Merge branch 'next' of ssh://master.kernel.org/pub/scm/linux/kernel/git/jwboyer/power...

[linux-2.6-omap-h63xx.git] / net / dccp / ccids / Kconfig

diff --git a/net/dccp/ccids/Kconfig b/net/dccp/ccids/Kconfig
index 8533dabfb9f8200468dd3d18b88436cfd969f00a..12275943eab8fae852664b3adba29ecb54415f24 100644 (file)
--- a/net/dccp/ccids/Kconfig
+++ b/net/dccp/ccids/Kconfig
@@ -1,9 +1,8 @@
 menu "DCCP CCIDs Configuration (EXPERIMENTAL)"
-       depends on IP_DCCP && EXPERIMENTAL
+       depends on EXPERIMENTAL
 
 config IP_DCCP_CCID2
        tristate "CCID2 (TCP-Like) (EXPERIMENTAL)"
-       depends on IP_DCCP
        def_tristate IP_DCCP
        select IP_DCCP_ACKVEC
        ---help---
@@ -20,28 +19,26 @@ config IP_DCCP_CCID2
          to the user.  For example, a hypothetical application that
          transferred files over DCCP, using application-level retransmissions
          for lost packets, would prefer CCID 2 to CCID 3.  On-line games may
-         also prefer CCID 2.
+         also prefer CCID 2.  See RFC 4341 for further details.
 
-         CCID 2 is further described in RFC 4341,
-         http://www.ietf.org/rfc/rfc4341.txt
-
-         This text was extracted from RFC 4340 (sec. 10.1),
-         http://www.ietf.org/rfc/rfc4340.txt
-
-         If in doubt, say M.
+         CCID2 is the default CCID used by DCCP.
 
 config IP_DCCP_CCID2_DEBUG
-         bool "CCID2 debug"
+         bool "CCID2 debugging messages"
          depends on IP_DCCP_CCID2
          ---help---
-           Enable CCID2 debug messages.
+           Enable CCID2-specific debugging messages.
+
+           When compiling CCID2 as a module, this debugging output can
+           additionally be toggled by setting the ccid2_debug module
+           parameter to 0 or 1.
 
            If in doubt, say N.
 
 config IP_DCCP_CCID3
        tristate "CCID3 (TCP-Friendly) (EXPERIMENTAL)"
-       depends on IP_DCCP
        def_tristate IP_DCCP
+       select IP_DCCP_TFRC_LIB
        ---help---
          CCID 3 denotes TCP-Friendly Rate Control (TFRC), an equation-based
          rate-controlled congestion control mechanism.  TFRC is designed to
@@ -62,10 +59,61 @@ config IP_DCCP_CCID3
          This text was extracted from RFC 4340 (sec. 10.2),
          http://www.ietf.org/rfc/rfc4340.txt
          
+         To compile this CCID as a module, choose M here: the module will be
+         called dccp_ccid3.
+
          If in doubt, say M.
 
+config IP_DCCP_CCID3_DEBUG
+         bool "CCID3 debugging messages"
+         depends on IP_DCCP_CCID3
+         ---help---
+           Enable CCID3-specific debugging messages.
+
+           When compiling CCID3 as a module, this debugging output can
+           additionally be toggled by setting the ccid3_debug module
+           parameter to 0 or 1.
+
+           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
-       depends on IP_DCCP_CCID3
-       def_tristate IP_DCCP_CCID3
+       tristate
+       default n
+
+config IP_DCCP_TFRC_DEBUG
+       bool
+       depends on IP_DCCP_TFRC_LIB
+       default y if IP_DCCP_CCID3_DEBUG
 
 endmenu