From 09ad9bc752519cc167d0a573e1acf69b5c707c67 Mon Sep 17 00:00:00 2001 From: Octavian Purdila Date: Wed, 25 Nov 2009 15:14:13 -0800 Subject: net: use net_eq to compare nets Generated with the following semantic patch @@ struct net *n1; struct net *n2; @@ - n1 == n2 + net_eq(n1, n2) @@ struct net *n1; struct net *n2; @@ - n1 != n2 + !net_eq(n1, n2) applied over {include,net,drivers/net}. Signed-off-by: Octavian Purdila Signed-off-by: David S. Miller --- net/core/net_namespace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 1c1af2756f3..86ed7f44d08 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -280,7 +280,7 @@ out_undo: list_del(&ops->list); if (ops->exit) { for_each_net(undo_net) { - if (undo_net == net) + if (net_eq(undo_net, net)) goto undone; ops->exit(undo_net); } -- cgit v1.2.3-18-g5258 From 2b035b39970740722598f7a9d548835f9bdd730f Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Sun, 29 Nov 2009 22:25:27 +0000 Subject: net: Batch network namespace destruction. It is fairly common to kill several network namespaces at once. Either because they are nested one inside the other or because they are cooperating in multiple machine networking experiments. As the network stack control logic does not parallelize easily batch up multiple network namespaces existing together. To get the full benefit of batching the virtual network devices to be removed must be all removed in one batch. For that purpose I have added a loop after the last network device operations have run that batches up all remaining network devices and deletes them. An extra benefit is that the reorganization slightly shrinks the size of the per network namespace data structures replaceing a work_struct with a list_head. In a trivial test with 4K namespaces this change reduced the cost of a destroying 4K namespaces from 7+ minutes (at 12% cpu) to 44 seconds (at 60% cpu). The bulk of that 44s was spent in inet_twsk_purge. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller --- net/core/net_namespace.c | 66 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 58 insertions(+), 8 deletions(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 86ed7f44d08..a42caa2b909 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -8,8 +8,10 @@ #include #include #include +#include #include #include +#include /* * Our network namespace constructor/destructor lists @@ -27,6 +29,20 @@ EXPORT_SYMBOL(init_net); #define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */ +static void unregister_netdevices(struct net *net, struct list_head *list) +{ + struct net_device *dev; + /* At exit all network devices most be removed from a network + * namespace. Do this in the reverse order of registeration. + */ + for_each_netdev_reverse(net, dev) { + if (dev->rtnl_link_ops) + dev->rtnl_link_ops->dellink(dev, list); + else + unregister_netdevice_queue(dev, list); + } +} + /* * setup_net runs the initializers for the network namespace object. */ @@ -59,6 +75,13 @@ out_undo: 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(); + } } rcu_barrier(); @@ -147,18 +170,26 @@ struct net *copy_net_ns(unsigned long flags, struct net *old_net) return net_create(); } +static DEFINE_SPINLOCK(cleanup_list_lock); +static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */ + static void cleanup_net(struct work_struct *work) { struct pernet_operations *ops; - struct net *net; + struct net *net, *tmp; + LIST_HEAD(net_kill_list); - net = container_of(work, struct net, work); + /* Atomically snapshot the list of namespaces to cleanup */ + spin_lock_irq(&cleanup_list_lock); + list_replace_init(&cleanup_list, &net_kill_list); + spin_unlock_irq(&cleanup_list_lock); mutex_lock(&net_mutex); /* Don't let anyone else find us. */ rtnl_lock(); - list_del_rcu(&net->list); + list_for_each_entry(net, &net_kill_list, cleanup_list) + list_del_rcu(&net->list); rtnl_unlock(); /* @@ -170,8 +201,18 @@ static void cleanup_net(struct work_struct *work) /* Run all of the network namespace exit methods */ list_for_each_entry_reverse(ops, &pernet_list, list) { - if (ops->exit) - ops->exit(net); + 