mac80211: add PID controller based rate control algorithm

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: Mattias Nissler <mattias.nissler@gmx.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 22 insertions, 5 deletions

diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c
index 5bf7a5bebfc9..3d7b4341914e 100644
--- a/net/mac80211/ieee80211.c
+++ b/net/mac80211/ieee80211.c
@@ -1315,23 +1315,37 @@ static int __init ieee80211_init(void)
 #ifdef CONFIG_MAC80211_RCSIMPLE
         ret = ieee80211_rate_control_register(&mac80211_rcsimple);
         if (ret)
-                return ret;
+                goto fail;
+#endif
+
+#ifdef CONFIG_MAC80211_RCPID
+        ret = ieee80211_rate_control_register(&mac80211_rcpid);
+        if (ret)
+                goto fail;
 #endif
 
         ret = ieee80211_wme_register();
         if (ret) {
-#ifdef CONFIG_MAC80211_RCSIMPLE
-                ieee80211_rate_control_unregister(&mac80211_rcsimple);
-#endif
                 printk(KERN_DEBUG "ieee80211_init: failed to "
                        "initialize WME (err=%d)\n", ret);
-                return ret;
+                goto fail;
         }
 
         ieee80211_debugfs_netdev_init();
         ieee80211_regdomain_init();
 
         return 0;
+
+fail:
+
+#ifdef CONFIG_MAC80211_RCSIMPLE
+        ieee80211_rate_control_unregister(&mac80211_rcsimple);
+#endif
+#ifdef CONFIG_MAC80211_RCPID
+        ieee80211_rate_control_unregister(&mac80211_rcpid);
+#endif
+
+        return ret;
 }
 
 static void __exit ieee80211_exit(void)
@@ -1339,6 +1353,9 @@ static void __exit ieee80211_exit(void)
 #ifdef CONFIG_MAC80211_RCSIMPLE
         ieee80211_rate_control_unregister(&mac80211_rcsimple);
 #endif
+#ifdef CONFIG_MAC80211_RCPID
+        ieee80211_rate_control_unregister(&mac80211_rcpid);
+#endif
 
         ieee80211_wme_unregister();
         ieee80211_debugfs_netdev_exit();