cpumask: update irq_desc to use cpumask_var_t
[linux-2.6.git] / kernel / irq / numa_migrate.c
1 /*
2  * NUMA irq-desc migration code
3  *
4  * Migrate IRQ data structures (irq_desc, chip_data, etc.) over to
5  * the new "home node" of the IRQ.
6  */
7
8 #include <linux/irq.h>
9 #include <linux/module.h>
10 #include <linux/random.h>
11 #include <linux/interrupt.h>
12 #include <linux/kernel_stat.h>
13
14 #include "internals.h"
15
16 static void init_copy_kstat_irqs(struct irq_desc *old_desc,
17                                  struct irq_desc *desc,
18                                  int cpu, int nr)
19 {
20         unsigned long bytes;
21
22         init_kstat_irqs(desc, cpu, nr);
23
24         if (desc->kstat_irqs != old_desc->kstat_irqs) {
25                 /* Compute how many bytes we need per irq and allocate them */
26                 bytes = nr * sizeof(unsigned int);
27
28                 memcpy(desc->kstat_irqs, old_desc->kstat_irqs, bytes);
29         }
30 }
31
32 static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
33 {
34         if (old_desc->kstat_irqs == desc->kstat_irqs)
35                 return;
36
37         kfree(old_desc->kstat_irqs);
38         old_desc->kstat_irqs = NULL;
39 }
40
41 static void init_copy_one_irq_desc(int irq, struct irq_desc *old_desc,
42                  struct irq_desc *desc, int cpu)
43 {
44         memcpy(desc, old_desc, sizeof(struct irq_desc));
45         spin_lock_init(&desc->lock);
46         desc->cpu = cpu;
47         lockdep_set_class(&desc->lock, &irq_desc_lock_class);
48         init_copy_kstat_irqs(old_desc, desc, cpu, nr_cpu_ids);
49         init_copy_desc_masks(old_desc, desc);
50         arch_init_copy_chip_data(old_desc, desc, cpu);
51 }
52
53 static void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc)
54 {
55         free_kstat_irqs(old_desc, desc);
56         arch_free_chip_data(old_desc, desc);
57 }
58
59 static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
60                                                 int cpu)
61 {
62         struct irq_desc *desc;
63         unsigned int irq;
64         unsigned long flags;
65         int node;
66
67         irq = old_desc->irq;
68
69         spin_lock_irqsave(&sparse_irq_lock, flags);
70
71         /* We have to check it to avoid races with another CPU */
72         desc = irq_desc_ptrs[irq];
73
74         if (desc && old_desc != desc)
75                         goto out_unlock;
76
77         node = cpu_to_node(cpu);
78         desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
79         if (!desc) {
80                 printk(KERN_ERR "irq %d: can not get new irq_desc "
81                                 "for migration.\n", irq);
82                 /* still use old one */
83                 desc = old_desc;
84                 goto out_unlock;
85         }
86         if (!init_alloc_desc_masks(desc, node, false)) {
87                 printk(KERN_ERR "irq %d: can not get new irq_desc cpumask "
88                                 "for migration.\n", irq);
89                 /* still use old one */
90                 kfree(desc);
91                 desc = old_desc;
92                 goto out_unlock;
93         }
94         init_copy_one_irq_desc(irq, old_desc, desc, cpu);
95
96         irq_desc_ptrs[irq] = desc;
97
98         /* free the old one */
99         free_one_irq_desc(old_desc, desc);
100         kfree(old_desc);
101
102 out_unlock:
103         spin_unlock_irqrestore(&sparse_irq_lock, flags);
104
105         return desc;
106 }
107
108 struct irq_desc *move_irq_desc(struct irq_desc *desc, int cpu)
109 {
110         int old_cpu;
111         int node, old_node;
112
113         /* those all static, do move them */
114         if (desc->irq < NR_IRQS_LEGACY)
115                 return desc;
116
117         old_cpu = desc->cpu;
118         if (old_cpu != cpu) {
119                 node = cpu_to_node(cpu);
120                 old_node = cpu_to_node(old_cpu);
121                 if (old_node != node)
122                         desc = __real_move_irq_desc(desc, cpu);
123                 else
124                         desc->cpu = cpu;
125         }
126
127         return desc;
128 }
129