Mon, Jan 09, 2017 at 10:14:36PM CET, ido...@idosch.org wrote: >On Mon, Jan 09, 2017 at 12:56:48PM -0800, Florian Fainelli wrote: >> On 01/09/2017 12:48 PM, Ido Schimmel wrote: >> > Hi Florian, >> > >> > On Mon, Jan 09, 2017 at 11:44:59AM -0800, Florian Fainelli wrote: >> >> Hi all, >> >> >> >> This patch series is to resolve a sleeping function called in atomic >> >> context >> >> debug splat that we observe with DSA. >> >> >> >> Let me know what you think, I was also wondering if we should just always >> >> make switchdev_port_vlan_fill() set SWITCHDEV_F_DEFER, but was afraid this >> >> could cause invalid contexts to be used for rocker, mlxsw, i40e etc. >> > >> > Isn't this a bit of overkill? All the drivers you mention fill the VLAN >> > dump from their cache and don't require sleeping. Even b53 that you >> > mention in the last patch does that, but reads the PVID from the device, >> > which entails taking a mutex. >> >> Correct. >> >> > >> > Can't you just cache the PVID as well? I think this will solve your >> > problem. Didn't look too much into the b53 code, so maybe I'm missing >> > something. Seems that mv88e6xxx has a similar problem. >> >> I suppose we could indeed cache the PVID for b53, but for mv88e6xxx it >> seems like we need to perform a bunch of VTU operations, and those >> access HW registers, Andrew, Vivien, how do you want to solve that, do >> we want to introduce a general VLAN cache somewhere in switchdev/DSA/driver? > >Truth be told, I don't quite understand why switchdev infra even tries >to dump the VLANs from the device. Like, in which situations is this >going to be different from what the software bridge reports? Sure, you >can set the VLAN filters with SELF and skip the software bridge, but how >does that make sense in a model where you want to reflect the software >datapath?
But the vlans added by rtnl_bridge_setlink & SELF are not tracked by the bridge and therefore driver needs to dump them. You would have to pass some flag down to driver when adding SWITCHDEV_OBJ_ID_PORT_VLAN indicating the need to track the vlan and dump it. Right?
