On Tue, Dec 19, 2023 at 10:42:46AM +0800, Jingbo Xu wrote:
> } else {
> bdi->max_ratio = max_ratio;
> - bdi->max_prop_frac = (FPROP_FRAC_BASE * max_ratio) / 100;
> + bdi->max_prop_frac = div64_u64(FPROP_FRAC_BASE * max_ratio,
> + 100 * BDI_RATIO_SCALE);
> }
Why use div64_u64 here?
FPROP_FRAC_BASE is an unsigned long. max_ratio is an unsigned int, so
the numerator is an unsigned long. BDI_RATIO_SCALE is 10,000, so the
numerator is an unsigned int. There's no 64-bit arithmetic needed here.
