datapath: Clean up code in vport_get_stats().

This should not change behavior.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>

diff --git a/datapath/vport.c b/datapath/vport.c
index 61f0e2a..9ac216c 100644 (file)
--- a/datapath/vport.c
+++ b/datapath/vport.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2010 Nicira Networks.
+ * Copyright (c) 2010, 2011 Nicira Networks.
  * Distributed under the terms of the GNU GPL version 2.
  *
  * Significant portions of this file may be copied from parts of the Linux
@@ -783,6 +783,17 @@ struct kobject *vport_get_kobj(const struct vport *vport)
                return NULL;
 }
 
+static int vport_call_get_stats(struct vport *vport, struct rtnl_link_stats64 *stats)
+{
+       int err;
+
+       rcu_read_lock();
+       err = vport->ops->get_stats(vport, stats);
+       rcu_read_unlock();
+
+       return err;
+}
+
 /**
  *     vport_get_stats - retrieve device stats (for kernel callers)
  *
@@ -793,88 +804,77 @@ struct kobject *vport_get_kobj(const struct vport *vport)
  */
 int vport_get_stats(struct vport *vport, struct rtnl_link_stats64 *stats)
 {
-       struct rtnl_link_stats64 dev_stats;
-       struct rtnl_link_stats64 *dev_statsp = NULL;
-       int err = 0;
+       int i;
 
-       if (vport->ops->get_stats) {
-               if (vport->ops->flags & VPORT_F_GEN_STATS)
-                       dev_statsp = &dev_stats;
-               else
-                       dev_statsp = stats;
+       if (!(vport->ops->flags & VPORT_F_GEN_STATS))
+               return vport_call_get_stats(vport, stats);
 
-               rcu_read_lock();
-               err = vport->ops->get_stats(vport, dev_statsp);
-               rcu_read_unlock();
+       /* We potentially have 3 sources of stats that need to be
+        * combined: those we have collected (split into err_stats and
+        * percpu_stats), offset_stats from set_stats(), and device
+        * error stats from get_stats() (for errors that happen
+        * downstream and therefore aren't reported through our
+        * vport_record_error() function). */
 
-               if (err)
-                       goto out;
-       }
-
-       if (vport->ops->flags & VPORT_F_GEN_STATS) {
-               int i;
+       spin_lock_bh(&vport->stats_lock);
 
-               /* We potentially have 3 sources of stats that need to be
-                * combined: those we have collected (split into err_stats and
-                * percpu_stats), offset_stats from set_stats(), and device
-                * error stats from get_stats() (for errors that happen
-                * downstream and therefore aren't reported through our
-                * vport_record_error() function). */
+       *stats = vport->offset_stats;
 
-               spin_lock_bh(&vport->stats_lock);
+       stats->rx_errors        += vport->err_stats.rx_errors;
+       stats->tx_errors        += vport->err_stats.tx_errors;
+       stats->tx_dropped       += vport->err_stats.tx_dropped;
+       stats->rx_dropped       += vport->err_stats.rx_dropped;
 
-               *stats = vport->offset_stats;
+       spin_unlock_bh(&vport->stats_lock);
 
-               stats->rx_errors        += vport->err_stats.rx_errors;
-               stats->tx_errors        += vport->err_stats.tx_errors;
-               stats->tx_dropped       += vport->err_stats.tx_dropped;
-               stats->rx_dropped       += vport->err_stats.rx_dropped;
-
-               spin_unlock_bh(&vport->stats_lock);
+       if (vport->ops->get_stats) {
+               struct rtnl_link_stats64 dev_stats;
+               int err;
 
