diff options
Diffstat (limited to 'tools/perf/util/cs-etm.c')
| -rw-r--r-- | tools/perf/util/cs-etm.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c index a9873d14c6..d65d748588 100644 --- a/tools/perf/util/cs-etm.c +++ b/tools/perf/util/cs-etm.c @@ -3346,12 +3346,27 @@ int cs_etm__process_auxtrace_info_full(union perf_event *event, etm->metadata = metadata; etm->auxtrace_type = auxtrace_info->type; - /* Use virtual timestamps if all ETMs report ts_source = 1 */ - etm->has_virtual_ts = cs_etm__has_virtual_ts(metadata, num_cpu); + if (etm->synth_opts.use_timestamp) + /* + * Prior to Armv8.4, Arm CPUs don't support FEAT_TRF feature, + * therefore the decoder cannot know if the timestamp trace is + * same with the kernel time. + * + * If a user has knowledge for the working platform and can + * specify itrace option 'T' to tell decoder to forcely use the + * traced timestamp as the kernel time. + */ + etm->has_virtual_ts = true; + else + /* Use virtual timestamps if all ETMs report ts_source = 1 */ + etm->has_virtual_ts = cs_etm__has_virtual_ts(metadata, num_cpu); if (!etm->has_virtual_ts) ui__warning("Virtual timestamps are not enabled, or not supported by the traced system.\n" - "The time field of the samples will not be set accurately.\n\n"); + "The time field of the samples will not be set accurately.\n" + "For Arm CPUs prior to Armv8.4 or without support FEAT_TRF,\n" + "you can specify the itrace option 'T' for timestamp decoding\n" + "if the Coresight timestamp on the platform is same with the kernel time.\n\n"); etm->auxtrace.process_event = cs_etm__process_event; etm->auxtrace.process_auxtrace_event = cs_etm__process_auxtrace_event; |