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. > Thanks >
