Re: [PATCH] eal: increase max file descriptor for secondary process device

[Ferruh Yigit <ferruh.yigit@amd.com>]

On 9/5/2024 5:20 PM, Stephen Hemminger wrote:
> The TAP and XDP driver both are limited to only 8 queues when
> because of the small limit imposed by EAL. Increase the limit
> now since this release allows changing ABI.
> 
> Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
> ---
>  doc/guides/rel_notes/release_24_11.rst | 5 +++++
>  lib/eal/include/rte_eal.h              | 2 +-
>  2 files changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/doc/guides/rel_notes/release_24_11.rst b/doc/guides/rel_notes/release_24_11.rst
> index 0ff70d9057..5af70e04c5 100644
> --- a/doc/guides/rel_notes/release_24_11.rst
> +++ b/doc/guides/rel_notes/release_24_11.rst
> @@ -100,6 +100,11 @@ ABI Changes
>     Also, make sure to start the actual text at the margin.
>     =======================================================
>  
> +* The maximum number of file descriptors that can be passed to a secondary process
> +  has been increased from 8 to 253 (which is the maximum possible with Unix domain
> +  socket). This allows for more queues when using software devices such as TAP
> +  and XDP.
> +
>  
>  Known Issues
>  ------------
> diff --git a/lib/eal/include/rte_eal.h b/lib/eal/include/rte_eal.h
> index c2256f832e..c826e143f1 100644
> --- a/lib/eal/include/rte_eal.h
> +++ b/lib/eal/include/rte_eal.h
> @@ -155,7 +155,7 @@ int rte_eal_primary_proc_alive(const char *config_file_path);
>   */
>  bool rte_mp_disable(void);
>  
> -#define RTE_MP_MAX_FD_NUM	8    /* The max amount of fds */
> +#define RTE_MP_MAX_FD_NUM	253  /* The max amount of fds (see SCM_MAX_FD) */
>  #define RTE_MP_MAX_NAME_LEN	64   /* The max length of action name */
>  #define RTE_MP_MAX_PARAM_LEN	256  /* The max length of param */
>  struct rte_mp_msg {
>

It would be nice to add this to deprecation notice first, but it seems
we missed, I think it is safe to update in ABI break release and good to
remove this restriction.

Acked-by: Ferruh Yigit <ferruh.yigit@amd.com>