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#include "pthread_impl.h"
static int vmlock[2];
void __vm_lock(int inc)
{
for (;;) {
int v = vmlock[0];
if (inc*v < 0) __wait(vmlock, vmlock+1, v, 1);
else if (a_cas(vmlock, v, v+inc)==v) break;
}
}
void __vm_unlock(void)
{
int inc = vmlock[0]>0 ? -1 : 1;
if (a_fetch_add(vmlock, inc)==-inc && vmlock[1])
__wake(vmlock, -1, 1);
}
weak_alias(__vm_lock, __vm_lock_impl);
weak_alias(__vm_unlock, __vm_unlock_impl);
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