ipi_from_irq      623 drivers/xen/events/events_base.c 			per_cpu(ipi_to_irq, cpu)[ipi_from_irq(irq)] = -1;
ipi_from_irq     1484 drivers/xen/events/events_base.c 		BUG_ON(ipi_from_irq(irq) != ipi);