Initial commit

kernel/irq/migration.c

@@ -0,0 +1,75 @@
+
+#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);
+}
+