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IPv6: convert addrconf hash list to RCU 

Convert from reader/writer lock to RCU and spinlock for addrconf
hash list.

Adds an additional helper macro for hlist_for_each_entry_continue_rcu
to handle the continue case.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
hifive-unleashed-5.1
stephen hemminger 2010-03-17 20:31:11 +00:00 committed by David S. Miller
parent c2e21293c0
commit 5c578aedcb
3 changed files with 58 additions and 41 deletions
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13
include/linux/rculist.h
View File

@ -428,5 +428,18 @@ static inline void hlist_add_after_rcu(struct hlist_node *prev,
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); \ ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); \
pos = rcu_dereference_raw(pos->next)) pos = rcu_dereference_raw(pos->next))
/**
* hlist_for_each_entry_continue_rcu - iterate over a hlist continuing after current point
* @tpos: the type * to use as a loop cursor.
* @pos: the &struct hlist_node to use as a loop cursor.
* @member: the name of the hlist_node within the struct.
*/
#define hlist_for_each_entry_continue_rcu(tpos, pos, member) \
for (pos = rcu_dereference((pos)->next); \
pos && ({ prefetch(pos->next); 1; }) && \
({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); \
pos = rcu_dereference(pos->next))
#endif /* __KERNEL__ */ #endif /* __KERNEL__ */
#endif #endif

1
include/net/if_inet6.h
View File

@ -64,6 +64,7 @@ struct inet6_ifaddr {
#endif #endif
int dead; int dead;
struct rcu_head rcu;
}; };
struct ip6_sf_socklist { struct ip6_sf_socklist {