-               if (dev_statsp) {
-                       stats->rx_errors           += dev_statsp->rx_errors;
-                       stats->tx_errors           += dev_statsp->tx_errors;
-                       stats->rx_dropped          += dev_statsp->rx_dropped;
-                       stats->tx_dropped          += dev_statsp->tx_dropped;
-                       stats->multicast           += dev_statsp->multicast;
-                       stats->collisions          += dev_statsp->collisions;
-                       stats->rx_length_errors    += dev_statsp->rx_length_errors;
-                       stats->rx_over_errors      += dev_statsp->rx_over_errors;
-                       stats->rx_crc_errors       += dev_statsp->rx_crc_errors;
-                       stats->rx_frame_errors     += dev_statsp->rx_frame_errors;
-                       stats->rx_fifo_errors      += dev_statsp->rx_fifo_errors;
-                       stats->rx_missed_errors    += dev_statsp->rx_missed_errors;
-                       stats->tx_aborted_errors   += dev_statsp->tx_aborted_errors;
-                       stats->tx_carrier_errors   += dev_statsp->tx_carrier_errors;
-                       stats->tx_fifo_errors      += dev_statsp->tx_fifo_errors;
-                       stats->tx_heartbeat_errors += dev_statsp->tx_heartbeat_errors;
-                       stats->tx_window_errors    += dev_statsp->tx_window_errors;
-                       stats->rx_compressed       += dev_statsp->rx_compressed;
-                       stats->tx_compressed       += dev_statsp->tx_compressed;
-               }
+               err = vport_call_get_stats(vport, &dev_stats);
+               if (err)
+                       return err;
+
+               stats->rx_errors           += dev_stats.rx_errors;
+               stats->tx_errors           += dev_stats.tx_errors;
+               stats->rx_dropped          += dev_stats.rx_dropped;
+               stats->tx_dropped          += dev_stats.tx_dropped;
+               stats->multicast           += dev_stats.multicast;
+               stats->collisions          += dev_stats.collisions;
+               stats->rx_length_errors    += dev_stats.rx_length_errors;
+               stats->rx_over_errors      += dev_stats.rx_over_errors;
+               stats->rx_crc_errors       += dev_stats.rx_crc_errors;
+               stats->rx_frame_errors     += dev_stats.rx_frame_errors;
+               stats->rx_fifo_errors      += dev_stats.rx_fifo_errors;
+               stats->rx_missed_errors    += dev_stats.rx_missed_errors;
+               stats->tx_aborted_errors   += dev_stats.tx_aborted_errors;
+               stats->tx_carrier_errors   += dev_stats.tx_carrier_errors;
+               stats->tx_fifo_errors      += dev_stats.tx_fifo_errors;
+               stats->tx_heartbeat_errors += dev_stats.tx_heartbeat_errors;
+               stats->tx_window_errors    += dev_stats.tx_window_errors;
+               stats->rx_compressed       += dev_stats.rx_compressed;
+               stats->tx_compressed       += dev_stats.tx_compressed;
+       }
 
-               for_each_possible_cpu(i) {
-                       const struct vport_percpu_stats *percpu_stats;
-                       struct vport_percpu_stats local_stats;
-                       unsigned seqcount;
+       for_each_possible_cpu(i) {
+               const struct vport_percpu_stats *percpu_stats;
+               struct vport_percpu_stats local_stats;
+               unsigned seqcount;
 
-                       percpu_stats = per_cpu_ptr(vport->percpu_stats, i);
+               percpu_stats = per_cpu_ptr(vport->percpu_stats, i);
 
-                       do {
-                               seqcount = read_seqcount_begin(&percpu_stats->seqlock);
-                               local_stats = *percpu_stats;
-                       } while (read_seqcount_retry(&percpu_stats->seqlock, seqcount));
+               do {
+                       seqcount = read_seqcount_begin(&percpu_stats->seqlock);
+                       local_stats = *percpu_stats;
+               } while (read_seqcount_retry(&percpu_stats->seqlock, seqcount));
 
-                       stats->rx_bytes         += local_stats.rx_bytes;
-                       stats->rx_packets       += local_stats.rx_packets;
-                       stats->tx_bytes         += local_stats.tx_bytes;
-                       stats->tx_packets       += local_stats.tx_packets;
-               }
+               stats->rx_bytes         += local_stats.rx_bytes;
+               stats->rx_packets       += local_stats.rx_packets;
+               stats->tx_bytes         += local_stats.tx_bytes;
+               stats->tx_packets       += local_stats.tx_packets;
        }
 
-out:
-       return err;
+       return 0;
 }
 
 /**