On Thu, 20 May 2021 09:47:58 +0100 Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> wrote: > make W=1 generates the following warning for mm/page_alloc.c > > mm/page_alloc.c:3651:15: warning: no previous prototype for > ‘should_fail_alloc_page’ [-Wmissing-prototypes] noinline bool > should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) > ^~~~~~~~~~~~~~~~~~~~~~ > > This function is deliberately split out for BPF to allow errors to be > injected. The function is not used anywhere else so it is local to > the file. Make it static which should still allow error injection > to be used similar to how block/blk-core.c:should_fail_bio() works. > > Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> > --- > mm/page_alloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > index aaa1655cf682..26cc1a4e639b 100644 > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -3648,7 +3648,7 @@ static inline bool > __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) > #endif /* CONFIG_FAIL_PAGE_ALLOC */ > > -noinline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int > order) +static noinline bool should_fail_alloc_page(gfp_t gfp_mask, > unsigned int order) { > return __should_fail_alloc_page(gfp_mask, order); > } Hi Mel, It seems that this breaks builds with CONFIG_DEBUG_INFO_BTF=y. Maybe that warning was a false positive because should_fail_alloc_page() is referenced via a macro? I proposed to revert it, feel free to propose another fix. Regards, -- per aspera ad upstream