[dpdk-dev] [PATCH v5 8/9] net/virtio: add in-order Rx/Tx into selection

[Marvin Liu <yong.liu@intel.com>]

After IN_ORDER Rx/Tx paths added, need to update Rx/Tx path selection
logic.

Rx path select logic: If IN_ORDER and merge-able are enabled will select
IN_ORDER Rx path. If IN_ORDER is enabled, Rx offload and merge-able are
disabled will select simple Rx path. Otherwise will select normal Rx
path.

Tx path select logic: If IN_ORDER is enabled will select IN_ORDER Tx
path. Otherwise will select default Tx path.

Signed-off-by: Marvin Liu <yong.liu@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/doc/guides/nics/virtio.rst b/doc/guides/nics/virtio.rst
index 46e292c4d..7c099fb7c 100644
--- a/doc/guides/nics/virtio.rst
+++ b/doc/guides/nics/virtio.rst
@@ -201,7 +201,7 @@ The packet transmission flow is:
 Virtio PMD Rx/Tx Callbacks
 --------------------------
 
-Virtio driver has 3 Rx callbacks and 2 Tx callbacks.
+Virtio driver has 4 Rx callbacks and 3 Tx callbacks.
 
 Rx callbacks:
 
@@ -215,6 +215,9 @@ Rx callbacks:
    Vector version without mergeable Rx buffer support, also fixes the available
    ring indexes and uses vector instructions to optimize performance.
 
+#. ``virtio_recv_mergeable_pkts_inorder``:
+   In-order version with mergeable Rx buffer support.
+
 Tx callbacks:
 
 #. ``virtio_xmit_pkts``:
@@ -223,6 +226,8 @@ Tx callbacks:
 #. ``virtio_xmit_pkts_simple``:
    Vector version fixes the available ring indexes to optimize performance.
 
+#. ``virtio_xmit_pkts_inorder``:
+   In-order version.
 
 By default, the non-vector callbacks are used:
 
@@ -254,6 +259,12 @@ Example of using the vector version of the virtio poll mode driver in
 
    testpmd -l 0-2 -n 4 -- -i --tx-offloads=0x0 --rxq=1 --txq=1 --nb-cores=1
 
+In-order callbacks only work on simulated virtio user vdev.
+
+*   For Rx: If mergeable Rx buffers is enabled and in-order is enabled then
+    ``virtio_xmit_pkts_inorder`` is used.
+
+*   For Tx: If in-order is enabled then ``virtio_xmit_pkts_inorder`` is used.
 
 Interrupt mode
 --------------
diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index df50a571a..df7981ddb 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1320,6 +1320,11 @@ set_rxtx_funcs(struct rte_eth_dev *eth_dev)
 		PMD_INIT_LOG(INFO, "virtio: using simple Rx path on port %u",
 			eth_dev->data->port_id);
 		eth_dev->rx_pkt_burst = virtio_recv_pkts_vec;
+	} else if (hw->use_inorder_rx) {
+		PMD_INIT_LOG(INFO,
+			"virtio: using inorder mergeable buffer Rx path on port %u",
+			eth_dev->data->port_id);
+		eth_dev->rx_pkt_burst = &virtio_recv_mergeable_pkts_inorder;
 	} else if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
 		PMD_INIT_LOG(INFO,
 			"virtio: using mergeable buffer Rx path on port %u",
@@ -1335,6 +1340,10 @@ set_rxtx_funcs(struct rte_eth_dev *eth_dev)
 		PMD_INIT_LOG(INFO, "virtio: using simple Tx path on port %u",
 			eth_dev->data->port_id);
 		eth_dev->tx_pkt_burst = virtio_xmit_pkts_simple;
+	} else if (hw->use_inorder_tx) {
+		PMD_INIT_LOG(INFO, "virtio: using inorder Tx path on port %u",
+			eth_dev->data->port_id);
+		eth_dev->tx_pkt_burst = virtio_xmit_pkts_inorder;
 	} else {
 		PMD_INIT_LOG(INFO, "virtio: using standard Tx path on port %u",
 			eth_dev->data->port_id);
@@ -1874,20 +1883,27 @@ virtio_dev_configure(struct rte_eth_dev *dev)
 	hw->use_simple_rx = 1;
 	hw->use_simple_tx = 1;
 
+	if (vtpci_with_feature(hw, VIRTIO_F_IN_ORDER)) {
+		/* Simple Tx not compatible with in-order ring */
+		hw->use_inorder_tx = 1;
+		hw->use_simple_tx = 0;
+		if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
+			hw->use_inorder_rx = 1;
+			hw->use_simple_rx = 0;
+		} else {
+			hw->use_inorder_rx = 0;
+			if (rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
+					   DEV_RX_OFFLOAD_TCP_CKSUM))
+				hw->use_simple_rx = 0;
+		}
+	}
+
 #if defined RTE_ARCH_ARM64 || defined RTE_ARCH_ARM
 	if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON)) {
 		hw->use_simple_rx = 0;
 		hw->use_simple_tx = 0;
 	}
 #endif
-	if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
-		hw->use_simple_rx = 0;
-		hw->use_simple_tx = 0;
-	}
-
-	if (rx_offloads & (DEV_RX_OFFLOAD_UDP_CKSUM |
-			   DEV_RX_OFFLOAD_TCP_CKSUM))
-		hw->use_simple_rx = 0;
 
 	return 0;
 }
-- 
2.17.0