net: Add support for batching network namespace cleanups

- Add exit_list to struct net to support building lists of network
  namespaces to cleanup.

- Add exit_batch to pernet_operations to allow running operations only
  once during a network namespace exit.  Instead of once per network
  namespace.

- Factor opt ops_exit_list and ops_exit_free so the logic with cleanup
  up a network namespace does not need to be duplicated.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric W. Biederman 2009-12-03 02:29:03 +00:00 committed by David S. Miller
parent 8153a10c08
commit 72ad937abd
2 changed files with 63 additions and 61 deletions

View File

@ -43,6 +43,7 @@ struct net {
#endif
struct list_head list; /* list of network namespaces */
struct list_head cleanup_list; /* namespaces on death row */
struct list_head exit_list; /* Use only net_mutex */
struct proc_dir_entry *proc_net;
struct proc_dir_entry *proc_net_stat;
@ -236,6 +237,7 @@ struct pernet_operations {
struct list_head list;
int (*init)(struct net *net);
void (*exit)(struct net *net);
void (*exit_batch)(struct list_head *net_exit_list);
int *id;
size_t size;
};

View File

@ -70,6 +70,36 @@ static void ops_free(const struct pernet_operations *ops, struct net *net)
}
}
static void ops_exit_list(const struct pernet_operations *ops,
struct list_head *net_exit_list)
{
struct net *net;
if (ops->exit) {
list_for_each_entry(net, net_exit_list, exit_list)
ops->exit(net);
}
if (&ops->list == first_device) {
LIST_HEAD(dev_kill_list);
rtnl_lock();
list_for_each_entry(net, net_exit_list, exit_list)
unregister_netdevices(net, &dev_kill_list);
unregister_netdevice_many(&dev_kill_list);
rtnl_unlock();
}
if (ops->exit_batch)
ops->exit_batch(net_exit_list);
}
static void ops_free_list(const struct pernet_operations *ops,
struct list_head *net_exit_list)
{
struct net *net;
if (ops->size && ops->id) {
list_for_each_entry(net, net_exit_list, exit_list)
ops_free(ops, net);
}
}
/*
* setup_net runs the initializers for the network namespace object.
*/
@ -78,6 +108,7 @@ static __net_init int setup_net(struct net *net)
/* Must be called with net_mutex held */
const struct pernet_operations *ops, *saved_ops;
int error = 0;
LIST_HEAD(net_exit_list);
atomic_set(&net->count, 1);
@ -97,21 +128,14 @@ static __net_init int setup_net(struct net *net)
/* Walk through the list backwards calling the exit functions
* for the pernet modules whose init functions did not fail.
*/
list_add(&net->exit_list, &net_exit_list);
saved_ops = ops;
list_for_each_entry_continue_reverse(ops, &pernet_list, list) {
if (ops->exit)
ops->exit(net);
if (&ops->list == first_device) {
LIST_HEAD(dev_kill_list);
rtnl_lock();
unregister_netdevices(net, &dev_kill_list);
unregister_netdevice_many(&dev_kill_list);
rtnl_unlock();
}
}
list_for_each_entry_continue_reverse(ops, &pernet_list, list)
ops_exit_list(ops, &net_exit_list);
ops = saved_ops;
list_for_each_entry_continue_reverse(ops, &pernet_list, list)
ops_free(ops, net);
ops_free_list(ops, &net_exit_list);
rcu_barrier();
goto out;
@ -207,6 +231,7 @@ static void cleanup_net(struct work_struct *work)
const struct pernet_operations *ops;
struct net *net, *tmp;
LIST_HEAD(net_kill_list);
LIST_HEAD(net_exit_list);
/* Atomically snapshot the list of namespaces to cleanup */
spin_lock_irq(&cleanup_list_lock);
@ -217,8 +242,10 @@ static void cleanup_net(struct work_struct *work)
