xref: /openbmc/linux/kernel/irq/migration.c (revision 020c5260)
1 
2 #include <linux/irq.h>
3 #include <linux/interrupt.h>
4 
5 #include "internals.h"
6 
7 void irq_move_masked_irq(struct irq_data *idata)
8 {
9 	struct irq_desc *desc = irq_data_to_desc(idata);
10 	struct irq_chip *chip = desc->irq_data.chip;
11 
12 	if (likely(!irqd_is_setaffinity_pending(&desc->irq_data)))
13 		return;
14 
15 	irqd_clr_move_pending(&desc->irq_data);
16 
17 	/*
18 	 * Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
19 	 */
20 	if (irqd_is_per_cpu(&desc->irq_data)) {
21 		WARN_ON(1);
22 		return;
23 	}
24 
25 	if (unlikely(cpumask_empty(desc->pending_mask)))
26 		return;
27 
28 	if (!chip->irq_set_affinity)
29 		return;
30 
31 	assert_raw_spin_locked(&desc->lock);
32 
33 	/*
34 	 * If there was a valid mask to work with, please
35 	 * do the disable, re-program, enable sequence.
36 	 * This is *not* particularly important for level triggered
37 	 * but in a edge trigger case, we might be setting rte
38 	 * when an active trigger is coming in. This could
39 	 * cause some ioapics to mal-function.
40 	 * Being paranoid i guess!
41 	 *
42 	 * For correct operation this depends on the caller
43 	 * masking the irqs.
44 	 */
45 	if (cpumask_any_and(desc->pending_mask, cpu_online_mask) < nr_cpu_ids)
46 		irq_do_set_affinity(&desc->irq_data, desc->pending_mask, false);
47 
48 	cpumask_clear(desc->pending_mask);
49 }
50 
51 void irq_move_irq(struct irq_data *idata)
52 {
53 	bool masked;
54 
55 	/*
56 	 * Get top level irq_data when CONFIG_IRQ_DOMAIN_HIERARCHY is enabled,
57 	 * and it should be optimized away when CONFIG_IRQ_DOMAIN_HIERARCHY is
58 	 * disabled. So we avoid an "#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY" here.
59 	 */
60 	idata = irq_desc_get_irq_data(irq_data_to_desc(idata));
61 
62 	if (likely(!irqd_is_setaffinity_pending(idata)))
63 		return;
64 
65 	if (unlikely(irqd_irq_disabled(idata)))
66 		return;
67 
68 	/*
69 	 * Be careful vs. already masked interrupts. If this is a
70 	 * threaded interrupt with ONESHOT set, we can end up with an
71 	 * interrupt storm.
72 	 */
73 	masked = irqd_irq_masked(idata);
74 	if (!masked)
75 		idata->chip->irq_mask(idata);
76 	irq_move_masked_irq(idata);
77 	if (!masked)
78 		idata->chip->irq_unmask(idata);
79 }
80