2 files changed, 35 insertions, 0 deletions

diff --git a/include/net/sock.h b/include/net/sock.h
index 1c9d059223ee..abc6341f536f 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -562,6 +562,7 @@ struct proto {
 
         /* Keeping track of sockets in use */
 #ifdef CONFIG_PROC_FS
+        unsigned int            inuse_idx;
         struct pcounter         inuse;
 #endif
 
diff --git a/net/core/sock.c b/net/core/sock.c
index 3ee95060dbd0..7d2c8add5f5a 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1940,6 +1940,38 @@ EXPORT_SYMBOL(sk_common_release);
 static DEFINE_RWLOCK(proto_list_lock);
 static LIST_HEAD(proto_list);
 
+#ifdef CONFIG_PROC_FS
+#define PROTO_INUSE_NR  64      /* should be enough for the first time */
+
+static DECLARE_BITMAP(proto_inuse_idx, PROTO_INUSE_NR);
+
+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
+
 int proto_register(struct proto *prot, int alloc_slab)
 {
         char *request_sock_slab_name = NULL;
@@ -2000,6 +2032,7 @@ int proto_register(struct proto *prot, int alloc_slab)
 
         write_lock(&proto_list_lock);
         list_add(&prot->node, &proto_list);
+        assign_proto_idx(prot);
         write_unlock(&proto_list_lock);
         return 0;
 
@@ -2026,6 +2059,7 @@ EXPORT_SYMBOL(proto_register);
 void proto_unregister(struct proto *prot)
 {
         write_lock(&proto_list_lock);
+        release_proto_idx(prot);
         list_del(&prot->node);
         write_unlock(&proto_list_lock);