Re: [PATCH v3 08/12] arm64, numa: rework numa_add_memblk()

[Hanjun Guo]

Hi Robert,

On 03/09/2016 08:27 PM, Robert Richter wrote:
> On 23.01.16 17:39:23, Hanjun Guo wrote:
> > From: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> >
> > Rework numa_add_memblk() to update the parameter "u64 size"
> > to "u64 end", this will make it consistent with x86 and
> > can simplify the code later.
> >
> > Updates for arch/arm64/mm/numa.c should squash to core NUMA
> > patches from Ganapat.
> >
> > Signed-off-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> > ---
> >   arch/arm64/kernel/acpi_numa.c |  2 +-
> >   arch/arm64/kernel/of_numa.c   |  2 +-
> >   arch/arm64/mm/numa.c          | 12 ++++++------
> >   3 files changed, 8 insertions(+), 8 deletions(-)
>
> > diff --git a/arch/arm64/kernel/of_numa.c b/arch/arm64/kernel/of_numa.c
> > index 2f9e34b..aa6f3a3 100644
> > --- a/arch/arm64/kernel/of_numa.c
> > +++ b/arch/arm64/kernel/of_numa.c
> > @@ -168,7 +168,7 @@ static int __init early_init_parse_memory_node(unsigned long node)
> >   		pr_debug("NUMA-DT:  base = %llx , node = %u\n",
> >   				base, nid);
> >
> > -		if (numa_add_memblk(nid, base, size) < 0)
> > +		if (numa_add_memblk(nid, base, base + size) < 0)
> >   			return -EINVAL;
> >   	}
> >
> > diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
> > index e974995..2b04b8a 100644
> > --- a/arch/arm64/mm/numa.c
> > +++ b/arch/arm64/mm/numa.c
> > @@ -137,25 +137,25 @@ void numa_store_cpu_info(unsigned int cpu)
> >    * numa_add_memblk - Set node id to memblk
> >    * @nid: NUMA node ID of the new memblk
> >    * @start: Start address of the new memblk
> > - * @size:  Size of the new memblk
> > + * @end:  End address of the new memblk
>
> Apart from my earlier comment, this is not exactly correct and may
> cause confussion. The implementation here defines:
>
>   size == end - start
>
> which is different to struct resource, where:
>
>   resource_size(res) == res->end - res->start + 1
>
> Thus, @end here is the first address outside of memblk.
>
> This is one more argument for keeping @size here.

I agree :)

I'm working on the new version and met the problem of no
definition for numa_add_memblk() and numa_set_distance()
on IA64, numa_set_distance() seems to easy to add one for
IA64, but numa_add_memblk() is not, this will the blocker
for moving functions to common place, what's your opinion
here?

Also I'm thinking to move all the code in arch/arm64/kernel/acpi_numa.c
to the arch/arm64/kernel/acpi.c to make the ACPI code in ARM64
self-contained, what do you think?

Thanks
Hanjun