bfq_stat_read
sum += bfq_stat_read(stat) + atomic64_read(&stat->aux_cnt);
u64 samples = bfq_stat_read(&bfqg->stats.avg_queue_size_samples);
v = bfq_stat_read(&bfqg->stats.avg_queue_size_sum);
atomic64_add(bfq_stat_read(from) + atomic64_read(&from->aux_cnt),
return __blkg_prfill_u64(sf, pd, bfq_stat_read((void *)pd + off));