 | uint64_t beacon_ts_end; |
| 129 | /* |
| 130 | * To protect the update of the close_write_flag and the checks of |
| 131 | * the tracefile_count_current. |
| 132 | * It is taken before checking whenever we need to know if the |
| 133 | * writer and reader are working in the same tracefile. |
| 134 | */ |
| 135 | pthread_mutex_t viewer_stream_rotation_lock; |
| 136 | |
| 137 | /* Information telling us when to close the stream */ |
| 138 | unsigned int close_flag:1; |
| 139 | /* Indicate if the stream was initialized for a data pending command. */ |
| 140 | unsigned int data_pending_check_done:1; |
| 141 | unsigned int metadata_flag:1; |
| 142 | /* |
| 143 | * To detect when we start overwriting old data, it is used to |
| 144 | * update the oldest_tracefile_id. |
| 145 | */ |
| 146 | unsigned int tracefile_overwrite:1; |
| 147 | }; |
| 148 | |
| 149 | /* |
| 150 | * Shadow copy of the relay_stream structure for the viewer side. The only |
| 151 | * fields updated by the writer (streaming side) after allocation are : |
| 152 | * total_index_received and close_flag. Everything else is updated by the |
| 153 | * reader (viewer side). |
| 154 | */ |
| 155 | struct relay_viewer_stream { |
| 156 | uint64_t stream_handle; |
| 157 | uint64_t session_id; |
| 158 | int read_fd; |
| 159 | int index_read_fd; |
| 160 | char *path_name; |
| 161 | char *channel_name; |
| 162 | uint64_t last_sent_index; |
| 163 | uint64_t total_index_received; |
| 164 | uint64_t tracefile_count; |
| 165 | uint64_t tracefile_count_current; |
| 166 | /* Stop after reading this tracefile. */ |
| 167 | uint64_t tracefile_count_last; |
| 168 | struct lttng_ht_node_u64 stream_n; |
| 169 | struct rcu_head rcu_node; |
| 170 | struct ctf_trace *ctf_trace; |
| 171 | /* |
| 172 | * This lock blocks only when the writer is about to start overwriting |
| 173 | * a file currently read by the reader. |
| 174 | * |
| 175 | * This is nested INSIDE the viewer_stream_rotation_lock. |
| 176 | */ |
| 177 | pthread_mutex_t overwrite_lock; |
| 178 | /* Information telling us if the stream is a metadata stream. */ |
| 179 | unsigned int metadata_flag:1; |
| 180 | /* |
| 181 | * Information telling us that the stream is closed in write, so |
| 182 | * we don't expect new indexes and we can read up to EOF. |
| 183 | */ |
| 184 | unsigned int close_write_flag:1; |
| 185 | /* |
| 186 | * If the streaming side closes a FD in use in the viewer side, |
| 187 | * it sets this flag to inform that it is a normal error. |
| 188 | */ |
| 189 | unsigned int abort_flag:1; |
| 190 | }; |
| 191 | |
| 192 | /* |
| 193 | * Internal structure to map a socket with the corresponding session. |
| 194 | * A hashtable indexed on the socket FD is used for the lookups. |
| 195 | */ |
| 196 | struct relay_command { |
| 197 | struct lttcomm_sock *sock; |
| 198 | struct relay_session *session; |
| 199 | struct cds_wfq_node node; |
| 200 | struct lttng_ht_node_ulong sock_n; |
| 201 | struct rcu_head rcu_node; |
| 202 | enum connection_type type; |
| 203 | unsigned int version_check_done:1; |
| 204 | /* protocol version to use for this session */ |
| 205 | uint32_t major; |
| 206 | uint32_t minor; |
| 207 | struct lttng_ht *ctf_traces_ht; /* indexed by path name */ |
| 208 | uint64_t session_id; |
| 209 | }; |
| 210 | |
| 211 | struct relay_local_data { |
| 212 | struct lttng_ht *sessions_ht; |
| 213 | }; |
| 214 | |
| 215 | extern char *opt_output_path; |
| 216 | |
| 217 | extern struct lttng_ht *relay_streams_ht; |
| 218 | extern struct lttng_ht *viewer_streams_ht; |
| 219 | extern struct lttng_ht *indexes_ht; |
| 220 | |
| 221 | extern const char *tracing_group_name; |
| 222 | |
| 223 | struct relay_stream *relay_stream_find_by_id(uint64_t stream_id); |
| 224 | |
| 225 | #endif /* LTTNG_RELAYD_H */ |