perf intel-pt: Fix error recovery from missing TIP packet

commit 1c196a6c771c47a2faa63d38d913e03284f73a16 upstream.

When a TIP packet is expected but there is a different packet, it is an
error. However the unexpected packet might be something important like a
TSC packet, so after the error, it is necessary to continue from there,
rather than the next packet. That is achieved by setting pkt_step to
zero.

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/1520431349-30689-4-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
index 00f25f4b5f484b6ff920e0dfaa6bcb6cde46c9ea..5e4d0bbafc8bde9cdcd9b7117e068db5c03d1f6e 100644 (file)
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -1616,6 +1616,7 @@ static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
                case INTEL_PT_PWRX:
                        intel_pt_log("ERROR: Missing TIP after FUP\n");
                        decoder->pkt_state = INTEL_PT_STATE_ERR3;
+                       decoder->pkt_step = 0;
                        return -ENOENT;
 
                case INTEL_PT_OVF: