[dpdk-dev] [PATCH v3 2/4] vmxnet3: add tx l4 cksum offload

[Yong Wang <yongwang@vmware.com>]

Support TCP/UDP checksum offload.

Signed-off-by: Yong Wang <yongwang@vmware.com>
---
 doc/guides/rel_notes/release_2_3.rst |  3 +++
 drivers/net/vmxnet3/vmxnet3_rxtx.c   | 39 +++++++++++++++++++++++++++---------
 2 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/doc/guides/rel_notes/release_2_3.rst b/doc/guides/rel_notes/release_2_3.rst
index a23c8ac..58205fe 100644
--- a/doc/guides/rel_notes/release_2_3.rst
+++ b/doc/guides/rel_notes/release_2_3.rst
@@ -20,6 +20,9 @@ Drivers
   Tx data ring has been shown to improve small pkt forwarding performance
   on vSphere environment.
 
+* **vmxnet3: add tx l4 cksum offload.**
+
+  Support TCP/UDP checksum offload.
 
 Libraries
 ~~~~~~~~~
diff --git a/drivers/net/vmxnet3/vmxnet3_rxtx.c b/drivers/net/vmxnet3/vmxnet3_rxtx.c
index 2202d31..08e6115 100644
--- a/drivers/net/vmxnet3/vmxnet3_rxtx.c
+++ b/drivers/net/vmxnet3/vmxnet3_rxtx.c
@@ -332,6 +332,8 @@ vmxnet3_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 	uint16_t nb_tx;
 	vmxnet3_tx_queue_t *txq = tx_queue;
 	struct vmxnet3_hw *hw = txq->hw;
+	Vmxnet3_TxQueueCtrl *txq_ctrl = &txq->shared->ctrl;
+	uint32_t deferred = rte_le_to_cpu_32(txq_ctrl->txNumDeferred);
 
 	if (unlikely(txq->stopped)) {
 		PMD_TX_LOG(DEBUG, "Tx queue is stopped.");
@@ -413,21 +415,40 @@ vmxnet3_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 			gdesc->txd.tci = txm->vlan_tci;
 		}
 
-		/* TODO: Add transmit checksum offload here */
+		if (txm->ol_flags & PKT_TX_L4_MASK) {
+			gdesc->txd.om = VMXNET3_OM_CSUM;
+			gdesc->txd.hlen = txm->l2_len + txm->l3_len;
+
+			switch (txm->ol_flags & PKT_TX_L4_MASK) {
+			case PKT_TX_TCP_CKSUM:
+				gdesc->txd.msscof = gdesc->txd.hlen + offsetof(struct tcp_hdr, cksum);
+				break;
+			case PKT_TX_UDP_CKSUM:
+				gdesc->txd.msscof = gdesc->txd.hlen + offsetof(struct udp_hdr, dgram_cksum);
+				break;
+			default:
+				PMD_TX_LOG(WARNING, "requested cksum offload not supported %#llx",
+					   txm->ol_flags & PKT_TX_L4_MASK);
+				abort();
+			}
+		} else {
+			gdesc->txd.hlen = 0;
+			gdesc->txd.om = VMXNET3_OM_NONE;
+			gdesc->txd.msscof = 0;
+		}
+
+		txq_ctrl->txNumDeferred = rte_cpu_to_le_32(++deferred);
 
 		/* flip the GEN bit on the SOP */
 		rte_compiler_barrier();
 		gdesc->dword[2] ^= VMXNET3_TXD_GEN;
-
-		txq->shared->ctrl.txNumDeferred++;
 		nb_tx++;
 	}
 
-	PMD_TX_LOG(DEBUG, "vmxnet3 txThreshold: %u", txq->shared->ctrl.txThreshold);
-
-	if (txq->shared->ctrl.txNumDeferred >= txq->shared->ctrl.txThreshold) {
+	PMD_TX_LOG(DEBUG, "vmxnet3 txThreshold: %u", rte_le_to_cpu_32(txq_ctrl->txThreshold));
 
-		txq->shared->ctrl.txNumDeferred = 0;
+	if (deferred >= rte_le_to_cpu_32(txq_ctrl->txThreshold)) {
+		txq_ctrl->txNumDeferred = 0;
 		/* Notify vSwitch that packets are available. */
 		VMXNET3_WRITE_BAR0_REG(hw, (VMXNET3_REG_TXPROD + txq->queue_id * VMXNET3_REG_ALIGN),
 				       txq->cmd_ring.next2fill);
@@ -728,8 +749,8 @@ vmxnet3_dev_tx_queue_setup(struct rte_eth_dev *dev,
 	PMD_INIT_FUNC_TRACE();
 
 	if ((tx_conf->txq_flags & ETH_TXQ_FLAGS_NOXSUMS) !=
-	    ETH_TXQ_FLAGS_NOXSUMS) {
-		PMD_INIT_LOG(ERR, "TX no support for checksum offload yet");
+	    ETH_TXQ_FLAGS_NOXSUMSCTP) {
+		PMD_INIT_LOG(ERR, "SCTP checksum offload not supported");
 		return -EINVAL;
 	}
 
-- 
1.9.1