SOFTIRQ_SHIFT      32 include/linux/preempt_mask.h #define HARDIRQ_SHIFT	(SOFTIRQ_SHIFT + SOFTIRQ_BITS)
SOFTIRQ_SHIFT      38 include/linux/preempt_mask.h #define SOFTIRQ_MASK	(__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
SOFTIRQ_SHIFT      43 include/linux/preempt_mask.h #define SOFTIRQ_OFFSET	(1UL << SOFTIRQ_SHIFT)