PERF_EVENT_FLAG_LEGACY
event->hw.flags |= PERF_EVENT_FLAG_LEGACY;
if (event->hw.flags & PERF_EVENT_FLAG_LEGACY) {
if (event->hw.flags & PERF_EVENT_FLAG_LEGACY) {
if ((hwc->flags & PERF_EVENT_FLAG_LEGACY) && (event->attr.type == PERF_TYPE_HARDWARE)) {