[RFC PATCH 2/5] perf jevents: add support for arch recommended events
jolsa at redhat.com
Mon Jan 8 06:08:40 PST 2018
On Thu, Jan 04, 2018 at 05:17:56PM +0000, John Garry wrote:
> Hi Jirka,
> Sorry for the slow reply.
np, just got back from holidays anyway ;-)
> > > > Won't this all potentially have a big maintainence cost?
> > as Andi said it's mostly just the disk space,
> > which is not big deal
> > I'm not doing JSON file updates, but I think having
> > simple single dir for platform/cpu could save us some
> > confusion in future
> Understood. But for ARM, which has very standardised architecture events, it
> is good to reduce this event duplication between platforms.
> > however I won't oppose if you want to add this logic,
> > but please:
> > - use the list_head ;-)
> Of course
> > - leave the process_one_file function simple
> > and separate the level0 processing
> ok, this is how it should look already, albeit a couple of
> process_one_file() modifications. I'll re-check this.
> > - you are using 'EventCode' as an unique ID to find
> > the base, but it's not unique for x86, you'll need
> > to add some other ID scheme that fits to all archs
> Right, so you mentioned earlier using a new keyword token to identify
> whether we use the standard event, so we can go his way - ok?
yes, something like that
> I would also like to mention at this point why I did the event
> pre-processing in jevents, and not a separate script:
> - current build does not transverse the arch tree
> - tree transversal for JSON processing is done in jevents
> - a script would mean derived objects, which means:
> - makefile changes for derived objects
> - jevents would have to deal with derived objects
> - jevents already has support for JSON processing
> The advantage of using a script is that we keep the JSON processing in
> jevents simple.
I don't mind the extra functionality in jevents as long as the current
one keeps on working and the new one works for all archs ;-)
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