[RFC 2/2] ethdev: queue-based flow aged report

[Thomas Monjalon]

07/04/2022 07:30, Xiaoyu Min:
> When application use queue-based flow management and operate the same
> flow on the same queue, e.g create/destroy/query, API for querying aged
> flows should also with queue id parameter just like other queue-based
> flow APIs.

A verb is missing, I am not sure to understand.

> By this way, PMD can work in more optimized way since resources are
> isolated by queue and needn't synchronize.
> 
> If application do use queue-based flow management but configure port
> without RTE_FLOW_PORT_FLAG_STRICT_QUEUE, which means application operate
> the same flow on different queues, the queue id parameter will
> be ignored.
> 
> Signed-off-by: Xiaoyu Min <jackmin at nvidia.com>
> ---
>  doc/guides/prog_guide/rte_flow.rst |  4 +++
>  lib/ethdev/rte_flow.h              | 44 ++++++++++++++++++++++++++++++
>  lib/ethdev/rte_flow_driver.h       |  7 +++++
>  3 files changed, 55 insertions(+)
> 
> diff --git a/doc/guides/prog_guide/rte_flow.rst b/doc/guides/prog_guide/rte_flow.rst
> index 588914b231..d540152d74 100644
> --- a/doc/guides/prog_guide/rte_flow.rst
> +++ b/doc/guides/prog_guide/rte_flow.rst
> @@ -2963,6 +2963,10 @@ Set ageing timeout configuration to a flow.
>  Event RTE_ETH_EVENT_FLOW_AGED will be reported if
>  timeout passed without any matching on the flow.
>  
> +If queue-based flow rule management is used, when this
> +even is triggered, the ret_param is set to corresponding
> +flow queue.
> +
>  .. _table_rte_flow_action_age:
>  
>  .. table:: AGE
> diff --git a/lib/ethdev/rte_flow.h b/lib/ethdev/rte_flow.h
> index 578dd837f5..9394fb6965 100644
> --- a/lib/ethdev/rte_flow.h
> +++ b/lib/ethdev/rte_flow.h
>   * The flow context and the flow handle will be reported by the
>   * rte_flow_get_aged_flows API.
> + *
> + * If queue-based flow rule management is used and port configured with
> + * flag RTE_FLOW_PORT_FLAG_STRICT_QUEUE, RTE_ETH_EVENT_FLOW_AGED event
> + * is triggered with ret_param set to the corresponding flow queue when
> + * a flow queue detects new aged-out flows.

Are you sure it is a good idea to use ret_param for such data?
ret_param of an event is supposed to be used by the driver
to get a confirmation from the application.

If the application needs extra info of an event,
it is better to do a separate query like rte_flow_get_aged_flows().