[PATCH 2/3] irqchip/irq-sifive-plic: Fixup couldn't broadcast to multi CPUs

From: guoren
Date: Fri Oct 23 2020 - 06:18:30 EST


From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>

If "echo 3 > /proc/irq/1/smp_affinity", we want irq 1 could be
broadcast to CPU0 & CPU1 and one of them would pick up the irq
handler.

But current implementation couldn't let multi CPUs process the
same IRQ concurrent.

Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
---
drivers/irqchip/irq-sifive-plic.c | 23 ++++++-----------------
1 file changed, 6 insertions(+), 17 deletions(-)

diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
index 2e56576..0003322 100644
--- a/drivers/irqchip/irq-sifive-plic.c
+++ b/drivers/irqchip/irq-sifive-plic.c
@@ -114,15 +114,12 @@ static inline void plic_irq_toggle(const struct cpumask *mask,
static void plic_irq_unmask(struct irq_data *d)
{
struct cpumask amask;
- unsigned int cpu;
struct plic_priv *priv = irq_get_chip_data(d->irq);

cpumask_and(&amask, &priv->lmask, cpu_online_mask);
- cpu = cpumask_any_and(irq_data_get_affinity_mask(d),
- &amask);
- if (WARN_ON_ONCE(cpu >= nr_cpu_ids))
- return;
- plic_irq_toggle(cpumask_of(cpu), d, 1);
+ cpumask_and(&amask, &amask, irq_data_get_affinity_mask(d));
+
+ plic_irq_toggle(&amask, d, 1);
}

static void plic_irq_mask(struct irq_data *d)
@@ -136,24 +133,16 @@ static void plic_irq_mask(struct irq_data *d)
static int plic_set_affinity(struct irq_data *d,
const struct cpumask *mask_val, bool force)
{
- unsigned int cpu;
struct cpumask amask;
struct plic_priv *priv = irq_get_chip_data(d->irq);

cpumask_and(&amask, &priv->lmask, mask_val);
+ cpumask_and(&amask, &amask, cpu_online_mask);

- if (force)
- cpu = cpumask_first(&amask);
- else
- cpu = cpumask_any_and(&amask, cpu_online_mask);
-
- if (cpu >= nr_cpu_ids)
- return -EINVAL;
+ irq_data_update_effective_affinity(d, &amask);

plic_irq_toggle(&priv->lmask, d, 0);
- plic_irq_toggle(cpumask_of(cpu), d, 1);
-
- irq_data_update_effective_affinity(d, cpumask_of(cpu));
+ plic_irq_toggle(&amask, d, 1);

return IRQ_SET_MASK_OK_DONE;
}
--
2.7.4