[PATCH] erofs: Consider NUMA affinity when allocating memory for per-CPU pcpubuf

[Gao Xiang]

Hi RongQing,

On Mon, Apr 15, 2024 at 02:19:40PM +0800, Li RongQing wrote:
> per-CPU pcpubufs are dominantly accessed from their own local CPUs,
> so allocate them node-local to improve performance.
> 
> Signed-off-by: Li RongQing <lirongqing at baidu.com>

Thanks for your patch!  Yeah, NUMA-aware is important to
NUMA bare metal server scenarios.

In the next cycle, we also reduce the total number of buffers
since we don't such many per-CPU buffers if there are too many
CPUs: we called "global buffers" and maintain CPU->global
buffer mappings.  Also erofs_allocpage() won't be used to
allocate too.

For more details, see my for-next branch:
https://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git/log/?h=dev

So could you make some difference to make the new global
buffers NUMA-aware? (both for allocation and mapping, maybe
the allocation is still a priority stuff if per-CPU is needed
anyway.)

Thanks,
Gao Xiang