On Thu, 2017-12-07 at 08:45 -0800, Tonghao Zhang wrote: > In some case, we want to know how many sockets are in use in > different _net_ namespaces. It's a key resource metric. >
... > +static void sock_inuse_add(struct net *net, int val) > +{ > + if (net->core.prot_inuse) > + this_cpu_add(*net->core.sock_inuse, val); > +} This is very confusing. Why testing net->core.prot_inuse for NULL is needed at all ? Why not testing net->core.sock_inuse instead ?