From: Adrian Hunter adrian.hunter@intel.com
[ Upstream commit 75bcb8776dc987538f267ba4ba05ca43fc2b1676 ]
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 Signed-off-by: Sasha Levin sashal@kernel.org --- tools/perf/arch/x86/util/intel-pt.c | 1 + tools/perf/util/evsel.c | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-)
diff --git a/tools/perf/arch/x86/util/intel-pt.c b/tools/perf/arch/x86/util/intel-pt.c index 1643aed8c4c8e..2a548fbdf2a2a 100644 --- a/tools/perf/arch/x86/util/intel-pt.c +++ b/tools/perf/arch/x86/util/intel-pt.c @@ -634,6 +634,7 @@ 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 eb880efbce16d..386950f29792a 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1048,12 +1048,12 @@ void perf_evsel__config(struct evsel *evsel, struct record_opts *opts, if (callchain && callchain->enabled && !evsel->no_aux_samples) perf_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; perf_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; perf_evsel__set_sample_bit(evsel, REGS_USER); }