vdpa_sim_net: vendor satistics

This patch adds support for basic vendor stats that include counters
for tx, rx and cvq.
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221223055548.27810-5-jasowang@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

drivers/vdpa/vdpa_sim/vdpa_sim_net.c

@@ -15,6 +15,7 @@
 #include <linux/etherdevice.h>
 #include <linux/vringh.h>
 #include <linux/vdpa.h>
+#include <net/netlink.h>
 #include <uapi/linux/virtio_net.h>
 #include <uapi/linux/vdpa.h>
 
@@ -37,6 +38,34 @@
 #define VDPASIM_NET_AS_NUM	2
 #define VDPASIM_NET_GROUP_NUM	2
 
+struct vdpasim_dataq_stats {
+	struct u64_stats_sync syncp;
+	u64 pkts;
+	u64 bytes;
+	u64 drops;
+	u64 errors;
+	u64 overruns;
+};
+
+struct vdpasim_cq_stats {
+	struct u64_stats_sync syncp;
+	u64 requests;
+	u64 successes;
+	u64 errors;
+};
+
+struct vdpasim_net{
+	struct vdpasim vdpasim;
+	struct vdpasim_dataq_stats tx_stats;
+	struct vdpasim_dataq_stats rx_stats;
+	struct vdpasim_cq_stats cq_stats;
+};
+
+static struct vdpasim_net *sim_to_net(struct vdpasim *vdpasim)
+{
+	return container_of(vdpasim, struct vdpasim_net, vdpasim);
+}
+
 static void vdpasim_net_complete(struct vdpasim_virtqueue *vq, size_t len)
 {
 	/* Make sure data is wrote before advancing index */
@@ -97,9 +126,11 @@ static virtio_net_ctrl_ack vdpasim_handle_ctrl_mac(struct vdpasim *vdpasim,
 static void vdpasim_handle_cvq(struct vdpasim *vdpasim)
 {
 	struct vdpasim_virtqueue *cvq = &vdpasim->vqs[2];
+	struct vdpasim_net *net = sim_to_net(vdpasim);
 	virtio_net_ctrl_ack status = VIRTIO_NET_ERR;
 	struct virtio_net_ctrl_hdr ctrl;
 	size_t read, write;
+	u64 requests = 0, errors = 0, successes = 0;
 	int err;
 
 	if (!(vdpasim->features & (1ULL << VIRTIO_NET_F_CTRL_VQ)))
@@ -115,10 +146,13 @@ static void vdpasim_handle_cvq(struct vdpasim *vdpasim)
 		if (err <= 0)
 			break;
 
+		++requests;
 		read = vringh_iov_pull_iotlb(&cvq->vring, &cvq->in_iov, &ctrl,
 					     sizeof(ctrl));
-		if (read != sizeof(ctrl))
+		if (read != sizeof(ctrl)) {
+			++errors;
 			break;
+		}
 
 		switch (ctrl.class) {
 		case VIRTIO_NET_CTRL_MAC:
@@ -128,6 +162,11 @@ static void vdpasim_handle_cvq(struct vdpasim *vdpasim)
 			break;
 		}
 
+		if (status == VIRTIO_NET_OK)
+			++successes;
+		else
+			++errors;
+
 		/* Make sure data is wrote before advancing index */
 		smp_wmb();
 
@@ -145,6 +184,12 @@ static void vdpasim_handle_cvq(struct vdpasim *vdpasim)
 			cvq->cb(cvq->private);
 		local_bh_enable();
 	}
+
+	u64_stats_update_begin(&net->cq_stats.syncp);
+	net->cq_stats.requests += requests;
+	net->cq_stats.errors += errors;
+	net->cq_stats.successes += successes;
+	u64_stats_update_end(&net->cq_stats.syncp);
 }
 
 static void vdpasim_net_work(struct work_struct *work)
@@ -152,8 +197,10 @@ static void vdpasim_net_work(struct work_struct *work)
 	struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
 	struct vdpasim_virtqueue *txq = &vdpasim->vqs[1];
 	struct vdpasim_virtqueue *rxq = &vdpasim->vqs[0];
+	struct vdpasim_net *net = sim_to_net(vdpasim);
 	ssize_t read, write;
-	int pkts = 0;
+	u64 tx_pkts = 0, rx_pkts = 0, tx_bytes = 0, rx_bytes = 0;
+	u64 rx_drops = 0, rx_overruns = 0, rx_errors = 0, tx_errors = 0;
 	int err;
 
 	spin_lock(&vdpasim->lock);
@@ -172,14 +219,21 @@ static void vdpasim_net_work(struct work_struct *work)
 	while (true) {
 		err = vringh_getdesc_iotlb(&txq->vring, &txq->out_iov, NULL,
 					   &txq->head, GFP_ATOMIC);
-		if (err <= 0)
+		if (err <= 0) {
+			if (err)
+				++tx_errors;
 			break;
+		}
 
+		++tx_pkts;
 		read = vringh_iov_pull_iotlb(&txq->vring, &txq->out_iov,
 					     vdpasim->buffer,
 					     PAGE_SIZE);
 
+		tx_bytes += read;
+
 		if (!receive_filter(vdpasim, read)) {
+			++rx_drops;
 			vdpasim_net_complete(txq, 0);
 			continue;
 		}
@@ -187,19 +241,25 @@ static void vdpasim_net_work(struct work_struct *work)
 		err = vringh_getdesc_iotlb(&rxq->vring, NULL, &rxq->in_iov,
 					   &rxq->head, GFP_ATOMIC);
 		if (err <= 0) {
+			++rx_overruns;
 			vdpasim_net_complete(txq, 0);
 			break;
 		}
 
 		write = vringh_iov_push_iotlb(&rxq->vring, &rxq->in_iov,
 					      vdpasim->buffer, read);
-		if (write <= 0)
+		if (write <= 0) {
+			++rx_errors;
 			break;
+		}
+
+		++rx_pkts;
+		rx_bytes += write;
 
 		vdpasim_net_complete(txq, 0);
 		vdpasim_net_complete(rxq, write);
 
