Add default sink selection to the perf trace handling in the etm driver. Uses the select default sink infrastructure to select a sink for the perf session, if no other sink is specified. Signed-off-by: Mike Leach <mike.leach@xxxxxxxxxx> Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx> --- .../hwtracing/coresight/coresight-etm-perf.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 84f1dcb69827..1a3169e69bb1 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -226,9 +226,6 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, sink = coresight_get_enabled_sink(true); } - if (!sink) - goto err; - mask = &event_data->mask; /* @@ -253,6 +250,16 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, continue; } + /* + * No sink provided - look for a default sink for one of the + * devices. At present we only support topology where all CPUs + * use the same sink [N:1], so only need to find one sink. The + * coresight_build_path later will remove any CPU that does not + * attach to the sink, or if we have not found a sink. + */ + if (!sink) + sink = coresight_find_default_sink(csdev); + /* * Building a path doesn't enable it, it simply builds a * list of devices from source to sink that can be @@ -267,6 +274,10 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, *etm_event_cpu_path_ptr(event_data, cpu) = path; } + /* no sink found for any CPU - cannot trace */ + if (!sink) + goto err; + /* If we don't have any CPUs ready for tracing, abort */ cpu = cpumask_first(mask); if (cpu >= nr_cpu_ids) -- 2.17.1