[Bluetooth] Fix race condition in RFCOMM session and dcl scheduler.

This fixes random RFCOMM freezes reported by some people.

include/net/bluetooth/rfcomm.h

@@ -220,9 +220,8 @@ static inline void rfcomm_schedule(uint event)
 {
 	if (!rfcomm_thread)
 		return;
-
 	//set_bit(event, &rfcomm_event);
-	if (!test_and_set_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event))
+	set_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event);
 	wake_up_process(rfcomm_thread);
 }
 

net/bluetooth/rfcomm/core.c

@@ -1485,7 +1485,7 @@ static inline int rfcomm_process_tx(struct rfcomm_dlc *d)
 	} else {
 		/* CFC disabled.
 		 * Give ourselves some credits */
-		d->tx_credits = RFCOMM_MAX_CREDITS;
+		d->tx_credits = 5;
 	}
 
 	if (test_bit(RFCOMM_TX_THROTTLED, &d->flags))
@@ -1651,7 +1651,7 @@ static void rfcomm_worker(void)
 	BT_DBG("");
 
 	while (!atomic_read(&terminate)) {
-		if (!test_and_clear_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event)) {
+		if (!test_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event)) {
 			/* No pending events. Let's sleep.
 			 * Incomming connections and data will wake us up. */
 			set_current_state(TASK_INTERRUPTIBLE);
@@ -1659,6 +1659,7 @@ static void rfcomm_worker(void)
 		}
 
 		/* Process stuff */
+		clear_bit(RFCOMM_SCHED_WAKEUP, &rfcomm_event);
 		rfcomm_process_sessions();
 	}
 	set_current_state(TASK_RUNNING);