Re: [PATCH net-next v3 05/17] zinc: ChaCha20 x86_64 implementation

[Thomas Gleixner]

On Tue, 11 Sep 2018, Samuel Neves wrote:

> On Tue, Sep 11, 2018 at 9:22 AM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> > On Mon, 10 Sep 2018, Jason A. Donenfeld wrote:
> >>  lib/zinc/Makefile                        |    4 +
> >>  lib/zinc/chacha20/chacha20-x86_64-glue.h |  102 +
> >>  lib/zinc/chacha20/chacha20-x86_64.S      | 2632 ++++++++++++++++++++++
> >
> > Just a stupid question. What's the rationale of putting that into lib/zinc
> > instead of having it in arch/x86/crypto?
> >
> 
> This is covered on the 02/17 commit message, whose relevant paragraph follows:

Well, being only cc'ed on only half of the patches does not really help.

> > It also organizes the implementations in a simple, straight-forward,
> > and direct manner, making it enjoyable and intuitive to work on.
> > Rather than moving optimized assembly implementations into arch/, it
> > keeps them all together in lib/zinc/, making it simple and obvious to
> > compare and contrast what's happening. This is, notably, exactly what
> > the lib/raid6/ tree does, and that seems to work out rather well. It's
> > also the pattern of most successful crypto libraries. The architecture-
> > specific glue-code is made a part of each translation unit, rather than
> > being in a separate one, so that generic and architecture-optimized code
> > are combined at compile-time, and incompatibility branches compiled out by
> > the optimizer.

Fair enough.