On Sep 25, 2015 11:44 AM, "Jingjing Wu" <jingjing.wu at intel.com> wrote:
>
> In SR-IOV mode a VF sending LFC or PFC would throttle the entire port.
> The workaround is to add a filter to drop pause frames from VFs from
> sending pause frames.
This is a very strange approach - this would silently disable the Tx FC
while a user would think it's enabled. Wouldn't the right approach be to
let the user decide weather to enable this feature or even better - allow
PF to disable this feature in the VF?
>
> Signed-off-by: Jingjing Wu <jingjing.wu at intel.com>
> ---
> drivers/net/i40e/i40e_ethdev.c | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
> diff --git a/drivers/net/i40e/i40e_ethdev.c
b/drivers/net/i40e/i40e_ethdev.c
> index 2dd9fdc..6cc2172 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -382,6 +382,30 @@ static inline void i40e_flex_payload_reg_init(struct
i40e_hw *hw)
> I40E_WRITE_REG(hw, I40E_GLQF_PIT(17), 0x00007440);
> }
>
> +#define I40E_FLOW_CONTROL_ETHERTYPE 0x8808
> +
> +/*
> + * Add a ethertype filter to drop all flow control frames transimited
> + * from VSIs.
> +*/
> +static void
> +i40e_add_tx_flow_control_drop_filter(struct i40e_pf *pf)
> +{
> + struct i40e_hw *hw = I40E_PF_TO_HW(pf);
> + uint16_t flags = I40E_AQC_ADD_CONTROL_PACKET_FLAGS_IGNORE_MAC |
> + I40E_AQC_ADD_CONTROL_PACKET_FLAGS_DROP |
> + I40E_AQC_ADD_CONTROL_PACKET_FLAGS_TX;
> + int ret;
> +
> + ret = i40e_aq_add_rem_control_packet_filter(hw, NULL,
> + I40E_FLOW_CONTROL_ETHERTYPE, flags,
> + pf->main_vsi_seid, 0,
> + TRUE, NULL, NULL);
> + if (ret)
> + PMD_INIT_LOG(ERR, "Failed to add filter to drop flow
control "
> + " frames from VSIs.");
> +}
> +
> static int
> eth_i40e_dev_init(struct rte_eth_dev *dev)
> {
> @@ -584,6 +608,12 @@ eth_i40e_dev_init(struct rte_eth_dev *dev)
>
> /* enable uio intr after callback register */
> rte_intr_enable(&(pci_dev->intr_handle));
> + /*
> + * Add a ethertype filter to drop all flow control frames
transimited
> + * from VSIs. This is used to workaround the issue -- in SR-IOV
mode
> + * where a VF sending LFC or PFC would throttle the entire port.
> + */
> + i40e_add_tx_flow_control_drop_filter(pf);
>
> /* initialize mirror rule list */
> TAILQ_INIT(&pf->mirror_list);
> --
> 2.4.0
>
