irq: replace loop with nr_irqs with for_each_irq_desc
There are a handful of loops that go from 0 to nr_irqs and use
get_irq_desc() on them. These would allocate all the irq_desc
entries, regardless of the need for them.
Use the smarter for_each_irq_desc() iterator that will only iterate
over the present ones.
v2: make sure arch without GENERIC_HARDIRQS work too
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/irqinit_64.c b/arch/x86/kernel/irqinit_64.c
index 0744b49..cd9f42d 100644
--- a/arch/x86/kernel/irqinit_64.c
+++ b/arch/x86/kernel/irqinit_64.c
@@ -142,25 +142,18 @@
init_bsp_APIC();
init_8259A(0);
- for (i = 0; i < nr_irqs; i++) {
+ for (i = 0; i < 16; i++) {
struct irq_desc *desc = irq_to_desc(i);
desc->status = IRQ_DISABLED;
desc->action = NULL;
desc->depth = 1;
- if (i < 16) {
- /*
- * 16 old-style INTA-cycle interrupts:
- */
- set_irq_chip_and_handler_name(i, &i8259A_chip,
+ /*
+ * 16 old-style INTA-cycle interrupts:
+ */
+ set_irq_chip_and_handler_name(i, &i8259A_chip,
handle_level_irq, "XT");
- } else {
- /*
- * 'high' PCI IRQs filled in on demand
- */
- desc->chip = &no_irq_chip;
- }
}
}