1 #ifndef _LINUX_RING_BUFFER_BACKEND_TYPES_H
2 #define _LINUX_RING_BUFFER_BACKEND_TYPES_H
5 * linux/ringbuffer/backend_types.h
7 * Copyright (C) 2008-2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
9 * Ring buffer backend (types).
11 * Dual LGPL v2.1/GPL v2 license.
15 #include "shm_internal.h"
18 struct lttng_ust_lib_ring_buffer_backend_pages
{
19 unsigned long mmap_offset
; /* offset of the subbuffer in mmap */
20 union v_atomic records_commit
; /* current records committed count */
21 union v_atomic records_unread
; /* records to read */
22 unsigned long data_size
; /* Amount of data to read from subbuf */
23 DECLARE_SHMP(char, p
); /* Backing memory map */
26 struct lttng_ust_lib_ring_buffer_backend_subbuffer
{
27 /* Identifier for subbuf backend pages. Exchanged atomically. */
28 unsigned long id
; /* backend subbuffer identifier */
32 * Forward declaration of frontend-specific channel and ring_buffer.
35 struct lttng_ust_lib_ring_buffer
;
37 struct lttng_ust_lib_ring_buffer_backend_pages_shmp
{
38 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_pages
, shmp
);
41 struct lttng_ust_lib_ring_buffer_backend
{
42 /* Array of ring_buffer_backend_subbuffer for writer */
43 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_subbuffer
, buf_wsb
);
44 /* ring_buffer_backend_subbuffer for reader */
45 struct lttng_ust_lib_ring_buffer_backend_subbuffer buf_rsb
;
47 * Pointer array of backend pages, for whole buffer.
48 * Indexed by ring_buffer_backend_subbuffer identifier (id) index.
50 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_pages_shmp
, array
);
51 DECLARE_SHMP(char, memory_map
); /* memory mapping */
53 DECLARE_SHMP(struct channel
, chan
); /* Associated channel */
54 int cpu
; /* This buffer's cpu. -1 if global. */
55 union v_atomic records_read
; /* Number of records read */
56 unsigned int allocated
:1; /* is buffer allocated ? */
59 struct lttng_ust_lib_ring_buffer_shmp
{
60 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer
, shmp
); /* Channel per-cpu buffers */
63 struct channel_backend
{
64 unsigned long buf_size
; /* Size of the buffer */
65 unsigned long subbuf_size
; /* Sub-buffer size */
66 unsigned int subbuf_size_order
; /* Order of sub-buffer size */
67 unsigned int num_subbuf_order
; /*
68 * Order of number of sub-buffers/buffer
71 unsigned int buf_size_order
; /* Order of buffer size */
72 unsigned int extra_reader_sb
:1; /* has extra reader subbuffer ? */
73 unsigned long num_subbuf
; /* Number of sub-buffers for writer */
74 uint64_t start_tsc
; /* Channel creation TSC value */
75 DECLARE_SHMP(void *, priv_data
);/* Client-specific information */
76 struct lttng_ust_lib_ring_buffer_config config
; /* Ring buffer configuration */
77 char name
[NAME_MAX
]; /* Channel name */
78 struct lttng_ust_lib_ring_buffer_shmp buf
[];
81 #endif /* _LINUX_RING_BUFFER_BACKEND_TYPES_H */