ipv4: Add hash table of interface addresses.
This will be used to optimize __ip_dev_find() and friends.
With help from Eric Dumazet.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 748cb5b..2fe5076 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -51,6 +51,7 @@
#include <linux/inetdevice.h>
#include <linux/igmp.h>
#include <linux/slab.h>
+#include <linux/hash.h>
#ifdef CONFIG_SYSCTL
#include <linux/sysctl.h>
#endif
@@ -92,6 +93,38 @@
[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
+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)
+{
+ u32 val = (__force u32) addr ^ hash_ptr(net, 8);
+
+ return ((val ^ (val >> 8) ^ (val >> 16) ^ (val >> 24)) &
+ (IN4_ADDR_HSIZE - 1));
+}
+
+static void inet_hash_insert(struct net *net, struct in_ifaddr *ifa)
+{
+ unsigned int hash = inet_addr_hash(net, ifa->ifa_address);
+
+ spin_lock(&inet_addr_hash_lock);
+ hlist_add_head_rcu(&ifa->hash, &inet_addr_lst[hash]);
+ spin_unlock(&inet_addr_hash_lock);
+}
+
+static void inet_hash_remove(struct in_ifaddr *ifa)
+{
+ spin_lock(&inet_addr_hash_lock);
+ hlist_del_init_rcu(&ifa->hash);
+ spin_unlock(&inet_addr_hash_lock);
+}
+
static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
@@ -265,6 +298,7 @@
}
if (!do_promote) {
+ inet_hash_remove(ifa);
*ifap1 = ifa->ifa_next;
rtmsg_ifa(RTM_DELADDR, ifa, nlh, pid);
@@ -281,6 +315,7 @@
/* 2. Unlink it */
*ifap = ifa1->ifa_next;
+ inet_hash_remove(ifa1);
/* 3. Announce address deletion */
@@ -368,6 +403,8 @@
ifa->ifa_next = *ifap;
*ifap = ifa;
+ inet_hash_insert(dev_net(in_dev->dev), ifa);
+
/* Send message first, then call notifier.
Notifier will trigger FIB update, so that
listeners of netlink will know about new ifaddr */
@@ -521,6 +558,7 @@
if (tb[IFA_ADDRESS] == NULL)
tb[IFA_ADDRESS] = tb[IFA_LOCAL];
+ INIT_HLIST_NODE(&ifa->hash);
ifa->ifa_prefixlen = ifm->ifa_prefixlen;
ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
ifa->ifa_flags = ifm->ifa_flags;
@@ -728,6 +766,7 @@
if (!ifa) {
ret = -ENOBUFS;
ifa = inet_alloc_ifa();
+ INIT_HLIST_NODE(&ifa->hash);
if (!ifa)
break;
if (colon)
@@ -1069,6 +1108,7 @@
struct in_ifaddr *ifa = inet_alloc_ifa();
if (ifa) {
+ INIT_HLIST_NODE(&ifa->hash);
ifa->ifa_local =
ifa->ifa_address = htonl(INADDR_LOOPBACK);
ifa->ifa_prefixlen = 8;
@@ -1710,6 +1750,11 @@
void __init devinet_init(void)
{
+ int i;
+
+ for (i = 0; i < IN4_ADDR_HSIZE; i++)
+ INIT_HLIST_HEAD(&inet_addr_lst[i]);
+
register_pernet_subsys(&devinet_ops);
register_gifconf(PF_INET, inet_gifconf);