mac80211/rt2x00: add ieee80211_tx_status_ni()

All rt2x00 drivers except rt2800pci call ieee80211_tx_status() from
a workqueue, which causes "NOHZ: local_softirq_pending 08" messages.

To fix it, add ieee80211_tx_status_ni() similar to ieee80211_rx_ni()
which can be called from process context, and call it from
rt2x00lib_txdone().  For the rt2800pci special case a driver
flag is introduced.

https://bugzilla.kernel.org/show_bug.cgi?id=24892

Signed-off-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 24 insertions, 4 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 9fdf982d1286..365359b24177 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2024,8 +2024,8 @@ static inline void ieee80211_rx_ni(struct ieee80211_hw *hw,
  *
  * This function may not be called in IRQ context. Calls to this function
  * for a single hardware must be synchronized against each other. Calls
- * to this function and ieee80211_tx_status_irqsafe() may not be mixed
- * for a single hardware.
+ * to this function, ieee80211_tx_status_ni() and ieee80211_tx_status_irqsafe()
+ * may not be mixed for a single hardware.
  *
  * @hw: the hardware the frame was transmitted by
  * @skb: the frame that was transmitted, owned by mac80211 after this call
@@ -2034,13 +2034,33 @@ void ieee80211_tx_status(struct ieee80211_hw *hw,
                          struct sk_buff *skb);
 
 /**
+ * ieee80211_tx_status_ni - transmit status callback (in process context)
+ *
+ * Like ieee80211_tx_status() but can be called in process context.
+ *
+ * Calls to this function, ieee80211_tx_status() and
+ * ieee80211_tx_status_irqsafe() may not be mixed
+ * for a single hardware.
+ *
+ * @hw: the hardware the frame was transmitted by
+ * @skb: the frame that was transmitted, owned by mac80211 after this call
+ */
+static inline void ieee80211_tx_status_ni(struct ieee80211_hw *hw,
+                                          struct sk_buff *skb)
+{
+        local_bh_disable();
+        ieee80211_tx_status(hw, skb);
+        local_bh_enable();
+}
+
+/**
  * ieee80211_tx_status_irqsafe - IRQ-safe transmit status callback
  *
  * Like ieee80211_tx_status() but can be called in IRQ context
  * (internally defers to a tasklet.)
  *
- * Calls to this function and ieee80211_tx_status() may not be mixed for a
- * single hardware.
+ * Calls to this function, ieee80211_tx_status() and
+ * ieee80211_tx_status_ni() may not be mixed for a single hardware.
  *
  * @hw: the hardware the frame was transmitted by
  * @skb: the frame that was transmitted, owned by mac80211 after this call