From e00f85bec0a9924eb517ccd126ddbb9787068f53 Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Tue, 21 Jun 2011 05:35:31 +0000 Subject: xen: convert to 64 bit stats interface Convert xen driver to 64 bit statistics interface. Use stats_sync to ensure that 64 bit update is read atomically on 32 bit platform. Put hot statistics into per-cpu table. Signed-off-by: Stephen Hemminger Acked-by: Ian Campbell Signed-off-by: David S. Miller --- drivers/net/xen-netfront.c | 69 ++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 64 insertions(+), 5 deletions(-) (limited to 'drivers/net/xen-netfront.c') diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index d29365a232a..d7c8a98daff 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -70,6 +70,14 @@ struct netfront_cb { #define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) #define TX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256) +struct netfront_stats { + u64 rx_packets; + u64 tx_packets; + u64 rx_bytes; + u64 tx_bytes; + struct u64_stats_sync syncp; +}; + struct netfront_info { struct list_head list; struct net_device *netdev; @@ -122,6 +130,8 @@ struct netfront_info { struct mmu_update rx_mmu[NET_RX_RING_SIZE]; /* Statistics */ + struct netfront_stats __percpu *stats; + unsigned long rx_gso_checksum_fixup; }; @@ -468,6 +478,7 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) { unsigned short id; struct netfront_info *np = netdev_priv(dev); + struct netfront_stats *stats = this_cpu_ptr(np->stats); struct xen_netif_tx_request *tx; struct xen_netif_extra_info *extra; char *data = skb->data; @@ -552,8 +563,10 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev) if (notify) notify_remote_via_irq(np->netdev->irq); - dev->stats.tx_bytes += skb->len; - dev->stats.tx_packets++; + u64_stats_update_begin(&stats->syncp); + stats->tx_bytes += skb->len; + stats->tx_packets++; + u64_stats_update_end(&stats->syncp); /* Note: It is not safe to access skb after xennet_tx_buf_gc()! */ xennet_tx_buf_gc(dev); @@ -847,6 +860,8 @@ out: static int handle_incoming_queue(struct net_device *dev, struct sk_buff_head *rxq) { + struct netfront_info *np = netdev_priv(dev); + struct netfront_stats *stats = this_cpu_ptr(np->stats); int packets_dropped = 0; struct sk_buff *skb; @@ -871,8 +886,10 @@ static int handle_incoming_queue(struct net_device *dev, continue; } - dev->stats.rx_packets++; - dev->stats.rx_bytes += skb->len; + u64_stats_update_begin(&stats->syncp); + stats->rx_packets++; + stats->rx_bytes += skb->len; + u64_stats_update_end(&stats->syncp); /* Pass it up. */ netif_receive_skb(skb); @@ -1034,6 +1051,38 @@ static int xennet_change_mtu(struct net_device *dev, int mtu) return 0; } +static struct rtnl_link_stats64 *xennet_get_stats64(struct net_device *dev, + struct rtnl_link_stats64 *tot) +{ + struct netfront_info *np = netdev_priv(dev); + int cpu; + + for_each_possible_cpu(cpu) { + struct netfront_stats *stats = per_cpu_ptr(np->stats, cpu); + u64 rx_packets, rx_bytes, tx_packets, tx_bytes; + unsigned int start; + + do { + start = u64_stats_fetch_begin_bh(&stats->syncp); + + rx_packets = stats->rx_packets; + tx_packets = stats->tx_packets; + rx_bytes = stats->rx_bytes; + tx_bytes = stats->tx_bytes; + } while (u64_stats_fetch_retry_bh(&stats->syncp, start)); + + tot->rx_packets += rx_packets; + tot->tx_packets += tx_packets; + tot->rx_bytes += rx_bytes; + tot->tx_bytes += tx_bytes; + } + + tot->rx_errors = dev->stats.rx_errors; + tot->tx_dropped = dev->stats.tx_dropped; + + return tot; +} + static void xennet_release_tx_bufs(struct netfront_info *np) { struct sk_buff *skb; @@ -1182,6 +1231,7 @@ static const struct net_device_ops xennet_netdev_ops = { .ndo_stop = xennet_close, .ndo_start_xmit = xennet_start_xmit, .ndo_change_mtu = xennet_change_mtu, + .ndo_get_stats64 = xennet_get_stats64, .ndo_set_mac_address = eth_mac_addr, .ndo_validate_addr = eth_validate_addr, .ndo_fix_features = xennet_fix_features, @@ -1216,6 +1266,11 @@ static struct net_device * __devinit xennet_create_dev(struct xenbus_device *dev np->rx_refill_timer.data = (unsigned long)netdev; np->rx_refill_timer.function = rx_refill_timeout; + err = -ENOMEM; + np->stats = alloc_percpu(struct netfront_stats); + if (np->stats == NULL) + goto exit; + /* Initialise tx_skbs as a free chain containing every entry. */ np->tx_skb_freelist = 0; for (i = 0; i < NET_TX_RING_SIZE; i++) { @@ -1234,7 +1289,7 @@ static struct net_device * __devinit xennet_create_dev(struct xenbus_device *dev &np->gref_tx_head) < 0) { printk(KERN_ALERT "#### netfront can't alloc tx grant refs\n"); err = -ENOMEM; - goto exit; + goto exit_free_stats; } /* A grant for every rx ring slot */ if (gnttab_alloc_grant_references(RX_MAX_TARGET, @@ -1270,6 +1325,8 @@ static struct net_device * __devinit xennet_create_dev(struct xenbus_device *dev exit_free_tx: gnttab_free_grant_references(np->gref_tx_head); + exit_free_stats: + free_percpu(np->stats); exit: free_netdev(netdev); return ERR_PTR(err); @@ -1869,6 +1926,8 @@ static int __devexit xennet_remove(struct xenbus_device *dev) xennet_sysfs_delif(info->netdev); + free_percpu(info->stats); + free_netdev(info->netdev); return 0; -- cgit v1.2.3-18-g5258