src/bin/lttng-relayd/sessiond-trace-chunks.hpp

   1 /*
   2  * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: GPL-2.0-only
   5  *
   6  */
   7
   8 #ifndef SESSIOND_TRACE_CHUNK_REGISTRY_H
   9 #define SESSIOND_TRACE_CHUNK_REGISTRY_H
  10
  11 #include <common/trace-chunk.hpp>
  12 #include <common/uuid.hpp>
  13
  14 #include <stdint.h>
  15
  16 /*
  17  * A session trace chunk registry allows the relay daemon to share trace chunks
  18  * used by different "relay sessions" when they were created for the same
  19  * user-visible session daemon session. Tracing multiple domains (e.g. ust and
  20  * kernel) results in per-domain relay sessions being created.
  21  *
  22  * Sharing trace chunks, and their output directory more specifically, is
  23  * essential to properly implement session rotations. The sharing of output
  24  * directory handles allows directory renames to be performed once and without
  25  * races that would stem from from multiple renames.
  26  */
  27 struct sessiond_trace_chunk_registry;
  28
  29 struct sessiond_trace_chunk_registry *sessiond_trace_chunk_registry_create();
  30
  31 void sessiond_trace_chunk_registry_destroy(struct sessiond_trace_chunk_registry *sessiond_registry);
  32
  33 int sessiond_trace_chunk_registry_session_created(
  34         struct sessiond_trace_chunk_registry *sessiond_registry, const lttng_uuid& sessiond_uuid);
  35
  36 int sessiond_trace_chunk_registry_session_destroyed(
  37         struct sessiond_trace_chunk_registry *sessiond_registry, const lttng_uuid& sessiond_uuid);
  38
  39 struct lttng_trace_chunk *
  40 sessiond_trace_chunk_registry_publish_chunk(struct sessiond_trace_chunk_registry *sessiond_registry,
  41                                             const lttng_uuid& sessiond_uuid,
  42                                             uint64_t session_id,
  43                                             struct lttng_trace_chunk *chunk);
  44
  45 struct lttng_trace_chunk *sessiond_trace_chunk_registry_get_anonymous_chunk(
  46         struct sessiond_trace_chunk_registry *sessiond_registry,
  47         const lttng_uuid& sessiond_uuid,
  48         uint64_t session_id);
  49
  50 struct lttng_trace_chunk *
  51 sessiond_trace_chunk_registry_get_chunk(struct sessiond_trace_chunk_registry *sessiond_registry,
  52                                         const lttng_uuid& sessiond_uuid,
  53                                         uint64_t session_id,
  54                                         uint64_t chunk_id);
  55
  56 int sessiond_trace_chunk_registry_chunk_exists(
  57         struct sessiond_trace_chunk_registry *sessiond_registry,
  58         const lttng_uuid& sessiond_uuid,
  59         uint64_t session_id,
  60         uint64_t chunk_id,
  61         bool *chunk_exists);
  62
  63 #endif /* SESSIOND_TRACE_CHUNK_REGISTRY_H */