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
|
/* $OpenBSD: synch.h,v 1.8 2021/06/13 21:11:54 kettenis Exp $ */
/*
* Copyright (c) 2017 Martin Pieuchot
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/atomic.h>
#include <sys/time.h>
#include <sys/futex.h>
static inline int
_wake(volatile uint32_t *p, int n)
{
return futex(p, FUTEX_WAKE, n, NULL, NULL);
}
static inline int
_twait(volatile uint32_t *p, int val, clockid_t clockid, const struct timespec *abs)
{
struct timespec rel;
int saved_errno = errno;
int error;
if (abs == NULL) {
error = futex(p, FUTEX_WAIT, val, NULL, NULL);
if (error == -1) {
error = errno;
errno = saved_errno;
}
return error;
}
if (abs->tv_nsec >= 1000000000 || clock_gettime(clockid, &rel))
return EINVAL;
rel.tv_sec = abs->tv_sec - rel.tv_sec;
if ((rel.tv_nsec = abs->tv_nsec - rel.tv_nsec) < 0) {
rel.tv_sec--;
rel.tv_nsec += 1000000000;
}
if (rel.tv_sec < 0)
return ETIMEDOUT;
error = futex(p, FUTEX_WAIT, val, &rel, NULL);
if (error == -1) {
error = errno;
errno = saved_errno;
}
return error;
}
static inline int
_requeue(volatile uint32_t *p, int n, int m, volatile uint32_t *q)
{
return futex(p, FUTEX_REQUEUE, n, (void *)(long)m, q);
}
|
