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: 9e64cefe4335b ("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>

diff --git a/tools/perf/arch/x86/util/intel-pt.c b/tools/perf/arch/x86/util/intel-pt.c
index 839ef52c1ac22851914cd186ae5279e86716af1e..6ce451293634e398e0d53c6d666eae6108d631cb 100644 (file)
--- a/tools/perf/arch/x86/util/intel-pt.c
+++ b/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;
                }

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index a68ac3632ae6881a43b76e9f9c20f1a17b023cc0..ef802f6d40c17a27e8560fad8ccb9fb65fd30ebc 100644 (file)
--- a/tools/perf/util/evsel.c
+++ b/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);
        }