mac80211: track master queue status

This is a preparation for the dynamic power save support. In future there are
two paths to stop the master queues and we need to track this properly to
avoid starting queues incorrectly. Implement this by adding a status
array for each queue.

The original idea and design is from Johannes Berg, I just did
the implementation based on his notes. All the bugs are mine, of course.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 80 insertions, 6 deletions

diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 71a8391c54f6..fb89e1d0aa03 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -330,10 +330,20 @@ __le16 ieee80211_ctstoself_duration(struct ieee80211_hw *hw,
 }
 EXPORT_SYMBOL(ieee80211_ctstoself_duration);
 
-void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
+static void __ieee80211_wake_queue(struct ieee80211_hw *hw, int queue,
+                                   enum queue_stop_reason reason)
 {
         struct ieee80211_local *local = hw_to_local(hw);
 
+        /* we don't need to track ampdu queues */
+        if (queue < ieee80211_num_regular_queues(hw)) {
+                __clear_bit(reason, &local->queue_stop_reasons[queue]);
+
+                if (local->queue_stop_reasons[queue] != 0)
+                        /* someone still has this queue stopped */
+                        return;
+        }
+
         if (test_bit(queue, local->queues_pending)) {
                 set_bit(queue, local->queues_pending_run);
                 tasklet_schedule(&local->tx_pending_tasklet);
@@ -341,22 +351,74 @@ void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
                 netif_wake_subqueue(local->mdev, queue);
         }
 }
+
+void ieee80211_wake_queue_by_reason(struct ieee80211_hw *hw, int queue,
+                                    enum queue_stop_reason reason)
+{
+        struct ieee80211_local *local = hw_to_local(hw);
+        unsigned long flags;
+
+        spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+        __ieee80211_wake_queue(hw, queue, reason);
+        spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+}
+
+void ieee80211_wake_queue(struct ieee80211_hw *hw, int queue)
+{
+        ieee80211_wake_queue_by_reason(hw, queue,
+                                       IEEE80211_QUEUE_STOP_REASON_DRIVER);
+}
 EXPORT_SYMBOL(ieee80211_wake_queue);
 
-void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
+static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue,
+                                   enum queue_stop_reason reason)
 {
         struct ieee80211_local *local = hw_to_local(hw);
 
+        /* we don't need to track ampdu queues */
+        if (queue < ieee80211_num_regular_queues(hw))
+                __set_bit(reason, &local->queue_stop_reasons[queue]);
+
         netif_stop_subqueue(local->mdev, queue);
 }
+
+void ieee80211_stop_queue_by_reason(struct ieee80211_hw *hw, int queue,
+                                    enum queue_stop_reason reason)
+{
+        struct ieee80211_local *local = hw_to_local(hw);
+        unsigned long flags;
+
+        spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+        __ieee80211_stop_queue(hw, queue, reason);
+        spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+}
+
+void ieee80211_stop_queue(struct ieee80211_hw *hw, int queue)
+{
+        ieee80211_stop_queue_by_reason(hw, queue,
+                                       IEEE80211_QUEUE_STOP_REASON_DRIVER);
+}
 EXPORT_SYMBOL(ieee80211_stop_queue);
 
-void ieee80211_stop_queues(struct ieee80211_hw *hw)
+void ieee80211_stop_queues_by_reason(struct ieee80211_hw *hw,
+                                    enum queue_stop_reason reason)
 {
+        struct ieee80211_local *local = hw_to_local(hw);
+        unsigned long flags;
         int i;
 
+        spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+
         for (i = 0; i < ieee80211_num_queues(hw); i++)
-                ieee80211_stop_queue(hw, i);
+                __ieee80211_stop_queue(hw, i, reason);
+
+        spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+}
+
+void ieee80211_stop_queues(struct ieee80211_hw *hw)
+{
+        ieee80211_stop_queues_by_reason(hw,
+                                        IEEE80211_QUEUE_STOP_REASON_DRIVER);
 }
 EXPORT_SYMBOL(ieee80211_stop_queues);
 
@@ -367,12 +429,24 @@ int ieee80211_queue_stopped(struct ieee80211_hw *hw, int queue)
 }
 EXPORT_SYMBOL(ieee80211_queue_stopped);
 
-void ieee80211_wake_queues(struct ieee80211_hw *hw)
+void ieee80211_wake_queues_by_reason(struct ieee80211_hw *hw,
+                                     enum queue_stop_reason reason)
 {
+        struct ieee80211_local *local = hw_to_local(hw);
+        unsigned long flags;
         int i;
 
+        spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+
         for (i = 0; i < hw->queues + hw->ampdu_queues; i++)
-                ieee80211_wake_queue(hw, i);
+                __ieee80211_wake_queue(hw, i, reason);
+
+        spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+}
+
+void ieee80211_wake_queues(struct ieee80211_hw *hw)
+{
+        ieee80211_wake_queues_by_reason(hw, IEEE80211_QUEUE_STOP_REASON_DRIVER);
 }
 EXPORT_SYMBOL(ieee80211_wake_queues);