Re: [PATCH for -tip 3/4] proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c

[KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>]

> On Thu, Dec 25, 2008 at 8:21 PM, KOSAKI Motohiro
> <kosaki.motohiro@jp.fujitsu.com> wrote:
> >> > Subject: [PATCH] proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c
> >> > Impact: cleanup
> >> >
> >> > introduce irq_inuse() macro and remove ifdef in stat.c
> >>
> >> should have a good name... irq_inuse is some confusing.
> >
> > Why?
> > May I ask your perfered name?
> 
> after freeing msi with dynamic_irq_cleanup(), that irq_desc is not used.

hm, instead, How about following patch?



=======
Subject: [PATCH] proc: remove ifdef CONFIG_SPARSE_IRQ from stat.c
Impact: cleanup

irq_desc can be NULL when CONFIG_SPARSE_IRQ=y only.
therefore, NULL checking can move into kstat_irqs_cpu() of SPARSE_IRQ version.


Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
---
 fs/proc/stat.c      |   11 +----------
 kernel/irq/handle.c |    2 +-
 2 files changed, 2 insertions(+), 11 deletions(-)

Index: b/fs/proc/stat.c
===================================================================
--- a/fs/proc/stat.c
+++ b/fs/proc/stat.c
@@ -9,6 +9,7 @@
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/time.h>
+#include <linux/irqnr.h>
 #include <asm/cputime.h>
 
 #ifndef arch_irq_stat_cpu
@@ -45,10 +46,6 @@ static int show_stat(struct seq_file *p,
 		steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal);
 		guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest);
 		for_each_irq_nr(j) {
-#ifdef CONFIG_SPARSE_IRQ
-			if (!irq_to_desc(j))
-				continue;
-#endif
 			sum += kstat_irqs_cpu(j, i);
 		}
 		sum += arch_irq_stat_cpu(i);
@@ -95,12 +92,6 @@ static int show_stat(struct seq_file *p,
 	/* sum again ? it could be updated? */
 	for_each_irq_nr(j) {
 		per_irq_sum = 0;
-#ifdef CONFIG_SPARSE_IRQ
-		if (!irq_to_desc(j)) {
-			seq_printf(p, " %u", per_irq_sum);
-			continue;
-		}
-#endif
 		for_each_possible_cpu(i)
 			per_irq_sum += kstat_irqs_cpu(j, i);
 
Index: b/kernel/irq/handle.c
===================================================================
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -445,7 +445,7 @@ void early_init_irq_lock_class(void)
 unsigned int kstat_irqs_cpu(unsigned int irq, int cpu)
 {
 	struct irq_desc *desc = irq_to_desc(irq);
-	return desc->kstat_irqs[cpu];
+	return desc ? desc->kstat_irqs[cpu] : 0;
 }
 #endif
 EXPORT_SYMBOL(kstat_irqs_cpu);