Re: [PATCH net-next v4 7/7] net: devmem: allow binding on rx queues with same DMA devices

[Dragos Tatulea]

On Wed, Aug 20, 2025 at 06:16:09PM -0700, Jakub Kicinski wrote:
> On Wed, 20 Aug 2025 20:11:58 +0300 Dragos Tatulea wrote:
> > +static struct device *netdev_nl_get_dma_dev(struct net_device *netdev,
> > +					    unsigned long *rxq_bitmap,
> > +					    struct netlink_ext_ack *extack)
> 
> break after type if it's long and multi line:
> 
> static struct device *
> netdev_nl_get_dma_dev(struct net_device *netdev, unsigned long *rxq_bitmap,
> 		      struct netlink_ext_ack *extack)
>
Will fix. Hope to remember for next times as well.

> > +{
> > +	struct device *dma_dev = NULL;
> > +	u32 rxq_idx, prev_rxq_idx;
> > +
> > +	for_each_set_bit(rxq_idx, rxq_bitmap, netdev->real_num_rx_queues) {
> > +		struct device *rxq_dma_dev;
> > +
> > +		rxq_dma_dev = netdev_queue_get_dma_dev(netdev, rxq_idx);
> > +		/* Multi-PF netdev queues can belong to different DMA devoces.
> 
> typo: devoces
> 
Thanks!

> > +		 * Block this case.
> > +		 */
> > +		if (dma_dev && rxq_dma_dev != dma_dev) {
> > +			NL_SET_ERR_MSG_FMT(extack, "Queue %u has a different dma device than queue %u",
> 
> s/dma/DMA/
> I think we may want to bubble up the Multi-PF thing from the comment to
> the user. This could be quite confusing to people. How about:
> 
> 	"DMA device mismatch between queue %u and %u (multi-PF device?)"
Sounds good. Do we still need the comment? A similar remark is done in
the commit message as well.

Thanks,
Dragos