lunaix-os/kernel/ds/waitq.c

   1 #include <lunaix/ds/waitq.h>
   2 #include <lunaix/process.h>
   3 #include <lunaix/sched.h>
   4 #include <lunaix/spike.h>
   5
   6 void
   7 pwait(waitq_t* queue)
   8 {
   9     assert(current_thread);
  10     // prevent race condition.
  11     cpu_disable_interrupt();
  12
  13     waitq_t* current_wq = &current_thread->waitqueue;
  14     assert(llist_empty(&current_wq->waiters));
  15
  16     llist_append(&queue->waiters, &current_wq->waiters);
  17
  18     block_current_thread();
  19     sched_pass();
  20
  21     // In case of SIGINT-forced awaken
  22     llist_delete(&current_wq->waiters);
  23     cpu_enable_interrupt();
  24 }
  25
  26 void
  27 pwake_one(waitq_t* queue)
  28 {
  29     if (llist_empty(&queue->waiters)) {
  30         return;
  31     }
  32
  33     waitq_t* wq = list_entry(queue->waiters.next, waitq_t, waiters);
  34     struct thread* thread = container_of(wq, struct thread, waitqueue);
  35
  36     assert(thread->state == PS_BLOCKED);
  37     thread->state = PS_READY;
  38     llist_delete(&wq->waiters);
  39 }
  40
  41 void
  42 pwake_all(waitq_t* queue)
  43 {
  44     if (llist_empty(&queue->waiters)) {
  45         return;
  46     }
  47
  48     struct thread* thread;
  49     waitq_t *pos, *n;
  50     llist_for_each(pos, n, &queue->waiters, waiters)
  51     {
  52         thread = container_of(pos, struct thread, waitqueue);
  53
  54         assert(thread->state == PS_BLOCKED);
  55         thread->state = PS_READY;
  56         llist_delete(&pos->waiters);
  57     }
  58 }