const char              *name;
 } ____cacheline_internodealigned_in_smp;
 
-extern struct irq_desc *irq_to_desc(unsigned int irq);
-extern struct irq_desc *irq_to_desc_alloc(unsigned int irq);
 
 #ifndef CONFIG_HAVE_SPARSE_IRQ
 
 extern struct irq_desc *irq_desc;
 #endif
 
+static inline struct irq_desc *irq_to_desc(unsigned int irq)
+{
+       return (irq < nr_irqs) ? irq_desc + irq : NULL;
+}
+
+static inline struct irq_desc *irq_to_desc_alloc(unsigned int irq)
+{
+       return irq_to_desc(irq);
+}
+
 #else
 
+extern struct irq_desc *irq_to_desc(unsigned int irq);
+extern struct irq_desc *irq_to_desc_alloc(unsigned int irq);
+
 extern struct irq_desc *sparse_irqs;
 #define for_each_irq_desc(irqX, desc)          \
        for (desc = sparse_irqs, irqX = desc->irq; desc; desc = desc->next, irqX = desc ? desc->irq : -1U)
 
 
 #endif
 
-#ifndef CONFIG_HAVE_SPARSE_IRQ
-struct irq_desc *irq_to_desc(unsigned int irq)
-{
-       if (irq < nr_irqs)
-               return &irq_desc[irq];
-
-       return NULL;
-}
-struct irq_desc *irq_to_desc_alloc(unsigned int irq)
-{
-       return irq_to_desc(irq);
-}
-#endif
-
 /*
  * What should we do if we get a hw irq event on an illegal vector?
  * Each architecture has to answer this themself.