5 files changed, 93 insertions, 27 deletions

diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index 0927425026f1..a6cf8f6fc586 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -314,3 +314,11 @@ Why:	No in-kernel drivers will depend on it any longer.
 Who:    John W. Linville <linville@tuxdriver.com>
 
 ---------------------------
+
+What:   rc80211-simple rate control algorithm for mac80211
+When:   2.6.26
+Files:  net/mac80211/rc80211-simple.c
+Why:    This algorithm was provided for reference but always exhibited bad
+        responsiveness and performance and has some serious flaws. It has been
+        replaced by rc80211-pid.
+Who:    Stefano Brivio <stefano.brivio@polimi.it>
diff --git a/net/mac80211/Kconfig b/net/mac80211/Kconfig
index 9f8663b412d9..297f4d967e2d 100644
--- a/net/mac80211/Kconfig
+++ b/net/mac80211/Kconfig
@@ -13,29 +13,75 @@ config MAC80211
         This option enables the hardware independent IEEE 802.11
         networking stack.
 
-config MAC80211_RCSIMPLE
-        bool "'simple' rate control algorithm" if EMBEDDED
+config MAC80211_RC_DEFAULT_CHOICE
+        bool "Choose default rate control algorithm" if EMBEDDED
         default y
         depends on MAC80211
-        help
-          This option allows you to turn off the 'simple' rate
-          control algorithm in mac80211. If you do turn it off,
-          you absolutely need another rate control algorithm.
+        ---help---
+          This options enables selection of a default rate control
+          algorithm to be built into the mac80211 module.  Alternate
+          rate control algorithms might be built into the mac80211
+          module as well.
+
+choice
+        prompt "Default rate control algorithm"
+        default MAC80211_RC_DEFAULT_PID
+        depends on MAC80211 && MAC80211_RC_DEFAULT_CHOICE
+        ---help---
+          This option selects the default rate control algorithm
+          mac80211 will use. Note that this default can still be
+          overriden through the ieee80211_default_rc_algo module
+          parameter.
+
+config MAC80211_RC_DEFAULT_PID
+        bool "PID controller based rate control algorithm"
+        select MAC80211_RC_PID
+        ---help---
+          Select the PID controller based rate control as the
+          default rate control algorithm. You should choose
+          this unless you know what you are doing.
+
+config MAC80211_RC_DEFAULT_SIMPLE
+        bool "Simple rate control algorithm"
+        select MAC80211_RC_SIMPLE
+        ---help---
+          Select the simple rate control as the default rate
+          control algorithm. Note that this is a non-responsive,
+          dumb algorithm. You should choose the PID rate control
+          instead.
+
+endchoice
 
-          Say Y unless you know you will have another algorithm
-          available.
+config MAC80211_RC_DEFAULT
+        string
+        depends on MAC80211
+        default "pid" if MAC80211_RC_DEFAULT_PID
+        default "simple" if MAC80211_RC_DEFAULT_SIMPLE
+        default ""
 
-config MAC80211_RCPID
-        bool "'PID' rate control algorithm" if EMBEDDED
+config MAC80211_RC_PID
+        bool "PID controller based rate control algorithm"
         default y
         depends on MAC80211
-        help
+        ---help---
           This option enables a TX rate control algorithm for
           mac80211 that uses a PID controller to select the TX
           rate.
 
-          Say Y unless you're sure you want to use a different
-          rate control algorithm.
+          Say Y or M unless you're sure you want to use a
+          different rate control algorithm.
+
+config MAC80211_RC_SIMPLE
+        bool "Simple rate control algorithm (DEPRECATED)"
+        default n
+        depends on MAC80211
+        ---help---
+          This option enables a very simple, non-responsive TX
+          rate control algorithm. This algorithm is deprecated
+          and will be removed from the kernel in near future.
+          It has been replaced by the PID algorithm.
+
+          Say N unless you know what you are doing.
 
 config MAC80211_LEDS
         bool "Enable LED triggers"
diff --git a/net/mac80211/Makefile b/net/mac80211/Makefile
index 62c01ca099e5..a375f0477da0 100644
--- a/net/mac80211/Makefile
+++ b/net/mac80211/Makefile
@@ -3,8 +3,8 @@ obj-$(CONFIG_MAC80211) += mac80211.o
 mac80211-objs-$(CONFIG_MAC80211_LEDS) += ieee80211_led.o
 mac80211-objs-$(CONFIG_MAC80211_DEBUGFS) += debugfs.o debugfs_sta.o debugfs_netdev.o debugfs_key.o
 mac80211-objs-$(CONFIG_NET_SCHED) += wme.o
-mac80211-objs-$(CONFIG_MAC80211_RCSIMPLE) += rc80211_simple.o
-mac80211-objs-$(CONFIG_MAC80211_RCPID) += rc80211_pid.o
+mac80211-objs-$(CONFIG_MAC80211_RC_SIMPLE) += rc80211_simple.o
+mac80211-objs-$(CONFIG_MAC80211_RC_PID) += rc80211_pid.o
 
