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Date: Thu, 23 Aug 2018 15:09:57 +0200
From: Juri Lelli <juri.lelli@gmail.com>
Subject: Re: SCHED_DEADLINE as user
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To: luca abeni <luca.abeni@santannapisa.it>
Cc: Tim Blechmann <tim@klingt.org>, Daniel Bristot de Oliveira <daniel@bristot.me>, linux-rt-users@vger.kernel.org, Tommaso Cucinotta <tommaso.cucinotta@santannapisa.it>

On 23/08/18 15:00, luca abeni wrote:
> On Thu, 23 Aug 2018 14:37:39 +0200
> Juri Lelli <juri.lelli@gmail.com> wrote:
> [...]
> > > > Maybe the existing system wide sched_rt_{period,
> > > > runtime}_us are enough?  
> > > 
> > > I do not know... A cgroup-based interface looks more powerful (and
> > > not so difficult to implement... :), and would allow the sysadmin
> > > to decide which users can use SCHED_DEADLINE, how much
> > > SCHED_DEADLINE bandwidth can each user/group use, etc...  
> > 
> > How about extending PAM limits instead? It looks like it's what (e.g.)
> > audio users rely on already [1]. It is maybe possible to add
> > dlruntime, dlperiod, dldeadline parameters in there?
> 
> Ok, I do not know much about these PAM limits... Where can I find more
> information?

The link I shared already gives some information, man pam_limits and
limits.conf also.

> What do we need to implement exactly, to add these dlruntime,
> dlperiod, dldeadline parameters?

Not sure yet "exactly" :-), but I'd say something along these lines

https://elixir.bootlin.com/linux/latest/source/kernel/sched/core.c#L4198