genirq: Cleanup forced threading bits when handler thread terminates

When a handler thread terminates then the forced_thread_active bit
might be still set. Cleanup and unmask the interrupt if this is the
last thread which blocked the unmask.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

kernel/irq/manage.c

@@ -537,6 +537,14 @@ static void preempt_hardirq_setup(struct irqaction *new)
 	new->thread_fn = new->handler;
 	new->handler = preempt_hardirq_handler;
 }
+
+static inline void
+preempt_hardirq_cleanup(struct irq_desc *desc, struct irqaction *action)
+{
+	clear_bit(IRQTF_RUNTHREAD, &action->thread_flags);
+	preempt_hardirq_thread_done(desc, action);
+}
+
 #else
 static inline void preempt_hardirq_setup(struct irqaction *new) { }
 static inline int
@@ -544,6 +552,8 @@ preempt_hardirq_thread_done(struct irq_desc *d, struct irqaction *a)
 {
 	return 0;
 }
+static inline void
+preempt_hardirq_cleanup(struct irq_desc *d, struct irqaction *a) { }
 #endif
 
 static int
@@ -639,6 +649,8 @@ static int irq_thread(void *data)
 			wake_up(&desc->wait_for_threads);
 	}
 
+	preempt_hardirq_cleanup(desc, action);
+
 	/*
 	 * Clear irqaction. Otherwise exit_irq_thread() would make
 	 * fuzz about an active irq thread going into nirvana.