qtnfmac: switch to core handling of rx/tx byte/packet counters

Use netdev->tstats instead of a member of qtnf_vif for storing a pointer
to the per-cpu counters. This allows us to use core functionality for
statistics handling.
The driver sets netdev->needs_free_netdev, therefore freeing the per-cpu
counters at the right point in time is a little bit tricky. Best option
seems to be to use the ndo_init/ndo_uninit callbacks.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Acked-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/wireless/quantenna/qtnfmac/core.c

@@ -126,28 +126,13 @@ qtnf_netdev_hard_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 
 	if (unlikely(skb->protocol == htons(ETH_P_PAE))) {
 		qtnf_packet_send_hi_pri(skb);
-		qtnf_update_tx_stats(ndev, skb);
+		dev_sw_netstats_tx_add(ndev, 1, skb->len);
 		return NETDEV_TX_OK;
 	}
 
 	return qtnf_bus_data_tx(mac->bus, skb, mac->macid, vif->vifid);
 }
 
-/* Netdev handler for getting stats.
- */
-static void qtnf_netdev_get_stats64(struct net_device *ndev,
-				    struct rtnl_link_stats64 *stats)
-{
-	struct qtnf_vif *vif = qtnf_netdev_get_priv(ndev);
-
-	netdev_stats_to_stats64(stats, &ndev->stats);
-
-	if (!vif->stats64)
-		return;
-
-	dev_fetch_sw_netstats(stats, vif->stats64);
-}
-
 /* Netdev handler for transmission timeout.
  */
 static void qtnf_netdev_tx_timeout(struct net_device *ndev, unsigned int txqueue)
@@ -211,13 +196,27 @@ static int qtnf_netdev_port_parent_id(struct net_device *ndev,
 	return 0;
 }
 
+static int qtnf_netdev_alloc_pcpu_stats(struct net_device *dev)
+{
+	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
+
+	return dev->tstats ? 0 : -ENOMEM;
+}
+
+static void qtnf_netdev_free_pcpu_stats(struct net_device *dev)
+{
+	free_percpu(dev->tstats);
+}
+
 /* Network device ops handlers */
 const struct net_device_ops qtnf_netdev_ops = {
+	.ndo_init = qtnf_netdev_alloc_pcpu_stats,
+	.ndo_uninit = qtnf_netdev_free_pcpu_stats,
 	.ndo_open = qtnf_netdev_open,
 	.ndo_stop = qtnf_netdev_close,
 	.ndo_start_xmit = qtnf_netdev_hard_start_xmit,
 	.ndo_tx_timeout = qtnf_netdev_tx_timeout,
-	.ndo_get_stats64 = qtnf_netdev_get_stats64,
+	.ndo_get_stats64 = dev_get_tstats64,
 	.ndo_set_mac_address = qtnf_netdev_set_mac_address,
 	.ndo_get_port_parent_id = qtnf_netdev_port_parent_id,
 };
@@ -448,10 +447,6 @@ static struct qtnf_wmac *qtnf_core_mac_alloc(struct qtnf_bus *bus,
 		qtnf_sta_list_init(&vif->sta_list);
 		INIT_WORK(&vif->high_pri_tx_work, qtnf_vif_send_data_high_pri);
 		skb_queue_head_init(&vif->high_pri_tx_queue);
-		vif->stats64 = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
-		if (!vif->stats64)
-			pr_warn("VIF%u.%u: per cpu stats allocation failed\n",
-				macid, i);
 	}
 
 	qtnf_mac_init_primary_intf(mac);
@@ -531,7 +526,6 @@ static void qtnf_core_mac_detach(struct qtnf_bus *bus, unsigned int macid)
 		}
 		rtnl_unlock();
 		qtnf_sta_list_free(&vif->sta_list);
-		free_percpu(vif->stats64);
 	}
 
 	if (mac->wiphy_registered)
@@ -924,46 +918,6 @@ void qtnf_wake_all_queues(struct net_device *ndev)
 }
 EXPORT_SYMBOL_GPL(qtnf_wake_all_queues);
 
