Implement state dump

[lttng-modules.git] / wrapper / irqdesc.c

diff --git a/wrapper/irqdesc.c b/wrapper/irqdesc.c
new file mode 100644 (file)
index 0000000..a71981e
--- /dev/null
+++ b/wrapper/irqdesc.c
@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2011 Mathieu Desnoyers (mathieu.desnoyers@efficios.com)
+ *
+ * wrapper around irq_to_desc. Using KALLSYMS to get its address when
+ * available, else we need to have a kernel that exports this function to GPL
+ * modules.
+ *
+ * Dual LGPL v2.1/GPL v2 license.
+ */
+
+#ifdef CONFIG_KALLSYMS
+
+#include <linux/kallsyms.h>
+#include <linux/interrupt.h>
+#include <linux/irqnr.h>
+#include "kallsyms.h"
+#include "irqdesc.h"
+
+static
+struct irq_desc *(*irq_to_desc_sym)(unsigned int irq);
+
+struct irq_desc *wrapper_irq_to_desc(unsigned int irq)
+{
+       if (!irq_to_desc_sym)
+               irq_to_desc_sym = (void *) kallsyms_lookup_funcptr("irq_to_desc"); 
+       if (irq_to_desc_sym) {
+               return irq_to_desc_sym(irq);
+       } else {
+               printk(KERN_WARNING "LTTng: irq_to_desc symbol lookup failed.\n");
+               return NULL;
+       }
+}
+
+#else
+
+#include <linux/interrupt.h>
+#include <linux/irqnr.h>
+
+struct irq_desc *wrapper_irq_to_desc(unsigned int irq)
+{
+       return irq_to_desc(irq);
+}
+
+#endif