From 5a490510ba5fce8a10746525357a297f8f076bb1 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 22 Apr 2015 17:10:38 +0200 Subject: [PATCH] mac80211: use per-CPU TX/RX statistics This isn't all that relevant for RX right now, but TX can be concurrent due to multi-queue and the accounting is therefore broken. Use the standard per-CPU statistics to avoid this. Signed-off-by: Johannes Berg --- net/mac80211/iface.c | 45 +++++++++++++++++++++++++++++++++++++++++++- net/mac80211/rx.c | 21 ++++++++++++++------- net/mac80211/tx.c | 16 ++++++++++++---- 3 files changed, 70 insertions(+), 12 deletions(-) diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 7791a08a560a..dc2d7133c4f6 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -1094,6 +1094,35 @@ static u16 ieee80211_netdev_select_queue(struct net_device *dev, return ieee80211_select_queue(IEEE80211_DEV_TO_SUB_IF(dev), skb); } +static struct rtnl_link_stats64 * +ieee80211_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) +{ + int i; + + for_each_possible_cpu(i) { + const struct pcpu_sw_netstats *tstats; + u64 rx_packets, rx_bytes, tx_packets, tx_bytes; + unsigned int start; + + tstats = per_cpu_ptr(dev->tstats, i); + + do { + start = u64_stats_fetch_begin_irq(&tstats->syncp); + rx_packets = tstats->rx_packets; + tx_packets = tstats->tx_packets; + rx_bytes = tstats->rx_bytes; + tx_bytes = tstats->tx_bytes; + } while (u64_stats_fetch_retry_irq(&tstats->syncp, start)); + + stats->rx_packets += rx_packets; + stats->tx_packets += tx_packets; + stats->rx_bytes += rx_bytes; + stats->tx_bytes += tx_bytes; + } + + return stats; +} + static const struct net_device_ops ieee80211_dataif_ops = { .ndo_open = ieee80211_open, .ndo_stop = ieee80211_stop, @@ -1103,6 +1132,7 @@ static const struct net_device_ops ieee80211_dataif_ops = { .ndo_change_mtu = ieee80211_change_mtu, .ndo_set_mac_address = ieee80211_change_mac, .ndo_select_queue = ieee80211_netdev_select_queue, + .ndo_get_stats64 = ieee80211_get_stats64, }; static u16 ieee80211_monitor_select_queue(struct net_device *dev, @@ -1136,14 +1166,21 @@ static const struct net_device_ops ieee80211_monitorif_ops = { .ndo_change_mtu = ieee80211_change_mtu, .ndo_set_mac_address = ieee80211_change_mac, .ndo_select_queue = ieee80211_monitor_select_queue, + .ndo_get_stats64 = ieee80211_get_stats64, }; +static void ieee80211_if_free(struct net_device *dev) +{ + free_percpu(dev->tstats); + free_netdev(dev); +} + static void ieee80211_if_setup(struct net_device *dev) { ether_setup(dev); dev->priv_flags &= ~IFF_TX_SKB_SHARING; dev->netdev_ops = &ieee80211_dataif_ops; - dev->destructor = free_netdev; + dev->destructor = ieee80211_if_free; } static void ieee80211_iface_work(struct work_struct *work) @@ -1684,6 +1721,12 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name, return -ENOMEM; dev_net_set(ndev, wiphy_net(local->hw.wiphy)); + ndev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats); + if (!ndev->tstats) { + free_netdev(ndev); + return -ENOMEM; + } + ndev->needed_headroom = local->tx_headroom + 4*6 /* four MAC addresses */ + 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */ diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 11dbbc576491..b69a071d7679 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -32,6 +32,16 @@ #include "wme.h" #include "rate.h" +static inline void ieee80211_rx_stats(struct net_device *dev, u32 len) +{ + struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats); + + u64_stats_update_begin(&tstats->syncp); + tstats->rx_packets++; + tstats->rx_bytes += len; + u64_stats_update_end(&tstats->syncp); +} + /* * monitor mode reception * @@ -529,8 +539,7 @@ ieee80211_rx_monitor(struct ieee80211_local *local, struct sk_buff *origskb, } prev_dev = sdata->dev; - sdata->dev->stats.rx_packets++; - sdata->dev->stats.rx_bytes += skb->len; + ieee80211_rx_stats(sdata->dev, skb->len); } if (prev_dev) { @@ -2036,12 +2045,11 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx) struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data; struct sta_info *dsta; - dev->stats.rx_packets++; - dev->stats.rx_bytes += rx->skb->len; - skb = rx->skb; xmit_skb = NULL; + ieee80211_rx_stats(dev, skb->len); + if ((sdata->vif.type == NL80211_IFTYPE_AP || sdata->vif.type == NL80211_IFTYPE_AP_VLAN) && !(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) && @@ -3045,8 +3053,7 @@ static void ieee80211_rx_cooked_monitor(struct ieee80211_rx_data *rx, } prev_dev = sdata->dev; - sdata->dev->stats.rx_packets++; - sdata->dev->stats.rx_bytes += skb->len; + ieee80211_rx_stats(sdata->dev, skb->len); } if (prev_dev) { diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 83e3261dbf67..745fdf5c2722 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -37,6 +37,16 @@ /* misc utils */ +static inline void ieee80211_tx_stats(struct net_device *dev, u32 len) +{ + struct pcpu_sw_netstats *tstats = this_cpu_ptr(dev->tstats); + + u64_stats_update_begin(&tstats->syncp); + tstats->tx_packets++; + tstats->tx_bytes += len; + u64_stats_update_end(&tstats->syncp); +} + static __le16 ieee80211_duration(struct ieee80211_tx_data *tx, struct sk_buff *skb, int group_addr, int next_frag_len) @@ -2727,8 +2737,7 @@ static bool ieee80211_xmit_fast(struct ieee80211_sub_if_data *sdata, return true; } - dev->stats.tx_packets++; - dev->stats.tx_bytes += skb->len + extra_head; + ieee80211_tx_stats(dev, skb->len + extra_head); /* will not be crypto-handled beyond what we do here, so use false * as the may-encrypt argument for the resize to not account for @@ -2909,8 +2918,7 @@ void __ieee80211_subif_start_xmit(struct sk_buff *skb, if (IS_ERR(skb)) goto out; - dev->stats.tx_packets++; - dev->stats.tx_bytes += skb->len; + ieee80211_tx_stats(dev, skb->len); ieee80211_xmit(sdata, sta, skb); }