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

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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: 9e64cefe43 ("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>
This commit is contained in:
Adrian Hunter
2020-06-30 16:39:33 +03:00
committed by Arnaldo Carvalho de Melo
parent d61cbb859b
commit 75bcb8776d
2 changed files with 3 additions and 2 deletions
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tools/perf/arch/x86/util/intel-pt.c
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@@ -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;
}