> Subject: Re: [PATCH 07/22] RDMA/irdma: Register an auxiliary driver and > implement private channel OPs > > > > On 1/25/2021 9:29 PM, Leon Romanovsky wrote: > > On Mon, Jan 25, 2021 at 05:01:40PM -0800, Jacob Keller wrote: > >> > >> > >> On 1/25/2021 4:39 PM, Saleem, Shiraz wrote: > >>>> Subject: Re: [PATCH 07/22] RDMA/irdma: Register an auxiliary driver > >>>> and implement private channel OPs > >>>> > >>>> On Sun, Jan 24, 2021 at 03:45:51PM +0200, Leon Romanovsky wrote: > >>>>> On Fri, Jan 22, 2021 at 05:48:12PM -0600, Shiraz Saleem wrote: > >>>>>> From: Mustafa Ismail <mustafa.ismail@xxxxxxxxx> > >>>>>> > >>>>>> Register irdma as an auxiliary driver which can attach to > >>>>>> auxiliary RDMA devices from Intel PCI netdev drivers i40e and > >>>>>> ice. Implement the private channel ops, add basic devlink support > >>>>>> in the driver and register net notifiers. > >>>>> > >>>>> Devlink part in "the RDMA client" is interesting thing. > >>>>> > >>>>> The idea behind auxiliary bus was that PCI logic will stay at one > >>>>> place and devlink considered as the tool to manage that. > >>>> > >>>> Yes, this doesn't seem right, I don't think these auxiliary bus > >>>> objects should have devlink instances, or at least someone from > >>>> devlink land should approve of the idea. > >>>> > >>> > >>> In our model, we have one auxdev (for RDMA) per PCI device function > >>> owned by netdev driver and one devlink instance per auxdev. Plus there is an > Intel netdev driver for each HW generation. > >>> Moving the devlink logic to the PCI netdev driver would mean > >>> duplicating the same set of RDMA params in each Intel netdev driver. > >>> Additionally, plumbing RDMA specific params in the netdev driver sort of > seems misplaced to me. > >>> > >> > >> I agree that plumbing these parameters at the PCI side in the devlink > >> of the parent device is weird. They don't seem to be parameters that > >> the parent driver cares about. > >> > >> Maybe there is another mechanism that makes more sense? To me it is a > >> bit like if we were plumbing netdev specific paramters into devlink > >> instead of trying to expose them through netdevice specific > >> interfaces like iproute2 or ethtool. > > > > I'm far from being expert in devlink, but for me separation is following: > > 1. devlink - operates on physical device level, when PCI device already > initialized. > > 2. ethtool - changes needed to be done on netdev layer. > > 3. ip - upper layer of the netdev > > 4. rdmatool - RDMA specific when IB device already exists. > > > > And the ENABLE_ROCE/ENABLE_RDMA thing shouldn't be in the RDMA driver > > at all, because it is physical device property which once toggled will > > prohibit creation of respective aux device. > > > > Ok. I guess I hadn't looked quite as close at the specifics here. I agree that > ENABLE_RDMA should go in the PF devlink. > > If there's any other sort of RDMA-specific configuration that ties to the IB device, > that should go somehow into rdmatool, rather than devlink. And thus: I think I > agree, we don't want the IB device or the aux device to create a devlink instance. > I think rdma-tool might be too late for this type of param. We need the protocol info (iWARP vs RoCE) early on driver probe.
