On Thu, Aug 31, 2017 at 03:40:13PM +0200, Olivier Matz wrote:
> The selection of Rx/Tx handlers is done at several places,
> group them in one function set_rxtx_funcs().
>
> The update of hw->use_simple_rxtx is also rationalized:
> - initialized to 1 (prefer simple path)
> - in dev configure or rx/tx queue setup, if something prevents from
> using the simple path, change it to 0.
> - in dev start, set the handlers according to hw->use_simple_rxtx.
>
> Cc: sta...@dpdk.org
This patch looks like a refactoring to me, that I don't think it's really
a good idea to back port it to a stable release.
...
> @@ -1534,7 +1554,6 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
> RTE_BUILD_BUG_ON(RTE_PKTMBUF_HEADROOM < sizeof(struct
> virtio_net_hdr_mrg_rxbuf));
>
> eth_dev->dev_ops = &virtio_eth_dev_ops;
> - eth_dev->tx_pkt_burst = &virtio_xmit_pkts;
>
> if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
> if (!hw->virtio_user_dev) {
> @@ -1544,12 +1563,8 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
> }
>
> virtio_set_vtpci_ops(hw);
> - if (hw->use_simple_rxtx) {
> - eth_dev->tx_pkt_burst = virtio_xmit_pkts_simple;
> - eth_dev->rx_pkt_burst = virtio_recv_pkts_vec;
> - } else {
> - rx_func_get(eth_dev);
> - }
> + set_rxtx_funcs(eth_dev);
No need to invoke it here?
> +
> return 0;
> }
>
> @@ -1726,6 +1741,18 @@ virtio_dev_configure(struct rte_eth_dev *dev)
> return -EBUSY;
> }
>
> + hw->use_simple_rxtx = 1;
> +
> +#if defined RTE_ARCH_X86
> + if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE3))
DPDK now requires SSE4.2. You might want to add another patch to remove
this testing.
> + hw->use_simple_rxtx = 0;
> +#elif defined RTE_ARCH_ARM64 || defined CONFIG_RTE_ARCH_ARM
> + if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON))
> + hw->use_simple_rxtx = 0;
> +#endif
> + if (vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF))
> + hw->use_simple_rxtx = 0;
> +
> return 0;
> }
>
> @@ -1802,6 +1829,7 @@ virtio_dev_start(struct rte_eth_dev *dev)
> VIRTQUEUE_DUMP(txvq->vq);
> }
>
> + set_rxtx_funcs(dev);
> hw->started = 1;
>
> /* Initialize Link state */
> diff --git a/drivers/net/virtio/virtio_rxtx.c
> b/drivers/net/virtio/virtio_rxtx.c
> index a32e3229f..c9d97b643 100644
> --- a/drivers/net/virtio/virtio_rxtx.c
> +++ b/drivers/net/virtio/virtio_rxtx.c
> @@ -505,25 +505,14 @@ static void
> virtio_update_rxtx_handler(struct rte_eth_dev *dev,
> const struct rte_eth_txconf *tx_conf)
This function name doesn't quite make sense now after your refactoring.
> {
> - uint8_t use_simple_rxtx = 0;
> struct virtio_hw *hw = dev->data->dev_private;
> + uint8_t use_simple_rxtx = hw->use_simple_rxtx;
>
> -#if defined RTE_ARCH_X86
> - if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_SSE3))
> - use_simple_rxtx = 1;
> -#elif defined RTE_ARCH_ARM64 || defined CONFIG_RTE_ARCH_ARM
> - if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_NEON))
> - use_simple_rxtx = 1;
> -#endif
> - /* Use simple rx/tx func if single segment and no offloads */
> - if (use_simple_rxtx &&
> - (tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) == VIRTIO_SIMPLE_FLAGS &&
> - !vtpci_with_feature(hw, VIRTIO_NET_F_MRG_RXBUF)) {
> - PMD_INIT_LOG(INFO, "Using simple rx/tx path");
> - dev->tx_pkt_burst = virtio_xmit_pkts_simple;
> - dev->rx_pkt_burst = virtio_recv_pkts_vec;
> - hw->use_simple_rxtx = use_simple_rxtx;
> - }
> + /* cannot use simple rxtx funcs with multisegs or offloads */
> + if ((tx_conf->txq_flags & VIRTIO_SIMPLE_FLAGS) != VIRTIO_SIMPLE_FLAGS)
> + use_simple_rxtx = 0;
And that's what left in this function. How about just un-folding it?
--yliu
