Re: [PATCH rdma-rc 2/5] IB/rxe: Fix handling of erroneous WR

[Leon Romanovsky <leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>]

[-- Attachment #1: Type: text/plain, Size: 2287 bytes --]

On Tue, Dec 13, 2016 at 08:03:03AM +0100, Bart Van Assche wrote:
> On 11/16/2016 09:39 AM, Leon Romanovsky wrote:
> > @@ -745,13 +746,17 @@ int rxe_requester(void *arg)
> >  	wqe->status = IB_WC_LOC_PROT_ERR;
> >  	wqe->state = wqe_state_error;
> >
> > -complete:
> > -	if (qp_type(qp) != IB_QPT_RC) {
> > -		while (rxe_completer(qp) == 0)
> > -			;
> > -	}
> > -
> > -	return 0;
> > +	/*
> > +	 * IBA Spec. Section 10.7.3.1 SIGNALED COMPLETIONS
> > +	 * ---------8<---------8<-------------
> > +	 * ...Note that if a completion error occurs, a Work Completion
> > +	 * will always be generated, even if the signaling
> > +	 * indicator requests an Unsignaled Completion.
> > +	 * ---------8<---------8<-------------
> > +	 */
> > +	wqe->wr.send_flags |= IB_SEND_SIGNALED;
> > +	__rxe_do_task(&qp->comp.task);
> > +	return -EAGAIN;
>
> Hello Leon and Yonatan,
>
> Sorry for the late reply but I think setting IB_SEND_SIGNALED for WQE's
> reporting a completion error is wrong.

I'm not clear about it. I didn't find in spec what to do with IB_SEND_SIGNALED
flag in case of error.

According to spec:
	"C10-91: The CI shall generate a CQE when a Work Request
	completed under any of the following conditions:
	• The Work Request completed in error"


> I noticed this because this change
> conflicts with Doug's rxe branch on github. Have you considered to apply
> the following (untested) patch instead of setting the IB_SEND_SIGNALED
> flag?
>
> --- a/drivers/infiniband/sw/rxe/rxe_comp.c
> +++ b/drivers/infiniband/sw/rxe/rxe_comp.c
> @@ -418,7 +418,7 @@ static void do_complete(struct rxe_qp *qp, struct rxe_send_w
> qe *wqe)
>
>         if ((qp->sq_sig_type == IB_SIGNAL_ALL_WR) ||
>             (wqe->wr.send_flags & IB_SEND_SIGNALED) ||
> -           (qp->req.state == QP_STATE_ERROR)) {
> +           wqe->status != IB_WC_SUCCESS) {
>                 make_send_cqe(qp, wqe, &cqe);
>                 advance_consumer(qp->sq.queue);
>                 rxe_cq_post(qp->scq, &cqe, 0);
>
> Bart.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
> the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]