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

[Yong Wang]

Support TCP/UDP checksum offload.

Signed-off-by: Yong Wang <yongwang at 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