vlan: lockless transmit path

vlan is a stacked device, like tunnels. We should use the lockless
mechanism we are using in tunnels and loopback.

This patch completely removes locking in TX path.

tx stat counters are added into existing percpu stat structure, renamed
from vlan_rx_stats to vlan_pcpu_stats.

Note : this partially reverts commit 2e59af3dcbdf (vlan: multiqueue vlan
device)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 6 deletions

diff --git a/net/8021q/vlan.h b/net/8021q/vlan.h
index 4625ba64dfdc..5687c9b95f33 100644
--- a/net/8021q/vlan.h
+++ b/net/8021q/vlan.h
@@ -19,19 +19,25 @@ struct vlan_priority_tci_mapping {
 
 
 /**
- *      struct vlan_rx_stats - VLAN percpu rx stats
+ *      struct vlan_pcpu_stats - VLAN percpu rx/tx stats
  *      @rx_packets: number of received packets
  *      @rx_bytes: number of received bytes
  *      @rx_multicast: number of received multicast packets
+ *      @tx_packets: number of transmitted packets
+ *      @tx_bytes: number of transmitted bytes
  *      @syncp: synchronization point for 64bit counters
- *      @rx_errors: number of errors
+ *      @rx_errors: number of rx errors
+ *      @tx_dropped: number of tx drops
  */
-struct vlan_rx_stats {
+struct vlan_pcpu_stats {
         u64                     rx_packets;
         u64                     rx_bytes;
         u64                     rx_multicast;
+        u64                     tx_packets;
+        u64                     tx_bytes;
         struct u64_stats_sync   syncp;
-        unsigned long           rx_errors;
+        u32                     rx_errors;
+        u32                     tx_dropped;
 };
 
 /**
@@ -45,7 +51,7 @@ struct vlan_rx_stats {
  *      @real_dev: underlying netdevice
  *      @real_dev_addr: address of underlying netdevice
  *      @dent: proc dir entry
- *      @vlan_rx_stats: ptr to percpu rx stats
+ *      @vlan_pcpu_stats: ptr to percpu rx stats
  */
 struct vlan_dev_info {
         unsigned int                            nr_ingress_mappings;
@@ -60,7 +66,7 @@ struct vlan_dev_info {
         unsigned char                           real_dev_addr[ETH_ALEN];
 
         struct proc_dir_entry                   *dent;
-        struct vlan_rx_stats __percpu           *vlan_rx_stats;
+        struct vlan_pcpu_stats __percpu         *vlan_pcpu_stats;
 };
 
 static inline struct vlan_dev_info *vlan_dev_info(const struct net_device *dev)