relayd: implement file and session rotation on top of trace chunks

[lttng-tools.git] / src / bin / lttng-relayd / stream.h

diff --git a/src/bin/lttng-relayd/stream.h b/src/bin/lttng-relayd/stream.h
index dfe15f1a045f28d9bde46a56a50603bf352710a9..b8d14ecfb8cb0d07b40553456bc0fae86a7d5f4e 100644 (file)
--- a/src/bin/lttng-relayd/stream.h
+++ b/src/bin/lttng-relayd/stream.h
@@ -27,11 +27,30 @@
 
 #include <common/hashtable/hashtable.h>
 #include <common/trace-chunk.h>
+#include <common/optional.h>
+#include <common/buffer-view.h>
 
 #include "session.h"
 #include "stream-fd.h"
 #include "tracefile-array.h"
 
+struct lttcomm_relayd_index;
+
+struct relay_stream_rotation {
+       /*
+        * Indicates if the stream's data and index have been rotated. A
+        * rotation is considered completed when both rotations have occurred.
+        */
+       bool data_rotated;
+       bool index_rotated;
+       /*
+        * Sequence number of the first packet of the new trace chunk to which
+        * the stream is rotating.
+        */
+       uint64_t seq_num;
+       struct lttng_trace_chunk *next_trace_chunk;
+};
+
 /*
  * Represents a stream in the relay
  */
@@ -61,26 +80,23 @@ struct relay_stream {
        struct lttng_index_file *index_file;
 
        char *path_name;
-       /*
-        * prev_path_name is only used for session rotation support.
-        * It is essentially used to work around the fact that index
-        * files are always created from the 'data' connection.
-        *
-        * Hence, it is possible to receive a ROTATE_STREAM command
-        * which affects the stream's path_name before the creation of
-        * an index file. In this situation, the index file of the
-        * 'previous' chunk would be created in the new destination folder.
-        *
-        * It would then be unlinked when the actual index of the new chunk
-        * is created.
-        */
-       char *prev_path_name;
        char *channel_name;
 
        /* On-disk circular buffer of tracefiles. */
        uint64_t tracefile_size;
        uint64_t tracefile_size_current;
+       /* Max number of trace files for this stream. */
        uint64_t tracefile_count;
+       /*
+        * Index of the currently active file for this stream's on-disk
+        * ring buffer.
+        */
+       uint64_t tracefile_current_index;
+       /*
+        * Indicates that the on-disk buffer has wrapped around. Stream
+        * files shall be unlinked before being opened after this has occurred.
+        */
+       bool tracefile_wrapped_around;
 
        /*
         * Position in the tracefile where we have the full index also on disk.
@@ -146,7 +162,8 @@ struct relay_stream {
         */
        bool in_recv_list;
        struct cds_list_head recv_node;
-       bool published; /* Protected by session lock. */
+       /* Protected by session lock. */
+       bool published;
        /*
         * Node of stream within global stream hash table.
         */
@@ -154,27 +171,11 @@ struct relay_stream {
        bool in_stream_ht;              /* is stream in stream hash table. */
        struct rcu_head rcu_node;       /* For call_rcu teardown. */
        /*
-        * When we have written the data and index corresponding to this
-        * seq_num, rotate the tracefile (session rotation). The path_name is
-        * already up-to-date.
-        * This is set to -1ULL when no rotation is pending.
-        *
-        * Always access with stream lock held.
-        */
-       uint64_t rotate_at_seq_num;
-       /*
-        * When rotate_at_seq_num != -1ULL, meaning that a rotation is ongoing,
-        * data_rotated and index_rotated respectively indicate if the stream's
-        * data and index have been rotated. A rotation is considered completed
-        * when both rotations have occurred.
-        */
-       bool data_rotated;
-       bool index_rotated;
-       /*
-        * `trace_chunk` is the trace chunk to which the file currently
-        * being produced (if any) belongs.
+        * The trace chunk to which the file currently being produced (if any)
+        * belongs.
         */
        struct lttng_trace_chunk *trace_chunk;
+       LTTNG_OPTIONAL(struct relay_stream_rotation) ongoing_rotation;
 };
 
 struct relay_stream *stream_create(struct ctf_trace *trace,
@@ -185,8 +186,28 @@ struct relay_stream *stream_create(struct ctf_trace *trace,
 struct relay_stream *stream_get_by_id(uint64_t stream_id);
 bool stream_get(struct relay_stream *stream);
 void stream_put(struct relay_stream *stream);
+int stream_rotate_output_files(struct relay_session *session,
+               struct relay_stream *stream);
+int stream_set_pending_rotation(struct relay_stream *stream,
+               struct lttng_trace_chunk *next_trace_chunk,
+               uint64_t rotation_sequence_number);
 void try_stream_close(struct relay_stream *stream);
 void stream_publish(struct relay_stream *stream);
+int stream_init_packet(struct relay_stream *stream, size_t packet_size,
+               bool *file_rotated);
+int stream_write(struct relay_stream *stream,
+               const struct lttng_buffer_view *packet, size_t padding_len);
+/* Called after the reception of a complete data packet. */
+int stream_update_index(struct relay_stream *stream, uint64_t net_seq_num,
+               bool rotate_index, bool *flushed, uint64_t total_size);
+int stream_complete_packet(struct relay_stream *stream,
+               size_t packet_total_size, uint64_t sequence_number,
+               bool index_flushed);
+/* Index info is in host endianness. */
+int stream_add_index(struct relay_stream *stream,
+               const struct lttcomm_relayd_index *index_info);
+int stream_reset_file(struct relay_stream *stream);
+
 void print_relay_streams(void);
 
 #endif /* _STREAM_H */