Re: [PATCH V2 3/6] perf tools: add infrastructure for PMU specific configuration

[Jiri Olsa]

On Wed, Jul 27, 2016 at 11:59:50AM -0600, Mathieu Poirier wrote:

SNIP

> > -PE_DRV_CFG_TERM
> > +'@' PE_NAME '=' PE_NAME
> >  {
> >         struct parse_events_term *term;
> >
> >         ABORT_ON(parse_events_term__str(&term, PARSE_EVENTS__TERM_TYPE_DRV_CFG,
> > -                                       $1, $1, &@1, NULL));
> > +                                       $2, $4, &@2, &@4));
> >         $$ = term;
> >  }
> >
> 
> The problem here is that the correlation between the first and the
> second PE_NAME is lost and instead of seeing "PE_NAME=PE_NAME", the
> kernel only gets the value associated with the second PE_NAME.
> 
> For example,
> 
> -e event/@cfg1=value1,@cfg2=value2/ ...
> 
> The above code will send "value1" and "value2" to the kernel driver
> where there is no way to know what configurable the values correspond

hum.. you get the 'cfg1' and 'cfg2' strings in $1 no?

jirka

> to.  To go around that we'd have to concatenate $2 and $4 in function
> parse_events_term__str() (or new_term()) when @type_term ==
> PARSE_EVENTS__TERM_TYPE_DRV_CFG, something that definitely looks
> hackish to me.
> 
> Thanks,
> Mathieu