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
153
154
155
156
|
/*
*
* Portions of this code was derived from the file kern_fork.c and as such
* is subject to the copyrights below.
*
* Copyright (c) 1982, 1986, 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
* (c) UNIX System Laboratories, Inc.
* All or some portions of this file are derived from material licensed
* to the University of California by American Telephone and Telegraph
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
* the permission of UNIX System Laboratories, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Copyright (c) 1996 Douglas Santry
*
* This code is subject to the beer copyright. If I chance to meet you in a
* bar and this code helped you in some way, you owe me a beer. Only
* in Germany will I accept domestic beer. This code may or may not work
* and I certainly make no claims as to its fitness for *any* purpose.
*
* $Id: kern_threads.c,v 1.13 1999/01/28 17:31:59 dillon Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sysproto.h>
/*
* Low level support for sleep/wakeup paradigm
* If a timeout is specified:
* returns 0 if wakeup
* returns EAGAIN if timed out
* returns EINVAL if error
*
* If a timeout is not specified:
*
* returns time waiting in ticks.
*/
int
thr_sleep(struct proc *p, struct thr_sleep_args *uap) {
int sleepstart;
struct timespec ts;
struct timeval atv;
int error, timo;
timo = 0;
if (uap->timeout != 0) {
/*
* Get timespec struct
*/
if ((error = copyin(uap->timeout, &ts, sizeof(ts))) != 0) {
p->p_wakeup = 0;
return error;
}
if (ts.tv_nsec < 0 || ts.tv_nsec >= 1000000000) {
p->p_wakeup = 0;
return (EINVAL);
}
TIMESPEC_TO_TIMEVAL(&atv, &ts);
if (itimerfix(&atv)) {
p->p_wakeup = 0;
return (EINVAL);
}
timo = tvtohz(&atv);
}
p->p_retval[0] = 0;
if (p->p_wakeup == 0) {
sleepstart = ticks;
p->p_flag |= P_SINTR;
error = tsleep(p, PRIBIO, "thrslp", timo);
p->p_flag &= ~P_SINTR;
if (error == EWOULDBLOCK) {
p->p_wakeup = 0;
p->p_retval[0] = EAGAIN;
return 0;
}
if (uap->timeout == 0)
p->p_retval[0] = ticks - sleepstart;
}
p->p_wakeup = 0;
return (0);
}
int
thr_wakeup(struct proc *p, struct thr_wakeup_args *uap) {
struct proc *pSlave = p->p_leader;
while(pSlave && (pSlave->p_pid != uap->pid))
pSlave = pSlave->p_peers;
if(pSlave == 0) {
p->p_retval[0] = ESRCH;
return(0);
}
pSlave->p_wakeup++;
if((pSlave->p_stat == SSLEEP) && (pSlave->p_wchan == pSlave)) {
wakeup(pSlave);
return(0);
}
p->p_retval[0] = EAGAIN;
return 0;
}
/*
* General purpose yield system call
*/
int
yield(struct proc *p, struct yield_args *uap) {
int s;
p->p_retval[0] = 0;
s = splhigh();
p->p_priority = MAXPRI;
setrunqueue(p);
p->p_stats->p_ru.ru_nvcsw++;
mi_switch();
splx(s);
return(0);
}
|
