[PATCH] genirq: Allow fasteoi handler to retrigger disabled interrupts

Make the fasteoi handler mark disabled interrupts as pending if they
happen anyway. This allow implementation of a delayed disable scheme
with the fasteoi handler.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

kernel/irq/chip.c

@@ -261,10 +261,13 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc, struct pt_regs *regs)
 	 * keep it masked and get out of here
 	 */
 	action = desc->action;
-	if (unlikely(!action || (desc->status & IRQ_DISABLED)))
+	if (unlikely(!action || (desc->status & IRQ_DISABLED))) {
+		desc->status |= IRQ_PENDING;
 		goto out;
+	}
 
 	desc->status |= IRQ_INPROGRESS;
+	desc->status &= ~IRQ_PENDING;
 	spin_unlock(&desc->lock);
 
 	action_ret = handle_IRQ_event(irq, regs, action);