[PATCH] tiny af_packet.c cleanup

[Mitchell Blank Jr <mitch@xxxxxxxxxx>]

In both places af_packet.c calls sk_run_filter() it does a "filter =
sk->sk_filter" to store the pointer in a local variable.  However, it
never actually uses this variable for anything -- it always refers to
the filter as sk->sk_filter instead.  Clearly this wasn't intentional.

This patch fixes up both of those cases and cleans up the code a tiny bit.

Patch is versus 2.6.0-test5.

-Mitch

--- linux-2.6.0-test5-VIRGIN/net/packet/af_packet.c     2003-09-08 
12:39:53.000000000 -0700
+++ linux-2.6.0-test5mnb1/net/packet/af_packet.c        2003-09-12 
13:28:53.857179768 -0700
@@ -433,9 +433,9 @@
                struct sk_filter *filter;
 
                bh_lock_sock(sk);
-               if ((filter = sk->sk_filter) != NULL)
-                       res = sk_run_filter(skb, sk->sk_filter->insns,
-                                           sk->sk_filter->len);
+               filter = sk->sk_filter;
+               if (likely(filter != NULL))     /* re-check under lock */
+                       res = sk_run_filter(skb, filter->insns, filter->len);
                bh_unlock_sock(sk);
 
                if (res == 0)
@@ -537,9 +537,9 @@
                struct sk_filter *filter;
 
                bh_lock_sock(sk);
-               if ((filter = sk->sk_filter) != NULL)
-                       res = sk_run_filter(skb, sk->sk_filter->insns,
-                                           sk->sk_filter->len);
+               filter = sk->sk_filter;
+               if (likely(filter != NULL))     /* re-check under lock */
+                       res = sk_run_filter(skb, filter->insns, filter->len);
                bh_unlock_sock(sk);
 
                if (res == 0)