iwlwifi: use threaded interrupt handler

With new transports coming up, move to threaded
interrupt handling now. This has the advantage
that we can use the same locking scheme with all
different transports we may need to implement.

Note that the TX path obviously still runs in a
tasklet, so some spin_lock() calls need to change
to spin_lock_bh() calls to properly lock out the
TX path.

In my test on a Calpella platform this has no
impact on throughput or latency.

Also add lockdep annotations to avoid lockups due
to catch sending synchronous commands or using
locks that connect with them from the irq thread.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-op-mode.h b/drivers/net/wireless/iwlwifi/iwl-op-mode.h
index dc792584f401..4a680019e117 100644
--- a/drivers/net/wireless/iwlwifi/iwl-op-mode.h
+++ b/drivers/net/wireless/iwlwifi/iwl-op-mode.h
@@ -113,13 +113,13 @@ struct iwl_cfg;
  *      May sleep
  * @rx: Rx notification to the op_mode. rxb is the Rx buffer itself. Cmd is the
  *      HCMD the this Rx responds to.
- *      Must be atomic and called with BH disabled.
+ *      This callback may sleep, it is called from a threaded IRQ handler.
  * @queue_full: notifies that a HW queue is full.
  *      Must be atomic and called with BH disabled.
  * @queue_not_full: notifies that a HW queue is not full any more.
  *      Must be atomic and called with BH disabled.
  * @hw_rf_kill:notifies of a change in the HW rf kill switch. True means that
- *      the radio is killed. Must be atomic.
+ *      the radio is killed. May sleep.
  * @free_skb: allows the transport layer to free skbs that haven't been
  *      reclaimed by the op_mode. This can happen when the driver is freed and
  *      there are Tx packets pending in the transport layer.
@@ -130,8 +130,7 @@ struct iwl_cfg;
  *      called with BH disabled.
  * @nic_config: configure NIC, called before firmware is started.
  *      May sleep
- * @wimax_active: invoked when WiMax becomes active.  Must be atomic and called
- *      with BH disabled.
+ * @wimax_active: invoked when WiMax becomes active. May sleep
  */
 struct iwl_op_mode_ops {
         struct iwl_op_mode *(*start)(struct iwl_trans *trans,
@@ -178,6 +177,7 @@ static inline int iwl_op_mode_rx(struct iwl_op_mode *op_mode,
                                   struct iwl_rx_cmd_buffer *rxb,
                                   struct iwl_device_cmd *cmd)
 {
+        might_sleep();
         return op_mode->ops->rx(op_mode, rxb, cmd);
 }
 
@@ -196,6 +196,7 @@ static inline void iwl_op_mode_queue_not_full(struct iwl_op_mode *op_mode,
 static inline void iwl_op_mode_hw_rf_kill(struct iwl_op_mode *op_mode,
                                           bool state)
 {
+        might_sleep();
         op_mode->ops->hw_rf_kill(op_mode, state);
 }
 
@@ -223,6 +224,7 @@ static inline void iwl_op_mode_nic_config(struct iwl_op_mode *op_mode)
 
 static inline void iwl_op_mode_wimax_active(struct iwl_op_mode *op_mode)
 {
+        might_sleep();
         op_mode->ops->wimax_active(op_mode);
 }