[ovs-dev] [PATCH] netdev-dpdk: Fix failure to configure flow control at netdev-init.

[Ian Stokes]

On 7/10/2018 2:23 PM, Sugesh Chandran wrote:
> Configuring flow control at ixgbe netdev-init is throwing error in port
> start.
> 
> For eg: without this fix, user cannot configure flow control on ixgbe dpdk
> port as below,
> 
> "
>      ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk \
>          options:dpdk-devargs=0000:05:00.1 options:rx-flow-ctrl=true
> "
> 
> Instead,  it must be configured as two different commands,
> 
> "
>      ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk \
>                 options:dpdk-devargs=0000:05:00.1
>      ovs-vsctl set Interface dpdk0 options:rx-flow-ctrl=true
> "
> 
> The DPDK ixgbe driver is now validating all the 'rte_eth_fc_conf' fields before
> trying to configuring the dpdk ethdev. Hence OVS can no longer set the
> 'dont care' fields to just '0' as before. This commit make sure all the
> 'rte_eth_fc_conf' fields are populated with default values before the dev
> init.
> 

Thanks for the patch Sugesh, I've applied to dpdk_merge and it will be 
part of this weeks pull request.

I assume it should be backported to OVS 2.9 at least, do you know if it 
should go to 2.8/2.7 also?

Ian
> Signed-off-by: Sugesh Chandran <sugesh.chandran at intel.com>
> ---
>   lib/netdev-dpdk.c | 15 +++++++--------
>   1 file changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
> index bb4d60f26..023b80d3e 100644
> --- a/lib/netdev-dpdk.c
> +++ b/lib/netdev-dpdk.c
> @@ -1065,14 +1065,6 @@ dpdk_eth_dev_init(struct netdev_dpdk *dev)
>   
>       mbp_priv = rte_mempool_get_priv(dev->dpdk_mp->mp);
>       dev->buf_size = mbp_priv->mbuf_data_room_size - RTE_PKTMBUF_HEADROOM;
> -
> -    /* Get the Flow control configuration for DPDK-ETH */
> -    diag = rte_eth_dev_flow_ctrl_get(dev->port_id, &dev->fc_conf);
> -    if (diag) {
> -        VLOG_DBG("cannot get flow control parameters on port "DPDK_PORT_ID_FMT
> -                 ", err=%d", dev->port_id, diag);
> -    }
> -
>       return 0;
>   }
>   
> @@ -1773,6 +1765,13 @@ netdev_dpdk_set_config(struct netdev *netdev, const struct smap *args,
>       autoneg = smap_get_bool(args, "flow-ctrl-autoneg", false);
>   
>       fc_mode = fc_mode_set[tx_fc_en][rx_fc_en];
> +    /* Get the Flow control configuration for DPDK-ETH */
> +    err = rte_eth_dev_flow_ctrl_get(dev->port_id, &dev->fc_conf);
> +    if (err) {
> +        VLOG_INFO("cannot get flow control parameters on port "DPDK_PORT_ID_FMT
> +                 ", err=%d", dev->port_id, err);
> +    }
> +
>       if (dev->fc_conf.mode != fc_mode || autoneg != dev->fc_conf.autoneg) {
>           dev->fc_conf.mode = fc_mode;
>           dev->fc_conf.autoneg = autoneg;
>