Re: [PATCH v3 00/10] sh: remove NUMA and SPARSEMEM support

[John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>]

Hi,

On Thu, 2026-07-02 at 12:37 +0300, Mike Rapoport (Microsoft) wrote:
> Hi,
> 
> NUMA support for SuperH was introduced a long time ago by commit
> b241cb0c885e ("sh: Support for multiple nodes.")
> 
>         "... for boards with many different memory blocks that are
>          otherwise unused (SH7722/SH7785 URAM and so forth)"
> 
> In reality, this added 128K of memory on sh7722 and sh7785 and 256K on
> shx3 at the expense of all the NUMA related code in the kernel.
> 
> For build of v7.0-rc7 with defconfig and the same configuration with
> CONFIG_NUMA disabled, bloat-o-meter reports difference of ~76k. Disabling
> CONFIG_SPARSMEM on top increases the difference to ~94k. And that's only
> overhead in code and static data that does not take into the account data
> structures allocated at run time.
> 
> And all this overhead has been there for nothing for almost 8 years
> because since commit ac21fc2dcb40 ("sh: switch to NO_BOOTMEM")
> those additional "nodes" could not be used by the core MM because the
> maximal pfn for ZONE_NORMAL was cut out at the end of the normal memory.
> 
> ---
> It's been another few weeks without updates from Adrian and I don't see
> why it should wait more.
> 
> @Andrew, please take it to the mm tree.

I feel like this is an attempt to force me to give up as a maintainer.

Otherwise, I can't really understand why you are building up so much
pressure for a niche and hobbyist architecture

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
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