[dpdk-dev] [RFC] mbuf: support dynamic fields and flags

[Stephen Hemminger]

On Wed, 10 Jul 2019 11:29:07 +0200
Olivier Matz <olivier.matz at 6wind.com> wrote:

>  /**
>   * Indicate that the metadata field in the mbuf is in use.
> @@ -738,6 +741,8 @@ struct rte_mbuf {
>  	 */
>  	struct rte_mbuf_ext_shared_info *shinfo;
>  
> +	uint64_t dynfield1; /**< Reserved for dynamic fields. */
> +	uint64_t dynfield2; /**< Reserved for dynamic fields. */
>  } __rte_cache_aligned;

Growing mbuf is a fundamental ABI break and this needs
higher level approval.  Why not one pointer?

It looks like you are creating something like FreeBSD m_tag.
Why not use that?