+Cc more maintainers
19/05/2020 20:41, tal...@mellanox.com:
> From: Tal Shnaiderman <tal...@mellanox.com>
>
> Using uint32_t type bit-fields in Windows will pads the
> 'L2/L3/L4 and tunnel information' union with additional bits.
>
> This padding causes rte_mbuf size misalignment and the total size
> increases to 3 cache-lines.
>
> Changed packet_type bit-fields types from uint32_t to uint8_t
> to allow unified 2 cache-line structure size.
>
> Added the __extension__ attribute over the modified struct to avoid
> the warning:
>
> type of bit-field ... is a GCC extension [-pedantic]
>
> Signed-off-by: Tal Shnaiderman <tal...@mellanox.com>
> ---
> lib/librte_mbuf/rte_mbuf_core.h | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_mbuf/rte_mbuf_core.h b/lib/librte_mbuf/rte_mbuf_core.h
> index b9a59c879..82441555e 100644
> --- a/lib/librte_mbuf/rte_mbuf_core.h
> +++ b/lib/librte_mbuf/rte_mbuf_core.h
> @@ -521,11 +521,12 @@ struct rte_mbuf {
> RTE_STD_C11
> union {
> uint32_t packet_type; /**< L2/L3/L4 and tunnel information. */
> + __extension__
> struct {
> - uint32_t l2_type:4; /**< (Outer) L2 type. */
> - uint32_t l3_type:4; /**< (Outer) L3 type. */
> - uint32_t l4_type:4; /**< (Outer) L4 type. */
> - uint32_t tun_type:4; /**< Tunnel type. */
> + uint8_t l2_type:4; /**< (Outer) L2 type. */
> + uint8_t l3_type:4; /**< (Outer) L3 type. */
> + uint8_t l4_type:4; /**< (Outer) L4 type. */
> + uint8_t tun_type:4; /**< Tunnel type. */
> RTE_STD_C11
> union {
> uint8_t inner_esp_next_proto;
> @@ -541,7 +542,7 @@ struct rte_mbuf {
> /**< Inner L3 type. */
> };
> };
> - uint32_t inner_l4_type:4; /**< Inner L4 type. */
> + uint8_t inner_l4_type:4; /**< Inner L4 type. */
> };
> };
