tprof_backend_register
int tprof_backend_register(const char *, const tprof_backend_ops_t *, int);
error = tprof_backend_register("tprof_armv7", &tprof_armv7_pmu_ops,
error = tprof_backend_register("tprof_armv8", &tprof_armv8_pmu_ops,
return tprof_backend_register(name, ops, TPROF_BACKEND_VERSION);