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ipv4: Namespacify IPv4 address GC.

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Each IPv4 address could have a lifetime, which is useful for DHCP,
and GC is periodically executed as check_lifetime_work.

check_lifetime() does the actual GC under RTNL.

  1. Acquire RTNL
  2. Iterate inet_addr_lst
  3. Remove IPv4 address if expired
  4. Release RTNL

Namespacifying the GC is required for per-netns RTNL, but using the
per-netns hash table will shorten the time on the hash bucket iteration
under RTNL.

Let's add per-netns GC work and use the per-netns hash table.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241008172906.1326-4-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This commit is contained in:
Kuniyuki Iwashima 2024-10-08 10:29:05 -07:00 committed by Jakub Kicinski
parent 49e6131942
commit 1675f38521
2 changed files with 19 additions and 14 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

1
include/net/netns/ipv4.h
View file

@ -271,5 +271,6 @@ struct netns_ipv4 {
atomic_t rt_genid;
siphash_key_t ip_id_key;
struct hlist_head *inet_addr_lst;
struct delayed_work addr_chk_work;
};
#endif

30
net/ipv4/devinet.c
View file

@ -486,15 +486,12 @@ static void inet_del_ifa(struct in_device *in_dev,
__inet_del_ifa(in_dev, ifap, destroy, NULL, 0);
}
static void check_lifetime(struct work_struct *work);
static DECLARE_DELAYED_WORK(check_lifetime_work, check_lifetime);
static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
u32 portid, struct netlink_ext_ack *extack)
{
struct in_ifaddr __rcu **last_primary, **ifap;
struct in_device *in_dev = ifa->ifa_dev;
struct net *net = dev_net(in_dev->dev);
struct in_validator_info ivi;
struct in_ifaddr *ifa1;
int ret;
@ -563,8 +560,8 @@ static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
inet_hash_insert(dev_net(in_dev->dev), ifa);
cancel_delayed_work(&check_lifetime_work);
queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
cancel_delayed_work(&net->ipv4.addr_chk_work);
queue_delayed_work(system_power_efficient_wq, &net->ipv4.addr_chk_work, 0);
/* Send message first, then call notifier.
Notifier will trigger FIB update, so that
@ -710,16 +707,19 @@ static void check_lifetime(struct work_struct *work)
unsigned long now, next, next_sec, next_sched;
struct in_ifaddr *ifa;
struct hlist_node *n;
struct net *net;
int i;
net = container_of(to_delayed_work(work), struct net, ipv4.addr_chk_work);
now = jiffies;
next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
for (i = 0; i < IN4_ADDR_HSIZE; i++) {
struct hlist_head *head = &net->ipv4.inet_addr_lst[i];
bool change_needed = false;
rcu_read_lock();
hlist_for_each_entry_rcu(ifa, &inet_addr_lst[i], hash) {
hlist_for_each_entry_rcu(ifa, head, addr_lst) {
unsigned long age, tstamp;
u32 preferred_lft;
u32 valid_lft;
@ -757,7 +757,7 @@ static void check_lifetime(struct work_struct *work)
if (!change_needed)
continue;
rtnl_lock();
hlist_for_each_entry_safe(ifa, n, &inet_addr_lst[i], hash) {
hlist_for_each_entry_safe(ifa, n, head, addr_lst) {
unsigned long age;
if (ifa->ifa_flags & IFA_F_PERMANENT)
@ -806,7 +806,7 @@ static void check_lifetime(struct work_struct *work)
if (time_before(next_sched, now + ADDRCONF_TIMER_FUZZ_MAX))
next_sched = now + ADDRCONF_TIMER_FUZZ_MAX;
queue_delayed_work(system_power_efficient_wq, &check_lifetime_work,
queue_delayed_work(system_power_efficient_wq, &net->ipv4.addr_chk_work,
next_sched - now);
}
@ -1004,9 +1004,9 @@ static int inet_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
ifa->ifa_proto = new_proto;
set_ifa_lifetime(ifa, valid_lft, prefered_lft);
cancel_delayed_work(&check_lifetime_work);
cancel_delayed_work(&net->ipv4.addr_chk_work);
queue_delayed_work(system_power_efficient_wq,
&check_lifetime_work, 0);
&net->ipv4.addr_chk_work, 0);
rtmsg_ifa(RTM_NEWADDR, ifa, nlh, NETLINK_CB(skb).portid);
}
return 0;
@ -2743,6 +2743,8 @@ static __net_init int devinet_init_net(struct net *net)
for (i = 0; i < IN4_ADDR_HSIZE; i++)
INIT_HLIST_HEAD(&net->ipv4.inet_addr_lst[i]);
INIT_DEFERRABLE_WORK(&net->ipv4.addr_chk_work, check_lifetime);
net->ipv4.devconf_all = all;
net->ipv4.devconf_dflt = dflt;
return 0;
@ -2769,7 +2771,11 @@ static __net_exit void devinet_exit_net(struct net *net)
{
#ifdef CONFIG_SYSCTL
const struct ctl_table *tbl;
#endif
cancel_delayed_work_sync(&net->ipv4.addr_chk_work);
#ifdef CONFIG_SYSCTL
tbl = net->ipv4.forw_hdr->ctl_table_arg;
unregister_net_sysctl_table(net->ipv4.forw_hdr);
__devinet_sysctl_unregister(net, net->ipv4.devconf_dflt,
@ -2806,8 +2812,6 @@ void __init devinet_init(void)
register_pernet_subsys(&devinet_ops);
register_netdevice_notifier(&ip_netdev_notifier);
queue_delayed_work(system_power_efficient_wq, &check_lifetime_work, 0);
rtnl_af_register(&inet_af_ops);
rtnl_register(PF_INET, RTM_NEWADDR, inet_rtm_newaddr, NULL, 0);