diff options
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-etm-perf.c')
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-etm-perf.c | 29 |
1 files changed, 23 insertions, 6 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 8ebd728d3a80..3bce1ec4c4bf 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -452,9 +452,14 @@ static void etm_event_start(struct perf_event *event, int flags) * sink from this ETM. We can't do much in this case if * the sink was specified or hinted to the driver. For * now, simply don't record anything on this ETM. + * + * As such we pretend that everything is fine, and let + * it continue without actually tracing. The event could + * continue tracing when it moves to a CPU where it is + * reachable to a sink. */ if (!cpumask_test_cpu(cpu, &event_data->mask)) - goto fail_end_stop; + goto out; path = etm_event_cpu_path(event_data, cpu); /* We need a sink, no need to continue without one */ @@ -466,16 +471,15 @@ static void etm_event_start(struct perf_event *event, int flags) if (coresight_enable_path(path, CS_MODE_PERF, handle)) goto fail_end_stop; - /* Tell the perf core the event is alive */ - event->hw.state = 0; - /* Finally enable the tracer */ if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF)) goto fail_disable_path; +out: + /* Tell the perf core the event is alive */ + event->hw.state = 0; /* Save the event_data for this ETM */ ctxt->event_data = event_data; -out: return; fail_disable_path: @@ -485,7 +489,7 @@ fail_end_stop: perf_aux_output_end(handle, 0); fail: event->hw.state = PERF_HES_STOPPED; - goto out; + return; } static void etm_event_stop(struct perf_event *event, int mode) @@ -517,6 +521,19 @@ static void etm_event_stop(struct perf_event *event, int mode) if (WARN_ON(!event_data)) return; + /* + * Check if this ETM was allowed to trace, as decided at + * etm_setup_aux(). If it wasn't allowed to trace, then + * nothing needs to be torn down other than outputting a + * zero sized record. + */ + if (handle->event && (mode & PERF_EF_UPDATE) && + !cpumask_test_cpu(cpu, &event_data->mask)) { + event->hw.state = PERF_HES_STOPPED; + perf_aux_output_end(handle, 0); + return; + } + if (!csdev) return; |