[S390] irq: have detailed statistics for interrupt types

Up to now /proc/interrupts only has statistics for external and i/o
interrupts but doesn't split up them any further.
This patch adds a line for every single interrupt source so that it
is possible to easier tell what the machine is/was doing.
Part of the output now looks like this;

           CPU0       CPU2       CPU4
EXT:       3898       4232       2305
I/O:        782        315        245
CLK:       1029       1964        727   [EXT] Clock Comparator
IPI:       2868       2267       1577   [EXT] Signal Processor
TMR:          0          0          0   [EXT] CPU Timer
TAL:          0          0          0   [EXT] Timing Alert
PFL:          0          0          0   [EXT] Pseudo Page Fault
[...]
NMI:          0          1          1   [NMI] Machine Checks

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 026a37a..9bd049b 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -1,7 +1,5 @@
 /*
- *  arch/s390/kernel/irq.c
- *
- *    Copyright IBM Corp. 2004,2007
+ *    Copyright IBM Corp. 2004,2010
  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
  *		 Thomas Spatzier (tspat@de.ibm.com)
  *
@@ -17,12 +15,31 @@
 #include <linux/proc_fs.h>
 #include <linux/profile.h>
 
+struct irq_class {
+	char *name;
+	char *desc;
+};
+
+static const struct irq_class intrclass_names[] = {
+	{.name = "EXT" },
+	{.name = "I/O" },
+	{.name = "CLK", .desc = "[EXT] Clock Comparator" },
+	{.name = "IPI", .desc = "[EXT] Signal Processor" },
+	{.name = "TMR", .desc = "[EXT] CPU Timer" },
+	{.name = "TAL", .desc = "[EXT] Timing Alert" },
+	{.name = "PFL", .desc = "[EXT] Pseudo Page Fault" },
+	{.name = "DSD", .desc = "[EXT] DASD Diag" },
+	{.name = "VRT", .desc = "[EXT] Virtio" },
+	{.name = "SCP", .desc = "[EXT] Service Call" },
+	{.name = "IUC", .desc = "[EXT] IUCV" },
+	{.name = "NMI", .desc = "[NMI] Machine Check" },
+};
+
 /*
  * show_interrupts is needed by /proc/interrupts.
  */
 int show_interrupts(struct seq_file *p, void *v)
 {
-	static const char *intrclass_names[] = { "EXT", "I/O", };
 	int i = *(loff_t *) v, j;
 
 	get_online_cpus();
@@ -34,15 +51,16 @@
 	}
 
 	if (i < NR_IRQS) {
-		seq_printf(p, "%s: ", intrclass_names[i]);
+		seq_printf(p, "%s: ", intrclass_names[i].name);
 #ifndef CONFIG_SMP
 		seq_printf(p, "%10u ", kstat_irqs(i));
 #else
 		for_each_online_cpu(j)
 			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 #endif
+		if (intrclass_names[i].desc)
+			seq_printf(p, "  %s", intrclass_names[i].desc);
                 seq_putc(p, '\n');
-
         }
 	put_online_cpus();
         return 0;