RDMA/rxe: Make the tasklet exits the same

Make changes to the three tasklets so that the exit logic from each is the
same. This makes the code easier to understand.

Link: https://lore.kernel.org/r/20220630190425.2251-8-rpearsonhpe@gmail.com
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Author: Bob Pearson

drivers/infiniband/sw/rxe/rxe_comp.c

@@ -562,7 +562,7 @@ int rxe_completer(void *arg)
 	struct sk_buff *skb = NULL;
 	struct rxe_pkt_info *pkt = NULL;
 	enum comp_state state;
-	int ret = 0;
+	int ret;
 
 	if (!rxe_get(qp))
 		return -EAGAIN;
@@ -571,8 +571,7 @@ int rxe_completer(void *arg)
 	    qp->req.state == QP_STATE_RESET) {
 		rxe_drain_resp_pkts(qp, qp->valid &&
 				    qp->req.state == QP_STATE_ERROR);
-		ret = -EAGAIN;
-		goto done;
+		goto exit;
 	}
 
 	if (qp->comp.timeout) {
@@ -582,10 +581,8 @@ int rxe_completer(void *arg)
 		qp->comp.timeout_retry = 0;
 	}
 
-	if (qp->req.need_retry) {
-		ret = -EAGAIN;
-		goto done;
-	}
+	if (qp->req.need_retry)
+		goto exit;
 
 	state = COMPST_GET_ACK;
 
@@ -678,8 +675,7 @@ int rxe_completer(void *arg)
 			    qp->qp_timeout_jiffies)
 				mod_timer(&qp->retrans_timer,
 					  jiffies + qp->qp_timeout_jiffies);
-			ret = -EAGAIN;
-			goto done;
+			goto exit;
 
 		case COMPST_ERROR_RETRY:
 			/* we come here if the retry timer fired and we did
@@ -691,10 +687,8 @@ int rxe_completer(void *arg)
 			 */
 
 			/* there is nothing to retry in this case */
-			if (!wqe || (wqe->state == wqe_state_posted)) {
-				ret = -EAGAIN;
-				goto done;
-			}
+			if (!wqe || (wqe->state == wqe_state_posted))
+				goto exit;
 
 			/* if we've started a retry, don't start another
 			 * retry sequence, unless this is a timeout.
@@ -746,8 +740,7 @@ int rxe_completer(void *arg)
 				mod_timer(&qp->rnr_nak_timer,
 					  jiffies + rnrnak_jiffies(aeth_syn(pkt)
 						& ~AETH_TYPE_MASK));
-				ret = -EAGAIN;
-				goto done;
+				goto exit;
 			} else {
 				rxe_counter_inc(rxe,
 						RXE_CNT_RNR_RETRY_EXCEEDED);
@@ -760,12 +753,20 @@ int rxe_completer(void *arg)
 			WARN_ON_ONCE(wqe->status == IB_WC_SUCCESS);
 			do_complete(qp, wqe);
 			rxe_qp_error(qp);
-			ret = -EAGAIN;
-			goto done;
+			goto exit;
 		}
 	}
 
+	/* A non-zero return value will cause rxe_do_task to
+	 * exit its loop and end the tasklet. A zero return
+	 * will continue looping and return to rxe_completer
+	 */
 done:
+	ret = 0;
+	goto out;
+exit:
+	ret = -EAGAIN;
+out:
 	if (pkt)
 		free_pkt(pkt);
 	rxe_put(qp);

drivers/infiniband/sw/rxe/rxe_req.c

@@ -624,6 +624,7 @@ int rxe_requester(void *arg)
 	u32 payload;
 	int mtu;
 	int opcode;
+	int err;
 	int ret;
 	struct rxe_send_wqe rollback_wqe;
 	u32 rollback_psn;
@@ -634,7 +635,6 @@ int rxe_requester(void *arg)
 	if (!rxe_get(qp))
 		return -EAGAIN;
 
-next_wqe:
 	if (unlikely(!qp->valid || qp->req.state == QP_STATE_ERROR))
 		goto exit;
 
