On Thu, Jan 16, 2020 at 11:57 AM Thomas Gleixner <t...@linutronix.de> wrote: > > Andy Lutomirski <l...@kernel.org> writes: > > On Thu, Jan 16, 2020 at 9:58 AM Christophe Leroy > > > > Would mul_u64_u64_shr() be a good alternative? Could we adjust it to > > assume the shift is less than 32? That function exists to benefit > > 32-bit arches. > > We'd want mul_u64_u32_shr() for this. The rules for mult and shift are: >
That's what I meant to type... > 1 <= mult <= U32_MAX > > 1 <= shift <= 32 > > If we want to enforce a shift < 32 we need to limit that conditionally > in the calculation/registration function. > > Thanks, > > tglx >