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Re: [PATCH 5/5] x86: don't build unused entry code when !PV32

  • To: Jan Beulich <jbeulich@xxxxxxxx>, Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
  • From: Roger Pau Monné <roger.pau@xxxxxxxxxx>
  • Date: Mon, 4 Jan 2021 16:53:58 +0100
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On Mon, Jan 04, 2021 at 02:56:12PM +0100, Jan Beulich wrote:
> On 28.12.2020 16:30, Roger Pau Monné wrote:
> > I would like to have Andrew's opinion on this one (as you and him tend
> > to modify more asm code than myself). There are quite a lot of
> > addition to the assembly code, and IMO it makes the code more complex
> > which I think we should try to avoid, as assembly is already hard
> > enough.
> Well, while I can see your point (and I indeed asked myself the same
> question when making this change), this merely follows the route
> started with the addition on CONFIG_PV conditionals. If we think that
> prior step didn't set a good precedent, we ought to undo it.
> Otherwise I see no good argument against doing the same kind of
> transformation a 2nd time (and further ones, if need be down the
> road).

I think we need to apply some common sense and reach consensus about
where it's fine to make code conditional at build time as to not make
the existing code much harder to read and reason about. This is mostly
a subjective decision, so I understand your concern.

I still think I would like Andrew opinion on this one, as said you and
him are the ones mostly doing assembly coding. I find it already hard
to follow myself without the conditionals.

Thanks, Roger.



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