Re: [PATCH v5 2/5] driver core: Functional dependencies tracking support

From: Greg Kroah-Hartman
Date: Wed Nov 09 2016 - 04:41:45 EST


On Wed, Nov 09, 2016 at 10:36:54AM +0100, Andrzej Hajda wrote:
> On 09.11.2016 07:45, Greg Kroah-Hartman wrote:
> > On Tue, Nov 08, 2016 at 09:58:24PM +0100, Luis R. Rodriguez wrote:
> >>>> Furthermore -- how does this framework compare to Andrzej's resource tracking
> >>>> solution? I confess I have not had a chance yet to review yet but in light of
> >>>> this question it would be good to know if Andrzej's framework also requires
> >>>> deferred probe as similar concerns would exist there as well.
> >>> I have no idea what "framework" you are talking about here, do you have
> >>> a pointer to patches?
> >> I'm surprised given Andrzej did both Cc you on his patches [2] *and* chimed
> >> in on Rafael's patches to indicate that we likely can integrate PM concerns
> >> into his own "framework" [3]. There was no resolution to this discussion, however
> >> its not IMHO sufficient to brush off Andrzej's points in particular because
> >> Andrzej *is* indicating that his framework:
> > Dude, those patches were from 2014! I can't remember patches people
> > sent to me a month ago...
> >
> >> - Eliminates deferred probe and resulting late_initcall(), consumer registers
> >> callbacks informing when given resources (clock, regulator, etc) becomes
> >> available
> >> - Properly handle resource disappearance (driver unbind, hotplug)
> >> - Track resources which are not vital to the device, but can influence behavior
> >> - Offers simplified resource allocation
> >> - Can be easily expanded to help with power management
> >>
> >> Granted I have not reviewed this yet but it at least was on my radar, and
> >> I do believe its worth reviewing this further given the generally expressed
> >> interest to see if we can have a common framework to address both ordering
> >> problems, suspend and probe. At a quick glance the "ghost provider" idea
> >> seems like a rather crazy idea but hey, there may be some goods in there.
> > >From what I remember, and I could be totally wrong, these patches were
> > way too complex and required that every subsystem change their
> > interfaces. That's not going to work out well, but read the email
> > threads for the details...
>
> I haven't seen your comment on my patches, except few general questions
> regarding one of earlier version of the framework.
> So maybe you are talking about different framework.
>
> Regarding complexity, if the subsystem have simple way of
> '(un)publishing' resources it just adds single calls to restrack core:
> restrack_up, restrack_down in proper places.
> Additionally it adds quite simple stuff to encapsulate resource
> description and allocation routines into generic *_restrack_desc
> structure, see for example patch adding restrack to phy framework[1].

Ok, again, I have no idea what my response was to a 2 year-old patchset,
again, I can't remember my response to a patchset that was sent just a
month ago...

update it, and repost and we can all go from there if you think it is a
viable solution.

thanks,

greg k-h