diff options
| -rw-r--r-- | include/net/ip_fib.h | 2 | ||||
| -rw-r--r-- | net/ipv4/route.c | 118 |
2 files changed, 69 insertions, 51 deletions
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index e9ee1ca0708..2daf096dfc6 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -51,7 +51,7 @@ struct fib_nh_exception { struct fib_nh_exception __rcu *fnhe_next; __be32 fnhe_daddr; u32 fnhe_pmtu; - u32 fnhe_gw; + __be32 fnhe_gw; unsigned long fnhe_expires; unsigned long fnhe_stamp; }; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 2c25581bf25..89e39dc5336 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1333,9 +1333,9 @@ static void ip_rt_build_flow_key(struct flowi4 *fl4, const struct sock *sk, build_sk_flow_key(fl4, sk); } -static DEFINE_SPINLOCK(fnhe_lock); +static DEFINE_SEQLOCK(fnhe_seqlock); -static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash, __be32 daddr) +static struct fib_nh_exception *fnhe_oldest(struct fnhe_hash_bucket *hash) { struct fib_nh_exception *fnhe, *oldest; @@ -1358,47 +1358,63 @@ static inline u32 fnhe_hashfun(__be32 daddr) return hval & (FNHE_HASH_SIZE - 1); } -static struct fib_nh_exception *find_or_create_fnhe(struct fib_nh *nh, __be32 daddr) +static void update_or_create_fnhe(struct fib_nh *nh, __be32 daddr, __be32 gw, + u32 pmtu, unsigned long expires) { - struct fnhe_hash_bucket *hash = nh->nh_exceptions; + struct fnhe_hash_bucket *hash; struct fib_nh_exception *fnhe; int depth; - u32 hval; + u32 hval = fnhe_hashfun(daddr); + + write_seqlock_bh(&fnhe_seqlock); + hash = nh->nh_exceptions; if (!hash) { - hash = nh->nh_exceptions = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), - GFP_ATOMIC); + hash = kzalloc(FNHE_HASH_SIZE * sizeof(*hash), GFP_ATOMIC); if (!hash) - return NULL; + goto out_unlock; + nh->nh_exceptions = hash; } - hval = fnhe_hashfun(daddr); hash += hval; depth = 0; for (fnhe = rcu_dereference(hash->chain); fnhe; fnhe = rcu_dereference(fnhe->fnhe_next)) { if (fnhe->fnhe_daddr == daddr) - goto out; + break; depth++; } - if (depth > FNHE_RECLAIM_DEPTH) { - fnhe = fnhe_oldest(hash + hval, daddr); - goto out_daddr; + if (fnhe) { + if (gw) + fnhe->fnhe_gw = gw; + if (pmtu) { + fnhe->fnhe_pmtu = pmtu; + fnhe->fnhe_expires = expires; + } + } else { + if (depth > FNHE_RECLAIM_DEPTH) + fnhe = fnhe_oldest(hash); + else { + fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC); + if (!fnhe) + goto out_unlock; + + fnhe->fnhe_next = hash->chain; + rcu_assign_pointer(hash->chain, fnhe); + } + fnhe->fnhe_daddr = daddr; + fnhe->fnhe_gw = gw; + fnhe->fnhe_pmtu = pmtu; + fnhe->fnhe_expires = expires; } - fnhe = kzalloc(sizeof(*fnhe), GFP_ATOMIC); - if (!fnhe) - return NULL; - - fnhe->fnhe_next = hash->chain; - rcu_assign_pointer(hash->chain, fnhe); -out_daddr: - fnhe->fnhe_daddr = daddr; -out: fnhe->fnhe_stamp = jiffies; - return fnhe; + +out_unlock: + write_sequnlock_bh(&fnhe_seqlock); + return; } static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flowi4 *fl4) @@ -1452,13 +1468,9 @@ static void __ip_do_redirect(struct rtable *rt, struct sk_buff *skb, struct flow } else { if (fib_lookup(net, fl4, &res) == 0) { struct fib_nh *nh = &FIB_RES_NH(res); - struct fib_nh_exception *fnhe; - spin_lock_bh(&fnhe_lock); - fnhe = find_or_create_fnhe(nh, fl4->daddr); - if (fnhe) - fnhe->fnhe_gw = new_gw; - spin_unlock_bh(&fnhe_lock); + update_or_create_fnhe(nh, fl4->daddr, new_gw, + 0, 0); } rt->rt_gateway = new_gw; rt->rt_flags |= RTCF_REDIRECTED; @@ -1663,15 +1675,9 @@ static void __ip_rt_update_pmtu(struct rtable *rt, struct flowi4 *fl4, u32 mtu) if (fib_lookup(dev_net(rt->dst.dev), fl4, &res) == 0) { struct fib_nh *nh = &FIB_RES_NH(res); - struct fib_nh_exception *fnhe; - spin_lock_bh(&fnhe_lock); - fnhe = find_or_create_fnhe(nh, fl4->daddr); - if (fnhe) { - fnhe->fnhe_pmtu = mtu; - fnhe->fnhe_expires = jiffies + ip_rt_mtu_expires; - } - spin_unlock_bh(&fnhe_lock); + update_or_create_fnhe(nh, fl4->daddr, 0, mtu, + jiffies + ip_rt_mtu_expires); } rt->rt_pmtu = mtu; dst_set_expires(&rt->dst, ip_rt_mtu_expires); @@ -1902,23 +1908,35 @@ static void rt_bind_exception(struct rtable *rt, struct fib_nh *nh, __be32 daddr hval = fnhe_hashfun(daddr); +restart: for (fnhe = rcu_dereference(hash[hval].chain); fnhe; fnhe = rcu_dereference(fnhe->fnhe_next)) { - if (fnhe->fnhe_daddr == daddr) { - if (fnhe->fnhe_pmtu) { - unsigned long expires = fnhe->fnhe_expires; - unsigned long diff = expires - jiffies; - - if (time_before(jiffies, expires)) { - rt->rt_pmtu = fnhe->fnhe_pmtu; - dst_set_expires(&rt->dst, diff); - } + __be32 fnhe_daddr, gw; + unsigned long expires; + unsigned int seq; + u32 pmtu; + + seq = read_seqbegin(&fnhe_seqlock); + fnhe_daddr = fnhe->fnhe_daddr; + gw = fnhe->fnhe_gw; + pmtu = fnhe->fnhe_pmtu; + expires = fnhe->fnhe_expires; + if (read_seqretry(&fnhe_seqlock, seq)) + goto restart; + if (daddr != fnhe_daddr) + continue; + if (pmtu) { + unsigned long diff = jiffies - expires; + + if (time_before(jiffies, expires)) { + rt->rt_pmtu = pmtu; + dst_set_expires(&rt->dst, diff); } - if (fnhe->fnhe_gw) - rt->rt_gateway = fnhe->fnhe_gw; - fnhe->fnhe_stamp = jiffies; - break; } + if (gw) + rt->rt_gateway = gw; + fnhe->fnhe_stamp = jiffies; + break; } } |