netdev: Make 'smap' variable const in netdev_set_qos().

This makes this code more obviously thread-safe.

Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/lib/netdev.c b/lib/netdev.c
index 156984a..434e257 100644 (file)
--- a/lib/netdev.c
+++ b/lib/netdev.c
@@ -1115,7 +1115,7 @@ netdev_set_qos(struct netdev *netdev,
 
     if (class->set_qos) {
         if (!details) {
-            static struct smap empty = SMAP_INITIALIZER(&empty);
+            static const struct smap empty = SMAP_INITIALIZER(&empty);
             details = ∅
         }
         return class->set_qos(netdev, type, details);