[PATCH] skbuff: remove old NET_CALLER macro

[PATCH] skbuff: remove old NET_CALLER macro

[Stephen Hemminger]

Kill NET_CALLER it causes warnings from sparse and is no longer
necessary.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

diff -urNp -X dontdiff ck-2.6.11/include/linux/skbuff.h net-2.6.11/include/linux/skbuff.h
--- ck-2.6.11/include/linux/skbuff.h	2005-03-02 18:38:38.000000000 +1100
+++ net-2.6.11/include/linux/skbuff.h	2005-04-19 16:59:31.000000000 +1000
@@ -83,12 +83,6 @@
  *	Any questions? No questions, good. 		--ANK
  */
 
-#ifdef __i386__
-#define NET_CALLER(arg) (*(((void **)&arg) - 1))
-#else
-#define NET_CALLER(arg) __builtin_return_address(0)
-#endif
-
 struct net_device;
 
 #ifdef CONFIG_NETFILTER
diff -urNp -X dontdiff ck-2.6.11/net/core/skbuff.c net-2.6.11/net/core/skbuff.c
--- ck-2.6.11/net/core/skbuff.c	2005-04-19 17:07:13.000000000 +1000
+++ net-2.6.11/net/core/skbuff.c	2005-04-19 17:31:38.000000000 +1000
@@ -275,9 +275,10 @@ void kfree_skbmem(struct sk_buff *skb)
 
 void __kfree_skb(struct sk_buff *skb)
 {
-	if (skb->list) {
+	if (unlikely(skb->list)) {
 	 	printk(KERN_WARNING "Warning: kfree_skb passed an skb still "
-		       "on a list (from %p).\n", NET_CALLER(skb));
+		       "on a list (from %p).\n", 
+			__builtin_return_address(0));
 		BUG();
 	}
 
@@ -285,10 +286,11 @@ void __kfree_skb(struct sk_buff *skb)
 #ifdef CONFIG_XFRM
 	secpath_put(skb->sp);
 #endif
-	if(skb->destructor) {
+	if (unlikely(skb->destructor)) {
 		if (in_irq())
 			printk(KERN_WARNING "Warning: kfree_skb on "
-					    "hard IRQ %p\n", NET_CALLER(skb));
+					    "hard IRQ %p\n",
+			__builtin_return_address(0));
 		skb->destructor(skb);
 	}
 #ifdef CONFIG_NETFILTER

Re: [PATCH] skbuff: remove old NET_CALLER macro

[Herbert Xu]

Stephen Hemminger <shemminger@osdl.org> wrote:
> --- ck-2.6.11/net/core/skbuff.c 2005-04-19 17:07:13.000000000 +1000
> +++ net-2.6.11/net/core/skbuff.c        2005-04-19 17:31:38.000000000 +1000
> @@ -275,9 +275,10 @@ void kfree_skbmem(struct sk_buff *skb)
> 
> void __kfree_skb(struct sk_buff *skb)
> {
> -       if (skb->list) {
> +       if (unlikely(skb->list)) {
>                printk(KERN_WARNING "Warning: kfree_skb passed an skb still "
> -                      "on a list (from %p).\n", NET_CALLER(skb));
> +                      "on a list (from %p).\n", 
> +                       __builtin_return_address(0));
>                BUG();

Why not turn this if block into a BUG_ON? The return address will be
printed by BUG anyway.
 
> @@ -285,10 +286,11 @@ void __kfree_skb(struct sk_buff *skb)
> #ifdef CONFIG_XFRM
>        secpath_put(skb->sp);
> #endif
> -       if(skb->destructor) {
> +       if (unlikely(skb->destructor)) {

Are you sure that this is the less common case?

>                if (in_irq())
>                        printk(KERN_WARNING "Warning: kfree_skb on "
> -                                           "hard IRQ %p\n", NET_CALLER(skb));
> +                                           "hard IRQ %p\n",
> +                       __builtin_return_address(0));

Similarly, This can be turned into a WARN_ON.

Cheers,
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Re: [PATCH] skbuff: remove old NET_CALLER macro

[David S. Miller]

On Tue, 19 Apr 2005 18:04:43 +1000
Herbert Xu <herbert@gondor.apana.org.au> wrote:

> Why not turn this if block into a BUG_ON? The return address will be
> printed by BUG anyway.

Also, __builtin_return_address(0) does not work reliably on some
platforms, notably MIPS.  However, you are making a straight
transformation so you're not making things any worse than before.

Eventually, this belongs in linux/compiler.h as "function_caller()"
or something like that.

Re: [PATCH] skbuff: remove old NET_CALLER macro

[Herbert Xu]

On Wed, Apr 20, 2005 at 10:04:57AM +1000, Stephen Hemminger wrote:
> Here is a revised alternative that uses BUG_ON/WARN_ON to eliminate
> NET_CALLER.

Looks good.  Thanks Stephen.
-- 
Visit Openswan at http://www.openswan.org/
Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt