why ibv_wc src_qp is zero

["Liu, Changcheng" <changcheng.liu@xxxxxxxxx>]

Hi all,
   Does anyone know the usage of the src_qp field in struct ibv_wc?

   I’m using RC transport type with only Send Operation on Send Queue.
     On the requester side, when SQ WR is finished, there’s one WCE is on CQ. ibv_wc::src_qp is checked with zero value.
     On the responder side, when RQ WR is finished, there’s one WCE is on CQ. ibv_wc::src_qp is checked with zero value too.
   Why the ibv_wc::src_qp field is zero instead of recording the peer's qp number?

--Thanks
Changcheng