Re: [PATCH 1/3] xen/arm: Add memory overlap check for bootinfo.reserved_mem

[Julien Grall <julien@xxxxxxx>]

Hi Stefano,

On 12/12/2022 21:29, Stefano Stabellini wrote:
> > > > Personally, I think trying to share the code between the two types is a bit
> > > > odd. The logic is the same today, but I envision to merge reserved_mem,
> > > mem
> > > > and acpi in a single array (it would look like the E820) as this would make
> > > > easier to find the caching attributes per regions when mapping the RAM. So
> > > > sharing the code would not be possible.
> > > >
> > > > That said, if you really want to share the code between the two types. Then
> > > I
> > > > would prefer one of the following option:
> > > >     1) Provide a callback that is used to fetch the information from the array
> > > >     2) Provide a common structure that could be used by the function.
> > > >
> > > > This would match other generic function like sort & co.
> > > I think option 2) would be the best but I couldn't think of a simple way
> > > to do it (without using a union and I thought a union would not make
> > > things nicer in this case).
> > >
> > > Rather than option 1), I think I would rather have 2 different functions
> > > to check struct bootmodules and struct meminfo, or the macro.
> > I personally don't have specific taste here. I think the option
> > is good one as long as we can (1) share most part of the code (2) make the
> > code easy to extend in the future. So as long as you two reach
> > a consensus here I will change to the agreed method in v2.
> I think Julien and I already agree on having 2 separate functions to
> check for struct bootmodules and struct meminfo. Julien, I take you
> prefer the two separate functions to a MACRO, right?
In this case, yes because the macro would IMHO a bit too large.

Cheers,

--
Julien Grall