Commit 3fa2a1df authored by stephen hemminger's avatar stephen hemminger Committed by David S. Miller
Browse files

virtio-net: per cpu 64 bit stats (v2) 



Use per-cpu variables to maintain 64 bit statistics.

Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@conan.davemloft.net>
parent f984cec6

drivers/net/virtio_net.c

+79 −6
Original line number Diff line number Diff line
@@ -40,6 +40,15 @@ module_param(gso, bool, 0444); 


#define VIRTNET_SEND_COMMAND_SG_MAX    2



struct virtnet_stats {

	struct u64_stats_sync syncp;

	u64 tx_bytes;

	u64 tx_packets;



	u64 rx_bytes;

	u64 rx_packets;

};



struct virtnet_info {

	struct virtio_device *vdev;

	struct virtqueue *rvq, *svq, *cvq;
@@ -56,6 +65,9 @@ struct virtnet_info { 
	/* Host will merge rx buffers for big packets (shake it! shake it!) */

	bool mergeable_rx_bufs;



	/* Active statistics */

	struct virtnet_stats __percpu *stats;



	/* Work struct for refilling if we run low on memory. */

	struct delayed_work refill;
@@ -209,7 +221,6 @@ static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) 
			skb->dev->stats.rx_length_errors++;

			return -EINVAL;

		}



		page = virtqueue_get_buf(vi->rvq, &len);

		if (!page) {

			pr_debug("%s: rx error: %d buffers missing\n",
@@ -217,6 +228,7 @@ static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) 
			skb->dev->stats.rx_length_errors++;

			return -EINVAL;

		}



		if (len > PAGE_SIZE)

			len = PAGE_SIZE;
@@ -230,6 +242,7 @@ static int receive_mergeable(struct virtnet_info *vi, struct sk_buff *skb) 
static void receive_buf(struct net_device *dev, void *buf, unsigned int len)

{

	struct virtnet_info *vi = netdev_priv(dev);

	struct virtnet_stats __percpu *stats = this_cpu_ptr(vi->stats);

	struct sk_buff *skb;

	struct page *page;

	struct skb_vnet_hdr *hdr;
@@ -265,8 +278,11 @@ static void receive_buf(struct net_device *dev, void *buf, unsigned int len) 


	hdr = skb_vnet_hdr(skb);

	skb->truesize += skb->data_len;

	dev->stats.rx_bytes += skb->len;

	dev->stats.rx_packets++;



	u64_stats_update_begin(&stats->syncp);

	stats->rx_bytes += skb->len;

	stats->rx_packets++;

	u64_stats_update_end(&stats->syncp);



	if (hdr->hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {

		pr_debug("Needs csum!\n");
@@ -515,11 +531,16 @@ static unsigned int free_old_xmit_skbs(struct virtnet_info *vi) 
{

	struct sk_buff *skb;

	unsigned int len, tot_sgs = 0;

	struct virtnet_stats __percpu *stats = this_cpu_ptr(vi->stats);



	while ((skb = virtqueue_get_buf(vi->svq, &len)) != NULL) {

		pr_debug("Sent skb %p\n", skb);

		vi->dev->stats.tx_bytes += skb->len;

		vi->dev->stats.tx_packets++;



		u64_stats_update_begin(&stats->syncp);

		stats->tx_bytes += skb->len;

		stats->tx_packets++;

		u64_stats_update_end(&stats->syncp);



		tot_sgs += skb_vnet_hdr(skb)->num_sg;

		dev_kfree_skb_any(skb);

	}
@@ -641,6 +662,40 @@ static int virtnet_set_mac_address(struct net_device *dev, void *p) 
	return 0;

}



static struct rtnl_link_stats64 *virtnet_stats(struct net_device *dev,

					       struct rtnl_link_stats64 *tot)

{

	struct virtnet_info *vi = netdev_priv(dev);

	int cpu;

	unsigned int start;



	for_each_possible_cpu(cpu) {

		struct virtnet_stats __percpu *stats

			= per_cpu_ptr(vi->stats, cpu);

		u64 tpackets, tbytes, rpackets, rbytes;



		do {

			start = u64_stats_fetch_begin(&stats->syncp);

			tpackets = stats->tx_packets;

			tbytes   = stats->tx_bytes;

			rpackets = stats->rx_packets;

			rbytes   = stats->rx_bytes;

		} while (u64_stats_fetch_retry(&stats->syncp, start));



		tot->rx_packets += rpackets;

		tot->tx_packets += tpackets;

		tot->rx_bytes   += rbytes;

		tot->tx_bytes   += tbytes;

	}



	tot->tx_dropped = dev->stats.tx_dropped;

	tot->rx_dropped = dev->stats.rx_dropped;

	tot->rx_length_errors = dev->stats.rx_length_errors;

	tot->rx_frame_errors = dev->stats.rx_frame_errors;



	return tot;

}



#ifdef CONFIG_NET_POLL_CONTROLLER

static void virtnet_netpoll(struct net_device *dev)

{
@@ -650,6 +705,14 @@ static void virtnet_netpoll(struct net_device *dev) 
}

#endif



static void virtnet_free(struct net_device *dev)

{

	struct virtnet_info *vi = netdev_priv(dev);



	free_percpu(vi->stats);

	free_netdev(dev);

}



static int virtnet_open(struct net_device *dev)

{

	struct virtnet_info *vi = netdev_priv(dev);
@@ -835,6 +898,7 @@ static const struct net_device_ops virtnet_netdev = { 
	.ndo_set_mac_address = virtnet_set_mac_address,

	.ndo_set_rx_mode     = virtnet_set_rx_mode,

	.ndo_change_mtu	     = virtnet_change_mtu,

	.ndo_get_stats64     = virtnet_stats,

	.ndo_vlan_rx_add_vid = virtnet_vlan_rx_add_vid,

	.ndo_vlan_rx_kill_vid = virtnet_vlan_rx_kill_vid,

#ifdef CONFIG_NET_POLL_CONTROLLER
@@ -895,6 +959,8 @@ static int virtnet_probe(struct virtio_device *vdev) 
	/* Set up network device as normal. */

	dev->netdev_ops = &virtnet_netdev;

	dev->features = NETIF_F_HIGHDMA;

	dev->destructor = virtnet_free;



	SET_ETHTOOL_OPS(dev, &virtnet_ethtool_ops);

	SET_NETDEV_DEV(dev, &vdev->dev);
@@ -939,6 +1005,11 @@ static int virtnet_probe(struct virtio_device *vdev) 
	vi->vdev = vdev;

	vdev->priv = vi;

	vi->pages = NULL;

	vi->stats = alloc_percpu(struct virtnet_stats);

	err = -ENOMEM;

	if (vi->stats == NULL)

		goto free;



	INIT_DELAYED_WORK(&vi->refill, refill_work);

	sg_init_table(vi->rx_sg, ARRAY_SIZE(vi->rx_sg));

	sg_init_table(vi->tx_sg, ARRAY_SIZE(vi->tx_sg));
@@ -958,7 +1029,7 @@ static int virtnet_probe(struct virtio_device *vdev) 


	err = vdev->config->find_vqs(vdev, nvqs, vqs, callbacks, names);

	if (err)

		goto free;

		goto free_stats;



	vi->rvq = vqs[0];

	vi->svq = vqs[1];
@@ -1003,6 +1074,8 @@ static int virtnet_probe(struct virtio_device *vdev) 
	cancel_delayed_work_sync(&vi->refill);

free_vqs:

	vdev->config->del_vqs(vdev);

free_stats:

	free_percpu(vi->stats);

free:

	free_netdev(dev);

	return err;