Re: [PATCH v7 1/8] unicode: Add utf8_casefold_iter

From: Daniel Rosenberg
Date: Fri Feb 14 2020 - 16:47:53 EST


On Tue, Feb 11, 2020 at 7:38 PM Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
>
> Indirect function calls are expensive these days for various reasons, including
> Spectre mitigations and CFI. Are you sure it's okay from a performance
> perspective to make an indirect call for every byte of the pathname?
>
> > +typedef int (*utf8_itr_actor_t)(struct utf8_itr_context *, int byte, int pos);
>
> The byte argument probably should be 'u8', to avoid confusion about whether it's
> a byte or a Unicode codepoint.
>
> - Eric

Gabriel, what do you think here? I could change it to either exposing
the things necessary to do the hashing in libfs, or instead of the
general purpose iterator, just have a hash function inside of unicode
that will compute the hash given a seed value.
-Daniel