Mon, Nov 11, 2019 at 03:58:18PM CET, parav@xxxxxxxxxxxx wrote: > > >> -----Original Message----- >> From: Jiri Pirko <jiri@xxxxxxxxxxx> >> Sent: Monday, November 11, 2019 8:18 AM >> Sun, Nov 10, 2019 at 08:48:31PM CET, parav@xxxxxxxxxxxx wrote: >> > >> >> From: Jason Gunthorpe <jgg@xxxxxxxx> >> >> Sent: Friday, November 8, 2019 6:57 PM >> >> > We should be creating 3 different buses, instead of mdev bus being >> >> > de- >> >> multiplexer of that? >> >> > >> >> > Hence, depending the device flavour specified, create such device >> >> > on right >> >> bus? >> >> > >> >> > For example, >> >> > $ devlink create subdev pci/0000:05:00.0 flavour virtio name foo >> >> > subdev_id 1 $ devlink create subdev pci/0000:05:00.0 flavour mdev >> >> > <uuid> subdev_id 2 $ devlink create subdev pci/0000:05:00.0 flavour >> >> > mlx5 id 1 subdev_id 3 >> >> >> >> I like the idea of specifying what kind of interface you want at sub >> >> device creation time. It fits the driver model pretty well and >> >> doesn't require abusing the vfio mdev for binding to a netdev driver. >> >> >> >> > $ devlink subdev pci/0000:05:00.0/<subdev_id> config <params> $ >> >> > echo <respective_device_id> <sysfs_path>/bind >> >> >> >> Is explicit binding really needed? >> >No. >> > >> >> If you specify a vfio flavour why shouldn't the vfio driver autoload >> >> and bind to it right away? That is kind of the point of the driver >> >> model... >> >> >> >It some configuration is needed that cannot be passed at device creation >> time, explicit bind later can be used. >> > >> >> (kind of related, but I don't get while all that GUID and lifecycle >> >> stuff in mdev should apply for something like a SF) >> >> >> >GUID is just the name of the device. >> >But lets park this aside for a moment. >> > >> >> > Implement power management callbacks also on all above 3 buses? >> >> > Abstract out mlx5_bus into more generic virtual bus (vdev bus?) so >> >> > that multiple vendors can reuse? >> >> >> >> In this specific case, why does the SF in mlx5 mode even need a bus? >> >> Is it only because of devlink? That would be unfortunate >> >> >> >Devlink is one part due to identifying using bus/dev. >> >How do we refer to its devlink instance of SF without bus/device? >> >> Question is, why to have devlink instance for SF itself. Same as VF, you don't >mlx5_core has devlink instance for PF and VF for long time now. >Health report, txq/rxq dumps etc all anchored to this devlink instance even for VF. (similar to PF). >And so, SF same framework should work for SF. Right, for health it makes sense. > >> need devlink instance. You only need devlink_port (or >> devlink_subdev) instance on the PF devlink parent for it. >> >Devlink_port or devlink_subdev are still on eswitch or mgmt side. >They are not present on the side where devlink instance exist on side where txq/rxq/eq etc exist. > Got it.
