batman-adv: don't switch byte order too often if not needed

If possible, operations like ntohs/ntohl should not be
performed too often. Use a variable to locally store the
converted value and then use it.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 46278bfb8fdb..a89e812963e5 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -1135,6 +1135,7 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
         int hdr_size = sizeof(*bcast_packet);
         int ret = NET_RX_DROP;
         int32_t seq_diff;
+        uint32_t seqno;
 
         /* drop packet if it has not necessary minimum size */
         if (unlikely(!pskb_may_pull(skb, hdr_size)))
@@ -1170,12 +1171,13 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
 
         spin_lock_bh(&orig_node->bcast_seqno_lock);
 
+        seqno = ntohl(bcast_packet->seqno);
         /* check whether the packet is a duplicate */
         if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
-                            ntohl(bcast_packet->seqno)))
+                            seqno))
                 goto spin_unlock;
 
-        seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno;
+        seq_diff = seqno - orig_node->last_bcast_seqno;
 
         /* check whether the packet is old and the host just restarted. */
         if (batadv_window_protected(bat_priv, seq_diff,
@@ -1186,7 +1188,7 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
          * if required.
          */
         if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
-                orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno);
+                orig_node->last_bcast_seqno = seqno;
 
         spin_unlock_bh(&orig_node->bcast_seqno_lock);