From: Tonghao Zhang <xiangxia.m....@gmail.com> Date: Mon, 12 Feb 2018 18:44:00 -0800
> Sometimes, we want to know how many tcp sockets are in use > different _net_ namespaces. It's a key resource metric. With > this patch, we can get it via /proc/net/sockstat. > > The 'alloc' show in /proc/net/sockstat is the total tcp > sockets in the kernel. This patch moves it to namespace, > via adding a counter because the previous counter is used > in proto(e.g tcp, udp and sctp) memory management. > > Signed-off-by: Tonghao Zhang <xiangxia.m....@gmail.com> ... > @@ -453,6 +453,8 @@ void tcp_init_sock(struct sock *sk) > sk->sk_rcvbuf = sock_net(sk)->ipv4.sysctl_tcp_rmem[1]; > > sk_sockets_allocated_inc(sk); > + if (likely(sk->sk_net_refcnt)) > + tcp_sock_allocated_add(sock_net(sk), 1); > } > EXPORT_SYMBOL(tcp_init_sock); > ... > @@ -1928,6 +1928,8 @@ void tcp_v4_destroy_sock(struct sock *sk) > tcp_saved_syn_free(tp); > > sk_sockets_allocated_dec(sk); > + if (likely(sk->sk_net_refcnt)) > + tcp_sock_allocated_add(sock_net(sk), -1); > } > EXPORT_SYMBOL(tcp_v4_destroy_sock); > ... > @@ -559,6 +559,9 @@ struct sock *tcp_create_openreq_child(const struct sock > *sk, > newtp->rack.reo_wnd_persist = 0; > newtp->rack.dsack_seen = 0; > > + if (likely(newsk->sk_net_refcnt)) > + tcp_sock_allocated_add(sock_net(newsk), 1); > + > __TCP_INC_STATS(sock_net(sk), TCP_MIB_PASSIVEOPENS); The amount of new conditional tests in these fast paths are not justified for this new counter which is of debatable usefullness. I'm not applying this, sorry.
