op_prepare_attr
op_prepare_attr(&attr, config->config, 0, 0);
op_prepare_attr(&attr, 0, period->freq, period->sample_freq);
op_prepare_attr(&attr, 0, ibs_ioctl->freq, 1000);
op_prepare_attr(&attr, 0x300D40, 1, 0);
op_prepare_attr(&attr, 0x10000, l3missonly->freq,