 mac80211-objs := \
         ieee80211.o \
diff --git a/net/mac80211/ieee80211.c b/net/mac80211/ieee80211.c
index 3d7b4341914e..c0dbf77547f7 100644
--- a/net/mac80211/ieee80211.c
+++ b/net/mac80211/ieee80211.c
@@ -1312,13 +1312,13 @@ static int __init ieee80211_init(void)
 
         BUILD_BUG_ON(sizeof(struct ieee80211_tx_packet_data) > sizeof(skb->cb));
 
-#ifdef CONFIG_MAC80211_RCSIMPLE
+#ifdef CONFIG_MAC80211_RC_SIMPLE
         ret = ieee80211_rate_control_register(&mac80211_rcsimple);
         if (ret)
                 goto fail;
 #endif
 
-#ifdef CONFIG_MAC80211_RCPID
+#ifdef CONFIG_MAC80211_RC_PID
         ret = ieee80211_rate_control_register(&mac80211_rcpid);
         if (ret)
                 goto fail;
@@ -1338,10 +1338,10 @@ static int __init ieee80211_init(void)
 
 fail:
 
-#ifdef CONFIG_MAC80211_RCSIMPLE
+#ifdef CONFIG_MAC80211_RC_SIMPLE
         ieee80211_rate_control_unregister(&mac80211_rcsimple);
 #endif
-#ifdef CONFIG_MAC80211_RCPID
+#ifdef CONFIG_MAC80211_RC_PID
         ieee80211_rate_control_unregister(&mac80211_rcpid);
 #endif
 
@@ -1350,10 +1350,10 @@ fail:
 
 static void __exit ieee80211_exit(void)
 {
-#ifdef CONFIG_MAC80211_RCSIMPLE
+#ifdef CONFIG_MAC80211_RC_SIMPLE
         ieee80211_rate_control_unregister(&mac80211_rcsimple);
 #endif
-#ifdef CONFIG_MAC80211_RCPID
+#ifdef CONFIG_MAC80211_RC_PID
         ieee80211_rate_control_unregister(&mac80211_rcpid);
 #endif
 
diff --git a/net/mac80211/ieee80211_rate.c b/net/mac80211/ieee80211_rate.c
index e495b0998b4d..65fc9ad615e9 100644
--- a/net/mac80211/ieee80211_rate.c
+++ b/net/mac80211/ieee80211_rate.c
@@ -21,6 +21,11 @@ struct rate_control_alg {
 static LIST_HEAD(rate_ctrl_algs);
 static DEFINE_MUTEX(rate_ctrl_mutex);
 
+static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
+module_param(ieee80211_default_rc_algo, charp, 0644);
+MODULE_PARM_DESC(ieee80211_default_rc_algo,
+                 "Default rate control algorithm for mac80211 to use");
+
 int ieee80211_rate_control_register(struct rate_control_ops *ops)
 {
         struct rate_control_alg *alg;
@@ -89,21 +94,27 @@ ieee80211_try_rate_control_ops_get(const char *name)
         return ops;
 }
 
-/* Get the rate control algorithm. If `name' is NULL, get the first
- * available algorithm. */
+/* Get the rate control algorithm. */
 static struct rate_control_ops *
 ieee80211_rate_control_ops_get(const char *name)
 {
         struct rate_control_ops *ops;
+        const char *alg_name;
 
         if (!name)
-                name = "simple";
+                alg_name = ieee80211_default_rc_algo;
+        else
+                alg_name = name;
 
-        ops = ieee80211_try_rate_control_ops_get(name);
+        ops = ieee80211_try_rate_control_ops_get(alg_name);
         if (!ops) {
-                request_module("rc80211_%s", name);
-                ops = ieee80211_try_rate_control_ops_get(name);
+                request_module("rc80211_%s", alg_name);
+                ops = ieee80211_try_rate_control_ops_get(alg_name);
         }
+        if (!ops && name)
+                /* try default if specific alg requested but not found */
+                ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
+
         return ops;
 }
 
@@ -244,3 +255,4 @@ void rate_control_deinitialize(struct ieee80211_local *local)
         local->rate_ctrl = NULL;
         rate_control_put(ref);
 }
+