net: minor cleanup in skb_ext_add()

When the extension to be added is already present, the only
skb field we may need to update is 'extensions': we can reorder
the code and avoid a branch.

v1 -> v2:
 - be sure to flag the newly added extension as active

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index e1d8876..37317ff 100644 (file)
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -5666,11 +5666,8 @@ void *skb_ext_add(struct sk_buff *skb, enum skb_ext_id id)
                if (!new)
                        return NULL;
 
-               if (__skb_ext_exist(new, id)) {
-                       if (old != new)
-                               skb->extensions = new;
+               if (__skb_ext_exist(new, id))
                        goto set_active;
-               }
 
                newoff = new->chunks;
        } else {
@@ -5684,8 +5681,8 @@ void *skb_ext_add(struct sk_buff *skb, enum skb_ext_id id)
        newlen = newoff + skb_ext_type_len[id];
        new->chunks = newlen;
        new->offset[id] = newoff;
-       skb->extensions = new;
 set_active:
+       skb->extensions = new;
        skb->active_extensions |= 1 << id;
        return skb_ext_get_ptr(new, id);
 }