[dpdk-dev] [PATCH 1/5] ethdev: add capability to keep flow rules on restart

[Ajit Khaparde]

On Mon, Oct 4, 2021 at 5:52 PM <dkozlyuk at oss.nvidia.com> wrote:
>
> From: Dmitry Kozlyuk <dkozlyuk at nvidia.com>
>
> Currently, it is not specified what happens to the flow rules when
> the device is stopped, possibly reconfigured, then started.
> If flow rules were kept, it could be convenient for application
> developers, because they wouldn't need to save and restore them.
> However, due to the number of flows and possible creation rate it is
> impractical to save all flow rules in DPDK layer. This means that flow
> rules persistence really depends on whether PMD and HW can implement it
> efficiently. It is proposed for PMDs to advertise this capability
> if supported using a new flag.
>
> If the device is being reconfigured in a way that is incompatible with
> existing flow rules, PMD is required to report an error.
> This is mandatory, because flow API does not supply users with
> capabilities, so this is the only way for a user to learn that
> configuration is invalid. For example, if queue count changes and the
> action of a flow rule specifies queues that are going away, the user
> must update or remove the flow rule before removing the queues.
>
> Signed-off-by: Dmitry Kozlyuk <dkozlyuk at nvidia.com>

Acked-by: Ajit Khaparde <ajit.khaparde at broadcom.com>