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"
17 struct lttng_ust_lib_ring_buffer_backend_pages
{
18 unsigned long mmap_offset
; /* offset of the subbuffer in mmap */
19 union v_atomic records_commit
; /* current records committed count */
20 union v_atomic records_unread
; /* records to read */
21 unsigned long data_size
; /* Amount of data to read from subbuf */
22 DECLARE_SHMP(char, p
); /* Backing memory map */
25 struct lttng_ust_lib_ring_buffer_backend_subbuffer
{
26 /* Identifier for subbuf backend pages. Exchanged atomically. */
27 unsigned long id
; /* backend subbuffer identifier */
31 * Forward declaration of frontend-specific channel and ring_buffer.
34 struct lttng_ust_lib_ring_buffer
;
36 struct lttng_ust_lib_ring_buffer_backend_pages_shmp
{
37 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_pages
, shmp
);
40 struct lttng_ust_lib_ring_buffer_backend
{
41 /* Array of ring_buffer_backend_subbuffer for writer */
42 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_subbuffer
, buf_wsb
);
43 /* ring_buffer_backend_subbuffer for reader */
44 struct lttng_ust_lib_ring_buffer_backend_subbuffer buf_rsb
;
46 * Pointer array of backend pages, for whole buffer.
47 * Indexed by ring_buffer_backend_subbuffer identifier (id) index.
49 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer_backend_pages_shmp
, array
);
50 DECLARE_SHMP(char, memory_map
); /* memory mapping */
52 DECLARE_SHMP(struct channel
, chan
); /* Associated channel */
53 int cpu
; /* This buffer's cpu. -1 if global. */
54 union v_atomic records_read
; /* Number of records read */
55 unsigned int allocated
:1; /* Bool: is buffer allocated ? */
58 struct lttng_ust_lib_ring_buffer_shmp
{
59 DECLARE_SHMP(struct lttng_ust_lib_ring_buffer
, shmp
); /* Channel per-cpu buffers */
62 struct channel_backend
{
63 unsigned long buf_size
; /* Size of the buffer */
64 unsigned long subbuf_size
; /* Sub-buffer size */
65 unsigned int subbuf_size_order
; /* Order of sub-buffer size */
66 unsigned int num_subbuf_order
; /*
67 * Order of number of sub-buffers/buffer
70 unsigned int buf_size_order
; /* Order of buffer size */
71 int extra_reader_sb
:1; /* Bool: has extra reader subbuffer */
72 unsigned long num_subbuf
; /* Number of sub-buffers for writer */
73 uint64_t start_tsc
; /* Channel creation TSC value */
74 DECLARE_SHMP(void *, priv_data
);/* Client-specific information */
75 struct lttng_ust_lib_ring_buffer_config config
; /* Ring buffer configuration */
76 char name
[NAME_MAX
]; /* Channel name */
77 struct lttng_ust_lib_ring_buffer_shmp buf
[];
80 #endif /* _LINUX_RING_BUFFER_BACKEND_TYPES_H */