xen-netfront: use different locks for Rx and Tx stats

[linux-2.6-block.git] / drivers / net / xen-netfront.c

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 22bcb4e12e2a1318fc1802fb3c5ff6b2cb4acf92..d8c10764f13061fd355e0e36abff7c83d3a458a5 100644 (file)
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -88,10 +88,8 @@ struct netfront_cb {
 #define IRQ_NAME_SIZE (QUEUE_NAME_SIZE + 3)
 
 struct netfront_stats {
-       u64                     rx_packets;
-       u64                     tx_packets;
-       u64                     rx_bytes;
-       u64                     tx_bytes;
+       u64                     packets;
+       u64                     bytes;
        struct u64_stats_sync   syncp;
 };
 
@@ -160,7 +158,8 @@ struct netfront_info {
        struct netfront_queue *queues;
 
        /* Statistics */
-       struct netfront_stats __percpu *stats;
+       struct netfront_stats __percpu *rx_stats;
+       struct netfront_stats __percpu *tx_stats;
 
        atomic_t rx_gso_checksum_fixup;
 };
@@ -565,7 +564,7 @@ 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 netfront_stats *tx_stats = this_cpu_ptr(np->tx_stats);
        struct xen_netif_tx_request *tx;
        char *data = skb->data;
        RING_IDX i;
@@ -672,10 +671,10 @@ static int xennet_start_xmit(struct sk_buff *skb, struct net_device *dev)
        if (notify)
                notify_remote_via_irq(queue->tx_irq);
 
-       u64_stats_update_begin(&stats->syncp);
-       stats->tx_bytes += skb->len;
-       stats->tx_packets++;
-       u64_stats_update_end(&stats->syncp);
+       u64_stats_update_begin(&tx_stats->syncp);
+       tx_stats->bytes += skb->len;
+       tx_stats->packets++;
+       u64_stats_update_end(&tx_stats->syncp);
 
        /* Note: It is not safe to access skb after xennet_tx_buf_gc()! */
        xennet_tx_buf_gc(queue);
@@ -931,7 +930,7 @@ static int checksum_setup(struct net_device *dev, struct sk_buff *skb)
 static int handle_incoming_queue(struct netfront_queue *queue,
                                 struct sk_buff_head *rxq)
 {
-       struct netfront_stats *stats = this_cpu_ptr(queue->info->stats);
+       struct netfront_stats *rx_stats = this_cpu_ptr(queue->info->rx_stats);
        int packets_dropped = 0;
        struct sk_buff *skb;
 
@@ -952,10 +951,10 @@ static int handle_incoming_queue(struct netfront_queue *queue,
                        continue;
                }
 
-               u64_stats_update_begin(&stats->syncp);
-               stats->rx_packets++;
-               stats->rx_bytes += skb->len;
-               u64_stats_update_end(&stats->syncp);
+               u64_stats_update_begin(&rx_stats->syncp);
+               rx_stats->packets++;
+               rx_stats->bytes += skb->len;
+               u64_stats_update_end(&rx_stats->syncp);
 
                /* Pass it up. */
                napi_gro_receive(&queue->napi, skb);
@@ -1079,18 +1078,22 @@ static struct rtnl_link_stats64 *xennet_get_stats64(struct net_device *dev,
        int cpu;
 
        for_each_possible_cpu(cpu) {
-               struct netfront_stats *stats = per_cpu_ptr(np->stats, cpu);
+               struct netfront_stats *rx_stats = per_cpu_ptr(np->rx_stats, cpu);
+               struct netfront_stats *tx_stats = per_cpu_ptr(np->tx_stats, cpu);
                u64 rx_packets, rx_bytes, tx_packets, tx_bytes;
                unsigned int start;
 
                do {
-                       start = u64_stats_fetch_begin_irq(&stats->syncp);
+                       start = u64_stats_fetch_begin_irq(&tx_stats->syncp);
+                       tx_packets = tx_stats->packets;
+                       tx_bytes = tx_stats->bytes;
+               } while (u64_stats_fetch_retry_irq(&tx_stats->syncp, start));
 
-                       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_irq(&stats->syncp, start));
+               do {
+                       start = u64_stats_fetch_begin_irq(&rx_stats->syncp);
+                       rx_packets = rx_stats->packets;
+                       rx_bytes = rx_stats->bytes;
+               } while (u64_stats_fetch_retry_irq(&rx_stats->syncp, start));
 
                tot->rx_packets += rx_packets;
                tot->tx_packets += tx_packets;
@@ -1275,6 +1278,15 @@ static const struct net_device_ops xennet_netdev_ops = {
 #endif
 };
 
+static void xennet_free_netdev(struct net_device *netdev)
+{
+       struct netfront_info *np = netdev_priv(netdev);
+
+       free_percpu(np->rx_stats);
+       free_percpu(np->tx_stats);
+       free_netdev(netdev);
+}
+
 static struct net_device *xennet_create_dev(struct xenbus_device *dev)
 {
        int err;
@@ -1295,8 +1307,11 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
        np->queues = NULL;
 
        err = -ENOMEM;
-       np->stats = netdev_alloc_pcpu_stats(struct netfront_stats);
-       if (np->stats == NULL)
+       np->rx_stats = netdev_alloc_pcpu_stats(struct netfront_stats);
+       if (np->rx_stats == NULL)
+               goto exit;
+       np->tx_stats = netdev_alloc_pcpu_stats(struct netfront_stats);
+       if (np->tx_stats == NULL)
                goto exit;
 
        netdev->netdev_ops      = &xennet_netdev_ops;
@@ -1327,7 +1342,7 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
        return netdev;
 
  exit:
-       free_netdev(netdev);
+       xennet_free_netdev(netdev);
        return ERR_PTR(err);
 }
 
@@ -1369,7 +1384,7 @@ static int netfront_probe(struct xenbus_device *dev,
        return 0;
 
  fail:
-       free_netdev(netdev);
+       xennet_free_netdev(netdev);
        dev_set_drvdata(&dev->dev, NULL);
        return err;
 }
@@ -2189,9 +2204,7 @@ static int xennet_remove(struct xenbus_device *dev)
                info->queues = NULL;
        }
 
-       free_percpu(info->stats);
-
-       free_netdev(info->netdev);
+       xennet_free_netdev(info->netdev);
 
        return 0;
 }