powerpc: Rework /proc/interrupts

On a large machine I noticed the columns of /proc/interrupts failed to line up
with the header after CPU9. At sufficiently large numbers of CPUs it becomes
impossible to line up the CPU number with the counts.

While fixing this I noticed x86 has a number of updates that we may as well
pull in. On PowerPC we currently omit an interrupt completely if there is no
active handler, whereas on x86 it is printed if there is a non zero count.

The x86 code also spaces the first column correctly based on nr_irqs.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index c6ac5583672a7b73f3733cc5f389688ad4985296..b9cbb457004869f84000bd80c72decf0a89e5910 100644 (file)
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -183,30 +183,46 @@ notrace void raw_local_irq_restore(unsigned long en)
 EXPORT_SYMBOL(raw_local_irq_restore);
 #endif /* CONFIG_PPC64 */
 
+static int show_other_interrupts(struct seq_file *p, int prec)
+{
+       int j;
+
+#if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT)
+       if (tau_initialized) {
+               seq_printf(p, "%*s: ", prec, "TAU");
+               for_each_online_cpu(j)
+                       seq_printf(p, "%10u ", tau_interrupts(j));
+               seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
+       }
+#endif /* CONFIG_PPC32 && CONFIG_TAU_INT */
+
+       seq_printf(p, "%*s: %10u\n", prec, "BAD", ppc_spurious_interrupts);
+
+       return 0;
+}
+
 int show_interrupts(struct seq_file *p, void *v)
 {
-       int i = *(loff_t *)v, j;
+       unsigned long flags, any_count = 0;
+       int i = *(loff_t *) v, j, prec;
        struct irqaction *action;
        struct irq_desc *desc;
-       unsigned long flags;
 
+       if (i > nr_irqs)
+               return 0;
+
+       for (prec = 3, j = 1000; prec < 10 && j <= nr_irqs; ++prec)
+               j *= 10;
+
+       if (i == nr_irqs)
+               return show_other_interrupts(p, prec);
+
+       /* print header */
        if (i == 0) {
-               seq_puts(p, "           ");
+               seq_printf(p, "%*s", prec + 8, "");
                for_each_online_cpu(j)
-                       seq_printf(p, "CPU%d       ", j);
+                       seq_printf(p, "CPU%-8d", j);
                seq_putc(p, '\n');
-       } else if (i == nr_irqs) {
-#if defined(CONFIG_PPC32) && defined(CONFIG_TAU_INT)
-               if (tau_initialized){
-                       seq_puts(p, "TAU: ");
-                       for_each_online_cpu(j)
-                               seq_printf(p, "%10u ", tau_interrupts(j));
-                       seq_puts(p, "  PowerPC             Thermal Assist (cpu temp)\n");
-               }
-#endif /* CONFIG_PPC32 && CONFIG_TAU_INT*/
-               seq_printf(p, "BAD: %10u\n", ppc_spurious_interrupts);
-
-               return 0;
        }
 
        desc = irq_to_desc(i);
@@ -214,34 +230,31 @@ int show_interrupts(struct seq_file *p, void *v)
                return 0;
 
        raw_spin_lock_irqsave(&desc->lock, flags);
-
+       for_each_online_cpu(j)
+               any_count |= kstat_irqs_cpu(i, j);
        action = desc->action;
-       if (!action || !action->handler)
-               goto skip;
+       if (!action && !any_count)
+               goto out;
 
-       seq_printf(p, "%3d: ", i);
-#ifdef CONFIG_SMP
+       seq_printf(p, "%*d: ", prec, i);
        for_each_online_cpu(j)
                seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
-#else
-       seq_printf(p, "%10u ", kstat_irqs(i));
-#endif /* CONFIG_SMP */
 
        if (desc->chip)
-               seq_printf(p, " %s ", desc->chip->name);
+               seq_printf(p, "  %-16s", desc->chip->name);
        else
-               seq_puts(p, "  None      ");
+               seq_printf(p, "  %-16s", "None");
+       seq_printf(p, " %-8s", (desc->status & IRQ_LEVEL) ? "Level" : "Edge");
 
-       seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
-       seq_printf(p, "    %s", action->name);
+       if (action) {
+               seq_printf(p, "     %s", action->name);
+               while ((action = action->next) != NULL)
+                       seq_printf(p, ", %s", action->name);
+       }
 
-       for (action = action->next; action; action = action->next)
-               seq_printf(p, ", %s", action->name);
        seq_putc(p, '\n');
-
-skip:
+out:
        raw_spin_unlock_irqrestore(&desc->lock, flags);
-
        return 0;
 }