| 1 | /* |
| 2 | * Copyright (C) 2019 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 3 | * |
| 4 | * SPDX-License-Identifier: LGPL-2.1-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #ifndef LTTNG_TRACE_CHUNK_REGISTRY_H |
| 9 | #define LTTNG_TRACE_CHUNK_REGISTRY_H |
| 10 | |
| 11 | #include <stddef.h> |
| 12 | #include <stdint.h> |
| 13 | #include <stdbool.h> |
| 14 | #include <common/macros.h> |
| 15 | #include <common/trace-chunk.h> |
| 16 | |
| 17 | struct lttng_trace_chunk_registry; |
| 18 | |
| 19 | /* |
| 20 | * Create an lttng_trace_chunk registry. |
| 21 | * |
| 22 | * A trace chunk registry maintains an association between a |
| 23 | * (session_id, chunk_id) tuple and a trace chunk object. The chunk_id can |
| 24 | * be "unset" in the case of an anonymous trace chunk. |
| 25 | * |
| 26 | * Note that a trace chunk registry holds no ownership of its trace |
| 27 | * chunks. Trace chunks are unpublished when their last reference is released. |
| 28 | * See the documentation of lttng_trace_chunk. |
| 29 | * |
| 30 | * Returns a trace chunk registry on success, NULL on error. |
| 31 | * |
| 32 | * Note that a trace chunk registry may only be accessed by an RCU thread. |
| 33 | */ |
| 34 | LTTNG_HIDDEN |
| 35 | struct lttng_trace_chunk_registry *lttng_trace_chunk_registry_create(void); |
| 36 | |
| 37 | /* |
| 38 | * Destroy an lttng trace chunk registry. The registry must be emptied |
| 39 | * (i.e. all references to the trace chunks it contains must be released) before |
| 40 | * it is destroyed. |
| 41 | */ |
| 42 | LTTNG_HIDDEN |
| 43 | void lttng_trace_chunk_registry_destroy( |
| 44 | struct lttng_trace_chunk_registry *registry); |
| 45 | |
| 46 | /* |
| 47 | * Publish a trace chunk for a given session id. |
| 48 | * A reference is acquired on behalf of the caller. |
| 49 | * |
| 50 | * The trace chunk that is returned is the published version of the trace |
| 51 | * chunk. The chunk provided should be discarded on success and it's |
| 52 | * published version used in its place. |
| 53 | * |
| 54 | * See the documentation of lttng_trace_chunk for more information on |
| 55 | * the usage of the various parameters. |
| 56 | * |
| 57 | * Returns an lttng_trace_chunk on success, NULL on error. |
| 58 | */ |
| 59 | LTTNG_HIDDEN |
| 60 | struct lttng_trace_chunk *lttng_trace_chunk_registry_publish_chunk( |
| 61 | struct lttng_trace_chunk_registry *registry, |
| 62 | uint64_t session_id, struct lttng_trace_chunk *chunk); |
| 63 | |
| 64 | /* |
| 65 | * Look-up a trace chunk by session_id and chunk_id. |
| 66 | * A reference is acquired on behalf of the caller. |
| 67 | * |
| 68 | * Returns an lttng_trace_chunk on success, NULL if the chunk does not exist. |
| 69 | */ |
| 70 | LTTNG_HIDDEN |
| 71 | struct lttng_trace_chunk * |
| 72 | lttng_trace_chunk_registry_find_chunk( |
| 73 | const struct lttng_trace_chunk_registry *registry, |
| 74 | uint64_t session_id, uint64_t chunk_id); |
| 75 | |
| 76 | /* |
| 77 | * Query the existence of a trace chunk by session_id and chunk_id. |
| 78 | * |
| 79 | * Returns 0 on success, a negative value on error. |
| 80 | */ |
| 81 | LTTNG_HIDDEN |
| 82 | int lttng_trace_chunk_registry_chunk_exists( |
| 83 | const struct lttng_trace_chunk_registry *registry, |
| 84 | uint64_t session_id, uint64_t chunk_id, bool *chunk_exists); |
| 85 | |
| 86 | /* |
| 87 | * Look-up an anonymous trace chunk by session_id. |
| 88 | * A reference is acquired on behalf of the caller. |
| 89 | * |
| 90 | * Returns an lttng_trace_chunk on success, NULL if the chunk does not exist. |
| 91 | */ |
| 92 | LTTNG_HIDDEN |
| 93 | struct lttng_trace_chunk * |
| 94 | lttng_trace_chunk_registry_find_anonymous_chunk( |
| 95 | const struct lttng_trace_chunk_registry *registry, |
| 96 | uint64_t session_id); |
| 97 | |
| 98 | LTTNG_HIDDEN |
| 99 | unsigned int lttng_trace_chunk_registry_put_each_chunk( |
| 100 | const struct lttng_trace_chunk_registry *registry); |
| 101 | |
| 102 | #endif /* LTTNG_TRACE_CHUNK_REGISTRY_H */ |