Commit cd8aaddf authored by Bob Pearson's avatar Bob Pearson Committed by Jason Gunthorpe
Browse files

RDMA/rxe: Remove save/rollback_state in rxe_requester 

Now that req.task and comp.task are merged it is no longer necessary to
call save_state() before calling rxe_xmit_pkt() and rollback_state() if
rxe_xmit_pkt() fails. This was done originally to prevent races between
rxe_completer() and rxe_requester() which now cannot happen.

Link: https://lore.kernel.org/r/20240329145513.35381-8-rpearsonhpe@gmail.com


Signed-off-by: default avatarBob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 67f57892

drivers/infiniband/sw/rxe/rxe_req.c

+2 −38
Original line number Diff line number Diff line
@@ -573,30 +573,6 @@ static void update_wqe_psn(struct rxe_qp *qp, 
		qp->req.psn = (qp->req.psn + 1) & BTH_PSN_MASK;

}



static void save_state(struct rxe_send_wqe *wqe,

		       struct rxe_qp *qp,

		       struct rxe_send_wqe *rollback_wqe,

		       u32 *rollback_psn)

{

	rollback_wqe->state = wqe->state;

	rollback_wqe->first_psn = wqe->first_psn;

	rollback_wqe->last_psn = wqe->last_psn;

	rollback_wqe->dma = wqe->dma;

	*rollback_psn = qp->req.psn;

}



static void rollback_state(struct rxe_send_wqe *wqe,

			   struct rxe_qp *qp,

			   struct rxe_send_wqe *rollback_wqe,

			   u32 rollback_psn)

{

	wqe->state = rollback_wqe->state;

	wqe->first_psn = rollback_wqe->first_psn;

	wqe->last_psn = rollback_wqe->last_psn;

	wqe->dma = rollback_wqe->dma;

	qp->req.psn = rollback_psn;

}



static void update_state(struct rxe_qp *qp, struct rxe_pkt_info *pkt)

{

	qp->req.opcode = pkt->opcode;
@@ -676,8 +652,6 @@ int rxe_requester(struct rxe_qp *qp) 
	int opcode;

	int err;

	int ret;

	struct rxe_send_wqe rollback_wqe;

	u32 rollback_psn;

	struct rxe_queue *q = qp->sq.queue;

	struct rxe_ah *ah;

	struct rxe_av *av;
@@ -799,9 +773,6 @@ int rxe_requester(struct rxe_qp *qp) 
	pkt.mask = rxe_opcode[opcode].mask;

	pkt.wqe = wqe;



	/* save wqe state before we build and send packet */

	save_state(wqe, qp, &rollback_wqe, &rollback_psn);



	av = rxe_get_av(&pkt, &ah);

	if (unlikely(!av)) {

		rxe_dbg_qp(qp, "Failed no address vector\n");
@@ -834,10 +805,6 @@ int rxe_requester(struct rxe_qp *qp) 
	if (ah)

		rxe_put(ah);



	/* update wqe state as though we had sent it */

	update_wqe_state(qp, wqe, &pkt);

	update_wqe_psn(qp, wqe, &pkt, payload);



	err = rxe_xmit_packet(qp, &pkt, skb);

	if (err) {

		if (err != -EAGAIN) {
@@ -845,11 +812,6 @@ int rxe_requester(struct rxe_qp *qp) 
			goto err;

		}



		/* the packet was dropped so reset wqe to the state

		 * before we sent it so we can try to resend

		 */

		rollback_state(wqe, qp, &rollback_wqe, rollback_psn);



		/* force a delay until the dropped packet is freed and

		 * the send queue is drained below the low water mark

		 */
@@ -859,6 +821,8 @@ int rxe_requester(struct rxe_qp *qp) 
		goto exit;

	}



	update_wqe_state(qp, wqe, &pkt);

	update_wqe_psn(qp, wqe, &pkt, payload);

	update_state(qp, &pkt);



	/* A non-zero return value will cause rxe_do_task to