Re: Some guidance/suggestion please

[Martin Husemann <martin%duskware.de@localhost>]

On Fri, Jan 14, 2022 at 09:11:08AM -0800, Paul Goyette wrote:
> 	#ifdef ALTQ
> 		altq-code-part-A
> 	#endif
> 		(common code)
> 	#ifdef ALTQ
> 		altq-code-part-B
> 	#endif
> 	...
> 
> The existing module_hook mechanism doesn't help us here.  We can
> make the two pieces of altq code into module hooks, but that
> doesn't handle the case where the module gets loaded or unloaded
> between the two parts of the altq code.

I guess the same thing will happen when we make more networking things
loadable: each interface needs to "attach to altq", and if altq is loaded
later, it needs a way to iterate all interfaces "at some convenient
time" and do the necessary fixup. Same for unloading altq.

That way the interface driver can set a "altq present" flag at attach time
and only do the part A and part B calls if that flag is set.

Martin