src/thread/vmlock.c

   1 #include "pthread_impl.h"
   2
   3 static volatile int vmlock[2];
   4
   5 void __vm_wait()
   6 {
   7         int tmp;
   8         while ((tmp=vmlock[0]))
   9                 __wait(vmlock, vmlock+1, tmp, 1);
  10 }
  11
  12 void __vm_lock()
  13 {
  14         a_inc(vmlock);
  15 }
  16
  17 void __vm_unlock()
  18 {
  19         if (a_fetch_add(vmlock, -1)==1 && vmlock[1])
  20                 __wake(vmlock, -1, 1);
  21 }