When the rate control algorithms are built-in, their exit
functions can be called from mac80211's init function so
they cannot be marked __exit.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Acked-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix last_sample initialization. kzalloc'ing the per-STA data wasn't enough,
as jiffies can assume negative values as well. This fixes a bug which
prevented correct PID operation for a while after booting.

Thanks to Michael Buesch for reporting this.
Reported-and-tested-by: NMichael Buesch <mb@bu3sch.de>
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Mattias Nissler's "clean up rate selection" patch incorrectly changes
the behavior of txrate setting in sta_info. This patch backs out parts
of the rate selection consolidation in order to fix this issue for now.
Signed-off-by: NMichael Wu <flamingice@sourmilk.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

I would argue that mac80211 should handle fixed rates outside the rate
control code, which would also allow them to take effect immediately
instead of during the rate control callback, but this is pretty close
to correct.
Signed-Off-By: NAndy Lutomirski <luto@myrealbox.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch changes mac80211's Kconfig/Makefile to:
 * select between the PID and the SIMPLE rate control
   algorithm as default
 * always allow tri-state for the rate control algorithms,
   building those that are selected 'y' into the mac80211
   module (if that is a module, otherwise all into the kernel)
 * force the default rate control algorithm to be built into
   mac80211

It also makes both rate control algorithms proper modules again
with MODULE_LICENSE etc.

Only if EMBEDDED is the user allowed to select "NONE" as default
which will cause no algorithm to be selected, this will work
only when the driver brings one itself (e.g. iwlwifi drivers).
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix a bug which caused uncorrect refcounting of PHYs in mac80211. Thanks to
Johannes Berg for spotting this out.

Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Simplify and fix rate_control_pid_shift_adjust(). A bug prevented correct
mapping of sorted rates, and readability was seriously flawed.
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Export the non-shifted target_pf value to debugfs, so that it's human-readable.
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds all the tunable parameters used by rc80211_pid to debugfs for easy
testing and tuning.
Signed-off-by: NMattias Nissler <mattias.nissler@gmx.de>
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds a new debugfs file from which rate control relevant events can be
read one event per line. The output includes the current time, so graphs can be
created showing the rate control parameters. This helps in evaluating and
tuning rate control parameters. While at it, we split headers and code for
better readability.
Signed-off-by: NMattias Nissler <mattias.nissler@gmx.de>
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces a PID sharpening factor for faster response after
association and low activity events.
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NMattias Nissler <mattias.nissler@gmx.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces a learning algorithm in order for the PID controller
to learn how to map adjustment values to rates. This is better described in
code comments.
Signed-off-by: NStefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a new rate control algorithm based on a PID controller. It samples the
percentage of failed frames over time, feeds the result into the controller and
uses its output to control the TX rate.
Signed-off-by: NMattias Nissler <mattias.nissler@gmx.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>