diff options
| author | Oliver Hartkopp <oliver@hartkopp.net> | 2009-01-06 11:07:54 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-01-06 11:07:54 -0800 |
| commit | 1fa17d4ba43d7e5aab5e90777b07da06524f6748 (patch) | |
| tree | ebe8704bd84c51d29c17a8425b496a13b4935dc5 /net/can/af_can.c | |
| parent | 98658bc9dc37cfb7c3bf5585ca73ce44aeb05c9e (diff) | |
can: omit unneeded skb_clone() calls
The AF_CAN core delivered always cloned sk_buffs to the AF_CAN
protocols, although this was _only_ needed by the can-raw protocol.
With this (additionally documented) change, the AF_CAN core calls the
callback functions of the registered AF_CAN protocols with the original
(uncloned) sk_buff pointer and let's the can-raw protocol do the
skb_clone() itself which omits all unneeded skb_clone() calls for other
AF_CAN protocols.
Signed-off-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/can/af_can.c')
| -rw-r--r-- | net/can/af_can.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/net/can/af_can.c b/net/can/af_can.c index 3dadb338addd..fa417ca6cbe6 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -414,6 +414,12 @@ static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask, * The filter can be inverted (CAN_INV_FILTER bit set in can_id) or it can * filter for error frames (CAN_ERR_FLAG bit set in mask). * + * The provided pointer to the sk_buff is guaranteed to be valid as long as + * the callback function is running. The callback function must *not* free + * the given sk_buff while processing it's task. When the given sk_buff is + * needed after the end of the callback function it must be cloned inside + * the callback function with skb_clone(). + * * Return: * 0 on success * -ENOMEM on missing cache mem to create subscription entry @@ -569,13 +575,8 @@ EXPORT_SYMBOL(can_rx_unregister); static inline void deliver(struct sk_buff *skb, struct receiver *r) { - struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC); - - if (clone) { - clone->sk = skb->sk; - r->func(clone, r->data); - r->matches++; - } + r->func(skb, r->data); + r->matches++; } static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb) |