[PATCH] irqchip/gicv3-its: skip irq affinity setting when target cpu is the same as current setting

[Majun]

From: MaJun <majun...@huawei.com>

Just skip the irq affinity setting when the target cpu is the same as
current setting.
This is a small optimization for irq affinity setting logic.

Signed-off-by: MaJun <majun...@huawei.com>
---
 drivers/irqchip/irq-gic-v3-its.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 45ea1933..b335280 100644
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -644,9 +644,12 @@ static int its_set_affinity(struct irq_data *d, const 
struct cpumask *mask_val,
        if (cpu >= nr_cpu_ids)
                return -EINVAL;
 
-       target_col = &its_dev->its->collections[cpu];
-       its_send_movi(its_dev, target_col, id);
-       its_dev->event_map.col_map[id] = cpu;
+       /* don't set the affinity when the target cpu is same as current one */
+       if (cpu != its_dev->event_map.col_map[id]) {
+               target_col = &its_dev->its->collections[cpu];
+               its_send_movi(its_dev, target_col, id);
+               its_dev->event_map.col_map[id] = cpu;
+       }
 
        return IRQ_SET_MASK_OK_DONE;
 }
-- 
1.7.12.4