[PATCH v7 8/8] net/gve: add support for Rx/Tx

[Ferruh Yigit]

On 10/24/2022 6:04 AM, Guo, Junfeng wrote:
> 
> 
>> -----Original Message-----
>> From: Ferruh Yigit <ferruh.yigit at amd.com>
>> Sent: Friday, October 21, 2022 17:52
>> To: Guo, Junfeng <junfeng.guo at intel.com>; Zhang, Qi Z
>> <qi.z.zhang at intel.com>; Wu, Jingjing <jingjing.wu at intel.com>;
>> ferruh.yigit at xilinx.com; Xing, Beilei <beilei.xing at intel.com>
>> Cc: dev at dpdk.org; Li, Xiaoyun <xiaoyun.li at intel.com>;
>> awogbemila at google.com; Richardson, Bruce
>> <bruce.richardson at intel.com>; hemant.agrawal at nxp.com;
>> stephen at networkplumber.org; Xia, Chenbo <chenbo.xia at intel.com>;
>> Zhang, Helin <helin.zhang at intel.com>
>> Subject: Re: [PATCH v7 8/8] net/gve: add support for Rx/Tx
>>
>> On 10/21/2022 10:19 AM, Junfeng Guo wrote:
>>
>>>
>>> Add Rx/Tx of GQI_QPL queue format and GQI_RDA queue format.
>>>
>>> Signed-off-by: Xiaoyun Li <xiaoyun.li at intel.com>
>>> Signed-off-by: Junfeng Guo <junfeng.guo at intel.com>
>>
>> <...>
>>
>>> +
>>> +static inline void
>>> +gve_tx_clean_swr_qpl(struct gve_tx_queue *txq)
>>> +{
>>> +       uint32_t start = txq->sw_ntc;
>>> +       uint32_t ntc, nb_clean;
>>> +
>>> +       ntc = txq->sw_tail;
>>> +
>>> +       if (ntc == start)
>>> +               return;
>>> +
>>> +       /* if wrap around, free twice. */
>>> +       if (ntc < start) {
>>> +               nb_clean = txq->nb_tx_desc - start;
>>> +               if (nb_clean > GVE_TX_MAX_FREE_SZ)
>>> +                       nb_clean = GVE_TX_MAX_FREE_SZ;
>>> +               gve_free_bulk_mbuf(&txq->sw_ring[start], nb_clean);
>>> +
>>> +               txq->sw_nb_free += nb_clean;
>>> +               start += nb_clean;
>>> +               if (start == txq->nb_tx_desc)
>>> +                       start = 0;
>>> +               txq->sw_ntc = start;
>>> +       }
>>> +
>>> +       if (ntc > start) {
>>> +               nb_clean = ntc - start;
>>> +               if (nb_clean > GVE_TX_MAX_FREE_SZ)
>>> +                       nb_clean = GVE_TX_MAX_FREE_SZ;
>>> +               gve_free_bulk_mbuf(&txq->sw_ring[start], nb_clean);
>>> +               txq->sw_nb_free += nb_clean;
>>> +               start += nb_clean;
>>> +               txq->sw_ntc = start;
>>> +       }
>>> +}
>>
>> [copy/paste from previous version]
>>
>> may be can drop the 'if' block, since "ntc == start" and "ntc < start"
>> cases already covered.
> 
> Yes, this 'if' block is dropped in v7 as suggested. Thanks!
> 

This is v7 and please check above code which has the mentioned 'if' 
block exist, do you mean in coming v8?

>>
>> <...>
>>
>>> +uint16_t
>>> +gve_tx_burst(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t
>> nb_pkts)
>>> +{
>>> +       struct gve_tx_queue *txq = tx_queue;
>>> +
>>> +       if (txq->is_gqi_qpl)
>>> +               return gve_tx_burst_qpl(tx_queue, tx_pkts, nb_pkts);
>>> +
>>> +       return gve_tx_burst_ra(tx_queue, tx_pkts, nb_pkts);
>>> +}
>>> +
>>
>> [copy/paste from previous version]
>>
>> Can there be mix of queue types?
>> If only one queue type is supported in specific config, perhaps burst
>> function can be set during configuration, to prevent if check on datapath.
>>
>> This is optimization and can be done later, it doesn't have to be in the
>> set.
> 
> The exact queue type can be fetched from the backend via adminq
> in priv->queue_format. So there won't be mix of the queue types.
> Currently, only GQI_QPL and GQI_RDA queue format are supported
> in PMD. Also, only GQI_QPL queue format is in use on GCP since
> GQI_RDA hasn't been released in production.
> This part code will be optimized/refactored later when involving
> the queue type DQO_RDA. Thanks!
>