Commit 3889a803 authored by Paolo Abeni's avatar Paolo Abeni Committed by David S. Miller
Browse files

net: factor out a helper to decrement the skb refcount 



The same code is replicated in 3 different places; move it to a
common helper.

Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
Acked-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 78d61022

include/linux/skbuff.h

+13 −0
Original line number Diff line number Diff line
@@ -867,6 +867,19 @@ static inline unsigned int skb_napi_id(const struct sk_buff *skb) 
#endif

}



/* decrement the reference count and return true if we can free the skb */

static inline bool skb_unref(struct sk_buff *skb)

{

	if (unlikely(!skb))

		return false;

	if (likely(atomic_read(&skb->users) == 1))

		smp_rmb();

	else if (likely(!atomic_dec_and_test(&skb->users)))

		return false;



	return true;

}



void kfree_skb(struct sk_buff *skb);

void kfree_skb_list(struct sk_buff *segs);

void skb_tx_error(struct sk_buff *skb);

net/core/datagram.c

+1 −3
Original line number Diff line number Diff line
@@ -330,9 +330,7 @@ void __skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb, int len) 
{

	bool slow;



	if (likely(atomic_read(&skb->users) == 1))

		smp_rmb();

	else if (likely(!atomic_dec_and_test(&skb->users))) {

	if (!skb_unref(skb)) {

		sk_peek_offset_bwd(sk, len);

		return;

	}

net/core/skbuff.c

+4 −10
Original line number Diff line number Diff line
@@ -694,12 +694,9 @@ EXPORT_SYMBOL(__kfree_skb); 
 */

void kfree_skb(struct sk_buff *skb)

{

	if (unlikely(!skb))

		return;

	if (likely(atomic_read(&skb->users) == 1))

		smp_rmb();

	else if (likely(!atomic_dec_and_test(&skb->users)))

	if (!skb_unref(skb))

		return;



	trace_kfree_skb(skb, __builtin_return_address(0));

	__kfree_skb(skb);

}
@@ -746,12 +743,9 @@ EXPORT_SYMBOL(skb_tx_error); 
 */

void consume_skb(struct sk_buff *skb)

{

	if (unlikely(!skb))

		return;

	if (likely(atomic_read(&skb->users) == 1))

		smp_rmb();

	else if (likely(!atomic_dec_and_test(&skb->users)))

	if (!skb_unref(skb))

		return;



	trace_consume_skb(skb);

	__kfree_skb(skb);

}