linux-toradex.git/net/ipv4/tcp_lp.c, branch v2.6.23.14 Linux kernel for Apalis and Colibri modules [TCP]: congestion control API pass RTT in microseconds 2007-07-31T09:27:57+00:00 Stephen Hemminger shemminger@linux-foundation.org 2007-07-26T06:49:34+00:00 30cfd0baf0a0c4329fff1ef4b622919297969ec8 This patch changes the API for the callback that is done after an ACK is received. It solves a couple of issues: * Some congestion controls want higher resolution value of RTT (controlled by TCP_CONG_RTT_SAMPLE flag). These don't really want a ktime, but all compute a RTT in microseconds. * Other congestion control could use RTT at jiffies resolution. To keep API consistent the units should be the same for both cases, just the resolution should change. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
This patch changes the API for the callback that is done after an ACK is
received. It solves a couple of issues:

  * Some congestion controls want higher resolution value of RTT
    (controlled by TCP_CONG_RTT_SAMPLE flag). These don't really want a ktime, but
    all compute a RTT in microseconds.

  * Other congestion control could use RTT at jiffies resolution.

To keep API consistent the units should be the same for both cases, just the
resolution should change.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP]: remove unused argument to cong_avoid op 2007-07-18T08:46:58+00:00 Stephen Hemminger shemminger@linux-foundation.org 2007-07-17T01:35:52+00:00 16751347a060a10c09b11593bb179fd5b0240c04 None of the existing TCP congestion controls use the rtt value pased in the ca_ops->cong_avoid interface. Which is lucky because seq_rtt could have been -1 when handling a duplicate ack. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
None of the existing TCP congestion controls use the rtt value pased
in the ca_ops->cong_avoid interface.  Which is lucky because seq_rtt
could have been -1 when handling a duplicate ack.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP]: Congestion control API RTT sampling fix 2007-06-15T22:08:43+00:00 Ilpo Järvinen ilpo.jarvinen@helsinki.fi 2007-06-15T22:08:43+00:00 b9ce204f0a265f819d10c943a607746abb62f245 Commit 164891aadf1721fca4dce473bb0e0998181537c6 broke RTT sampling of congestion control modules. Inaccurate timestamps could be fed to them without providing any way for them to identify such cases. Previously RTT sampler was called only if FLAG_RETRANS_DATA_ACKED was not set filtering inaccurate timestamps nicely. In addition, the new behavior could give an invalid timestamp (zero) to RTT sampler if only skbs with TCPCB_RETRANS were ACKed. This solves both problems. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net> 
Commit 164891aadf1721fca4dce473bb0e0998181537c6 broke RTT
sampling of congestion control modules. Inaccurate timestamps
could be fed to them without providing any way for them to
identify such cases. Previously RTT sampler was called only if
FLAG_RETRANS_DATA_ACKED was not set filtering inaccurate
timestamps nicely. In addition, the new behavior could give an
invalid timestamp (zero) to RTT sampler if only skbs with
TCPCB_RETRANS were ACKed. This solves both problems.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP]: Fix linkage errors on i386. 2007-04-26T05:29:49+00:00 YOSHIFUJI Hideaki yoshfuji@linux-ipv6.org 2007-04-24T23:21:38+00:00 84299b3bc4eaedc0734fcc9052b01291e44445fc To avoid raw division, use ktime_to_timeval() to get usec. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
To avoid raw division, use ktime_to_timeval() to get usec.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP]: Congestion control API update. 2007-04-26T05:29:45+00:00 Stephen Hemminger shemminger@linux-foundation.org 2007-04-24T05:26:16+00:00 164891aadf1721fca4dce473bb0e0998181537c6 Do some simple changes to make congestion control API faster/cleaner. * use ktime_t rather than timeval * merge rtt sampling into existing ack callback this means one indirect call versus two per ack. * use flags bits to store options/settings Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
Do some simple changes to make congestion control API faster/cleaner.
* use ktime_t rather than timeval
* merge rtt sampling into existing ack callback
  this means one indirect call versus two per ack.
* use flags bits to store options/settings

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP] tcp-lp: prevent chance for oops 2006-09-29T01:03:07+00:00 Wong Hoi Sing Edison hswong3i@gmail.com 2006-09-28T21:40:21+00:00 bfbea8a8869a0e21b97605841d04190d63665d19 This patch fix the chance for tcp_lp_remote_hz_estimator return 0, if 0 < rhz < 64. It also make sure the flag LP_VALID_RHZ is set correctly. Signed-off-by: Wong Hoi Sing Edison <hswong3i@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
This patch fix the chance for tcp_lp_remote_hz_estimator return 0, if
0 < rhz < 64. It also make sure the flag LP_VALID_RHZ is set
correctly.

