diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 1f659e8c2b888677f8a92dc2c0e2d1562ae856f1..1fbab2ae613c6338939d8921803889d54987314e 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -421,6 +421,7 @@ extern void skb_dma_unmap(struct device *dev, struct sk_buff *skb, #endif extern void kfree_skb(struct sk_buff *skb); +extern void consume_skb(struct sk_buff *skb); extern void __kfree_skb(struct sk_buff *skb); extern struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int fclone, int node); @@ -459,7 +460,8 @@ extern int skb_to_sgvec(struct sk_buff *skb, extern int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer); extern int skb_pad(struct sk_buff *skb, int pad); -#define dev_kfree_skb(a) kfree_skb(a) +#define dev_kfree_skb(a) consume_skb(a) +#define dev_consume_skb(a) kfree_skb_clean(a) extern void skb_over_panic(struct sk_buff *skb, int len, void *here); extern void skb_under_panic(struct sk_buff *skb, int len, diff --git a/net/core/datagram.c b/net/core/datagram.c index 5e2ac0c4b07cfdab7b2a5a2c74e2c2ddcd337328..d0de644b378d5a71e161a905c85d847622df49d2 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -208,7 +208,7 @@ struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, void skb_free_datagram(struct sock *sk, struct sk_buff *skb) { - kfree_skb(skb); + consume_skb(skb); sk_mem_reclaim_partial(sk); } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index e5e2111a397d1d0559ab171c663b5f50c457a2ce..6acbf9e79eb1dc2076bc192f774c8b5591566c42 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -65,6 +65,7 @@ #include #include +#include #include "kmap_skb.h" @@ -442,10 +443,31 @@ void kfree_skb(struct sk_buff *skb) smp_rmb(); else if (likely(!atomic_dec_and_test(&skb->users))) return; + trace_kfree_skb(skb, __builtin_return_address(0)); __kfree_skb(skb); } EXPORT_SYMBOL(kfree_skb); +/** + * consume_skb - free an skbuff + * @skb: buffer to free + * + * Drop a ref to the buffer and free it if the usage count has hit zero + * Functions identically to kfree_skb, but kfree_skb assumes that the frame + * is being dropped after a failure and notes that + */ +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))) + return; + __kfree_skb(skb); +} +EXPORT_SYMBOL(consume_skb); + /** * skb_recycle_check - check if skb can be reused for receive * @skb: buffer diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index 3d67d1ffed7715f2a90aaf50307bab8a9f078b1c..9c220323f3534b0e6dd4397a547cb3040f11ba0b 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -892,7 +892,7 @@ static int arp_process(struct sk_buff *skb) out: if (in_dev) in_dev_put(in_dev); - kfree_skb(skb); + consume_skb(skb); return 0; } diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 4bd178a111d567a81a1219fdcd28ce0e10712b14..05b7abb99f699378674eb107db0f0eedc61bf2e3 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1184,7 +1184,7 @@ static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb, sk = sknext; } while (sknext); } else - kfree_skb(skb); + consume_skb(skb); spin_unlock(&hslot->lock); return 0; } diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index d8cc006fac455cce40956330d561573174b62ca1..74776de523ec52239627bf54ca7c50f546d01627 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -584,7 +584,7 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev, struct packet skb->len = skb_len; } drop: - kfree_skb(skb); + consume_skb(skb); return 0; }