[dpdk-dev] [PATCH v3 08/10] eal/windows: fix rte_page_sizes with Clang on Windows

[Jerin Jacob]

On Wed, Apr 15, 2020 at 1:16 AM Dmitry Kozlyuk <dmitry.kozliuk at gmail.com> wrote:
>
> Clang on Windows follows MS ABI where enum values are limited to 2^31-1.
> Enum rte_page_size has members valued above this limit, which get
> wrapped to zero, resulting in compilation error (duplicate values in
> enum). Using MS ABI is mandatory for Windows EAL to call Win32 APIs.
>
> Define these values outside of the enum for Clang on Windows only.
> This does not affect runtime, because Windows doesn't run on machines
> with 4GiB and 16GiB hugepages.
>
> Signed-off-by: Dmitry Kozlyuk <dmitry.kozliuk at gmail.com>
> ---
>  lib/librte_eal/include/rte_memory.h | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/lib/librte_eal/include/rte_memory.h b/lib/librte_eal/include/rte_memory.h
> index 1b7c3e5df..3ec673f51 100644
> --- a/lib/librte_eal/include/rte_memory.h
> +++ b/lib/librte_eal/include/rte_memory.h
> @@ -34,8 +34,14 @@ enum rte_page_sizes {
>         RTE_PGSIZE_256M  = 1ULL << 28,
>         RTE_PGSIZE_512M  = 1ULL << 29,
>         RTE_PGSIZE_1G    = 1ULL << 30,
> +/* Work around Clang on Windows being limited to 32-bit underlying type. */

It does look like "enum rte_page_sizes" NOT used as enum anywhere.

[master][dpdk.org] $ grep -ri "enum rte_page_sizes" lib/
lib/librte_eal/include/rte_memory.h:enum rte_page_sizes {

Why not remove this workaround and define all items as #define to
avoid below ifdef clutter.

> +#if !defined(RTE_CC_CLANG) || !defined(RTE_EXEC_ENV_WINDOWS)

See above.

>         RTE_PGSIZE_4G    = 1ULL << 32,
>         RTE_PGSIZE_16G   = 1ULL << 34,
> +#else
> +#define RTE_PGSIZE_4G  (1ULL << 32)
> +#define RTE_PGSIZE_16G (1ULL << 34)
> +#endif
>  };
>
>  #define SOCKET_ID_ANY -1                    /**< Any NUMA socket. */
> --
> 2.25.1
>