Signed-off-by: Wong Hoi Sing Edison <hswong3i@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP] tcp_lp: use BUILD_BUG_ON 2006-09-22T22:18:03+00:00 Alexey Dobriyan adobriyan@gmail.com 2006-08-25T07:37:24+00:00 298969727e7b855d53f3becfa92c055914082ec4 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[NET]: Remove unnecessary config.h includes from net/ 2006-09-22T21:54:21+00:00 Dave Jones davej@redhat.com 2006-09-22T21:00:29+00:00 bf0d52492d82ad70684e17c8a46942c13d0e140e config.h is automatically included by kbuild these days. Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
config.h is automatically included by kbuild these days.

Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP] tcp-lp: bug fix for oops in 2.6.18-rc6 2006-09-18T06:21:09+00:00 Wong Hoi Sing Edison hswong3i@gmail.com 2006-09-14T03:30:30+00:00 3795da47e82ee0596174f52817d6d3ecd91f68ea Sorry that the patch submited yesterday still contain a small bug. This version have already been test for hours with BT connections. The oops is now difficult to reproduce. Signed-off-by: Wong Hoi Sing Edison <hswong3i@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Sorry that the patch submited yesterday still contain a small bug.
This version have already been test for hours with BT connections. The
oops is now difficult to reproduce.

Signed-off-by: Wong Hoi Sing Edison <hswong3i@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[TCP]: TCP Low Priority congestion control 2006-06-18T04:29:21+00:00 Wong Hoi Sing Edison hswong3i@gmail.com 2006-06-06T00:27:58+00:00 7c106d7e782bd4805f39da30e81018f861b4b8c5 TCP Low Priority is a distributed algorithm whose goal is to utilize only the excess network bandwidth as compared to the ``fair share`` of bandwidth as targeted by TCP. Available from: http://www.ece.rice.edu/~akuzma/Doc/akuzma/TCP-LP.pdf Original Author: Aleksandar Kuzmanovic <akuzma@northwestern.edu> See http://www-ece.rice.edu/networks/TCP-LP/ for their implementation. As of 2.6.13, Linux supports pluggable congestion control algorithms. Due to the limitation of the API, we take the following changes from the original TCP-LP implementation: o We use newReno in most core CA handling. Only add some checking within cong_avoid. o Error correcting in remote HZ, therefore remote HZ will be keeped on checking and updating. o Handling calculation of One-Way-Delay (OWD) within rtt_sample, sicne OWD have a similar meaning as RTT. Also correct the buggy formular. o Handle reaction for Early Congestion Indication (ECI) within pkts_acked, as mentioned within pseudo code. o OWD is handled in relative format, where local time stamp will in tcp_time_stamp format. Port from 2.4.19 to 2.6.16 as module by: Wong Hoi Sing Edison <hswong3i@gmail.com> Hung Hing Lun <hlhung3i@gmail.com> Signed-off-by: Wong Hoi Sing Edison <hswong3i@gmail.com> Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net> 
 TCP Low Priority is a distributed algorithm whose goal is to utilize only
 the excess network bandwidth as compared to the ``fair share`` of
 bandwidth as targeted by TCP. Available from:
   http://www.ece.rice.edu/~akuzma/Doc/akuzma/TCP-LP.pdf

Original Author:
 Aleksandar Kuzmanovic <akuzma@northwestern.edu>

See http://www-ece.rice.edu/networks/TCP-LP/ for their implementation.
As of 2.6.13, Linux supports pluggable congestion control algorithms.
Due to the limitation of the API, we take the following changes from
the original TCP-LP implementation:
 o We use newReno in most core CA handling. Only add some checking
   within cong_avoid.
 o Error correcting in remote HZ, therefore remote HZ will be keeped
   on checking and updating.
 o Handling calculation of One-Way-Delay (OWD) within rtt_sample, sicne
   OWD have a similar meaning as RTT. Also correct the buggy formular.
 o Handle reaction for Early Congestion Indication (ECI) within
   pkts_acked, as mentioned within pseudo code.
 o OWD is handled in relative format, where local time stamp will in
   tcp_time_stamp format.

Port from 2.4.19 to 2.6.16 as module by:
 Wong Hoi Sing Edison <hswong3i@gmail.com>
 Hung Hing Lun <hlhung3i@gmail.com>

Signed-off-by: Wong Hoi Sing Edison <hswong3i@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>