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(); + } } mutex_unlock(&net_mutex); @@ -182,14 +223,23 @@ static void cleanup_net(struct work_struct *work) rcu_barrier(); /* Finally it is safe to free my network namespace structure */ - net_free(net); + list_for_each_entry_safe(net, tmp, &net_kill_list, cleanup_list) { + list_del_init(&net->cleanup_list); + net_free(net); + } } +static DECLARE_WORK(net_cleanup_work, cleanup_net); void __put_net(struct net *net) { /* Cleanup the network namespace in process context */ - INIT_WORK(&net->work, cleanup_net); - queue_work(netns_wq, &net->work); + unsigned long flags; + + spin_lock_irqsave(&cleanup_list_lock, flags); + list_add(&net->cleanup_list, &cleanup_list); + spin_unlock_irqrestore(&cleanup_list_lock, flags); + + queue_work(netns_wq, &net_cleanup_work); } EXPORT_SYMBOL_GPL(__put_net); -- cgit v1.2.3-18-g5258 From f875bae065334907796da12523f9df85c89f5712 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Sun, 29 Nov 2009 22:25:28 +0000 Subject: net: Automatically allocate per namespace data. To get the full benefit of batched network namespace cleanup netowrk device deletion needs to be performed by the generic code. When using register_pernet_gen_device and freeing the data in exit_net it is impossible to delay allocation until after exit_net has called as the device uninit methods are no longer safe. To correct this, and to simplify working with per network namespace data I have moved allocation and deletion of per network namespace data into the network namespace core. The core now frees the data only after all of the network namespace exit routines have run. Now it is only required to set the new fields .id and .size in the pernet_operations structure if you want network namespace data to be managed for you automatically. This makes the current register_pernet_gen_device and register_pernet_gen_subsys routines unnecessary. For the moment I have left them as compatibility wrappers in net_namespace.h They will be removed once all of the users have been updated. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller --- net/core/net_namespace.c | 188 +++++++++++++++++++++++++---------------------- 1 file changed, 102 insertions(+), 86 deletions(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index a42caa2b909..9679ad292da 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -43,13 +43,40 @@ static void unregister_netdevices(struct net *net, struct list_head *list) } } +static int ops_init(const struct pernet_operations *ops, struct net *net) +{ + int err; + if (ops->id && ops->size) { + void *data = kzalloc(ops->size, GFP_KERNEL); + if (!data) + return -ENOMEM; + + err = net_assign_generic(net, *ops->id, data); + if (err) { + kfree(data); + return err; + } + } + if (ops->init) + return ops->init(net); + return 0; +} + +static void ops_free(const struct pernet_operations *ops, struct net *net) +{ + if (ops->id && ops->size) { + int id = *ops->id; + kfree(net_generic(net, id)); + } +} + /* * setup_net runs the initializers for the network namespace object. */ static __net_init int setup_net(struct net *net) { /* Must be called with net_mutex held */ - struct pernet_operations *ops; + const struct pernet_operations *ops, *saved_ops; int error = 0; atomic_set(&net->count, 1); @@ -59,11 +86,9 @@ static __net_init int setup_net(struct net *net) #endif list_for_each_entry(ops, &pernet_list, list) { - if (ops->init) { - error = ops->init(net); - if (error < 0) - goto out_undo; - } + error = ops_init(ops, net); + if (error < 0) + goto out_undo; } out: return error; @@ -72,6 +97,7 @@ out_undo: /* Walk through the list backwards calling the exit functions * for the pernet modules whose init functions did not fail. */ + saved_ops = ops; list_for_each_entry_continue_reverse(ops, &pernet_list, list) { if (ops->exit) ops->exit(net); @@ -83,6 +109,9 @@ out_undo: rtnl_unlock(); } } + ops = saved_ops; + list_for_each_entry_continue_reverse(ops, &pernet_list, list) + ops_free(ops, net); rcu_barrier(); goto out; @@ -175,7 +204,7 @@ static LIST_HEAD(cleanup_list); /* Must hold