Re: [dpdk-dev] [PATCH v5 2/2] ethdev: change queue release callback

["Xueming(Steven) Li" <xuemingl@nvidia.com>]

On Wed, 2021-10-06 at 09:04 +0100, Ferruh Yigit wrote:
> On 10/6/2021 8:55 AM, Xueming(Steven) Li wrote:
> > On Tue, 2021-10-05 at 17:38 +0100, Ferruh Yigit wrote:
> > > On 9/29/2021 2:57 PM, Xueming(Steven) Li wrote:
> > > > On Wed, 2021-09-22 at 12:54 +0000, Xueming(Steven) Li wrote:
> > > > > On Wed, 2021-09-22 at 11:57 +0100, Ferruh Yigit wrote:
> > > > > > > > 
> > > > > > > > <...>
> > > > > > > > 
> > > > > > > > >    void
> > > > > > > > > -i40e_dev_rx_queue_release(void *rxq)
> > > > > > > > > +i40e_dev_rx_queue_release(struct rte_eth_dev *dev, uint16_t qid)
> > > > > > > > > +{
> > > > > > > > > +	i40e_rx_queue_release(dev->data->rx_queues[qid]);
> > > > > > > > > +}
> > > > > > > > > +
> > > > > > > > > +void
> > > > > > > > > +i40e_dev_tx_queue_release(struct rte_eth_dev *dev, uint16_t qid)
> > > > > > > > > +{
> > > > > > > > > +	i40e_tx_queue_release(dev->data->tx_queues[qid]);
> > > > > > > > > +}
> > > > > > > > > +
> > > > > > > > 
> > > > > > > > Is there any specific reason to not update driver but add wrappers for it?
> > > > > > > 
> > > > > > > Some caller don't have queue ID on hand, adding wrapper seems more
> > > > > > > convinient.
> > > > > > > 
> > > > > > 
> > > > > > Convinient for the patch, but not sure convinient for the driver.
> > > > > > 
> > > > > > As mentioned before, not sure about approach to update some driver and add
> > > > > > wrappers for some others.
> > > > > > 
> > > > > > qede, ice and i40e seems not updated, I am for syncronizing with their
> > > > > > maintainers before proceed.
> > > > > > 
> > > > > > > 
> > > > > 
> > > > > For qede, qede_tx_queue_release(txq_obj) is called by
> > > > > qede_alloc_tx_queue_mem(dev, qid), while upper caller
> > > > > qede_tx_queue_setup() doesn't always save txq_obj to dev->data->txqs[].
> > > > > 
> > > > > For ice and i40e, it's similar, ice_tx_queue_release() is used to free
> > > > > txq, but some txq isn't saved into dev, please refer to
> > > > > ice_fdir_setup(), wrapper is needed.
> > > > > 
> > > > > These 3 PMDs create rxq/txq that not saved in dev->data, can't change
> > > > > parameter to dev+qid for such case, that's why wrapper was there.
> > > > > 
> > > > 
> > > > Hi Ferruh,
> > > > 
> > > > No response from qede, ice and i40e. Basically the original queue
> > > > release api is shared by private queues(not registered to ethdev),
> > > > can't access by index, that why a warpper was there. To avoid more
> > > > rebase in last minute for this big patch, do you think we could close
> > > > it?
> > > > 
> > > 
> > > I see the reason and since there is no update from maintainers, to keep
> > > the ball rolling agree to continue with wrappers, those PMDs can send
> > > incremental patches if required.
> > > 
> > > > BTW, from feedback from hns3, I will post a new version to add the
> > > > macro.
> > > > 
> > > 
> > > I have concern about this one, how accessing to the global variable
> > > 'rte_eth_devices' via a macro improves the situation?
> > > 
> > > Can you please make wrappers for hns3 driver too, we can follow it later
> > > with driver maintainer?
> > 
> > hns3 doesn't need a wrapper. The macro isn't related to wrapper, just
> > for the rte_eth_devices access as you suggested:
> > 	&rte_eth_devices[hw->data->port_id]
> > 
> 
> I suggested not to access global 'rte_eth_devices' variable from driver, and v6 has
> a macro in the driver [1] to access the same variable, hiding it behind a macro
> is not changing anything.
> Since your updates adds more access to 'rte_eth_devices' [2], my suggestion was
> do a quick wrapper solution for the driver until it is properly updated.
> 
> [1]
> #define HNS3_DEV(hw) &rte_eth_devices[(hw)->data->port_id]
> 
> [2]
> 	-	hns3_dev_rx_queue_release(rxq[i]);
> 	+	hns3_dev_rx_queue_release(HNS3_DEV(hw), i);
> 

Sorry I misunderstood, v7 posted, please check.

Just curios, what's the proper way to access device by port ID? ethdev
is a local struct, saving it in private data struct seems won't make it
work in secondary process, do you think an API should be there to get
device from port ID?