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 --- v2 - add stats_sync and per-cpu --- a/drivers/net/xen-netfront.c 2011-06-20 13:34:56.383992463 -0700 +++ b/drivers/net/xen-netfront.c 2011-06-20 13:41:47.207992232 -0700 @@ -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_b { 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_b 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; @@ -867,12 +882,13 @@ static int handle_incoming_queue(struct if (checksum_setup(dev, skb)) { kfree_skb(skb); packets_dropped++; - dev->stats.rx_errors++; 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 +1050,38 @@ static int xennet_change_mtu(struct net_ 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 +1230,7 @@ static const struct net_device_ops xenne .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 +1265,11 @@ static struct net_device * __devinit xen 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 +1288,7 @@ static struct net_device * __devinit xen &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 +1324,8 @@ static struct net_device * __devinit xen 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 +1925,8 @@ static int __devexit xennet_remove(struc xennet_sysfs_delif(info->netdev); + free_percpu(info->stats); + free_netdev(info->netdev); return 0; >>From shemminger@vyatta.com Mon Jun 20 13:36:03 2011 Message-Id: <20110620203603.019928129@vyatta.com> User-Agent: quilt/0.48-1 Date: Mon, 20 Jun 2011 13:35:11 -0700 From: Stephen Hemminger To: davem@davemloft.net Cc: netdev@vger.kernel.org Subject: [PATCH net-next 5/5] ifb: convert to 64 bit stats References: <20110620203506.363818794@vyatta.com> Content-Disposition: inline; filename=ifb-stats64.patch Convert input functional block device to use 64 bit stats. Signed-off-by: Stephen Hemminger --- v2 - add stats_sync --- a/drivers/net/ifb.c 2011-06-09 14:39:25.000000000 -0700 +++ b/drivers/net/ifb.c 2011-06-20 13:30:30.135992612 -0700 @@ -41,8 +41,18 @@ struct ifb_private { struct tasklet_struct ifb_tasklet; int tasklet_pending; + struct sk_buff_head rq; + u64 rx_packets; + u64 rx_bytes; + unsigned long rx_dropped; + struct sk_buff_head tq; + u64 tx_packets; + u64 tx_bytes; + unsigned long tx_dropped; + + struct u64_stats_sync stats_sync; }; static int numifbs = 2; @@ -57,7 +67,6 @@ static void ri_tasklet(unsigned long dev struct net_device *_dev = (struct net_device *)dev; struct ifb_private *dp = netdev_priv(_dev); - struct net_device_stats *stats = &_dev->stats; struct netdev_queue *txq; struct sk_buff *skb; @@ -77,15 +86,18 @@ static void ri_tasklet(unsigned long dev skb->tc_verd = 0; skb->tc_verd = SET_TC_NCLS(skb->tc_verd); - stats->tx_packets++; - stats->tx_bytes +=skb->len; + + u64_stats_update_begin(&dp->stats_sync); + dp->tx_packets++; + dp->tx_bytes += skb->len; + u64_stats_update_end(&dp->stats_sync); rcu_read_lock(); skb->dev = dev_get_by_index_rcu(&init_net, skb->skb_iif); if (!skb->dev) { rcu_read_unlock(); dev_kfree_skb(skb); - stats->tx_dropped++; + dp->tx_dropped++; if (skb_queue_len(&dp->tq) != 0) goto resched; break; @@ -120,9 +132,33 @@ resched: } +static struct rtnl_link_stats64 *ifb_stats64(struct net_device *dev, + struct rtnl_link_stats64 *stats) +{ + struct ifb_private *dp = netdev_priv(dev); + unsigned int start; + + do { + start = u64_stats_fetch_begin_bh(&dp->stats_sync); + + stats->rx_packets = dp->rx_packets; + stats->rx_bytes = dp->rx_bytes; + stats->tx_packets = dp->tx_packets; + stats->tx_bytes = dp->tx_bytes; + + } while (u64_stats_fetch_retry_bh(&dp->stats_sync, start)); + + stats->rx_dropped = dp->rx_dropped; + stats->tx_dropped = dp->tx_dropped; + + return stats; +} + + static const struct net_device_ops ifb_netdev_ops = { .ndo_open = ifb_open, .ndo_stop = ifb_close, + .ndo_get_stats64 = ifb_stats64, .ndo_start_xmit = ifb_xmit, .ndo_validate_addr = eth_validate_addr, }; @@ -153,15 +189,16 @@ static void ifb_setup(struct net_device static netdev_tx_t ifb_xmit(struct sk_buff *skb, struct net_device *dev) { struct ifb_private *dp = netdev_priv(dev); - struct net_device_stats *stats = &dev->stats; u32 from = G_TC_FROM(skb->tc_verd); - stats->rx_packets++; - stats->rx_bytes+=skb->len; + u64_stats_update_begin(&dp->stats_sync); + dp->rx_packets++; + dp->rx_bytes += skb->len; + u64_stats_update_end(&dp->stats_sync); if (!(from & (AT_INGRESS|AT_EGRESS)) || !skb->skb_iif) { dev_kfree_skb(skb); - stats->rx_dropped++; + dp->rx_dropped++; return NETDEV_TX_OK; } -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html