[PATCH 69/73] perf intel-pt: Fix sample timestamp wrt non-taken branches

[Arnaldo Carvalho de Melo]

From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

The sample timestamp is updated to ensure that the timestamp represents
the time of the sample and not a branch that the decoder is still
walking towards. The sample timestamp is updated when the decoder
returns, but the decoder does not return for non-taken branches. Update
the sample timestamp then also.

Note that commit 3f04d98e972b5 ("perf intel-pt: Improve sample
timestamp") was also a stable fix and appears, for example, in v4.4
stable tree as commit a4ebb58fd124 ("perf intel-pt: Improve sample
timestamp").

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v4.4+
Fixes: 3f04d98e972b ("perf intel-pt: Improve sample timestamp")
Link: http://lkml.kernel.org/r/20190510124143.27054-4-adrian.hunter@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

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 9cbd587489bf..f4c3c84b090f 100644
--- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
+++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
@@ -1318,8 +1318,11 @@ static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
 				return 0;
 			}
 			decoder->ip += intel_pt_insn.length;
-			if (!decoder->tnt.count)
+			if (!decoder->tnt.count) {
+				decoder->sample_timestamp = decoder->timestamp;
+				decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 				return -EAGAIN;
+			}
 			decoder->tnt.payload <<= 1;
 			continue;
 		}
-- 
2.20.1