/* Don't let anyone else find us. */
rtnl_lock();
list_for_each_entry(net, &net_kill_list, cleanup_list)
list_for_each_entry(net, &net_kill_list, cleanup_list) {
list_del_rcu(&net->list);
list_add_tail(&net->exit_list, &net_exit_list);
}
rtnl_unlock();
/*
@ -229,27 +256,12 @@ static void cleanup_net(struct work_struct *work)
synchronize_rcu();
/* Run all of the network namespace exit methods */
list_for_each_entry_reverse(ops, &pernet_list, list) {
if (ops->exit) {
list_for_each_entry(net, &net_kill_list, cleanup_list)
ops->exit(net);
}
if (&ops->list == first_device) {
LIST_HEAD(dev_kill_list);
rtnl_lock();
list_for_each_entry(net, &net_kill_list, cleanup_list)
unregister_netdevices(net, &dev_kill_list);
unregister_netdevice_many(&dev_kill_list);
rtnl_unlock();
}
}
list_for_each_entry_reverse(ops, &pernet_list, list)
ops_exit_list(ops, &net_exit_list);
/* Free the net generic variables */
list_for_each_entry_reverse(ops, &pernet_list, list) {
if (ops->size && ops->id) {
list_for_each_entry(net, &net_kill_list, cleanup_list)
ops_free(ops, net);
}
}
list_for_each_entry_reverse(ops, &pernet_list, list)
ops_free_list(ops, &net_exit_list);
mutex_unlock(&net_mutex);
@ -259,8 +271,8 @@ static void cleanup_net(struct work_struct *work)
rcu_barrier();
/* Finally it is safe to free my network namespace structure */
list_for_each_entry_safe(net, tmp, &net_kill_list, cleanup_list) {
list_del_init(&net->cleanup_list);
list_for_each_entry_safe(net, tmp, &net_exit_list, exit_list) {
list_del_init(&net->exit_list);
net_free(net);
}
}
@ -348,8 +360,9 @@ pure_initcall(net_ns_init);
static int __register_pernet_operations(struct list_head *list,
struct pernet_operations *ops)
{
struct net *net, *undo_net;
struct net *net;
int error;
LIST_HEAD(net_exit_list);
list_add_tail(&ops->list, list);
if (ops->init || (ops->id && ops->size)) {
@ -357,6 +370,7 @@ static int __register_pernet_operations(struct list_head *list,
error = ops_init(ops, net);
if (error)
goto out_undo;
list_add_tail(&net->exit_list, &net_exit_list);
}
}
return 0;
@ -364,36 +378,21 @@ static int __register_pernet_operations(struct list_head *list,
out_undo:
/* If I have an error cleanup all namespaces I initialized */
list_del(&ops->list);
if (ops->exit) {
for_each_net(undo_net) {
if (net_eq(undo_net, net))
goto undone;
ops->exit(undo_net);
}
}
undone:
if (ops->size && ops->id) {
for_each_net(undo_net) {
if (net_eq(undo_net, net))
goto freed;
ops_free(ops, undo_net);
}
}
freed:
ops_exit_list(ops, &net_exit_list);
ops_free_list(ops, &net_exit_list);
return error;
}
static void __unregister_pernet_operations(struct pernet_operations *ops)
{
struct net *net;
LIST_HEAD(net_exit_list);
list_del(&ops->list);
if (ops->exit)
for_each_net(net)
ops->exit(net);
if (ops->id && ops->size)
for_each_net(net)
ops_free(ops, net);
for_each_net(net)
list_add_tail(&net->exit_list, &net_exit_list);
ops_exit_list(ops, &net_exit_list);
ops_free_list(ops, &net_exit_list);
}
#else
@ -411,9 +410,10 @@ static int __register_pernet_operations(struct list_head *list,
static void __unregister_pernet_operations(struct pernet_operations *ops)
{
if (ops->exit)
ops->exit(&init_net);
ops_free(ops, &init_net);
LIST_HEAD(net_exit_list);
list_add(&init_net.exit_list, &net_exit_list);
ops_exit_list(ops, &net_exit_list);
ops_free_list(ops, &net_exit_list);
}
#endif /* CONFIG_NET_NS */