src/thread/__wait.c

   1 #include "pthread_impl.h"
   2
   3 void __wait(volatile int *addr, volatile int *waiters, int val, int priv)
   4 {
   5         int spins=100;
   6         if (priv) priv = FUTEX_PRIVATE;
   7         while (spins-- && (!waiters || !*waiters)) {
   8                 if (*addr==val) a_spin();
   9                 else return;
  10         }
  11         if (waiters) a_inc(waiters);
  12         while (*addr==val) {
  13                 __syscall(SYS_futex, addr, FUTEX_WAIT|priv, val, 0) != -ENOSYS
  14                 || __syscall(SYS_futex, addr, FUTEX_WAIT, val, 0);
  15         }
  16         if (waiters) a_dec(waiters);
  17 }