On 30.07.2020 17:30, Christian Brauner wrote:
> On Thu, Jul 30, 2020 at 02:59:25PM +0300, Kirill Tkhai wrote:
>> Currently, every type of namespaces has its own counter,
>> which is stored in ns-specific part. Say, @net has
>> struct net::count, @pid has struct pid_namespace::kref, etc.
>>
>> This patchset introduces unified counter for all types
>> of namespaces, and converts net namespace to use it first.
>>
>> Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
>> ---
>> include/linux/ns_common.h | 1 +
>> include/net/net_namespace.h | 11 ++++-------
>> net/core/net-sysfs.c | 6 +++---
>> net/core/net_namespace.c | 6 +++---
>> net/ipv4/inet_timewait_sock.c | 4 ++--
>> net/ipv4/tcp_metrics.c | 2 +-
>> 6 files changed, 14 insertions(+), 16 deletions(-)
>>
>> diff --git a/include/linux/ns_common.h b/include/linux/ns_common.h
>> index 5fbc4000358f..27db02ebdf36 100644
>> --- a/include/linux/ns_common.h
>> +++ b/include/linux/ns_common.h
>> @@ -8,6 +8,7 @@ struct ns_common {
>> atomic_long_t stashed;
>> const struct proc_ns_operations *ops;
>> unsigned int inum;
>> + refcount_t count;
>
> Hm, I wonder whether it's worth to have this addition be in a separate
> patch but probably not and even if there'd be no need to resend.
>
> Though I wonder, isn't this missing an include for refcount_t or is
> there some header-magic we're doing during pre-processing?
We have to add, I think. I'll resend with #include <linux/refcount.h>
in this file. Can I keep your Ack here on resend?
> Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx>
>
> Thanks!
> Christian
>
>> };
>>
>> #endif
>> diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
>> index 2ee5901bec7a..cb4b33d7834b 100644
>> --- a/include/net/net_namespace.h
>> +++ b/include/net/net_namespace.h
>> @@ -60,9 +60,6 @@ struct net {
>> refcount_t passive; /* To decide when the network
>> * namespace should be freed.
>> */
>> - refcount_t count; /* To decided when the network
>> - * namespace should be shut down.
>> - */
>> spinlock_t rules_mod_lock;
>>
>> unsigned int dev_unreg_count;
>> @@ -245,7 +242,7 @@ void __put_net(struct net *net);
>>
>> static inline struct net *get_net(struct net *net)
>> {
>> - refcount_inc(&net->count);
>> + refcount_inc(&net->ns.count);
>> return net;
>> }
>>
>> @@ -256,14 +253,14 @@ static inline struct net *maybe_get_net(struct net *net)
>> * exists. If the reference count is zero this
>> * function fails and returns NULL.
>> */
>> - if (!refcount_inc_not_zero(&net->count))
>> + if (!refcount_inc_not_zero(&net->ns.count))
>> net = NULL;
>> return net;
>> }
>>
>> static inline void put_net(struct net *net)
>> {
>> - if (refcount_dec_and_test(&net->count))
>> + if (refcount_dec_and_test(&net->ns.count))
>> __put_net(net);
>> }
>>
>> @@ -275,7 +272,7 @@ int net_eq(const struct net *net1, const struct net *net2)
>>
>> static inline int check_net(const struct net *net)
>> {
>> - return refcount_read(&net->count) != 0;
>> + return refcount_read(&net->ns.count) != 0;
>> }
>>
>> void net_drop_ns(void *);
>> diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
>> index 9de33b594ff2..655a88b0071c 100644
>> --- a/net/core/net-sysfs.c
>> +++ b/net/core/net-sysfs.c
>> @@ -1025,7 +1025,7 @@ net_rx_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
