x86: use NR_IRQS_LEGACY
[linux-2.6.git] / kernel / irq / handle.c
index 9fe86b3..8aa0954 100644 (file)
 #include <linux/random.h>
 #include <linux/interrupt.h>
 #include <linux/kernel_stat.h>
+#include <linux/rculist.h>
+#include <linux/hash.h>
 
 #include "internals.h"
 
+/*
+ * lockdep: we want to handle all irq_desc locks as a single lock-class:
+ */
+static struct lock_class_key irq_desc_lock_class;
+
 /**
  * handle_bad_irq - handle spurious and unhandled irqs
  * @irq:       the interrupt number
@@ -49,6 +56,155 @@ void handle_bad_irq(unsigned int irq, struct irq_desc *desc)
 int nr_irqs = NR_IRQS;
 EXPORT_SYMBOL_GPL(nr_irqs);
 
+void __init __attribute__((weak)) arch_early_irq_init(void)
+{
+}
+
+#ifdef CONFIG_SPARSE_IRQ
+static struct irq_desc irq_desc_init = {
+       .irq        = -1,
+       .status     = IRQ_DISABLED,
+       .chip       = &no_irq_chip,
+       .handle_irq = handle_bad_irq,
+       .depth      = 1,
+       .lock       = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
+#ifdef CONFIG_SMP
+       .affinity   = CPU_MASK_ALL
+#endif
+};
+
+static void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
+{
+       unsigned long bytes;
+       char *ptr;
+       int node;
+
+       /* Compute how many bytes we need per irq and allocate them */
+       bytes = nr * sizeof(unsigned int);
+
+       node = cpu_to_node(cpu);
+       ptr = kzalloc_node(bytes, GFP_ATOMIC, node);
+       printk(KERN_DEBUG "  alloc kstat_irqs on cpu %d node %d\n", cpu, node);
+
+       if (ptr)
+               desc->kstat_irqs = (unsigned int *)ptr;
+}
+
+void __attribute__((weak)) arch_init_chip_data(struct irq_desc *desc, int cpu)
+{
+}
+
+static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
+{
+       memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
+       desc->irq = irq;
+#ifdef CONFIG_SMP
+       desc->cpu = cpu;
+#endif
+       lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+       init_kstat_irqs(desc, cpu, nr_cpu_ids);
+       if (!desc->kstat_irqs) {
+               printk(KERN_ERR "can not alloc kstat_irqs\n");
+               BUG_ON(1);
+       }
+       arch_init_chip_data(desc, cpu);
+}
+
+/*
+ * Protect the sparse_irqs:
+ */
+static DEFINE_SPINLOCK(sparse_irq_lock);
+
+struct irq_desc *irq_desc_ptrs[NR_IRQS] __read_mostly;
+
+static struct irq_desc irq_desc_legacy[NR_IRQS_LEGACY] __cacheline_aligned_in_smp = {
+       [0 ... NR_IRQS_LEGACY-1] = {
+               .irq        = -1,
+               .status     = IRQ_DISABLED,
+               .chip       = &no_irq_chip,
+               .handle_irq = handle_bad_irq,
+               .depth      = 1,
+               .lock       = __SPIN_LOCK_UNLOCKED(irq_desc_init.lock),
+#ifdef CONFIG_SMP
+               .affinity   = CPU_MASK_ALL
+#endif
+       }
+};
+
+/* FIXME: use bootmem alloc ...*/
+static unsigned int kstat_irqs_legacy[NR_IRQS_LEGACY][NR_CPUS];
+
+void __init early_irq_init(void)
+{
+       struct irq_desc *desc;
+       int legacy_count;
+       int i;
+
+       desc = irq_desc_legacy;
+       legacy_count = ARRAY_SIZE(irq_desc_legacy);
+
+       for (i = 0; i < legacy_count; i++) {
+               desc[i].irq = i;
+               desc[i].kstat_irqs = kstat_irqs_legacy[i];
+
+               irq_desc_ptrs[i] = desc + i;
+       }
+
+       for (i = legacy_count; i < NR_IRQS; i++)
+               irq_desc_ptrs[i] = NULL;
+
+       arch_early_irq_init();
+}
+
+struct irq_desc *irq_to_desc(unsigned int irq)
+{
+       return (irq < NR_IRQS) ? irq_desc_ptrs[irq] : NULL;
+}
+
+struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
+{
+       struct irq_desc *desc;
+       unsigned long flags;
+       int node;
+
+       if (irq >= NR_IRQS) {
+               printk(KERN_WARNING "irq >= NR_IRQS in irq_to_desc_alloc: %d %d\n",
+                               irq, NR_IRQS);
+               WARN_ON(1);
+               return NULL;
+       }
+
+       desc = irq_desc_ptrs[irq];
+       if (desc)
+               return desc;
+
+       spin_lock_irqsave(&sparse_irq_lock, flags);
+
+       /* We have to check it to avoid races with another CPU */
+       desc = irq_desc_ptrs[irq];
+       if (desc)
+               goto out_unlock;
+
+       node = cpu_to_node(cpu);
+       desc = kzalloc_node(sizeof(*desc), GFP_ATOMIC, node);
+       printk(KERN_DEBUG "  alloc irq_desc for %d on cpu %d node %d\n",
+                irq, cpu, node);
+       if (!desc) {
+               printk(KERN_ERR "can not alloc irq_desc\n");
+               BUG_ON(1);
+       }
+       init_one_irq_desc(irq, desc, cpu);
+
+       irq_desc_ptrs[irq] = desc;
+
+out_unlock:
+       spin_unlock_irqrestore(&sparse_irq_lock, flags);
+
+       return desc;
+}
+
+#else
+
 struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
        [0 ... NR_IRQS-1] = {
                .status = IRQ_DISABLED,
@@ -62,15 +218,16 @@ struct irq_desc irq_desc[NR_IRQS] __cacheline_aligned_in_smp = {
        }
 };
 
+#endif
+
 /*
  * What should we do if we get a hw irq event on an illegal vector?
  * Each architecture has to answer this themself.
  */
 static void ack_bad(unsigned int irq)
 {
-       struct irq_desc *desc;
+       struct irq_desc *desc = irq_to_desc(irq);
 
-       desc = irq_to_desc(irq);
        print_irq_desc(irq, desc);
        ack_bad_irq(irq);
 }
@@ -262,16 +419,28 @@ out:
 
 
 #ifdef CONFIG_TRACE_IRQFLAGS
-/*
- * lockdep: we want to handle all irq_desc locks as a single lock-class:
- */
-static struct lock_class_key irq_desc_lock_class;
-
 void early_init_irq_lock_class(void)
 {
+#ifndef CONFIG_SPARSE_IRQ
+       struct irq_desc *desc;
        int i;
 
-       for (i = 0; i < nr_irqs; i++)
-               lockdep_set_class(&irq_desc[i].lock, &irq_desc_lock_class);
+       for_each_irq_desc(i, desc) {
+               if (!desc)
+                       continue;
+
+               lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+       }
+#endif
+}
+#endif
+
+#ifdef CONFIG_SPARSE_IRQ
+unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
+{
+       struct irq_desc *desc = irq_to_desc(irq);
+       return desc->kstat_irqs[cpu];
 }
 #endif
+EXPORT_SYMBOL(kstat_irqs_cpu);
+