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Date: Thu, 6 Oct 2022 13:22:54 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>
Subject: Re: [PATCH v3 5/6] powerpc/64: Add support for out-of-line static calls
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On Thu, Oct 06, 2022 at 11:39:50AM +1100, Michael Ellerman wrote:
> Christophe Leroy <christophe.leroy@csgroup.eu> writes:
> > However, thinking out loudly, I'm wondering, could we make things any 
> > simpler when CONFIG_MODULES is not selected, or is that a too much 
> > corner case on PPC64 ?
> 
> I'd say it's mostly a corner case.
> 
> Obviously no distros ship with modules disabled. 
> 
> AFAIK even the stripped down kernels we use in CPU bringup have modules
> enabled.
> 
> So I think it's probably not worth worrying about, unless there's an
> obvious and fairly simple optimisation.

Long ago I built kernels that fit together with the boot firmware and a
root fs (busybox+dropbear essentially) in 4MB, but I doubt we can get
close to that at all these days :-)

What is the overhead if you enable modules but do not use them, these
days?


Segher