perf auxtrace: Do not mix up mmap idx

The idx is with respect to evlist not evsel. That hasn't mattered because
they are the same at present. Prepare for that not being the case, which it
won't be when sideband tracking events are allowed on all CPUs even when
auxtrace is limited to selected CPUs.

Signed-off-by: Adrian Hunter <[e-mail]>
Acked-by: Ian Rogers <[e-mail]>
Cc: Alexey Bayduraev <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Leo Yan <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/util/auxtrace.c

···
 {
 	bool per_cpu_mmaps = !perf_cpu_map__empty(evlist->core.user_requested_cpus);
 
-	if (per_cpu_mmaps)
-		return perf_evsel__enable_cpu(&evsel->core, idx);
+	if (per_cpu_mmaps) {
+		struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->core.all_cpus, idx);
+		int cpu_map_idx = perf_cpu_map__idx(evsel->core.cpus, evlist_cpu);
+
+		if (cpu_map_idx == -1)
+			return -EINVAL;
+		return perf_evsel__enable_cpu(&evsel->core, cpu_map_idx);
+	}
 
 	return perf_evsel__enable_thread(&evsel->core, idx);
 }