From 3644f0cee77494190452de132e82245107939284 Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Thu, 7 Dec 2006 15:08:17 -0800 Subject: [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 Signed-off-by: David S. Miller --- include/linux/netdevice.h | 2 +- include/net/neighbour.h | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index c57088f575a..631cec4ff5e 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -199,7 +199,7 @@ struct hh_cache */ u16 hh_len; /* length of header */ int (*hh_output)(struct sk_buff *skb); - rwlock_t hh_lock; + seqlock_t hh_lock; /* cached hardware header; allow for machine alignment needs. */ #define HH_DATA_MOD 16 diff --git a/include/net/neighbour.h b/include/net/neighbour.h index 23967031ddb..3725b93c52f 100644 --- a/include/net/neighbour.h +++ b/include/net/neighbour.h @@ -309,6 +309,24 @@ static inline int neigh_event_send(struct neighbour *neigh, struct sk_buff *skb) return 0; } +static inline int neigh_hh_output(struct hh_cache *hh, struct sk_buff *skb) +{ + unsigned seq; + int hh_len; + + do { + int hh_alen; + + seq = read_seqbegin(&hh->hh_lock); + hh_len = hh->hh_len; + hh_alen = HH_DATA_ALIGN(hh_len); + memcpy(skb->data - hh_alen, hh->hh_data, hh_alen); + } while (read_seqretry(&hh->hh_lock, seq)); + + skb_push(skb, hh_len); + return hh->hh_output(skb); +} + static inline struct neighbour * __neigh_lookup(struct neigh_table *tbl, const void *pkey, struct net_device *dev, int creat) { -- cgit v1.2.3