diff options
Diffstat (limited to 'kernel/irq/irqdesc.c')
| -rw-r--r-- | kernel/irq/irqdesc.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c new file mode 100644 index 000000000000..fbf8cfa00510 --- /dev/null +++ b/kernel/irq/irqdesc.c | |||
| @@ -0,0 +1,269 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar | ||
| 3 | * Copyright (C) 2005-2006, Thomas Gleixner, Russell King | ||
| 4 | * | ||
| 5 | * This file contains the interrupt descriptor management code | ||
| 6 | * | ||
| 7 | * Detailed information is available in Documentation/DocBook/genericirq | ||
| 8 | * | ||
| 9 | */ | ||
| 10 | #include <linux/irq.h> | ||
| 11 | #include <linux/slab.h> | ||
| 12 | #include <linux/module.h> | ||
| 13 | #include <linux/interrupt.h> | ||
| 14 | #include <linux/kernel_stat.h> | ||
| 15 | #include <linux/radix-tree.h> | ||
| 16 | |||
| 17 | #include "internals.h" | ||
| 18 | |||
| 19 | /* | ||
| 20 | * lockdep: we want to handle all irq_desc locks as a single lock-class: | ||
| 21 | */ | ||
| 22 | struct lock_class_key irq_desc_lock_class; | ||
| 23 | |||
| 24 | #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_HARDIRQS) | ||
| 25 | static void __init init_irq_default_affinity(void) | ||
| 26 | { | ||
| 27 | alloc_cpumask_var(&irq_default_affinity, GFP_NOWAIT); | ||
| 28 | cpumask_setall(irq_default_affinity); | ||
| 29 | } | ||
| 30 | #else | ||
| 31 | static void __init init_irq_default_affinity(void) | ||
| 32 | { | ||
| 33 | } | ||
| 34 | #endif | ||
| 35 | |||
| 36 | int nr_irqs = NR_IRQS; | ||
| 37 | EXPORT_SYMBOL_GPL(nr_irqs); | ||
| 38 | |||
| 39 | #ifdef CONFIG_SPARSE_IRQ | ||
| 40 | |||
| 41 | static struct irq_desc irq_desc_init = { | ||
| 42 | .status = IRQ_DISABLED, | ||
| 43 | .handle_irq = handle_bad_irq, | ||
| 44 | .depth = 1, | ||
| 45 | .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock), | ||
| 46 | }; | ||
| 47 | |||
| 48 | void __ref init_kstat_irqs(struct irq_desc *desc, int node, int nr) | ||
| 49 | { | ||
| 50 | void *ptr; | ||
| 51 | |||
| 52 | ptr = kzalloc_node(nr * sizeof(*desc->kstat_irqs), | ||
| 53 | GFP_ATOMIC, node); | ||
| 54 | |||
| 55 | /* | ||
| 56 | * don't overwite if can not get new one | ||
| 57 | * init_copy_kstat_irqs() could still use old one | ||
| 58 | */ | ||
| 59 | if (ptr) { | ||
| 60 | printk(KERN_DEBUG " alloc kstat_irqs on node %d\n", node); | ||
| 61 | desc->kstat_irqs = ptr; | ||
| 62 | } | ||
| 63 | } | ||
| 64 | |||
| 65 | static void init_one_irq_desc(int irq, struct irq_desc *desc, int node) | ||
| 66 | { | ||
| 67 | memcpy(desc, &irq_desc_init, sizeof(struct irq_desc)); | ||
| 68 | |||
| 69 | raw_spin_lock_init(&desc->lock); | ||
| 70 | desc->irq_data.irq = irq; | ||
| 71 | #ifdef CONFIG_SMP | ||
| 72 | desc->irq_data.node = node; | ||
| 73 | #endif | ||
| 74 | lockdep_set_class(&desc->lock, &irq_desc_lock_class); | ||
| 75 | init_kstat_irqs(desc, node, nr_cpu_ids); | ||
| 76 | if (!desc->kstat_irqs) { | ||
| 77 | printk(KERN_ERR "can not alloc kstat_irqs\n"); | ||
| 78 | BUG_ON(1); | ||
| 79 | } | ||
| 80 | if (!alloc_desc_masks(desc, node, false)) { | ||
| 81 | printk(KERN_ERR "can not alloc irq_desc cpumasks\n"); | ||
