Re: [PATCH v4 1/7] riscv: asm: alternative-macros: Introduce ALTERNATIVE_3() macro

From: Conor Dooley
Date: Thu Nov 24 2022 - 15:05:57 EST


On Thu, Nov 24, 2022 at 08:58:41PM +0100, Heiko Stübner wrote:
> Am Donnerstag, 24. November 2022, 20:52:33 CET schrieb Conor Dooley:
> > On Thu, Nov 24, 2022 at 05:22:01PM +0000, Prabhakar wrote:
> > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > >
> > > Introduce ALTERNATIVE_3() macro.
> >
> > Bit perfunctory I think! There's a lovely comment down below that would
> > make for a better commit message if you were to yoink it.
> > Content looks about what I'd expect to see though.
>
> Also both the comment on the original ALTERNATIVE_2 and the new ALTERNATIVE_3
> should probably be merged into a single comment explaining this once for all
> ALTERNATIVE_x variants.
>
> Especially with the dma stuff, I'm pretty sure we'll get at least an ALTERNATIVE_4
> if not even more ;-) . So we defnitly don't want to repeat this multiple times.

Oh I can promise you that there'll be a #4 ;) I do find the comment's
wording to be quite odd though..

> + * A vendor wants to replace an old_content, but another vendor has used
> + * ALTERNATIVE_2() to patch its customized content at the same location. In

In particular this bit about "at the same location" does not make all
that much sense. What "at the same location" means in this context
should be expanded on imo. Effectively it boils down to someone else is
already replacing the same things you want to replace - it's just the
word "location" that might make sense if you're an old hand but not
otherwise?

> + * this case, this vendor can create a new macro ALTERNATIVE_3() based

Also, using the word "can". Is it not a "must" rather than a "can",
since this stuff needs to be multiplatform?

> + * on the following sample code and then replace ALTERNATIVE_2() with
> + * ALTERNATIVE_3() to append its customized content.