Subject: Re: [PATCH v4 24/26] arch_numa: switch over to numa_memblks

From: Mike Rapoport <[email-masked]>
Date: Tue, 27 Aug 2024 11:52:55 +0300

Hi,

On Mon, Aug 26, 2024 at 06:17:22PM +0000, Bruno Faccini wrote:
> > On 7 Aug 2024, at 2:41, Mike Rapoport wrote:
> > 
> > From: "Mike Rapoport (Microsoft)" <[email-masked]>
> > 
> > Until now arch_numa was directly translating firmware NUMA information
> > to memblock.
> > 
> > Using numa_memblks as an intermediate step has a few advantages:
> > * alignment with more battle tested x86 implementation
> > * availability of NUMA emulation
> > * maintaining node information for not yet populated memory
> > 
> > Adjust a few places in numa_memblks to compile with 32-bit phys_addr_t
> > and replace current functionality related to numa_add_memblk() and
> > __node_distance() in arch_numa with the implementation based on
> > numa_memblks and add functions required by numa_emulation.
> > 
> > Signed-off-by: Mike Rapoport (Microsoft) <[email-masked]>
> > Tested-by: Zi Yan <[email-masked]> # for x86_64 and arm64
> > Reviewed-by: Jonathan Cameron <[email-masked]>
> > Tested-by: Jonathan Cameron <[email-masked]> [arm64 + CXL via
> > QEMU]
> > Acked-by: Dan Williams <[email-masked]>
> > Acked-by: David Hildenbrand <[email-masked]>
> > ---
> >   drivers/base/Kconfig       |   1 +
> >   drivers/base/arch_numa.c   | 201 +++++++++++--------------------------
> >   include/asm-generic/numa.h |   6 +-
> >   mm/numa_memblks.c          |  17 ++--
> >   4 files changed, 75 insertions(+), 150 deletions(-)
> >  
> > <snip>
> > 
> > +
> > +u64 __init numa_emu_dma_end(void)
> > +{
> > +             return PFN_PHYS(memblock_start_of_DRAM() + SZ_4G);
> > +}
> > +
> 
> PFN_PHYS() translation is unnecessary here, as
> memblock_start_of_DRAM() + SZ_4G is already a
> memory size.
> 
> This should fix it:
>  
> diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c
> index 8d49893c0e94..e18701676426 100644
> --- a/drivers/base/arch_numa.c
> +++ b/drivers/base/arch_numa.c
> @@ -346,7 +346,7 @@ void __init numa_emu_update_cpu_to_node(int
> *emu_nid_to_phys,
> 
> u64 __init numa_emu_dma_end(void)
> {
> -              return PFN_PHYS(memblock_start_of_DRAM() + SZ_4G);
> +             return memblock_start_of_DRAM() + SZ_4G;
> }
> 
> void debug_cpumask_set_cpu(unsigned int cpu, int node, bool enable)

Right, I've missed that. Thanks for the fix!

Andrew, can you please apply this (with fixed formatting)

diff --git a/drivers/base/arch_numa.c b/drivers/base/arch_numa.c
index 8d49893c0e94..e18701676426 100644
--- a/drivers/base/arch_numa.c
+++ b/drivers/base/arch_numa.c
@@ -346,7 +346,7 @@ void __init numa_emu_update_cpu_to_node(int *emu_nid_to_phys,
 
 u64 __init numa_emu_dma_end(void)
 {
-	return PFN_PHYS(memblock_start_of_DRAM() + SZ_4G);
+	return memblock_start_of_DRAM() + SZ_4G;
 }
 
 void debug_cpumask_set_cpu(unsigned int cpu, int node, bool enable)

-- 
Sincerely yours,
Mike.