dccp: Lockless integration of CCID congestion-control plugins

Based on Arnaldo's earlier patch, this patch integrates the standardised
CCID congestion control plugins (CCID-2 and CCID-3) of DCCP with dccp.ko:

 * enables a faster connection path by eliminating the need to always go 
   through the CCID registration lock;

 * updates the implementation to use only a single array whose size equals
   the number of configured CCIDs instead of the maximum (256);

 * since the CCIDs are now fixed array elements, synchronization is no
   longer needed, simplifying use and implementation.

CCID-2 is suggested as minimum for a basic DCCP implementation (RFC 4340, 10);
CCID-3 is a standards-track CCID supported by RFC 4342 and RFC 5348.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 2 deletions

diff --git a/net/dccp/ackvec.h b/net/dccp/ackvec.h
index 4ccee030524e..569a33a79baa 100644
--- a/net/dccp/ackvec.h
+++ b/net/dccp/ackvec.h
@@ -84,7 +84,7 @@ struct dccp_ackvec_record {
 struct sock;
 struct sk_buff;
 
-#ifdef CONFIG_IP_DCCP_ACKVEC
+#ifndef ___OLD_INTERFACE_TO_BE_REMOVED___
 extern int dccp_ackvec_init(void);
 extern void dccp_ackvec_exit(void);
 
@@ -106,7 +106,7 @@ static inline int dccp_ackvec_pending(const struct dccp_ackvec *av)
 {
         return av->av_vec_len;
 }
-#else /* CONFIG_IP_DCCP_ACKVEC */
+#else /* ___OLD_INTERFACE_TO_BE_REMOVED___ */
 static inline int dccp_ackvec_init(void)
 {
         return 0;