Re: [dpdk-dev] [RFC v2 1/9] usertools: add DPDK config lib python library

[Thomas Monjalon <thomas@monjalon.net>]

16/11/2018 16:43, Burakov, Anatoly:
> On 16-Nov-18 2:55 PM, Thomas Monjalon wrote:
> > 16/11/2018 15:37, Burakov, Anatoly:
> >> On 16-Nov-18 2:13 PM, Richardson, Bruce wrote:
> >>> From: Wiles, Keith
> >>>>> On Nov 16, 2018, at 5:49 AM, Burakov, Anatoly
> >>>>> On 16-Nov-18 12:45 AM, Stephen Hemminger wrote:
> >>>>>> Anatoly Burakov <anatoly.burakov@intel.com> wrote:
> >>>>>>> This is a placeholder for Python library abstracting away many of
> >>>>>>> mundane details DPDK configuration scripts have to deal with. We
> >>>>>>> need __init__.py file to make the subdirectory a package so that
> >>>>>>> Python scripts in usertools/ can find their dependencies.
> >>>>>>>
> >>>>>>> Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
> >>>>>>
> >>>>>> Doing this a better than current code, but can we go farther?
> >>>>>> I would like DPDK to get out of doing binds directly and switch to
> >>>>>> using driverctl which also handles persistent rebind on reboot.
> >>>>>
> >>>>> Wasn't the objection that it's not available everywhere? (for the
> >>>>> record, i have no horse in the race - i don't much care exactly how
> >>>>> it's done)
> >>>>
> >>>> If it works on FreeBSD and Linux then I am all for it. On windows does it
> >>>> support this method too?
> >>>
> >>> Binding and unbinding is completely different on each OS. FreeBSD has no overlap
> >>> of scripts with Linux, so replacing some of our tools with driverctl won't affect
> >>> that OS.
> >>>
> >>> /Bruce
> >>
> >> ...however, we could abstract that away in our tools, and use
> >> OS-appropriate tools independently of what we're running on. There could
> >> still be value in fixing devbind everyone knows and love to work on all
> >> OS's without too much hassle :)
> > 
> > Yes, easier script is always better.
> > 
> > Another thought, I would like we think about integrating binding/unbinding
> > code inside EAL and bus drivers, and manage it via the PMDs.
> > There could be an option to bind on scan and unbind on rte_dev_remove.
> 
> I didn't like it back when it was a thing, and i don't particularly like 
> this idea now, to be honest. Port binding should not be under purview of 
> the application, but is firmly in the domain of system administrator 
> IMO. I don't think it's our place to change system configuration while 
> we're running.

Yes I agree, administration should be done separately.
However, there are 3 scenarios to manage properly:
	- hotplug: can it be configured in advance?
	- dynamically release device to kernel
	- some drivers can share a device with the kernel