genirq: Implement sane enumeration

Use the allocator bitmap to lookup active interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 0 deletions

diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c
index 6312a2c83971..2e7e94ef64da 100644
--- a/kernel/irq/irqdesc.c
+++ b/kernel/irq/irqdesc.c
@@ -463,6 +463,17 @@ err:
         return ret;
 }
 
+/**
+ * irq_get_next_irq - get next allocated irq number
+ * @offset:     where to start the search
+ *
+ * Returns next irq number after offset or nr_irqs if none is found.
+ */
+unsigned int irq_get_next_irq(unsigned int offset)
+{
+        return find_next_bit(allocated_irqs, nr_irqs, offset);
+}
+
 /* Statistics access */
 void clear_kstat_irqs(struct irq_desc *desc)
 {