From 72ad937abd0a43b7cf2c557ba1f2ec75e608c516 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 3 Dec 2009 02:29:03 +0000 Subject: 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 Signed-off-by: David S. Miller --- include/net/net_namespace.h | 2 + net/core/net_namespace.c | 122 ++++++++++++++++++++++---------------------- 2 files changed, 63 insertions(+), 61 deletions(-) diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 24a8c5591f63..f307e133d14c 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -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; }; diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 9679ad292da9..6c7f6e04dbbf 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -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 @@ out_undo: /* 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 */ -- cgit v1.2.2