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                 if (t->ret > 0 || !t->error_handler)
  20                         continue;
  21                 if (t->ret < 0) {
  22                         t->error_handler(t);
  23                         goto again;
  24                 }
  25                 if (!(t->flags & PRE_EOF_IS_ERROR))
  26                         continue;
  27                 t->ret = -E_PRE_EOF;
  28                 t->error_handler(t);
  29                 goto again;
  30         }
  31 }
  32
  33 static void sched_post_select(struct sched *s)
  34 {
  35         struct task *t, *tmp;
  36
  37         list_for_each_entry_safe(t, tmp, &post_select_list, post_select_node) {
  38                 t->post_select(s, t);
  39                 if (t->ret > 0 || !t->error_handler)
  40                         continue;
  41                 if (t->ret < 0) {
  42                         t->error_handler(t);
  43                         continue;
  44                 }
  45                 if (!(t->flags & POST_EOF_IS_ERROR))
  46                         continue;
  47                 t->ret = -E_POST_EOF;
  48                 t->error_handler(t);
  49         }
  50 }
  51
  52 int sched(struct sched *s)
  53 {
  54
  55         gettimeofday(&s->now, NULL);
  56 again:
  57         FD_ZERO(&s->rfds);
  58         FD_ZERO(&s->wfds);
  59         s->timeout = s->default_timeout;
  60         s->max_fileno = -1;
  61         sched_preselect(s);
  62         s->select_ret = para_select(s->max_fileno + 1, &s->rfds,
  63                 &s->wfds, &s->timeout);
  64         if (s->select_ret < 0)
  65                 return s->select_ret;
  66         gettimeofday(&s->now, NULL);
  67         sched_post_select(s);
  68         if (list_empty(&pre_select_list) && list_empty(&post_select_list))
  69                 return 0;
  70         goto again;
  71 }
  72
  73 void *register_task(struct task *t)
  74 {
  75         PARA_INFO_LOG("registering task %p\n", t);
  76         if (t->pre_select) {
  77                 PARA_DEBUG_LOG("pre_select: %p\n", &t->pre_select);
  78                 if (t->flags & PRE_ADD_TAIL)
  79                         list_add_tail(&t->pre_select_node, &pre_select_list);
  80                 else
  81                         list_add(&t->pre_select_node, &pre_select_list);
  82         }
  83         if (t->post_select) {
  84                 PARA_DEBUG_LOG("post_select: %p\n", &t->pre_select);
  85                 if (t->flags & POST_ADD_TAIL)
  86                         list_add_tail(&t->post_select_node, &post_select_list);
  87                 else
  88                         list_add(&t->post_select_node, &post_select_list);
  89         }
  90         return t;
  91 }
  92
  93 void unregister_task(struct task *t)
  94 {
  95         PARA_INFO_LOG("unregistering task %p\n", t);
  96         if (t->pre_select)
  97                 list_del(&t->pre_select_node);
  98         if (t->post_select)
  99                 list_del(&t->post_select_node);
 100 };
 101
 102 void init_sched(void)
 103 {
 104         INIT_LIST_HEAD(&pre_select_list);
 105         INIT_LIST_HEAD(&post_select_list);
 106 };
 107
 108 void sched_shutdown(void)
 109 {
 110         struct task *t, *tmp;
 111
 112         list_for_each_entry_safe(t, tmp, &pre_select_list, pre_select_node)
 113                 unregister_task(t);
 114         /* remove tasks which do not have a pre_select hook */
 115         list_for_each_entry_safe(t, tmp, &post_select_list, post_select_node)
 116                 unregister_task(t);
 117 };
 118
 119
 120 //char *get_tast_list();