Hi Aleksandr,
Thanks again for your review.
I’ve updated the documentation and commit message in v2 to address your
feedback.
Appreciate your time!
On 9/3/25 3:35 PM, Loktionov, Aleksandr wrote:
*From:*mohammad heib <[email protected]>
*Sent:* Wednesday, September 3, 2025 12:01 PM
*To:* Loktionov, Aleksandr <[email protected]>; intel-wired-
[email protected]
*Cc:* [email protected]; [email protected];
[email protected]; [email protected]; Keller, Jacob E
<[email protected]>; Nguyen, Anthony L
<[email protected]>; Kitszel, Przemyslaw
<[email protected]>
*Subject:* Re: [PATCH net-next,2/2] i40e: support generic devlink param
"max_mac_per_vf"
Hello Aleksandr,
Thank you for your review.
On 9/3/25 12:07 PM, Loktionov, Aleksandr wrote:
-----Original Message-----
From:[email protected] <mailto:[email protected]> <[email protected]>
<mailto:[email protected]>
Sent: Wednesday, September 3, 2025 9:58 AM
To:[email protected]
<mailto:[email protected]>
Cc:[email protected]
<mailto:[email protected]>;[email protected]
<mailto:[email protected]>;
[email protected] <mailto:[email protected]>;[email protected]
<mailto:[email protected]>; Keller, Jacob E
<[email protected]> <mailto:[email protected]>;
Loktionov, Aleksandr
<[email protected]> <mailto:[email protected]>;
Nguyen, Anthony L
<[email protected]> <mailto:[email protected]>;
Kitszel, Przemyslaw
<[email protected]> <mailto:[email protected]>; Mohammad
Heib<[email protected]> <mailto:[email protected]>
Subject: [PATCH net-next,2/2] i40e: support generic devlink param
"max_mac_per_vf"
From: Mohammad Heib<[email protected]> <mailto:[email protected]>
Add support for the new generic devlink runtime parameter
"max_mac_per_vf", which controls the maximum number of MAC addresses a
trusted VF can use.
Good day Mohammad,
Thanks for working on this and for the clear explanation in the commit
message.
I have a couple of questions and thoughts:
1) Scope of the parameter
The name max_mac_per_vf is a bit ambiguous. From the description,
it seems to apply only to trusted VFs, but the name does not make that
obvious.
Would it make sense to either:
- Make the name reflect that (e.g., max_mac_per_trusted_vf), or
- Introduce two separate parameters for trusted and untrusted VFs if both
cases need to be handled differently?
I agree that the name could be a bit confusing. Since this is a generic
devlink parameter, different devices may handle trusted and untrusted
VFs differently.
For i40e specifically, the device does treat trusted VFs differently
from untrusted ones, and this is documented in devlink/i40e.rst.
However, I chose a more general name to avoid creating a separate
devlink parameter for untrusted VFs, which likely wouldn’t be used.
On reflection, I should update the patch number 1 to remove the
**trusted VF** wording from the description to avoid implying that the
parameter only applies to trusted VFs.
I believe the community generally aims for solutions that work
consistently across different hardware. If this parameter behaves
differently on i40e compared to mlx5 (or other drivers), it might be
helpful to mention that explicitly in the documentation or commit
message.
2)Problem statement
It would help to better understand the underlying problem this
parameter is solving.
Is the goal to enforce a global cap for all VFs, or to provide
operators with a way
to fine-tune per-VF limits? From my perspective, the most important
part is
clearly stating the problem and the use case.
My main goal here is to enforce a global cap for all VFs.
There was a long discussion [1] about this, and one of the ideas raised
was to create fine-tuned per-VF limits using devlink resources instead
of a parameter
However, currently in i40e, we only create a devlink port per PF and no
devlink ports per VF.
Implementing the resource-per-VF approach would therefore require some
extra work.
so i decided to go with this global cap for now.
[1] - https://patchwork.kernel.org/project/netdevbpf/
patch/[email protected]/ <https://
patchwork.kernel.org/project/netdevbpf/patch/20250805134042.2604897-2-
[email protected]/>
Thank, you Mohammad
The https://patchwork.kernel.org/project/netdevbpf/
patch/[email protected]/ <https://
patchwork.kernel.org/project/netdevbpf/patch/20250805134042.2604897-2-
[email protected]/> explains many things.
It might be helpful to include a brief description of the problem being
solved directly in the commit message. This gives reviewers the
necessary context and makes it easier to understand the motivation
behind the change.
…
