Re: [PATCH v2] ethdev: clarify device queue state after start and stop

[Thomas Monjalon <thomas@monjalon.net>]

13/10/2023 17:57, Ferruh Yigit:
> Drivers start/stop device queues on port start/stop, but not all drivers
> update queue state accordingly.
> 
> This becomes more visible if a specific queue stopped explicitly and
> port stopped/started later, in this case although all queues are
> started, the state of that specific queue is stopped and it is
> misleading.
> 
> Misrepresentation of queue state became a defect with commit [1] that
> does forwarding decision based on queue state and commit [2] that gets
> up to date queue state from ethdev/device before forwarding.
> 
> [1]
> commit 3c4426db54fc ("app/testpmd: do not poll stopped queues")
> 
> [2]
> commit 5028f207a4fa ("app/testpmd: fix secondary process packet forwarding")
> 
> This patch documents that status of all queues of a device should be
> `RTE_ETH_QUEUE_STATE_STOPPED` after port stop and their status should
> be`RTE_ETH_QUEUE_STATE_STARTED` after port start.

It is so basic that it may look stupid :)
Yes we still have to enforce such basic things, thank you for this work.

> +REGISTER_TEST_COMMAND(ethdev_api, test_ethdev_api);

Maybe add a comment here to explain it is not part of basic suites,
waiting for all drivers being compliant.

> + * All device queues (except form deferred start queues) status should be
> + * `RTE_ETH_QUEUE_STATE_STARTED` after start.
> + *
>   * On success, all basic functions exported by the Ethernet API (link status,
>   * receive/transmit, and so on) can be invoked.
>   *
> @@ -2828,6 +2831,8 @@ int rte_eth_dev_start(uint16_t port_id);
>   * Stop an Ethernet device. The device can be restarted with a call to
>   * rte_eth_dev_start()
>   *
> + * All device queues status should be `RTE_ETH_QUEUE_STATE_STOPPED` after stop.
> + *

Acked-by: Thomas Monjalon <thomas@monjalon.net>