From 0c5794a66c7c6443759e6098841767958a031187 Mon Sep 17 00:00:00 2001 From: stephen hemminger Date: Mon, 24 Sep 2012 18:12:24 +0000 Subject: [PATCH] gre: remove unnecessary rcu_read_lock/unlock The gre function pointers for receive and error handling are always called (from gre.c) with rcu_read_lock already held. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- net/ipv4/ip_gre.c | 21 +++++++-------------- net/ipv6/ip6_gre.c | 14 +++----------- 2 files changed, 10 insertions(+), 25 deletions(-) diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 0d4c3832d490..1c012cb2cb94 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -557,37 +557,34 @@ static void ipgre_err(struct sk_buff *skb, u32 info) break; } - rcu_read_lock(); t = ipgre_tunnel_lookup(skb->dev, iph->daddr, iph->saddr, flags, key, p[1]); if (t == NULL) - goto out; + return; if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { ipv4_update_pmtu(skb, dev_net(skb->dev), info, t->parms.link, 0, IPPROTO_GRE, 0); - goto out; + return; } if (type == ICMP_REDIRECT) { ipv4_redirect(skb, dev_net(skb->dev), t->parms.link, 0, IPPROTO_GRE, 0); - goto out; + return; } if (t->parms.iph.daddr == 0 || ipv4_is_multicast(t->parms.iph.daddr)) - goto out; + return; if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) - goto out; + return; if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) t->err_count++; else t->err_count = 1; t->err_time = jiffies; -out: - rcu_read_unlock(); } static inline void ipgre_ecn_decapsulate(const struct iphdr *iph, struct sk_buff *skb) @@ -625,7 +622,7 @@ static int ipgre_rcv(struct sk_buff *skb) __be16 gre_proto; if (!pskb_may_pull(skb, 16)) - goto drop_nolock; + goto drop; iph = ip_hdr(skb); h = skb->data; @@ -636,7 +633,7 @@ static int ipgre_rcv(struct sk_buff *skb) - We do not support routing headers. */ if (flags&(GRE_VERSION|GRE_ROUTING)) - goto drop_nolock; + goto drop; if (flags&GRE_CSUM) { switch (skb->ip_summed) { @@ -664,7 +661,6 @@ static int ipgre_rcv(struct sk_buff *skb) gre_proto = *(__be16 *)(h + 2); - rcu_read_lock(); tunnel = ipgre_tunnel_lookup(skb->dev, iph->saddr, iph->daddr, flags, key, gre_proto); @@ -740,14 +736,11 @@ static int ipgre_rcv(struct sk_buff *skb) netif_rx(skb); - rcu_read_unlock(); return 0; } icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); drop: - rcu_read_unlock(); -drop_nolock: kfree_skb(skb); return 0; } diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c index 424d11a4e7ff..b987d4db790f 100644 --- a/net/ipv6/ip6_gre.c +++ b/net/ipv6/ip6_gre.c @@ -437,14 +437,12 @@ static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, ipv6h = (const struct ipv6hdr *)skb->data; p = (__be16 *)(skb->data + offset); - rcu_read_lock(); - t = ip6gre_tunnel_lookup(skb->dev, &ipv6h->daddr, &ipv6h->saddr, flags & GRE_KEY ? *(((__be32 *)p) + (grehlen / 4) - 1) : 0, p[1]); if (t == NULL) - goto out; + return; switch (type) { __u32 teli; @@ -489,8 +487,6 @@ static void ip6gre_err(struct sk_buff *skb, struct inet6_skb_parm *opt, else t->err_count = 1; t->err_time = jiffies; -out: - rcu_read_unlock(); } static inline void ip6gre_ecn_decapsulate_ipv4(const struct ip6_tnl *t, @@ -528,7 +524,7 @@ static int ip6gre_rcv(struct sk_buff *skb) __be16 gre_proto; if (!pskb_may_pull(skb, sizeof(struct in6_addr))) - goto drop_nolock; + goto drop; ipv6h = ipv6_hdr(skb); h = skb->data; @@ -539,7 +535,7 @@ static int ip6gre_rcv(struct sk_buff *skb) - We do not support routing headers. */ if (flags&(GRE_VERSION|GRE_ROUTING)) - goto drop_nolock; + goto drop; if (flags&GRE_CSUM) { switch (skb->ip_summed) { @@ -567,7 +563,6 @@ static int ip6gre_rcv(struct sk_buff *skb) gre_proto = *(__be16 *)(h + 2); - rcu_read_lock(); tunnel = ip6gre_tunnel_lookup(skb->dev, &ipv6h->saddr, &ipv6h->daddr, key, gre_proto); @@ -646,14 +641,11 @@ static int ip6gre_rcv(struct sk_buff *skb) netif_rx(skb); - rcu_read_unlock(); return 0; } icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0); drop: - rcu_read_unlock(); -drop_nolock: kfree_skb(skb); return 0; } -- 2.20.1