xref: /openbmc/linux/kernel/irq/migration.c (revision b6dcefde)
1 
2 #include <linux/irq.h>
3 #include <linux/interrupt.h>
4 
5 #include "internals.h"
6 
7 void move_masked_irq(int irq)
8 {
9 	struct irq_desc *desc = irq_to_desc(irq);
10 
11 	if (likely(!(desc->status & IRQ_MOVE_PENDING)))
12 		return;
13 
14 	/*
15 	 * Paranoia: cpu-local interrupts shouldn't be calling in here anyway.
16 	 */
17 	if (CHECK_IRQ_PER_CPU(desc->status)) {
18 		WARN_ON(1);
19 		return;
20 	}
21 
22 	desc->status &= ~IRQ_MOVE_PENDING;
23 
24 	if (unlikely(cpumask_empty(desc->pending_mask)))
25 		return;
26 
27 	if (!desc->chip->set_affinity)
28 		return;
29 
30 	assert_raw_spin_locked(&desc->lock);
31 
32 	/*
33 	 * If there was a valid mask to work with, please
34 	 * do the disable, re-program, enable sequence.
35 	 * This is *not* particularly important for level triggered
36 	 * but in a edge trigger case, we might be setting rte
37 	 * when an active trigger is comming in. This could
38 	 * cause some ioapics to mal-function.
39 	 * Being paranoid i guess!
40 	 *
41 	 * For correct operation this depends on the caller
42 	 * masking the irqs.
43 	 */
44 	if (likely(cpumask_any_and(desc->pending_mask, cpu_online_mask)
45 		   < nr_cpu_ids))
46 		if (!desc->chip->set_affinity(irq, desc->pending_mask)) {
47 			cpumask_copy(desc->affinity, desc->pending_mask);
48 			irq_set_thread_affinity(desc);
49 		}
50 
51 	cpumask_clear(desc->pending_mask);
52 }
53 
54 void move_native_irq(int irq)
55 {
56 	struct irq_desc *desc = irq_to_desc(irq);
57 
58 	if (likely(!(desc->status & IRQ_MOVE_PENDING)))
59 		return;
60 
61 	if (unlikely(desc->status & IRQ_DISABLED))
62 		return;
63 
64 	desc->chip->mask(irq);
65 	move_masked_irq(irq);
66 	desc->chip->unmask(irq);
67 }
68 
69