| 82 | BUG_ON(1); | ||
| 83 | } | ||
| 84 | init_desc_masks(desc); | ||
| 85 | arch_init_chip_data(desc, node); | ||
| 86 | } | ||
| 87 | |||
| 88 | /* | ||
| 89 | * Protect the sparse_irqs: | ||
| 90 | */ | ||
| 91 | DEFINE_RAW_SPINLOCK(sparse_irq_lock); | ||
| 92 | |||
| 93 | static RADIX_TREE(irq_desc_tree, GFP_ATOMIC); | ||
| 94 | |||
| 95 | static void set_irq_desc(unsigned int irq, struct irq_desc *desc) | ||
| 96 | { | ||
| 97 | radix_tree_insert(&irq_desc_tree, irq, desc); | ||
| 98 | } | ||
| 99 | |||
| 100 | struct irq_desc *irq_to_desc(unsigned int irq) | ||
| 101 | { | ||
| 102 | return radix_tree_lookup(&irq_desc_tree, irq); | ||
| 103 | } | ||
| 104 | |||
| 105 | void replace_irq_desc(unsigned int irq, struct irq_desc *desc) | ||
| 106 | { | ||
| 107 | void **ptr; | ||
| 108 | |||
| 109 | ptr = radix_tree_lookup_slot(&irq_desc_tree, irq); | ||
| 110 | if (ptr) | ||
| 111 | radix_tree_replace_slot(ptr, desc); | ||
| 112 | } | ||
| 113 | |||
| 114 | static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = { | ||
| 115 | [0 ... NR_IRQS_LEGACY-1] = { | ||
| 116 | .status = IRQ_DISABLED, | ||
| 117 | .handle_irq = handle_bad_irq, | ||
| 118 | .depth = 1, | ||
| 119 | .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc_init.lock), | ||
| 120 | } | ||
| 121 | }; | ||
| 122 | |||
| 123 | static unsigned int *kstat_irqs_legacy; | ||
| 124 | |||
| 125 | int __init early_irq_init(void) | ||
| 126 | { | ||
| 127 | struct irq_desc *desc; | ||
| 128 | int legacy_count; | ||
| 129 | int node; | ||
| 130 | int i; | ||
| 131 | |||
| 132 | init_irq_default_affinity(); | ||
| 133 | |||
| 134 | /* initialize nr_irqs based on nr_cpu_ids */ | ||
| 135 | arch_probe_nr_irqs(); | ||
| 136 | printk(KERN_INFO "NR_IRQS:%d nr_irqs:%d\n", NR_IRQS, nr_irqs); | ||
| 137 | |||
| 138 | desc = irq_desc_legacy; | ||
| 139 | legacy_count = ARRAY_SIZE(irq_desc_legacy); | ||
| 140 | node = first_online_node; | ||
| 141 | |||
| 142 | /* allocate based on nr_cpu_ids */ | ||
| 143 | kstat_irqs_legacy = kzalloc_node(NR_IRQS_LEGACY * nr_cpu_ids * | ||
| 144 | sizeof(int), GFP_NOWAIT, node); | ||
| 145 | |||
| 146 | irq_desc_init.irq_data.chip = &no_irq_chip; | ||
| 147 | |||
| 148 | for (i = 0; i < legacy_count; i++) { | ||
| 149 | desc[i].irq_data.irq = i; | ||
| 150 | desc[i].irq_data.chip = &no_irq_chip; | ||
| 151 | #ifdef CONFIG_SMP | ||
| 152 | desc[i].irq_data.node = node; | ||
| 153 | #endif | ||
| 154 | desc[i].kstat_irqs = kstat_irqs_legacy + i * nr_cpu_ids; | ||
| 155 | lockdep_set_class(&desc[i].lock, &irq_desc_lock_class); | ||
| 156 | alloc_desc_masks(&desc[i], node, true); | ||
| 157 | init_desc_masks(&desc[i]); | ||
| 158 | set_irq_desc(i, &desc[i]); | ||
| 159 | } | ||
| 160 | |||
| 161 | return arch_early_irq_init(); | ||
| 162 | } | ||
| 163 | |||
| 164 | struct irq_desc * __ref irq_to_desc_alloc_node(unsigned int irq, int node) | ||
| 165 | { | ||
| 166 | struct irq_desc *desc; | ||
| 167 | unsigned long flags; | ||
| 168 | |||
| 169 | if (irq >= nr_irqs) { | ||
| 170 | WARN(1, "irq (%d) >= nr_irqs (%d) in irq_to_desc_alloc\n", | ||
| 171 | irq, nr_irqs); | ||
| 172 | return NULL; | ||
| 173 | } | ||
