perf intel-pt: Fix recording PEBS-via-PT with registers

When recording PEBS-via-PT, the kernel will not accept the intel_pt
event with register sampling e.g.

 # perf record --kcore -c 10000 -e '{intel_pt/branch=0/,branch-loads/aux-output/ppp}' -I -- ls -l
 Error:
 intel_pt/branch=0/: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'

Fix by suppressing register sampling on the intel_pt evsel.

Committer notes:

Adrian informed that this is only available from Tremont onwards, so on
older processors the error continues the same as before.

Fixes: 9e64cef ("perf intel-pt: Process options for PEBS event synthesis")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Luwei Kang <luwei.kang@intel.com>
Link: http://lore.kernel.org/lkml/20200630133935.11150-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/arch/x86/util/intel-pt.c

@@ -641,6 +641,7 @@ static int intel_pt_recording_options(struct auxtrace_record *itr,
 			}
 			evsel->core.attr.freq = 0;
 			evsel->core.attr.sample_period = 1;
+			evsel->no_aux_samples = true;
 			intel_pt_evsel = evsel;
 			opts->full_auxtrace = true;
 		}

tools/perf/util/evsel.c

@@ -1014,12 +1014,12 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts,
 	if (callchain && callchain->enabled && !evsel->no_aux_samples)
 		evsel__config_callchain(evsel, opts, callchain);
 
-	if (opts->sample_intr_regs) {
+	if (opts->sample_intr_regs && !evsel->no_aux_samples) {
 		attr->sample_regs_intr = opts->sample_intr_regs;
 		evsel__set_sample_bit(evsel, REGS_INTR);
 	}
 
-	if (opts->sample_user_regs) {
+	if (opts->sample_user_regs && !evsel->no_aux_samples) {
 		attr->sample_regs_user |= opts->sample_user_regs;
 		evsel__set_sample_bit(evsel, REGS_USER);
 	}