From 40384999d142552b81aeb596c2ae663dd3ff60ce Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 3 Aug 2012 21:06:50 +0000 Subject: [PATCH] ipv4: change inet_addr_hash() Use net_hash_mix(net) instead of hash_ptr(net, 8), and use hash_32() instead of using a serie of XOR Define IN4_ADDR_HSIZE_SHIFT for clarity __ip_dev_find() can perform the net_eq() call only if ifa_local matches the key, to avoid unneeded dereferences. remove inline attributes # size net/ipv4/devinet.o.before net/ipv4/devinet.o text data bss dec hex filename 17471 2545 2048 22064 5630 net/ipv4/devinet.o.before 17335 2545 2048 21928 55a8 net/ipv4/devinet.o Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv4/devinet.c | 39 ++++++++++++++++++--------------------- 1 file changed, 18 insertions(+), 21 deletions(-) diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 44bf82e3aef7..adf273f8ad2e 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -94,25 +94,22 @@ static const struct nla_policy ifa_ipv4_policy[IFA_MAX+1] = { [IFA_LABEL] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, }; -/* inet_addr_hash's shifting is dependent upon this IN4_ADDR_HSIZE - * value. So if you change this define, make appropriate changes to - * inet_addr_hash as well. - */ -#define IN4_ADDR_HSIZE 256 +#define IN4_ADDR_HSIZE_SHIFT 8 +#define IN4_ADDR_HSIZE (1U << IN4_ADDR_HSIZE_SHIFT) + static struct hlist_head inet_addr_lst[IN4_ADDR_HSIZE]; static DEFINE_SPINLOCK(inet_addr_hash_lock); -static inline unsigned int inet_addr_hash(struct net *net, __be32 addr) +static u32 inet_addr_hash(struct net *net, __be32 addr) { - u32 val = (__force u32) addr ^ hash_ptr(net, 8); + u32 val = (__force u32) addr ^ net_hash_mix(net); - return ((val ^ (val >> 8) ^ (val >> 16) ^ (val >> 24)) & - (IN4_ADDR_HSIZE - 1)); + return hash_32(val, IN4_ADDR_HSIZE_SHIFT); } static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa) { - unsigned int hash = inet_addr_hash(net, ifa->ifa_local); + u32 hash = inet_addr_hash(net, ifa->ifa_local); spin_lock(&inet_addr_hash_lock); hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]); @@ -136,18 +133,18 @@ static void inet_hash_remove(struct in_ifaddr *ifa) */ struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref) { - unsigned int hash = inet_addr_hash(net, addr); + u32 hash = inet_addr_hash(net, addr); struct net_device *result = NULL; struct in_ifaddr *ifa; struct hlist_node *node; rcu_read_lock(); hlist_for_each_entry_rcu(ifa, node, &inet_addr_lst[hash], hash) { - struct net_device *dev = ifa->ifa_dev->dev; - - if (!net_eq(dev_net(dev), net)) - continue; if (ifa->ifa_local == addr) { + struct net_device *dev = ifa->ifa_dev->dev; + + if (!net_eq(dev_net(dev), net)) + continue; result = dev; break; } @@ -182,10 +179,10 @@ static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, static void devinet_sysctl_register(struct in_device *idev); static void devinet_sysctl_unregister(struct in_device *idev); #else -static inline void devinet_sysctl_register(struct in_device *idev) +static void devinet_sysctl_register(struct in_device *idev) { } -static inline void devinet_sysctl_unregister(struct in_device *idev) +static void devinet_sysctl_unregister(struct in_device *idev) { } #endif @@ -205,7 +202,7 @@ static void inet_rcu_free_ifa(struct rcu_head *head) kfree(ifa); } -static inline void inet_free_ifa(struct in_ifaddr *ifa) +static void inet_free_ifa(struct in_ifaddr *ifa) { call_rcu(&ifa->rcu_head, inet_rcu_free_ifa); } @@ -659,7 +656,7 @@ static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg * Determine a default network mask, based on the IP address. */ -static inline int inet_abc_len(__be32 addr) +static int inet_abc_len(__be32 addr) { int rc = -1; /* Something else, probably a multicast. */ @@ -1124,7 +1121,7 @@ skip: } } -static inline bool inetdev_valid_mtu(unsigned int mtu) +static bool inetdev_valid_mtu(unsigned int mtu) { return mtu >= 68; } @@ -1239,7 +1236,7 @@ static struct notifier_block ip_netdev_notifier = { .notifier_call = inetdev_event, }; -static inline size_t inet_nlmsg_size(void) +static size_t inet_nlmsg_size(void) { return NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + nla_total_size(4) /* IFA_ADDRESS */ -- 2.20.1