* signal that state. There are two user-visible tracing_map
* variables, 'hits' and 'drops', which are updated by this function.
* Every time an element is either successfully inserted or retrieved,
* signal that state. There are two user-visible tracing_map
* variables, 'hits' and 'drops', which are updated by this function.
* Every time an element is either successfully inserted or retrieved,
* fails, the 'drops' value is incremented.
*
* This is a lock-free tracing map insertion function implementing a
* fails, the 'drops' value is incremented.
*
* This is a lock-free tracing map insertion function implementing a
* tracing_map_elt. This is a lock-free lookup; see
* tracing_map_insert() for details on tracing_map and how it works.
* Every time an element is retrieved, the 'hits' value is
* tracing_map_elt. This is a lock-free lookup; see
* tracing_map_insert() for details on tracing_map and how it works.
* Every time an element is retrieved, the 'hits' value is
* 'drops' value is never updated by this function.
*
* Return: the tracing_map_elt pointer val associated with the key.
* 'drops' value is never updated by this function.
*
* Return: the tracing_map_elt pointer val associated with the key.