On Thu, Jul 07, 2016 at 05:04:34PM +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.rutl...@arm.com>
> Cc: Adrian Hunter <adrian.hun...@intel.com>
> Cc: Alexander Shishkin <alexander.shish...@linux.intel.com>
> Cc: Arnaldo Carvalho de Melo <a...@kernel.org>
> Cc: He Kuang <heku...@huawei.com>
> Cc: Ingo Molnar <mi...@redhat.com>
> Cc: Jiri Olsa <jo...@kernel.org>
> Cc: Peter Zijlstra <pet...@infradead.org>
> Cc: Wang Nan <wangn...@huawei.com>
> Cc: linux-kernel@vger.kernel.org
> ---
> tools/perf/util/evlist.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> index e82ba90..0b5b1be 100644
> --- a/tools/perf/util/evlist.c
> +++ b/tools/perf/util/evlist.c
> @@ -984,17 +984,24 @@ static int __perf_evlist__mmap(struct perf_evlist
> *evlist, int idx,
> }
>
> static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
> - struct mmap_params *mp, int cpu,
> + struct mmap_params *mp, int cpu_idx,
> int thread, int *output)
> {
> struct perf_evsel *evsel;
> + int evlist_cpu = cpu_map__cpu(evlist->cpus, cpu_idx);
>
> evlist__for_each(evlist, evsel) {
> int fd;
> + int cpu;
>
> if (evsel->system_wide && thread)
> continue;
>
> + if (!cpu_map__has(evsel->cpus, evlist_cpu))
> + continue;
> +
> + cpu = cpu_map__idx(evsel->cpus, evlist_cpu);
you basicaly call cpu_map__idx twice in here,
I think it might be better call it just once
and check the cpu for -1
jirka
