Re: [PATCH V4 4/4] LoongArch: Enable ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP

[Arnd Bergmann]

On Mon, Jul 4, 2022 at 1:25 PM Huacai Chen <chenhuacai@xxxxxxxxxxx> wrote:
> To avoid the following build error on LoongArch we should include linux/
> static_key.h in page-flags.h.
>
> In file included from ./include/linux/mmzone.h:22,
> from ./include/linux/gfp.h:6,
> from ./include/linux/mm.h:7,
> from arch/loongarch/kernel/asm-offsets.c:9:
> ./include/linux/page-flags.h:208:1: warning: data definition has no
> type or storage class
> 208 | DECLARE_STATIC_KEY_MAYBE(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP_DEFAULT_ON,
> | ^~~~~~~~~~~~~~~~~~~~~~~~
> ./include/linux/page-flags.h:208:1: error: type defaults to 'int' in
> declaration of 'DECLARE_STATIC_KEY_MAYBE' [-Werror=implicit-int]
> ./include/linux/page-flags.h:209:26: warning: parameter names (without
> types) in function declaration

I wonder if page_fixed_fake_head() should be moved out of line to avoid
this, it's already nontrivial here, and that would avoid the static key
in a central header.

       Arnd