The MIPS GIC driver has previously iterated over bits set in a bitmap
representing pending IRQs by calling find_first_bit, clearing that bit
then calling find_first_bit again until all bits are clear. If multiple
interrupts are pending then this is wasteful, as find_first_bit will
have to loop over the whole bitmap from the start. Use the
for_each_set_bit macro which performs exactly what we need here instead.
It will use find_next_bit and thus only scan over the relevant part of
the bitmap, and it makes the intent of the code clearer.
Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---
drivers/irqchip/irq-mips-gic.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
index d3ef0fc..e9e5022 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -371,18 +371,13 @@ static void gic_handle_shared_int(bool chained)
bitmap_and(pending, pending, intrmask, gic_shared_intrs);
bitmap_and(pending, pending, pcpu_mask, gic_shared_intrs);
- intr = find_first_bit(pending, gic_shared_intrs);
- while (intr != gic_shared_intrs) {
+ for_each_set_bit(intr, pending, gic_shared_intrs) {
virq = irq_linear_revmap(gic_irq_domain,
GIC_SHARED_TO_HWIRQ(intr));
if (chained)
generic_handle_irq(virq);
else
do_IRQ(virq);
-
- /* go to next pending bit */
- bitmap_clear(pending, intr, 1);
- intr = find_first_bit(pending, gic_shared_intrs);
}
}
--
2.9.3
