irq: clear kstat_irqs
Impact: get correct kstat_irqs [/proc/interrupts] for msi/msi-x etc
need to call clear_kstat_irqs(), so when we reuse that irq_desc,
we get correct kstat in /proc/interrupts.
This makes /proc/interrupts not have <NULL> entries.
Don't need to worry about arch that doesn't support genirq, because they
will not call dynamic_irq_cleanup().
v2: simplify and make clear_kstat_irqs more robust
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index f63c706..1310856 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -78,6 +78,7 @@
desc->handle_irq = handle_bad_irq;
desc->chip = &no_irq_chip;
desc->name = NULL;
+ clear_kstat_irqs(desc);
spin_unlock_irqrestore(&desc->lock, flags);
}
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 48299a8..1b473e7 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -242,6 +242,11 @@
}
#endif /* !CONFIG_SPARSE_IRQ */
+void clear_kstat_irqs(struct irq_desc *desc)
+{
+ memset(desc->kstat_irqs, 0, nr_cpu_ids * sizeof(*(desc->kstat_irqs)));
+}
+
/*
* What should we do if we get a hw irq event on an illegal vector?
* Each architecture has to answer this themself.
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index e6d0a43..b60950b 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -15,6 +15,7 @@
extern struct lock_class_key irq_desc_lock_class;
extern void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr);
+extern void clear_kstat_irqs(struct irq_desc *desc);
extern spinlock_t sparse_irq_lock;
extern struct irq_desc *irq_desc_ptrs[NR_IRQS];