1 files changed, 21 insertions, 18 deletions

diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index 4178b4b1d2df..82c10dec1b5a 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -58,7 +58,11 @@
 #include <linux/tcp.h>
 #include <linux/percpu.h>
 
-static DEFINE_PER_CPU(struct net_device_stats, loopback_stats);
+struct pcpu_lstats {
+        unsigned long packets;
+        unsigned long bytes;
+};
+static DEFINE_PER_CPU(struct pcpu_lstats, pcpu_lstats);
 
 #define LOOPBACK_OVERHEAD (128 + MAX_HEADER + 16 + 16)
 
@@ -128,7 +132,7 @@ static void emulate_large_send_offload(struct sk_buff *skb)
  */
 static int loopback_xmit(struct sk_buff *skb, struct net_device *dev)
 {
-        struct net_device_stats *lb_stats;
+        struct pcpu_lstats *lb_stats;
 
         skb_orphan(skb);
 
@@ -149,16 +153,14 @@ static int loopback_xmit(struct sk_buff *skb, struct net_device *dev)
 #endif
         dev->last_rx = jiffies;
 
-        lb_stats = &per_cpu(loopback_stats, get_cpu());
-        lb_stats->rx_bytes += skb->len;
-        lb_stats->tx_bytes = lb_stats->rx_bytes;
-        lb_stats->rx_packets++;
-        lb_stats->tx_packets = lb_stats->rx_packets;
-        put_cpu();
+        /* it's OK to use __get_cpu_var() because BHs are off */
+        lb_stats = &__get_cpu_var(pcpu_lstats);
+        lb_stats->bytes += skb->len;
+        lb_stats->packets++;
 
         netif_rx(skb);
 
-        return(0);
+        return 0;
 }
 
 static struct net_device_stats loopback_stats;
@@ -166,20 +168,21 @@ static struct net_device_stats loopback_stats;
 static struct net_device_stats *get_stats(struct net_device *dev)
 {
         struct net_device_stats *stats = &loopback_stats;
+        unsigned long bytes = 0;
+        unsigned long packets = 0;
         int i;
 
-        memset(stats, 0, sizeof(struct net_device_stats));
-
         for_each_possible_cpu(i) {
-                struct net_device_stats *lb_stats;
+                const struct pcpu_lstats *lb_stats;
 
-                lb_stats = &per_cpu(loopback_stats, i);
-                stats->rx_bytes   += lb_stats->rx_bytes;
-                stats->tx_bytes   += lb_stats->tx_bytes;
-                stats->rx_packets += lb_stats->rx_packets;
-                stats->tx_packets += lb_stats->tx_packets;
+                lb_stats = &per_cpu(pcpu_lstats, i);
+                bytes   += lb_stats->bytes;
+                packets += lb_stats->packets;
         }
-
+        stats->rx_packets = packets;
+        stats->tx_packets = packets;
+        stats->rx_bytes = bytes;
+        stats->tx_bytes = bytes;
         return stats;
 }