From 0fbd050a7d262b74527a289ae75a33626d1060a8 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 31 Jul 2015 18:25:17 +0200 Subject: [PATCH] virtio_net: add gro capability Straightforward patch to add GRO processing to virtio_net. napi_complete_done() usage allows more aggressive aggregation, opted-in by setting /sys/class/net/xxx/gro_flush_timeout Tested: Setting /sys/class/net/xxx/gro_flush_timeout to 1000 nsec, Rick Jones reported following results. One VM of each on a pair of OpenStack compute nodes with E5-2650Lv3 CPUs and Intel 82599ES-based NICs. So, two "before" and two "after" VMs. The OpenStack compute nodes were running OpenStack Kilo, with VxLAN encapsulation being used through OVS so no GRO coming-up the host stack. The compute nodes themselves were running a 3.14-based kernel. Single-stream netperf, CPU utilizations and thus service demands are based on intra-guest reported CPU. Throughput Mbit/s, bigger is better Min Median Average Max 4.2.0-rc3+ 1364 1686 1678 1938 4.2.0-rc3+flush1k 1824 2269 2275 2647 Send Service Demand, smaller is better Min Median Average Max 4.2.0-rc3+ 0.236 0.558 0.524 0.802 4.2.0-rc3+flush1k 0.176 0.503 0.471 0.738 Receive Service Demand, smaller is better. Min Median Average Max 4.2.0-rc3+ 1.906 2.188 2.191 2.531 4.2.0-rc3+flush1k 0.448 0.529 0.533 0.692 Signed-off-by: Eric Dumazet Tested-by: Rick Jones Cc: "Michael S. Tsirkin" Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller --- drivers/net/virtio_net.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index 7fbca37a1adf..66f08f622dc6 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -518,7 +518,7 @@ static void receive_buf(struct virtnet_info *vi, struct receive_queue *rq, skb_mark_napi_id(skb, &rq->napi); - netif_receive_skb(skb); + napi_gro_receive(&rq->napi, skb); return; frame_err: @@ -756,7 +756,7 @@ static int virtnet_poll(struct napi_struct *napi, int budget) /* Out of packets? */ if (received < budget) { r = virtqueue_enable_cb_prepare(rq->vq); - napi_complete(napi); + napi_complete_done(napi, received); if (unlikely(virtqueue_poll(rq->vq, r)) && napi_schedule_prep(napi)) { virtqueue_disable_cb(rq->vq); -- 2.30.2