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Subject[PATCH 1/3] perf intel-pt: Fix recording PEBS-via-PT with registers
Date
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.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: 9e64cefe4335b ("perf intel-pt: Process options for PEBS event synthesis")
---
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 839ef52c1ac2..6ce451293634 100644
--- 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 a68ac3632ae6..ef802f6d40c1 100644
--- 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);
}
--
2.17.1
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