[NET]: Convert hh_lock to seqlock.

The hard header cache is in the main output path, so using
seqlock instead of reader/writer lock should reduce overhead.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stephen Hemminger
2006-12-07 15:08:17 -08:00
committed by David S. Miller
parent eb991b3938
commit 3644f0cee7
5 changed files with 31 additions and 29 deletions

View File

@@ -164,7 +164,6 @@ EXPORT_SYMBOL_GPL(ip_build_and_send_pkt);
static inline int ip_finish_output2(struct sk_buff *skb)
{
struct dst_entry *dst = skb->dst;
struct hh_cache *hh = dst->hh;
struct net_device *dev = dst->dev;
int hh_len = LL_RESERVED_SPACE(dev);
@@ -183,16 +182,9 @@ static inline int ip_finish_output2(struct sk_buff *skb)
skb = skb2;
}
if (hh) {
int hh_alen;
read_lock_bh(&hh->hh_lock);
hh_alen = HH_DATA_ALIGN(hh->hh_len);
memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
read_unlock_bh(&hh->hh_lock);
skb_push(skb, hh->hh_len);
return hh->hh_output(skb);
} else if (dst->neighbour)
if (dst->hh)
return neigh_hh_output(dst->hh, skb);
else if (dst->neighbour)
return dst->neighbour->output(skb);
if (net_ratelimit())