This patch add a member in struct netns_core. And this is a counter for socket_inuse in the _net_ namespace. The patch will add/sub counter in the sk_alloc or sk_free. Because socket and sock is in pair. It's a easy way to maintain the code and help developer to review. More important, it avoids holding the _net_ namespace again.
Signed-off-by: Martin Zhang <zhangjunweimar...@didichuxing.com> Signed-off-by: Tonghao Zhang <zhangtong...@didichuxing.com> --- v3 --> v4: 1. add noop function for !CONF_PROC_FS case. 2. change the __this_cpu_add to this_cpu_add. This is reported by lkp. reported at: http://patchwork.ozlabs.org/patch/837424/ --- include/net/netns/core.h | 1 + include/net/sock.h | 1 + net/core/sock.c | 40 +++++++++++++++++++++++++++++++++++++++- net/socket.c | 13 ++----------- 4 files changed, 43 insertions(+), 12 deletions(-) diff --git a/include/net/netns/core.h b/include/net/netns/core.h index 6490b79..1de41f3 100644 --- a/include/net/netns/core.h +++ b/include/net/netns/core.h @@ -11,6 +11,7 @@ struct netns_core { int sysctl_somaxconn; struct prot_inuse __percpu *prot_inuse; + int __percpu *sock_inuse; }; #endif diff --git a/include/net/sock.h b/include/net/sock.h index 6f1be97..169a26f 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1263,6 +1263,7 @@ static inline void sk_sockets_allocated_inc(struct sock *sk) /* Called with local bh disabled */ void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc); int sock_prot_inuse_get(struct net *net, struct proto *proto); +int sock_inuse_get(struct net *net); #else static inline void sock_prot_inuse_add(struct net *net, struct proto *prot, int inc) diff --git a/net/core/sock.c b/net/core/sock.c index b899d86..04bbab1 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -145,6 +145,8 @@ static DEFINE_MUTEX(proto_list_mutex); static LIST_HEAD(proto_list); +static void sock_inuse_add(struct net *net, int val); + /** * sk_ns_capable - General socket capability test * @sk: Socket to use a capability on or through @@ -1536,6 +1538,7 @@ struct sock *sk_alloc(struct net *net, int family, gfp_t priority, if (likely(sk->sk_net_refcnt)) get_net(net); sock_net_set(sk, net); + sock_inuse_add(net, 1); refcount_set(&sk->sk_wmem_alloc, 1); mem_cgroup_sk_alloc(sk); @@ -1597,6 +1600,8 @@ void sk_destruct(struct sock *sk) static void __sk_free(struct sock *sk) { + sock_inuse_add(sock_net(sk), -1); + if (unlikely(sock_diag_has_destroy_listeners(sk) && sk->sk_net_refcnt)) sock_diag_broadcast_destroy(sk); else @@ -1665,6 +1670,7 @@ struct sock *sk_clone_lock(const struct sock *sk, const gfp_t priority) newsk->sk_backlog.head = newsk->sk_backlog.tail = NULL; newsk->sk_backlog.len = 0; + sock_inuse_add(sock_net(newsk), 1); atomic_set(&newsk->sk_rmem_alloc, 0); /* * sk_wmem_alloc set to one (see sk_free() and sock_wfree()) @@ -3060,15 +3066,43 @@ int sock_prot_inuse_get(struct net *net, struct proto *prot) } EXPORT_SYMBOL_GPL(sock_prot_inuse_get); +static void sock_inuse_add(struct net *net, int val) +{ + this_cpu_add(*net->core.sock_inuse, val); +} + +int sock_inuse_get(struct net *net) +{ + int cpu, res = 0; + + for_each_possible_cpu(cpu) + res += *per_cpu_ptr(net->core.sock_inuse, cpu); + + return res >= 0 ? res : 0; +} + +EXPORT_SYMBOL_GPL(sock_inuse_get); + static int __net_init sock_inuse_init_net(struct net *net) { net->core.prot_inuse = alloc_percpu(struct prot_inuse); - return net->core.prot_inuse ? 0 : -ENOMEM; + if (!net->core.prot_inuse) + return -ENOMEM; + + net->core.sock_inuse = alloc_percpu(int); + if (!net->core.sock_inuse) + goto out; + + return 0; +out: + free_percpu(net->core.prot_inuse); + return -ENOMEM; } static void __net_exit sock_inuse_exit_net(struct net *net) { free_percpu(net->core.prot_inuse); + free_percpu(net->core.sock_inuse); } static struct pernet_operations net_inuse_ops = { @@ -3111,6 +3145,10 @@ static inline void assign_proto_idx(struct proto *prot) static inline void release_proto_idx(struct proto *prot) { } + +static void sock_inuse_add(struct net *net, int val) +{ +} #endif static void req_prot_cleanup(struct request_sock_ops *rsk_prot) diff --git a/net/socket.c b/net/socket.c index b085f14..1bdf364 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2646,17 +2646,8 @@ static int __init sock_init(void) #ifdef CONFIG_PROC_FS void socket_seq_show(struct seq_file *seq) { - int cpu; - int counter = 0; - - for_each_possible_cpu(cpu) - counter += per_cpu(sockets_in_use, cpu); - - /* It can be negative, by the way. 8) */ - if (counter < 0) - counter = 0; - - seq_printf(seq, "sockets: used %d\n", counter); + seq_printf(seq, "sockets: used %d\n", + sock_inuse_get(seq->private)); } #endif /* CONFIG_PROC_FS */ -- 1.8.3.1
