Re: [PATCH 12/12] selftests/mm: fix uffd-unit-tests.c build failure due to missing MADV_COLLAPSE

[Muhammad Usama Anjum <usama.anjum@collabora.com>]

On 6/2/23 6:33 AM, John Hubbard wrote:
> MADV_PAGEOUT, MADV_POPULATE_READ, MADV_COLLAPSE are conditionally
> defined as necessary. However, that was being done in .c files, and a
> new build failure came up that would have been automatically avoided had
> these been in a common header file.
There is a better way. Just like I've mentioned that building in-tree
kernel headers and then mm selftests don't produce any build failures as
they pick up in-tree compiled kernel header files. Don't move these
definations to vm_util.h. Instead include asm-generic/mman-common.h which
has all these definitions already. I've just removed what you have removed
in this patch and include asm-generic/mman-common.h. It builds fine. But
then there are more duplicated definition warnings.

> 
> So consolidate and move them all to vm_util.h, which fixes the build
> failure.
> 
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> ---
>  tools/testing/selftests/mm/cow.c        |  7 -------
>  tools/testing/selftests/mm/khugepaged.c | 10 ----------
>  tools/testing/selftests/mm/vm_util.h    | 10 ++++++++++
>  3 files changed, 10 insertions(+), 17 deletions(-)
> 
> diff --git a/tools/testing/selftests/mm/cow.c b/tools/testing/selftests/mm/cow.c
> index dc9d6fe86028..8882b05ec9c8 100644
> --- a/tools/testing/selftests/mm/cow.c
> +++ b/tools/testing/selftests/mm/cow.c
> @@ -30,13 +30,6 @@
>  #include "../kselftest.h"
>  #include "vm_util.h"
>  
> -#ifndef MADV_PAGEOUT
> -#define MADV_PAGEOUT 21
> -#endif
> -#ifndef MADV_COLLAPSE
> -#define MADV_COLLAPSE 25
> -#endif
> -
>  static size_t pagesize;
>  static int pagemap_fd;
>  static size_t thpsize;
> diff --git a/tools/testing/selftests/mm/khugepaged.c b/tools/testing/selftests/mm/khugepaged.c
> index 97adc0f34f9c..e88ee039d0eb 100644
> --- a/tools/testing/selftests/mm/khugepaged.c
> +++ b/tools/testing/selftests/mm/khugepaged.c
> @@ -22,16 +22,6 @@
>  
>  #include "vm_util.h"
>  
> -#ifndef MADV_PAGEOUT
> -#define MADV_PAGEOUT 21
> -#endif
> -#ifndef MADV_POPULATE_READ
> -#define MADV_POPULATE_READ 22
> -#endif
> -#ifndef MADV_COLLAPSE
> -#define MADV_COLLAPSE 25
> -#endif
> -
>  #define BASE_ADDR ((void *)(1UL << 30))
>  static unsigned long hpage_pmd_size;
>  static unsigned long page_size;
> diff --git a/tools/testing/selftests/mm/vm_util.h b/tools/testing/selftests/mm/vm_util.h
> index 7f5aac0ac680..f04f82771cd0 100644
> --- a/tools/testing/selftests/mm/vm_util.h
> +++ b/tools/testing/selftests/mm/vm_util.h
> @@ -41,3 +41,13 @@ unsigned long default_huge_page_size(void);
>  
>  #define PAGEMAP_PRESENT(ent)	(((ent) & (1ull << 63)) != 0)
>  #define PAGEMAP_PFN(ent)	((ent) & ((1ull << 55) - 1))
> +
> +#ifndef MADV_PAGEOUT
> +#define MADV_PAGEOUT 21
> +#endif
> +#ifndef MADV_POPULATE_READ
> +#define MADV_POPULATE_READ 22
> +#endif
> +#ifndef MADV_COLLAPSE
> +#define MADV_COLLAPSE 25
> +#endif

-- 
BR,
Muhammad Usama Anjum