[dpdk-stable] patch 'net/bnxt: fix Tx descriptor status implementation' has been queued to stable release 20.11.3

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 20.11.3

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 07/14/21. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://github.com/bluca/dpdk-stable

This queued commit can be viewed at:
https://github.com/bluca/dpdk-stable/commit/2dfab9aad47e5209eb356e11cf937605f645189d

Thanks.

Luca Boccassi

---
>From 2dfab9aad47e5209eb356e11cf937605f645189d Mon Sep 17 00:00:00 2001
From: Lance Richardson <lance.richardson at broadcom.com>
Date: Wed, 16 Jun 2021 13:55:21 -0400
Subject: [PATCH] net/bnxt: fix Tx descriptor status implementation

[ upstream commit ce5c57ac01af038b930d5164df2cb16193e238ec ]

With Tx completion batching, a single transmit completion
can correspond to one or more transmit descriptors, adjust
implementation to account for this.

RTE_ETH_TX_DESC_DONE should be returned for descriptors that
are available for use instead of RTE_ETH_TX_DESC_UNAVAIL.

Fixes: 5735eb241947 ("net/bnxt: support Tx batching")
Fixes: 478ed3bb7b9d ("net/bnxt: support Tx descriptor status")

Signed-off-by: Lance Richardson <lance.richardson at broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde at broadcom.com>
---
 drivers/net/bnxt/bnxt_ethdev.c | 56 +++++++++++++++++++---------------
 1 file changed, 32 insertions(+), 24 deletions(-)

diff --git a/drivers/net/bnxt/bnxt_ethdev.c b/drivers/net/bnxt/bnxt_ethdev.c
index f34e90e8df..2bd3c9eaa5 100644
--- a/drivers/net/bnxt/bnxt_ethdev.c
+++ b/drivers/net/bnxt/bnxt_ethdev.c
@@ -3213,41 +3213,49 @@ static int
 bnxt_tx_descriptor_status_op(void *tx_queue, uint16_t offset)
 {
 	struct bnxt_tx_queue *txq = (struct bnxt_tx_queue *)tx_queue;
-	struct bnxt_tx_ring_info *txr;
-	struct bnxt_cp_ring_info *cpr;
-	struct bnxt_sw_tx_bd *tx_buf;
-	struct tx_pkt_cmpl *txcmp;
-	uint32_t cons, cp_cons;
+	struct bnxt_cp_ring_info *cpr = txq->cp_ring;
+	uint32_t ring_mask, raw_cons, nb_tx_pkts = 0;
+	struct bnxt_ring *cp_ring_struct;
+	struct cmpl_base *cp_desc_ring;
 	int rc;
 
-	if (!txq)
-		return -EINVAL;
-
 	rc = is_bnxt_in_error(txq->bp);
 	if (rc)
 		return rc;
 
-	cpr = txq->cp_ring;
-	txr = txq->tx_ring;
-
 	if (offset >= txq->nb_tx_desc)
 		return -EINVAL;
 
-	cons = RING_CMP(cpr->cp_ring_struct, offset);
-	txcmp = (struct tx_pkt_cmpl *)&cpr->cp_desc_ring[cons];
-	cp_cons = cpr->cp_raw_cons;
-
-	if (cons > cp_cons) {
-		if (CMPL_VALID(txcmp, cpr->valid))
-			return RTE_ETH_TX_DESC_UNAVAIL;
-	} else {
-		if (CMPL_VALID(txcmp, !cpr->valid))
-			return RTE_ETH_TX_DESC_UNAVAIL;
-	}
-	tx_buf = &txr->tx_buf_ring[cons];
-	if (tx_buf->mbuf == NULL)
+	/* Return "desc done" if descriptor is available for use. */
+	if (bnxt_tx_bds_in_hw(txq) <= offset)
 		return RTE_ETH_TX_DESC_DONE;
 
+	raw_cons = cpr->cp_raw_cons;
+	cp_desc_ring = cpr->cp_desc_ring;
+	cp_ring_struct = cpr->cp_ring_struct;
+	ring_mask = cpr->cp_ring_struct->ring_mask;
+
+	/* Check to see if hw has posted a completion for the descriptor. */
+	while (1) {
+		struct tx_cmpl *txcmp;
+		uint32_t cons;
+
+		cons = RING_CMPL(ring_mask, raw_cons);
+		txcmp = (struct tx_cmpl *)&cp_desc_ring[cons];
+
+		if (!CMP_VALID(txcmp, raw_cons, cp_ring_struct))
+			break;
+
+		if (CMP_TYPE(txcmp) == TX_CMPL_TYPE_TX_L2)
+			nb_tx_pkts += rte_le_to_cpu_32(txcmp->opaque);
+
+		if (nb_tx_pkts > offset)
+			return RTE_ETH_TX_DESC_DONE;
+
+		raw_cons = NEXT_RAW_CMP(raw_cons);
+	}
+
+	/* Descriptor is pending transmit, not yet completed by hardware. */
 	return RTE_ETH_TX_DESC_FULL;
 }
 
-- 
2.30.2

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2021-07-12 13:41:41.203927310 +0100
+++ 0089-net-bnxt-fix-Tx-descriptor-status-implementation.patch	2021-07-12 13:41:36.758128194 +0100
@@ -1 +1 @@
-From ce5c57ac01af038b930d5164df2cb16193e238ec Mon Sep 17 00:00:00 2001
+From 2dfab9aad47e5209eb356e11cf937605f645189d Mon Sep 17 00:00:00 2001
@@ -5,0 +6,2 @@
+[ upstream commit ce5c57ac01af038b930d5164df2cb16193e238ec ]
+
@@ -15 +16,0 @@
-Cc: stable at dpdk.org
@@ -24 +25 @@
-index 74ade93b71..4d51a209f9 100644
+index f34e90e8df..2bd3c9eaa5 100644
@@ -27 +28 @@
-@@ -3296,41 +3296,49 @@ static int
+@@ -3213,41 +3213,49 @@ static int
@@ -33 +34 @@
--	struct rte_mbuf **tx_buf;
+-	struct bnxt_sw_tx_bd *tx_buf;
@@ -67 +68 @@
--	if (*tx_buf == NULL)
+-	if (tx_buf->mbuf == NULL)