Re: [PATCH] kbuild: Remove CONFIG_DEBUG_SECTION_MISMATCH

[Peter Zijlstra]

On Fri, Apr 08, 2022 at 10:32:28PM +0200, Peter Zijlstra wrote:

> > > This weird option is having us upgrade quite a few 'inline' to
> > > '__always_inline'.
> > 
> > As is, the assumption that __init functions only call other __init
> > functions or __always_inline is a brittle house of cards that leads to
> > a "what color is your function" [0] scenario, and leads to code that
> > happens to not emit warnings for compiler X (or compiler X version Y).
> > There's also curious exceptions in modpost that look like memory leaks
> > to me.

So I don't see __always_inline that way (also I'm in the 'inline' should
be '__always_inline' camp).

To me inline is more like: 'instantiate that pattern *here*'. It's like
CPP macros, only less horrible. You get the code generated according to
the local rules (instrumentation yes/no, section, and whatever other
function attributes we have that affect code-gen).

So with inline we can get the same pattern instantiated a number of
different times, leading to different actual code, without having to
type the whole thing multiple times (which would be terrible for
maintenance) etc..

Combine __always_inline with constant propagation of inline function
'pointers' and you get do beautiful things ;-) /me runs