pfinet/asm/system.h


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#include <cthreads.h>

/* This lock is held when "interrupts" are disabled. */
extern struct mutex global_interrupt_lock;

/* Save the "processor state" in the longword FLAGS. */
/* We define 1 to mean that global_interrupt_lock is held. */

#define save_flags(x) _real_save_flags (&x)
extern inline void 
_real_save_flags (u_long *flagsword)
{
  int locked;
  
  locked = !mutex_try_lock (&global_interrupt_lock);
  if (!locked)
    mutex_unlock (&global_interrupt_lock);
  *flagsword = locked;
}

/* Restore state saved in FLAGS. */
extern inline void
restore_flags (u_long flags)
{
  if (flags)
    mutex_try_lock (&global_interrupt_lock);
  else
    mutex_unlock (&global_interrupt_lock);
}

/* Prevent "interrupts" from happening. */
extern inline void 
cli ()
{
  mutex_try_lock (&global_interrupt_lock);
}

/* Permit "interrupts". */ 
extern inline void
sti ()
{
  mutex_unlock (&global_interrupt_lock);
}