From 648845ab7e200993dccd3948c719c858368c91e7 Mon Sep 17 00:00:00 2001 From: Tonghao Zhang Date: Thu, 14 Dec 2017 05:51:58 -0800 Subject: sock: Move the socket inuse to namespace. In some case, we want to know how many sockets are in use in different _net_ namespaces. It's a key resource metric. This patch add a member in struct netns_core. This is a counter for socket-inuse in the _net_ namespace. The patch will add/sub counter in the sk_alloc, sk_clone_lock and __sk_free. This patch will not counter the socket created in kernel. It's not very useful for userspace to know how many kernel sockets we created. The main reasons for doing this are that: 1. When linux calls the 'do_exit' for process to exit, the functions 'exit_task_namespaces' and 'exit_task_work' will be called sequentially. 'exit_task_namespaces' may have destroyed the _net_ namespace, but 'sock_release' called in 'exit_task_work' may use the _net_ namespace if we counter the socket-inuse in sock_release. 2. socket and sock are in pair. More important, sock holds the _net_ namespace. We counter the socket-inuse in sock, for avoiding holding _net_ namespace again in socket. It's a easy way to maintain the code. Signed-off-by: Martin Zhang Signed-off-by: Tonghao Zhang Signed-off-by: David S. Miller --- include/net/netns/core.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/net/netns') diff --git a/include/net/netns/core.h b/include/net/netns/core.h index 45cfb5dc76c7..a5e8a66c57b4 100644 --- a/include/net/netns/core.h +++ b/include/net/netns/core.h @@ -11,6 +11,9 @@ struct netns_core { int sysctl_somaxconn; +#ifdef CONFIG_PROC_FS + int __percpu *sock_inuse; +#endif struct prot_inuse __percpu *prot_inuse; }; -- cgit v1.2.3