[patch 08/30] genirq: Provide kstat_irqdesc_cpu()

From: Thomas Gleixner
Date: Thu Dec 10 2020 - 15:01:30 EST


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 = ",";