Re: [dpdk-dev] [PATCH V2] ethdev: add dev configured flag

[Huisong Li <lihuisong@huawei.com>]

在 2021/7/6 16:36, Andrew Rybchenko 写道:
> @David, could you take a look at the ABI breakage warnings for
> the patch. May we ignore it since ABI looks backward
> compatible? Or should be marked as a minor change ABI
> which is backward compatible with DPDK_21?
>
> On 7/6/21 7:10 AM, Huisong Li wrote:
>> Currently, if dev_configure is not called or fails to be called, users
>> can still call dev_start successfully. So it is necessary to have a flag
>> which indicates whether the device is configured, to control whether
>> dev_start can be called and eliminate dependency on user invocation order.
>>
>> The flag stored in "struct rte_eth_dev_data" is more reasonable than
>>   "enum rte_eth_dev_state". "enum rte_eth_dev_state" is private to the
>> primary and secondary processes, and can be independently controlled.
>> However, the secondary process does not make resource allocations and
>> does not call dev_configure(). These are done by the primary process
>> and can be obtained or used by the secondary process. So this patch
>> adds a "dev_configured" flag in "rte_eth_dev_data", like "dev_started".
>>
>> Signed-off-by: Huisong Li <lihuisong@huawei.com>
> Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
>
>> ---
>> v1 -> v2:
>>    - adjusting the description of patch.
>>
>> ---
>>   lib/ethdev/rte_ethdev.c      | 16 ++++++++++++++++
>>   lib/ethdev/rte_ethdev_core.h |  6 +++++-
>>   2 files changed, 21 insertions(+), 1 deletion(-)
>>
>> diff --git a/lib/ethdev/rte_ethdev.c b/lib/ethdev/rte_ethdev.c
>> index c607eab..6540432 100644
>> --- a/lib/ethdev/rte_ethdev.c
>> +++ b/lib/ethdev/rte_ethdev.c
>> @@ -1356,6 +1356,13 @@ rte_eth_dev_configure(uint16_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
>>   		return -EBUSY;
>>   	}
>>   
>> +	/*
>> +	 * Ensure that "dev_configured" is always 0 each time prepare to do
>> +	 * dev_configure() to avoid any non-anticipated behaviour.
>> +	 * And set to 1 when dev_configure() is executed successfully.
>> +	 */
>> +	dev->data->dev_configured = 0;
>> +
>>   	 /* Store original config, as rollback required on failure */
>>   	memcpy(&orig_conf, &dev->data->dev_conf, sizeof(dev->data->dev_conf));
>>   
>> @@ -1606,6 +1613,8 @@ 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;
>> +
> I think it should be inserted before the trace, since tracing
> is intentionally put close to return without any empty lines
> in between.
All right. Do I need to send a patch V3?
>>   	return 0;
>>   reset_queues:
>>   	eth_dev_rx_queue_config(dev, 0);
>> @@ -1751,6 +1760,13 @@ 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);
>> +		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..edf96de 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;
>> +		/**< Indicates whether the device is configured.
>> +		 *   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];
>>
> .