3 files changed, 6 insertions, 38 deletions

diff --git a/net/dccp/ccids/Kconfig b/net/dccp/ccids/Kconfig
index 8408398cd44..0581143cb80 100644
--- a/net/dccp/ccids/Kconfig
+++ b/net/dccp/ccids/Kconfig
@@ -47,37 +47,6 @@ config IP_DCCP_CCID3_DEBUG
 
           If in doubt, say N.
 
-config IP_DCCP_CCID3_RTO
-          int "Use higher bound for nofeedback timer"
-          default 100
-          depends on IP_DCCP_CCID3 && EXPERIMENTAL
-          ---help---
-            Use higher lower bound for nofeedback timer expiration.
-
-            The TFRC nofeedback timer normally expires after the maximum of 4
-            RTTs and twice the current send interval (RFC 3448, 4.3). On LANs
-            with a small RTT this can mean a high processing load and reduced
-            performance, since then the nofeedback timer is triggered very
-            frequently.
-
-            This option enables to set a higher lower bound for the nofeedback
-            value. Values in units of milliseconds can be set here.
-
-            A value of 0 disables this feature by enforcing the value specified
-            in RFC 3448. The following values have been suggested as bounds for
-            experimental use:
-                * 16-20ms to match the typical multimedia inter-frame interval
-                * 100ms as a reasonable compromise [default]
-                * 1000ms corresponds to the lower TCP RTO bound (RFC 2988, 2.4)
-
-            The default of 100ms is a compromise between a large value for
-            efficient DCCP implementations, and a small value to avoid disrupting
-            the network in times of congestion.
-
-            The purpose of the nofeedback timer is to slow DCCP down when there
-            is serious network congestion: experimenting with larger values should
-            therefore not be performed on WANs.
-
 config IP_DCCP_TFRC_LIB
         def_bool y if IP_DCCP_CCID3
 
diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 4340672a817..278e1706932 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -460,13 +460,12 @@ done_computing_x:
         sk->sk_write_space(sk);
 
         /*
-         * Update timeout interval for the nofeedback timer.
-         * We use a configuration option to increase the lower bound.
-         * This can help avoid triggering the nofeedback timer too
-         * often ('spinning') on LANs with small RTTs.
+         * Update timeout interval for the nofeedback timer. In order to control
+         * rate halving on networks with very low RTTs (<= 1 ms), use per-route
+         * tunable RTAX_RTO_MIN value as the lower bound.
          */
-        hc->tx_t_rto = max_t(u32, 4 * hc->tx_rtt, (CONFIG_IP_DCCP_CCID3_RTO *
-                                                       (USEC_PER_SEC / 1000)));
+        hc->tx_t_rto = max_t(u32, 4 * hc->tx_rtt,
+                                  USEC_PER_SEC/HZ * tcp_rto_min(sk));
         /*
          * Schedule no feedback timer to expire in
          * max(t_RTO, 2 * s/X)  =  max(t_RTO, 2 * t_ipi)
diff --git a/net/dccp/ccids/ccid3.h b/net/dccp/ccids/ccid3.h
index b1864243be0..b7e569c22f3 100644
--- a/net/dccp/ccids/ccid3.h
+++ b/net/dccp/ccids/ccid3.h
@@ -42,7 +42,7 @@
 #include "lib/tfrc.h"
 #include "../ccid.h"
 
-/* Two seconds as per RFC 3448 4.2 */
+/* Two seconds as per RFC 5348, 4.2 */
 #define TFRC_INITIAL_TIMEOUT       (2 * USEC_PER_SEC)
 
 /* In usecs - half the scheduling granularity as per RFC3448 4.6 */