Paolo Abeni [off-list ref] writes:

On 7/31/24 23:13, Donald Hunter wrote:

quoted

Paolo Abeni [off-list ref] writes:

quoted

+        name: inputs
+        type: nest
+        multi-attr: true
+        nested-attributes: ns-info
+        doc: |
+           Describes a set of inputs shapers for a @group operation

The @group renders exactly as-is in the generated htmldocs. There may be
a more .rst friendly markup you can use that will render better.

Uhm... AFAICS the problem is the target (e.g. 'group') is outside the htmldoc section itself, I
can't find any existing markup to serve this purpose well. What about sticking to quotes ''
everywhere?

FTR, I used @ following the kdoc style.

Yeah, I was just thinking of using .rst markup like ``code`` or
`italics`, but the meaning of @ is pretty obvious when reading the spec.
If you stick with @ then we could always teach ynl-to-rst to render it
as ``code``.

[...]

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+    -
+      name: group
+      doc: |
+        Group the specified input shapers under the specified
+        output shaper, eventually creating the latter, if needed.
+        Input shapers scope must be either @queue or @detached.

It says above that you cannot create a detached shaper, so how do you
create one to use as an input shaper here? Is this group op more like a
multi-create op?

The group operation has the main goal of configuring a single WRR or SP scheduling group
atomically. It can creates the needed shapers as needed, see below.

The need for such operation sparks from some H/W constraints:

https://lore.kernel.org/netdev/9dd818dc-1fef-4633-b388-6ce7272f9cb4@lunn.ch/ (local)

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+        Output shaper scope must be either @detached or @netdev.
+        When using an output @detached scope shaper, if the
+        @handle @id is not specified, a new shaper of such scope
+        is created and, otherwise the specified output shaper
+        must be already existing.
+        The operation is atomic, on failures the extack is set
+        accordingly and no change is applied to the device
+        shaping configuration, otherwise the output shaper
+        handle is provided as reply.
+      attribute-set: net-shaper
+      flags: [ admin-perm ]

Does there need to be a reciprocal 'ungroup' operation? Without it,
create / group / delete seems like they will have ambiguous semantics.

I guess we need a better description. Can you please tell where/how the current one is
ambiguous?

My expectation for 'group' would be to group existing things, with a
reciprocal 'ungroup' operation. I think you intend 'group' to both be
able to group existing shapers/groups and create a group of shapers.

Am I right in saying that delete lets you delete something from a group
(with side-effect of deleting group if it becomes empty), or delete a
whole group?

It feels a lot like each of 'set', 'group' and 'delete' are doing
multiple things and the interaction between them all becomes challenging
to describe, or to handle all the corner cases. I think part of the
problem is the mixed terminology of input, output for groups, handle,
parent for shapers and using detached to differentiate from 'implicitly
attached to a resource'.

Perhaps the API would be better if you had:

- shaper-new
- shaper-delete
- shaper-get/dump
- shaper-set
- group-new
- group-delete
- group-get/dump
- group-set

If you went with Jakub's suggestion to give every shaper n x inputs and
an output, then you could recombine groups and shapers and just have 4
ops. And you could rename 'detached' to 'shaper' so that an attachment
is one of port, netdev, queue or shaper.