| 174 | |||
| 175 | desc = irq_to_desc(irq); | ||
| 176 | if (desc) | ||
| 177 | return desc; | ||
| 178 | |||
| 179 | raw_spin_lock_irqsave(&sparse_irq_lock, flags); | ||
| 180 | |||
| 181 | /* We have to check it to avoid races with another CPU */ | ||
| 182 | desc = irq_to_desc(irq); | ||
| 183 | if (desc) | ||
| 184 | goto out_unlock; | ||
| 185 | |||
| 186 | desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node); | ||
| 187 | |||
| 188 | printk(KERN_DEBUG " alloc irq_desc for %d on node %d\n", irq, node); | ||
| 189 | if (!desc) { | ||
| 190 | printk(KERN_ERR "can not alloc irq_desc\n"); | ||
| 191 | BUG_ON(1); | ||
| 192 | } | ||
| 193 | init_one_irq_desc(irq, desc, node); | ||
| 194 | |||
| 195 | set_irq_desc(irq, desc); | ||
| 196 | |||
| 197 | out_unlock: | ||
| 198 | raw_spin_unlock_irqrestore(&sparse_irq_lock, flags); | ||
| 199 | |||
| 200 | return desc; | ||
| 201 | } | ||
| 202 | |||
| 203 | #else /* !CONFIG_SPARSE_IRQ */ | ||
| 204 | |||
| 205 | struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = { | ||
| 206 | [0 ... NR_IRQS-1] = { | ||
| 207 | .status = IRQ_DISABLED, | ||
| 208 | .handle_irq = handle_bad_irq, | ||
| 209 | .depth = 1, | ||
| 210 | .lock = __RAW_SPIN_LOCK_UNLOCKED(irq_desc->lock), | ||
| 211 | } | ||
| 212 | }; | ||
| 213 | |||
| 214 | static unsigned int kstat_irqs_all[NR_IRQS][NR_CPUS]; | ||
| 215 | int __init early_irq_init(void) | ||
| 216 | { | ||
| 217 | struct irq_desc *desc; | ||
| 218 | int count; | ||
| 219 | int i; | ||
| 220 | |||
| 221 | init_irq_default_affinity(); | ||
| 222 | |||
| 223 | printk(KERN_INFO "NR_IRQS:%d\n", NR_IRQS); | ||
| 224 | |||
| 225 | desc = irq_desc; | ||
| 226 | count = ARRAY_SIZE(irq_desc); | ||
| 227 | |||
| 228 | for (i = 0; i < count; i++) { | ||
| 229 | desc[i].irq_data.irq = i; | ||
| 230 | desc[i].irq_data.chip = &no_irq_chip; | ||
| 231 | alloc_desc_masks(&desc[i], 0, true); | ||
| 232 | init_desc_masks(&desc[i]); | ||
| 233 | desc[i].kstat_irqs = kstat_irqs_all[i]; | ||
| 234 | } | ||
| 235 | return arch_early_irq_init(); | ||
| 236 | } | ||
| 237 | |||
| 238 | struct irq_desc *irq_to_desc(unsigned int irq) | ||
| 239 | { | ||
| 240 | return (irq < NR_IRQS) ? irq_desc + irq : NULL; | ||
| 241 | } | ||
| 242 | |||
| 243 | struct irq_desc *irq_to_desc_alloc_node(unsigned int irq, int node) | ||
| 244 | { | ||
| 245 | return irq_to_desc(irq); | ||
| 246 | } | ||
| 247 | #endif /* !CONFIG_SPARSE_IRQ */ | ||
| 248 | |||
| 249 | void clear_kstat_irqs(struct irq_desc *desc) | ||
| 250 | { | ||
| 251 | memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs))); | ||
| 252 | } | ||
| 253 | |||
| 254 | void early_init_irq_lock_class(void) | ||
| 255 | { | ||
| 256 | struct irq_desc *desc; | ||
| 257 | int i; | ||
| 258 | |||
| 259 | for_each_irq_desc(i, desc) { | ||
| 260 | lockdep_set_class(&desc->lock, &irq_desc_lock_class); | ||
| 261 | } | ||
| 262 | } | ||
| 263 | |||
| 264 | unsigned int kstat_irqs_cpu(unsigned int irq, int cpu) | ||
| 265 | { | ||
| 266 | struct irq_desc *desc = irq_to_desc(irq); | ||
| 267 | return desc ? desc->kstat_irqs[cpu] : 0; | ||
| 268 | } | ||
| 269 | EXPORT_SYMBOL(kstat_irqs_cpu); | ||
