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Date:   Tue, 9 Oct 2018 11:58:35 +0200
From:   Juri Lelli <juri.lelli@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     mingo@redhat.com, rostedt@goodmis.org, tglx@linutronix.de,
        linux-kernel@vger.kernel.org, luca.abeni@santannapisa.it,
        claudio@evidence.eu.com, tommaso.cucinotta@santannapisa.it,
        alessio.balsini@gmail.com, bristot@redhat.com, will.deacon@arm.com,
        andrea.parri@amarulasolutions.com, dietmar.eggemann@arm.com,
        patrick.bellasi@arm.com, henrik@austad.us,
        linux-rt-users@vger.kernel.org
Subject: Re: [RFD/RFC PATCH 0/8] Towards implementing proxy execution
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 <20181009094441.GI5663@hirez.programming.kicks-ass.net>
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On 09/10/18 11:44, Peter Zijlstra wrote:
> On Tue, Oct 09, 2018 at 11:24:26AM +0200, Juri Lelli 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.
> 
> Well that, and mutex was 'simple', I didn't have to go rip out all the
> legacy PI crud.

Indeed.

> If this all ends up working well, the solution is 'simple' and we can
> simply copy mutex to rt_mutex or something along those lines if we want
> to keep the distinction between them. Alternatively we simply delete
> rt_mutex.

Ah.. right.. sounds *scary*, but I guess it might be an option after
all.

> Thanks for reviving this.. it's been an 'interesting' year and a half
> since I wrote all this and I've really not had time to work on it.

n/p, it has been a long standing thing to look at for me as well. Thanks
again for sharing your patches!