path: root/net/core/skbuff.c
diff options
authorJesper Dangaard Brouer <>2016-02-08 13:15:04 +0100
committerDavid S. Miller <>2016-02-11 11:59:09 -0500
commit15fad714be86eab13e7568fecaf475b2a9730d3e (patch)
tree08fa26b84fab14cb2a58b3a01599ffd513d28ba9 /net/core/skbuff.c
parent795bb1c00dd338aa0d12f9a7f1f4776fb3160416 (diff)
net: bulk free SKBs that were delay free'ed due to IRQ context
The network stack defers SKBs free, in-case free happens in IRQ or when IRQs are disabled. This happens in __dev_kfree_skb_irq() that writes SKBs that were free'ed during IRQ to the softirq completion queue (softnet_data.completion_queue). These SKBs are naturally delayed, and cleaned up during NET_TX_SOFTIRQ in function net_tx_action(). Take advantage of this a use the skb defer and flush API, as we are already in softirq context. For modern drivers this rarely happens. Although most drivers do call dev_kfree_skb_any(), which detects the situation and calls __dev_kfree_skb_irq() when needed. This due to netpoll can call from IRQ context. Signed-off-by: Alexander Duyck <> Signed-off-by: Jesper Dangaard Brouer <> Signed-off-by: David S. Miller <>
Diffstat (limited to 'net/core/skbuff.c')
1 files changed, 6 insertions, 2 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index b64187b87773..a5bd067ec1a3 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -767,7 +767,7 @@ void __kfree_skb_flush(void)
-static void __kfree_skb_defer(struct sk_buff *skb)
+static inline void _kfree_skb_defer(struct sk_buff *skb)
struct napi_alloc_cache *nc = this_cpu_ptr(&napi_alloc_cache);
@@ -789,6 +789,10 @@ static void __kfree_skb_defer(struct sk_buff *skb)
nc->skb_count = 0;
+void __kfree_skb_defer(struct sk_buff *skb)
+ _kfree_skb_defer(skb);
void napi_consume_skb(struct sk_buff *skb, int budget)
@@ -814,7 +818,7 @@ void napi_consume_skb(struct sk_buff *skb, int budget)
- __kfree_skb_defer(skb);
+ _kfree_skb_defer(skb);