So far, it's impossible to validate timestamp trace in Arm CoreSight when the perf is in the per-thread mode. E.g. for the command:
perf record -e cs_etm/timestamp/ --per-thread -- ls
The command enables config 'timestamp' for 'cs_etm' event in the per-thread mode. In this case, the function cs_etm_validate_config() directly bails out and skips validation.
Given profiled process can be scheduled on any CPUs in the per-thread mode, this patch validates timestamp tracing for all CPUs when detect the CPU map is empty.
Signed-off-by: Leo Yan leo.yan@linaro.org --- tools/perf/arch/arm/util/cs-etm.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/tools/perf/arch/arm/util/cs-etm.c b/tools/perf/arch/arm/util/cs-etm.c index b8d6a953fd74..cf9ef9ba800b 100644 --- a/tools/perf/arch/arm/util/cs-etm.c +++ b/tools/perf/arch/arm/util/cs-etm.c @@ -205,8 +205,17 @@ static int cs_etm_validate_config(struct auxtrace_record *itr, for (i = 0; i < cpu__max_cpu().cpu; i++) { struct perf_cpu cpu = { .cpu = i, };
- if (!perf_cpu_map__has(event_cpus, cpu) || - !perf_cpu_map__has(online_cpus, cpu)) + /* + * In per-cpu case, do the validation for CPUs to work with. + * In per-thread case, the CPU map is empty. Since the traced + * program can run on any CPUs in this case, thus don't skip + * validation. + */ + if (!perf_cpu_map__empty(event_cpus) && + !perf_cpu_map__has(event_cpus, cpu)) + continue; + + if (!perf_cpu_map__has(online_cpus, cpu)) continue;
err = cs_etm_validate_context_id(itr, evsel, i);