Re: [PATCH] iqrdomain: Improve formatting in debugfs.

[Grant Likely <grant.likely@secretlab.ca>]

On Mon,  9 Apr 2012 17:06:57 -0700, David Daney <ddaney.cavm@gmail.com> wrote:
> From: David Daney <david.daney@cavium.com>
> 
> The irq_domain_mapping file has some interesting output when chip_data
> contains leading zeros:
> 
> virq   hwirq    chip name        chip data           domain name
> .
> .
> .
>   103  0x00000  CIU2-W           0x 5e0000000000000  none
>   104  0x00000  CIU2-W           0x 5f0000000000000  none
>   105  0x00000  CIU2-M           0x          (null)  none
>   113  0x00000  CIU2-E           0x1080000000000000  none
> .
> .
> .
> 
> I think there should be no space in there between the "0x" and the
> rest.  Also the '(null)' entry doesn't make much sense at all with a
> "0x".

Yeah, it doesn't make much sense with the '0x', but I don't want to
supress the (null) output because it is really important to highlight
when a domain isn't assigned to an active irq.

Fixing the zero pad is trivial to fix though.  Just remove the
precision from the %p format.  Here's my counter-patch:

---

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 9310a8d..eb05e40 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -643,8 +643,8 @@ static int virq_debug_show(struct seq_file *m, void *private)
 	void *data;
 	int i;
 
-	seq_printf(m, "%-5s  %-7s  %-15s  %-18s  %s\n", "virq", "hwirq",
-		      "chip name", "chip data", "domain name");
+	seq_printf(m, "%-5s  %-7s  %-15s  %-*s  %s\n", "irq", "hwirq",
+		      "chip name", 2 * sizeof(void *) + 2, "chip data", "domain name");
 
 	for (i = 1; i < nr_irqs; i++) {
 		desc = irq_to_desc(i);
@@ -667,7 +667,7 @@ static int virq_debug_show(struct seq_file *m, void *private)
 			seq_printf(m, "%-15s  ", p);
 
 			data = irq_desc_get_chip_data(desc);
-			seq_printf(m, "0x%16p  ", data);
+			seq_printf(m, data ? "0x%p  " : "  %p  ", data);
 
 			if (desc->irq_data.domain && desc->irq_data.domain->of_node)
 				p = desc->irq_data.domain->of_node->full_name;