atomic_sub_return.h

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#ifndef _PPU_ATOMIC_SUB_RETURN_H_
#define _PPU_ATOMIC_SUB_RETURN_H_

#include <sync_utils.h>
#include <atomic.h>


/**
 * atomic_sub_return - atomically subtract from a counter & return previous.
 * @v: handle to effective address of counter.
 * @a: value to be subtracted.
 *
 * Atomically subtract a value from a counter in system memory.
 * The only restriction is that @v must be word aligned.
 *
 * Returns the previous value from system memory.
 */


static __inline int _atomic_sub_return(int a, atomic_ea_t v)
{
  return _atomic_modify (v, -a);
}

#endif /* _PPU_ATOMIC_SUB_RETURN_H_ */