qtnfmac: support 64-bit network interface stats

On 32-bit platforms packet counters are stored in a net_device_stats struct
as unsigned long integers. As a result, after some time of network activity
an overflow takes place in network packet counters. This patch makes use of
new structs for holding interface statistics.

Signed-off-by: Vasily Ulyanov <vulyanov@quantenna.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

diff --git a/drivers/net/wireless/quantenna/qtnfmac/core.c b/drivers/net/wireless/quantenna/qtnfmac/core.c
index ccd982b..c10f24f 100644 (file)
--- a/drivers/net/wireless/quantenna/qtnfmac/core.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/core.c
@@ -119,9 +119,38 @@ qtnf_netdev_hard_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 
 /* Netdev handler for getting stats.
  */
-static struct net_device_stats *qtnf_netdev_get_stats(struct net_device *dev)
+static void qtnf_netdev_get_stats64(struct net_device *ndev,
+                                   struct rtnl_link_stats64 *stats)
 {
-       return &dev->stats;
+       struct qtnf_vif *vif = qtnf_netdev_get_priv(ndev);
+       unsigned int start;
+       int cpu;
+
+       netdev_stats_to_stats64(stats, &ndev->stats);
+
+       if (!vif->stats64)
+               return;
+
+       for_each_possible_cpu(cpu) {
+               struct pcpu_sw_netstats *stats64;
+               u64 rx_packets, rx_bytes;
+               u64 tx_packets, tx_bytes;
+
+               stats64 = per_cpu_ptr(vif->stats64, cpu);
+
+               do {
+                       start = u64_stats_fetch_begin_irq(&stats64->syncp);
+                       rx_packets = stats64->rx_packets;
+                       rx_bytes = stats64->rx_bytes;
+                       tx_packets = stats64->tx_packets;
+                       tx_bytes = stats64->tx_bytes;
+               } while (u64_stats_fetch_retry_irq(&stats64->syncp, start));
+
+               stats->rx_packets += rx_packets;
+               stats->rx_bytes += rx_bytes;
+               stats->tx_packets += tx_packets;
+               stats->tx_bytes += tx_bytes;
+       }
 }
 
 /* Netdev handler for transmission timeout.
@@ -156,7 +185,7 @@ const struct net_device_ops qtnf_netdev_ops = {
        .ndo_stop = qtnf_netdev_close,
        .ndo_start_xmit = qtnf_netdev_hard_start_xmit,
        .ndo_tx_timeout = qtnf_netdev_tx_timeout,
-       .ndo_get_stats = qtnf_netdev_get_stats,
+       .ndo_get_stats64 = qtnf_netdev_get_stats64,
 };
 
 static int qtnf_mac_init_single_band(struct wiphy *wiphy,
@@ -289,6 +318,11 @@ static struct qtnf_wmac *qtnf_core_mac_alloc(struct qtnf_bus *bus,
                qtnf_sta_list_init(&mac->iflist[i].sta_list);
                mutex_init(&mac->mac_lock);
                timer_setup(&mac->scan_timeout, NULL, 0);
+               mac->iflist[i].stats64 =
+                       netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
+               if (!mac->iflist[i].stats64)
+                       pr_warn("VIF%u.%u: per cpu stats allocation failed\n",
+                               macid, i);
        }
 
        qtnf_mac_init_primary_intf(mac);
@@ -364,6 +398,7 @@ 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)
@@ -643,6 +678,46 @@ 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);
+
 MODULE_AUTHOR("Quantenna Communications");
 MODULE_DESCRIPTION("Quantenna 802.11 wireless LAN FullMAC driver.");
 MODULE_LICENSE("GPL");

diff --git a/drivers/net/wireless/quantenna/qtnfmac/core.h b/drivers/net/wireless/quantenna/qtnfmac/core.h
index c109001..09fa5d2 100644 (file)
--- a/drivers/net/wireless/quantenna/qtnfmac/core.h
+++ b/drivers/net/wireless/quantenna/qtnfmac/core.h
@@ -89,6 +89,8 @@ 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 {
@@ -157,6 +159,9 @@ int qtnf_cmd_send_get_phy_params(struct qtnf_wmac *mac);
 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);
 
 void qtnf_netdev_updown(struct net_device *ndev, bool up);

diff --git a/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c b/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
index 7e48762..6f61909 100644 (file)
--- a/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
+++ b/drivers/net/wireless/quantenna/qtnfmac/pearl/pcie.c
@@ -615,8 +615,7 @@ static void qtnf_pcie_data_tx_reclaim(struct qtnf_pcie_bus_priv *priv)
                                         PCI_DMA_TODEVICE);
 
                        if (skb->dev) {
-                               skb->dev->stats.tx_packets++;
-                               skb->dev->stats.tx_bytes += skb->len;
+                               qtnf_update_tx_stats(skb->dev, skb);
                                if (unlikely(priv->tx_stopped)) {
                                        qtnf_wake_all_queues(skb->dev);
                                        priv->tx_stopped = 0;
@@ -855,9 +854,7 @@ static int qtnf_rx_poll(struct napi_struct *napi, int budget)
                        skb_put(skb, psize);
                        ndev = qtnf_classify_skb(bus, skb);
                        if (likely(ndev)) {
-                               ndev->stats.rx_packets++;
-                               ndev->stats.rx_bytes += skb->len;
-
+                               qtnf_update_rx_stats(ndev, skb);
                                skb->protocol = eth_type_trans(skb, ndev);
                                napi_gro_receive(napi, skb);
                        } else {