On 6/11/20 5:32 AM, Joyce Kong wrote:
> Restrict pointer aliasing to allow the compiler to vectorize loops
> more aggressively.
>
> With this patch, a 9.6% improvement is observed in throughput for
> the virtio-net PVP case, and a 2.4% perf improvement in throughput
> for the virtio-user PVP case. All performance data are measured
> under the 0.001% acceptable packet loss with 2 cores on the vhost
> side.
>
> Signed-off-by: Joyce Kong <joyce.k...@arm.com>
> Reviewed-by: Phil Yang <phil.y...@arm.com>
> ---
> drivers/net/virtio/virtio_rxtx_simple_neon.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
Very nice, we should consider doing the same on other platforms.
> diff --git a/drivers/net/virtio/virtio_rxtx_simple_neon.c
> b/drivers/net/virtio/virtio_rxtx_simple_neon.c
> index 363e2b330..c08dd51fb 100644
> --- a/drivers/net/virtio/virtio_rxtx_simple_neon.c
> +++ b/drivers/net/virtio/virtio_rxtx_simple_neon.c
> @@ -36,8 +36,8 @@
> * - nb_pkts < RTE_VIRTIO_DESC_PER_LOOP, just return no packet
> */
> uint16_t
> -virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
> - uint16_t nb_pkts)
> +virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf
> + **__restrict rx_pkts, uint16_t nb_pkts)
Is __restrict supported by all the compilers?
Wouldn't it be better to introduce a wrapper?
> {
> struct virtnet_rx *rxvq = rx_queue;
> struct virtqueue *vq = rxvq->vq;
>
