Re: [dpdk-dev] [PATCH] net/pcap: set queue started and stopped

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 7/18/2018 3:17 PM, Eads, Gage wrote:
> 
> 
>> -----Original Message-----
>> From: Yigit, Ferruh
>> Sent: Wednesday, July 18, 2018 4:14 AM
>> To: Eads, Gage <gage.eads@intel.com>; dev@dpdk.org
>> Subject: Re: [PATCH] net/pcap: set queue started and stopped
>>
>> On 7/9/2018 9:21 PM, Gage Eads wrote:
>>> Set the rx and tx queue state appropriately when the queues or device
>>> are started or stopped.
>>
>> Is there a specific reason to enable these dev_ops, if so can you please
>> document in commit log?
> 
> Yes, the purpose of the patch is to enable the rte_eth_dev_{rx, tx}_queue_{start, stop} functions for the PCAP PMD. I'll update the message in v2.

I guess that part is clear :) I was asking if there is a higher level reason to
enable queue start/stop on these PMDs?
Is there some specific usecase not working for you when these are not enabled?

> 
>>
>>>
>>> Signed-off-by: Gage Eads <gage.eads@intel.com>
>>> ---
>>>  drivers/net/pcap/rte_eth_pcap.c | 42
>>> +++++++++++++++++++++++++++++++++++++++++
>>>  1 file changed, 42 insertions(+)
>>>
>>> diff --git a/drivers/net/pcap/rte_eth_pcap.c
>>> b/drivers/net/pcap/rte_eth_pcap.c index 6bd4a7d79..21e466bcd 100644
>>> --- a/drivers/net/pcap/rte_eth_pcap.c
>>> +++ b/drivers/net/pcap/rte_eth_pcap.c
>>> @@ -430,6 +430,10 @@ eth_dev_start(struct rte_eth_dev *dev)
>>>  				return -1;
>>>  			rx->pcap = tx->pcap;
>>>  		}
>>> +
>>> +		dev->data->tx_queue_state[0] =
>> RTE_ETH_QUEUE_STATE_STARTED;
>>> +		dev->data->rx_queue_state[0] =
>> RTE_ETH_QUEUE_STATE_STARTED;
>>
>> pcap also supports multiple queue, instead of hardcoding the queue 0 it can be
>> possible to iterate through dev->data->nb_rx_queues, dev->data-
>>> nb_tx_queues.
>>
>> And I think it is not good to set this in "internals->single_iface" condition, it is
>> better to do these assignments just above "status_up" after all queues
>> initialized.
>>
>>> +
>>>  		goto status_up;
>>>  	}
>>>
>>> @@ -490,6 +494,8 @@ eth_dev_stop(struct rte_eth_dev *dev)
>>>  		pcap_close(tx->pcap);
>>>  		tx->pcap = NULL;
>>>  		rx->pcap = NULL;
>>> +		dev->data->tx_queue_state[0] =
>> RTE_ETH_QUEUE_STATE_STOPPED;
>>> +		dev->data->rx_queue_state[0] =
>> RTE_ETH_QUEUE_STATE_STOPPED;
>>
>> same here, just above "status_down" is better place and by using
>> dev->data->nb_[r/t]x_queues
> 
> Agreed, I will move the started and stopped assignments as you suggested.
>