From 66018506e15bea62de4eefc3298f170b4bfcf5ef Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 7 Jun 2010 03:12:08 +0000 Subject: ip: Router Alert RCU conversion Straightforward conversion to RCU. One rwlock becomes a spinlock, and is static. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/ip_input.c | 11 +++-------- net/ipv4/ip_sockglue.c | 23 ++++++++++++++--------- 2 files changed, 17 insertions(+), 17 deletions(-) (limited to 'net') diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index d52c9da644c..d274078b166 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -146,7 +146,7 @@ #include /* - * Process Router Attention IP option + * Process Router Attention IP option (RFC 2113) */ int ip_call_ra_chain(struct sk_buff *skb) { @@ -155,8 +155,7 @@ int ip_call_ra_chain(struct sk_buff *skb) struct sock *last = NULL; struct net_device *dev = skb->dev; - read_lock(&ip_ra_lock); - for (ra = ip_ra_chain; ra; ra = ra->next) { + for (ra = rcu_dereference(ip_ra_chain); ra; ra = rcu_dereference(ra->next)) { struct sock *sk = ra->sk; /* If socket is bound to an interface, only report @@ -167,10 +166,8 @@ int ip_call_ra_chain(struct sk_buff *skb) sk->sk_bound_dev_if == dev->ifindex) && net_eq(sock_net(sk), dev_net(dev))) { if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) { - if (ip_defrag(skb, IP_DEFRAG_CALL_RA_CHAIN)) { - read_unlock(&ip_ra_lock); + if (ip_defrag(skb, IP_DEFRAG_CALL_RA_CHAIN)) return 1; - } } if (last) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); @@ -183,10 +180,8 @@ int ip_call_ra_chain(struct sk_buff *skb) if (last) { raw_rcv(last, skb); - read_unlock(&ip_ra_lock); return 1; } - read_unlock(&ip_ra_lock); return 0; } diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index ce231780a2b..08b9519a24f 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -239,7 +239,12 @@ int ip_cmsg_send(struct net *net, struct msghdr *msg, struct ipcm_cookie *ipc) sent to multicast group to reach destination designated router. */ struct ip_ra_chain *ip_ra_chain; -DEFINE_RWLOCK(ip_ra_lock); +static DEFINE_SPINLOCK(ip_ra_lock); + +static void ip_ra_free_rcu(struct rcu_head *head) +{ + kfree(container_of(head, struct ip_ra_chain, rcu)); +} int ip_ra_control(struct sock *sk, unsigned char on, void (*destructor)(struct sock *)) @@ -251,35 +256,35 @@ int ip_ra_control(struct sock *sk, unsigned char on, new_ra = on ? kmalloc(sizeof(*new_ra), GFP_KERNEL) : NULL; - write_lock_bh(&ip_ra_lock); + spin_lock_bh(&ip_ra_lock); for (rap = &ip_ra_chain; (ra = *rap) != NULL; rap = &ra->next) { if (ra->sk == sk) { if (on) { - write_unlock_bh(&ip_ra_lock); + spin_unlock_bh(&ip_ra_lock); kfree(new_ra); return -EADDRINUSE; } - *rap = ra->next; - write_unlock_bh(&ip_ra_lock); + rcu_assign_pointer(*rap, ra->next); + spin_unlock_bh(&ip_ra_lock); if (ra->destructor) ra->destructor(sk); sock_put(sk); - kfree(ra); + call_rcu(&ra->rcu, ip_ra_free_rcu); return 0; } } if (new_ra == NULL) { - write_unlock_bh(&ip_ra_lock); + spin_unlock_bh(&ip_ra_lock); return -ENOBUFS; } new_ra->sk = sk; new_ra->destructor = destructor; new_ra->next = ra; - *rap = new_ra; + rcu_assign_pointer(*rap, new_ra); sock_hold(sk); - write_unlock_bh(&ip_ra_lock); + spin_unlock_bh(&ip_ra_lock); return 0; } -- cgit v1.2.3-70-g09d2