On Mon, Nov 09, 2020 at 11:03:25AM +0200, Gal Pressman wrote: > > On 09/11/2020 7:09, Leon Romanovsky wrote: > > On Sun, Nov 08, 2020 at 07:49:35PM -0400, Jason Gunthorpe wrote: > >> On Sun, Nov 08, 2020 at 03:03:45PM +0200, Gal Pressman wrote: > >>> On 05/11/2020 22:00, Jason Gunthorpe wrote: > >>>> On Tue, Nov 03, 2020 at 05:45:26PM +0200, Gal Pressman wrote: > >>>>> On 03/11/2020 16:22, Jason Gunthorpe wrote: > >>>>>> On Tue, Nov 03, 2020 at 04:11:19PM +0200, Gal Pressman wrote: > >>>>>>> On 03/11/2020 15:57, Leon Romanovsky wrote: > >>>>>>>> On Tue, Nov 03, 2020 at 09:45:22AM -0400, Jason Gunthorpe wrote: > >>>>>>>>> On Tue, Nov 03, 2020 at 03:26:27PM +0200, Gal Pressman wrote: > >>>>>>>>>> Add the ability to query the device's bdf through rdma tool netlink > >>>>>>>>>> command (in addition to the sysfs infra). > >>>>>>>>>> > >>>>>>>>>> In case of virtual devices (rxe/siw), the netdev bdf will be shown. > >>>>>>>>> > >>>>>>>>> Why? What is the use case? > >>>>>>>> > >>>>>>>> Right, and why isn't netdev (RDMA_NLDEV_ATTR_NDEV_NAME) enough? > >>>>>>> > >>>>>>> When taking system topology into consideration you need some way to pair the > >>>>>>> ibdev and bdf, especially when working with multiple devices. > >>>>>>> The netdev name doesn't exist on devices with no netdevs (IB, EFA). > >>>>>> > >>>>>> You are supposed to use sysfs > >>>>>> > >>>>>> /sys/class/infiniband/ibp0s9/device > >>>>>> > >>>>>> Should always be the physical device > >>>>>> > >>>>>>> Why rdma tool? Because it's more intuitive than sysfs. > >>>>>> > >>>>>> But we generally don't put this information into netlink BDF is just > >>>>>> the start, you need all the other topology information to make sense > >>>>>> of it, and all that is in sysfs only already > >>>>> > >>>>> As the commit message says, it's in addition to the device sysfs. > >>>>> > >>>>> Many (if not most) of the existing rdma netlink commands are duplicates of some > >>>>> sysfs entries, but show it in a more "modern" way. > >>>>> I'm not convinced that bdf should be treated differently. > >>>> > >>>> Why did you call it BDF anyhow? it has nothing to do with PCI BDF > >>>> other than it happens to be the PDF for PCI devices. Netdev called > >>>> this bus_info > >>> > >>> Are there non pci devices in the subsystem? > >> > >> Yes, HNS uses non-pci devices > >> > >>> I can rename to a more fitting name, will change to bus_info unless > >>> someone has a better idea. > >> > >> The thing is, is is still useless. You have to consult sysfs to > >> understand what bus it is scoped on to do anything further with > >> it. Can't just assume it is PCI. > > > > Can anyone please remind me why are we doing it? > > What problem do you solve here by adding new nldev attributes? > > https://lore.kernel.org/linux-rdma/0825e1bf-f913-d2c1-ad3f-35ba3d6b75ef@xxxxxxxxxx/ Thanks, but IMHO it doesn't answer on the question about the problem.
