[PATCH net-next] net: skbuff: don't zero tc members when freeing skb

[PATCH net-next] net: skbuff: don't zero tc members when freeing skb

[Florian Westphal]

Not needed, only four cases:
 - kfree_skb (or one of its aliases).
   Don't need to zero, memory will be freed.
 - kfree_skb_partial and head was stolen:  memory will be freed.
 - skb_morph:  The skb header fields (including tc ones) will be
   copied over from the 'to-be-morphed' skb right after
   skb_release_head_state returns.
 - skb_segment:  Same as before, all the skb header
   fields are copied over from the original skb right away.

Signed-off-by: Florian Westphal <fw@strlen.de>
---
 net/core/skbuff.c | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index ae13ef6..8e20bfa 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -677,13 +677,6 @@ static void skb_release_head_state(struct sk_buff *skb)
 #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
 	nf_bridge_put(skb->nf_bridge);
 #endif
-/* XXX: IS this still necessary? - JHS */
-#ifdef CONFIG_NET_SCHED
-	skb->tc_index = 0;
-#ifdef CONFIG_NET_CLS_ACT
-	skb->tc_verd = 0;
-#endif
-#endif
 }
 
 /* Free everything but the sk_buff shell. */
-- 
2.0.5

Re: [PATCH net-next] net: skbuff: don't zero tc members when freeing skb

[David Miller]

From: Florian Westphal <fw@strlen.de>
Date: Wed, 31 Dec 2014 13:33:41 +0100

> Not needed, only four cases:
>  - kfree_skb (or one of its aliases).
>    Don't need to zero, memory will be freed.
>  - kfree_skb_partial and head was stolen:  memory will be freed.
>  - skb_morph:  The skb header fields (including tc ones) will be
>    copied over from the 'to-be-morphed' skb right after
>    skb_release_head_state returns.
>  - skb_segment:  Same as before, all the skb header
>    fields are copied over from the original skb right away.
> 
> Signed-off-by: Florian Westphal <fw@strlen.de>

Agreed, applied, thanks Florian.