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Commit da4b6eff authored by Adrian Hunter's avatar Adrian Hunter Committed by Greg Kroah-Hartman
Browse files

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



[ 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: 9e64cefe ("perf intel-pt: Process options for PEBS event synthesis")
Signed-off-by: default avatarAdrian 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: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
parent 9ca67a45

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

+1 −0
Original line number Diff line number Diff line
@@ -596,6 +596,7 @@ 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

+2 −2
Original line number Diff line number Diff line
@@ -1028,12 +1028,12 @@ 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);

	}