+#ifdef CONFIG_PROC_FS
+#define PROTO_INUSE_NR 64 /* should be enough for the first time */
+struct prot_inuse {
+ int val[PROTO_INUSE_NR];
+};
+
+static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
+
+#ifdef CONFIG_NET_NS
+void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
+{
+ int cpu = smp_processor_id();
+ per_cpu_ptr(net->core.inuse, cpu)->val[prot->inuse_idx] += val;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
+
+int sock_prot_inuse_get(struct net *net, struct proto *prot)
+{
+ int cpu, idx = prot->inuse_idx;
+ int res = 0;
+
+ for_each_possible_cpu(cpu)
+ res += per_cpu_ptr(net->core.inuse, cpu)->val[idx];
+
+ return res >= 0 ? res : 0;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
+
+static int sock_inuse_init_net(struct net *net)
+{
+ net->core.inuse = alloc_percpu(struct prot_inuse);
+ return net->core.inuse ? 0 : -ENOMEM;
+}
+
+static void sock_inuse_exit_net(struct net *net)
+{
+ free_percpu(net->core.inuse);
+}
+
+static struct pernet_operations net_inuse_ops = {
+ .init = sock_inuse_init_net,
+ .exit = sock_inuse_exit_net,
+};
+
+static __init int net_inuse_init(void)
+{
+ if (register_pernet_subsys(&net_inuse_ops))
+ panic("Cannot initialize net inuse counters");
+
+ return 0;
+}
+
+core_initcall(net_inuse_init);
+#else
+static DEFINE_PER_CPU(struct prot_inuse, prot_inuse);
+
+void sock_prot_inuse_add(struct net *net, struct proto *prot, int val)
+{
+ __get_cpu_var(prot_inuse).val[prot->inuse_idx] += val;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_add);
+
+int sock_prot_inuse_get(struct net *net, struct proto *prot)
+{
+ int cpu, idx = prot->inuse_idx;
+ int res = 0;
+
+ for_each_possible_cpu(cpu)
+ res += per_cpu(prot_inuse, cpu).val[idx];
+
+ return res >= 0 ? res : 0;
+}
+EXPORT_SYMBOL_GPL(sock_prot_inuse_get);
+#endif
+
+static void assign_proto_idx(struct proto *prot)
+{
+ prot->inuse_idx = find_first_zero_bit(proto_inuse_idx, PROTO_INUSE_NR);
+
+ if (unlikely(prot->inuse_idx == PROTO_INUSE_NR - 1)) {
+ printk(KERN_ERR "PROTO_INUSE_NR exhausted\n");
+ return;
+ }
+
+ set_bit(prot->inuse_idx, proto_inuse_idx);
+}
+
+static void release_proto_idx(struct proto *prot)
+{
+ if (prot->inuse_idx != PROTO_INUSE_NR - 1)
+ clear_bit(prot->inuse_idx, proto_inuse_idx);
+}
+#else
+static inline void assign_proto_idx(struct proto *prot)
+{
+}
+
+static inline void release_proto_idx(struct proto *prot)
+{
+}
+#endif
+