Re: [PATCH v1 2/2] selftests/mm: Guard defines from shm

Muhammad Usama Anjum
2024-06-07T10:02:55Z

On 6/6/24 3:36 AM, Edward Liaw wrote:
> thuge-gen.c defines SHM_HUGE_* macros that are provided by the uapi
> since 4.14. These macros get redefined when compiling with Android's
> bionic because its sys/shm.h will import the uapi definitions.
>
> However if linux/shm.h is included, with glibc, sys/shm.h will clash on
> some struct definitions:
>
> /usr/include/linux/shm.h:26:8: error: redefinition of ‘struct shmid_ds’
> 26 | struct shmid_ds {
> | ^~~~~~~~
> In file included from /usr/include/x86_64-linux-gnu/bits/shm.h:45,
> from /usr/include/x86_64-linux-gnu/sys/shm.h:30:
> /usr/include/x86_64-linux-gnu/bits/types/struct_shmid_ds.h:24:8: note: originally defined here
> 24 | struct shmid_ds
> | ^~~~~~~~
>
> For now, guard the SHM_HUGE_* defines with ifndef to prevent
> redefinition warnings on Android bionic.
LGTM
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>

>
> Signed-off-by: Edward Liaw <edliaw@google.com>
> ---
> tools/testing/selftests/mm/thuge-gen.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/tools/testing/selftests/mm/thuge-gen.c b/tools/testing/selftests/mm/thuge-gen.c
> index 034635317935..d50dc71cac32 100644
> --- a/tools/testing/selftests/mm/thuge-gen.c
> +++ b/tools/testing/selftests/mm/thuge-gen.c
> @@ -34,10 +34,18 @@
> #endif
>
> #define SHM_HUGETLB 04000 /* segment will use huge TLB pages */
> +#ifndef SHM_HUGE_SHIFT
> #define SHM_HUGE_SHIFT 26
> +#endif
> +#ifndef SHM_HUGE_MASK
> #define SHM_HUGE_MASK 0x3f
> +#endif
> +#ifndef SHM_HUGE_2MB
> #define SHM_HUGE_2MB (21 << SHM_HUGE_SHIFT)
> +#endif
> +#ifndef SHM_HUGE_1GB
> #define SHM_HUGE_1GB (30 << SHM_HUGE_SHIFT)
> +#endif
>
> #define NUM_PAGESIZES 5
> #define NUM_PAGES 4

--
BR,
Muhammad Usama Anjum