85
net/ipv6/addrconf.c
View File

@ -127,7 +127,7 @@ static int ipv6_count_addresses(struct inet6_dev *idev);
* Configured unicast address hash table * Configured unicast address hash table
*/ */
static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE]; static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
static DEFINE_RWLOCK(addrconf_hash_lock); static DEFINE_SPINLOCK(addrconf_hash_lock);
static void addrconf_verify(unsigned long); static void addrconf_verify(unsigned long);
@ -523,8 +523,13 @@ static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int old)
} }
#endif #endif
/* Nobody refers to this ifaddr, destroy it */ static void inet6_ifa_finish_destroy_rcu(struct rcu_head *head)
{
struct inet6_ifaddr *ifp = container_of(head, struct inet6_ifaddr, rcu);
kfree(ifp);
}
/* Nobody refers to this ifaddr, destroy it */
void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp) void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
{ {
WARN_ON(ifp->if_next != NULL); WARN_ON(ifp->if_next != NULL);
@ -545,7 +550,7 @@ void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
} }
dst_release(&ifp->rt->u.dst); dst_release(&ifp->rt->u.dst);
kfree(ifp); call_rcu(&ifp->rcu, inet6_ifa_finish_destroy_rcu);
} }
static void static void
@ -616,7 +621,7 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
goto out2; goto out2;
} }
write_lock(&addrconf_hash_lock); spin_lock(&addrconf_hash_lock);
/* Ignore adding duplicate addresses on an interface */ /* Ignore adding duplicate addresses on an interface */
if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) { if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
@ -670,9 +675,9 @@ ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
/* Add to big hash table */ /* Add to big hash table */
hash = ipv6_addr_hash(addr); hash = ipv6_addr_hash(addr);
hlist_add_head(&ifa->addr_lst, &inet6_addr_lst[hash]); hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
in6_ifa_hold(ifa); in6_ifa_hold(ifa);
write_unlock(&addrconf_hash_lock); spin_unlock(&addrconf_hash_lock);
write_lock(&idev->lock); write_lock(&idev->lock);
/* Add to inet6_dev unicast addr list. */ /* Add to inet6_dev unicast addr list. */
@ -699,7 +704,7 @@ out2:
return ifa; return ifa;
out: out:
write_unlock(&addrconf_hash_lock); spin_unlock(&addrconf_hash_lock);
goto out2; goto out2;
} }
@ -717,10 +722,10 @@ static void ipv6_del_addr(struct inet6_ifaddr *ifp)
ifp->dead = 1; ifp->dead = 1;
write_lock_bh(&addrconf_hash_lock); spin_lock_bh(&addrconf_hash_lock);
hlist_del_init(&ifp->addr_lst); hlist_del_init_rcu(&ifp->addr_lst);
__in6_ifa_put(ifp); __in6_ifa_put(ifp);
write_unlock_bh(&addrconf_hash_lock); spin_unlock_bh(&addrconf_hash_lock);
write_lock_bh(&idev->lock); write_lock_bh(&idev->lock);
#ifdef CONFIG_IPV6_PRIVACY #ifdef CONFIG_IPV6_PRIVACY
@ -1274,8 +1279,8 @@ int ipv6_chk_addr(struct net *net, struct in6_addr *addr,
struct hlist_node *node; struct hlist_node *node;
u8 hash = ipv6_addr_hash(addr); u8 hash = ipv6_addr_hash(addr);
read_lock_bh(&addrconf_hash_lock); rcu_read_lock_bh();
hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) { hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
if (!net_eq(dev_net(ifp->idev->dev), net)) if (!net_eq(dev_net(ifp->idev->dev), net))
continue; continue;
if (ipv6_addr_equal(&ifp->addr, addr) && if (ipv6_addr_equal(&ifp->addr, addr) &&
@ -1285,7 +1290,8 @@ int ipv6_chk_addr(struct net *net, struct in6_addr *addr,
break; break;
} }
} }
read_unlock_bh(&addrconf_hash_lock); rcu_read_unlock_bh();
return ifp != NULL; return ifp != NULL;
} }
EXPORT_SYMBOL(ipv6_chk_addr); EXPORT_SYMBOL(ipv6_chk_addr);
@ -1341,8 +1347,8 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add
struct hlist_node *node; struct hlist_node *node;
u8 hash = ipv6_addr_hash(addr); u8 hash = ipv6_addr_hash(addr);
read_lock_bh(&addrconf_hash_lock); rcu_read_lock_bh();
hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) { hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
if (!net_eq(dev_net(ifp->idev->dev), net)) if (!net_eq(dev_net(ifp->idev->dev), net))
continue; continue;
if (ipv6_addr_equal(&ifp->addr, addr)) { if (ipv6_addr_equal(&ifp->addr, addr)) {
@ -1353,7 +1359,7 @@ struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *add
} }
} }
} }
read_unlock_bh(&addrconf_hash_lock); rcu_read_unlock_bh();
return ifp; return ifp;
} }
@ -2698,10 +2704,10 @@ static int addrconf_ifdown(struct net_device *dev, int how)
write_unlock_bh(&idev->lock); write_unlock_bh(&idev->lock);
/* clear hash table */ /* clear hash table */
write_lock_bh(&addrconf_hash_lock); spin_lock_bh(&addrconf_hash_lock);
hlist_del_init(&ifa->addr_lst); hlist_del_init_rcu(&ifa->addr_lst);
__in6_ifa_put(ifa); __in6_ifa_put(ifa);
write_unlock_bh(&addrconf_hash_lock); spin_unlock_bh(&addrconf_hash_lock);
__ipv6_ifa_notify(RTM_DELADDR, ifa); __ipv6_ifa_notify(RTM_DELADDR, ifa);
atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa); atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
@ -2946,11 +2952,10 @@ static struct inet6_ifaddr *if6_get_first(struct seq_file *seq)
for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) { for (state->bucket = 0; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
struct hlist_node *n; struct hlist_node *n;
