x86: cleanup show_interrupts

The sparseirq patches introduced some more ugliness in show_interrupts().
Clean it up all together and make the code easier to read by splitting out
the "tail" function  which prints the special interrupts.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 77 insertions, 76 deletions

diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index 21f53b911113..4f374294f292 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -68,22 +68,65 @@ static inline void stack_overflow_check(struct pt_regs *regs)
  * Generic, controller-independent functions:
  */
 
+static int show_other_interrupts(struct seq_file *p)
+{
+        int j;
+
+        seq_printf(p, "NMI: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
+        seq_printf(p, "  Non-maskable interrupts\n");
+        seq_printf(p, "LOC: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
+        seq_printf(p, "  Local timer interrupts\n");
+#ifdef CONFIG_SMP
+        seq_printf(p, "RES: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->irq_resched_count);
+        seq_printf(p, "  Rescheduling interrupts\n");
+        seq_printf(p, "CAL: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->irq_call_count);
+        seq_printf(p, "  Function call interrupts\n");
+        seq_printf(p, "TLB: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->irq_tlb_count);
+        seq_printf(p, "  TLB shootdowns\n");
+#endif
+#ifdef CONFIG_X86_MCE
+        seq_printf(p, "TRM: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->irq_thermal_count);
+        seq_printf(p, "  Thermal event interrupts\n");
+        seq_printf(p, "THR: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->irq_threshold_count);
+        seq_printf(p, "  Threshold APIC interrupts\n");
+#endif
+        seq_printf(p, "SPU: ");
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", cpu_pda(j)->irq_spurious_count);
+        seq_printf(p, "  Spurious interrupts\n");
+        seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
+
+        return 0;
+}
+
 int show_interrupts(struct seq_file *p, void *v)
 {
-        int i, j;
-        struct irqaction * action;
-        unsigned long flags;
-        unsigned int entries;
-        struct irq_desc *desc = NULL;
-        int tail = 0;
-
-        entries = nr_irqs - 1;
-        i = *(loff_t *) v;
+        unsigned long flags, any_count = 0;
+        int i = *(loff_t *) v, j;
+        struct irqaction *action;
+        struct irq_desc *desc;
+
+        if (i > nr_irqs)
+                return 0;
+
         if (i == nr_irqs)
-                tail = 1;
-        else
-                desc = irq_to_desc(i);
+                return show_other_interrupts(p);
 
+        /* print header */
         if (i == 0) {
                 seq_printf(p, "           ");
                 for_each_online_cpu(j)
@@ -91,79 +134,37 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_putc(p, '\n');
         }
 
-        if (i <= entries) {
-                unsigned any_count = 0;
-
-                spin_lock_irqsave(&desc->lock, flags);
+        desc = irq_to_desc(i);
+        spin_lock_irqsave(&desc->lock, flags);
 #ifndef CONFIG_SMP
-                any_count = kstat_irqs(i);
+        any_count = kstat_irqs(i);
 #else
-                for_each_online_cpu(j)
-                        any_count |= kstat_irqs_cpu(i, j);
+        for_each_online_cpu(j)
+                any_count |= kstat_irqs_cpu(i, j);
 #endif
-                action = desc->action;
-                if (!action && !any_count)
-                        goto skip;
-                seq_printf(p, "%3d: ", i);
+        action = desc->action;
+        if (!action && !any_count)
+                goto out;
+
+        seq_printf(p, "%3d: ", i);
 #ifndef CONFIG_SMP
-                seq_printf(p, "%10u ", kstat_irqs(i));
+        seq_printf(p, "%10u ", kstat_irqs(i));
 #else
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
+        for_each_online_cpu(j)
+                seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
 #endif
-                seq_printf(p, " %8s", desc->chip->name);
-                seq_printf(p, "-%-8s", desc->name);
+        seq_printf(p, " %8s", desc->chip->name);
+        seq_printf(p, "-%-8s", desc->name);
 
-                if (action) {
-                        seq_printf(p, "  %s", action->name);
-                        while ((action = action->next) != NULL)
-                                seq_printf(p, ", %s", action->name);
-                }
-                seq_putc(p, '\n');
-skip:
-                spin_unlock_irqrestore(&desc->lock, flags);
-        }
-
-        if (tail) {
-                seq_printf(p, "NMI: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
-                seq_printf(p, "  Non-maskable interrupts\n");
-                seq_printf(p, "LOC: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
-                seq_printf(p, "  Local timer interrupts\n");
-#ifdef CONFIG_SMP
-                seq_printf(p, "RES: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->irq_resched_count);
-                seq_printf(p, "  Rescheduling interrupts\n");
-                seq_printf(p, "CAL: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->irq_call_count);
-                seq_printf(p, "  Function call interrupts\n");
-                seq_printf(p, "TLB: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->irq_tlb_count);
-                seq_printf(p, "  TLB shootdowns\n");
-#endif
-#ifdef CONFIG_X86_MCE
-                seq_printf(p, "TRM: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->irq_thermal_count);
-                seq_printf(p, "  Thermal event interrupts\n");
-                seq_printf(p, "THR: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->irq_threshold_count);
-                seq_printf(p, "  Threshold APIC interrupts\n");
-#endif
-                seq_printf(p, "SPU: ");
-                for_each_online_cpu(j)
-                        seq_printf(p, "%10u ", cpu_pda(j)->irq_spurious_count);
-                seq_printf(p, "  Spurious interrupts\n");
-                seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
+        if (action) {
+                seq_printf(p, "  %s", action->name);
+                while ((action = action->next) != NULL)
+                        seq_printf(p, ", %s", action->name);
         }
 
+        seq_putc(p, '\n');
+out:
+        spin_unlock_irqrestore(&desc->lock, flags);
         return 0;
 }