[dpdk-dev] [RFC] lib/ethdev: add dev configured flag

[Ferruh Yigit]

On 7/2/2021 12:08 PM, Andrew Rybchenko wrote:
> @Thomas, @Ferruh, I tend to accept it (with minor style fixes),
> but I need your opinion on it before doing it.
> 

I guess we were relying on the user/application to have correct order up until
now, it can be good to add this into the API. OK to add it for me.

> Thanks,
> Andrew.
> 
> On 6/29/21 5:27 AM, Huisong Li wrote:
>>
>> 在 2021/6/14 23:37, Andrew Rybchenko 写道:
>>> Summary should start from "ethdev: "
>>>
>>> Don't forget to include all maintainers in Cc the next time.
>>> Just use --cc-cmd or --to-cmd options.
>> ok, thanks!
>>>
>>> Adding Thomas.
>>>
>>> On 5/8/21 11:00 AM, Huisong Li wrote:
>>>> Currently, if dev_configure is not invoked or fails to be invoked, users
>>>> can still invoke dev_start successfully. This patch adds a
>>>> "dev_configured"
>>>> flag in "rte_eth_dev_data" to control whether dev_start can be invoked.
>>>
>>> In theory there is an indirect condition. If number of configured Tx
>>> *and* Rx queues is 0, device is not configured.
>>
>> That's true. If the framework doesn't have this check, each driver needs
>> to do this.
>>
>> But it's a common thing, and it's probably more reasonable to put it in
>> the ethdev layer.
>>
>>>
>>> I have no strong opinion on the topic. Extra flag requires
>>> extra housekeeping. Indirect conditions are not always good
>>> and could be a subject to change.
>>>
>>>> Signed-off-by: Huisong Li <lihuisong at huawei.com>
>>>> ---
>>>>   lib/ethdev/rte_ethdev.c      | 11 +++++++++++
>>>>   lib/ethdev/rte_ethdev_core.h |  6 +++++-
>>>>   2 files changed, 16 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
>>>> index a187976..7d74b17 100644
>>>> --- a/lib/ethdev/rte_ethdev.c
>>>> +++ b/lib/ethdev/rte_ethdev.c
>>>> @@ -1604,6 +1604,8 @@ rte_eth_dev_configure(uint16_t port_id,
>>>> uint16_t nb_rx_q, uint16_t nb_tx_q,
>>>>       }
>>>>         rte_ethdev_trace_configure(port_id, nb_rx_q, nb_tx_q,
>>>> dev_conf, 0);
>>>> +    dev->data->dev_configured = 1;
>>>> +
>>>>       return 0;
>>>>   reset_queues:
>>>>       eth_dev_rx_queue_config(dev, 0);
>>>> @@ -1614,6 +1616,8 @@ rte_eth_dev_configure(uint16_t port_id,
>>>> uint16_t nb_rx_q, uint16_t nb_tx_q,
>>>>           dev->data->mtu = old_mtu;
>>>>         rte_ethdev_trace_configure(port_id, nb_rx_q, nb_tx_q,
>>>> dev_conf, ret);
>>>> +    dev->data->dev_configured = 0;
>>>> +

I would move it before trace function.

>>>>       return ret;
>>>>   }
>>>>   @@ -1749,6 +1753,13 @@ rte_eth_dev_start(uint16_t port_id)
>>>>         RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_start, -ENOTSUP);
>>>>   +    if (dev->data->dev_configured == 0) {
>>>> +        RTE_ETHDEV_LOG(INFO,
>>>> +            "Device with port_id=%"PRIu16" is not configured.\n",
>>>> +            port_id);

Should log type be warning/error?

>>>> +        return -EINVAL;
>>>> +    }
>>>> +
>>>>       if (dev->data->dev_started != 0) {
>>>>           RTE_ETHDEV_LOG(INFO,
>>>>               "Device with port_id=%"PRIu16" already started\n",
>>>> diff --git a/lib/ethdev/rte_ethdev_core.h b/lib/ethdev/rte_ethdev_core.h
>>>> index 4679d94..b508769 100644
>>>> --- a/lib/ethdev/rte_ethdev_core.h
>>>> +++ b/lib/ethdev/rte_ethdev_core.h
>>>> @@ -167,7 +167,11 @@ struct rte_eth_dev_data {
>>>>           scattered_rx : 1,  /**< RX of scattered packets is ON(1) /
>>>> OFF(0) */
>>>>           all_multicast : 1, /**< RX all multicast mode ON(1) /
>>>> OFF(0). */
>>>>           dev_started : 1,   /**< Device state: STARTED(1) /
>>>> STOPPED(0). */
>>>> -        lro         : 1;   /**< RX LRO is ON(1) / OFF(0) */
>>>> +        lro         : 1,  /**< RX LRO is ON(1) / OFF(0) */
>>>> +        dev_configured : 1;
>>>> +        /**< Device configuration state:
>>>> +         * CONFIGURED(1) / NOT CONFIGURED(0).
>>>> +         */
>>>>       uint8_t rx_queue_state[RTE_MAX_QUEUES_PER_PORT];
>>>>           /**< Queues state: HAIRPIN(2) / STARTED(1) / STOPPED(0). */
>>>>       uint8_t tx_queue_state[RTE_MAX_QUEUES_PER_PORT];
>>>>
>>>
>>> .
>