Re: [RFC PATCH 3/5] acpi/hmat: Track target address ranges

[Dan Williams]

On Thu, Apr 4, 2019 at 1:56 PM Keith Busch <kbusch@xxxxxxxxxx> wrote:
>
> On Thu, Apr 04, 2019 at 12:08:44PM -0700, Dan Williams wrote:
> > As of ACPI 6.3 the HMAT no longer advertises the physical memory address
> > range for its entries. Instead, the expectation is the corresponding
> > entry in the SRAT is looked up by the target proximity domain.
> >
> > Given there may be multiple distinct address ranges that share the same
> > performance profile (sparse address space), find_mem_target() is updated
> > to also consider the start address of the memory range. Target property
> > updates are also adjusted to loop over all possible 'struct target'
> > instances that may share the same proximity domain identification.
>
> Since this may allocate multiple targets with the same PXM,
> hmat_register_targets() will attempt to register the same node multiple
> times.
>
> Would it make sense if the existing struct memory_target adds a resource
> list that we can append to as we parse SRAT? That way we have one target
> per memory node, and also track the ranges.

That sounds reasonable to me.