4.4-stable review patch. If anyone has any objections, please let me know.
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From: Adrian Hunter adrian.hunter@intel.com
commit 03997612904866abe7cdcc992784ef65cb3a4b81 upstream.
CYC packet timestamp calculation depends upon CBR which was being cleared upon overflow (OVF). That can cause errors due to failing to synchronize with sideband events. Even if a CBR change has been lost, the old CBR is still a better estimate than zero. So remove the clearing of CBR.
Signed-off-by: Adrian Hunter adrian.hunter@intel.com Cc: Jiri Olsa jolsa@redhat.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/20190206103947.15750-4-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 1 - 1 file changed, 1 deletion(-)
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c @@ -1281,7 +1281,6 @@ static int intel_pt_overflow(struct inte { intel_pt_log("ERROR: Buffer overflow\n"); intel_pt_clear_tx_flags(decoder); - decoder->cbr = 0; decoder->timestamp_insn_cnt = 0; decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC; decoder->overflow = true;