[PATCH] genirq: for edge interrupt IRQS_ONESHOT support with irq thread

[Chuansheng Liu <chuansheng.liu@intel.com>]

In our system, there is one edge interrupt, and we want it to be
irq thread with IRQS_ONESHOT, and found in handle_edge_irq(),
even with IRQS_ONESHOT, the irq is still unmasked without care of
flag IRQS_ONESHOT.

It causes IRQS_ONESHOT can not work well for edge interrupt, but also
after the irq thread finished with flag IRQS_ONESHOT, the irq will be
possible to be unmasked again, it should be messing mask/unmask logic.

Signed-off-by: liu chuansheng <chuansheng.liu@intel.com>
---
 kernel/irq/chip.c |    8 +++++++-
 1 files changed, 7 insertions(+), 1 deletions(-)

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 57d86d0..f23f524 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -497,7 +497,13 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc)
 	kstat_incr_irqs_this_cpu(irq, desc);
 
 	/* Start handling the irq */
-	desc->irq_data.chip->irq_ack(&desc->irq_data);
+	if (desc->istate & IRQS_ONESHOT) {
+		mask_ack_irq(desc);
+		handle_irq_event(desc);
+		cond_unmask_irq(desc);
+		goto out_unlock;
+	} else
+		desc->irq_data.chip->irq_ack(&desc->irq_data);
 
 	do {
 		if (unlikely(!desc->action)) {
-- 
1.7.0.4