blob: 1382e0dbc290180a4a3de8d433e9748297d1b51f (
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
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
|
class label_queue
{
queue: array[label];
head, tail: int32;
ensure ()
{
if (queue == null)
{
queue = new array[label] (256);
head = tail = 0;
}
}
push_back (l: label)
{
ensure();
queue[(tail++) & 0xff] = l;
}
pop_head() -> label
{
ensure();
return queue[(head++) & 0xff];
}
is_empty() -> bool
{
return head == tail;
}
};
run_list := new label_queue();
thread_yield()
{
run_list.push_back (this_thread);
goto run_list.pop_head();
@this_thread:
}
thread_fork (child: fn())
{
run_list.push_back (this_thread);
child();
goto run_list.pop_head();
@this_thread:
}
thread_exit()
{
if (!run_list.is_empty())
goto run_list.pop_head();
else
goto process_exit;
}
/*
* Demonstration of cooperative thread system
*/
n_done: int32;
t1 ()
{
thread_fork (fn () { t2 ("t2:1"); });
for (i := 0; i < 3; ++i)
{
print "t1";
if (i % 2 == 0)
thread_yield();
}
print "done: t1, forking some more t2s";
thread_fork (fn() { t2 ("t2:2"); });
thread_fork (fn() { t2 ("t2:3"); });
n_done++;
thread_exit();
}
t2 (name: string)
{
for (i := 0; i < 7; ++i)
{
print name, 12;
if (i % 2 == 0)
thread_yield();
}
print "done:", name;
n_done++;
thread_exit();
}
n_done = 0;
/* Fork thread 1 */
thread_fork (t1);
/* Exit main thread */
thread_exit ();
/* And spin forever if we ever get here (which we shouldn't) */
for (;;)
print "We shouldn't get here";
/* Once the last thread exits, it will go here */
@process_exit:
print n_done, "threads finished";
|