-void qtnf_update_rx_stats(struct net_device *ndev, const struct sk_buff *skb)
-{
-	struct qtnf_vif *vif = qtnf_netdev_get_priv(ndev);
-	struct pcpu_sw_netstats *stats64;
-
-	if (unlikely(!vif || !vif->stats64)) {
-		ndev->stats.rx_packets++;
-		ndev->stats.rx_bytes += skb->len;
-		return;
-	}
-
-	stats64 = this_cpu_ptr(vif->stats64);
-
-	u64_stats_update_begin(&stats64->syncp);
-	stats64->rx_packets++;
-	stats64->rx_bytes += skb->len;
-	u64_stats_update_end(&stats64->syncp);
-}
-EXPORT_SYMBOL_GPL(qtnf_update_rx_stats);
-
-void qtnf_update_tx_stats(struct net_device *ndev, const struct sk_buff *skb)
-{
-	struct qtnf_vif *vif = qtnf_netdev_get_priv(ndev);
-	struct pcpu_sw_netstats *stats64;
-
-	if (unlikely(!vif || !vif->stats64)) {
-		ndev->stats.tx_packets++;
-		ndev->stats.tx_bytes += skb->len;
-		return;
-	}
-
-	stats64 = this_cpu_ptr(vif->stats64);
-
-	u64_stats_update_begin(&stats64->syncp);
-	stats64->tx_packets++;
-	stats64->tx_bytes += skb->len;
-	u64_stats_update_end(&stats64->syncp);
-}
-EXPORT_SYMBOL_GPL(qtnf_update_tx_stats);
-
 struct dentry *qtnf_get_debugfs_dir(void)
 {
 	return qtnf_debugfs_dir;

drivers/net/wireless/quantenna/qtnfmac/core.h

@@ -70,8 +70,6 @@ struct qtnf_vif {
 	struct qtnf_sta_list sta_list;
 	unsigned long cons_tx_timeout_cnt;
 	int generation;
-
-	struct pcpu_sw_netstats __percpu *stats64;
 };
 
 struct qtnf_mac_info {
@@ -139,8 +137,6 @@ int qtnf_cmd_send_update_phy_params(struct qtnf_wmac *mac, u32 changed);
 struct qtnf_wmac *qtnf_core_get_mac(const struct qtnf_bus *bus, u8 macid);
 struct net_device *qtnf_classify_skb(struct qtnf_bus *bus, struct sk_buff *skb);
 void qtnf_wake_all_queues(struct net_device *ndev);
-void qtnf_update_rx_stats(struct net_device *ndev, const struct sk_buff *skb);
-void qtnf_update_tx_stats(struct net_device *ndev, const struct sk_buff *skb);
 
 void qtnf_virtual_intf_cleanup(struct net_device *ndev);
 

drivers/net/wireless/quantenna/qtnfmac/pcie/pearl_pcie.c

@@ -489,7 +489,7 @@ static void qtnf_pearl_data_tx_reclaim(struct qtnf_pcie_pearl_state *ps)
 					 PCI_DMA_TODEVICE);
 
 			if (skb->dev) {
-				qtnf_update_tx_stats(skb->dev, skb);
+				dev_sw_netstats_tx_add(skb->dev, 1, skb->len);
 				if (unlikely(priv->tx_stopped)) {
 					qtnf_wake_all_queues(skb->dev);
 					priv->tx_stopped = 0;
@@ -756,7 +756,7 @@ static int qtnf_pcie_pearl_rx_poll(struct napi_struct *napi, int budget)
 			skb_put(skb, psize);
 			ndev = qtnf_classify_skb(bus, skb);
 			if (likely(ndev)) {
-				qtnf_update_rx_stats(ndev, skb);
+				dev_sw_netstats_rx_add(ndev, skb->len);
 				skb->protocol = eth_type_trans(skb, ndev);
 				napi_gro_receive(napi, skb);
 			} else {

drivers/net/wireless/quantenna/qtnfmac/pcie/topaz_pcie.c

@@ -418,7 +418,7 @@ static void qtnf_topaz_data_tx_reclaim(struct qtnf_pcie_topaz_state *ts)
 					 PCI_DMA_TODEVICE);
 
 			if (skb->dev) {
-				qtnf_update_tx_stats(skb->dev, skb);
+				dev_sw_netstats_tx_add(skb->dev, 1, skb->len);
 				if (unlikely(priv->tx_stopped)) {
 					qtnf_wake_all_queues(skb->dev);
 					priv->tx_stopped = 0;
@@ -662,7 +662,7 @@ static int qtnf_topaz_rx_poll(struct napi_struct *napi, int budget)
 			skb_put(skb, psize);
 			ndev = qtnf_classify_skb(bus, skb);
 			if (likely(ndev)) {
-				qtnf_update_rx_stats(ndev, skb);
+				dev_sw_netstats_rx_add(ndev, skb->len);
 				skb->protocol = eth_type_trans(skb, ndev);
 				netif_receive_skb(skb);
 			} else {