cfe767ca154501460f9f7e757c08d881611e9c95
[linux-2.6.git] / kernel / irq / migration.c
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_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, desc->pending_mask);
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