Re: [RFD/RFC PATCH 0/8] Towards implementing proxy execution

From: Juri Lelli
Date: Tue Oct 09 2018 - 08:36:06 EST


On 09/10/18 13:56, Daniel Bristot de Oliveira wrote:
> On 10/9/18 12:51 PM, Sebastian Andrzej Siewior wrote:
> >> The main concerns I have with the current approach is that, being based
> >> on mutex.c, it's both
> >>
> >> - not linked with futexes
> >> - not involving "legacy" priority inheritance (rt_mutex.c)
> >>
> >> I believe one of the main reasons Peter started this on mutexes is to
> >> have better coverage of potential problems (which I can assure everybody
> >> it had). I'm not yet sure what should we do moving forward, and this is
> >> exactly what I'd be pleased to hear your opinions on.
> > wasn't the idea that once it works to get rid of rt_mutex?

Looks like it was (see Peter's reply).

> As far as I know, it is. But there are some additional complexity
> involving a -rt version of this patch, for instance:
>
> What should the protocol do if the thread migrating is with migration
> disabled?
>
> The side effects of, for instance, ignoring the migrate_disable() would
> add noise for the initial implementation... too much complexity at once.
>
> IMHO, once it works in the non-rt, it will be easier to do the changes
> needed to integrate it with -rt.
>
> Thoughts?

Makes sense to me. Maybe we should just still keep in mind eventual
integration, so that we don't take decisions we would regret.