sctp: avoid to repeatedly declare external variables

Move the declaration for external variables to sctp.h file avoiding
to repeatedly declare them with extern keyword.
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sctp/sctp.h

@@ -166,6 +166,9 @@ void sctp_remaddr_proc_exit(struct net *net);
   */
 extern struct kmem_cache *sctp_chunk_cachep __read_mostly;
 extern struct kmem_cache *sctp_bucket_cachep __read_mostly;
+extern long sysctl_sctp_mem[3];
+extern int sysctl_sctp_rmem[3];
+extern int sysctl_sctp_wmem[3];
 
 /*
  *  Section:  Macros, externs, and inlines

net/sctp/socket.c

@@ -102,11 +102,6 @@ static int sctp_autobind(struct sock *sk);
 static void sctp_sock_migrate(struct sock *, struct sock *,
 			      struct sctp_association *, sctp_socket_type_t);
 
-extern struct kmem_cache *sctp_bucket_cachep;
-extern long sysctl_sctp_mem[3];
-extern int sysctl_sctp_rmem[3];
-extern int sysctl_sctp_wmem[3];
-
 static int sctp_memory_pressure;
 static atomic_long_t sctp_memory_allocated;
 struct percpu_counter sctp_sockets_allocated;

net/sctp/sysctl.c

@@ -58,10 +58,6 @@ static unsigned long max_autoclose_max =
 	(MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
 	? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
 
-extern long sysctl_sctp_mem[3];
-extern int sysctl_sctp_rmem[3];
-extern int sysctl_sctp_wmem[3];
-
 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
 				void __user *buffer, size_t *lenp,
 				loff_t *ppos);