Re: [dpdk-dev] [RFC PATCH] ethdev: support priority based flow control

[Jerin Jacob <jerinjacobk@gmail.com>]

On Tue, Oct 5, 2021 at 6:32 PM <jerinj@marvell.com> wrote:
>
> From: Jerin Jacob <jerinj@marvell.com>
>
> rte_eth_dev_priority_flow_ctrl_set() based API is not generic as it
> can not support other than VLAN priority mapping to PFC traffic class.
>
> Introducing RTE_FLOW_ACTION_TYPE_PFC_SET_TC rte_flow action to
> set the traffic class as per 802.1Qbb specification. This will enable,
> Traffic class(8bit) to be selected based on any packet field like DSCP.
>
> Also, making it as rte_flow action will enable fine control on
> traffic class selection to a specific queue or VF etc.
>
> Signed-off-by: Jerin Jacob <jerinj@marvell.com>

Ping. If there are no comments on RFC, Planning to send v1 for 22.02.

> ---
>
> Planning to submit the testpmd and cnxk ethdev driver changes after receiving
> the feedback on this.
>
>
>  doc/guides/prog_guide/rte_flow.rst | 24 ++++++++++++++++++++++++
>  lib/ethdev/rte_flow.c              |  1 +
>  lib/ethdev/rte_flow.h              | 27 +++++++++++++++++++++++++++
>  3 files changed, 52 insertions(+)
>
> diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
> index 2b42d5ec8c..e59f8a2902 100644
> --- a/doc/guides/prog_guide/rte_flow.rst
> +++ b/doc/guides/prog_guide/rte_flow.rst
> @@ -2999,6 +2999,30 @@ which is set in the packet meta-data (i.e. struct ``rte_mbuf::sched::color``)
>     | ``meter_color`` | Packet color |
>     +-----------------+--------------+
>
> +Action: ``PFC_SET_TC``
> +^^^^^^^^^^^^^^^^^^^^^^
> +
> +Set traffic class as per PFC (802.1Qbb) specification.
> +
> +This action must be used with any of the following action.
> +
> +- ``RTE_FLOW_ACTION_TYPE_QUEUE``
> +- ``RTE_FLOW_ACTION_TYPE_RSS``
> +- ``RTE_FLOW_ACTION_TYPE_PF``
> +- ``RTE_FLOW_ACTION_TYPE_VF``
> +- ``RTE_FLOW_ACTION_TYPE_PHY_PORT``
> +- ``RTE_FLOW_ACTION_TYPE_PORT_ID``
> +
> +.. _table_rte_flow_action_pfc_set_tc:
> +
> +.. table:: PFC_SET_PRIORITY
> +
> +   +-----------------+-------------------------------------+
> +   | Field           | Value                               |
> +   +=================+=====================================+
> +   | ``tc``          | Traffic class as per PFC (802.1Qbb) |
> +   +-----------------+-------------------------------------+
> +
>  Negative types
>  ~~~~~~~~~~~~~~
>
> diff --git a/lib/ethdev/rte_flow.c b/lib/ethdev/rte_flow.c
> index 8cb7a069c8..75c661159e 100644
> --- a/lib/ethdev/rte_flow.c
> +++ b/lib/ethdev/rte_flow.c
> @@ -189,6 +189,7 @@ static const struct rte_flow_desc_data rte_flow_desc_action[] = {
>          */
>         MK_FLOW_ACTION(INDIRECT, 0),
>         MK_FLOW_ACTION(CONNTRACK, sizeof(struct rte_flow_action_conntrack)),
> +       MK_FLOW_ACTION(PFC_SET_TC, sizeof(struct rte_flow_action_pfc_set_tc)),
>  };
>
>  int
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index 7b1ed7f110..5298418e9e 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
> @@ -2409,6 +2409,13 @@ enum rte_flow_action_type {
>          * See struct rte_flow_action_meter_color.
>          */
>         RTE_FLOW_ACTION_TYPE_METER_COLOR,
> +
> +       /**
> +        * Set traffic class as per PFC (802.1Qbb) specification.
> +        *
> +        * See struct rte_flow_action_pfc_set_tc.
> +        */
> +       RTE_FLOW_ACTION_TYPE_PFC_SET_TC,
>  };
>
>  /**
> @@ -3168,6 +3175,26 @@ struct rte_flow_action_meter_color {
>         enum rte_color color; /**< Packet color. */
>  };
>
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this structure may change without prior notice
> + *
> + * RTE_FLOW_ACTION_TYPE_PFC_SET_TC
> + *
> + * Set traffic class as per PFC (802.1Qbb) specification.
> + *
> + * This action must be used any of the following action.
> + * - RTE_FLOW_ACTION_TYPE_QUEUE,
> + * - RTE_FLOW_ACTION_TYPE_RSS,
> + * - RTE_FLOW_ACTION_TYPE_PF,
> + * - RTE_FLOW_ACTION_TYPE_VF,
> + * - RTE_FLOW_ACTION_TYPE_PHY_PORT,
> + * - RTE_FLOW_ACTION_TYPE_PORT_ID
> + */
> +struct rte_flow_action_pfc_set_tc {
> +       uint8_t tc; /**< Traffic class as per PFC (802.1Qbb) specification */
> +};
> +
>  /**
>   * Field IDs for MODIFY_FIELD action.
>   */
> --
> 2.33.0
>