-		if (++pkts > 4) {
+		if (tx_pkts > 4) {
 			schedule_work(&vdpasim->work);
 			goto out;
 		}
@@ -207,6 +267,145 @@ static void vdpasim_net_work(struct work_struct *work)
 
 out:
 	spin_unlock(&vdpasim->lock);
+
+	u64_stats_update_begin(&net->tx_stats.syncp);
+	net->tx_stats.pkts += tx_pkts;
+	net->tx_stats.bytes += tx_bytes;
+	net->tx_stats.errors += tx_errors;
+	u64_stats_update_end(&net->tx_stats.syncp);
+
+	u64_stats_update_begin(&net->rx_stats.syncp);
+	net->rx_stats.pkts += rx_pkts;
+	net->rx_stats.bytes += rx_bytes;
+	net->rx_stats.drops += rx_drops;
+	net->rx_stats.errors += rx_errors;
+	net->rx_stats.overruns += rx_overruns;
+	u64_stats_update_end(&net->rx_stats.syncp);
+}
+
+static int vdpasim_net_get_stats(struct vdpasim *vdpasim, u16 idx,
+				 struct sk_buff *msg,
+				 struct netlink_ext_ack *extack)
+{
+	struct vdpasim_net *net = sim_to_net(vdpasim);
+	u64 rx_pkts, rx_bytes, rx_errors, rx_overruns, rx_drops;
+	u64 tx_pkts, tx_bytes, tx_errors, tx_drops;
+	u64 cq_requests, cq_successes, cq_errors;
+	unsigned int start;
+	int err = -EMSGSIZE;
+
+	switch(idx) {
+	case 0:
+		do {
+			start = u64_stats_fetch_begin(&net->rx_stats.syncp);
+			rx_pkts = net->rx_stats.pkts;
+			rx_bytes = net->rx_stats.bytes;
+			rx_errors = net->rx_stats.errors;
+			rx_overruns = net->rx_stats.overruns;
+			rx_drops = net->rx_stats.drops;
+		} while (u64_stats_fetch_retry(&net->rx_stats.syncp, start));
+
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+					"rx packets"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      rx_pkts, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "rx bytes"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      rx_bytes, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "rx errors"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      rx_errors, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "rx overrunss"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      rx_overruns, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "rx drops"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      rx_drops, VDPA_ATTR_PAD))
+			break;
+		err = 0;
+		break;
+	case 1:
+		do {
+			start = u64_stats_fetch_begin(&net->tx_stats.syncp);
+			tx_pkts = net->tx_stats.pkts;
+			tx_bytes = net->tx_stats.bytes;
+			tx_errors = net->tx_stats.errors;
+			tx_drops = net->tx_stats.drops;
+		} while (u64_stats_fetch_retry(&net->tx_stats.syncp, start));
+
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "tx packets"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      tx_pkts, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "tx bytes"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      tx_bytes, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "tx errors"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      tx_errors, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "tx drops"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      tx_drops, VDPA_ATTR_PAD))
+			break;
+		err = 0;
+		break;
+	case 2:
+		do {
+			start = u64_stats_fetch_begin(&net->cq_stats.syncp);
+			cq_requests = net->cq_stats.requests;
+			cq_successes = net->cq_stats.successes;
+			cq_errors = net->cq_stats.errors;
+		} while (u64_stats_fetch_retry(&net->cq_stats.syncp, start));
+
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "cvq requests"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      cq_requests, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "cvq successes"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      cq_successes, VDPA_ATTR_PAD))
+			break;
+		if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME,
+				  "cvq errors"))
+			break;
+		if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE,
+				      cq_errors, VDPA_ATTR_PAD))
+			break;
+		err = 0;
+		break;
+	default:
+		err = -EINVAL;
+		break;
+	}
+
+	return err;
 }
 
 static void vdpasim_net_get_config(struct vdpasim *vdpasim, void *config)
@@ -243,6 +442,7 @@ static int vdpasim_net_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 			       const struct vdpa_dev_set_config *config)
 {
 	struct vdpasim_dev_attr dev_attr = {};
+	struct vdpasim_net *net;
 	struct vdpasim *simdev;
 	int ret;
 
@@ -253,10 +453,11 @@ static int vdpasim_net_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	dev_attr.nvqs = VDPASIM_NET_VQ_NUM;
 	dev_attr.ngroups = VDPASIM_NET_GROUP_NUM;
 	dev_attr.nas = VDPASIM_NET_AS_NUM;
-	dev_attr.alloc_size = sizeof(struct vdpasim);
+	dev_attr.alloc_size = sizeof(struct vdpasim_net);
 	dev_attr.config_size = sizeof(struct virtio_net_config);
 	dev_attr.get_config = vdpasim_net_get_config;
 	dev_attr.work_fn = vdpasim_net_work;
+	dev_attr.get_stats = vdpasim_net_get_stats;
 	dev_attr.buffer_size = PAGE_SIZE;
 
 	simdev = vdpasim_create(&dev_attr, config);
@@ -269,6 +470,12 @@ static int vdpasim_net_dev_add(struct vdpa_mgmt_dev *mdev, const char *name,
 	if (ret)
 		goto reg_err;
 
+	net = sim_to_net(simdev);
+
+	u64_stats_init(&net->tx_stats.syncp);
+	u64_stats_init(&net->rx_stats.syncp);
+	u64_stats_init(&net->cq_stats.syncp);
+
 	return 0;
 
 reg_err: