Re: [RFC PATCH 2/2] tools/perf: Make group_fd static and move itsplace in __perf_evsel__open()

[Arnaldo Carvalho de Melo]

Em Mon, Oct 24, 2011 at 12:03:28PM -0200, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Oct 24, 2011 at 06:57:00PM +0800, Deng-Cheng Zhu escreveu:
> > __perf_evsel__open() is called per event, it does not work for all the
> > grouped events at one time. So, currently group_fd will alway be -1 for
> > the events in a group. This patch fixes it.
> > 
> > Signed-off-by: Deng-Cheng Zhu <dczhu@xxxxxxxx>
> > Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
> > Cc: Paul Mackerras <paulus@xxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxx>
> > Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxxxxxxxxxx>
> > ---
> >  tools/perf/util/evsel.c |    3 +--
> >  1 files changed, 1 insertions(+), 2 deletions(-)
> > 
> > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> > index e389815..7bd0d9d 100644
> > --- a/tools/perf/util/evsel.c
> > +++ b/tools/perf/util/evsel.c
> > @@ -219,9 +219,8 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
> >  	}
> >  
> >  	for (cpu = 0; cpu < cpus->nr; cpu++) {
> > -		int group_fd = -1;
> > -
> >  		for (thread = 0; thread < threads->nr; thread++) {
> > +			static int group_fd = -1;
> >  
> >  			if (!evsel->cgrp)
> >  				pid = threads->map[thread];
> 
> Lets not do it that way, using statics for this is humm, ugly, IMHO.
> 
> Just pass an integer pointer that is a member of perf_evlist, I'll work
> on a patch now.
> 
> Thanks for reporting the bug tho! 

Can you try this patch?

I tested it with:

[root@emilia ~]# perf top -e cycles -e instructions --group

and

[root@emilia ~]# perf record -e cycles -e instructions --group -a sleep 2

Peter,

	Do you see anything wrong with it?

Thanks,

- Arnaldo