• Michael S. Tsirkin's avatar
    IB: Return qp pointer as part of ib_wc · 062dbb69
    Michael S. Tsirkin authored
    struct ib_wc currently only includes the local QP number: this matches
    the IB spec, but seems mostly useless. The following patch replaces
    this with the pointer to qp itself, and updates all low level drivers
    and all users.
    
    This has the following advantages:
    - Ability to get a per-qp context through wc->qp->qp_context
    - Existing drivers already have the qp pointer ready in poll cq, so
      this change actually saves a tiny bit (extra memory read) on data path
      (for ehca it would actually be expensive to find the QP pointer when
      polling a CQ, but ehca does not support SRQ so we can leave wc->qp as
      NULL for ehca)
    - Users that need the QP number can still get it through wc->qp->qp_num
    
    Use case:
    
    In IPoIB connected mode code, I have a common CQ shared by multiple
    QPs.  To track connection usage, I need a way to get at some per-QP
    context upon the completion, and I would like to avoid allocating
    context object per work request just to stick a QP pointer into it.
    With this code, I can just use wc->qp->qp_context.
    Signed-off-by: default avatarMichael S. Tsirkin <mst@mellanox.co.il>
    Signed-off-by: default avatarRoland Dreier <rolandd@cisco.com>
    062dbb69
ipath_qp.c 24.8 KB