Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 13b18c86 authored by Ralph Campbell's avatar Ralph Campbell Committed by Roland Dreier
Browse files

IB/ipath: Fix RDMA reads 



The PSN used to generate the request following a RDMA read was
incorrect and some state booking wasn't maintained correctly.  This
patch fixes that.

Signed-off-by: default avatarRalph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: default avatarBryan O'Sullivan <bryan.osullivan@qlogic.com>
parent 3f168d2b

drivers/infiniband/hw/ipath/ipath_rc.c

+32 −27
Original line number Diff line number Diff line
@@ -241,10 +241,7 @@ int ipath_make_rc_req(struct ipath_qp *qp, 
		 * original work request since we may need to resend

		 * it.

		 */

		qp->s_sge.sge = wqe->sg_list[0];

		qp->s_sge.sg_list = wqe->sg_list + 1;

		qp->s_sge.num_sge = wqe->wr.num_sge;

		qp->s_len = len = wqe->length;

		len = wqe->length;

		ss = &qp->s_sge;

		bth2 = 0;

		switch (wqe->wr.opcode) {
@@ -368,14 +365,23 @@ int ipath_make_rc_req(struct ipath_qp *qp, 
		default:

			goto done;

		}

		qp->s_sge.sge = wqe->sg_list[0];

		qp->s_sge.sg_list = wqe->sg_list + 1;

		qp->s_sge.num_sge = wqe->wr.num_sge;

		qp->s_len = wqe->length;

		if (newreq) {

			qp->s_tail++;

			if (qp->s_tail >= qp->s_size)

				qp->s_tail = 0;

		}

		bth2 |= qp->s_psn++ & IPATH_PSN_MASK;

		bth2 |= qp->s_psn & IPATH_PSN_MASK;

		if (wqe->wr.opcode == IB_WR_RDMA_READ)

			qp->s_psn = wqe->lpsn + 1;

		else {

			qp->s_psn++;

			if ((int)(qp->s_psn - qp->s_next_psn) > 0)

				qp->s_next_psn = qp->s_psn;

		}

		/*

		 * Put the QP on the pending list so lost ACKs will cause

		 * a retry.  More than one request can be pending so the
@@ -690,13 +696,6 @@ void ipath_restart_rc(struct ipath_qp *qp, u32 psn, struct ib_wc *wc) 
	struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last);

	struct ipath_ibdev *dev;



	/*

	 * If there are no requests pending, we are done.

	 */

	if (ipath_cmp24(psn, qp->s_next_psn) >= 0 ||

	    qp->s_last == qp->s_tail)

		goto done;



	if (qp->s_retry == 0) {

		wc->wr_id = wqe->wr.wr_id;

		wc->status = IB_WC_RETRY_EXC_ERR;
@@ -731,8 +730,6 @@ void ipath_restart_rc(struct ipath_qp *qp, u32 psn, struct ib_wc *wc) 
		dev->n_rc_resends += (int)qp->s_psn - (int)psn;



	reset_psn(qp, psn);



done:

	tasklet_hi_schedule(&qp->s_task);



bail:
@@ -765,6 +762,7 @@ static int do_rc_ack(struct ipath_qp *qp, u32 aeth, u32 psn, int opcode) 
	struct ib_wc wc;

	struct ipath_swqe *wqe;

	int ret = 0;

	u32 ack_psn;



	/*

	 * Remove the QP from the timeout queue (or RNR timeout queue).
@@ -777,26 +775,26 @@ static int do_rc_ack(struct ipath_qp *qp, u32 aeth, u32 psn, int opcode) 
		list_del_init(&qp->timerwait);

	spin_unlock(&dev->pending_lock);



	/* Nothing is pending to ACK/NAK. */

	if (unlikely(qp->s_last == qp->s_tail))

		goto bail;



	/*

	 * Note that NAKs implicitly ACK outstanding SEND and RDMA write

	 * requests and implicitly NAK RDMA read and atomic requests issued

	 * before the NAK'ed request.  The MSN won't include the NAK'ed

	 * request but will include an ACK'ed request(s).

	 */

	ack_psn = psn;

	if (aeth >> 29)

		ack_psn--;

	wqe = get_swqe_ptr(qp, qp->s_last);



	/* Nothing is pending to ACK/NAK. */

	if (qp->s_last == qp->s_tail)

		goto bail;



	/*

	 * The MSN might be for a later WQE than the PSN indicates so

	 * only complete WQEs that the PSN finishes.

	 */

	while (ipath_cmp24(psn, wqe->lpsn) >= 0) {

		/* If we are ACKing a WQE, the MSN should be >= the SSN. */

		if (ipath_cmp24(aeth, wqe->ssn) < 0)

			break;

	while (ipath_cmp24(ack_psn, wqe->lpsn) >= 0) {

		/*

		 * If this request is a RDMA read or atomic, and the ACK is

		 * for a later operation, this ACK NAKs the RDMA read or
@@ -807,7 +805,8 @@ static int do_rc_ack(struct ipath_qp *qp, u32 aeth, u32 psn, int opcode) 
		 * is sent but before the response is received.

		 */

		if ((wqe->wr.opcode == IB_WR_RDMA_READ &&

		     opcode != OP(RDMA_READ_RESPONSE_LAST)) ||

		     (opcode != OP(RDMA_READ_RESPONSE_LAST) ||

		       ipath_cmp24(ack_psn, wqe->lpsn) != 0)) ||

		    ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||

		      wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) &&

		     (opcode != OP(ATOMIC_ACKNOWLEDGE) ||
@@ -825,6 +824,10 @@ static int do_rc_ack(struct ipath_qp *qp, u32 aeth, u32 psn, int opcode) 
			 */

			goto bail;

		}

		if (wqe->wr.opcode == IB_WR_RDMA_READ ||

		    wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||

		    wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)

			tasklet_hi_schedule(&qp->s_task);

		/* Post a send completion queue entry if requested. */

		if (!test_bit(IPATH_S_SIGNAL_REQ_WR, &qp->s_flags) ||

		    (wqe->wr.send_flags & IB_SEND_SIGNALED)) {
@@ -1055,6 +1058,7 @@ static inline void ipath_rc_rcv_resp(struct ipath_ibdev *dev, 
		/* no AETH, no ACK */

		if (unlikely(ipath_cmp24(psn, qp->s_last_psn + 1))) {

			dev->n_rdma_seq++;

			if (qp->s_last != qp->s_tail)

				ipath_restart_rc(qp, qp->s_last_psn + 1, &wc);

			goto ack_done;

		}
@@ -1091,6 +1095,7 @@ static inline void ipath_rc_rcv_resp(struct ipath_ibdev *dev, 
		/* ACKs READ req. */

		if (unlikely(ipath_cmp24(psn, qp->s_last_psn + 1))) {

			dev->n_rdma_seq++;

			if (qp->s_last != qp->s_tail)

				ipath_restart_rc(qp, qp->s_last_psn + 1, &wc);

			goto ack_done;

		}