9356dd0c4d14be11fb1284eae7227a8489acf907
[paraslash.git] / sched.c
1 #include <sys/time.h>
2 #include "para.h"
3 #include "ipc.h"
4 #include "fd.h"
5 #include "list.h"
6 #include "sched.h"
7 #include "string.h"
8 #include "error.h"
9
10 struct list_head pre_select_list;
11 struct list_head post_select_list;
12
13 static void sched_preselect(struct sched *s)
14 {
15         struct task *t, *tmp;
16 again:
17         list_for_each_entry_safe(t, tmp, &pre_select_list, pre_select_node) {
18                 t->pre_select(s, t);
19 //              PARA_INFO_LOG("%s \n", t->status);
20                 if (t->ret > 0)
21                         continue;
22                 if (!t->event_handler)
23                         continue;
24                 t->event_handler(t);
25                 goto again;
26         }
27 }
28
29 static void sched_post_select(struct sched *s)
30 {
31         struct task *t, *tmp;
32
33         list_for_each_entry_safe(t, tmp, &post_select_list, post_select_node) {
34                 t->post_select(s, t);
35 //              PARA_INFO_LOG("%s: %d\n", t->status, t->ret);
36                 if (t->ret > 0 || !t->event_handler)
37                         continue;
38                 t->event_handler(t);
39         }
40 }
41
42 int sched(struct sched *s)
43 {
44
45         gettimeofday(&s->now, NULL);
46 again:
47         FD_ZERO(&s->rfds);
48         FD_ZERO(&s->wfds);
49         s->timeout = s->default_timeout;
50         s->max_fileno = -1;
51         sched_preselect(s);
52         s->select_ret = para_select(s->max_fileno + 1, &s->rfds,
53                 &s->wfds, &s->timeout);
54         if (s->select_ret < 0)
55                 return s->select_ret;
56         gettimeofday(&s->now, NULL);
57         sched_post_select(s);
58         if (list_empty(&pre_select_list) && list_empty(&post_select_list))
59                 return 0;
60         goto again;
61 }
62
63 void *register_task(struct task *t)
64 {
65         PARA_INFO_LOG("registering %s (%p)\n", t->status, t);
66         if (t->pre_select) {
67                 PARA_DEBUG_LOG("pre_select: %p\n", &t->pre_select);
68                 if (t->flags & PRE_ADD_TAIL)
69                         list_add_tail(&t->pre_select_node, &pre_select_list);
70                 else
71                         list_add(&t->pre_select_node, &pre_select_list);
72         }
73         if (t->post_select) {
74                 PARA_DEBUG_LOG("post_select: %p\n", &t->pre_select);
75                 if (t->flags & POST_ADD_TAIL)
76                         list_add_tail(&t->post_select_node, &post_select_list);
77                 else
78                         list_add(&t->post_select_node, &post_select_list);
79         }
80         return t;
81 }
82
83 void unregister_task(struct task *t)
84 {
85         PARA_INFO_LOG("unregistering %s (%p)\n", t->status, t);
86         if (t->pre_select)
87                 list_del(&t->pre_select_node);
88         if (t->post_select)
89                 list_del(&t->post_select_node);
90 };
91
92 void init_sched(void)
93 {
94         INIT_LIST_HEAD(&pre_select_list);
95         INIT_LIST_HEAD(&post_select_list);
96 };
97
98 void sched_shutdown(void)
99 {
100         struct task *t, *tmp;
101
102         list_for_each_entry_safe(t, tmp, &pre_select_list, pre_select_node)
103                 unregister_task(t);
104         /* remove tasks which do not have a pre_select hook */
105         list_for_each_entry_safe(t, tmp, &post_select_list, post_select_node)
106                 unregister_task(t);
107 };
108
109
110 //char *get_tast_list();