Re: [PATCH] MIPS: Loongson64: Give chance to build under !CONFIG_NUMA and !CONFIG_SMP

[Tiezhu Yang]

On 12/30/2020 12:39 AM, Thomas Bogendoerfer wrote:
> On Wed, Dec 16, 2020 at 10:44:23AM +0800, Tiezhu Yang wrote:
> > I have tested the following three configs on the Loongson platform:
> > (1) !NUMA and !SMP,
> > (2) !NUMA and SMP,
> > (3) NUMA and SMP,
> > everything is all right.
> >
> > But there exists the following build error under NUMA and !SMP:
> >
> >    CC      arch/mips/kernel/asm-offsets.s
> > In file included from ./include/linux/gfp.h:9:0,
> >                   from ./include/linux/xarray.h:14,
> >                   from ./include/linux/radix-tree.h:19,
> >                   from ./include/linux/fs.h:15,
> >                   from ./include/linux/compat.h:17,
> >                   from arch/mips/kernel/asm-offsets.c:12:
> > ./include/linux/topology.h: In function ‘numa_node_id’:
> > ./include/linux/topology.h:119:2: error: implicit declaration of function
> > ‘cpu_logical_map’ [-Werror=implicit-function-declaration]
> >    return cpu_to_node(raw_smp_processor_id());
> >    ^
> > cc1: some warnings being treated as errors
> > scripts/Makefile.build:117: recipe for target
> > 'arch/mips/kernel/asm-offsets.s' failed
> > make[1]: *** [arch/mips/kernel/asm-offsets.s] Error 1
> > arch/mips/Makefile:396: recipe for target 'archprepare' failed
> > make: *** [archprepare] Error 2
> >
> > I find a patch to fix this kind of build errors [1], but it seems
> > meaningless.
> >
> > According to the NUMA and SMP description in arch/mips/Kconfig,
> > we will use only one CPU of a multiprocessor machine if !SMP,
> > on single node systems leave NUMA disabled.
> >
> > So I think there is no need to use NUMA if !SMP, and also we should
> > make NUMA depend on SMP to avoid build errors.
> ok, but compiling IP27 with your patch gives
>
> WARNING: unmet direct dependencies detected for NUMA
>    Depends on [n]: SYS_SUPPORTS_NUMA [=y] && SMP [=n]
>    Selected by [y]:
>    - SGI_IP27 [=y] && <choice>
>
> WARNING: unmet direct dependencies detected for NUMA
>    Depends on [n]: SYS_SUPPORTS_NUMA [=y] && SMP [=n]
>    Selected by [y]:
>    - SGI_IP27 [=y] && <choice>
>
> WARNING: unmet direct dependencies detected for NUMA
>    Depends on [n]: SYS_SUPPORTS_NUMA [=y] && SMP [=n]
>    Selected by [y]:
>    - SGI_IP27 [=y] && <choice>
>
> If I use "select SMP" instead both ip27 and loongson64 compile.
>
> If you are ok with this change, I'll change it while appling your
> patch.

No problem, looks good to me, thank you very much.

Thanks,
Tiezhu
> Thomas.