Re: [RFCv2 3/4] perf: util: only open events on CPUs an evsel permits

From: Arnaldo Carvalho de Melo
Date: Mon Jul 18 2016 - 18:46:18 EST


Em Mon, Jul 18, 2016 at 04:32:59PM +0200, Jiri Olsa escreveu:
> On Fri, Jul 15, 2016 at 11:08:12AM +0100, Mark Rutland wrote:
> > In systems with heterogeneous CPU PMUs, it's possible for each evsel to
> > cover a distinct set of CPUs, and hence the cpu_map associated with each
> > evsel may have a distinct idx<->id mapping. Any of these may be distinct from
> > the evlist's cpu map.
> >
> > Events can be tied to the same fd so long as they use the same per-cpu
> > ringbuffer (i.e. so long as they are on the same CPU). To acquire the
> > correct FDs, we must compare the Linux logical IDs rather than the evsel
> > or evlist indices.
> >
> > This path adds logic to perf_evlist__mmap_per_evsel to handle this,
> > translating IDs as required. As PMUs may cover a subset of CPUs from the
> > evlist, we skip the CPUs a PMU cannot handle.
> >
> > Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx>
> > Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> > Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
> > Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> > Cc: He Kuang <hekuang@xxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> > Cc: Wang Nan <wangnan0@xxxxxxxxxx>
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
>
> Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>

Applied the first two, this one is not applying, please check my
perf/core branch, what is there should soon be pushed to Ingo, so
tip/perf/core may be ok too.

- Arnaldo