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
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/* $OpenBSD: kern_sensors.c,v 1.2 2005/11/10 08:20:20 dlg Exp $ */
/*
* Copyright (c) 2005 David Gwynne <dlg@openbsd.org>
*
* 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/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/kthread.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/sensors.h>
int nsensors = 0;
struct sensors_head sensors = SLIST_HEAD_INITIALIZER(&sensors);
struct sensor_task {
void *arg;
void (*func)(void *);
int period;
time_t nextrun;
volatile int running;
TAILQ_ENTRY(sensor_task) entry;
};
void sensor_task_create(void *);
void sensor_task_thread(void *);
void sensor_task_schedule(struct sensor_task *);
TAILQ_HEAD(, sensor_task) tasklist = TAILQ_HEAD_INITIALIZER(tasklist);
int
sensor_task_register(void *arg, void (*func)(void *), int period)
{
struct sensor_task *st;
st = malloc(sizeof(struct sensor_task), M_DEVBUF, M_NOWAIT);
if (st == NULL)
return (1);
st->arg = arg;
st->func = func;
st->period = period;
st->running = 1;
if (TAILQ_EMPTY(&tasklist))
kthread_create_deferred(sensor_task_create, NULL);
sensor_task_schedule(st);
return (0);
}
void
sensor_task_unregister(void *arg)
{
struct sensor_task *st, *nst;
nst = TAILQ_FIRST(&tasklist);
while ((st = nst) != NULL) {
nst = TAILQ_NEXT(st, entry);
if (st->arg == arg) {
st->running = 0;
return;
}
}
}
void
sensor_task_create(void *arg)
{
if (kthread_create(sensor_task_thread, NULL, NULL, "sensors") != 0)
panic("sensors kthread");
}
void
sensor_task_thread(void *arg)
{
struct sensor_task *st, *nst;
time_t now;
while (!TAILQ_EMPTY(&tasklist)) {
nst = TAILQ_FIRST(&tasklist);
while (nst->nextrun > (now = time_uptime))
tsleep(&tasklist, PWAIT, "timeout",
(nst->nextrun - now) * hz);
while ((st = nst) != NULL) {
nst = TAILQ_NEXT(st, entry);
if (st->nextrun > now)
break;
/* take it out while we work on it */
TAILQ_REMOVE(&tasklist, st, entry);
if (!st->running) {
free(st, M_DEVBUF);
continue;
}
/* run the task */
st->func(st->arg);
/* stick it back in the tasklist */
sensor_task_schedule(st);
}
}
kthread_exit(0);
}
void
sensor_task_schedule(struct sensor_task *st)
{
struct sensor_task *cst, *nst;
st->nextrun = time_uptime + st->period;
nst = TAILQ_FIRST(&tasklist);
while ((cst = nst) != NULL) {
nst = TAILQ_NEXT(cst, entry);
if (cst->nextrun > st->nextrun) {
TAILQ_INSERT_BEFORE(cst, st, entry);
return;
}
}
/* must be an empty list, or at the end of the list */
TAILQ_INSERT_TAIL(&tasklist, st, entry);
}
|
