root/kernel/irq/migration.c

DEFINITIONS

1. set_pending_irq
2. move_masked_irq
3. move_native_irq

#include <linux/irq.h>

void set_pending_irq(unsigned int irq, cpumask_t mask)
{
        struct irq_desc *desc = irq_desc + irq;
        unsigned long flags;

        spin_lock_irqsave(&desc->lock, flags);
        desc->status |= IRQ_MOVE_PENDING;
        irq_desc[irq].pending_mask = mask;
        spin_unlock_irqrestore(&desc->lock, flags);
}

void move_masked_irq(int irq)
{
        struct irq_desc *desc = irq_desc + irq;
        cpumask_t tmp;

        if (likely(!(desc->status & IRQ_MOVE_PENDING)))
                return;

        /*
         * Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
         */
        if (CHECK_IRQ_PER_CPU(desc->status)) {
                WARN_ON(1);
                return;
        }

        desc->status &= ~IRQ_MOVE_PENDING;

        if (unlikely(cpus_empty(irq_desc[irq].pending_mask)))
                return;

        if (!desc->chip->set_affinity)
                return;

        assert_spin_locked(&desc->lock);

        cpus_and(tmp, irq_desc[irq].pending_mask, cpu_online_map);

        /*
         * If there was a valid mask to work with, please
         * do the disable, re-program, enable sequence.
         * This is *not* particularly important for level triggered
         * but in a edge trigger case, we might be setting rte
         * when an active trigger is comming in. This could
         * cause some ioapics to mal-function.
         * Being paranoid i guess!
         *
         * For correct operation this depends on the caller
         * masking the irqs.
         */
        if (likely(!cpus_empty(tmp))) {
                desc->chip->set_affinity(irq,tmp);
        }
        cpus_clear(irq_desc[irq].pending_mask);
}

void move_native_irq(int irq)
{
        struct irq_desc *desc = irq_desc + irq;

        if (likely(!(desc->status & IRQ_MOVE_PENDING)))
                return;

        if (unlikely(desc->status & IRQ_DISABLED))
                return;

        desc->chip->mask(irq);
        move_masked_irq(irq);
        desc->chip->unmask(irq);
}