Re: [dpdk-dev] [PATCH v2 01/15] mbuf: add definitions of unified packet types

[Bruce Richardson <bruce.richardson@intel.com>]

On Mon, Feb 09, 2015 at 02:40:35PM +0800, Helin Zhang wrote:
> As there are only 6 bit flags in ol_flags for indicating packet types,
> which is not enough to describe all the possible packet types hardware
> can recognize. For example, i40e hardware can recognize more than 150
> packet types. Unified packet type is composed of tunnel type, L3 type,
> L4 type and inner L3 type fields, and can be stored in mbuf field of
> 'packet_type' which is modified from 16 bits to 32 bits in mbuf structure.
> Accordingly, the structure of 'rte_kni_mbuf' needs to be modifed as well.
> 
> Signed-off-by: Helin Zhang <helin.zhang@intel.com>
> Signed-off-by: Cunming Liang <cunming.liang@intel.com>
> Signed-off-by: Jijiang Liu <jijiang.liu@intel.com>
> ---
>  .../linuxapp/eal/include/exec-env/rte_kni_common.h |   4 +-
>  lib/librte_mbuf/rte_mbuf.h                         | 113 +++++++++++++++++++--
>  2 files changed, 108 insertions(+), 9 deletions(-)
> 
> v2 changes:
> * Enlarged the packet_type field from 16 bits to 32 bits.
> * Redefined the packet type sub-fields.
> * Updated the 'struct rte_kni_mbuf' for KNI according to the mbuf changes.
>

Since these changes to the mbuf will break the operation of the vector driver,
that vector driver needs to be taken into account here.

Some suggestions/options:
1. Temporarily disable the VPMD at compile time or at run time as part of this
patch, and put the vector changes as the next patch (re-enabling the driver too)
2. Put in the minimum changes for the new mbuf layout into this patch. It will
make this patch a little longer, but may still be doable as it's only a couple
of fields changing, not the whole structure.

/Bruce