Re: [PATCH v2 0/4] Perf tool: Enable Arm arch timer counter and arm-spe's timestamp

[John Garry]

On 13/08/2020 12:18, Will Deacon wrote:
> [ Adding John, as I only just realised he wasn't on CC and we were talking
>    about him! ]
>
> On Thu, Aug 13, 2020 at 10:59:01AM +0100, Will Deacon wrote:
> > On Wed, Aug 12, 2020 at 03:53:34PM -0300, Arnaldo Carvalho de Melo wrote:
> > > Em Wed, Aug 12, 2020 at 10:06:53AM -0600, Mathieu Poirier escreveu:
> > > > The ARM SPE perf tools code is orphan and I don't have the cycles to
> > > > pick it up.  Leo has spent a lot of time in that code and as such I
> > > > suggest that he starts maintaining it, probably following the same
> > > > kind of arrangement you and I have for coresight.
> > >
> > > Thats ok with me, I think we should reflect that on the MAINTAINERS
> > > file, right?
> > >
> > > We have this already:
> > >
> > > PERFORMANCE EVENTS SUBSYSTEM ARM64 PMU EVENTS
> > > R:      John Garry <john.garry@xxxxxxxxxx>
> > > R:      Will Deacon <will@xxxxxxxxxx>
> > > L:      linux-arm-kernel@xxxxxxxxxxxxxxxxxxx (moderated for non-subscribers)
> > > S:      Supported
> > > F:      tools/perf/pmu-events/arch/arm64/
> > >
> > > I think we should have entries for CoreSight and ARM SPE, one listing
> > > you as the maintainer and the other listing Leo, right?
> >
> > Fine by me. I'll continue to maintain the in-kernel SPE driver, but I'd love
> > to see somebody step up to looking after the userspace code. It's seriously
> > unloved on arm64 :(
> >
> > I'd even be happy to see one or two M: entries added for
> > tools/perf/pmu-events/arch/arm64/. I realistically don't have the time to
> > take that on, but I'd be thrilled if any/all of John, Mathieu and Leo were
> > to be listed there if they are willing to do so and can spare the time to
> > look after it. Even just silly things like making sure the thing
> > cross-compiles have been broken in the recent past, so it's not necessarily
> > about handling huge amounts of incoming patches.
> >
> > In other words, rather than slice up the arm64 parts of the perf tool, I'd
> > argue in favour of a joint maintainership model for all the arm64 bits, if
> > we have a few willing volunteers.

Right, it makes sense not to chop up too much, so happy to see 
"PERFORMANCE EVENTS SUBSYSTEM ARM64 PMU EVENTS" expanded in terms of 
scope and membership.