wrapper/irqdesc.c

   1 /*
   2  * Copyright (C) 2011 Mathieu Desnoyers (mathieu.desnoyers@efficios.com)
   3  *
   4  * wrapper around irq_to_desc. Using KALLSYMS to get its address when
   5  * available, else we need to have a kernel that exports this function to GPL
   6  * modules.
   7  *
   8  * Dual LGPL v2.1/GPL v2 license.
   9  */
  10
  11 #ifdef CONFIG_KALLSYMS
  12
  13 #include <linux/kallsyms.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/irqnr.h>
  16 #include "kallsyms.h"
  17 #include "irqdesc.h"
  18
  19 static
  20 struct irq_desc *(*irq_to_desc_sym)(unsigned int irq);
  21
  22 struct irq_desc *wrapper_irq_to_desc(unsigned int irq)
  23 {
  24         if (!irq_to_desc_sym)
  25                 irq_to_desc_sym = (void *) kallsyms_lookup_funcptr("irq_to_desc");
  26         if (irq_to_desc_sym) {
  27                 return irq_to_desc_sym(irq);
  28         } else {
  29                 printk(KERN_WARNING "LTTng: irq_to_desc symbol lookup failed.\n");
  30                 return NULL;
  31         }
  32 }
  33
  34 #else
  35
  36 #include <linux/interrupt.h>
  37 #include <linux/irqnr.h>
  38
  39 struct irq_desc *wrapper_irq_to_desc(unsigned int irq)
  40 {
  41         return irq_to_desc(irq);
  42 }
  43
  44 #endif