hlist_for_each_entry(ifa, n, hlist_for_each_entry_rcu(ifa, n, &inet6_addr_lst[state->bucket],
&inet6_addr_lst[state->bucket], addr_lst) { addr_lst)
if (net_eq(dev_net(ifa->idev->dev), net)) if (net_eq(dev_net(ifa->idev->dev), net))
return ifa; return ifa;
}
} }
return NULL; return NULL;
} }
@ -2962,10 +2967,9 @@ static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
struct net *net = seq_file_net(seq); struct net *net = seq_file_net(seq);
struct hlist_node *n = &ifa->addr_lst; struct hlist_node *n = &ifa->addr_lst;
hlist_for_each_entry_continue(ifa, n, addr_lst) { hlist_for_each_entry_continue_rcu(ifa, n, addr_lst)
if (net_eq(dev_net(ifa->idev->dev), net)) if (net_eq(dev_net(ifa->idev->dev), net))
return ifa; return ifa;
}
while (++state->bucket < IN6_ADDR_HSIZE) { while (++state->bucket < IN6_ADDR_HSIZE) {
hlist_for_each_entry(ifa, n, hlist_for_each_entry(ifa, n,
@ -2989,9 +2993,9 @@ static struct inet6_ifaddr *if6_get_idx(struct seq_file *seq, loff_t pos)
} }
static void *if6_seq_start(struct seq_file *seq, loff_t *pos) static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
__acquires(addrconf_hash_lock) __acquires(rcu)
{ {
read_lock_bh(&addrconf_hash_lock); rcu_read_lock_bh();
return if6_get_idx(seq, *pos); return if6_get_idx(seq, *pos);
} }
@ -3005,9 +3009,9 @@ static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
} }
static void if6_seq_stop(struct seq_file *seq, void *v) static void if6_seq_stop(struct seq_file *seq, void *v)
__releases(addrconf_hash_lock) __releases(rcu)
{ {
read_unlock_bh(&addrconf_hash_lock); rcu_read_unlock_bh();
} }
static int if6_seq_show(struct seq_file *seq, void *v) static int if6_seq_show(struct seq_file *seq, void *v)
@ -3081,8 +3085,8 @@ int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr)
struct hlist_node *n; struct hlist_node *n;
u8 hash = ipv6_addr_hash(addr); u8 hash = ipv6_addr_hash(addr);
read_lock_bh(&addrconf_hash_lock); rcu_read_lock_bh();
hlist_for_each_entry(ifp, n, &inet6_addr_lst[hash], addr_lst) { hlist_for_each_entry_rcu(ifp, n, &inet6_addr_lst[hash], addr_lst) {
if (!net_eq(dev_net(ifp->idev->dev), net)) if (!net_eq(dev_net(ifp->idev->dev), net))
continue; continue;
if (ipv6_addr_equal(&ifp->addr, addr) && if (ipv6_addr_equal(&ifp->addr, addr) &&
@ -3091,7 +3095,7 @@ int ipv6_chk_home_addr(struct net *net, struct in6_addr *addr)
break; break;
} }
} }
read_unlock_bh(&addrconf_hash_lock); rcu_read_unlock_bh();
return ret; return ret;
} }
#endif #endif
@ -3107,7 +3111,8 @@ static void addrconf_verify(unsigned long foo)
unsigned long now, next; unsigned long now, next;
int i; int i;
spin_lock_bh(&addrconf_verify_lock); rcu_read_lock_bh();
spin_lock(&addrconf_verify_lock);
now = jiffies; now = jiffies;
next = now + ADDR_CHECK_FREQUENCY; next = now + ADDR_CHECK_FREQUENCY;
@ -3116,8 +3121,8 @@ static void addrconf_verify(unsigned long foo)
for (i=0; i < IN6_ADDR_HSIZE; i++) { for (i=0; i < IN6_ADDR_HSIZE; i++) {
restart: restart:
read_lock(&addrconf_hash_lock); hlist_for_each_entry_rcu(ifp, node,
hlist_for_each_entry(ifp, node, &inet6_addr_lst[i], addr_lst) { &inet6_addr_lst[i], addr_lst) {
unsigned long age; unsigned long age;
#ifdef CONFIG_IPV6_PRIVACY #ifdef CONFIG_IPV6_PRIVACY
unsigned long regen_advance; unsigned long regen_advance;
@ -3139,7 +3144,6 @@ restart:
age >= ifp->valid_lft) { age >= ifp->valid_lft) {
spin_unlock(&ifp->lock); spin_unlock(&ifp->lock);
in6_ifa_hold(ifp); in6_ifa_hold(ifp);
read_unlock(&addrconf_hash_lock);
ipv6_del_addr(ifp); ipv6_del_addr(ifp);
goto restart; goto restart;
} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) { } else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
@ -3161,7 +3165,6 @@ restart:
if (deprecate) { if (deprecate) {
in6_ifa_hold(ifp); in6_ifa_hold(ifp);
read_unlock(&addrconf_hash_lock);
ipv6_ifa_notify(0, ifp); ipv6_ifa_notify(0, ifp);
in6_ifa_put(ifp); in6_ifa_put(ifp);
@ -3179,7 +3182,7 @@ restart:
in6_ifa_hold(ifp); in6_ifa_hold(ifp);
in6_ifa_hold(ifpub); in6_ifa_hold(ifpub);
spin_unlock(&ifp->lock); spin_unlock(&ifp->lock);
read_unlock(&addrconf_hash_lock);
spin_lock(&ifpub->lock); spin_lock(&ifpub->lock);
ifpub->regen_count = 0; ifpub->regen_count = 0;
spin_unlock(&ifpub->lock); spin_unlock(&ifpub->lock);
@ -3199,12 +3202,12 @@ restart:
spin_unlock(&ifp->lock); spin_unlock(&ifp->lock);
} }
} }
read_unlock(&addrconf_hash_lock);
} }
addr_chk_timer.expires = time_before(next, jiffies + HZ) ? jiffies + HZ : next; addr_chk_timer.expires = time_before(next, jiffies + HZ) ? jiffies + HZ : next;
add_timer(&addr_chk_timer); add_timer(&addr_chk_timer);
spin_unlock_bh(&addrconf_verify_lock); spin_unlock(&addrconf_verify_lock);
rcu_read_unlock_bh();
} }
static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local) static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
@ -4621,10 +4624,10 @@ void addrconf_cleanup(void)
/* /*
* Check hash table. * Check hash table.
*/ */
write_lock_bh(&addrconf_hash_lock); spin_lock_bh(&addrconf_hash_lock);
for (i = 0; i < IN6_ADDR_HSIZE; i++) for (i = 0; i < IN6_ADDR_HSIZE; i++)
WARN_ON(!hlist_empty(&inet6_addr_lst[i])); WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
write_unlock_bh(&addrconf_hash_lock); spin_unlock_bh(&addrconf_hash_lock);
del_timer(&addr_chk_timer); del_timer(&addr_chk_timer);
rtnl_unlock(); rtnl_unlock();