atomic_add_return.h

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#ifndef _SPU_ATOMIC_ADD_RETURN_H_
#define _SPU_ATOMIC_ADD_RETURN_H_

#include <sync_utils.h>
#include <atomic.h>
/**
 * atomic_add_return - atomically add to a counter and return previous value.
 * @v: handle to effective address of counter.
 * @a: value to be added.
 *
 * Atomically add a value to a counter in system memory.
 * The only restriction is that @v must be word aligned.
 *
 * This routine implements the "fetch and add" primitive
 * that is described in "Book I PowerPC User Instruction
 * Set Architecture", but uses MFC lock line reservation
 * operations instead of lwarx/stwcx.
 *
 * Returns the previous value from system memory.
 */
static __inline int _atomic_add_return(int a, atomic_ea_t v)
{
    int ret_val;
    ATOMIC_OP(v, a, 0, ret_val);
    return ret_val;
}


#endif /* _SPU_ATOMIC_ADD_RETURN_H_ */