cleanup_list_lock to touch */ static void cleanup_net(struct work_struct *work) { - struct pernet_operations *ops; + const struct pernet_operations *ops; struct net *net, *tmp; LIST_HEAD(net_kill_list); @@ -214,6 +243,13 @@ static void cleanup_net(struct work_struct *work) rtnl_unlock(); } } + /* 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); + } + } mutex_unlock(&net_mutex); @@ -309,16 +345,16 @@ static int __init net_ns_init(void) pure_initcall(net_ns_init); #ifdef CONFIG_NET_NS -static int register_pernet_operations(struct list_head *list, - struct pernet_operations *ops) +static int __register_pernet_operations(struct list_head *list, + struct pernet_operations *ops) { struct net *net, *undo_net; int error; list_add_tail(&ops->list, list); - if (ops->init) { + if (ops->init || (ops->id && ops->size)) { for_each_net(net) { - error = ops->init(net); + error = ops_init(ops, net); if (error) goto out_undo; } @@ -336,10 +372,18 @@ out_undo: } } 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: return error; } -static void unregister_pernet_operations(struct pernet_operations *ops) +static void __unregister_pernet_operations(struct pernet_operations *ops) { struct net *net; @@ -347,27 +391,66 @@ static void unregister_pernet_operations(struct pernet_operations *ops) if (ops->exit) for_each_net(net) ops->exit(net); + if (ops->id && ops->size) + for_each_net(net) + ops_free(ops, net); } #else -static int register_pernet_operations(struct list_head *list, - struct pernet_operations *ops) +static int __register_pernet_operations(struct list_head *list, + struct pernet_operations *ops) { - if (ops->init == NULL) - return 0; - return ops->init(&init_net); + int err = 0; + err = ops_init(ops, &init_net); + if (err) + ops_free(ops, &init_net); + return err; + } -static void unregister_pernet_operations(struct pernet_operations *ops) +static void __unregister_pernet_operations(struct pernet_operations *ops) { if (ops->exit) ops->exit(&init_net); + ops_free(ops, &init_net); } -#endif + +#endif /* CONFIG_NET_NS */ static DEFINE_IDA(net_generic_ids); +static int register_pernet_operations(struct list_head *list, + struct pernet_operations *ops) +{ + int error; + + if (ops->id) { +again: + error = ida_get_new_above(&net_generic_ids, 1, ops->id); + if (error < 0) { + if (error == -EAGAIN) { + ida_pre_get(&net_generic_ids, GFP_KERNEL); + goto again; + } + return error; + } + } + error = __register_pernet_operations(list, ops); + if (error && ops->id) + ida_remove(&net_generic_ids, *ops->id); + + return error; +} + +static void unregister_pernet_operations(struct pernet_operations *ops) +{ + + __unregister_pernet_operations(ops); + if (ops->id) + ida_remove(&net_generic_ids, *ops->id); +} + /** * register_pernet_subsys - register a network namespace subsystem * @ops: pernet operations structure for the subsystem @@ -414,38 +497,6 @@ void unregister_pernet_subsys(struct pernet_operations *module) } EXPORT_SYMBOL_GPL(unregister_pernet_subsys); -int register_pernet_gen_subsys(int *id, struct pernet_operations *ops) -{ - int rv; - - mutex_lock(&net_mutex); -again: - rv = ida_get_new_above(&net_generic_ids, 1, id); - if (rv < 0) { - if (rv == -EAGAIN) { - ida_pre_get(&net_generic_ids, GFP_KERNEL); - goto again; - } - goto out; - } - rv = register_pernet_operations(first_device, ops); - if (rv < 0) - ida_remove(&net_generic_ids, *id); -out: - mutex_unlock(&net_mutex); - return rv; -} -EXPORT_SYMBOL_GPL(register_pernet_gen_subsys); - -void unregister_pernet_gen_subsys(int id, struct pernet_operations *ops) -{ - mutex_lock(&net_mutex); - unregister_pernet_operations(ops); - ida_remove(&net_generic_ids, id); - mutex_unlock(&net_mutex); -} -EXPORT_SYMBOL_GPL(unregister_pernet_gen_subsys); - /** * register_pernet_device - register a network namespace device * @ops: pernet operations structure for the subsystem @@ -477,30 +528,6 @@ int register_pernet_device(struct pernet_operations *ops) } EXPORT_SYMBOL_GPL(register_pernet_device); -int register_pernet_gen_device(int *id, struct pernet_operations *ops) -{ - int error; - mutex_lock(&net_mutex); -again: - error = ida_get_new_above(&net_generic_ids, 1, id); - if (error) { - if (error == -EAGAIN) { - ida_pre_get(&net_generic_ids, GFP_KERNEL); - goto again; - } - goto out; - } - error = register_pernet_operations(&pernet_list, ops); - if (error) - ida_remove(&net_generic_ids, *id); - else if (first_device == &pernet_list) - first_device = &ops->list; -out: - mutex_unlock(&net_mutex); - return error; -} -EXPORT_SYMBOL_GPL(register_pernet_gen_device); - /** * unregister_pernet_device - unregister a network namespace netdevice * @ops: pernet operations structure to manipulate @@ -520,17 +547,6 @@ void unregister_pernet_device(struct pernet_operations *ops) } EXPORT_SYMBOL_GPL(unregister_pernet_device); -void unregister_pernet_gen_device(int id, struct pernet_operations *ops) -{ - mutex_lock(&net_mutex); - if (&ops->list == first_device) - first_device = first_device->next; - unregister_pernet_operations(ops); - ida_remove(&net_generic_ids, id); - mutex_unlock(&net_mutex); -} -EXPORT_SYMBOL_GPL(unregister_pernet_gen_device); - static void net_generic_release(struct rcu_head *rcu) { struct net_generic *ng; -- cgit v1.2.3-18-g5258 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 --- net/core/net_namespace.c | 122 +++++++++++++++++++++++------------------------ 1 file changed, 61 insertions(+), 61 deletions(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 9679ad292da..6c7f6e04dbb 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 v1.2.3-18-g5258 From 04dc7f6be3a7b308f8545bb45772c9fb75f71aca Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 3 Dec 2009 02:29:04 +0000 Subject: net: Move network device exit batching Move network device exit batching from a special case in net_namespace.c to using common mechanisms in dev.c Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller --- net/core/net_namespace.c | 24 ------------------------ 1 file changed, 24 deletions(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 6c7f6e04dbb..4026a4cff93 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -8,10 +8,8 @@ #include #include #include -#include #include #include -#include /* * Our network namespace constructor/destructor lists @@ -29,20 +27,6 @@ EXPORT_SYMBOL(init_net); #define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */ -static void unregister_netdevices(struct net *net, struct list_head *list) -{ - struct net_device *dev; - /* At exit all network devices most be removed from a network - * namespace. Do this in the reverse order of registeration. - */ - for_each_netdev_reverse(net, dev) { - if (dev->rtnl_link_ops) - dev->rtnl_link_ops->dellink(dev, list); - else - unregister_netdevice_queue(dev, list); - } -} - static int ops_init(const struct pernet_operations *ops, struct net *net) { int err; @@ -78,14 +62,6 @@ static void ops_exit_list(const struct pernet_operations *ops, 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); } -- cgit v1.2.3-18-g5258 From 3a765edadb28cc736d185f67d1ba6bedcc85f4b9 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 3 Dec 2009 02:29:06 +0000 Subject: netns: Add an explicit rcu_barrier to unregister_pernet_{device|subsys} This allows namespace exit methods to batch work that comes requires an rcu barrier using call_rcu without having to treat the unregister_pernet_operations cases specially. Signed-off-by: Eric W. Biederman Signed-off-by: David S. Miller --- net/core/net_namespace.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'net/core/net_namespace.c') diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 4026a4cff93..bd8c4712ea2 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -413,8 +413,11 @@ again: } } error = __register_pernet_operations(list, ops); - if (error && ops->id) - ida_remove(&net_generic_ids, *ops->id); + if (error) { + rcu_barrier(); + if (ops->id) + ida_remove(&net_generic_ids, *ops->id); + } return error; } @@ -423,6 +426,7 @@ static void unregister_pernet_operations(struct pernet_operations *ops) { __unregister_pernet_operations(ops); + rcu_barrier(); if (ops->id) ida_remove(&net_generic_ids, *ops->id); } -- cgit v1.2.3-18-g5258