[PATCH 01/12] genirq: Restrict effective affinity to single-target interrupts

From: Marc Zyngier
Date: Tue Aug 15 2017 - 07:38:19 EST


Just because CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK is selected
doesn't mean that all the interrupts are using the effective
affinity mask. For a number of them, this mask is likely to
be empty.

In order to deal with this, let's restrict the use of the
effective affinity mask to these interrupts that have been
configured as "single target".

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
include/linux/irq.h | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index d2d543794093..af1510642b8a 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -781,7 +781,10 @@ static inline struct cpumask *irq_data_get_affinity_mask(struct irq_data *d)
static inline
struct cpumask *irq_data_get_effective_affinity_mask(struct irq_data *d)
{
- return d->common->effective_affinity;
+ if (irqd_is_single_target(d))
+ return d->common->effective_affinity;
+ else
+ return d->common->affinity;
}
static inline void irq_data_update_effective_affinity(struct irq_data *d,
const struct cpumask *m)
--
2.11.0