Commit graph

5 commits

Author SHA1 Message Date
Joe Perches
f0d232080f net: mac80211: Convert printk(KERN_DEBUG to pr_debug
Standardize the debugging to be able to use dynamic_debug.

Coalesce formats, align arguments.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05 15:27:16 -04:00
Javier Cardona
6ac95b5765 mac80211: fixup for mesh TSF adjustment latency in Toffset setpoint
The original patch defined the correction margin but did not apply it.

Signed-off-by: Shinichi Hotori <hotorinn@gmail.com>
Signed-off-by: Yu Niiro <yu.niiro@gmail.com>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-04-23 15:37:41 -04:00
Javier Cardona
ec14bcd20f mac80211: Take into account TSF adjustment latency in Toffset setpoint
When testing mesh synchronization we observed a global TSF slowdown that
was dependent on the number of synchronized mesh stations.  This seems
to be caused by the TSF adjustment (read/write) latency.

Adding a small margin to the Toffset setpoint solved the problem.

Signed-off-by: Shinichi Hotori <hotorinn@gmail.com>
Signed-off-by: Yu Niiro <yu.niiro@gmail.com>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-04-16 14:19:29 -04:00
Javier Cardona
a802a6eba1 mac80211: Choose a new toffset setpoint if a big tsf jump is detected.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-04-16 14:19:29 -04:00
Javier Cardona
dbf498fbaf mac80211: Implement mesh synchronization framework
This patch adds MBSS extensible synchronization framework (Sec.
13.13.2 of IEEE Std. 802.11-2012).

The framework is implemented via an ops table which defines the
following functions:

    rx_bcn_presp() - this is called every time a mesh beacon is
received.
    adjust_tbtt() - this is called immediately before a beacon is about
to be transmitted.

The default neighbor offset synchronization defined in the standard is
implemented.  We also provide template functions for vendor specific
methods.

When neighbor offset synchronization is active (which is the default)
mesh neighbors in the same MBSS will track timing offsets to each other
and compensate clock drift.

In our tests we observed that this mesh synchronization implementation
successfully corrected drifts between stations of ~2PPM while
introducing a jitter of ~20us.

It is also possible to test this framework on mac80211_hwsim simulated
phys to see how it behaves under different topologies, over poor links,
etc.

Signed-off-by: Marco Porsch <marco.porsch@s2005.tu-chemnitz.de>
Signed-off-by: Pavel Zubarev <pavel.zubarev@gmail.com>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-04-10 15:20:31 -04:00