Re: [dpdk-dev] [EXT] RE: [PATCH v2 1/4] ethdev: add tm support for shaper config in pkt mode

[Nithin Dabilpuram <ndabilpuram@marvell.com>]

On Tue, Apr 21, 2020 at 10:23:11AM +0000, Dumitrescu, Cristian wrote:
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> ----------------------------------------------------------------------
> Hi Nithin,
> 
> <snip>...
> 
> > > You are missing the shaper_shared_(packet, byte)_mode supported for
> > non-leaf and leaf nodes in struct rte_tm_level_capabilities.
> > >
> > > The description of this nodes should be aligned with the description of e.g.
> > shaper_shared_n_max field: basically, we want to say that, when true, the
> > flag signifies there is at least on non-leaf/leaf node on this level that can be
> > part of a shared shaper that works in packet/byte mode. Makes sense?
> > 
> > I intentionally didn't add shaper_shared_(packet, byte)_mode in node and
> > level
> > capabilities and added it in only global cap assuming existing semantics are
> > enforcing that.
> > 
> > Currently, except for 'shaper_shared_n_max', all the other existing shared
> > shaper capabilities like
> > shaper_shared_dual_rate_n_max, shaper_shared_rate_min, etc are only
> > provided in global cap.
> > 
> > I felt the semantics are as such because, shared shaper doesn't really belong
> > to any node
> > or level and any node from any level can attach to a particular shared shaper.
> > Isn't it so
> > ?
> 
> That's exactly why we need to formulate node/level capability from node's perspective, and not from the shared shaper's perspective, as a shared shaper is by definition related to a set of nodes, not just one node.
> 
> The fact that a given node can be part of a shared shaper that works in packet or byte mode, etc is a node capability in itself, right? So the node's capability called "shaper_shared_(packet, byte)_mode" being supported by the node means that this specific node can be part of a shared shaper that has those properties. To me, this is a valuable thing to capture in node/level capabilities.
> 
> We already have other node level capabilities for shared shaper, and we apply the same rationale there.
> 
> What do you think?
Ok. I'll add them from the node's perspective. 
Thanks.

> 
> Regards,
> Cristian