>> while (--i >= new_num) {
>> struct kobject *kobj = &dev->_rx[i].kobj;
>>
>> - if (!refcount_read(&dev_net(dev)->count))
>> + if (!refcount_read(&dev_net(dev)->ns.count))
>> kobj->uevent_suppress = 1;
>> if (dev->sysfs_rx_queue_group)
>> sysfs_remove_group(kobj, dev->sysfs_rx_queue_group);
>> @@ -1603,7 +1603,7 @@ netdev_queue_update_kobjects(struct net_device *dev, int old_num, int new_num)
>> while (--i >= new_num) {
>> struct netdev_queue *queue = dev->_tx + i;
>>
>> - if (!refcount_read(&dev_net(dev)->count))
>> + if (!refcount_read(&dev_net(dev)->ns.count))
>> queue->kobj.uevent_suppress = 1;
>> #ifdef CONFIG_BQL
>> sysfs_remove_group(&queue->kobj, &dql_group);
>> @@ -1850,7 +1850,7 @@ void netdev_unregister_kobject(struct net_device *ndev)
>> {
>> struct device *dev = &ndev->dev;
>>
>> - if (!refcount_read(&dev_net(ndev)->count))
>> + if (!refcount_read(&dev_net(ndev)->ns.count))
>> dev_set_uevent_suppress(dev, 1);
>>
>> kobject_get(&dev->kobj);
>> diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
>> index dcd61aca343e..5f658cbedd34 100644
>> --- a/net/core/net_namespace.c
>> +++ b/net/core/net_namespace.c
>> @@ -44,7 +44,7 @@ static struct key_tag init_net_key_domain = { .usage = REFCOUNT_INIT(1) };
>> #endif
>>
>> struct net init_net = {
>> - .count = REFCOUNT_INIT(1),
>> + .ns.count = REFCOUNT_INIT(1),
>> .dev_base_head = LIST_HEAD_INIT(init_net.dev_base_head),
>> #ifdef CONFIG_KEYS
>> .key_domain = &init_net_key_domain,
>> @@ -248,7 +248,7 @@ int peernet2id_alloc(struct net *net, struct net *peer, gfp_t gfp)
>> {
>> int id;
>>
>> - if (refcount_read(&net->count) == 0)
>> + if (refcount_read(&net->ns.count) == 0)
>> return NETNSA_NSID_NOT_ASSIGNED;
>>
>> spin_lock(&net->nsid_lock);
>> @@ -328,7 +328,7 @@ static __net_init int setup_net(struct net *net, struct user_namespace *user_ns)
>> int error = 0;
>> LIST_HEAD(net_exit_list);
>>
>> - refcount_set(&net->count, 1);
>> + refcount_set(&net->ns.count, 1);
>> refcount_set(&net->passive, 1);
>> get_random_bytes(&net->hash_mix, sizeof(u32));
>> net->dev_base_seq = 1;
>> diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
>> index c411c87ae865..437afe392e66 100644
>> --- a/net/ipv4/inet_timewait_sock.c
>> +++ b/net/ipv4/inet_timewait_sock.c
>> @@ -272,14 +272,14 @@ void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family)
>> continue;
>> tw = inet_twsk(sk);
>> if ((tw->tw_family != family) ||
>> - refcount_read(&twsk_net(tw)->count))
>> + refcount_read(&twsk_net(tw)->ns.count))
>> continue;
>>
>> if (unlikely(!refcount_inc_not_zero(&tw->tw_refcnt)))
>> continue;
>>
>> if (unlikely((tw->tw_family != family) ||
>> - refcount_read(&twsk_net(tw)->count))) {
>> + refcount_read(&twsk_net(tw)->ns.count))) {
>> inet_twsk_put(tw);
>> goto restart;
>> }
>> diff --git a/net/ipv4/tcp_metrics.c b/net/ipv4/tcp_metrics.c
>> index 279db8822439..39710c417565 100644
>> --- a/net/ipv4/tcp_metrics.c
>> +++ b/net/ipv4/tcp_metrics.c
>> @@ -887,7 +887,7 @@ static void tcp_metrics_flush_all(struct net *net)
>> pp = &hb->chain;
>> for (tm = deref_locked(*pp); tm; tm = deref_locked(*pp)) {
>> match = net ? net_eq(tm_net(tm), net) :
>> - !refcount_read(&tm_net(tm)->count);
>> + !refcount_read(&tm_net(tm)->ns.count);
>> if (match) {
>> *pp = tm->tcpm_next;
>> kfree_rcu(tm, rcu_head);
>>
>>
