Re: [PATCH net-next] ethtool: ice: Support for RSS settings to GTP from ethtool

On Wed, 11 Oct 2023 14:25:55 +0900 takeru hayasaka wrote:

quoted

Regarding the patch - you are only adding flow types, not a new field
(which are defined as RXH_*). If we want to hash on an extra field,
I think we need to specify that field as well?  

I've been really struggling with this...
When I read the Intel ICE documentation, it suggests that in RSS, TEID
can be an additional input.
However, I couldn't think of a reason not to include TEID when
enabling RSS for GTP cases.

https://www.intel.com/content/www/us/en/content-details/617015/intel-ethernet-controller-e810-dynamic-device-personalization-ddp-technology-guide.html
(cf. Table 8. Patterns and Input Sets for iavf RSS)

However, for Flow Director, it's clear that you'd want to include the
TEID field. But since I found that someone from Intel has already
configured it to use TEID with Flow Director, I thought maybe we don't
need to add the TEID parameter for now.

https://patchwork.ozlabs.org/project/intel-wired-lan/cover/20210126065206.137422-1-haiyue.wang@intel.com/

If we want to include something other than TEID (e.g., QFI) in Flow
Director, I think it would be better to prepare a new field.

I think we should expose TEID as a field. It's easier to understand 
the API if fields are all listed, and not implied by the flow hash.