Re: [PATCH net-next V4 02/14] documentation: networking: add shared devlink documentation

From: Jiri Pirko

Date: Wed Dec 03 2025 - 05:36:17 EST


Tue, Dec 02, 2025 at 07:14:44PM +0100, kuba@xxxxxxxxxx wrote:
>On Tue, 2 Dec 2025 08:43:49 +0100 Jiri Pirko wrote:
>> Mon, Dec 01, 2025 at 10:49:54PM +0100, kuba@xxxxxxxxxx wrote:
>> >On Mon, 1 Dec 2025 11:50:08 +0100 Jiri Pirko wrote:
>> >> Correct. IFAIK there is one PF devlink instance per NUMA node.
>> >
>> >You say "correct" and then disagree with what I'm saying. I said
>> >ports because a port is a devlink object. Not a devlink instance.
>>
>> Okay, you mean devlink_port. You would like to see NUMA node leg as
>> devlink_port? Having troubles to undestand exactly what you mean, lot of
>> guessing on my side. Probably I'm slow, sorry.
>>
>> But there is a PCI device per NUMA node leg. Not sure how to model it.
>> Devink instances have 1:1 relationship with bus devices.
>>
>> Care to draw a picture perhaps?
>>
>> >> The shared instance on top would make sense to me. That was one of
>> >> motivations to introduce it. Then this shared instance would hold
>> >> netdev, vf representors etc.
>> >
>> >I don't understand what the shared instance is representing and how
>> >user is expect to find their way thru the maze of devlink instanced,
>> >for real bus, aux bus, and now shared instanced.
>>
>> Well, I tried to desrtibe it in the documentation path, Not sure what is
>> not clear :/
>>
>> Nested devlinks expose the connections between devlink instances.
>
>To be clear -- I understand how you're laying things out. My point is
>not about that. My question is how can user make intuitive sense of this
>mess of random object floating around. Every SW engineering problem can
>be solved by another layer of abstraction, that's not the challenge.
>The challenge is to design those layers so that they make intuitive
>sense (to people who don't spend their life programming against mlx FW
>interfaces).

Well, this really has no relation to mlx FW interfaces. It is a generic
issue of having multiple PFs backed by 1 physical device sharing
resources. How to make things more intuitive, I don't know :/ Any
suggestion?