[dpdk-stable] [PATCH 1/2] net/mlx5: fix Rx CQ doorbell synchronization on aarch64

[Matan Azrad]

From: Phil Yang 
> Subject: [PATCH 1/2] net/mlx5: fix Rx CQ doorbell synchronization on aarch64
> 
> The Rx completion queue doorbell field needs to be updated after the last
> CQE decompressed. For the weaker memory model processors, the compiler
> barrier is not sufficient to guarantee the order of these operations, so use
> the coherent I/O memory barrier to make sure these fields are updated in
> order.
> 
> Fixes: 570acdb1da8a ("net/mlx5: add vectorized Rx/Tx burst for ARM")
> Cc: stable at dpdk.org
> 
> Suggested-by: Gavin Hu <gavin.hu at arm.com>
> Signed-off-by: Phil Yang <phil.yang at arm.com>
> Reviewed-by: Gavin Hu <gavin.hu at arm.com>
Acked-by: Matan Azrad <matan at mellanox.com>