From: Florian Fainelli <f.faine...@gmail.com> Date: Mon, 9 Jan 2017 12:56:48 -0800
> 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? I would definitely prefer to see cached state used instead of this deferred operation stuff.
