blob: 3f4781c2eed2605d2254ac3db6b9daddae3f3af6 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright(c) 2010-2014 Intel Corporation.
*/
#ifndef _KNI_FIFO_H_
#define _KNI_FIFO_H_
#include <exec-env/rte_kni_common.h>
/* Skip some memory barriers on Linux < 3.14 */
#ifndef smp_load_acquire
#define smp_load_acquire(a) (*(a))
#endif
#ifndef smp_store_release
#define smp_store_release(a, b) *(a) = (b)
#endif
/**
* Adds num elements into the fifo. Return the number actually written
*/
static inline uint32_t
kni_fifo_put(struct rte_kni_fifo *fifo, void **data, uint32_t num)
{
uint32_t i = 0;
uint32_t fifo_write = fifo->write;
uint32_t fifo_read = smp_load_acquire(&fifo->read);
uint32_t new_write = fifo_write;
for (i = 0; i < num; i++) {
new_write = (new_write + 1) & (fifo->len - 1);
if (new_write == fifo_read)
break;
fifo->buffer[fifo_write] = data[i];
fifo_write = new_write;
}
smp_store_release(&fifo->write, fifo_write);
return i;
}
/**
* Get up to num elements from the fifo. Return the number actully read
*/
static inline uint32_t
kni_fifo_get(struct rte_kni_fifo *fifo, void **data, uint32_t num)
{
uint32_t i = 0;
uint32_t new_read = fifo->read;
uint32_t fifo_write = smp_load_acquire(&fifo->write);
for (i = 0; i < num; i++) {
if (new_read == fifo_write)
break;
data[i] = fifo->buffer[new_read];
new_read = (new_read + 1) & (fifo->len - 1);
}
smp_store_release(&fifo->read, new_read);
return i;
}
/**
* Get the num of elements in the fifo
*/
static inline uint32_t
kni_fifo_count(struct rte_kni_fifo *fifo)
{
uint32_t fifo_write = smp_load_acquire(&fifo->write);
uint32_t fifo_read = smp_load_acquire(&fifo->read);
return (fifo->len + fifo_write - fifo_read) & (fifo->len - 1);
}
/**
* Get the num of available elements in the fifo
*/
static inline uint32_t
kni_fifo_free_count(struct rte_kni_fifo *fifo)
{
uint32_t fifo_write = smp_load_acquire(&fifo->write);
uint32_t fifo_read = smp_load_acquire(&fifo->read);
return (fifo_read - fifo_write - 1) & (fifo->len - 1);
}
#endif /* _KNI_FIFO_H_ */
|