@@ -649,7 +649,7 @@ int rxe_requester(void *arg)
 		goto exit;
 	}
 
-	/* we come here if the retransmot timer has fired
+	/* we come here if the retransmit timer has fired
 	 * or if the rnr timer has fired. If the retransmit
 	 * timer fires while we are processing an RNR NAK wait
 	 * until the rnr timer has fired before starting the
@@ -670,11 +670,11 @@ int rxe_requester(void *arg)
 	}
 
 	if (wqe->mask & WR_LOCAL_OP_MASK) {
-		ret = rxe_do_local_ops(qp, wqe);
-		if (unlikely(ret))
+		err = rxe_do_local_ops(qp, wqe);
+		if (unlikely(err))
 			goto err;
 		else
-			goto next_wqe;
+			goto done;
 	}
 
 	if (unlikely(qp_type(qp) == IB_QPT_RC &&
@@ -723,8 +723,7 @@ int rxe_requester(void *arg)
 			wqe->state = wqe_state_done;
 			wqe->status = IB_WC_SUCCESS;
 			__rxe_do_task(&qp->comp.task);
-			rxe_put(qp);
-			return 0;
+			goto done;
 		}
 		payload = mtu;
 	}
@@ -740,25 +739,29 @@ int rxe_requester(void *arg)
 	if (unlikely(!av)) {
 		pr_err("qp#%d Failed no address vector\n", qp_num(qp));
 		wqe->status = IB_WC_LOC_QP_OP_ERR;
-		goto err_drop_ah;
+		goto err;
 	}
 
 	skb = init_req_packet(qp, av, wqe, opcode, payload, &pkt);
 	if (unlikely(!skb)) {
 		pr_err("qp#%d Failed allocating skb\n", qp_num(qp));
 		wqe->status = IB_WC_LOC_QP_OP_ERR;
-		goto err_drop_ah;
+		if (ah)
+			rxe_put(ah);
+		goto err;
 	}
 
-	ret = finish_packet(qp, av, wqe, &pkt, skb, payload);
-	if (unlikely(ret)) {
+	err = finish_packet(qp, av, wqe, &pkt, skb, payload);
+	if (unlikely(err)) {
 		pr_debug("qp#%d Error during finish packet\n", qp_num(qp));
-		if (ret == -EFAULT)
+		if (err == -EFAULT)
 			wqe->status = IB_WC_LOC_PROT_ERR;
 		else
 			wqe->status = IB_WC_LOC_QP_OP_ERR;
 		kfree_skb(skb);
-		goto err_drop_ah;
+		if (ah)
+			rxe_put(ah);
+		goto err;
 	}
 
 	if (ah)
@@ -773,13 +776,14 @@ int rxe_requester(void *arg)
 	save_state(wqe, qp, &rollback_wqe, &rollback_psn);
 	update_wqe_state(qp, wqe, &pkt);
 	update_wqe_psn(qp, wqe, &pkt, payload);
-	ret = rxe_xmit_packet(qp, &pkt, skb);
-	if (ret) {
+
+	err = rxe_xmit_packet(qp, &pkt, skb);
+	if (err) {
 		qp->need_req_skb = 1;
 
 		rollback_state(wqe, qp, &rollback_wqe, rollback_psn);
 
-		if (ret == -EAGAIN) {
+		if (err == -EAGAIN) {
 			rxe_run_task(&qp->req.task, 1);
 			goto exit;
 		}
@@ -790,16 +794,20 @@ int rxe_requester(void *arg)
 
 	update_state(qp, &pkt);
 
-	goto next_wqe;
-
-err_drop_ah:
-	if (ah)
-		rxe_put(ah);
+	/* A non-zero return value will cause rxe_do_task to
+	 * exit its loop and end the tasklet. A zero return
+	 * will continue looping and return to rxe_requester
+	 */
+done:
+	ret = 0;
+	goto out;
 err:
 	wqe->state = wqe_state_error;
 	__rxe_do_task(&qp->comp.task);
-
 exit:
+	ret = -EAGAIN;
+out:
 	rxe_put(qp);
-	return -EAGAIN;
+
+	return ret;
 }

drivers/infiniband/sw/rxe/rxe_resp.c

@@ -1276,17 +1276,15 @@ int rxe_responder(void *arg)
 	struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
 	enum resp_states state;
 	struct rxe_pkt_info *pkt = NULL;
-	int ret = 0;
+	int ret;
 
 	if (!rxe_get(qp))
 		return -EAGAIN;
 
 	qp->resp.aeth_syndrome = AETH_ACK_UNLIMITED;
 
-	if (!qp->valid) {
-		ret = -EINVAL;
-		goto done;
-	}
+	if (!qp->valid)
+		goto exit;
 
 	switch (qp->resp.state) {
 	case QP_STATE_RESET:
@@ -1466,9 +1464,16 @@ int rxe_responder(void *arg)
 		}
 	}
 
+	/* A non-zero return value will cause rxe_do_task to
+	 * exit its loop and end the tasklet. A zero return
+	 * will continue looping and return to rxe_responder
+	 */
+done:
+	ret = 0;
+	goto out;
 exit:
 	ret = -EAGAIN;
-done:
+out:
 	rxe_put(qp);
 	return ret;
 }