[openib-general] Re: IPoIB completion handler

[Roland Dreier]

    Hal> Why key off bit in wc.wr_id rather than use wc.opcode to
    Hal> determine where the completed operation was a receive or
    Hal> transmit ?

    Hal> Also, when wc.status != success, wr_id cannot be trusted but
    Hal> is still used to determine operation type (receive/transmit)
    Hal> and more importantly the index into transmit/receive
    Hal> ring. Can't the index be determined based on rotating around
    Hal> the rings based on the number of receive or transmit
    Hal> completions "seen" without using the wr_id ? Are there other
    Hal> better ways of doing this ?

As we discussed earlier, the WR ID _is_ valid no matter what the
status is, while the operation type is _not_ valid if the status is
not success.  It's true that we could keep track of the next send and
next receive we expect to complete and just use the WR ID to
distinguish between sends and receives, but it seems like six of one,
half dozen of another to me.

 - Roland