[PATCH v3 07/33] net/ena: restructure the llq policy setting process

[Ferruh Yigit]

On 3/6/2024 12:24 PM, shaibran at amazon.com wrote:
> From: Shai Brandes <shaibran at amazon.com>
> 
> The driver will set the size of the LLQ header size according to the
> recommendation from the device.
> Replaced `enable_llq` and `large_llq_hdr` devargs with
> a new devarg `llq_policy` that accepts the following values:
> 0 - Disable LLQ.
>     Use with extreme caution as it leads to a huge performance
>     degradation on AWS instances from 6th generation onwards.
> 1 - Accept device recommended LLQ policy (Default).
>     Device can recommend normal or large LLQ policy.
> 2 - Enforce normal LLQ policy.
> 3 - Enforce large LLQ policy.
>     Required for packets with header that exceed 96 bytes on
>     AWS instances prior to 5th generation.
> 

We had similar discussion before, although dev_args is not part of the
ABI, it is an user interface, and changes in the devargs will impact
users directly.

What would you think to either keep backward compatilibity in the
devargs (like not remove old one but add new one), or do this change in
24.11 release?