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     cpu_enable_interrupt();
  22 }
  23
  24 void
  25 pwake_one(waitq_t* queue)
  26 {
  27     if (llist_empty(&queue->waiters)) {
  28         return;
  29     }
  30
  31     waitq_t* wq = list_entry(queue->waiters.next, waitq_t, waiters);
  32     struct thread* thread = container_of(wq, struct thread, waitqueue);
  33
  34     assert(thread->state == PS_BLOCKED);
  35     thread->state = PS_READY;
  36     llist_delete(&wq->waiters);
  37 }
  38
  39 void
  40 pwake_all(waitq_t* queue)
  41 {
  42     if (llist_empty(&queue->waiters)) {
  43         return;
  44     }
  45
  46     struct thread* thread;
  47     waitq_t *pos, *n;
  48     llist_for_each(pos, n, &queue->waiters, waiters)
  49     {
  50         thread = container_of(pos, struct thread, waitqueue);
  51
  52         assert(thread->state == PS_BLOCKED);
  53         thread->state = PS_READY;
  54         llist_delete(&pos->waiters);
  55     }
  56 }