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 <[email protected]> --- 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
