Re: [PATCH 3/3] MIPS: Use memblock_add_node() in early_parse_mem() under CONFIG_NUMA

[Tiezhu Yang]

On 03/22/2022 09:19 PM, Jiaxun Yang wrote:
> 在 2022/3/18 15:05, Tiezhu Yang 写道:
> > Use memblock_add_node to add new memblock region within a NUMA node
> > in early_parse_mem() under CONFIG_NUMA, otherwise the mem parameter
> > can not work well.
>
> Hi Tiezhu,
>
> pa_to_nid doesn't exist when CONFIG_NUME is disabled.
> So probably you want #ifdef macro instead ？

Hi Jiaxun,

Thank you for your reply.

As far as I can tell, if CONFIG_NUMA is set, IS_ENABLED(CONFIG_NUMA)
is 1, pa_to_nid() is defined in the platform dependent header file:

	arch/mips/include/asm/mach-ip27/mmzone.h
	arch/mips/include/asm/mach-loongson64/mmzone.h

if CONFIG_NUMA is not set, IS_ENABLED(CONFIG_NUMA) is 0, pa_to_nid()
is always 0 which is defined in arch/mips/include/asm/mmzone.h:

	#ifdef CONFIG_NUMA
	# include <mmzone.h>
	#endif

	#ifndef pa_to_nid
	#define pa_to_nid(addr) 0
	#endif

So pa_to_nid() is defined under both CONFIG_NUMA and !CONFIG_NUMA,
there is no build error.

Additionally, use #ifdef CONFIG_NUMA is also OK, but I prefer to
use IS_ENABLED(CONFIG_NUMA).

If I am missing something, please let me know, thank you.

Thanks,
Tiezhu

> Thanks.
> - Jiaxun
>
> > Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
> > ---
> >   arch/mips/kernel/setup.c | 6 +++++-
> >   1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
> > index c8c8f60..50cdc08 100644
> > --- a/arch/mips/kernel/setup.c
> > +++ b/arch/mips/kernel/setup.c
> > @@ -37,6 +37,7 @@
> >   #include <asm/cdmm.h>
> >   #include <asm/cpu.h>
> >   #include <asm/debug.h>
> > +#include <asm/mmzone.h>
> >   #include <asm/sections.h>
> >   #include <asm/setup.h>
> >   #include <asm/smp-ops.h>
> > @@ -378,7 +379,10 @@ static int __init early_parse_mem(char *p)
> >               memblock_end_of_DRAM() - memblock_start_of_DRAM());
> >       }
> >   -    memblock_add(start, size);
> > +    if (IS_ENABLED(CONFIG_NUMA))
> > +        memblock_add_node(start, size, pa_to_nid(start), MEMBLOCK_NONE);
> > +    else
> > +        memblock_add(start, size);
> >         return 0;
> >   }