ld_retired        558 arch/arm/kernel/perf_event_v7.c ARMV7_EVENT_ATTR(ld_retired, ARMV7_PERFCTR_MEM_READ);
ld_retired        171 arch/arm64/kernel/perf_event.c ARMV8_EVENT_ATTR(ld_retired, ARMV8_PMUV3_PERFCTR_LD_RETIRED);