Most users of kstat_irqs_cpu() have the irq descriptor already. No point in calling into the core code and looking it up once more. Use it in per_cpu_count_show() to start with. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> --- include/linux/irqdesc.h | 6 ++++++ kernel/irq/irqdesc.c | 4 ++-- 2 files changed, 8 insertions(+), 2 deletions(-) --- a/include/linux/irqdesc.h +++ b/include/linux/irqdesc.h @@ -113,6 +113,12 @@ static inline void irq_unlock_sparse(voi extern struct irq_desc irq_desc[NR_IRQS]; #endif +static inline unsigned int irq_desc_kstat_cpu(struct irq_desc *desc, + unsigned int cpu) +{ + return desc->kstat_irqs ? *per_cpu_ptr(desc->kstat_irqs, cpu) : 0; +} + static inline struct irq_desc *irq_data_to_desc(struct irq_data *data) { return container_of(data->common, struct irq_desc, irq_common_data); --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -147,12 +147,12 @@ static ssize_t per_cpu_count_show(struct struct kobj_attribute *attr, char *buf) { struct irq_desc *desc = container_of(kobj, struct irq_desc, kobj); - int cpu, irq = desc->irq_data.irq; ssize_t ret = 0; char *p = ""; + int cpu; for_each_possible_cpu(cpu) { - unsigned int c = kstat_irqs_cpu(irq, cpu); + unsigned int c = irq_desc_kstat_cpu(desc, cpu); ret += scnprintf(buf + ret, PAGE_SIZE - ret, "%s%u", p, c); p = ",";